Commit 22843545 authored by Lior Amsalem's avatar Lior Amsalem Committed by Vinod Koul

dma: mv_xor: Add support for DMA_INTERRUPT

The driver is capable of supporting DMA_INTERRUPT by issuing a dummy 128-byte
transfer. This helps removing a poll in the async_tx stack, replacing it with
a completion interrupt.
Signed-off-by: default avatarLior Amsalem <alior@marvell.com>
Signed-off-by: default avatarEzequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: default avatarVinod Koul <vinod.koul@intel.com>
parent 37380b98
...@@ -538,6 +538,24 @@ mv_xor_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, ...@@ -538,6 +538,24 @@ mv_xor_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
return mv_xor_prep_dma_xor(chan, dest, &src, 1, len, flags); return mv_xor_prep_dma_xor(chan, dest, &src, 1, len, flags);
} }
static struct dma_async_tx_descriptor *
mv_xor_prep_dma_interrupt(struct dma_chan *chan, unsigned long flags)
{
struct mv_xor_chan *mv_chan = to_mv_xor_chan(chan);
dma_addr_t src, dest;
size_t len;
src = mv_chan->dummy_src_addr;
dest = mv_chan->dummy_dst_addr;
len = MV_XOR_MIN_BYTE_COUNT;
/*
* We implement the DMA_INTERRUPT operation as a minimum sized
* XOR operation with a single dummy source address.
*/
return mv_xor_prep_dma_xor(chan, dest, &src, 1, len, flags);
}
static void mv_xor_free_chan_resources(struct dma_chan *chan) static void mv_xor_free_chan_resources(struct dma_chan *chan)
{ {
struct mv_xor_chan *mv_chan = to_mv_xor_chan(chan); struct mv_xor_chan *mv_chan = to_mv_xor_chan(chan);
...@@ -881,6 +899,10 @@ static int mv_xor_channel_remove(struct mv_xor_chan *mv_chan) ...@@ -881,6 +899,10 @@ static int mv_xor_channel_remove(struct mv_xor_chan *mv_chan)
dma_free_coherent(dev, MV_XOR_POOL_SIZE, dma_free_coherent(dev, MV_XOR_POOL_SIZE,
mv_chan->dma_desc_pool_virt, mv_chan->dma_desc_pool); mv_chan->dma_desc_pool_virt, mv_chan->dma_desc_pool);
dma_unmap_single(dev, mv_chan->dummy_src_addr,
MV_XOR_MIN_BYTE_COUNT, DMA_FROM_DEVICE);
dma_unmap_single(dev, mv_chan->dummy_dst_addr,
MV_XOR_MIN_BYTE_COUNT, DMA_TO_DEVICE);
list_for_each_entry_safe(chan, _chan, &mv_chan->dmadev.channels, list_for_each_entry_safe(chan, _chan, &mv_chan->dmadev.channels,
device_node) { device_node) {
...@@ -910,6 +932,16 @@ mv_xor_channel_add(struct mv_xor_device *xordev, ...@@ -910,6 +932,16 @@ mv_xor_channel_add(struct mv_xor_device *xordev,
dma_dev = &mv_chan->dmadev; dma_dev = &mv_chan->dmadev;
/*
* These source and destination dummy buffers are used to implement
* a DMA_INTERRUPT operation as a minimum-sized XOR operation.
* Hence, we only need to map the buffers at initialization-time.
*/
mv_chan->dummy_src_addr = dma_map_single(dma_dev->dev,
mv_chan->dummy_src, MV_XOR_MIN_BYTE_COUNT, DMA_FROM_DEVICE);
mv_chan->dummy_dst_addr = dma_map_single(dma_dev->dev,
mv_chan->dummy_dst, MV_XOR_MIN_BYTE_COUNT, DMA_TO_DEVICE);
/* allocate coherent memory for hardware descriptors /* allocate coherent memory for hardware descriptors
* note: writecombine gives slightly better performance, but * note: writecombine gives slightly better performance, but
* requires that we explicitly flush the writes * requires that we explicitly flush the writes
...@@ -934,6 +966,8 @@ mv_xor_channel_add(struct mv_xor_device *xordev, ...@@ -934,6 +966,8 @@ mv_xor_channel_add(struct mv_xor_device *xordev,
dma_dev->dev = &pdev->dev; dma_dev->dev = &pdev->dev;
/* set prep routines based on capability */ /* set prep routines based on capability */
if (dma_has_cap(DMA_INTERRUPT, dma_dev->cap_mask))
dma_dev->device_prep_dma_interrupt = mv_xor_prep_dma_interrupt;
if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask))
dma_dev->device_prep_dma_memcpy = mv_xor_prep_dma_memcpy; dma_dev->device_prep_dma_memcpy = mv_xor_prep_dma_memcpy;
if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) { if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
......
...@@ -28,6 +28,9 @@ ...@@ -28,6 +28,9 @@
#define MV_XOR_THRESHOLD 1 #define MV_XOR_THRESHOLD 1
#define MV_XOR_MAX_CHANNELS 2 #define MV_XOR_MAX_CHANNELS 2
#define MV_XOR_MIN_BYTE_COUNT SZ_128
#define MV_XOR_MAX_BYTE_COUNT (SZ_16M - 1)
/* Values for the XOR_CONFIG register */ /* Values for the XOR_CONFIG register */
#define XOR_OPERATION_MODE_XOR 0 #define XOR_OPERATION_MODE_XOR 0
#define XOR_OPERATION_MODE_MEMCPY 2 #define XOR_OPERATION_MODE_MEMCPY 2
...@@ -116,6 +119,9 @@ struct mv_xor_chan { ...@@ -116,6 +119,9 @@ struct mv_xor_chan {
struct list_head all_slots; struct list_head all_slots;
int slots_allocated; int slots_allocated;
struct tasklet_struct irq_tasklet; struct tasklet_struct irq_tasklet;
char dummy_src[MV_XOR_MIN_BYTE_COUNT];
char dummy_dst[MV_XOR_MIN_BYTE_COUNT];
dma_addr_t dummy_src_addr, dummy_dst_addr;
}; };
/** /**
...@@ -184,9 +190,4 @@ struct mv_xor_desc { ...@@ -184,9 +190,4 @@ struct mv_xor_desc {
#define mv_hw_desc_slot_idx(hw_desc, idx) \ #define mv_hw_desc_slot_idx(hw_desc, idx) \
((void *)(((unsigned long)hw_desc) + ((idx) << 5))) ((void *)(((unsigned long)hw_desc) + ((idx) << 5)))
#define MV_XOR_MIN_BYTE_COUNT (128)
#define XOR_MAX_BYTE_COUNT ((16 * 1024 * 1024) - 1)
#define MV_XOR_MAX_BYTE_COUNT XOR_MAX_BYTE_COUNT
#endif #endif
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