summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
Diffstat
-rw-r--r--arch/arm/mach-tegra/dma.c197
1 files changed, 108 insertions, 89 deletions
diff --git a/arch/arm/mach-tegra/dma.c b/arch/arm/mach-tegra/dma.c
index a2a252db024..250bc7baa00 100644
--- a/arch/arm/mach-tegra/dma.c
+++ b/arch/arm/mach-tegra/dma.c
@@ -121,17 +121,13 @@ struct tegra_dma_channel {
void __iomem *addr;
int mode;
int irq;
-
- /* Register shadow */
- u32 csr;
- u32 ahb_seq;
- u32 ahb_ptr;
- u32 apb_seq;
- u32 apb_ptr;
+ int req_transfer_count;
};
#define NV_DMA_MAX_CHANNELS 32
+static DEFINE_MUTEX(tegra_dma_lock);
+
static DECLARE_BITMAP(channel_usage, NV_DMA_MAX_CHANNELS);
static struct tegra_dma_channel dma_channels[NV_DMA_MAX_CHANNELS];
@@ -139,7 +135,6 @@ static void tegra_dma_update_hw(struct tegra_dma_channel *ch,
struct tegra_dma_req *req);
static void tegra_dma_update_hw_partial(struct tegra_dma_channel *ch,
struct tegra_dma_req *req);
-static void tegra_dma_init_hw(struct tegra_dma_channel *ch);
static void tegra_dma_stop(struct tegra_dma_channel *ch);
void tegra_dma_flush(struct tegra_dma_channel *ch)
@@ -151,6 +146,9 @@ void tegra_dma_dequeue(struct tegra_dma_channel *ch)
{
struct tegra_dma_req *req;
+ if (tegra_dma_is_empty(ch))
+ return;
+
req = list_entry(ch->list.next, typeof(*req), node);
tegra_dma_dequeue_req(ch, req);
@@ -159,10 +157,10 @@ void tegra_dma_dequeue(struct tegra_dma_channel *ch)
void tegra_dma_stop(struct tegra_dma_channel *ch)
{
- unsigned int csr;
- unsigned int status;
+ u32 csr;
+ u32 status;
- csr = ch->csr;
+ csr = readl(ch->addr + APB_DMA_CHAN_CSR);
csr &= ~CSR_IE_EOC;
writel(csr, ch->addr + APB_DMA_CHAN_CSR);
@@ -176,19 +174,16 @@ void tegra_dma_stop(struct tegra_dma_channel *ch)
int tegra_dma_cancel(struct tegra_dma_channel *ch)
{
- unsigned int csr;
+ u32 csr;
unsigned long irq_flags;
spin_lock_irqsave(&ch->lock, irq_flags);
while (!list_empty(&ch->list))
list_del(ch->list.next);
- csr = ch->csr;
+ csr = readl(ch->addr + APB_DMA_CHAN_CSR);
csr &= ~CSR_REQ_SEL_MASK;
csr |= CSR_REQ_SEL_INVALID;
-
- /* Set the enable as that is not shadowed */
- csr |= CSR_ENB;
writel(csr, ch->addr + APB_DMA_CHAN_CSR);
tegra_dma_stop(ch);
@@ -230,18 +225,15 @@ int tegra_dma_dequeue_req(struct tegra_dma_channel *ch,
* - Finally stop or program the DMA to the next buffer in the
* list.
*/
- csr = ch->csr;
+ csr = readl(ch->addr + APB_DMA_CHAN_CSR);
csr &= ~CSR_REQ_SEL_MASK;
csr |= CSR_REQ_SEL_INVALID;
-
- /* Set the enable as that is not shadowed */
- csr |= CSR_ENB;
writel(csr, ch->addr + APB_DMA_CHAN_CSR);
/* Get the transfer count */
status = readl(ch->addr + APB_DMA_CHAN_STA);
to_transfer = (status & STA_COUNT_MASK) >> STA_COUNT_SHIFT;
- req_transfer_count = (ch->csr & CSR_WCOUNT_MASK) >> CSR_WCOUNT_SHIFT;
+ req_transfer_count = ch->req_transfer_count;
req_transfer_count += 1;
to_transfer += 1;
@@ -349,7 +341,9 @@ EXPORT_SYMBOL(tegra_dma_enqueue_req);
struct tegra_dma_channel *tegra_dma_allocate_channel(int mode)
{
int channel;
- struct tegra_dma_channel *ch;
+ struct tegra_dma_channel *ch = NULL;
+
+ mutex_lock(&tegra_dma_lock);
/* first channel is the shared channel */
if (mode & TEGRA_DMA_SHARED) {
@@ -358,11 +352,14 @@ struct tegra_dma_channel *tegra_dma_allocate_channel(int mode)
channel = find_first_zero_bit(channel_usage,
ARRAY_SIZE(dma_channels));
if (channel >= ARRAY_SIZE(dma_channels))
- return NULL;
+ goto out;
}
__set_bit(channel, channel_usage);
ch = &dma_channels[channel];
ch->mode = mode;
+
+out:
+ mutex_unlock(&tegra_dma_lock);
return ch;
}
EXPORT_SYMBOL(tegra_dma_allocate_channel);
@@ -372,22 +369,27 @@ void tegra_dma_free_channel(struct tegra_dma_channel *ch)
if (ch->mode & TEGRA_DMA_SHARED)
return;
tegra_dma_cancel(ch);
+ mutex_lock(&tegra_dma_lock);
__clear_bit(ch->id, channel_usage);
+ mutex_unlock(&tegra_dma_lock);
}
EXPORT_SYMBOL(tegra_dma_free_channel);
static void tegra_dma_update_hw_partial(struct tegra_dma_channel *ch,
struct tegra_dma_req *req)
{
+ u32 apb_ptr;
+ u32 ahb_ptr;
+
if (req->to_memory) {
- ch->apb_ptr = req->source_addr;
- ch->ahb_ptr = req->dest_addr;
+ apb_ptr = req->source_addr;
+ ahb_ptr = req->dest_addr;
} else {
- ch->apb_ptr = req->dest_addr;
- ch->ahb_ptr = req->source_addr;
+ apb_ptr = req->dest_addr;
+ ahb_ptr = req->source_addr;
}
- writel(ch->apb_ptr, ch->addr + APB_DMA_CHAN_APB_PTR);
- writel(ch->ahb_ptr, ch->addr + APB_DMA_CHAN_AHB_PTR);
+ writel(apb_ptr, ch->addr + APB_DMA_CHAN_APB_PTR);
+ writel(ahb_ptr, ch->addr + APB_DMA_CHAN_AHB_PTR);
req->status = TEGRA_DMA_REQ_INFLIGHT;
return;
@@ -401,38 +403,39 @@ static void tegra_dma_update_hw(struct tegra_dma_channel *ch,
int ahb_bus_width;
int apb_bus_width;
int index;
- unsigned long csr;
+ u32 ahb_seq;
+ u32 apb_seq;
+ u32 ahb_ptr;
+ u32 apb_ptr;
+ u32 csr;
+
+ csr = CSR_IE_EOC | CSR_FLOW;
+ ahb_seq = AHB_SEQ_INTR_ENB | AHB_SEQ_BURST_1;
+ apb_seq = 0;
- ch->csr |= CSR_FLOW;
- ch->csr &= ~CSR_REQ_SEL_MASK;
- ch->csr |= req->req_sel << CSR_REQ_SEL_SHIFT;
- ch->ahb_seq &= ~AHB_SEQ_BURST_MASK;
- ch->ahb_seq |= AHB_SEQ_BURST_1;
+ csr |= req->req_sel << CSR_REQ_SEL_SHIFT;
/* One shot mode is always single buffered,
* continuous mode is always double buffered
* */
if (ch->mode & TEGRA_DMA_MODE_ONESHOT) {
- ch->csr |= CSR_ONCE;
- ch->ahb_seq &= ~AHB_SEQ_DBL_BUF;
- ch->csr &= ~CSR_WCOUNT_MASK;
- ch->csr |= ((req->size>>2) - 1) << CSR_WCOUNT_SHIFT;
+ csr |= CSR_ONCE;
+ ch->req_transfer_count = (req->size >> 2) - 1;
} else {
- ch->csr &= ~CSR_ONCE;
- ch->ahb_seq |= AHB_SEQ_DBL_BUF;
+ ahb_seq |= AHB_SEQ_DBL_BUF;
/* In double buffered mode, we set the size to half the
* requested size and interrupt when half the buffer
* is full */
- ch->csr &= ~CSR_WCOUNT_MASK;
- ch->csr |= ((req->size>>3) - 1) << CSR_WCOUNT_SHIFT;
+ ch->req_transfer_count = (req->size >> 3) - 1;
}
+ csr |= ch->req_transfer_count << CSR_WCOUNT_SHIFT;
+
if (req->to_memory) {
- ch->csr &= ~CSR_DIR;
- ch->apb_ptr = req->source_addr;
- ch->ahb_ptr = req->dest_addr;
+ apb_ptr = req->source_addr;
+ ahb_ptr = req->dest_addr;
apb_addr_wrap = req->source_wrap;
ahb_addr_wrap = req->dest_wrap;
@@ -440,9 +443,9 @@ static void tegra_dma_update_hw(struct tegra_dma_channel *ch,
ahb_bus_width = req->dest_bus_width;
} else {
- ch->csr |= CSR_DIR;
- ch->apb_ptr = req->dest_addr;
- ch->ahb_ptr = req->source_addr;
+ csr |= CSR_DIR;
+ apb_ptr = req->dest_addr;
+ ahb_ptr = req->source_addr;
apb_addr_wrap = req->dest_wrap;
ahb_addr_wrap = req->source_wrap;
@@ -461,8 +464,7 @@ static void tegra_dma_update_hw(struct tegra_dma_channel *ch,
index++;
} while (index < ARRAY_SIZE(apb_addr_wrap_table));
BUG_ON(index == ARRAY_SIZE(apb_addr_wrap_table));
- ch->apb_seq &= ~APB_SEQ_WRAP_MASK;
- ch->apb_seq |= index << APB_SEQ_WRAP_SHIFT;
+ apb_seq |= index << APB_SEQ_WRAP_SHIFT;
/* set address wrap for AHB size */
index = 0;
@@ -472,55 +474,42 @@ static void tegra_dma_update_hw(struct tegra_dma_channel *ch,
index++;
} while (index < ARRAY_SIZE(ahb_addr_wrap_table));
BUG_ON(index == ARRAY_SIZE(ahb_addr_wrap_table));
- ch->ahb_seq &= ~AHB_SEQ_WRAP_MASK;
- ch->ahb_seq |= index << AHB_SEQ_WRAP_SHIFT;
+ ahb_seq |= index << AHB_SEQ_WRAP_SHIFT;
for (index = 0; index < ARRAY_SIZE(bus_width_table); index++) {
if (bus_width_table[index] == ahb_bus_width)
break;
}
BUG_ON(index == ARRAY_SIZE(bus_width_table));
- ch->ahb_seq &= ~AHB_SEQ_BUS_WIDTH_MASK;
- ch->ahb_seq |= index << AHB_SEQ_BUS_WIDTH_SHIFT;
+ ahb_seq |= index << AHB_SEQ_BUS_WIDTH_SHIFT;
for (index = 0; index < ARRAY_SIZE(bus_width_table); index++) {
if (bus_width_table[index] == apb_bus_width)
break;
}
BUG_ON(index == ARRAY_SIZE(bus_width_table));
- ch->apb_seq &= ~APB_SEQ_BUS_WIDTH_MASK;
- ch->apb_seq |= index << APB_SEQ_BUS_WIDTH_SHIFT;
-
- ch->csr |= CSR_IE_EOC;
+ apb_seq |= index << APB_SEQ_BUS_WIDTH_SHIFT;
- /* update hw registers with the shadow */
- writel(ch->csr, ch->addr + APB_DMA_CHAN_CSR);
- writel(ch->apb_seq, ch->addr + APB_DMA_CHAN_APB_SEQ);
- writel(ch->apb_ptr, ch->addr + APB_DMA_CHAN_APB_PTR);
- writel(ch->ahb_seq, ch->addr + APB_DMA_CHAN_AHB_SEQ);
- writel(ch->ahb_ptr, ch->addr + APB_DMA_CHAN_AHB_PTR);
+ writel(csr, ch->addr + APB_DMA_CHAN_CSR);
+ writel(apb_seq, ch->addr + APB_DMA_CHAN_APB_SEQ);
+ writel(apb_ptr, ch->addr + APB_DMA_CHAN_APB_PTR);
+ writel(ahb_seq, ch->addr + APB_DMA_CHAN_AHB_SEQ);
+ writel(ahb_ptr, ch->addr + APB_DMA_CHAN_AHB_PTR);
- csr = ch->csr | CSR_ENB;
+ csr |= CSR_ENB;
writel(csr, ch->addr + APB_DMA_CHAN_CSR);
req->status = TEGRA_DMA_REQ_INFLIGHT;
}
-static void tegra_dma_init_hw(struct tegra_dma_channel *ch)
-{
- /* One shot with an interrupt to CPU after transfer */
- ch->csr = CSR_ONCE | CSR_IE_EOC;
- ch->ahb_seq = AHB_SEQ_BUS_WIDTH_32 | AHB_SEQ_INTR_ENB;
- ch->apb_seq = APB_SEQ_BUS_WIDTH_32 | 1 << APB_SEQ_WRAP_SHIFT;
-}
-
static void handle_oneshot_dma(struct tegra_dma_channel *ch)
{
struct tegra_dma_req *req;
+ unsigned long irq_flags;
- spin_lock(&ch->lock);
+ spin_lock_irqsave(&ch->lock, irq_flags);
if (list_empty(&ch->list)) {
- spin_unlock(&ch->lock);
+ spin_unlock_irqrestore(&ch->lock, irq_flags);
return;
}
@@ -528,8 +517,7 @@ static void handle_oneshot_dma(struct tegra_dma_channel *ch)
if (req) {
int bytes_transferred;
- bytes_transferred =
- (ch->csr & CSR_WCOUNT_MASK) >> CSR_WCOUNT_SHIFT;
+ bytes_transferred = ch->req_transfer_count;
bytes_transferred += 1;
bytes_transferred <<= 2;
@@ -537,12 +525,12 @@ static void handle_oneshot_dma(struct tegra_dma_channel *ch)
req->bytes_transferred = bytes_transferred;
req->status = TEGRA_DMA_REQ_SUCCESS;
- spin_unlock(&ch->lock);
+ spin_unlock_irqrestore(&ch->lock, irq_flags);
/* Callback should be called without any lock */
pr_debug("%s: transferred %d bytes\n", __func__,
req->bytes_transferred);
req->complete(req);
- spin_lock(&ch->lock);
+ spin_lock_irqsave(&ch->lock, irq_flags);
}
if (!list_empty(&ch->list)) {
@@ -552,22 +540,55 @@ static void handle_oneshot_dma(struct tegra_dma_channel *ch)
if (req->status != TEGRA_DMA_REQ_INFLIGHT)
tegra_dma_update_hw(ch, req);
}
- spin_unlock(&ch->lock);
+ spin_unlock_irqrestore(&ch->lock, irq_flags);
}
static void handle_continuous_dma(struct tegra_dma_channel *ch)
{
struct tegra_dma_req *req;
+ unsigned long irq_flags;
- spin_lock(&ch->lock);
+ spin_lock_irqsave(&ch->lock, irq_flags);
if (list_empty(&ch->list)) {
- spin_unlock(&ch->lock);
+ spin_unlock_irqrestore(&ch->lock, irq_flags);
return;
}
req = list_entry(ch->list.next, typeof(*req), node);
if (req) {
if (req->buffer_status == TEGRA_DMA_REQ_BUF_STATUS_EMPTY) {
+ bool is_dma_ping_complete;
+ is_dma_ping_complete = (readl(ch->addr + APB_DMA_CHAN_STA)
+ & STA_PING_PONG) ? true : false;
+ if (req->to_memory)
+ is_dma_ping_complete = !is_dma_ping_complete;
+ /* Out of sync - Release current buffer */
+ if (!is_dma_ping_complete) {
+ int bytes_transferred;
+
+ bytes_transferred = ch->req_transfer_count;
+ bytes_transferred += 1;
+ bytes_transferred <<= 3;
+ req->buffer_status = TEGRA_DMA_REQ_BUF_STATUS_FULL;
+ req->bytes_transferred = bytes_transferred;
+ req->status = TEGRA_DMA_REQ_SUCCESS;
+ tegra_dma_stop(ch);
+
+ if (!list_is_last(&req->node, &ch->list)) {
+ struct tegra_dma_req *next_req;
+
+ next_req = list_entry(req->node.next,
+ typeof(*next_req), node);
+ tegra_dma_update_hw(ch, next_req);
+ }
+
+ list_del(&req->node);
+
+ /* DMA lock is NOT held when callbak is called */
+ spin_unlock_irqrestore(&ch->lock, irq_flags);
+ req->complete(req);
+ return;
+ }
/* Load the next request into the hardware, if available
* */
if (!list_is_last(&req->node, &ch->list)) {
@@ -580,7 +601,7 @@ static void handle_continuous_dma(struct tegra_dma_channel *ch)
req->buffer_status = TEGRA_DMA_REQ_BUF_STATUS_HALF_FULL;
req->status = TEGRA_DMA_REQ_SUCCESS;
/* DMA lock is NOT held when callback is called */
- spin_unlock(&ch->lock);
+ spin_unlock_irqrestore(&ch->lock, irq_flags);
if (likely(req->threshold))
req->threshold(req);
return;
@@ -591,8 +612,7 @@ static void handle_continuous_dma(struct tegra_dma_channel *ch)
* the second interrupt */
int bytes_transferred;
- bytes_transferred =
- (ch->csr & CSR_WCOUNT_MASK) >> CSR_WCOUNT_SHIFT;
+ bytes_transferred = ch->req_transfer_count;
bytes_transferred += 1;
bytes_transferred <<= 3;
@@ -602,7 +622,7 @@ static void handle_continuous_dma(struct tegra_dma_channel *ch)
list_del(&req->node);
/* DMA lock is NOT held when callbak is called */
- spin_unlock(&ch->lock);
+ spin_unlock_irqrestore(&ch->lock, irq_flags);
req->complete(req);
return;
@@ -610,7 +630,7 @@ static void handle_continuous_dma(struct tegra_dma_channel *ch)
BUG();
}
}
- spin_unlock(&ch->lock);
+ spin_unlock_irqrestore(&ch->lock, irq_flags);
}
static irqreturn_t dma_isr(int irq, void *data)
@@ -674,7 +694,6 @@ int __init tegra_dma_init(void)
spin_lock_init(&ch->lock);
INIT_LIST_HEAD(&ch->list);
- tegra_dma_init_hw(ch);
irq = INT_APB_DMA_CH0 + i;
ret = request_threaded_irq(irq, dma_isr, dma_thread_fn, 0,
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-23 13:04:51 +0000