intel_mid_dma: Add sg list support to DMA driver (576e3c39) · Commits · 戴 / test

drivers/dma/intel_mid_dma.c

+221 −46

Original line number	Diff line number	Diff line
		@@ -258,6 +258,7 @@ static void midc_dostart(struct intel_mid_dma_chan *midc,
		/write registers and en/
		iowrite32(first->sar, midc->ch_regs + SAR);
		iowrite32(first->dar, midc->ch_regs + DAR);
		iowrite32(first->lli_phys, midc->ch_regs + LLP);
		iowrite32(first->cfg_hi, midc->ch_regs + CFG_HIGH);
		iowrite32(first->cfg_lo, midc->ch_regs + CFG_LOW);
		iowrite32(first->ctl_lo, midc->ch_regs + CTL_LOW);
		@@ -265,9 +266,9 @@ static void midc_dostart(struct intel_mid_dma_chan *midc,
		pr_debug("MDMA:TX SAR %x,DAR %x,CFGL %x,CFGH %x,CTLH %x, CTLL %x\n",
		(int)first->sar, (int)first->dar, first->cfg_hi,
		first->cfg_lo, first->ctl_hi, first->ctl_lo);
		first->status = DMA_IN_PROGRESS;

		iowrite32(ENABLE_CHANNEL(midc->ch_id), mid->dma_base + DMA_CHAN_EN);
		first->status = DMA_IN_PROGRESS;
		}

		/**
		@@ -284,20 +285,36 @@ static void midc_descriptor_complete(struct intel_mid_dma_chan *midc,
		{
		struct dma_async_tx_descriptor *txd = &desc->txd;
		dma_async_tx_callback callback_txd = NULL;
		struct intel_mid_dma_lli *llitem;
		void *param_txd = NULL;

		midc->completed = txd->cookie;
		callback_txd = txd->callback;
		param_txd = txd->callback_param;

		list_move(&desc->desc_node, &midc->free_list);
		midc->busy = false;
		if (desc->lli != NULL) {
		/clear the DONE bit of completed LLI in memory/
		llitem = desc->lli + desc->current_lli;
		llitem->ctl_hi &= CLEAR_DONE;
		if (desc->current_lli < desc->lli_length-1)
		(desc->current_lli)++;
		else
		desc->current_lli = 0;
		}
		spin_unlock_bh(&midc->lock);
		if (callback_txd) {
		pr_debug("MDMA: TXD callback set ... calling\n");
		callback_txd(param_txd);
		spin_lock_bh(&midc->lock);
		return;
		}
		if (midc->raw_tfr) {
		desc->status = DMA_SUCCESS;
		if (desc->lli != NULL) {
		pci_pool_free(desc->lli_pool, desc->lli,
		desc->lli_phys);
		pci_pool_destroy(desc->lli_pool);
		}
		list_move(&desc->desc_node, &midc->free_list);
		midc->busy = false;
		}
		spin_lock_bh(&midc->lock);

		@@ -318,14 +335,89 @@ static void midc_scan_descriptors(struct middma_device *mid,

		/tx is complete/
		list_for_each_entry_safe(desc, _desc, &midc->active_list, desc_node) {
		if (desc->status == DMA_IN_PROGRESS) {
		desc->status = DMA_SUCCESS;
		if (desc->status == DMA_IN_PROGRESS)
		midc_descriptor_complete(midc, desc);
		}
		}
		return;
		}
		/**
		* midc_lli_fill_sg - Helper function to convert
		* SG list to Linked List Items.
		*@midc: Channel
		*@desc: DMA descriptor
		*@sglist: Pointer to SG list
		*@sglen: SG list length
		*@flags: DMA transaction flags
		*
		* Walk through the SG list and convert the SG list into Linked
		* List Items (LLI).
		*/
		static int midc_lli_fill_sg(struct intel_mid_dma_chan *midc,
		struct intel_mid_dma_desc *desc,
		struct scatterlist *sglist,
		unsigned int sglen,
		unsigned int flags)
		{
		struct intel_mid_dma_slave *mids;
		struct scatterlist *sg;
		dma_addr_t lli_next, sg_phy_addr;
		struct intel_mid_dma_lli *lli_bloc_desc;
		union intel_mid_dma_ctl_lo ctl_lo;
		union intel_mid_dma_ctl_hi ctl_hi;
		int i;

		pr_debug("MDMA: Entered midc_lli_fill_sg\n");
		mids = midc->chan.private;

		lli_bloc_desc = desc->lli;
		lli_next = desc->lli_phys;

		ctl_lo.ctl_lo = desc->ctl_lo;
		ctl_hi.ctl_hi = desc->ctl_hi;
		for_each_sg(sglist, sg, sglen, i) {
		/Populate CTL_LOW and LLI values/
		if (i != sglen - 1) {
		lli_next = lli_next +
		sizeof(struct intel_mid_dma_lli);
		} else {
		/Check for circular list, otherwise terminate LLI to ZERO/
		if (flags & DMA_PREP_CIRCULAR_LIST) {
		pr_debug("MDMA: LLI is configured in circular mode\n");
		lli_next = desc->lli_phys;
		} else {
		lli_next = 0;
		ctl_lo.ctlx.llp_dst_en = 0;
		ctl_lo.ctlx.llp_src_en = 0;
		}
		}
		/Populate CTL_HI values/
		ctl_hi.ctlx.block_ts = get_block_ts(sg->length,
		desc->width,
		midc->dma->block_size);
		/Populate SAR and DAR values/
		sg_phy_addr = sg_phys(sg);
		if (desc->dirn == DMA_TO_DEVICE) {
		lli_bloc_desc->sar = sg_phy_addr;
		lli_bloc_desc->dar = mids->per_addr;
		} else if (desc->dirn == DMA_FROM_DEVICE) {
		lli_bloc_desc->sar = mids->per_addr;
		lli_bloc_desc->dar = sg_phy_addr;
		}
		/Copy values into block descriptor in system memroy/
		lli_bloc_desc->llp = lli_next;
		lli_bloc_desc->ctl_lo = ctl_lo.ctl_lo;
		lli_bloc_desc->ctl_hi = ctl_hi.ctl_hi;

		lli_bloc_desc++;
		}
		/Copy very first LLI values to descriptor/
		desc->ctl_lo = desc->lli->ctl_lo;
		desc->ctl_hi = desc->lli->ctl_hi;
		desc->sar = desc->lli->sar;
		desc->dar = desc->lli->dar;

		return 0;
		}
		/*****************************************************************************
		DMA engine callback Functions*/
		/**
		@@ -350,12 +442,12 @@ static dma_cookie_t intel_mid_dma_tx_submit(struct dma_async_tx_descriptor *tx)
		desc->txd.cookie = cookie;


		if (list_empty(&midc->active_list)) {
		midc_dostart(midc, desc);
		if (list_empty(&midc->active_list))
		list_add_tail(&desc->desc_node, &midc->active_list);
		} else {
		else
		list_add_tail(&desc->desc_node, &midc->queue);
		}

		midc_dostart(midc, desc);
		spin_unlock_bh(&midc->lock);

		return cookie;
		@@ -429,7 +521,7 @@ static int intel_mid_dma_device_control(struct dma_chan *chan,
		struct intel_mid_dma_chan *midc = to_intel_mid_dma_chan(chan);
		struct middma_device *mid = to_middma_device(chan->device);
		struct intel_mid_dma_desc desc, _desc;
		LIST_HEAD(list);
		union intel_mid_dma_cfg_lo cfg_lo;

		if (cmd != DMA_TERMINATE_ALL)
		return -ENXIO;
		@@ -439,39 +531,29 @@ static int intel_mid_dma_device_control(struct dma_chan *chan,
		spin_unlock_bh(&midc->lock);
		return 0;
		}
		list_splice_init(&midc->free_list, &list);
		midc->descs_allocated = 0;
		midc->slave = NULL;

		/Suspend and disable the channel/
		cfg_lo.cfg_lo = ioread32(midc->ch_regs + CFG_LOW);
		cfg_lo.cfgx.ch_susp = 1;
		iowrite32(cfg_lo.cfg_lo, midc->ch_regs + CFG_LOW);
		iowrite32(DISABLE_CHANNEL(midc->ch_id), mid->dma_base + DMA_CHAN_EN);
		midc->busy = false;
		/* Disable interrupts */
		disable_dma_interrupt(midc);
		midc->descs_allocated = 0;
		midc->slave = NULL;

		spin_unlock_bh(&midc->lock);
		list_for_each_entry_safe(desc, _desc, &list, desc_node) {
		pr_debug("MDMA: freeing descriptor %p\n", desc);
		pci_pool_free(mid->dma_pool, desc, desc->txd.phys);
		list_for_each_entry_safe(desc, _desc, &midc->active_list, desc_node) {
		if (desc->lli != NULL) {
		pci_pool_free(desc->lli_pool, desc->lli,
		desc->lli_phys);
		pci_pool_destroy(desc->lli_pool);
		}
		list_move(&desc->desc_node, &midc->free_list);
		}
		return 0;
		}

		/**
		* intel_mid_dma_prep_slave_sg - Prep slave sg txn
		* @chan: chan for DMA transfer
		* @sgl: scatter gather list
		* @sg_len: length of sg txn
		* @direction: DMA transfer dirtn
		* @flags: DMA flags
		*
		* Do DMA sg txn: NOT supported now
		*/
		static struct dma_async_tx_descriptor *intel_mid_dma_prep_slave_sg(
		struct dma_chan chan, struct scatterlist sgl,
		unsigned int sg_len, enum dma_data_direction direction,
		unsigned long flags)
		{
		/not supported now/
		return NULL;
		}

		/**
		* intel_mid_dma_prep_memcpy - Prep memcpy txn
		@@ -553,6 +635,7 @@ static struct dma_async_tx_descriptor *intel_mid_dma_prep_memcpy(

		/calculate CTL_HI/
		ctl_hi.ctlx.reser = 0;
		ctl_hi.ctlx.done = 0;
		width = mids->src_width;

		ctl_hi.ctlx.block_ts = get_block_ts(len, width, midc->dma->block_size);
		@@ -599,6 +682,9 @@ static struct dma_async_tx_descriptor *intel_mid_dma_prep_memcpy(
		desc->ctl_hi = ctl_hi.ctl_hi;
		desc->width = width;
		desc->dirn = mids->dirn;
		desc->lli_phys = 0;
		desc->lli = NULL;
		desc->lli_pool = NULL;
		return &desc->txd;

		err_desc_get:
		@@ -606,6 +692,85 @@ err_desc_get:
		midc_desc_put(midc, desc);
		return NULL;
		}
		/**
		* intel_mid_dma_prep_slave_sg - Prep slave sg txn
		* @chan: chan for DMA transfer
		* @sgl: scatter gather list
		* @sg_len: length of sg txn
		* @direction: DMA transfer dirtn
		* @flags: DMA flags
		*
		* Prepares LLI based periphral transfer
		*/
		static struct dma_async_tx_descriptor *intel_mid_dma_prep_slave_sg(
		struct dma_chan chan, struct scatterlist sgl,
		unsigned int sg_len, enum dma_data_direction direction,
		unsigned long flags)
		{
		struct intel_mid_dma_chan *midc = NULL;
		struct intel_mid_dma_slave *mids = NULL;
		struct intel_mid_dma_desc *desc = NULL;
		struct dma_async_tx_descriptor *txd = NULL;
		union intel_mid_dma_ctl_lo ctl_lo;

		pr_debug("MDMA: Prep for slave SG\n");

		if (!sg_len) {
		pr_err("MDMA: Invalid SG length\n");
		return NULL;
		}
		midc = to_intel_mid_dma_chan(chan);
		BUG_ON(!midc);

		mids = chan->private;
		BUG_ON(!mids);

		if (!midc->dma->pimr_mask) {
		pr_debug("MDMA: SG list is not supported by this controller\n");
		return NULL;
		}

		pr_debug("MDMA: SG Length = %d, direction = %d, Flags = %#lx\n",
		sg_len, direction, flags);

		txd = intel_mid_dma_prep_memcpy(chan, 0, 0, sgl->length, flags);
		if (NULL == txd) {
		pr_err("MDMA: Prep memcpy failed\n");
		return NULL;
		}
		desc = to_intel_mid_dma_desc(txd);
		desc->dirn = direction;
		ctl_lo.ctl_lo = desc->ctl_lo;
		ctl_lo.ctlx.llp_dst_en = 1;
		ctl_lo.ctlx.llp_src_en = 1;
		desc->ctl_lo = ctl_lo.ctl_lo;
		desc->lli_length = sg_len;
		desc->current_lli = 0;
		/* DMA coherent memory pool for LLI descriptors*/
		desc->lli_pool = pci_pool_create("intel_mid_dma_lli_pool",
		midc->dma->pdev,
		(sizeof(struct intel_mid_dma_lli)*sg_len),
		32, 0);
		if (NULL == desc->lli_pool) {
		pr_err("MID_DMA:LLI pool create failed\n");
		return NULL;
		}

		desc->lli = pci_pool_alloc(desc->lli_pool, GFP_KERNEL, &desc->lli_phys);
		if (!desc->lli) {
		pr_err("MID_DMA: LLI alloc failed\n");
		pci_pool_destroy(desc->lli_pool);
		return NULL;
		}

		midc_lli_fill_sg(midc, desc, sgl, sg_len, flags);
		if (flags & DMA_PREP_INTERRUPT) {
		iowrite32(UNMASK_INTR_REG(midc->ch_id),
		midc->dma_base + MASK_BLOCK);
		pr_debug("MDMA:Enabled Block interrupt\n");
		}
		return &desc->txd;
		}

		/**
		* intel_mid_dma_free_chan_resources - Frees dma resources
		@@ -728,7 +893,7 @@ static void dma_tasklet(unsigned long data)
		{
		struct middma_device *mid = NULL;
		struct intel_mid_dma_chan *midc = NULL;
		u32 status;
		u32 status, raw_tfr, raw_block;
		int i;

		mid = (struct middma_device *)data;
		@@ -737,8 +902,9 @@ static void dma_tasklet(unsigned long data)
		return;
		}
		pr_debug("MDMA: in tasklet for device %x\n", mid->pci_id);
		status = ioread32(mid->dma_base + RAW_TFR);
		pr_debug("MDMA:RAW_TFR %x\n", status);
		raw_tfr = ioread32(mid->dma_base + RAW_TFR);
		raw_block = ioread32(mid->dma_base + RAW_BLOCK);
		status = raw_tfr \| raw_block;
		status &= mid->intr_mask;
		while (status) {
		/txn interrupt/
		@@ -754,15 +920,23 @@ static void dma_tasklet(unsigned long data)
		}
		pr_debug("MDMA:Tx complete interrupt %x, Ch No %d Index %d\n",
		status, midc->ch_id, i);
		midc->raw_tfr = raw_tfr;
		midc->raw_block = raw_block;
		spin_lock_bh(&midc->lock);
		/clearing this interrupts first/
		iowrite32((1 << midc->ch_id), mid->dma_base + CLEAR_TFR);
		iowrite32((1 << midc->ch_id), mid->dma_base + CLEAR_BLOCK);

		spin_lock_bh(&midc->lock);
		if (raw_block) {
		iowrite32((1 << midc->ch_id),
		mid->dma_base + CLEAR_BLOCK);
		}
		midc_scan_descriptors(mid, midc);
		pr_debug("MDMA:Scan of desc... complete, unmasking\n");
		iowrite32(UNMASK_INTR_REG(midc->ch_id),
		mid->dma_base + MASK_TFR);
		if (raw_block) {
		iowrite32(UNMASK_INTR_REG(midc->ch_id),
		mid->dma_base + MASK_BLOCK);
		}
		spin_unlock_bh(&midc->lock);
		}

		@@ -836,7 +1010,8 @@ static irqreturn_t intel_mid_dma_interrupt(int irq, void *data)
		tfr_status &= mid->intr_mask;
		if (tfr_status) {
		/need to disable intr/
		iowrite32((tfr_status << 8), mid->dma_base + MASK_TFR);
		iowrite32((tfr_status << INT_MASK_WE), mid->dma_base + MASK_TFR);
		iowrite32((tfr_status << INT_MASK_WE), mid->dma_base + MASK_BLOCK);
		pr_debug("MDMA: Calling tasklet %x\n", tfr_status);
		call_tasklet = 1;
		}

drivers/dma/intel_mid_dma_regs.h

+26 −4

Original line number	Diff line number	Diff line
		@@ -29,11 +29,12 @@
		#include <linux/dmapool.h>
		#include <linux/pci_ids.h>

		#define INTEL_MID_DMA_DRIVER_VERSION "1.0.6"
		#define INTEL_MID_DMA_DRIVER_VERSION "1.1.0"

		#define REG_BIT0 0x00000001
		#define REG_BIT8 0x00000100

		#define INT_MASK_WE 0x8
		#define CLEAR_DONE 0xFFFFEFFF
		#define UNMASK_INTR_REG(chan_num) \
		((REG_BIT0 << chan_num) \| (REG_BIT8 << chan_num))
		#define MASK_INTR_REG(chan_num) (REG_BIT8 << chan_num)
		@@ -41,6 +42,9 @@
		#define ENABLE_CHANNEL(chan_num) \
		((REG_BIT0 << chan_num) \| (REG_BIT8 << chan_num))

		#define DISABLE_CHANNEL(chan_num) \
		(REG_BIT8 << chan_num)

		#define DESCS_PER_CHANNEL 16
		/DMA Registers/
		/registers associated with channel programming/
		@@ -50,6 +54,7 @@
		/CH X REG = (DMA_CH_SIZE)CH_NO + REG*/
		#define SAR 0x00 /* Source Address Register*/
		#define DAR 0x08 /* Destination Address Register*/
		#define LLP 0x10 /* Linked List Pointer Register*/
		#define CTL_LOW 0x18 /* Control Register*/
		#define CTL_HIGH 0x1C /* Control Register*/
		#define CFG_LOW 0x40 /* Configuration Register Low*/
		@@ -112,8 +117,8 @@ union intel_mid_dma_ctl_lo {
		union intel_mid_dma_ctl_hi {
		struct {
		u32 block_ts:12; /block transfer size/
		/configured by DMAC/
		u32 reser:20;
		u32 done:1; /Done - updated by DMAC/
		u32 reser:19; /configured by DMAC/
		} ctlx;
		u32 ctl_hi;

		@@ -169,6 +174,8 @@ union intel_mid_dma_cfg_hi {
		* @dma: dma device struture pointer
		* @busy: bool representing if ch is busy (active txn) or not
		* @in_use: bool representing if ch is in use or not
		* @raw_tfr: raw trf interrupt recieved
		* @raw_block: raw block interrupt recieved
		*/
		struct intel_mid_dma_chan {
		struct dma_chan chan;
		@@ -185,6 +192,8 @@ struct intel_mid_dma_chan {
		struct middma_device *dma;
		bool busy;
		bool in_use;
		u32 raw_tfr;
		u32 raw_block;
		};

		static inline struct intel_mid_dma_chan *to_intel_mid_dma_chan(
		@@ -247,6 +256,11 @@ struct intel_mid_dma_desc {
		u32 cfg_lo;
		u32 ctl_lo;
		u32 ctl_hi;
		struct pci_pool *lli_pool;
		struct intel_mid_dma_lli *lli;
		dma_addr_t lli_phys;
		unsigned int lli_length;
		unsigned int current_lli;
		dma_addr_t next;
		enum dma_data_direction dirn;
		enum dma_status status;
		@@ -255,6 +269,14 @@ struct intel_mid_dma_desc {

		};

		struct intel_mid_dma_lli {
		dma_addr_t sar;
		dma_addr_t dar;
		dma_addr_t llp;
		u32 ctl_lo;
		u32 ctl_hi;
		} __attribute__ ((packed));

		static inline int test_ch_en(void __iomem *dma, u32 ch_no)
		{
		u32 en_reg = ioread32(dma + DMA_CHAN_EN);

include/linux/intel_mid_dma.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -27,6 +27,7 @@

		#include <linux/dmaengine.h>

		#define DMA_PREP_CIRCULAR_LIST (1 << 10)
		/*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*/
		@@ -69,6 +70,7 @@ enum intel_mid_dma_msize {
		* @cfg_mode: DMA data transfer mode (per-per/mem-per/mem-mem)
		* @src_msize: Source DMA burst size
		* @dst_msize: Dst DMA burst size
		* @per_addr: Periphral address
		* @device_instance: DMA peripheral device instance, we can have multiple
		* peripheral device connected to single DMAC
		*/
		@@ -80,6 +82,7 @@ struct intel_mid_dma_slave {
		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/
		dma_addr_t per_addr; /Peripheral address/
		unsigned int device_instance; /0, 1 for periphral instance/
		};

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