Merge branch 'wwan-t7xx-fw-flashing-and-coredump-support'

M Chetan Kumar says:

====================
net: wwan: t7xx: fw flashing & coredump support

This patch series brings-in the support for FM350 wwan device firmware
flashing & coredump collection using devlink interface.

Below is the high level description of individual patches.
Refer to individual patch commit message for details.

PATCH1:  Enables AP CLDMA communication for firmware flashing &
coredump collection.

PATCH2: Enables the infrastructure & queue configuration required
for early ports enumeration.

PATCH3: Implements device reset and rescan logic required to enter
or exit fastboot mode.

PATCH4: Implements devlink interface & uses the fastboot protocol for
fw flashing and coredump collection.

PATCH5: t7xx devlink commands documentation.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/networking/devlink/index.rst

@@ -67,3 +67,4 @@ parameters, info versions, and other features it supports.
    prestera
    iosm
    octeontx2
+   t7xx

Documentation/networking/devlink/t7xx.rst

+.. SPDX-License-Identifier: GPL-2.0
+
+====================
+t7xx devlink support
+====================
+
+This document describes the devlink features implemented by the ``t7xx``
+device driver.
+
+Flash Update
+============
+
+The ``t7xx`` driver implements the flash update using the ``devlink-flash``
+interface.
+
+The driver uses DEVLINK_SUPPORT_FLASH_UPDATE_COMPONENT to identify the type of
+firmware image that need to be programmed upon the request by user space application.
+
+The supported list of firmware image types is described below.
+
+.. list-table:: Firmware Image types
+    :widths: 15 85
+
+    * - Name
+      - Description
+    * - ``preloader``
+      - The first-stage bootloader image
+    * - ``loader_ext1``
+      - Preloader extension image
+    * - ``tee1``
+      - ARM trusted firmware and TEE (Trusted Execution Environment) image
+    * - ``lk``
+      - The second-stage bootloader image
+    * - ``spmfw``
+      - MediaTek in-house ASIC for power management image
+    * - ``sspm_1``
+      - MediaTek in-house ASIC for power management under secure world image
+    * - ``mcupm_1``
+      - MediaTek in-house ASIC for cpu power management image
+    * - ``dpm_1``
+      - MediaTek in-house ASIC for dram power management image
+    * - ``boot``
+      - The kernel and dtb image
+    * - ``rootfs``
+      - Root filesystem image
+    * - ``md1img``
+      - Modem image
+    * - ``md1dsp``
+      - Modem DSP image
+    * - ``mcf1``
+      - Modem OTA image (Modem Configuration Framework) for operators
+    * - ``mcf2``
+      - Modem OTA image (Modem Configuration Framework) for OEM vendors
+    * - ``mcf3``
+      - Modem OTA image (other usage) for OEM configurations
+
+``t7xx`` driver uses fastboot protocol for fw flashing. In the fw flashing
+procedure, fastboot command's & response's are exchanged between driver
+and wwan device.
+
+The wwan device is put into fastboot mode via devlink reload command, by
+passing "driver_reinit" action.
+
+$ devlink dev reload pci/0000:$bdf action driver_reinit
+
+Upon completion of fw flashing or coredump collection the wwan device is
+reset to normal mode using devlink reload command, by passing "fw_activate"
+action.
+
+$ devlink dev reload pci/0000:$bdf action fw_activate
+
+Flash Commands:
+===============
+
+$ devlink dev flash pci/0000:$bdf file preloader_k6880v1_mdot2_datacard.bin component "preloader"
+
+$ devlink dev flash pci/0000:$bdf file loader_ext-verified.img component "loader_ext1"
+
+$ devlink dev flash pci/0000:$bdf file tee-verified.img component "tee1"
+
+$ devlink dev flash pci/0000:$bdf file lk-verified.img component "lk"
+
+$ devlink dev flash pci/0000:$bdf file spmfw-verified.img component "spmfw"
+
+$ devlink dev flash pci/0000:$bdf file sspm-verified.img component "sspm_1"
+
+$ devlink dev flash pci/0000:$bdf file mcupm-verified.img component "mcupm_1"
+
+$ devlink dev flash pci/0000:$bdf file dpm-verified.img component "dpm_1"
+
+$ devlink dev flash pci/0000:$bdf file boot-verified.img component "boot"
+
+$ devlink dev flash pci/0000:$bdf file root.squashfs component "rootfs"
+
+$ devlink dev flash pci/0000:$bdf file modem-verified.img component "md1img"
+
+$ devlink dev flash pci/0000:$bdf file dsp-verified.bin component "md1dsp"
+
+$ devlink dev flash pci/0000:$bdf file OP_OTA.img component "mcf1"
+
+$ devlink dev flash pci/0000:$bdf file OEM_OTA.img component "mcf2"
+
+$ devlink dev flash pci/0000:$bdf file DEV_OTA.img component "mcf3"
+
+Note: component "value" represents the partition type to be programmed.
+
+Regions
+=======
+
+The ``t7xx`` driver supports core dump collection when device encounters
+an exception. When wwan device encounters an exception, a snapshot of device
+internal data will be taken by the driver using fastboot commands.
+
+Following regions are accessed for device internal data.
+
+.. list-table:: Regions implemented
+    :widths: 15 85
+
+    * - Name
+      - Description
+    * - ``mr_dump``
+      - The detailed modem components log are captured in this region
+    * - ``lk_dump``
+      - This region dumps the current snapshot of lk
+
+
+Region commands
+===============
+
+$ devlink region show
+
+
+$ devlink region new mr_dump
+
+$ devlink region read mr_dump snapshot 0 address 0 length $len
+
+$ devlink region del mr_dump snapshot 0
+
+$ devlink region new lk_dump
+
+$ devlink region read lk_dump snapshot 0 address 0 length $len
+
+$ devlink region del lk_dump snapshot 0
+
+Note: $len is actual len to be dumped.

drivers/net/wwan/Kconfig

@@ -108,6 +108,7 @@ config IOSM
 config MTK_T7XX
 	tristate "MediaTek PCIe 5G WWAN modem T7xx device"
 	depends on PCI
+	select NET_DEVLINK
 	help
 	  Enables MediaTek PCIe based 5G WWAN modem (T7xx series) device.
 	  Adapts WWAN framework and provides network interface like wwan0

drivers/net/wwan/t7xx/Makefile

@@ -17,4 +17,7 @@ mtk_t7xx-y:=	t7xx_pci.o \
 		t7xx_hif_dpmaif_tx.o \
 		t7xx_hif_dpmaif_rx.o  \
 		t7xx_dpmaif.o \
-		t7xx_netdev.o
+		t7xx_netdev.o \
+		t7xx_pci_rescan.o \
+		t7xx_uevent.o \
+		t7xx_port_devlink.o

drivers/net/wwan/t7xx/t7xx_hif_cldma.c

@@ -57,8 +57,6 @@
 #define CHECK_Q_STOP_TIMEOUT_US		1000000
 #define CHECK_Q_STOP_STEP_US		10000
 
-#define CLDMA_JUMBO_BUFF_SZ		(63 * 1024 + sizeof(struct ccci_header))
-
 static void md_cd_queue_struct_reset(struct cldma_queue *queue, struct cldma_ctrl *md_ctrl,
 				     enum mtk_txrx tx_rx, unsigned int index)
 {
@@ -993,6 +991,34 @@ int t7xx_cldma_send_skb(struct cldma_ctrl *md_ctrl, int qno, struct sk_buff *skb
 	return ret;
 }
 
+static void t7xx_cldma_adjust_config(struct cldma_ctrl *md_ctrl, enum cldma_cfg cfg_id)
+{
+	int qno;
+
+	for (qno = 0; qno < CLDMA_RXQ_NUM; qno++) {
+		md_ctrl->rx_ring[qno].pkt_size = CLDMA_SHARED_Q_BUFF_SZ;
+		md_ctrl->rxq[qno].q_type = CLDMA_SHARED_Q;
+	}
+
+	md_ctrl->rx_ring[CLDMA_RXQ_NUM - 1].pkt_size = CLDMA_JUMBO_BUFF_SZ;
+
+	for (qno = 0; qno < CLDMA_TXQ_NUM; qno++) {
+		md_ctrl->tx_ring[qno].pkt_size = CLDMA_SHARED_Q_BUFF_SZ;
+		md_ctrl->txq[qno].q_type = CLDMA_SHARED_Q;
+	}
+
+	if (cfg_id == CLDMA_DEDICATED_Q_CFG) {
+		md_ctrl->rxq[DOWNLOAD_PORT_ID].q_type = CLDMA_DEDICATED_Q;
+		md_ctrl->txq[DOWNLOAD_PORT_ID].q_type = CLDMA_DEDICATED_Q;
+		md_ctrl->tx_ring[DOWNLOAD_PORT_ID].pkt_size = CLDMA_DEDICATED_Q_BUFF_SZ;
+		md_ctrl->rx_ring[DOWNLOAD_PORT_ID].pkt_size = CLDMA_DEDICATED_Q_BUFF_SZ;
+		md_ctrl->rxq[DUMP_PORT_ID].q_type = CLDMA_DEDICATED_Q;
+		md_ctrl->txq[DUMP_PORT_ID].q_type = CLDMA_DEDICATED_Q;
+		md_ctrl->tx_ring[DUMP_PORT_ID].pkt_size = CLDMA_DEDICATED_Q_BUFF_SZ;
+		md_ctrl->rx_ring[DUMP_PORT_ID].pkt_size = CLDMA_DEDICATED_Q_BUFF_SZ;
+	}
+}
+
 static int t7xx_cldma_late_init(struct cldma_ctrl *md_ctrl)
 {
 	char dma_pool_name[32];
@@ -1021,11 +1047,6 @@ static int t7xx_cldma_late_init(struct cldma_ctrl *md_ctrl)
 	}
 
 	for (j = 0; j < CLDMA_RXQ_NUM; j++) {
-		md_ctrl->rx_ring[j].pkt_size = CLDMA_MTU;
-
-		if (j == CLDMA_RXQ_NUM - 1)
-			md_ctrl->rx_ring[j].pkt_size = CLDMA_JUMBO_BUFF_SZ;
-
 		ret = t7xx_cldma_rx_ring_init(md_ctrl, &md_ctrl->rx_ring[j]);
 		if (ret) {
 			dev_err(md_ctrl->dev, "Control RX ring init fail\n");
@@ -1064,13 +1085,18 @@ static void t7xx_hw_info_init(struct cldma_ctrl *md_ctrl)
 	struct t7xx_cldma_hw *hw_info = &md_ctrl->hw_info;
 	u32 phy_ao_base, phy_pd_base;
 
-	if (md_ctrl->hif_id != CLDMA_ID_MD)
-		return;
-
-	phy_ao_base = CLDMA1_AO_BASE;
-	phy_pd_base = CLDMA1_PD_BASE;
-	hw_info->phy_interrupt_id = CLDMA1_INT;
 	hw_info->hw_mode = MODE_BIT_64;
+
+	if (md_ctrl->hif_id == CLDMA_ID_MD) {
+		phy_ao_base = CLDMA1_AO_BASE;
+		phy_pd_base = CLDMA1_PD_BASE;
+		hw_info->phy_interrupt_id = CLDMA1_INT;
+	} else {
+		phy_ao_base = CLDMA0_AO_BASE;
+		phy_pd_base = CLDMA0_PD_BASE;
+		hw_info->phy_interrupt_id = CLDMA0_INT;
+	}
+
 	hw_info->ap_ao_base = t7xx_pcie_addr_transfer(pbase->pcie_ext_reg_base,
 						      pbase->pcie_dev_reg_trsl_addr, phy_ao_base);
 	hw_info->ap_pdn_base = t7xx_pcie_addr_transfer(pbase->pcie_ext_reg_base,
@@ -1324,9 +1350,10 @@ int t7xx_cldma_init(struct cldma_ctrl *md_ctrl)
 	return -ENOMEM;
 }
 
-void t7xx_cldma_switch_cfg(struct cldma_ctrl *md_ctrl)
+void t7xx_cldma_switch_cfg(struct cldma_ctrl *md_ctrl, enum cldma_cfg cfg_id)
 {
 	t7xx_cldma_late_release(md_ctrl);
+	t7xx_cldma_adjust_config(md_ctrl, cfg_id);
 	t7xx_cldma_late_init(md_ctrl);
 }
 

drivers/net/wwan/t7xx/t7xx_hif_cldma.h

@@ -31,10 +31,14 @@
 #include "t7xx_cldma.h"
 #include "t7xx_pci.h"
 
+#define CLDMA_JUMBO_BUFF_SZ		(63 * 1024 + sizeof(struct ccci_header))
+#define CLDMA_SHARED_Q_BUFF_SZ		3584
+#define CLDMA_DEDICATED_Q_BUFF_SZ	2048
+
 /**
  * enum cldma_id - Identifiers for CLDMA HW units.
  * @CLDMA_ID_MD: Modem control channel.
- * @CLDMA_ID_AP: Application Processor control channel (not used at the moment).
+ * @CLDMA_ID_AP: Application Processor control channel.
  * @CLDMA_NUM:   Number of CLDMA HW units available.
  */
 enum cldma_id {
@@ -55,6 +59,16 @@ struct cldma_gpd {
 	__le16 not_used2;
 };
 
+enum cldma_queue_type {
+	CLDMA_SHARED_Q,
+	CLDMA_DEDICATED_Q,
+};
+
+enum cldma_cfg {
+	CLDMA_SHARED_Q_CFG,
+	CLDMA_DEDICATED_Q_CFG,
+};
+
 struct cldma_request {
 	struct cldma_gpd *gpd;	/* Virtual address for CPU */
 	dma_addr_t gpd_addr;	/* Physical address for DMA */
@@ -77,6 +91,7 @@ struct cldma_queue {
 	struct cldma_request *tr_done;
 	struct cldma_request *rx_refill;
 	struct cldma_request *tx_next;
+	enum cldma_queue_type q_type;
 	int budget;			/* Same as ring buffer size by default */
 	spinlock_t ring_lock;
 	wait_queue_head_t req_wq;	/* Only for TX */
@@ -104,17 +119,20 @@ struct cldma_ctrl {
 	int (*recv_skb)(struct cldma_queue *queue, struct sk_buff *skb);
 };
 
+enum cldma_txq_rxq_port_id {
+	DOWNLOAD_PORT_ID = 0,
+	DUMP_PORT_ID = 1
+};
+
 #define GPD_FLAGS_HWO		BIT(0)
 #define GPD_FLAGS_IOC		BIT(7)
 #define GPD_DMAPOOL_ALIGN	16
 
-#define CLDMA_MTU		3584	/* 3.5kB */
-
 int t7xx_cldma_alloc(enum cldma_id hif_id, struct t7xx_pci_dev *t7xx_dev);
 void t7xx_cldma_hif_hw_init(struct cldma_ctrl *md_ctrl);
 int t7xx_cldma_init(struct cldma_ctrl *md_ctrl);
 void t7xx_cldma_exit(struct cldma_ctrl *md_ctrl);
-void t7xx_cldma_switch_cfg(struct cldma_ctrl *md_ctrl);
+void t7xx_cldma_switch_cfg(struct cldma_ctrl *md_ctrl, enum cldma_cfg cfg_id);
 void t7xx_cldma_start(struct cldma_ctrl *md_ctrl);
 int t7xx_cldma_stop(struct cldma_ctrl *md_ctrl);
 void t7xx_cldma_reset(struct cldma_ctrl *md_ctrl);

drivers/net/wwan/t7xx/t7xx_mhccif.h

@@ -25,6 +25,7 @@
 			 D2H_INT_EXCEPTION_CLEARQ_DONE |	\
 			 D2H_INT_EXCEPTION_ALLQ_RESET |		\
 			 D2H_INT_PORT_ENUM |			\
+			 D2H_INT_ASYNC_AP_HK |			\
 			 D2H_INT_ASYNC_MD_HK)
 
 void t7xx_mhccif_mask_set(struct t7xx_pci_dev *t7xx_dev, u32 val);

drivers/net/wwan/t7xx/t7xx_modem_ops.c

@@ -37,6 +37,7 @@
 #include "t7xx_modem_ops.h"
 #include "t7xx_netdev.h"
 #include "t7xx_pci.h"
+#include "t7xx_pci_rescan.h"
 #include "t7xx_pcie_mac.h"
 #include "t7xx_port.h"
 #include "t7xx_port_proxy.h"
@@ -44,6 +45,7 @@
 #include "t7xx_state_monitor.h"
 
 #define RT_ID_MD_PORT_ENUM	0
+#define RT_ID_AP_PORT_ENUM	1
 /* Modem feature query identification code - "ICCC" */
 #define MD_FEATURE_QUERY_ID	0x49434343
 
@@ -191,6 +193,10 @@ static irqreturn_t t7xx_rgu_isr_thread(int irq, void *data)
 
 	msleep(RGU_RESET_DELAY_MS);
 	t7xx_reset_device_via_pmic(t7xx_dev);
+
+	if (!t7xx_dev->hp_enable)
+		t7xx_rescan_queue_work(t7xx_dev->pdev);
+
 	return IRQ_HANDLED;
 }
 
@@ -296,6 +302,7 @@ static void t7xx_md_exception(struct t7xx_modem *md, enum hif_ex_stage stage)
 	}
 
 	t7xx_cldma_exception(md->md_ctrl[CLDMA_ID_MD], stage);
+	t7xx_cldma_exception(md->md_ctrl[CLDMA_ID_AP], stage);
 
 	if (stage == HIF_EX_INIT)
 		t7xx_mhccif_h2d_swint_trigger(t7xx_dev, H2D_CH_EXCEPTION_ACK);
@@ -424,7 +431,7 @@ static int t7xx_parse_host_rt_data(struct t7xx_fsm_ctl *ctl, struct t7xx_sys_inf
 		if (ft_spt_st != MTK_FEATURE_MUST_BE_SUPPORTED)
 			return -EINVAL;
 
-		if (i == RT_ID_MD_PORT_ENUM)
+		if (i == RT_ID_MD_PORT_ENUM || i == RT_ID_AP_PORT_ENUM)
 			t7xx_port_enum_msg_handler(ctl->md, rt_feature->data);
 	}
 
@@ -454,12 +461,12 @@ static int t7xx_core_reset(struct t7xx_modem *md)
 	return 0;
 }
 
-static void t7xx_core_hk_handler(struct t7xx_modem *md, struct t7xx_fsm_ctl *ctl,
+static void t7xx_core_hk_handler(struct t7xx_modem *md, struct t7xx_sys_info *core_info,
+				 struct t7xx_fsm_ctl *ctl,
 				 enum t7xx_fsm_event_state event_id,
 				 enum t7xx_fsm_event_state err_detect)
 {
 	struct t7xx_fsm_event *event = NULL, *event_next;
-	struct t7xx_sys_info *core_info = &md->core_md;
 	struct device *dev = &md->t7xx_dev->pdev->dev;
 	unsigned long flags;
 	int ret;
@@ -525,23 +532,37 @@ static void t7xx_md_hk_wq(struct work_struct *work)
 
 	/* Clear the HS2 EXIT event appended in core_reset() */
 	t7xx_fsm_clr_event(ctl, FSM_EVENT_MD_HS2_EXIT);
-	t7xx_cldma_switch_cfg(md->md_ctrl[CLDMA_ID_MD]);
+	t7xx_cldma_switch_cfg(md->md_ctrl[CLDMA_ID_MD], CLDMA_SHARED_Q_CFG);
 	t7xx_cldma_start(md->md_ctrl[CLDMA_ID_MD]);
 	t7xx_fsm_broadcast_state(ctl, MD_STATE_WAITING_FOR_HS2);
 	md->core_md.handshake_ongoing = true;
-	t7xx_core_hk_handler(md, ctl, FSM_EVENT_MD_HS2, FSM_EVENT_MD_HS2_EXIT);
+	t7xx_core_hk_handler(md, &md->core_md, ctl, FSM_EVENT_MD_HS2, FSM_EVENT_MD_HS2_EXIT);
+}
+
+static void t7xx_ap_hk_wq(struct work_struct *work)
+{
+	struct t7xx_modem *md = container_of(work, struct t7xx_modem, ap_handshake_work);
+	struct t7xx_fsm_ctl *ctl = md->fsm_ctl;
+
+	 /* Clear the HS2 EXIT event appended in t7xx_core_reset(). */
+	t7xx_fsm_clr_event(ctl, FSM_EVENT_AP_HS2_EXIT);
+	t7xx_cldma_stop(md->md_ctrl[CLDMA_ID_AP]);
+	t7xx_cldma_switch_cfg(md->md_ctrl[CLDMA_ID_AP], CLDMA_SHARED_Q_CFG);
+	t7xx_cldma_start(md->md_ctrl[CLDMA_ID_AP]);
+	md->core_ap.handshake_ongoing = true;
+	t7xx_core_hk_handler(md, &md->core_ap, ctl, FSM_EVENT_AP_HS2, FSM_EVENT_AP_HS2_EXIT);
 }
 
 void t7xx_md_event_notify(struct t7xx_modem *md, enum md_event_id evt_id)
 {
 	struct t7xx_fsm_ctl *ctl = md->fsm_ctl;
-	void __iomem *mhccif_base;
 	unsigned int int_sta;
 	unsigned long flags;
 
 	switch (evt_id) {
 	case FSM_PRE_START:
-		t7xx_mhccif_mask_clr(md->t7xx_dev, D2H_INT_PORT_ENUM);
+		t7xx_mhccif_mask_clr(md->t7xx_dev, D2H_INT_PORT_ENUM | D2H_INT_ASYNC_MD_HK |
+						   D2H_INT_ASYNC_AP_HK);
 		break;
 
 	case FSM_START:
@@ -554,16 +575,26 @@ void t7xx_md_event_notify(struct t7xx_modem *md, enum md_event_id evt_id)
 			ctl->exp_flg = true;
 			md->exp_id &= ~D2H_INT_EXCEPTION_INIT;
 			md->exp_id &= ~D2H_INT_ASYNC_MD_HK;
+			md->exp_id &= ~D2H_INT_ASYNC_AP_HK;
 		} else if (ctl->exp_flg) {
 			md->exp_id &= ~D2H_INT_ASYNC_MD_HK;
-		} else if (md->exp_id & D2H_INT_ASYNC_MD_HK) {
-			queue_work(md->handshake_wq, &md->handshake_work);
-			md->exp_id &= ~D2H_INT_ASYNC_MD_HK;
-			mhccif_base = md->t7xx_dev->base_addr.mhccif_rc_base;
-			iowrite32(D2H_INT_ASYNC_MD_HK, mhccif_base + REG_EP2RC_SW_INT_ACK);
-			t7xx_mhccif_mask_set(md->t7xx_dev, D2H_INT_ASYNC_MD_HK);
+			md->exp_id &= ~D2H_INT_ASYNC_AP_HK;
 		} else {
-			t7xx_mhccif_mask_clr(md->t7xx_dev, D2H_INT_ASYNC_MD_HK);
+			void __iomem *mhccif_base = md->t7xx_dev->base_addr.mhccif_rc_base;
+
+			if (md->exp_id & D2H_INT_ASYNC_MD_HK) {
+				queue_work(md->handshake_wq, &md->handshake_work);
+				md->exp_id &= ~D2H_INT_ASYNC_MD_HK;
+				iowrite32(D2H_INT_ASYNC_MD_HK, mhccif_base + REG_EP2RC_SW_INT_ACK);
+				t7xx_mhccif_mask_set(md->t7xx_dev, D2H_INT_ASYNC_MD_HK);
+			}
+
+			if (md->exp_id & D2H_INT_ASYNC_AP_HK) {
+				queue_work(md->ap_handshake_wq, &md->ap_handshake_work);
+				md->exp_id &= ~D2H_INT_ASYNC_AP_HK;
+				iowrite32(D2H_INT_ASYNC_AP_HK, mhccif_base + REG_EP2RC_SW_INT_ACK);
+				t7xx_mhccif_mask_set(md->t7xx_dev, D2H_INT_ASYNC_AP_HK);
+			}
 		}
 		spin_unlock_irqrestore(&md->exp_lock, flags);
 
@@ -576,6 +607,7 @@ void t7xx_md_event_notify(struct t7xx_modem *md, enum md_event_id evt_id)
 
 	case FSM_READY:
 		t7xx_mhccif_mask_set(md->t7xx_dev, D2H_INT_ASYNC_MD_HK);
+		t7xx_mhccif_mask_set(md->t7xx_dev, D2H_INT_ASYNC_AP_HK);
 		break;
 
 	default:
@@ -627,6 +659,19 @@ static struct t7xx_modem *t7xx_md_alloc(struct t7xx_pci_dev *t7xx_dev)
 	md->core_md.feature_set[RT_ID_MD_PORT_ENUM] &= ~FEATURE_MSK;
 	md->core_md.feature_set[RT_ID_MD_PORT_ENUM] |=
 		FIELD_PREP(FEATURE_MSK, MTK_FEATURE_MUST_BE_SUPPORTED);
+
+	md->ap_handshake_wq = alloc_workqueue("%s", WQ_UNBOUND | WQ_MEM_RECLAIM | WQ_HIGHPRI,
+					      0, "ap_hk_wq");
+	if (!md->ap_handshake_wq) {
+		destroy_workqueue(md->handshake_wq);
+		return NULL;
+	}
+
+	INIT_WORK(&md->ap_handshake_work, t7xx_ap_hk_wq);
+	md->core_ap.feature_set[RT_ID_AP_PORT_ENUM] &= ~FEATURE_MSK;
+	md->core_ap.feature_set[RT_ID_AP_PORT_ENUM] |=
+		FIELD_PREP(FEATURE_MSK, MTK_FEATURE_MUST_BE_SUPPORTED);
+
 	return md;
 }
 
@@ -638,6 +683,7 @@ int t7xx_md_reset(struct t7xx_pci_dev *t7xx_dev)
 	md->exp_id = 0;
 	t7xx_fsm_reset(md);
 	t7xx_cldma_reset(md->md_ctrl[CLDMA_ID_MD]);
+	t7xx_cldma_reset(md->md_ctrl[CLDMA_ID_AP]);
 	t7xx_port_proxy_reset(md->port_prox);
 	md->md_init_finish = true;
 	return t7xx_core_reset(md);
@@ -667,6 +713,10 @@ int t7xx_md_init(struct t7xx_pci_dev *t7xx_dev)
 	if (ret)
 		goto err_destroy_hswq;
 
+	ret = t7xx_cldma_alloc(CLDMA_ID_AP, t7xx_dev);
+	if (ret)
+		goto err_destroy_hswq;
+
 	ret = t7xx_fsm_init(md);
 	if (ret)
 		goto err_destroy_hswq;
@@ -679,12 +729,16 @@ int t7xx_md_init(struct t7xx_pci_dev *t7xx_dev)
 	if (ret)
 		goto err_uninit_ccmni;
 
-	ret = t7xx_port_proxy_init(md);
+	ret = t7xx_cldma_init(md->md_ctrl[CLDMA_ID_AP]);
 	if (ret)
 		goto err_uninit_md_cldma;
 
+	ret = t7xx_port_proxy_init(md);
+	if (ret)
+		goto err_uninit_ap_cldma;
+
 	ret = t7xx_fsm_append_cmd(md->fsm_ctl, FSM_CMD_START, 0);
-	if (ret) /* fsm_uninit flushes cmd queue */
+	if (ret) /* t7xx_fsm_uninit() flushes cmd queue */
 		goto err_uninit_proxy;
 
 	t7xx_md_sys_sw_init(t7xx_dev);
@@ -694,6 +748,9 @@ int t7xx_md_init(struct t7xx_pci_dev *t7xx_dev)
 err_uninit_proxy:
 	t7xx_port_proxy_uninit(md->port_prox);
 
+err_uninit_ap_cldma:
+	t7xx_cldma_exit(md->md_ctrl[CLDMA_ID_AP]);
+
 err_uninit_md_cldma:
 	t7xx_cldma_exit(md->md_ctrl[CLDMA_ID_MD]);
 
@@ -705,6 +762,7 @@ int t7xx_md_init(struct t7xx_pci_dev *t7xx_dev)
 
 err_destroy_hswq:
 	destroy_workqueue(md->handshake_wq);
+	destroy_workqueue(md->ap_handshake_wq);
 	dev_err(&t7xx_dev->pdev->dev, "Modem init failed\n");
 	return ret;
 }
@@ -720,8 +778,10 @@ void t7xx_md_exit(struct t7xx_pci_dev *t7xx_dev)
 
 	t7xx_fsm_append_cmd(md->fsm_ctl, FSM_CMD_PRE_STOP, FSM_CMD_FLAG_WAIT_FOR_COMPLETION);
 	t7xx_port_proxy_uninit(md->port_prox);
+	t7xx_cldma_exit(md->md_ctrl[CLDMA_ID_AP]);
 	t7xx_cldma_exit(md->md_ctrl[CLDMA_ID_MD]);
 	t7xx_ccmni_exit(t7xx_dev);
 	t7xx_fsm_uninit(md);
 	destroy_workqueue(md->handshake_wq);
+	destroy_workqueue(md->ap_handshake_wq);
 }

drivers/net/wwan/t7xx/t7xx_modem_ops.h

@@ -66,10 +66,13 @@ struct t7xx_modem {
 	struct cldma_ctrl		*md_ctrl[CLDMA_NUM];
 	struct t7xx_pci_dev		*t7xx_dev;
 	struct t7xx_sys_info		core_md;
+	struct t7xx_sys_info		core_ap;
 	bool				md_init_finish;
 	bool				rgu_irq_asserted;
 	struct workqueue_struct		*handshake_wq;
 	struct work_struct		handshake_work;
+	struct workqueue_struct		*ap_handshake_wq;
+	struct work_struct		ap_handshake_work;
 	struct t7xx_fsm_ctl		*fsm_ctl;
 	struct port_proxy		*port_prox;
 	unsigned int			exp_id;

drivers/net/wwan/t7xx/t7xx_pci.c

@@ -38,7 +38,9 @@
 #include "t7xx_mhccif.h"
 #include "t7xx_modem_ops.h"
 #include "t7xx_pci.h"
+#include "t7xx_pci_rescan.h"
 #include "t7xx_pcie_mac.h"
+#include "t7xx_port_devlink.h"
 #include "t7xx_reg.h"
 #include "t7xx_state_monitor.h"
 
@@ -703,22 +705,33 @@ static int t7xx_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	t7xx_pci_infracfg_ao_calc(t7xx_dev);
 	t7xx_mhccif_init(t7xx_dev);
 
-	ret = t7xx_md_init(t7xx_dev);
+	ret = t7xx_devlink_register(t7xx_dev);
 	if (ret)
 		return ret;
 
+	ret = t7xx_md_init(t7xx_dev);
+	if (ret)
+		goto err_devlink_unregister;
+
 	t7xx_pcie_mac_interrupts_dis(t7xx_dev);
 
 	ret = t7xx_interrupt_init(t7xx_dev);
 	if (ret) {
 		t7xx_md_exit(t7xx_dev);
-		return ret;
+		goto err_devlink_unregister;
 	}
 
+	t7xx_rescan_done();
 	t7xx_pcie_mac_set_int(t7xx_dev, MHCCIF_INT);
 	t7xx_pcie_mac_interrupts_en(t7xx_dev);
+	if (!t7xx_dev->hp_enable)
+		pci_ignore_hotplug(pdev);
 
 	return 0;
+
+err_devlink_unregister:
+	t7xx_devlink_unregister(t7xx_dev);
+	return ret;
 }
 
 static void t7xx_pci_remove(struct pci_dev *pdev)
@@ -728,6 +741,7 @@ static void t7xx_pci_remove(struct pci_dev *pdev)
 
 	t7xx_dev = pci_get_drvdata(pdev);
 	t7xx_md_exit(t7xx_dev);
+	t7xx_devlink_unregister(t7xx_dev);
 
 	for (i = 0; i < EXT_INT_NUM; i++) {
 		if (!t7xx_dev->intr_handler[i])
@@ -754,7 +768,52 @@ static struct pci_driver t7xx_pci_driver = {
 	.shutdown = t7xx_pci_shutdown,
 };
 
-module_pci_driver(t7xx_pci_driver);
+static int __init t7xx_pci_init(void)
+{
+	int ret;
+
+	t7xx_pci_dev_rescan();
+	ret = t7xx_rescan_init();
+	if (ret) {
+		pr_err("Failed to init t7xx rescan work\n");
+		return ret;
+	}
+
+	return pci_register_driver(&t7xx_pci_driver);
+}
+module_init(t7xx_pci_init);
+
+static int t7xx_always_match(struct device *dev, const void *data)
+{
+	return dev->parent->fwnode == data;
+}
+
+static void __exit t7xx_pci_cleanup(void)
+{
+	int remove_flag = 0;
+	struct device *dev;
+
+	dev = driver_find_device(&t7xx_pci_driver.driver, NULL, NULL, t7xx_always_match);
+	if (dev) {
+		pr_debug("unregister t7xx PCIe driver while device is still exist.\n");
+		put_device(dev);
+		remove_flag = 1;
+	} else {
+		pr_debug("no t7xx PCIe driver found.\n");
+	}
+
+	pci_lock_rescan_remove();
+	pci_unregister_driver(&t7xx_pci_driver);
+	pci_unlock_rescan_remove();
+	t7xx_rescan_deinit();
+
+	if (remove_flag) {
+		pr_debug("remove t7xx PCI device\n");
+		pci_stop_and_remove_bus_device_locked(to_pci_dev(dev));
+	}
+}
+
+module_exit(t7xx_pci_cleanup);
 
 MODULE_AUTHOR("MediaTek Inc");
 MODULE_DESCRIPTION("MediaTek PCIe 5G WWAN modem T7xx driver");

drivers/net/wwan/t7xx/t7xx_pci.h

@@ -59,6 +59,7 @@ typedef irqreturn_t (*t7xx_intr_callback)(int irq, void *param);
  * @md_pm_lock: protects PCIe sleep lock
  * @sleep_disable_count: PCIe L1.2 lock counter
  * @sleep_lock_acquire: indicates that sleep has been disabled
+ * @dl: devlink struct
  */
 struct t7xx_pci_dev {
 	t7xx_intr_callback	intr_handler[EXT_INT_NUM];
@@ -69,6 +70,7 @@ struct t7xx_pci_dev {
 	struct t7xx_modem	*md;
 	struct t7xx_ccmni_ctrl	*ccmni_ctlb;
 	bool			rgu_pci_irq_en;
+	bool			hp_enable;
 
 	/* Low Power Items */
 	struct list_head	md_pm_entities;
@@ -78,6 +80,7 @@ struct t7xx_pci_dev {
 	spinlock_t		md_pm_lock;		/* Protects PCI resource lock */
 	unsigned int		sleep_disable_count;
 	struct completion	sleep_lock_acquire;
+	struct t7xx_devlink	*dl;
 };
 
 enum t7xx_pm_id {

drivers/net/wwan/t7xx/t7xx_pci_rescan.c

+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2021, MediaTek Inc.
+ * Copyright (c) 2021-2022, Intel Corporation.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ":t7xx:%s: " fmt, __func__
+#define dev_fmt(fmt) "t7xx: " fmt
+
+#include <linux/delay.h>
+#include <linux/pci.h>
+#include <linux/spinlock.h>
+#include <linux/workqueue.h>
+
+#include "t7xx_pci.h"
+#include "t7xx_pci_rescan.h"
+
+static struct remove_rescan_context g_mtk_rescan_context;
+
+void t7xx_pci_dev_rescan(void)
+{
+	struct pci_bus *b = NULL;
+
+	pci_lock_rescan_remove();
+	while ((b = pci_find_next_bus(b)))
+		pci_rescan_bus(b);
+
+	pci_unlock_rescan_remove();
+}
+
+void t7xx_rescan_done(void)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&g_mtk_rescan_context.dev_lock, flags);
+	if (g_mtk_rescan_context.rescan_done == 0) {
+		pr_debug("this is a rescan probe\n");
+		g_mtk_rescan_context.rescan_done = 1;
+	} else {
+		pr_debug("this is a init probe\n");
+	}
+	spin_unlock_irqrestore(&g_mtk_rescan_context.dev_lock, flags);
+}
+
+static void t7xx_remove_rescan(struct work_struct *work)
+{
+	struct pci_dev *pdev;
+	int num_retries = RESCAN_RETRIES;
+	unsigned long flags;
+
+	spin_lock_irqsave(&g_mtk_rescan_context.dev_lock, flags);
+	g_mtk_rescan_context.rescan_done = 0;
+	pdev = g_mtk_rescan_context.dev;
+	spin_unlock_irqrestore(&g_mtk_rescan_context.dev_lock, flags);
+
+	if (pdev) {
+		pci_stop_and_remove_bus_device_locked(pdev);
+		pr_debug("start remove and rescan flow\n");
+	}
+
+	do {
+		t7xx_pci_dev_rescan();
+		spin_lock_irqsave(&g_mtk_rescan_context.dev_lock, flags);
+		if (g_mtk_rescan_context.rescan_done) {
+			spin_unlock_irqrestore(&g_mtk_rescan_context.dev_lock, flags);
+			break;
+		}
+
+		spin_unlock_irqrestore(&g_mtk_rescan_context.dev_lock, flags);
+		msleep(DELAY_RESCAN_MTIME);
+	} while (num_retries--);
+}
+
+void t7xx_rescan_queue_work(struct pci_dev *pdev)
+{
+	unsigned long flags;
+
+	dev_info(&pdev->dev, "start queue_mtk_rescan_work\n");
+	spin_lock_irqsave(&g_mtk_rescan_context.dev_lock, flags);
+	if (!g_mtk_rescan_context.rescan_done) {
+		dev_err(&pdev->dev, "rescan failed because last rescan undone\n");
+		spin_unlock_irqrestore(&g_mtk_rescan_context.dev_lock, flags);
+		return;
+	}
+
+	g_mtk_rescan_context.dev = pdev;
+	spin_unlock_irqrestore(&g_mtk_rescan_context.dev_lock, flags);
+	queue_work(g_mtk_rescan_context.pcie_rescan_wq, &g_mtk_rescan_context.service_task);
+}
+
+int t7xx_rescan_init(void)
+{
+	spin_lock_init(&g_mtk_rescan_context.dev_lock);
+	g_mtk_rescan_context.rescan_done = 1;
+	g_mtk_rescan_context.dev = NULL;
+	g_mtk_rescan_context.pcie_rescan_wq = create_singlethread_workqueue(MTK_RESCAN_WQ);
+	if (!g_mtk_rescan_context.pcie_rescan_wq) {
+		pr_err("Failed to create workqueue: %s\n", MTK_RESCAN_WQ);
+		return -ENOMEM;
+	}
+
+	INIT_WORK(&g_mtk_rescan_context.service_task, t7xx_remove_rescan);
+
+	return 0;
+}
+
+void t7xx_rescan_deinit(void)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&g_mtk_rescan_context.dev_lock, flags);
+	g_mtk_rescan_context.rescan_done = 0;
+	g_mtk_rescan_context.dev = NULL;
+	spin_unlock_irqrestore(&g_mtk_rescan_context.dev_lock, flags);
+	cancel_work_sync(&g_mtk_rescan_context.service_task);
+	destroy_workqueue(g_mtk_rescan_context.pcie_rescan_wq);
+}

drivers/net/wwan/t7xx/t7xx_pci_rescan.h

+/* SPDX-License-Identifier: GPL-2.0-only
+ *
+ * Copyright (c) 2021, MediaTek Inc.
+ * Copyright (c) 2021-2022, Intel Corporation.
+ */
+
+#ifndef __T7XX_PCI_RESCAN_H__
+#define __T7XX_PCI_RESCAN_H__
+
+#define MTK_RESCAN_WQ "mtk_rescan_wq"
+
+#define DELAY_RESCAN_MTIME 1000
+#define RESCAN_RETRIES 35
+
+struct remove_rescan_context {
+	struct work_struct	 service_task;
+	struct workqueue_struct *pcie_rescan_wq;
+	spinlock_t		dev_lock; /* protects device */
+	struct pci_dev		*dev;
+	int			rescan_done;
+};
+
+void t7xx_pci_dev_rescan(void);
+void t7xx_rescan_queue_work(struct pci_dev *pdev);
+int t7xx_rescan_init(void);
+void t7xx_rescan_deinit(void);
+void t7xx_rescan_done(void);
+
+#endif	/* __T7XX_PCI_RESCAN_H__ */

drivers/net/wwan/t7xx/t7xx_port.h

@@ -36,9 +36,15 @@
 /* Channel ID and Message ID definitions.
  * The channel number consists of peer_id(15:12) , channel_id(11:0)
  * peer_id:
- * 0:reserved, 1: to sAP, 2: to MD
+ * 0:reserved, 1: to AP, 2: to MD
  */
 enum port_ch {
+	/* to AP */
+	PORT_CH_AP_CONTROL_RX = 0x1000,
+	PORT_CH_AP_CONTROL_TX = 0x1001,
+	PORT_CH_AP_LOG_RX = 0x1008,
+	PORT_CH_AP_LOG_TX = 0x1009,
+
 	/* to MD */
 	PORT_CH_CONTROL_RX = 0x2000,
 	PORT_CH_CONTROL_TX = 0x2001,
@@ -94,6 +100,7 @@ struct t7xx_port_conf {
 	struct port_ops		*ops;
 	char			*name;
 	enum wwan_port_type	port_type;
+	bool			is_early_port;
 };
 
 struct t7xx_port {
@@ -122,11 +129,14 @@ struct t7xx_port {
 	int				rx_length_th;
 	bool				chan_enable;
 	struct task_struct		*thread;
+	struct t7xx_devlink	*dl;
 };
 
+int t7xx_get_port_mtu(struct t7xx_port *port);
 struct sk_buff *t7xx_port_alloc_skb(int payload);
 struct sk_buff *t7xx_ctrl_alloc_skb(int payload);
 int t7xx_port_enqueue_skb(struct t7xx_port *port, struct sk_buff *skb);
+int t7xx_port_send_raw_skb(struct t7xx_port *port, struct sk_buff *skb);
 int t7xx_port_send_skb(struct t7xx_port *port, struct sk_buff *skb, unsigned int pkt_header,
 		       unsigned int ex_msg);
 int t7xx_port_send_ctl_skb(struct t7xx_port *port, struct sk_buff *skb, unsigned int msg,

drivers/net/wwan/t7xx/t7xx_port_ctrl_msg.c

@@ -167,8 +167,12 @@ static int control_msg_handler(struct t7xx_port *port, struct sk_buff *skb)
 	case CTL_ID_HS2_MSG:
 		skb_pull(skb, sizeof(*ctrl_msg_h));
 
-		if (port_conf->rx_ch == PORT_CH_CONTROL_RX) {
-			ret = t7xx_fsm_append_event(ctl, FSM_EVENT_MD_HS2, skb->data,
+		if (port_conf->rx_ch == PORT_CH_CONTROL_RX ||
+		    port_conf->rx_ch == PORT_CH_AP_CONTROL_RX) {
+			int event = port_conf->rx_ch == PORT_CH_CONTROL_RX ?
+				    FSM_EVENT_MD_HS2 : FSM_EVENT_AP_HS2;
+
+			ret = t7xx_fsm_append_event(ctl, event, skb->data,
 						    le32_to_cpu(ctrl_msg_h->data_length));
 			if (ret)
 				dev_err(port->dev, "Failed to append Handshake 2 event");

drivers/net/wwan/t7xx/t7xx_port_devlink.c

+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2022, Intel Corporation.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/debugfs.h>
+#include <linux/vmalloc.h>
+
+#include "t7xx_hif_cldma.h"
+#include "t7xx_pci_rescan.h"
+#include "t7xx_port_devlink.h"
+#include "t7xx_port_proxy.h"
+#include "t7xx_state_monitor.h"
+#include "t7xx_uevent.h"
+
+static struct t7xx_devlink_region_info t7xx_devlink_region_list[T7XX_TOTAL_REGIONS] = {
+	{"mr_dump", T7XX_MRDUMP_SIZE},
+	{"lk_dump", T7XX_LKDUMP_SIZE},
+};
+
+static int t7xx_devlink_port_read(struct t7xx_port *port, char *buf, size_t count)
+{
+	int ret = 0, read_len;
+	struct sk_buff *skb;
+
+	spin_lock_irq(&port->rx_wq.lock);
+	if (skb_queue_empty(&port->rx_skb_list)) {
+		ret = wait_event_interruptible_locked_irq(port->rx_wq,
+							  !skb_queue_empty(&port->rx_skb_list));
+		if (ret == -ERESTARTSYS) {
+			spin_unlock_irq(&port->rx_wq.lock);
+			return -EINTR;
+		}
+	}
+	skb = skb_dequeue(&port->rx_skb_list);
+	spin_unlock_irq(&port->rx_wq.lock);
+
+	read_len = count > skb->len ? skb->len : count;
+	memcpy(buf, skb->data, read_len);
+	dev_kfree_skb(skb);
+
+	return ret ? ret : read_len;
+}
+
+static int t7xx_devlink_port_write(struct t7xx_port *port, const char *buf, size_t count)
+{
+	const struct t7xx_port_conf *port_conf = port->port_conf;
+	size_t actual_count;
+	struct sk_buff *skb;
+	int ret, txq_mtu;
+
+	txq_mtu = t7xx_get_port_mtu(port);
+	if (txq_mtu < 0)
+		return -EINVAL;
+
+	actual_count = count > txq_mtu ? txq_mtu : count;
+	skb = __dev_alloc_skb(actual_count, GFP_KERNEL);
+	if (!skb)
+		return -ENOMEM;
+
+	skb_put_data(skb, buf, actual_count);
+	ret = t7xx_port_send_raw_skb(port, skb);
+	if (ret) {
+		dev_err(port->dev, "write error on %s, size: %zu, ret: %d\n",
+			port_conf->name, actual_count, ret);
+		dev_kfree_skb(skb);
+		return ret;
+	}
+
+	return actual_count;
+}
+
+static int t7xx_devlink_fb_handle_response(struct t7xx_port *port, int *data)
+{
+	int ret = 0, index = 0, return_data = 0, read_bytes;
+	char status[T7XX_FB_RESPONSE_SIZE + 1];
+
+	while (index < T7XX_FB_RESP_COUNT) {
+		index++;
+		read_bytes = t7xx_devlink_port_read(port, status, T7XX_FB_RESPONSE_SIZE);
+		if (read_bytes < 0) {
+			dev_err(port->dev, "status read failed");
+			ret = -EIO;
+			break;
+		}
+
+		status[read_bytes] = '\0';
+		if (!strncmp(status, T7XX_FB_RESP_INFO, strlen(T7XX_FB_RESP_INFO))) {
+			break;
+		} else if (!strncmp(status, T7XX_FB_RESP_OKAY, strlen(T7XX_FB_RESP_OKAY))) {
+			break;
+		} else if (!strncmp(status, T7XX_FB_RESP_FAIL, strlen(T7XX_FB_RESP_FAIL))) {
+			ret = -EPROTO;
+			break;
+		} else if (!strncmp(status, T7XX_FB_RESP_DATA, strlen(T7XX_FB_RESP_DATA))) {
+			if (data) {
+				if (!kstrtoint(status + strlen(T7XX_FB_RESP_DATA), 16,
+					       &return_data)) {
+					*data = return_data;
+				} else {
+					dev_err(port->dev, "kstrtoint error!\n");
+					ret = -EPROTO;
+				}
+			}
+			break;
+		}
+	}
+
+	return ret;
+}
+
+static int t7xx_devlink_fb_raw_command(char *cmd, struct t7xx_port *port, int *data)
+{
+	int ret, cmd_size = strlen(cmd);
+
+	if (cmd_size > T7XX_FB_COMMAND_SIZE) {
+		dev_err(port->dev, "command length %d is long\n", cmd_size);
+		return -EINVAL;
+	}
+
+	if (cmd_size != t7xx_devlink_port_write(port, cmd, cmd_size)) {
+		dev_err(port->dev, "raw command = %s write failed\n", cmd);
+		return -EIO;
+	}
+
+	dev_dbg(port->dev, "raw command = %s written to the device\n", cmd);
+	ret = t7xx_devlink_fb_handle_response(port, data);
+	if (ret)
+		dev_err(port->dev, "raw command = %s response FAILURE:%d\n", cmd, ret);
+
+	return ret;
+}
+
+static int t7xx_devlink_fb_send_buffer(struct t7xx_port *port, const u8 *buf, size_t size)
+{
+	size_t remaining = size, offset = 0, len;
+	int write_done;
+
+	if (!size)
+		return -EINVAL;
+
+	while (remaining) {
+		len = min_t(size_t, remaining, CLDMA_DEDICATED_Q_BUFF_SZ);
+		write_done = t7xx_devlink_port_write(port, buf + offset, len);
+
+		if (write_done < 0) {
+			dev_err(port->dev, "write to device failed in %s", __func__);
+			return -EIO;
+		} else if (write_done != len) {
+			dev_err(port->dev, "write Error. Only %d/%zu bytes written",
+				write_done, len);
+			return -EIO;
+		}
+
+		remaining -= len;
+		offset += len;
+	}
+
+	return 0;
+}
+
+static int t7xx_devlink_fb_download_command(struct t7xx_port *port, size_t size)
+{
+	char download_command[T7XX_FB_COMMAND_SIZE];
+
+	snprintf(download_command, sizeof(download_command), "%s:%08zx",
+		 T7XX_FB_CMD_DOWNLOAD, size);
+	return t7xx_devlink_fb_raw_command(download_command, port, NULL);
+}
+
+static int t7xx_devlink_fb_download(struct t7xx_port *port, const u8 *buf, size_t size)
+{
+	int ret;
+
+	if (size <= 0 || size > SIZE_MAX) {
+		dev_err(port->dev, "file is too large to download");
+		return -EINVAL;
+	}
+
+	ret = t7xx_devlink_fb_download_command(port, size);
+	if (ret)
+		return ret;
+
+	ret = t7xx_devlink_fb_send_buffer(port, buf, size);
+	if (ret)
+		return ret;
+
+	return t7xx_devlink_fb_handle_response(port, NULL);
+}
+
+static int t7xx_devlink_fb_flash(const char *cmd, struct t7xx_port *port)
+{
+	char flash_command[T7XX_FB_COMMAND_SIZE];
+
+	snprintf(flash_command, sizeof(flash_command), "%s:%s", T7XX_FB_CMD_FLASH, cmd);
+	return t7xx_devlink_fb_raw_command(flash_command, port, NULL);
+}
+
+static int t7xx_devlink_fb_flash_partition(const char *partition, const u8 *buf,
+					   struct t7xx_port *port, size_t size)
+{
+	int ret;
+
+	ret = t7xx_devlink_fb_download(port, buf, size);
+	if (ret)
+		return ret;
+
+	return t7xx_devlink_fb_flash(partition, port);
+}
+
+static int t7xx_devlink_fb_get_core(struct t7xx_port *port)
+{
+	struct t7xx_devlink_region_info *mrdump_region;
+	char mrdump_complete_event[T7XX_FB_EVENT_SIZE];
+	u32 mrd_mb = T7XX_MRDUMP_SIZE / (1024 * 1024);
+	struct t7xx_devlink *dl = port->dl;
+	int clen, dlen = 0, result = 0;
+	unsigned long long zipsize = 0;
+	char mcmd[T7XX_FB_MCMD_SIZE];
+	size_t offset_dlen = 0;
+	char *mdata;
+
+	set_bit(T7XX_MRDUMP_STATUS, &dl->status);
+	mdata = kmalloc(T7XX_FB_MDATA_SIZE, GFP_KERNEL);
+	if (!mdata) {
+		result = -ENOMEM;
+		goto get_core_exit;
+	}
+
+	mrdump_region = dl->dl_region_info[T7XX_MRDUMP_INDEX];
+	mrdump_region->dump = vmalloc(mrdump_region->default_size);
+	if (!mrdump_region->dump) {
+		kfree(mdata);
+		result = -ENOMEM;
+		goto get_core_exit;
+	}
+
+	result = t7xx_devlink_fb_raw_command(T7XX_FB_CMD_OEM_MRDUMP, port, NULL);
+	if (result) {
+		dev_err(port->dev, "%s command failed\n", T7XX_FB_CMD_OEM_MRDUMP);
+		vfree(mrdump_region->dump);
+		kfree(mdata);
+		goto get_core_exit;
+	}
+
+	while (mrdump_region->default_size > offset_dlen) {
+		clen = t7xx_devlink_port_read(port, mcmd, sizeof(mcmd));
+		if (clen == strlen(T7XX_FB_CMD_RTS) &&
+		    (!strncmp(mcmd, T7XX_FB_CMD_RTS, strlen(T7XX_FB_CMD_RTS)))) {
+			memset(mdata, 0, T7XX_FB_MDATA_SIZE);
+			dlen = 0;
+			memset(mcmd, 0, sizeof(mcmd));
+			clen = snprintf(mcmd, sizeof(mcmd), "%s", T7XX_FB_CMD_CTS);
+
+			if (t7xx_devlink_port_write(port, mcmd, clen) != clen) {
+				dev_err(port->dev, "write for _CTS failed:%d\n", clen);
+				goto get_core_free_mem;
+			}
+
+			dlen = t7xx_devlink_port_read(port, mdata, T7XX_FB_MDATA_SIZE);
+			if (dlen <= 0) {
+				dev_err(port->dev, "read data error(%d)\n", dlen);
+				goto get_core_free_mem;
+			}
+
+			zipsize += (unsigned long long)(dlen);
+			memcpy(mrdump_region->dump + offset_dlen, mdata, dlen);
+			offset_dlen += dlen;
+			memset(mcmd, 0, sizeof(mcmd));
+			clen = snprintf(mcmd, sizeof(mcmd), "%s", T7XX_FB_CMD_FIN);
+			if (t7xx_devlink_port_write(port, mcmd, clen) != clen) {
+				dev_err(port->dev, "%s: _FIN failed, (Read %05d:%05llu)\n",
+					__func__, clen, zipsize);
+				goto get_core_free_mem;
+			}
+		} else if ((clen == strlen(T7XX_FB_RESP_MRDUMP_DONE)) &&
+			  (!strncmp(mcmd, T7XX_FB_RESP_MRDUMP_DONE,
+				    strlen(T7XX_FB_RESP_MRDUMP_DONE)))) {
+			dev_dbg(port->dev, "%s! size:%zd\n", T7XX_FB_RESP_MRDUMP_DONE, offset_dlen);
+			mrdump_region->actual_size = offset_dlen;
+			snprintf(mrdump_complete_event, sizeof(mrdump_complete_event),
+				 "%s size=%zu", T7XX_UEVENT_MRDUMP_READY, offset_dlen);
+			t7xx_uevent_send(dl->dev, mrdump_complete_event);
+			kfree(mdata);
+			result = 0;
+			goto get_core_exit;
+		} else {
+			dev_err(port->dev, "getcore protocol error (read len %05d)\n", clen);
+			goto get_core_free_mem;
+		}
+	}
+
+	dev_err(port->dev, "mrdump exceeds %uMB size. Discarded!", mrd_mb);
+	t7xx_uevent_send(port->dev, T7XX_UEVENT_MRD_DISCD);
+
+get_core_free_mem:
+	kfree(mdata);
+	vfree(mrdump_region->dump);
+	clear_bit(T7XX_MRDUMP_STATUS, &dl->status);
+	return -EPROTO;
+
+get_core_exit:
+	clear_bit(T7XX_MRDUMP_STATUS, &dl->status);
+	return result;
+}
+
+static int t7xx_devlink_fb_dump_log(struct t7xx_port *port)
+{
+	struct t7xx_devlink_region_info *lkdump_region;
+	char lkdump_complete_event[T7XX_FB_EVENT_SIZE];
+	struct t7xx_devlink *dl = port->dl;
+	int dlen, datasize = 0, result;
+	size_t offset_dlen = 0;
+	u8 *data;
+
+	set_bit(T7XX_LKDUMP_STATUS, &dl->status);
+	result = t7xx_devlink_fb_raw_command(T7XX_FB_CMD_OEM_LKDUMP, port, &datasize);
+	if (result) {
+		dev_err(port->dev, "%s command returns failure\n", T7XX_FB_CMD_OEM_LKDUMP);
+		goto lkdump_exit;
+	}
+
+	lkdump_region = dl->dl_region_info[T7XX_LKDUMP_INDEX];
+	if (datasize > lkdump_region->default_size) {
+		dev_err(port->dev, "lkdump size is more than %dKB. Discarded!",
+			T7XX_LKDUMP_SIZE / 1024);
+		t7xx_uevent_send(dl->dev, T7XX_UEVENT_LKD_DISCD);
+		result = -EPROTO;
+		goto lkdump_exit;
+	}
+
+	data = kzalloc(datasize, GFP_KERNEL);
+	if (!data) {
+		result = -ENOMEM;
+		goto lkdump_exit;
+	}
+
+	lkdump_region->dump = vmalloc(lkdump_region->default_size);
+	if (!lkdump_region->dump) {
+		kfree(data);
+		result = -ENOMEM;
+		goto lkdump_exit;
+	}
+
+	while (datasize > 0) {
+		dlen = t7xx_devlink_port_read(port, data, datasize);
+		if (dlen <= 0) {
+			dev_err(port->dev, "lkdump read error ret = %d", dlen);
+			kfree(data);
+			result = -EPROTO;
+			goto lkdump_exit;
+		}
+
+		memcpy(lkdump_region->dump + offset_dlen, data, dlen);
+		datasize -= dlen;
+		offset_dlen += dlen;
+	}
+
+	dev_dbg(port->dev, "LKDUMP DONE! size:%zd\n", offset_dlen);
+	lkdump_region->actual_size = offset_dlen;
+	snprintf(lkdump_complete_event, sizeof(lkdump_complete_event), "%s size=%zu",
+		 T7XX_UEVENT_LKDUMP_READY, offset_dlen);
+	t7xx_uevent_send(dl->dev, lkdump_complete_event);
+	kfree(data);
+	clear_bit(T7XX_LKDUMP_STATUS, &dl->status);
+	return t7xx_devlink_fb_handle_response(port, NULL);
+
+lkdump_exit:
+	clear_bit(T7XX_LKDUMP_STATUS, &dl->status);
+	return result;
+}
+
+static int t7xx_devlink_flash_update(struct devlink *devlink,
+				     struct devlink_flash_update_params *params,
+				     struct netlink_ext_ack *extack)
+{
+	struct t7xx_devlink *dl = devlink_priv(devlink);
+	const char *component = params->component;
+	const struct firmware *fw = params->fw;
+	char flash_event[T7XX_FB_EVENT_SIZE];
+	struct t7xx_port *port;
+	int ret;
+
+	port = dl->port;
+	if (port->dl->mode != T7XX_FB_DL_MODE) {
+		dev_err(port->dev, "Modem is not in fastboot download mode!");
+		ret = -EPERM;
+		goto err_out;
+	}
+
+	if (dl->status != T7XX_DEVLINK_IDLE) {
+		dev_err(port->dev, "Modem is busy!");
+		ret = -EBUSY;
+		goto err_out;
+	}
+
+	if (!component || !fw->data) {
+		ret = -EINVAL;
+		goto err_out;
+	}
+
+	set_bit(T7XX_FLASH_STATUS, &dl->status);
+	dev_dbg(port->dev, "flash partition name:%s binary size:%zu\n", component, fw->size);
+	ret = t7xx_devlink_fb_flash_partition(component, fw->data, port, fw->size);
+	if (ret) {
+		devlink_flash_update_status_notify(devlink, "flashing failure!",
+						   params->component, 0, 0);
+		snprintf(flash_event, sizeof(flash_event), "%s for [%s]",
+			 T7XX_UEVENT_FLASHING_FAILURE, params->component);
+	} else {
+		devlink_flash_update_status_notify(devlink, "flashing success!",
+						   params->component, 0, 0);
+		snprintf(flash_event, sizeof(flash_event), "%s for [%s]",
+			 T7XX_UEVENT_FLASHING_SUCCESS, params->component);
+	}
+
+	t7xx_uevent_send(dl->dev, flash_event);
+
+err_out:
+	clear_bit(T7XX_FLASH_STATUS, &dl->status);
+	return ret;
+}
+
+static int t7xx_devlink_reload_down(struct devlink *devlink, bool netns_change,
+				    enum devlink_reload_action action,
+				    enum devlink_reload_limit limit,
+				    struct netlink_ext_ack *extack)
+{
+	struct t7xx_devlink *dl = devlink_priv(devlink);
+
+	switch (action) {
+	case DEVLINK_RELOAD_ACTION_DRIVER_REINIT:
+		dl->set_fastboot_dl = 1;
+		return 0;
+	case DEVLINK_RELOAD_ACTION_FW_ACTIVATE:
+		return t7xx_devlink_fb_raw_command(T7XX_FB_CMD_REBOOT, dl->port, NULL);
+	default:
+		/* Unsupported action should not get to this function */
+		return -EOPNOTSUPP;
+	}
+}
+
+static int t7xx_devlink_reload_up(struct devlink *devlink,
+				  enum devlink_reload_action action,
+				  enum devlink_reload_limit limit,
+				  u32 *actions_performed,
+				  struct netlink_ext_ack *extack)
+{
+	struct t7xx_devlink *dl = devlink_priv(devlink);
+	*actions_performed = BIT(action);
+	switch (action) {
+	case DEVLINK_RELOAD_ACTION_DRIVER_REINIT:
+	case DEVLINK_RELOAD_ACTION_FW_ACTIVATE:
+		t7xx_rescan_queue_work(dl->mtk_dev->pdev);
+		return 0;
+	default:
+		/* Unsupported action should not get to this function */
+		return -EOPNOTSUPP;
+	}
+}
+
+/* Call back function for devlink ops */
+static const struct devlink_ops devlink_flash_ops = {
+	.supported_flash_update_params = DEVLINK_SUPPORT_FLASH_UPDATE_COMPONENT,
+	.flash_update = t7xx_devlink_flash_update,
+	.reload_actions = BIT(DEVLINK_RELOAD_ACTION_DRIVER_REINIT) |
+			  BIT(DEVLINK_RELOAD_ACTION_FW_ACTIVATE),
+	.reload_down = t7xx_devlink_reload_down,
+	.reload_up = t7xx_devlink_reload_up,
+};
+
+static int t7xx_devlink_region_snapshot(struct devlink *dl, const struct devlink_region_ops *ops,
+					struct netlink_ext_ack *extack, u8 **data)
+{
+	struct t7xx_devlink_region_info *region_info = ops->priv;
+	struct t7xx_devlink *t7xx_dl = devlink_priv(dl);
+	u8 *snapshot_mem;
+
+	if (t7xx_dl->status != T7XX_DEVLINK_IDLE) {
+		dev_err(t7xx_dl->dev, "Modem is busy!");
+		return -EBUSY;
+	}
+
+	dev_dbg(t7xx_dl->dev, "accessed devlink region:%s index:%d", ops->name, region_info->entry);
+	if (!strncmp(ops->name, "mr_dump", strlen("mr_dump"))) {
+		if (!region_info->dump) {
+			dev_err(t7xx_dl->dev, "devlink region:%s dump memory is not valid!",
+				region_info->region_name);
+			return -ENOMEM;
+		}
+
+		snapshot_mem = vmalloc(region_info->default_size);
+		if (!snapshot_mem)
+			return -ENOMEM;
+
+		memcpy(snapshot_mem, region_info->dump, region_info->default_size);
+		*data = snapshot_mem;
+	} else if (!strncmp(ops->name, "lk_dump", strlen("lk_dump"))) {
+		int ret;
+
+		ret = t7xx_devlink_fb_dump_log(t7xx_dl->port);
+		if (ret)
+			return ret;
+
+		*data = region_info->dump;
+	}
+
+	return 0;
+}
+
+/* To create regions for dump files */
+static int t7xx_devlink_create_region(struct t7xx_devlink *dl)
+{
+	struct devlink_region_ops *region_ops;
+	int rc, i;
+
+	region_ops = dl->dl_region_ops;
+	for (i = 0; i < T7XX_TOTAL_REGIONS; i++) {
+		region_ops[i].name = t7xx_devlink_region_list[i].region_name;
+		region_ops[i].snapshot = t7xx_devlink_region_snapshot;
+		region_ops[i].destructor = vfree;
+		dl->dl_region[i] =
+		devlink_region_create(dl->dl_ctx, &region_ops[i], T7XX_MAX_SNAPSHOTS,
+				      t7xx_devlink_region_list[i].default_size);
+
+		if (IS_ERR(dl->dl_region[i])) {
+			rc = PTR_ERR(dl->dl_region[i]);
+			dev_err(dl->dev, "devlink region fail,err %d", rc);
+			for ( ; i >= 0; i--)
+				devlink_region_destroy(dl->dl_region[i]);
+
+			return rc;
+		}
+
+		t7xx_devlink_region_list[i].entry = i;
+		region_ops[i].priv = t7xx_devlink_region_list + i;
+	}
+
+	return 0;
+}
+
+/* To Destroy devlink regions */
+static void t7xx_devlink_destroy_region(struct t7xx_devlink *dl)
+{
+	u8 i;
+
+	for (i = 0; i < T7XX_TOTAL_REGIONS; i++)
+		devlink_region_destroy(dl->dl_region[i]);
+}
+
+int t7xx_devlink_register(struct t7xx_pci_dev *t7xx_dev)
+{
+	struct devlink *dl_ctx;
+
+	dl_ctx = devlink_alloc(&devlink_flash_ops, sizeof(struct t7xx_devlink),
+			       &t7xx_dev->pdev->dev);
+	if (!dl_ctx)
+		return -ENOMEM;
+
+	devlink_set_features(dl_ctx, DEVLINK_F_RELOAD);
+	devlink_register(dl_ctx);
+	t7xx_dev->dl = devlink_priv(dl_ctx);
+	t7xx_dev->dl->dl_ctx = dl_ctx;
+
+	return 0;
+}
+
+void t7xx_devlink_unregister(struct t7xx_pci_dev *t7xx_dev)
+{
+	struct devlink *dl_ctx = priv_to_devlink(t7xx_dev->dl);
+
+	devlink_unregister(dl_ctx);
+	devlink_free(dl_ctx);
+}
+
+/**
+ * t7xx_devlink_region_init - Initialize/register devlink to t7xx driver
+ * @port: Pointer to port structure
+ * @dw: Pointer to devlink work structure
+ * @wq: Pointer to devlink workqueue structure
+ *
+ * Returns: Pointer to t7xx_devlink on success and NULL on failure
+ */
+static struct t7xx_devlink *t7xx_devlink_region_init(struct t7xx_port *port,
+						     struct t7xx_devlink_work *dw,
+						     struct workqueue_struct *wq)
+{
+	struct t7xx_pci_dev *mtk_dev = port->t7xx_dev;
+	struct t7xx_devlink *dl = mtk_dev->dl;
+	int rc, i;
+
+	dl->dl_ctx = mtk_dev->dl->dl_ctx;
+	dl->mtk_dev = mtk_dev;
+	dl->dev = &mtk_dev->pdev->dev;
+	dl->mode = T7XX_FB_NO_MODE;
+	dl->status = T7XX_DEVLINK_IDLE;
+	dl->dl_work = dw;
+	dl->dl_wq = wq;
+	for (i = 0; i < T7XX_TOTAL_REGIONS; i++) {
+		dl->dl_region_info[i] = &t7xx_devlink_region_list[i];
+		dl->dl_region_info[i]->dump = NULL;
+	}
+	dl->port = port;
+	port->dl = dl;
+
+	rc = t7xx_devlink_create_region(dl);
+	if (rc) {
+		dev_err(dl->dev, "devlink region creation failed, rc %d", rc);
+		return NULL;
+	}
+
+	return dl;
+}
+
+/**
+ * t7xx_devlink_region_deinit - To unintialize the devlink from T7XX driver.
+ * @dl:        Devlink instance
+ */
+static void t7xx_devlink_region_deinit(struct t7xx_devlink *dl)
+{
+	dl->mode = T7XX_FB_NO_MODE;
+	t7xx_devlink_destroy_region(dl);
+}
+
+static void t7xx_devlink_work_handler(struct work_struct *data)
+{
+	struct t7xx_devlink_work *dl_work;
+
+	dl_work = container_of(data, struct t7xx_devlink_work, work);
+	t7xx_devlink_fb_get_core(dl_work->port);
+}
+
+static int t7xx_devlink_init(struct t7xx_port *port)
+{
+	struct t7xx_devlink_work *dl_work;
+	struct workqueue_struct *wq;
+
+	dl_work = kmalloc(sizeof(*dl_work), GFP_KERNEL);
+	if (!dl_work)
+		return -ENOMEM;
+
+	wq = create_workqueue("t7xx_devlink");
+	if (!wq) {
+		kfree(dl_work);
+		dev_err(port->dev, "create_workqueue failed\n");
+		return -ENODATA;
+	}
+
+	INIT_WORK(&dl_work->work, t7xx_devlink_work_handler);
+	dl_work->port = port;
+	port->rx_length_th = T7XX_MAX_QUEUE_LENGTH;
+
+	if (!t7xx_devlink_region_init(port, dl_work, wq))
+		return -ENOMEM;
+
+	return 0;
+}
+
+static void t7xx_devlink_uninit(struct t7xx_port *port)
+{
+	struct t7xx_devlink *dl = port->dl;
+	struct sk_buff *skb;
+	unsigned long flags;
+
+	vfree(dl->dl_region_info[T7XX_MRDUMP_INDEX]->dump);
+	if (dl->dl_wq)
+		destroy_workqueue(dl->dl_wq);
+	kfree(dl->dl_work);
+
+	t7xx_devlink_region_deinit(port->dl);
+	spin_lock_irqsave(&port->rx_skb_list.lock, flags);
+	while ((skb = __skb_dequeue(&port->rx_skb_list)) != NULL)
+		dev_kfree_skb(skb);
+	spin_unlock_irqrestore(&port->rx_skb_list.lock, flags);
+}
+
+static int t7xx_devlink_enable_chl(struct t7xx_port *port)
+{
+	spin_lock(&port->port_update_lock);
+	port->chan_enable = true;
+	spin_unlock(&port->port_update_lock);
+
+	if (port->dl->dl_wq && port->dl->mode == T7XX_FB_DUMP_MODE)
+		queue_work(port->dl->dl_wq, &port->dl->dl_work->work);
+
+	return 0;
+}
+
+static int t7xx_devlink_disable_chl(struct t7xx_port *port)
+{
+	spin_lock(&port->port_update_lock);
+	port->chan_enable = false;
+	spin_unlock(&port->port_update_lock);
+
+	return 0;
+}
+
+struct port_ops devlink_port_ops = {
+	.init = &t7xx_devlink_init,
+	.recv_skb = &t7xx_port_enqueue_skb,
+	.uninit = &t7xx_devlink_uninit,
+	.enable_chl = &t7xx_devlink_enable_chl,
+	.disable_chl = &t7xx_devlink_disable_chl,
+};

drivers/net/wwan/t7xx/t7xx_port_devlink.h

+/* SPDX-License-Identifier: GPL-2.0-only
+ *
+ * Copyright (c) 2022, Intel Corporation.
+ */
+
+#ifndef __T7XX_PORT_DEVLINK_H__
+#define __T7XX_PORT_DEVLINK_H__
+
+#include <net/devlink.h>
+
+#include "t7xx_pci.h"
+
+#define T7XX_MAX_QUEUE_LENGTH 32
+#define T7XX_FB_COMMAND_SIZE  64
+#define T7XX_FB_RESPONSE_SIZE 64
+#define T7XX_FB_MCMD_SIZE     64
+#define T7XX_FB_MDATA_SIZE    1024
+#define T7XX_FB_RESP_COUNT    30
+
+#define T7XX_FB_CMD_RTS          "_RTS"
+#define T7XX_FB_CMD_CTS          "_CTS"
+#define T7XX_FB_CMD_FIN          "_FIN"
+#define T7XX_FB_CMD_OEM_MRDUMP   "oem mrdump"
+#define T7XX_FB_CMD_OEM_LKDUMP   "oem dump_pllk_log"
+#define T7XX_FB_CMD_DOWNLOAD     "download"
+#define T7XX_FB_CMD_FLASH        "flash"
+#define T7XX_FB_CMD_REBOOT       "reboot"
+#define T7XX_FB_RESP_MRDUMP_DONE "MRDUMP08_DONE"
+#define T7XX_FB_RESP_OKAY        "OKAY"
+#define T7XX_FB_RESP_FAIL        "FAIL"
+#define T7XX_FB_RESP_DATA        "DATA"
+#define T7XX_FB_RESP_INFO        "INFO"
+
+#define T7XX_FB_EVENT_SIZE      50
+
+#define T7XX_MAX_SNAPSHOTS  1
+#define T7XX_MAX_REGION_NAME_LENGTH 20
+#define T7XX_MRDUMP_SIZE    (160 * 1024 * 1024)
+#define T7XX_LKDUMP_SIZE    (256 * 1024)
+#define T7XX_TOTAL_REGIONS  2
+
+#define T7XX_FLASH_STATUS   0
+#define T7XX_MRDUMP_STATUS  1
+#define T7XX_LKDUMP_STATUS  2
+#define T7XX_DEVLINK_IDLE   0
+
+#define T7XX_FB_NO_MODE     0
+#define T7XX_FB_DL_MODE     1
+#define T7XX_FB_DUMP_MODE   2
+
+#define T7XX_MRDUMP_INDEX   0
+#define T7XX_LKDUMP_INDEX   1
+
+struct t7xx_devlink_work {
+	struct work_struct work;
+	struct t7xx_port *port;
+};
+
+struct t7xx_devlink_region_info {
+	char region_name[T7XX_MAX_REGION_NAME_LENGTH];
+	u32 default_size;
+	u32 actual_size;
+	u32 entry;
+	u8 *dump;
+};
+
+struct t7xx_devlink {
+	struct t7xx_pci_dev *mtk_dev;
+	struct t7xx_port *port;
+	struct device *dev;
+	struct devlink *dl_ctx;
+	struct t7xx_devlink_work *dl_work;
+	struct workqueue_struct *dl_wq;
+	struct t7xx_devlink_region_info *dl_region_info[T7XX_TOTAL_REGIONS];
+	struct devlink_region_ops dl_region_ops[T7XX_TOTAL_REGIONS];
+	struct devlink_region *dl_region[T7XX_TOTAL_REGIONS];
+	u8 mode;
+	unsigned long status;
+	int set_fastboot_dl;
+};
+
+int t7xx_devlink_register(struct t7xx_pci_dev *t7xx_dev);
+void t7xx_devlink_unregister(struct t7xx_pci_dev *t7xx_dev);
+
+#endif /*__T7XX_PORT_DEVLINK_H__*/

drivers/net/wwan/t7xx/t7xx_port_proxy.c

@@ -77,6 +77,29 @@ static const struct t7xx_port_conf t7xx_md_port_conf[] = {
 		.path_id = CLDMA_ID_MD,
 		.ops = &ctl_port_ops,
 		.name = "t7xx_ctrl",
+	}, {
+		.tx_ch = PORT_CH_AP_CONTROL_TX,
+		.rx_ch = PORT_CH_AP_CONTROL_RX,
+		.txq_index = Q_IDX_CTRL,
+		.rxq_index = Q_IDX_CTRL,
+		.path_id = CLDMA_ID_AP,
+		.ops = &ctl_port_ops,
+		.name = "t7xx_ap_ctrl",
+	},
+};
+
+static struct t7xx_port_conf t7xx_early_port_conf[] = {
+	{
+		.tx_ch = 0xffff,
+		.rx_ch = 0xffff,
+		.txq_index = 1,
+		.rxq_index = 1,
+		.txq_exp_index = 1,
+		.rxq_exp_index = 1,
+		.path_id = CLDMA_ID_AP,
+		.is_early_port = true,
+		.ops = &devlink_port_ops,
+		.name = "ttyDUMP",
 	},
 };
 
@@ -194,7 +217,17 @@ int t7xx_port_enqueue_skb(struct t7xx_port *port, struct sk_buff *skb)
 	return 0;
 }
 
-static int t7xx_port_send_raw_skb(struct t7xx_port *port, struct sk_buff *skb)
+int t7xx_get_port_mtu(struct t7xx_port *port)
+{
+	enum cldma_id path_id = port->port_conf->path_id;
+	int tx_qno = t7xx_port_get_queue_no(port);
+	struct cldma_ctrl *md_ctrl;
+
+	md_ctrl = port->t7xx_dev->md->md_ctrl[path_id];
+	return md_ctrl->tx_ring[tx_qno].pkt_size;
+}
+
+int t7xx_port_send_raw_skb(struct t7xx_port *port, struct sk_buff *skb)
 {
 	enum cldma_id path_id = port->port_conf->path_id;
 	struct cldma_ctrl *md_ctrl;
@@ -309,6 +342,26 @@ static void t7xx_proxy_setup_ch_mapping(struct port_proxy *port_prox)
 	}
 }
 
+static int t7xx_port_proxy_recv_skb_from_queue(struct t7xx_pci_dev *t7xx_dev,
+					       struct cldma_queue *queue, struct sk_buff *skb)
+{
+	struct port_proxy *port_prox = t7xx_dev->md->port_prox;
+	const struct t7xx_port_conf *port_conf;
+	struct t7xx_port *port;
+	int ret;
+
+	port = port_prox->ports;
+	port_conf = port->port_conf;
+
+	ret = port_conf->ops->recv_skb(port, skb);
+	if (ret < 0 && ret != -ENOBUFS) {
+		dev_err(port->dev, "drop on RX ch %d, %d\n", port_conf->rx_ch, ret);
+		dev_kfree_skb_any(skb);
+	}
+
+	return ret;
+}
+
 static struct t7xx_port *t7xx_port_proxy_find_port(struct t7xx_pci_dev *t7xx_dev,
 						   struct cldma_queue *queue, u16 channel)
 {
@@ -330,6 +383,22 @@ static struct t7xx_port *t7xx_port_proxy_find_port(struct t7xx_pci_dev *t7xx_dev
 	return NULL;
 }
 
+struct t7xx_port *t7xx_port_proxy_get_port_by_name(struct port_proxy *port_prox, char *port_name)
+{
+	const struct t7xx_port_conf *port_conf;
+	struct t7xx_port *port;
+	int i;
+
+	for_each_proxy_port(i, port, port_prox) {
+		port_conf = port->port_conf;
+
+		if (!strncmp(port_conf->name, port_name, strlen(port_conf->name)))
+			return port;
+	}
+
+	return NULL;
+}
+
 /**
  * t7xx_port_proxy_recv_skb() - Dispatch received skb.
  * @queue: CLDMA queue.
@@ -350,6 +419,9 @@ static int t7xx_port_proxy_recv_skb(struct cldma_queue *queue, struct sk_buff *s
 	u16 seq_num, channel;
 	int ret;
 
+	if (queue->q_type == CLDMA_DEDICATED_Q)
+		return t7xx_port_proxy_recv_skb_from_queue(t7xx_dev, queue, skb);
+
 	channel = FIELD_GET(CCCI_H_CHN_FLD, le32_to_cpu(ccci_h->status));
 	if (t7xx_fsm_get_md_state(ctl) == MD_STATE_INVALID) {
 		dev_err_ratelimited(dev, "Packet drop on channel 0x%x, modem not ready\n", channel);
@@ -364,7 +436,8 @@ static int t7xx_port_proxy_recv_skb(struct cldma_queue *queue, struct sk_buff *s
 
 	seq_num = t7xx_port_next_rx_seq_num(port, ccci_h);
 	port_conf = port->port_conf;
-	skb_pull(skb, sizeof(*ccci_h));
+	if (!port->port_conf->is_early_port)
+		skb_pull(skb, sizeof(*ccci_h));
 
 	ret = port_conf->ops->recv_skb(port, skb);
 	/* Error indicates to try again later */
@@ -416,8 +489,12 @@ static void t7xx_proxy_init_all_ports(struct t7xx_modem *md)
 		if (port_conf->tx_ch == PORT_CH_CONTROL_TX)
 			md->core_md.ctl_port = port;
 
+		if (port_conf->tx_ch == PORT_CH_AP_CONTROL_TX)
+			md->core_ap.ctl_port = port;
+
 		port->t7xx_dev = md->t7xx_dev;
 		port->dev = &md->t7xx_dev->pdev->dev;
+		port->dl = md->t7xx_dev->dl;
 		spin_lock_init(&port->port_update_lock);
 		port->chan_enable = false;
 
@@ -428,26 +505,58 @@ static void t7xx_proxy_init_all_ports(struct t7xx_modem *md)
 	t7xx_proxy_setup_ch_mapping(port_prox);
 }
 
+void t7xx_port_proxy_set_cfg(struct t7xx_modem *md, enum port_cfg_id cfg_id)
+{
+	struct port_proxy *port_prox = md->port_prox;
+	const struct t7xx_port_conf *port_conf;
+	struct device *dev = port_prox->dev;
+	unsigned int port_count;
+	struct t7xx_port *port;
+	int i;
+
+	if (port_prox->cfg_id == cfg_id)
+		return;
+
+	if (port_prox->cfg_id != PORT_CFG_ID_INVALID) {
+		for_each_proxy_port(i, port, port_prox)
+			port->port_conf->ops->uninit(port);
+
+		devm_kfree(dev, port_prox->ports);
+	}
+
+	if (cfg_id == PORT_CFG_ID_EARLY) {
+		port_conf = t7xx_early_port_conf;
+		port_count = ARRAY_SIZE(t7xx_early_port_conf);
+	} else {
+		port_conf = t7xx_md_port_conf;
+		port_count = ARRAY_SIZE(t7xx_md_port_conf);
+	}
+
+	port_prox->ports = devm_kzalloc(dev, sizeof(struct t7xx_port) * port_count, GFP_KERNEL);
+	if (!port_prox->ports)
+		return;
+
+	for (i = 0; i < port_count; i++)
+		port_prox->ports[i].port_conf = &port_conf[i];
+
+	port_prox->cfg_id = cfg_id;
+	port_prox->port_count = port_count;
+	t7xx_proxy_init_all_ports(md);
+}
+
 static int t7xx_proxy_alloc(struct t7xx_modem *md)
 {
-	unsigned int port_count = ARRAY_SIZE(t7xx_md_port_conf);
 	struct device *dev = &md->t7xx_dev->pdev->dev;
 	struct port_proxy *port_prox;
-	int i;
 
-	port_prox = devm_kzalloc(dev, sizeof(*port_prox) + sizeof(struct t7xx_port) * port_count,
-				 GFP_KERNEL);
+	port_prox = devm_kzalloc(dev, sizeof(*port_prox), GFP_KERNEL);
 	if (!port_prox)
 		return -ENOMEM;
 
 	md->port_prox = port_prox;
 	port_prox->dev = dev;
+	t7xx_port_proxy_set_cfg(md, PORT_CFG_ID_EARLY);
 
-	for (i = 0; i < port_count; i++)
-		port_prox->ports[i].port_conf = &t7xx_md_port_conf[i];
-
-	port_prox->port_count = port_count;
-	t7xx_proxy_init_all_ports(md);
 	return 0;
 }
 
@@ -469,6 +578,7 @@ int t7xx_port_proxy_init(struct t7xx_modem *md)
 	if (ret)
 		return ret;
 
+	t7xx_cldma_set_recv_skb(md->md_ctrl[CLDMA_ID_AP], t7xx_port_proxy_recv_skb);
 	t7xx_cldma_set_recv_skb(md->md_ctrl[CLDMA_ID_MD], t7xx_port_proxy_recv_skb);
 	return 0;
 }

drivers/net/wwan/t7xx/t7xx_port_proxy.h

@@ -31,12 +31,19 @@
 #define RX_QUEUE_MAXLEN		32
 #define CTRL_QUEUE_MAXLEN	16
 
+enum port_cfg_id {
+	PORT_CFG_ID_INVALID,
+	PORT_CFG_ID_NORMAL,
+	PORT_CFG_ID_EARLY,
+};
+
 struct port_proxy {
 	int			port_count;
 	struct list_head	rx_ch_ports[PORT_CH_ID_MASK + 1];
 	struct list_head	queue_ports[CLDMA_NUM][MTK_QUEUES];
 	struct device		*dev;
-	struct t7xx_port	ports[];
+	enum port_cfg_id	cfg_id;
+	struct t7xx_port	*ports;
 };
 
 struct ccci_header {
@@ -86,6 +93,7 @@ struct ctrl_msg_header {
 /* Port operations mapping */
 extern struct port_ops wwan_sub_port_ops;
 extern struct port_ops ctl_port_ops;
+extern struct port_ops devlink_port_ops;
 
 void t7xx_port_proxy_reset(struct port_proxy *port_prox);
 void t7xx_port_proxy_uninit(struct port_proxy *port_prox);
@@ -94,5 +102,7 @@ void t7xx_port_proxy_md_status_notify(struct port_proxy *port_prox, unsigned int
 int t7xx_port_enum_msg_handler(struct t7xx_modem *md, void *msg);
 int t7xx_port_proxy_chl_enable_disable(struct port_proxy *port_prox, unsigned int ch_id,
 				       bool en_flag);
+struct t7xx_port *t7xx_port_proxy_get_port_by_name(struct port_proxy *port_prox, char *port_name);
+void t7xx_port_proxy_set_cfg(struct t7xx_modem *md, enum port_cfg_id cfg_id);
 
 #endif /* __T7XX_PORT_PROXY_H__ */

drivers/net/wwan/t7xx/t7xx_port_wwan.c

@@ -54,7 +54,7 @@ static void t7xx_port_ctrl_stop(struct wwan_port *port)
 static int t7xx_port_ctrl_tx(struct wwan_port *port, struct sk_buff *skb)
 {
 	struct t7xx_port *port_private = wwan_port_get_drvdata(port);
-	size_t len, offset, chunk_len = 0, txq_mtu = CLDMA_MTU;
+	size_t len, offset, chunk_len = 0, txq_mtu;
 	const struct t7xx_port_conf *port_conf;
 	struct t7xx_fsm_ctl *ctl;
 	enum md_state md_state;
@@ -72,6 +72,7 @@ static int t7xx_port_ctrl_tx(struct wwan_port *port, struct sk_buff *skb)
 		return -ENODEV;
 	}
 
+	txq_mtu = t7xx_get_port_mtu(port_private);
 	for (offset = 0; offset < len; offset += chunk_len) {
 		struct sk_buff *skb_ccci;
 		int ret;
@@ -155,6 +156,12 @@ static void t7xx_port_wwan_md_state_notify(struct t7xx_port *port, unsigned int
 {
 	const struct t7xx_port_conf *port_conf = port->port_conf;
 
+	if (state == MD_STATE_EXCEPTION) {
+		if (port->wwan_port)
+			wwan_port_txoff(port->wwan_port);
+		return;
+	}
+
 	if (state != MD_STATE_READY)
 		return;
 

drivers/net/wwan/t7xx/t7xx_reg.h

@@ -56,7 +56,7 @@
 #define D2H_INT_RESUME_ACK			BIT(12)
 #define D2H_INT_SUSPEND_ACK_AP			BIT(13)
 #define D2H_INT_RESUME_ACK_AP			BIT(14)
-#define D2H_INT_ASYNC_SAP_HK			BIT(15)
+#define D2H_INT_ASYNC_AP_HK			BIT(15)
 #define D2H_INT_ASYNC_MD_HK			BIT(16)
 
 /* Register base */
@@ -101,11 +101,34 @@ enum t7xx_pm_resume_state {
 	PM_RESUME_REG_STATE_L2_EXP,
 };
 
+enum host_event_e {
+	HOST_EVENT_INIT = 0,
+	FASTBOOT_DL_NOTY = 0x3,
+};
+
 #define T7XX_PCIE_MISC_DEV_STATUS		0x0d1c
-#define MISC_STAGE_MASK				GENMASK(2, 0)
-#define MISC_RESET_TYPE_PLDR			BIT(26)
 #define MISC_RESET_TYPE_FLDR			BIT(27)
-#define LINUX_STAGE				4
+#define MISC_RESET_TYPE_PLDR			BIT(26)
+#define MISC_DEV_STATUS_MASK			GENMASK(15, 0)
+#define LK_EVENT_MASK				GENMASK(11, 8)
+#define HOST_EVENT_MASK			GENMASK(31, 28)
+
+enum lk_event_id {
+	LK_EVENT_NORMAL = 0,
+	LK_EVENT_CREATE_PD_PORT = 1,
+	LK_EVENT_CREATE_POST_DL_PORT = 2,
+	LK_EVENT_RESET = 7,
+};
+
+#define MISC_STAGE_MASK				GENMASK(2, 0)
+
+enum t7xx_device_stage {
+	INIT_STAGE = 0,
+	PRE_BROM_STAGE = 1,
+	POST_BROM_STAGE = 2,
+	LK_STAGE = 3,
+	LINUX_STAGE = 4,
+};
 
 #define T7XX_PCIE_RESOURCE_STATUS		0x0d28
 #define T7XX_PCIE_RESOURCE_STS_MSK		GENMASK(4, 0)

drivers/net/wwan/t7xx/t7xx_state_monitor.c

@@ -35,11 +35,15 @@
 #include "t7xx_hif_cldma.h"
 #include "t7xx_mhccif.h"
 #include "t7xx_modem_ops.h"
+#include "t7xx_netdev.h"
 #include "t7xx_pci.h"
 #include "t7xx_pcie_mac.h"
+#include "t7xx_port_devlink.h"
 #include "t7xx_port_proxy.h"
+#include "t7xx_pci_rescan.h"
 #include "t7xx_reg.h"
 #include "t7xx_state_monitor.h"
+#include "t7xx_uevent.h"
 
 #define FSM_DRM_DISABLE_DELAY_MS		200
 #define FSM_EVENT_POLL_INTERVAL_MS		20
@@ -47,6 +51,10 @@
 #define FSM_MD_EX_PASS_TIMEOUT_MS		45000
 #define FSM_CMD_TIMEOUT_MS			2000
 
+/* As per MTK, AP to MD Handshake time is ~15s*/
+#define DEVICE_STAGE_POLL_INTERVAL_MS		100
+#define DEVICE_STAGE_POLL_COUNT			150
+
 void t7xx_fsm_notifier_register(struct t7xx_modem *md, struct t7xx_fsm_notifier *notifier)
 {
 	struct t7xx_fsm_ctl *ctl = md->fsm_ctl;
@@ -206,6 +214,65 @@ static void fsm_routine_exception(struct t7xx_fsm_ctl *ctl, struct t7xx_fsm_comm
 		fsm_finish_command(ctl, cmd, 0);
 }
 
+static void t7xx_host_event_notify(struct t7xx_modem *md, unsigned int event_id)
+{
+	u32 value;
+
+	value = ioread32(IREG_BASE(md->t7xx_dev) + T7XX_PCIE_MISC_DEV_STATUS);
+	value &= ~HOST_EVENT_MASK;
+	value |= FIELD_PREP(HOST_EVENT_MASK, event_id);
+	iowrite32(value, IREG_BASE(md->t7xx_dev) + T7XX_PCIE_MISC_DEV_STATUS);
+}
+
+static void t7xx_lk_stage_event_handling(struct t7xx_fsm_ctl *ctl, unsigned int dev_status)
+{
+	struct t7xx_modem *md = ctl->md;
+	struct cldma_ctrl *md_ctrl;
+	enum lk_event_id lk_event;
+	struct t7xx_port *port;
+	struct device *dev;
+
+	dev = &md->t7xx_dev->pdev->dev;
+	lk_event = FIELD_GET(LK_EVENT_MASK, dev_status);
+	dev_info(dev, "Device enter next stage from LK stage/n");
+	switch (lk_event) {
+	case LK_EVENT_NORMAL:
+		break;
+
+	case LK_EVENT_CREATE_PD_PORT:
+	case LK_EVENT_CREATE_POST_DL_PORT:
+		md_ctrl = md->md_ctrl[CLDMA_ID_AP];
+		t7xx_cldma_hif_hw_init(md_ctrl);
+		t7xx_cldma_stop(md_ctrl);
+		t7xx_cldma_switch_cfg(md_ctrl, CLDMA_DEDICATED_Q_CFG);
+		dev_info(dev, "creating the ttyDUMP port\n");
+		port = t7xx_port_proxy_get_port_by_name(md->port_prox, "ttyDUMP");
+		if (!port) {
+			dev_err(dev, "ttyDUMP port not found\n");
+			return;
+		}
+
+		if (lk_event == LK_EVENT_CREATE_PD_PORT)
+			port->dl->mode = T7XX_FB_DUMP_MODE;
+		else
+			port->dl->mode = T7XX_FB_DL_MODE;
+		port->port_conf->ops->enable_chl(port);
+		t7xx_cldma_start(md_ctrl);
+		if (lk_event == LK_EVENT_CREATE_PD_PORT)
+			t7xx_uevent_send(dev, T7XX_UEVENT_MODEM_FASTBOOT_DUMP_MODE);
+		else
+			t7xx_uevent_send(dev, T7XX_UEVENT_MODEM_FASTBOOT_DL_MODE);
+		break;
+
+	case LK_EVENT_RESET:
+		break;
+
+	default:
+		dev_err(dev, "Invalid BROM event\n");
+		break;
+	}
+}
+
 static int fsm_stopped_handler(struct t7xx_fsm_ctl *ctl)
 {
 	ctl->curr_state = FSM_STATE_STOPPED;
@@ -243,13 +310,23 @@ static void fsm_routine_stopping(struct t7xx_fsm_ctl *ctl, struct t7xx_fsm_comma
 	t7xx_cldma_stop(md_ctrl);
 
 	if (!ctl->md->rgu_irq_asserted) {
+		if (t7xx_dev->dl->set_fastboot_dl)
+			t7xx_host_event_notify(ctl->md, FASTBOOT_DL_NOTY);
+
 		t7xx_mhccif_h2d_swint_trigger(t7xx_dev, H2D_CH_DRM_DISABLE_AP);
 		/* Wait for the DRM disable to take effect */
 		msleep(FSM_DRM_DISABLE_DELAY_MS);
 
-		err = t7xx_acpi_fldr_func(t7xx_dev);
-		if (err)
+		if (t7xx_dev->dl->set_fastboot_dl) {
+			/* Do not try fldr because device will always wait for
+			 * MHCCIF bit 13 in fastboot download flow.
+			 */
 			t7xx_mhccif_h2d_swint_trigger(t7xx_dev, H2D_CH_DEVICE_RESET);
+		} else {
+			err = t7xx_acpi_fldr_func(t7xx_dev);
+			if (err)
+				t7xx_mhccif_h2d_swint_trigger(t7xx_dev, H2D_CH_DEVICE_RESET);
+		}
 	}
 
 	fsm_finish_command(ctl, cmd, fsm_stopped_handler(ctl));
@@ -272,6 +349,7 @@ static void fsm_routine_ready(struct t7xx_fsm_ctl *ctl)
 
 	ctl->curr_state = FSM_STATE_READY;
 	t7xx_fsm_broadcast_ready_state(ctl);
+	t7xx_uevent_send(&md->t7xx_dev->pdev->dev, T7XX_UEVENT_MODEM_READY);
 	t7xx_md_event_notify(md, FSM_READY);
 }
 
@@ -285,8 +363,9 @@ static int fsm_routine_starting(struct t7xx_fsm_ctl *ctl)
 	t7xx_fsm_broadcast_state(ctl, MD_STATE_WAITING_FOR_HS1);
 	t7xx_md_event_notify(md, FSM_START);
 
-	wait_event_interruptible_timeout(ctl->async_hk_wq, md->core_md.ready || ctl->exp_flg,
-					 HZ * 60);
+	wait_event_interruptible_timeout(ctl->async_hk_wq,
+					 (md->core_md.ready && md->core_ap.ready) ||
+					  ctl->exp_flg, HZ * 60);
 	dev = &md->t7xx_dev->pdev->dev;
 
 	if (ctl->exp_flg)
@@ -297,6 +376,13 @@ static int fsm_routine_starting(struct t7xx_fsm_ctl *ctl)
 		if (md->core_md.handshake_ongoing)
 			t7xx_fsm_append_event(ctl, FSM_EVENT_MD_HS2_EXIT, NULL, 0);
 
+		fsm_routine_exception(ctl, NULL, EXCEPTION_HS_TIMEOUT);
+		return -ETIMEDOUT;
+	} else if (!md->core_ap.ready) {
+		dev_err(dev, "AP handshake timeout\n");
+		if (md->core_ap.handshake_ongoing)
+			t7xx_fsm_append_event(ctl, FSM_EVENT_AP_HS2_EXIT, NULL, 0);
+
 		fsm_routine_exception(ctl, NULL, EXCEPTION_HS_TIMEOUT);
 		return -ETIMEDOUT;
 	}
@@ -309,8 +395,10 @@ static int fsm_routine_starting(struct t7xx_fsm_ctl *ctl)
 static void fsm_routine_start(struct t7xx_fsm_ctl *ctl, struct t7xx_fsm_command *cmd)
 {
 	struct t7xx_modem *md = ctl->md;
+	unsigned int device_stage;
+	struct device *dev;
 	u32 dev_status;
-	int ret;
+	int ret = 0;
 
 	if (!md)
 		return;
@@ -321,22 +409,60 @@ static void fsm_routine_start(struct t7xx_fsm_ctl *ctl, struct t7xx_fsm_command
 		return;
 	}
 
+	dev = &md->t7xx_dev->pdev->dev;
+	dev_status = ioread32(IREG_BASE(md->t7xx_dev) + T7XX_PCIE_MISC_DEV_STATUS);
+	dev_status &= MISC_DEV_STATUS_MASK;
+	dev_dbg(dev, "dev_status = %x modem state = %d\n", dev_status, ctl->md_state);
+
+	if (dev_status == MISC_DEV_STATUS_MASK) {
+		dev_err(dev, "invalid device status\n");
+		ret = -EINVAL;
+		goto finish_command;
+	}
+
 	ctl->curr_state = FSM_STATE_PRE_START;
 	t7xx_md_event_notify(md, FSM_PRE_START);
 
-	ret = read_poll_timeout(ioread32, dev_status,
-				(dev_status & MISC_STAGE_MASK) == LINUX_STAGE, 20000, 2000000,
-				false, IREG_BASE(md->t7xx_dev) + T7XX_PCIE_MISC_DEV_STATUS);
-	if (ret) {
-		struct device *dev = &md->t7xx_dev->pdev->dev;
+	device_stage = FIELD_GET(MISC_STAGE_MASK, dev_status);
+	if (dev_status == ctl->prev_dev_status) {
+		if (ctl->device_stage_check_cnt++ >= DEVICE_STAGE_POLL_COUNT) {
+			dev_err(dev, "Timeout at device stage 0x%x\n", device_stage);
+			ctl->device_stage_check_cnt = 0;
+			ret = -ETIMEDOUT;
+		} else {
+			msleep(DEVICE_STAGE_POLL_INTERVAL_MS);
+			ret = t7xx_fsm_append_cmd(ctl, FSM_CMD_START, 0);
+		}
 
-		fsm_finish_command(ctl, cmd, -ETIMEDOUT);
-		dev_err(dev, "Invalid device status 0x%lx\n", dev_status & MISC_STAGE_MASK);
-		return;
+		goto finish_command;
+	}
+
+	switch (device_stage) {
+	case INIT_STAGE:
+	case PRE_BROM_STAGE:
+	case POST_BROM_STAGE:
+		ret = t7xx_fsm_append_cmd(ctl, FSM_CMD_START, 0);
+		break;
+
+	case LK_STAGE:
+		dev_info(dev, "LK_STAGE Entered");
+		t7xx_lk_stage_event_handling(ctl, dev_status);
+		break;
+
+	case LINUX_STAGE:
+		t7xx_cldma_hif_hw_init(md->md_ctrl[CLDMA_ID_AP]);
+		t7xx_cldma_hif_hw_init(md->md_ctrl[CLDMA_ID_MD]);
+		t7xx_port_proxy_set_cfg(md, PORT_CFG_ID_NORMAL);
+		ret = fsm_routine_starting(ctl);
+		break;
+
+	default:
+		break;
 	}
 
-	t7xx_cldma_hif_hw_init(md->md_ctrl[CLDMA_ID_MD]);
-	fsm_finish_command(ctl, cmd, fsm_routine_starting(ctl));
+finish_command:
+	ctl->prev_dev_status = dev_status;
+	fsm_finish_command(ctl, cmd, ret);
 }
 
 static int fsm_main_thread(void *data)
@@ -507,6 +633,8 @@ void t7xx_fsm_reset(struct t7xx_modem *md)
 	fsm_flush_event_cmd_qs(ctl);
 	ctl->curr_state = FSM_STATE_STOPPED;
 	ctl->exp_flg = false;
+	ctl->prev_dev_status = 0;
+	ctl->device_stage_check_cnt = 0;
 }
 
 int t7xx_fsm_init(struct t7xx_modem *md)

drivers/net/wwan/t7xx/t7xx_state_monitor.h

@@ -38,10 +38,12 @@ enum t7xx_fsm_state {
 enum t7xx_fsm_event_state {
 	FSM_EVENT_INVALID,
 	FSM_EVENT_MD_HS2,
+	FSM_EVENT_AP_HS2,
 	FSM_EVENT_MD_EX,
 	FSM_EVENT_MD_EX_REC_OK,
 	FSM_EVENT_MD_EX_PASS,
 	FSM_EVENT_MD_HS2_EXIT,
+	FSM_EVENT_AP_HS2_EXIT,
 	FSM_EVENT_MAX
 };
 
@@ -94,6 +96,8 @@ struct t7xx_fsm_ctl {
 	bool			exp_flg;
 	spinlock_t		notifier_lock;		/* Protects notifier list */
 	struct list_head	notifier_list;
+	u32                     prev_dev_status;
+	unsigned int		device_stage_check_cnt;
 };
 
 struct t7xx_fsm_event {

drivers/net/wwan/t7xx/t7xx_uevent.c

+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2022, Intel Corporation.
+ */
+
+#include <linux/slab.h>
+
+#include "t7xx_uevent.h"
+
+/* Update the uevent in work queue context */
+static void t7xx_uevent_work(struct work_struct *data)
+{
+	struct t7xx_uevent_info *info;
+	char *envp[2] = { NULL, NULL };
+
+	info = container_of(data, struct t7xx_uevent_info, work);
+	envp[0] = info->uevent;
+
+	if (kobject_uevent_env(&info->dev->kobj, KOBJ_CHANGE, envp))
+		pr_err("uevent %s failed to sent", info->uevent);
+
+	kfree(info);
+}
+
+/**
+ * t7xx_uevent_send - Send modem event to user space.
+ * @dev:	Generic device pointer
+ * @uevent:	Uevent information
+ */
+void t7xx_uevent_send(struct device *dev, char *uevent)
+{
+	struct t7xx_uevent_info *info = kzalloc(sizeof(*info), GFP_ATOMIC);
+
+	if (!info)
+		return;
+
+	INIT_WORK(&info->work, t7xx_uevent_work);
+	info->dev = dev;
+	snprintf(info->uevent, T7XX_MAX_UEVENT_LEN, "T7XX_EVENT=%s", uevent);
+	schedule_work(&info->work);
+}

drivers/net/wwan/t7xx/t7xx_uevent.h

+/* SPDX-License-Identifier: GPL-2.0-only
+ *
+ * Copyright (c) 2022, Intel Corporation.
+ */
+
+#ifndef __T7XX_UEVENT_H__
+#define __T7XX_UEVENT_H__
+
+#include <linux/device.h>
+#include <linux/kobject.h>
+
+/* Maximum length of user events */
+#define T7XX_MAX_UEVENT_LEN 64
+
+/* T7XX Host driver uevents */
+#define T7XX_UEVENT_MODEM_READY			"T7XX_MODEM_READY"
+#define T7XX_UEVENT_MODEM_FASTBOOT_DL_MODE	"T7XX_MODEM_FASTBOOT_DL_MODE"
+#define T7XX_UEVENT_MODEM_FASTBOOT_DUMP_MODE	"T7XX_MODEM_FASTBOOT_DUMP_MODE"
+#define T7XX_UEVENT_MRDUMP_READY		"T7XX_MRDUMP_READY"
+#define T7XX_UEVENT_LKDUMP_READY		"T7XX_LKDUMP_READY"
+#define T7XX_UEVENT_MRD_DISCD			"T7XX_MRDUMP_DISCARDED"
+#define T7XX_UEVENT_LKD_DISCD			"T7XX_LKDUMP_DISCARDED"
+#define T7XX_UEVENT_FLASHING_SUCCESS		"T7XX_FLASHING_SUCCESS"
+#define T7XX_UEVENT_FLASHING_FAILURE		"T7XX_FLASHING_FAILURE"
+
+/**
+ * struct t7xx_uevent_info - Uevent information structure.
+ * @dev:	Pointer to device structure
+ * @uevent:	Uevent information
+ * @work:	Uevent work struct
+ */
+struct t7xx_uevent_info {
+	struct device *dev;
+	char uevent[T7XX_MAX_UEVENT_LEN];
+	struct work_struct work;
+};
+
+void t7xx_uevent_send(struct device *dev, char *uevent);
+#endif