intel_mid: Add Mrst & Mfld DMA Drivers

This patch add DMA drivers for DMA controllers in Langwell chipset
of Intel(R) Moorestown platform and DMA controllers in Penwell of
Intel(R) Medfield platfrom

This patch adds support for Moorestown DMAC1 and DMAC2 controllers.
It also add support for Medfiled GP DMA and DMAC1 controllers.
These controllers supports memory to peripheral and peripheral to
memory transfers. It support only single block transfers.

This driver is based on Kernel DMA engine
Anyone who wishes to use this controller should use DMA engine APIs

This controller exposes DMA_SLAVE capabilities and notifies the client drivers
of DMA transaction completion

Config option required to be enabled CONFIG_INTEL_MID_DMAC=y
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

drivers/dma/Kconfig

@@ -33,6 +33,19 @@ if DMADEVICES
 
 comment "DMA Devices"
 
+config INTEL_MID_DMAC
+	tristate "Intel MID DMA support for Peripheral DMA controllers"
+	depends on PCI && X86
+	select DMA_ENGINE
+	default n
+	help
+	  Enable support for the Intel(R) MID DMA engine present
+	  in Intel MID chipsets.
+
+	  Say Y here if you have such a chipset.
+
+	  If unsure, say N.
+
 config ASYNC_TX_DISABLE_CHANNEL_SWITCH
 	bool
 

drivers/dma/Makefile

@@ -7,6 +7,7 @@ endif
 
 obj-$(CONFIG_DMA_ENGINE) += dmaengine.o
 obj-$(CONFIG_NET_DMA) += iovlock.o
+obj-$(CONFIG_INTEL_MID_DMAC) += intel_mid_dma.o
 obj-$(CONFIG_DMATEST) += dmatest.o
 obj-$(CONFIG_INTEL_IOATDMA) += ioat/
 obj-$(CONFIG_INTEL_IOP_ADMA) += iop-adma.o

drivers/dma/intel_mid_dma_regs.h

+/*
+ *  intel_mid_dma_regs.h - Intel MID DMA Drivers
+ *
+ *  Copyright (C) 2008-10 Intel Corp
+ *  Author: Vinod Koul <vinod.koul@intel.com>
+ *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; version 2 of the License.
+ *
+ *  This program is distributed in the hope that it will be useful, but
+ *  WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ *
+ */
+#ifndef __INTEL_MID_DMAC_REGS_H__
+#define __INTEL_MID_DMAC_REGS_H__
+
+#include <linux/dmaengine.h>
+#include <linux/dmapool.h>
+#include <linux/pci_ids.h>
+
+#define INTEL_MID_DMA_DRIVER_VERSION "1.0.5"
+
+#define	REG_BIT0		0x00000001
+#define	REG_BIT8		0x00000100
+
+#define UNMASK_INTR_REG(chan_num) \
+	((REG_BIT0 << chan_num) | (REG_BIT8 << chan_num))
+#define MASK_INTR_REG(chan_num) (REG_BIT8 << chan_num)
+
+#define ENABLE_CHANNEL(chan_num) \
+	((REG_BIT0 << chan_num) | (REG_BIT8 << chan_num))
+
+#define DESCS_PER_CHANNEL	16
+/*DMA Registers*/
+/*registers associated with channel programming*/
+#define DMA_REG_SIZE		0x400
+#define DMA_CH_SIZE		0x58
+
+/*CH X REG = (DMA_CH_SIZE)*CH_NO + REG*/
+#define SAR			0x00 /* Source Address Register*/
+#define DAR			0x08 /* Destination Address Register*/
+#define CTL_LOW			0x18 /* Control Register*/
+#define CTL_HIGH		0x1C /* Control Register*/
+#define CFG_LOW			0x40 /* Configuration Register Low*/
+#define CFG_HIGH		0x44 /* Configuration Register high*/
+
+#define STATUS_TFR		0x2E8
+#define STATUS_BLOCK		0x2F0
+#define STATUS_ERR		0x308
+
+#define RAW_TFR			0x2C0
+#define RAW_BLOCK		0x2C8
+#define RAW_ERR			0x2E0
+
+#define MASK_TFR		0x310
+#define MASK_BLOCK		0x318
+#define MASK_SRC_TRAN		0x320
+#define MASK_DST_TRAN		0x328
+#define MASK_ERR		0x330
+
+#define CLEAR_TFR		0x338
+#define CLEAR_BLOCK		0x340
+#define CLEAR_SRC_TRAN		0x348
+#define CLEAR_DST_TRAN		0x350
+#define CLEAR_ERR		0x358
+
+#define INTR_STATUS		0x360
+#define DMA_CFG			0x398
+#define DMA_CHAN_EN		0x3A0
+
+/*DMA channel control registers*/
+union intel_mid_dma_ctl_lo {
+	struct {
+		u32	int_en:1;	/*enable or disable interrupts*/
+					/*should be 0*/
+		u32	dst_tr_width:3;	/*destination transfer width*/
+					/*usually 32 bits = 010*/
+		u32	src_tr_width:3; /*source transfer width*/
+					/*usually 32 bits = 010*/
+		u32	dinc:2;		/*destination address inc/dec*/
+					/*For mem:INC=00, Periphral NoINC=11*/
+		u32	sinc:2;		/*source address inc or dec, as above*/
+		u32	dst_msize:3;	/*destination burst transaction length*/
+					/*always = 16 ie 011*/
+		u32	src_msize:3;	/*source burst transaction length*/
+					/*always = 16 ie 011*/
+		u32	reser1:3;
+		u32	tt_fc:3;	/*transfer type and flow controller*/
+					/*M-M = 000
+					  P-M = 010
+					  M-P = 001*/
+		u32	dms:2;		/*destination master select = 0*/
+		u32	sms:2;		/*source master select = 0*/
+		u32	llp_dst_en:1;	/*enable/disable destination LLP = 0*/
+		u32	llp_src_en:1;	/*enable/disable source LLP = 0*/
+		u32	reser2:3;
+	} ctlx;
+	u32	ctl_lo;
+};
+
+union intel_mid_dma_ctl_hi {
+	struct {
+		u32	block_ts:12;	/*block transfer size*/
+					/*configured by DMAC*/
+		u32	reser:20;
+	} ctlx;
+	u32	ctl_hi;
+
+};
+
+/*DMA channel configuration registers*/
+union intel_mid_dma_cfg_lo {
+	struct {
+		u32	reser1:5;
+		u32	ch_prior:3;	/*channel priority = 0*/
+		u32	ch_susp:1;	/*channel suspend = 0*/
+		u32	fifo_empty:1;	/*FIFO empty or not R bit = 0*/
+		u32	hs_sel_dst:1;	/*select HW/SW destn handshaking*/
+					/*HW = 0, SW = 1*/
+		u32	hs_sel_src:1;	/*select HW/SW src handshaking*/
+		u32	reser2:6;
+		u32	dst_hs_pol:1;	/*dest HS interface polarity*/
+		u32	src_hs_pol:1;	/*src HS interface polarity*/
+		u32	max_abrst:10;	/*max AMBA burst len = 0 (no sw limit*/
+		u32	reload_src:1;	/*auto reload src addr =1 if src is P*/
+		u32	reload_dst:1;	/*AR destn addr =1 if dstn is P*/
+	} cfgx;
+	u32	cfg_lo;
+};
+
+union intel_mid_dma_cfg_hi {
+	struct {
+		u32	fcmode:1;	/*flow control mode = 1*/
+		u32	fifo_mode:1;	/*FIFO mode select = 1*/
+		u32	protctl:3;	/*protection control = 0*/
+		u32	rsvd:2;
+		u32	src_per:4;	/*src hw HS interface*/
+		u32	dst_per:4;	/*dstn hw HS interface*/
+		u32	reser2:17;
+	} cfgx;
+	u32	cfg_hi;
+};
+
+/**
+ * struct intel_mid_dma_chan - internal mid representation of a DMA channel
+ * @chan: dma_chan strcture represetation for mid chan
+ * @ch_regs: MMIO register space pointer to channel register
+ * @dma_base: MMIO register space DMA engine base pointer
+ * @ch_id: DMA channel id
+ * @lock: channel spinlock
+ * @completed: DMA cookie
+ * @active_list: current active descriptors
+ * @queue: current queued up descriptors
+ * @free_list: current free descriptors
+ * @slave: dma slave struture
+ * @descs_allocated: total number of decsiptors allocated
+ * @dma: dma device struture pointer
+ * @in_use: bool representing if ch is in use or not
+ */
+struct intel_mid_dma_chan {
+	struct dma_chan		chan;
+	void __iomem		*ch_regs;
+	void __iomem		*dma_base;
+	int			ch_id;
+	spinlock_t		lock;
+	dma_cookie_t		completed;
+	struct list_head	active_list;
+	struct list_head	queue;
+	struct list_head	free_list;
+	struct intel_mid_dma_slave	*slave;
+	unsigned int		descs_allocated;
+	struct middma_device	*dma;
+	bool			in_use;
+};
+
+static inline struct intel_mid_dma_chan *to_intel_mid_dma_chan(
+						struct dma_chan *chan)
+{
+	return container_of(chan, struct intel_mid_dma_chan, chan);
+}
+
+/**
+ * struct middma_device - internal representation of a DMA device
+ * @pdev: PCI device
+ * @dma_base: MMIO register space pointer of DMA
+ * @dma_pool: for allocating DMA descriptors
+ * @common: embedded struct dma_device
+ * @tasklet: dma tasklet for processing interrupts
+ * @ch: per channel data
+ * @pci_id: DMA device PCI ID
+ * @intr_mask: Interrupt mask to be used
+ * @mask_reg: MMIO register for periphral mask
+ * @chan_base: Base ch index (read from driver data)
+ * @max_chan: max number of chs supported (from drv_data)
+ * @block_size: Block size of DMA transfer supported (from drv_data)
+ * @pimr_mask: MMIO register addr for periphral interrupt (from drv_data)
+ */
+struct middma_device {
+	struct pci_dev		*pdev;
+	void __iomem		*dma_base;
+	struct pci_pool		*dma_pool;
+	struct dma_device	common;
+	struct tasklet_struct   tasklet;
+	struct intel_mid_dma_chan ch[MAX_CHAN];
+	unsigned int		pci_id;
+	unsigned int		intr_mask;
+	void __iomem		*mask_reg;
+	int			chan_base;
+	int			max_chan;
+	int			block_size;
+	unsigned int		pimr_mask;
+};
+
+static inline struct middma_device *to_middma_device(struct dma_device *common)
+{
+	return container_of(common, struct middma_device, common);
+}
+
+struct intel_mid_dma_desc {
+	void __iomem			*block; /*ch ptr*/
+	struct list_head		desc_node;
+	struct dma_async_tx_descriptor	txd;
+	size_t				len;
+	dma_addr_t			sar;
+	dma_addr_t			dar;
+	u32				cfg_hi;
+	u32				cfg_lo;
+	u32				ctl_lo;
+	u32				ctl_hi;
+	dma_addr_t			next;
+	enum dma_data_direction		dirn;
+	enum dma_status			status;
+	enum intel_mid_dma_width	width; /*width of DMA txn*/
+	enum intel_mid_dma_mode		cfg_mode; /*mode configuration*/
+
+};
+
+static inline int test_ch_en(void __iomem *dma, u32 ch_no)
+{
+	u32 en_reg = ioread32(dma + DMA_CHAN_EN);
+	return (en_reg >> ch_no) & 0x1;
+}
+
+static inline struct intel_mid_dma_desc *to_intel_mid_dma_desc
+		(struct dma_async_tx_descriptor *txd)
+{
+	return container_of(txd, struct intel_mid_dma_desc, txd);
+}
+#endif /*__INTEL_MID_DMAC_REGS_H__*/

include/linux/intel_mid_dma.h

+/*
+ *  intel_mid_dma.h - Intel MID DMA Drivers
+ *
+ *  Copyright (C) 2008-10 Intel Corp
+ *  Author: Vinod Koul <vinod.koul@intel.com>
+ *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; version 2 of the License.
+ *
+ *  This program is distributed in the hope that it will be useful, but
+ *  WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ *
+ */
+#ifndef __INTEL_MID_DMA_H__
+#define __INTEL_MID_DMA_H__
+
+#include <linux/dmaengine.h>
+
+/*DMA transaction width, src and dstn width would be same
+The DMA length must be width aligned,
+for 32 bit width the length must be 32 bit (4bytes) aligned only*/
+enum intel_mid_dma_width {
+	LNW_DMA_WIDTH_8BIT = 0x0,
+	LNW_DMA_WIDTH_16BIT = 0x1,
+	LNW_DMA_WIDTH_32BIT = 0x2,
+};
+
+/*DMA mode configurations*/
+enum intel_mid_dma_mode {
+	LNW_DMA_PER_TO_MEM = 0, /*periphral to memory configuration*/
+	LNW_DMA_MEM_TO_PER,	/*memory to periphral configuration*/
+	LNW_DMA_MEM_TO_MEM,	/*mem to mem confg (testing only)*/
+};
+
+/*DMA handshaking*/
+enum intel_mid_dma_hs_mode {
+	LNW_DMA_HW_HS = 0,	/*HW Handshaking only*/
+	LNW_DMA_SW_HS = 1,	/*SW Handshaking not recommended*/
+};
+
+/*Burst size configuration*/
+enum intel_mid_dma_msize {
+	LNW_DMA_MSIZE_1 = 0x0,
+	LNW_DMA_MSIZE_4 = 0x1,
+	LNW_DMA_MSIZE_8 = 0x2,
+	LNW_DMA_MSIZE_16 = 0x3,
+	LNW_DMA_MSIZE_32 = 0x4,
+	LNW_DMA_MSIZE_64 = 0x5,
+};
+
+/**
+ * struct intel_mid_dma_slave - DMA slave structure
+ *
+ * @dirn: DMA trf direction
+ * @src_width: tx register width
+ * @dst_width: rx register width
+ * @hs_mode: HW/SW handshaking mode
+ * @cfg_mode: DMA data transfer mode (per-per/mem-per/mem-mem)
+ * @src_msize: Source DMA burst size
+ * @dst_msize: Dst DMA burst size
+ * @device_instance: DMA peripheral device instance, we can have multiple
+ *		peripheral device connected to single DMAC
+ */
+struct intel_mid_dma_slave {
+	enum dma_data_direction		dirn;
+	enum intel_mid_dma_width	src_width; /*width of DMA src txn*/
+	enum intel_mid_dma_width	dst_width; /*width of DMA dst txn*/
+	enum intel_mid_dma_hs_mode	hs_mode;  /*handshaking*/
+	enum intel_mid_dma_mode		cfg_mode; /*mode configuration*/
+	enum intel_mid_dma_msize	src_msize; /*size if src burst*/
+	enum intel_mid_dma_msize	dst_msize; /*size of dst burst*/
+	unsigned int		device_instance; /*0, 1 for periphral instance*/
+};
+
+#endif /*__INTEL_MID_DMA_H__*/