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Diffstat (limited to 'drivers/dma/coh901318.c')
-rw-r--r--drivers/dma/coh901318.c263
1 files changed, 191 insertions, 72 deletions
diff --git a/drivers/dma/coh901318.c b/drivers/dma/coh901318.c
index 1656fdc..a724e6b 100644
--- a/drivers/dma/coh901318.c
+++ b/drivers/dma/coh901318.c
@@ -37,7 +37,7 @@ struct coh901318_desc {
struct list_head node;
struct scatterlist *sg;
unsigned int sg_len;
- struct coh901318_lli *data;
+ struct coh901318_lli *lli;
enum dma_data_direction dir;
unsigned long flags;
};
@@ -283,7 +283,7 @@ static int coh901318_start(struct coh901318_chan *cohc)
}
static int coh901318_prep_linked_list(struct coh901318_chan *cohc,
- struct coh901318_lli *data)
+ struct coh901318_lli *lli)
{
int channel = cohc->id;
void __iomem *virtbase = cohc->base->virtbase;
@@ -292,18 +292,18 @@ static int coh901318_prep_linked_list(struct coh901318_chan *cohc,
COH901318_CX_STAT_SPACING*channel) &
COH901318_CX_STAT_ACTIVE);
- writel(data->src_addr,
+ writel(lli->src_addr,
virtbase + COH901318_CX_SRC_ADDR +
COH901318_CX_SRC_ADDR_SPACING * channel);
- writel(data->dst_addr, virtbase +
+ writel(lli->dst_addr, virtbase +
COH901318_CX_DST_ADDR +
COH901318_CX_DST_ADDR_SPACING * channel);
- writel(data->link_addr, virtbase + COH901318_CX_LNK_ADDR +
+ writel(lli->link_addr, virtbase + COH901318_CX_LNK_ADDR +
COH901318_CX_LNK_ADDR_SPACING * channel);
- writel(data->control, virtbase + COH901318_CX_CTRL +
+ writel(lli->control, virtbase + COH901318_CX_CTRL +
COH901318_CX_CTRL_SPACING * channel);
return 0;
@@ -408,33 +408,107 @@ coh901318_first_queued(struct coh901318_chan *cohc)
return d;
}
+static inline u32 coh901318_get_bytes_in_lli(struct coh901318_lli *in_lli)
+{
+ struct coh901318_lli *lli = in_lli;
+ u32 bytes = 0;
+
+ while (lli) {
+ bytes += lli->control & COH901318_CX_CTRL_TC_VALUE_MASK;
+ lli = lli->virt_link_addr;
+ }
+ return bytes;
+}
+
/*
- * DMA start/stop controls
+ * Get the number of bytes left to transfer on this channel,
+ * it is unwise to call this before stopping the channel for
+ * absolute measures, but for a rough guess you can still call
+ * it.
*/
-u32 coh901318_get_bytes_left(struct dma_chan *chan)
+static u32 coh901318_get_bytes_left(struct dma_chan *chan)
{
- unsigned long flags;
- u32 ret;
struct coh901318_chan *cohc = to_coh901318_chan(chan);
+ struct coh901318_desc *cohd;
+ struct list_head *pos;
+ unsigned long flags;
+ u32 left = 0;
+ int i = 0;
spin_lock_irqsave(&cohc->lock, flags);
- /* Read transfer count value */
- ret = readl(cohc->base->virtbase +
- COH901318_CX_CTRL+COH901318_CX_CTRL_SPACING *
- cohc->id) & COH901318_CX_CTRL_TC_VALUE_MASK;
+ /*
+ * If there are many queued jobs, we iterate and add the
+ * size of them all. We take a special look on the first
+ * job though, since it is probably active.
+ */
+ list_for_each(pos, &cohc->active) {
+ /*
+ * The first job in the list will be working on the
+ * hardware. The job can be stopped but still active,
+ * so that the transfer counter is somewhere inside
+ * the buffer.
+ */
+ cohd = list_entry(pos, struct coh901318_desc, node);
+
+ if (i == 0) {
+ struct coh901318_lli *lli;
+ dma_addr_t ladd;
+
+ /* Read current transfer count value */
+ left = readl(cohc->base->virtbase +
+ COH901318_CX_CTRL +
+ COH901318_CX_CTRL_SPACING * cohc->id) &
+ COH901318_CX_CTRL_TC_VALUE_MASK;
+
+ /* See if the transfer is linked... */
+ ladd = readl(cohc->base->virtbase +
+ COH901318_CX_LNK_ADDR +
+ COH901318_CX_LNK_ADDR_SPACING *
+ cohc->id) &
+ ~COH901318_CX_LNK_LINK_IMMEDIATE;
+ /* Single transaction */
+ if (!ladd)
+ continue;
+
+ /*
+ * Linked transaction, follow the lli, find the
+ * currently processing lli, and proceed to the next
+ */
+ lli = cohd->lli;
+ while (lli && lli->link_addr != ladd)
+ lli = lli->virt_link_addr;
+
+ if (lli)
+ lli = lli->virt_link_addr;
+
+ /*
+ * Follow remaining lli links around to count the total
+ * number of bytes left
+ */
+ left += coh901318_get_bytes_in_lli(lli);
+ } else {
+ left += coh901318_get_bytes_in_lli(cohd->lli);
+ }
+ i++;
+ }
+
+ /* Also count bytes in the queued jobs */
+ list_for_each(pos, &cohc->queue) {
+ cohd = list_entry(pos, struct coh901318_desc, node);
+ left += coh901318_get_bytes_in_lli(cohd->lli);
+ }
spin_unlock_irqrestore(&cohc->lock, flags);
- return ret;
+ return left;
}
-EXPORT_SYMBOL(coh901318_get_bytes_left);
-
-/* Stops a transfer without losing data. Enables power save.
- Use this function in conjunction with coh901318_continue(..)
-*/
-void coh901318_stop(struct dma_chan *chan)
+/*
+ * Pauses a transfer without losing data. Enables power save.
+ * Use this function in conjunction with coh901318_resume.
+ */
+static void coh901318_pause(struct dma_chan *chan)
{
u32 val;
unsigned long flags;
@@ -475,12 +549,11 @@ void coh901318_stop(struct dma_chan *chan)
spin_unlock_irqrestore(&cohc->lock, flags);
}
-EXPORT_SYMBOL(coh901318_stop);
-/* Continues a transfer that has been stopped via 300_dma_stop(..).
+/* Resumes a transfer that has been stopped via 300_dma_stop(..).
Power save is handled.
*/
-void coh901318_continue(struct dma_chan *chan)
+static void coh901318_resume(struct dma_chan *chan)
{
u32 val;
unsigned long flags;
@@ -506,7 +579,6 @@ void coh901318_continue(struct dma_chan *chan)
spin_unlock_irqrestore(&cohc->lock, flags);
}
-EXPORT_SYMBOL(coh901318_continue);
bool coh901318_filter_id(struct dma_chan *chan, void *chan_id)
{
@@ -565,29 +637,30 @@ static int coh901318_config(struct coh901318_chan *cohc,
*/
static struct coh901318_desc *coh901318_queue_start(struct coh901318_chan *cohc)
{
- struct coh901318_desc *cohd_que;
+ struct coh901318_desc *cohd;
- /* start queued jobs, if any
+ /*
+ * start queued jobs, if any
* TODO: transmit all queued jobs in one go
*/
- cohd_que = coh901318_first_queued(cohc);
+ cohd = coh901318_first_queued(cohc);
- if (cohd_que != NULL) {
+ if (cohd != NULL) {
/* Remove from queue */
- coh901318_desc_remove(cohd_que);
+ coh901318_desc_remove(cohd);
/* initiate DMA job */
cohc->busy = 1;
- coh901318_desc_submit(cohc, cohd_que);
+ coh901318_desc_submit(cohc, cohd);
- coh901318_prep_linked_list(cohc, cohd_que->data);
+ coh901318_prep_linked_list(cohc, cohd->lli);
- /* start dma job */
+ /* start dma job on this channel */
coh901318_start(cohc);
}
- return cohd_que;
+ return cohd;
}
/*
@@ -622,7 +695,7 @@ static void dma_tasklet(unsigned long data)
cohc->completed = cohd_fin->desc.cookie;
/* release the lli allocation and remove the descriptor */
- coh901318_lli_free(&cohc->base->pool, &cohd_fin->data);
+ coh901318_lli_free(&cohc->base->pool, &cohd_fin->lli);
/* return desc to free-list */
coh901318_desc_remove(cohd_fin);
@@ -666,23 +739,44 @@ static void dma_tasklet(unsigned long data)
/* called from interrupt context */
static void dma_tc_handle(struct coh901318_chan *cohc)
{
- BUG_ON(!cohc->allocated && (list_empty(&cohc->active) ||
- list_empty(&cohc->queue)));
-
- if (!cohc->allocated)
+ /*
+ * If the channel is not allocated, then we shouldn't have
+ * any TC interrupts on it.
+ */
+ if (!cohc->allocated) {
+ dev_err(COHC_2_DEV(cohc), "spurious interrupt from "
+ "unallocated channel\n");
return;
+ }
spin_lock(&cohc->lock);
+ /*
+ * When we reach this point, at least one queue item
+ * should have been moved over from cohc->queue to
+ * cohc->active and run to completion, that is why we're
+ * getting a terminal count interrupt is it not?
+ * If you get this BUG() the most probable cause is that
+ * the individual nodes in the lli chain have IRQ enabled,
+ * so check your platform config for lli chain ctrl.
+ */
+ BUG_ON(list_empty(&cohc->active));
+
cohc->nbr_active_done++;
+ /*
+ * This attempt to take a job from cohc->queue, put it
+ * into cohc->active and start it.
+ */
if (coh901318_queue_start(cohc) == NULL)
cohc->busy = 0;
- BUG_ON(list_empty(&cohc->active));
-
spin_unlock(&cohc->lock);
+ /*
+ * This tasklet will remove items from cohc->active
+ * and thus terminates them.
+ */
if (cohc_chan_conf(cohc)->priority_high)
tasklet_hi_schedule(&cohc->tasklet);
else
@@ -809,6 +903,7 @@ static irqreturn_t dma_irq_handler(int irq, void *dev_id)
static int coh901318_alloc_chan_resources(struct dma_chan *chan)
{
struct coh901318_chan *cohc = to_coh901318_chan(chan);
+ unsigned long flags;
dev_vdbg(COHC_2_DEV(cohc), "[%s] DMA channel %d\n",
__func__, cohc->id);
@@ -816,11 +911,15 @@ static int coh901318_alloc_chan_resources(struct dma_chan *chan)
if (chan->client_count > 1)
return -EBUSY;
+ spin_lock_irqsave(&cohc->lock, flags);
+
coh901318_config(cohc, NULL);
cohc->allocated = 1;
cohc->completed = chan->cookie = 1;
+ spin_unlock_irqrestore(&cohc->lock, flags);
+
return 1;
}
@@ -843,7 +942,7 @@ coh901318_free_chan_resources(struct dma_chan *chan)
spin_unlock_irqrestore(&cohc->lock, flags);
- chan->device->device_terminate_all(chan);
+ chan->device->device_control(chan, DMA_TERMINATE_ALL, 0);
}
@@ -870,7 +969,7 @@ static struct dma_async_tx_descriptor *
coh901318_prep_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
size_t size, unsigned long flags)
{
- struct coh901318_lli *data;
+ struct coh901318_lli *lli;
struct coh901318_desc *cohd;
unsigned long flg;
struct coh901318_chan *cohc = to_coh901318_chan(chan);
@@ -892,23 +991,23 @@ coh901318_prep_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
if ((lli_len << MAX_DMA_PACKET_SIZE_SHIFT) < size)
lli_len++;
- data = coh901318_lli_alloc(&cohc->base->pool, lli_len);
+ lli = coh901318_lli_alloc(&cohc->base->pool, lli_len);
- if (data == NULL)
+ if (lli == NULL)
goto err;
ret = coh901318_lli_fill_memcpy(
- &cohc->base->pool, data, src, size, dest,
+ &cohc->base->pool, lli, src, size, dest,
cohc_chan_param(cohc)->ctrl_lli_chained,
ctrl_last);
if (ret)
goto err;
- COH_DBG(coh901318_list_print(cohc, data));
+ COH_DBG(coh901318_list_print(cohc, lli));
/* Pick a descriptor to handle this transfer */
cohd = coh901318_desc_get(cohc);
- cohd->data = data;
+ cohd->lli = lli;
cohd->flags = flags;
cohd->desc.tx_submit = coh901318_tx_submit;
@@ -926,7 +1025,7 @@ coh901318_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
unsigned long flags)
{
struct coh901318_chan *cohc = to_coh901318_chan(chan);
- struct coh901318_lli *data;
+ struct coh901318_lli *lli;
struct coh901318_desc *cohd;
const struct coh901318_params *params;
struct scatterlist *sg;
@@ -999,13 +1098,13 @@ coh901318_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
}
pr_debug("Allocate %d lli:s for this transfer\n", len);
- data = coh901318_lli_alloc(&cohc->base->pool, len);
+ lli = coh901318_lli_alloc(&cohc->base->pool, len);
- if (data == NULL)
+ if (lli == NULL)
goto err_dma_alloc;
- /* initiate allocated data list */
- ret = coh901318_lli_fill_sg(&cohc->base->pool, data, sgl, sg_len,
+ /* initiate allocated lli list */
+ ret = coh901318_lli_fill_sg(&cohc->base->pool, lli, sgl, sg_len,
cohc_dev_addr(cohc),
ctrl_chained,
ctrl,
@@ -1014,14 +1113,14 @@ coh901318_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
if (ret)
goto err_lli_fill;
- COH_DBG(coh901318_list_print(cohc, data));
+ COH_DBG(coh901318_list_print(cohc, lli));
/* Pick a descriptor to handle this transfer */
cohd = coh901318_desc_get(cohc);
cohd->dir = direction;
cohd->flags = flags;
cohd->desc.tx_submit = coh901318_tx_submit;
- cohd->data = data;
+ cohd->lli = lli;
spin_unlock_irqrestore(&cohc->lock, flg);
@@ -1035,9 +1134,8 @@ coh901318_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
}
static enum dma_status
-coh901318_is_tx_complete(struct dma_chan *chan,
- dma_cookie_t cookie, dma_cookie_t *done,
- dma_cookie_t *used)
+coh901318_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
+ struct dma_tx_state *txstate)
{
struct coh901318_chan *cohc = to_coh901318_chan(chan);
dma_cookie_t last_used;
@@ -1049,10 +1147,10 @@ coh901318_is_tx_complete(struct dma_chan *chan,
ret = dma_async_is_complete(cookie, last_complete, last_used);
- if (done)
- *done = last_complete;
- if (used)
- *used = last_used;
+ dma_set_tx_state(txstate, last_complete, last_used,
+ coh901318_get_bytes_left(chan));
+ if (ret == DMA_IN_PROGRESS && cohc->stopped)
+ ret = DMA_PAUSED;
return ret;
}
@@ -1065,23 +1163,42 @@ coh901318_issue_pending(struct dma_chan *chan)
spin_lock_irqsave(&cohc->lock, flags);
- /* Busy means that pending jobs are already being processed */
+ /*
+ * Busy means that pending jobs are already being processed,
+ * and then there is no point in starting the queue: the
+ * terminal count interrupt on the channel will take the next
+ * job on the queue and execute it anyway.
+ */
if (!cohc->busy)
coh901318_queue_start(cohc);
spin_unlock_irqrestore(&cohc->lock, flags);
}
-static void
-coh901318_terminate_all(struct dma_chan *chan)
+static int
+coh901318_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
+ unsigned long arg)
{
unsigned long flags;
struct coh901318_chan *cohc = to_coh901318_chan(chan);
struct coh901318_desc *cohd;
void __iomem *virtbase = cohc->base->virtbase;
- coh901318_stop(chan);
+ if (cmd == DMA_PAUSE) {
+ coh901318_pause(chan);
+ return 0;
+ }
+
+ if (cmd == DMA_RESUME) {
+ coh901318_resume(chan);
+ return 0;
+ }
+ if (cmd != DMA_TERMINATE_ALL)
+ return -ENXIO;
+
+ /* The remainder of this function terminates the transfer */
+ coh901318_pause(chan);
spin_lock_irqsave(&cohc->lock, flags);
/* Clear any pending BE or TC interrupt */
@@ -1099,7 +1216,7 @@ coh901318_terminate_all(struct dma_chan *chan)
while ((cohd = coh901318_first_active_get(cohc))) {
/* release the lli allocation*/
- coh901318_lli_free(&cohc->base->pool, &cohd->data);
+ coh901318_lli_free(&cohc->base->pool, &cohd->lli);
/* return desc to free-list */
coh901318_desc_remove(cohd);
@@ -1108,7 +1225,7 @@ coh901318_terminate_all(struct dma_chan *chan)
while ((cohd = coh901318_first_queued(cohc))) {
/* release the lli allocation*/
- coh901318_lli_free(&cohc->base->pool, &cohd->data);
+ coh901318_lli_free(&cohc->base->pool, &cohd->lli);
/* return desc to free-list */
coh901318_desc_remove(cohd);
@@ -1120,6 +1237,8 @@ coh901318_terminate_all(struct dma_chan *chan)
cohc->busy = 0;
spin_unlock_irqrestore(&cohc->lock, flags);
+
+ return 0;
}
void coh901318_base_init(struct dma_device *dma, const int *pick_chans,
struct coh901318_base *base)
@@ -1235,9 +1354,9 @@ static int __init coh901318_probe(struct platform_device *pdev)
base->dma_slave.device_alloc_chan_resources = coh901318_alloc_chan_resources;
base->dma_slave.device_free_chan_resources = coh901318_free_chan_resources;
base->dma_slave.device_prep_slave_sg = coh901318_prep_slave_sg;
- base->dma_slave.device_is_tx_complete = coh901318_is_tx_complete;
+ base->dma_slave.device_tx_status = coh901318_tx_status;
base->dma_slave.device_issue_pending = coh901318_issue_pending;
- base->dma_slave.device_terminate_all = coh901318_terminate_all;
+ base->dma_slave.device_control = coh901318_control;
base->dma_slave.dev = &pdev->dev;
err = dma_async_device_register(&base->dma_slave);
@@ -1255,9 +1374,9 @@ static int __init coh901318_probe(struct platform_device *pdev)
base->dma_memcpy.device_alloc_chan_resources = coh901318_alloc_chan_resources;
base->dma_memcpy.device_free_chan_resources = coh901318_free_chan_resources;
base->dma_memcpy.device_prep_dma_memcpy = coh901318_prep_memcpy;
- base->dma_memcpy.device_is_tx_complete = coh901318_is_tx_complete;
+ base->dma_memcpy.device_tx_status = coh901318_tx_status;
base->dma_memcpy.device_issue_pending = coh901318_issue_pending;
- base->dma_memcpy.device_terminate_all = coh901318_terminate_all;
+ base->dma_memcpy.device_control = coh901318_control;
base->dma_memcpy.dev = &pdev->dev;
/*
* This controller can only access address at even 32bit boundaries,
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