platform/x86: intel_pmc_ipc: Convert to MFD

This driver only creates a bunch of platform devices sharing resources
belonging to the PMC device. This is pretty much what MFD subsystem is
for so move the driver there, renaming it to intel_pmc_bxt.c which
should be more clear what it is.

MFD subsystem provides nice helper APIs for subdevice creation so
convert the driver to use those. Unfortunately the ACPI device includes
separate resources for most of the subdevices so we cannot simply call
mfd_add_devices() to create all of them but instead we need to call it
separately for each device.

The new MFD driver continues to expose two sysfs attributes that allow
userspace to send IPC commands to the PMC/SCU to avoid breaking any
existing applications that may use these. Generally this is bad idea so
document this in the ABI documentation.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

Documentation/ABI/obsolete/sysfs-driver-intel_pmc_bxt

+These files allow sending arbitrary IPC commands to the PMC/SCU which
+may be dangerous. These will be removed eventually and should not be
+used in any new applications.
+
+What:		/sys/bus/platform/devices/INT34D2:00/simplecmd
+Date:		Jun 2015
+KernelVersion:	4.1
+Contact:	Mika Westerberg <mika.westerberg@linux.intel.com>
+Description:	This interface allows userspace to send an arbitrary
+		IPC command to the PMC/SCU.
+
+		Format: %d %d where first number is command and
+		second number is subcommand.
+
+What:		/sys/bus/platform/devices/INT34D2:00/northpeak
+Date:		Jun 2015
+KernelVersion:	4.1
+Contact:	Mika Westerberg <mika.westerberg@linux.intel.com>
+Description:	This interface allows userspace to enable and disable
+		Northpeak through the PMC/SCU.
+
+		Format: %u.

arch/x86/include/asm/intel_pmc_ipc.h

-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_X86_INTEL_PMC_IPC_H_
-#define  _ASM_X86_INTEL_PMC_IPC_H_
-
-/* Commands */
-#define PMC_IPC_USB_PWR_CTRL		0xF0
-#define PMC_IPC_PMIC_BLACKLIST_SEL	0xEF
-#define PMC_IPC_PHY_CONFIG		0xEE
-#define PMC_IPC_NORTHPEAK_CTRL		0xED
-#define PMC_IPC_PM_DEBUG		0xEC
-#define PMC_IPC_PMC_FW_MSG_CTRL		0xEA
-
-/* IPC return code */
-#define IPC_ERR_NONE			0
-#define IPC_ERR_CMD_NOT_SUPPORTED	1
-#define IPC_ERR_CMD_NOT_SERVICED	2
-#define IPC_ERR_UNABLE_TO_SERVICE	3
-#define IPC_ERR_CMD_INVALID		4
-#define IPC_ERR_CMD_FAILED		5
-#define IPC_ERR_EMSECURITY		6
-#define IPC_ERR_UNSIGNEDKERNEL		7
-
-/* GCR reg offsets from gcr base*/
-#define PMC_GCR_PMC_CFG_REG		0x08
-#define PMC_GCR_TELEM_DEEP_S0IX_REG	0x78
-#define PMC_GCR_TELEM_SHLW_S0IX_REG	0x80
-
-#if IS_ENABLED(CONFIG_INTEL_PMC_IPC)
-
-int intel_pmc_s0ix_counter_read(u64 *data);
-int intel_pmc_gcr_read64(u32 offset, u64 *data);
-
-#else
-
-static inline int intel_pmc_s0ix_counter_read(u64 *data)
-{
-	return -EINVAL;
-}
-
-static inline int intel_pmc_gcr_read64(u32 offset, u64 *data)
-{
-	return -EINVAL;
-}
-
-#endif /*CONFIG_INTEL_PMC_IPC*/
-
-#endif

arch/x86/include/asm/intel_telemetry.h

@@ -53,6 +53,7 @@ struct telemetry_plt_config {
 	struct telemetry_unit_config ioss_config;
 	struct mutex telem_trace_lock;
 	struct mutex telem_lock;
+	struct intel_pmc_dev *pmc;
 	struct intel_scu_ipc_dev *scu;
 	bool telem_in_use;
 };

drivers/mfd/Kconfig

@@ -551,7 +551,7 @@ config INTEL_SOC_PMIC
 
 config INTEL_SOC_PMIC_BXTWC
 	tristate "Support for Intel Broxton Whiskey Cove PMIC"
-	depends on INTEL_PMC_IPC
+	depends on MFD_INTEL_PMC_BXT
 	select MFD_CORE
 	select REGMAP_IRQ
 	help
@@ -632,6 +632,20 @@ config MFD_INTEL_MSIC
 	  Passage) chip. This chip embeds audio, battery, GPIO, etc.
 	  devices used in Intel Medfield platforms.
 
+config MFD_INTEL_PMC_BXT
+	tristate "Intel PMC Driver for Broxton"
+	depends on X86
+	depends on X86_PLATFORM_DEVICES
+	depends on ACPI
+	select INTEL_SCU_IPC
+	select MFD_CORE
+	help
+	  This driver provides support for the PMC (Power Management
+	  Controller) on Intel Broxton and Apollo Lake. The PMC is a
+	  multi-function device that exposes IPC, General Control
+	  Register and P-unit access. In addition this creates devices
+	  for iTCO watchdog and telemetry that are part of the PMC.
+
 config MFD_IPAQ_MICRO
 	bool "Atmel Micro ASIC (iPAQ h3100/h3600/h3700) Support"
 	depends on SA1100_H3100 || SA1100_H3600

drivers/mfd/Makefile

@@ -212,6 +212,7 @@ obj-$(CONFIG_MFD_INTEL_LPSS)	+= intel-lpss.o
 obj-$(CONFIG_MFD_INTEL_LPSS_PCI)	+= intel-lpss-pci.o
 obj-$(CONFIG_MFD_INTEL_LPSS_ACPI)	+= intel-lpss-acpi.o
 obj-$(CONFIG_MFD_INTEL_MSIC)	+= intel_msic.o
+obj-$(CONFIG_MFD_INTEL_PMC_BXT)	+= intel_pmc_bxt.o
 obj-$(CONFIG_MFD_PALMAS)	+= palmas.o
 obj-$(CONFIG_MFD_VIPERBOARD)    += viperboard.o
 obj-$(CONFIG_MFD_RC5T583)	+= rc5t583.o rc5t583-irq.o

drivers/platform/x86/Kconfig

@@ -1269,7 +1269,8 @@ config INTEL_UNCORE_FREQ_CONTROL
 config INTEL_BXTWC_PMIC_TMU
 	tristate "Intel BXT Whiskey Cove TMU Driver"
 	depends on REGMAP
-	depends on INTEL_SOC_PMIC_BXTWC && INTEL_PMC_IPC
+	depends on MFD_INTEL_PMC_BXT
+	depends on INTEL_SOC_PMIC_BXTWC
 	---help---
 	  Select this driver to use Intel BXT Whiskey Cove PMIC TMU feature.
 	  This driver enables the alarm wakeup functionality in the TMU unit
@@ -1327,15 +1328,6 @@ config INTEL_PMC_CORE
 		- LTR Ignore
 		- MPHY/PLL gating status (Sunrisepoint PCH only)
 
-config INTEL_PMC_IPC
-	tristate "Intel PMC IPC Driver"
-	depends on ACPI
-	select INTEL_SCU_IPC
-	---help---
-	This driver provides support for PMC control on some Intel platforms.
-	The PMC is an ARC processor which defines IPC commands for communication
-	with other entities in the CPU.
-
 config INTEL_PUNIT_IPC
 	tristate "Intel P-Unit IPC Driver"
 	---help---
@@ -1374,7 +1366,9 @@ config INTEL_SCU_IPC_UTIL
 
 config INTEL_TELEMETRY
 	tristate "Intel SoC Telemetry Driver"
-	depends on INTEL_PMC_IPC && INTEL_PUNIT_IPC && X86_64
+	depends on X86_64
+	depends on MFD_INTEL_PMC_BXT
+	depends on INTEL_PUNIT_IPC
 	---help---
 	  This driver provides interfaces to configure and use
 	  telemetry for INTEL SoC from APL onwards. It is also

drivers/platform/x86/Makefile

@@ -138,7 +138,6 @@ obj-$(CONFIG_INTEL_MFLD_THERMAL)	+= intel_mid_thermal.o
 obj-$(CONFIG_INTEL_MID_POWER_BUTTON)	+= intel_mid_powerbtn.o
 obj-$(CONFIG_INTEL_MRFLD_PWRBTN)	+= intel_mrfld_pwrbtn.o
 obj-$(CONFIG_INTEL_PMC_CORE)		+= intel_pmc_core.o intel_pmc_core_pltdrv.o
-obj-$(CONFIG_INTEL_PMC_IPC)		+= intel_pmc_ipc.o
 obj-$(CONFIG_INTEL_PUNIT_IPC)		+= intel_punit_ipc.o
 obj-$(CONFIG_INTEL_SCU_IPC)		+= intel_scu_ipc.o
 obj-$(CONFIG_INTEL_SCU_PCI)		+= intel_scu_pcidrv.o

drivers/platform/x86/intel_telemetry_debugfs.c

@@ -15,6 +15,7 @@
  */
 #include <linux/debugfs.h>
 #include <linux/device.h>
+#include <linux/mfd/intel_pmc_bxt.h>
 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/seq_file.h>
@@ -22,7 +23,6 @@
 
 #include <asm/cpu_device_id.h>
 #include <asm/intel-family.h>
-#include <asm/intel_pmc_ipc.h>
 #include <asm/intel_telemetry.h>
 
 #define DRIVER_NAME			"telemetry_soc_debugfs"
@@ -647,10 +647,11 @@ DEFINE_SHOW_ATTRIBUTE(telem_soc_states);
 
 static int telem_s0ix_res_get(void *data, u64 *val)
 {
+	struct telemetry_plt_config *plt_config = telemetry_get_pltdata();
 	u64 s0ix_total_res;
 	int ret;
 
-	ret = intel_pmc_s0ix_counter_read(&s0ix_total_res);
+	ret = intel_pmc_s0ix_counter_read(plt_config->pmc, &s0ix_total_res);
 	if (ret) {
 		pr_err("Failed to read S0ix residency");
 		return ret;
@@ -837,12 +838,15 @@ static int pm_suspend_exit_cb(void)
 	 */
 	if (suspend_shlw_ctr_exit == suspend_shlw_ctr_temp &&
 	    suspend_deep_ctr_exit == suspend_deep_ctr_temp) {
-		ret = intel_pmc_gcr_read64(PMC_GCR_TELEM_SHLW_S0IX_REG,
+		struct telemetry_plt_config *plt_config = telemetry_get_pltdata();
+		struct intel_pmc_dev *pmc = plt_config->pmc;
+
+		ret = intel_pmc_gcr_read64(pmc, PMC_GCR_TELEM_SHLW_S0IX_REG,
 					  &suspend_shlw_res_exit);
 		if (ret < 0)
 			goto out;
 
-		ret = intel_pmc_gcr_read64(PMC_GCR_TELEM_DEEP_S0IX_REG,
+		ret = intel_pmc_gcr_read64(pmc, PMC_GCR_TELEM_DEEP_S0IX_REG,
 					  &suspend_deep_res_exit);
 		if (ret < 0)
 			goto out;

drivers/platform/x86/intel_telemetry_pltdrv.c

@@ -1115,6 +1115,8 @@ static int telemetry_pltdrv_probe(struct platform_device *pdev)
 
 	telm_conf = (struct telemetry_plt_config *)id->driver_data;
 
+	telm_conf->pmc = dev_get_drvdata(pdev->dev.parent);
+
 	mem = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(mem))
 		return PTR_ERR(mem);

drivers/usb/typec/tcpm/Kconfig

@@ -41,8 +41,8 @@ config TYPEC_FUSB302
 config TYPEC_WCOVE
 	tristate "Intel WhiskeyCove PMIC USB Type-C PHY driver"
 	depends on ACPI
+	depends on MFD_INTEL_PMC_BXT
 	depends on INTEL_SOC_PMIC
-	depends on INTEL_PMC_IPC
 	depends on BXT_WC_PMIC_OPREGION
 	help
 	  This driver adds support for USB Type-C on Intel Broxton platforms

drivers/watchdog/iTCO_wdt.c

@@ -64,6 +64,7 @@
 #include <linux/uaccess.h>		/* For copy_to_user/put_user/... */
 #include <linux/io.h>			/* For inb/outb/... */
 #include <linux/platform_data/itco_wdt.h>
+#include <linux/mfd/intel_pmc_bxt.h>
 
 #include "iTCO_vendor.h"
 
@@ -233,12 +234,24 @@ static int update_no_reboot_bit_cnt(void *priv, bool set)
 	return val != newval ? -EIO : 0;
 }
 
+static int update_no_reboot_bit_pmc(void *priv, bool set)
+{
+	struct intel_pmc_dev *pmc = priv;
+	u32 bits = PMC_CFG_NO_REBOOT_EN;
+	u32 value = set ? bits : 0;
+
+	return intel_pmc_gcr_update(pmc, PMC_GCR_PMC_CFG_REG, bits, value);
+}
+
 static void iTCO_wdt_no_reboot_bit_setup(struct iTCO_wdt_private *p,
-		struct itco_wdt_platform_data *pdata)
+					 struct platform_device *pdev,
+					 struct itco_wdt_platform_data *pdata)
 {
-	if (pdata->update_no_reboot_bit) {
-		p->update_no_reboot_bit = pdata->update_no_reboot_bit;
-		p->no_reboot_priv = pdata->no_reboot_priv;
+	if (pdata->no_reboot_use_pmc) {
+		struct intel_pmc_dev *pmc = dev_get_drvdata(pdev->dev.parent);
+
+		p->update_no_reboot_bit = update_no_reboot_bit_pmc;
+		p->no_reboot_priv = pmc;
 		return;
 	}
 
@@ -478,14 +491,14 @@ static int iTCO_wdt_probe(struct platform_device *pdev)
 		return -ENODEV;
 	}
 
-	iTCO_wdt_no_reboot_bit_setup(p, pdata);
+	iTCO_wdt_no_reboot_bit_setup(p, pdev, pdata);
 
 	/*
 	 * Get the Memory-Mapped GCS or PMC register, we need it for the
 	 * NO_REBOOT flag (TCO v2 and v3).
 	 */
 	if (p->iTCO_version >= 2 && p->iTCO_version < 6 &&
-	    !pdata->update_no_reboot_bit) {
+	    !pdata->no_reboot_use_pmc) {
 		p->gcs_pmc_res = platform_get_resource(pdev,
 						       IORESOURCE_MEM,
 						       ICH_RES_MEM_GCS_PMC);

include/linux/mfd/intel_pmc_bxt.h

+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef MFD_INTEL_PMC_BXT_H
+#define MFD_INTEL_PMC_BXT_H
+
+/* GCR reg offsets from GCR base */
+#define PMC_GCR_PMC_CFG_REG		0x08
+#define PMC_GCR_TELEM_DEEP_S0IX_REG	0x78
+#define PMC_GCR_TELEM_SHLW_S0IX_REG	0x80
+
+/* PMC_CFG_REG bit masks */
+#define PMC_CFG_NO_REBOOT_EN		BIT(4)
+
+/**
+ * struct intel_pmc_dev - Intel PMC device structure
+ * @dev: Pointer to the parent PMC device
+ * @scu: Pointer to the SCU IPC device data structure
+ * @gcr_mem_base: Virtual base address of GCR (Global Configuration Registers)
+ * @gcr_lock: Lock used to serialize access to GCR registers
+ * @telem_base: Pointer to telemetry SSRAM base resource or %NULL if not
+ *		available
+ */
+struct intel_pmc_dev {
+	struct device *dev;
+	struct intel_scu_ipc_dev *scu;
+	void __iomem *gcr_mem_base;
+	spinlock_t gcr_lock;
+	struct resource *telem_base;
+};
+
+#if IS_ENABLED(CONFIG_MFD_INTEL_PMC_BXT)
+int intel_pmc_gcr_read64(struct intel_pmc_dev *pmc, u32 offset, u64 *data);
+int intel_pmc_gcr_update(struct intel_pmc_dev *pmc, u32 offset, u32 mask, u32 val);
+int intel_pmc_s0ix_counter_read(struct intel_pmc_dev *pmc, u64 *data);
+#else
+static inline int intel_pmc_gcr_read64(struct intel_pmc_dev *pmc, u32 offset,
+				       u64 *data)
+{
+	return -ENOTSUPP;
+}
+
+static inline int intel_pmc_gcr_update(struct intel_pmc_dev *pmc, u32 offset,
+				       u32 mask, u32 val)
+{
+	return -ENOTSUPP;
+}
+
+static inline int intel_pmc_s0ix_counter_read(struct intel_pmc_dev *pmc, u64 *data)
+{
+	return -ENOTSUPP;
+}
+#endif
+
+#endif /* MFD_INTEL_PMC_BXT_H */

include/linux/platform_data/itco_wdt.h

@@ -12,13 +12,16 @@
 #define ICH_RES_MEM_OFF		2
 #define ICH_RES_MEM_GCS_PMC	0
 
+/**
+ * struct itco_wdt_platform_data - iTCO_wdt platform data
+ * @name: Name of the platform
+ * @version: iTCO version
+ * @no_reboot_use_pmc: Use PMC BXT API to set and clear NO_REBOOT bit
+ */
 struct itco_wdt_platform_data {
 	char name[32];
 	unsigned int version;
-	/* private data to be passed to update_no_reboot_bit API */
-	void *no_reboot_priv;
-	/* pointer for platform specific no reboot update function */
-	int (*update_no_reboot_bit)(void *priv, bool set);
+	bool no_reboot_use_pmc;
 };
 
 #endif /* _ITCO_WDT_H_ */