Commit 049d0d38 authored by Vinod Koul's avatar Vinod Koul

Merge branch 'topic/axi' into for-linus

parents 5ddab696 008913db
......@@ -72,6 +72,9 @@
#define AXI_DMAC_FLAG_CYCLIC BIT(0)
/* The maximum ID allocated by the hardware is 31 */
#define AXI_DMAC_SG_UNUSED 32U
struct axi_dmac_sg {
dma_addr_t src_addr;
dma_addr_t dest_addr;
......@@ -80,6 +83,7 @@ struct axi_dmac_sg {
unsigned int dest_stride;
unsigned int src_stride;
unsigned int id;
bool schedule_when_free;
};
struct axi_dmac_desc {
......@@ -200,11 +204,21 @@ static void axi_dmac_start_transfer(struct axi_dmac_chan *chan)
}
sg = &desc->sg[desc->num_submitted];
/* Already queued in cyclic mode. Wait for it to finish */
if (sg->id != AXI_DMAC_SG_UNUSED) {
sg->schedule_when_free = true;
return;
}
desc->num_submitted++;
if (desc->num_submitted == desc->num_sgs)
chan->next_desc = NULL;
else
if (desc->num_submitted == desc->num_sgs) {
if (desc->cyclic)
desc->num_submitted = 0; /* Start again */
else
chan->next_desc = NULL;
} else {
chan->next_desc = desc;
}
sg->id = axi_dmac_read(dmac, AXI_DMAC_REG_TRANSFER_ID);
......@@ -220,9 +234,11 @@ static void axi_dmac_start_transfer(struct axi_dmac_chan *chan)
/*
* If the hardware supports cyclic transfers and there is no callback to
* call, enable hw cyclic mode to avoid unnecessary interrupts.
* call and only a single segment, enable hw cyclic mode to avoid
* unnecessary interrupts.
*/
if (chan->hw_cyclic && desc->cyclic && !desc->vdesc.tx.callback)
if (chan->hw_cyclic && desc->cyclic && !desc->vdesc.tx.callback &&
desc->num_sgs == 1)
flags |= AXI_DMAC_FLAG_CYCLIC;
axi_dmac_write(dmac, AXI_DMAC_REG_X_LENGTH, sg->x_len - 1);
......@@ -237,37 +253,52 @@ static struct axi_dmac_desc *axi_dmac_active_desc(struct axi_dmac_chan *chan)
struct axi_dmac_desc, vdesc.node);
}
static void axi_dmac_transfer_done(struct axi_dmac_chan *chan,
static bool axi_dmac_transfer_done(struct axi_dmac_chan *chan,
unsigned int completed_transfers)
{
struct axi_dmac_desc *active;
struct axi_dmac_sg *sg;
bool start_next = false;
active = axi_dmac_active_desc(chan);
if (!active)
return;
return false;
if (active->cyclic) {
vchan_cyclic_callback(&active->vdesc);
} else {
do {
sg = &active->sg[active->num_completed];
if (!(BIT(sg->id) & completed_transfers))
break;
active->num_completed++;
if (active->num_completed == active->num_sgs) {
do {
sg = &active->sg[active->num_completed];
if (sg->id == AXI_DMAC_SG_UNUSED) /* Not yet submitted */
break;
if (!(BIT(sg->id) & completed_transfers))
break;
active->num_completed++;
sg->id = AXI_DMAC_SG_UNUSED;
if (sg->schedule_when_free) {
sg->schedule_when_free = false;
start_next = true;
}
if (active->cyclic)
vchan_cyclic_callback(&active->vdesc);
if (active->num_completed == active->num_sgs) {
if (active->cyclic) {
active->num_completed = 0; /* wrap around */
} else {
list_del(&active->vdesc.node);
vchan_cookie_complete(&active->vdesc);
active = axi_dmac_active_desc(chan);
}
} while (active);
}
}
} while (active);
return start_next;
}
static irqreturn_t axi_dmac_interrupt_handler(int irq, void *devid)
{
struct axi_dmac *dmac = devid;
unsigned int pending;
bool start_next = false;
pending = axi_dmac_read(dmac, AXI_DMAC_REG_IRQ_PENDING);
if (!pending)
......@@ -281,10 +312,10 @@ static irqreturn_t axi_dmac_interrupt_handler(int irq, void *devid)
unsigned int completed;
completed = axi_dmac_read(dmac, AXI_DMAC_REG_TRANSFER_DONE);
axi_dmac_transfer_done(&dmac->chan, completed);
start_next = axi_dmac_transfer_done(&dmac->chan, completed);
}
/* Space has become available in the descriptor queue */
if (pending & AXI_DMAC_IRQ_SOT)
if ((pending & AXI_DMAC_IRQ_SOT) || start_next)
axi_dmac_start_transfer(&dmac->chan);
spin_unlock(&dmac->chan.vchan.lock);
......@@ -334,12 +365,16 @@ static void axi_dmac_issue_pending(struct dma_chan *c)
static struct axi_dmac_desc *axi_dmac_alloc_desc(unsigned int num_sgs)
{
struct axi_dmac_desc *desc;
unsigned int i;
desc = kzalloc(sizeof(struct axi_dmac_desc) +
sizeof(struct axi_dmac_sg) * num_sgs, GFP_NOWAIT);
if (!desc)
return NULL;
for (i = 0; i < num_sgs; i++)
desc->sg[i].id = AXI_DMAC_SG_UNUSED;
desc->num_sgs = num_sgs;
return desc;
......
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