From 576e3c394a6c427c9a1378ec88ef7eb97e731992 Mon Sep 17 00:00:00 2001 From: Ramesh Babu K V Date: Mon, 4 Oct 2010 10:37:53 +0000 Subject: [PATCH] intel_mid_dma: Add sg list support to DMA driver For a very high speed DMA various periphral devices need scatter-gather list support. The DMA hardware support link list items. This list can be circular also (adding new flag DMA_PREP_CIRCULAR_LIST) Right now this flag is in driver header and should be moved to dmaengine header file eventually Signed-off-by: Ramesh Babu K V Signed-off-by: Vinod Koul Signed-off-by: Dan Williams --- drivers/dma/intel_mid_dma.c | 267 +++++++++++++++++++++++++------ drivers/dma/intel_mid_dma_regs.h | 30 +++- include/linux/intel_mid_dma.h | 3 + 3 files changed, 250 insertions(+), 50 deletions(-) diff --git a/drivers/dma/intel_mid_dma.c b/drivers/dma/intel_mid_dma.c index 3c4333ee1fb7..2ae1086b9481 100644 --- a/drivers/dma/intel_mid_dma.c +++ b/drivers/dma/intel_mid_dma.c @@ -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; } diff --git a/drivers/dma/intel_mid_dma_regs.h b/drivers/dma/intel_mid_dma_regs.h index a12dd2572dc3..7a5ac56d1324 100644 --- a/drivers/dma/intel_mid_dma_regs.h +++ b/drivers/dma/intel_mid_dma_regs.h @@ -29,11 +29,12 @@ #include #include -#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); diff --git a/include/linux/intel_mid_dma.h b/include/linux/intel_mid_dma.h index d9d08b6269b6..befe3fbd9e28 100644 --- a/include/linux/intel_mid_dma.h +++ b/include/linux/intel_mid_dma.h @@ -27,6 +27,7 @@ #include +#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*/ }; -- 2.20.1