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 <ramesh.b.k.v@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/dma/intel_mid_dma.c b/drivers/dma/intel_mid_dma.c
index 3c4333e..2ae1086 100644
--- a/drivers/dma/intel_mid_dma.c
+++ b/drivers/dma/intel_mid_dma.c
@@ -258,6 +258,7 @@
/*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 @@
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 @@
{
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 @@
/*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 @@
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 @@
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 @@
spin_unlock_bh(&midc->lock);
return 0;
}
- list_splice_init(&midc->free_list, &list);
+ /*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;
- /* Disable interrupts */
- disable_dma_interrupt(midc);
-
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 @@
/*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 @@
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 @@
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 @@
{
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 @@
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 @@
}
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 @@
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;
}