[PATCH v2 10/15] dmaengine: bcm2385: drop info parameters

From: Andrea della Porta
Date: Wed Mar 13 2024 - 10:11:02 EST


The parameters info and finalextrainfo are platform specific. So drop
them by generating them within bcm2835_dma_create_cb_chain().

Signed-off-by: Stefan Wahren <stefan.wahren@xxxxxxxx>
Signed-off-by: Andrea della Porta <andrea.porta@xxxxxxxx>
---
drivers/dma/bcm2835-dma.c | 80 +++++++++++++++++++--------------------
1 file changed, 39 insertions(+), 41 deletions(-)

diff --git a/drivers/dma/bcm2835-dma.c b/drivers/dma/bcm2835-dma.c
index 6f896bb1a4fe..03d97312a3f8 100644
--- a/drivers/dma/bcm2835-dma.c
+++ b/drivers/dma/bcm2835-dma.c
@@ -308,12 +308,11 @@ static void bcm2835_dma_desc_free(struct virt_dma_desc *vd)
bcm2835_dma_free_cb_chain(container_of(vd, struct bcm2835_desc, vd));
}

-static void bcm2835_dma_create_cb_set_length(struct bcm2835_chan *chan,
+static bool bcm2835_dma_create_cb_set_length(struct bcm2835_chan *chan,
struct bcm2835_dma_cb *control_block,
size_t len,
size_t period_len,
- size_t *total_len,
- u32 finalextrainfo)
+ size_t *total_len)
{
size_t max_len = bcm2835_dma_max_frame_length(chan);

@@ -322,7 +321,7 @@ static void bcm2835_dma_create_cb_set_length(struct bcm2835_chan *chan,

/* finished if we have no period_length */
if (!period_len)
- return;
+ return false;

/*
* period_len means: that we need to generate
@@ -336,7 +335,7 @@ static void bcm2835_dma_create_cb_set_length(struct bcm2835_chan *chan,
if (*total_len + control_block->length < period_len) {
/* update number of bytes in this period so far */
*total_len += control_block->length;
- return;
+ return false;
}

/* calculate the length that remains to reach period_length */
@@ -345,8 +344,7 @@ static void bcm2835_dma_create_cb_set_length(struct bcm2835_chan *chan,
/* reset total_length for next period */
*total_len = 0;

- /* add extrainfo bits in info */
- control_block->info |= finalextrainfo;
+ return true;
}

static inline size_t bcm2835_dma_count_frames_for_sg(struct bcm2835_chan *c,
@@ -371,7 +369,6 @@ static inline size_t bcm2835_dma_count_frames_for_sg(struct bcm2835_chan *c,
* @chan: the @dma_chan for which we run this
* @direction: the direction in which we transfer
* @cyclic: it is a cyclic transfer
- * @info: the default info bits to apply per controlblock
* @frames: number of controlblocks to allocate
* @src: the src address to assign
* @dst: the dst address to assign
@@ -379,25 +376,27 @@ static inline size_t bcm2835_dma_count_frames_for_sg(struct bcm2835_chan *c,
* @period_len: the period length when to apply @finalextrainfo
* in addition to the last transfer
* this will also break some control-blocks early
- * @finalextrainfo: additional bits in last controlblock
- * (or when period_len is reached in case of cyclic)
* @gfp: the GFP flag to use for allocation
+ * @flags
*/
static struct bcm2835_desc *bcm2835_dma_create_cb_chain(
struct dma_chan *chan,
enum dma_transfer_direction direction,
- bool cyclic, u32 info,
- u32 finalextrainfo,
- size_t frames, dma_addr_t src,
- dma_addr_t dst, size_t buf_len,
- size_t period_len, gfp_t gfp)
+ bool cyclic, size_t frames,
+ dma_addr_t src, dma_addr_t dst,
+ size_t buf_len, size_t period_len,
+ gfp_t gfp, unsigned long flags)
{
+ struct bcm2835_dmadev *od = to_bcm2835_dma_dev(chan->device);
struct bcm2835_chan *c = to_bcm2835_dma_chan(chan);
size_t len = buf_len, total_len;
size_t frame;
struct bcm2835_desc *d;
struct bcm2835_cb_entry *cb_entry;
struct bcm2835_dma_cb *control_block;
+ u32 extrainfo = bcm2835_dma_prepare_cb_extra(c, direction, cyclic,
+ false, flags);
+ bool zero_page = false;

if (!frames)
return NULL;
@@ -411,6 +410,14 @@ static struct bcm2835_desc *bcm2835_dma_create_cb_chain(
d->dir = direction;
d->cyclic = cyclic;

+ switch (direction) {
+ case DMA_MEM_TO_MEM:
+ case DMA_DEV_TO_MEM:
+ break;
+ default:
+ zero_page = src == od->zero_page;
+ }
+
/*
* Iterate over all frames, create a control block
* for each frame and link them together.
@@ -424,7 +431,8 @@ static struct bcm2835_desc *bcm2835_dma_create_cb_chain(

/* fill in the control block */
control_block = cb_entry->cb;
- control_block->info = info;
+ control_block->info = bcm2835_dma_prepare_cb_info(c, direction,
+ zero_page);
control_block->src = src;
control_block->dst = dst;
control_block->stride = 0;
@@ -432,10 +440,12 @@ static struct bcm2835_desc *bcm2835_dma_create_cb_chain(
/* set up length in control_block if requested */
if (buf_len) {
/* calculate length honoring period_length */
- bcm2835_dma_create_cb_set_length(c, control_block,
- len, period_len,
- &total_len,
- cyclic ? finalextrainfo : 0);
+ if (bcm2835_dma_create_cb_set_length(
+ c, control_block,
+ len, period_len, &total_len)) {
+ /* add extrainfo bits in info */
+ control_block->info |= extrainfo;
+ }

/* calculate new remaining length */
len -= control_block->length;
@@ -456,7 +466,9 @@ static struct bcm2835_desc *bcm2835_dma_create_cb_chain(
}

/* the last frame requires extra flags */
- d->cb_list[d->frames - 1].cb->info |= finalextrainfo;
+ extrainfo = bcm2835_dma_prepare_cb_extra(c, direction, cyclic, true,
+ flags);
+ d->cb_list[d->frames - 1].cb->info |= extrainfo;

/* detect a size mismatch */
if (buf_len && d->size != buf_len)
@@ -720,9 +732,6 @@ static struct dma_async_tx_descriptor *bcm2835_dma_prep_dma_memcpy(
{
struct bcm2835_chan *c = to_bcm2835_dma_chan(chan);
struct bcm2835_desc *d;
- u32 info = bcm2835_dma_prepare_cb_info(c, DMA_MEM_TO_MEM, false);
- u32 extra = bcm2835_dma_prepare_cb_extra(c, DMA_MEM_TO_MEM, false,
- true, 0);
size_t max_len = bcm2835_dma_max_frame_length(c);
size_t frames;

@@ -734,9 +743,8 @@ static struct dma_async_tx_descriptor *bcm2835_dma_prep_dma_memcpy(
frames = bcm2835_dma_frames_for_length(len, max_len);

/* allocate the CB chain - this also fills in the pointers */
- d = bcm2835_dma_create_cb_chain(chan, DMA_MEM_TO_MEM, false,
- info, extra, frames,
- src, dst, len, 0, GFP_KERNEL);
+ d = bcm2835_dma_create_cb_chain(chan, DMA_MEM_TO_MEM, false, frames,
+ src, dst, len, 0, GFP_KERNEL, 0);
if (!d)
return NULL;

@@ -752,8 +760,6 @@ static struct dma_async_tx_descriptor *bcm2835_dma_prep_slave_sg(
struct bcm2835_chan *c = to_bcm2835_dma_chan(chan);
struct bcm2835_desc *d;
dma_addr_t src = 0, dst = 0;
- u32 info = bcm2835_dma_prepare_cb_info(c, direction, false);
- u32 extra = bcm2835_dma_prepare_cb_extra(c, direction, false, true, 0);
size_t frames;

if (!is_slave_direction(direction)) {
@@ -776,10 +782,8 @@ static struct dma_async_tx_descriptor *bcm2835_dma_prep_slave_sg(
frames = bcm2835_dma_count_frames_for_sg(c, sgl, sg_len);

/* allocate the CB chain */
- d = bcm2835_dma_create_cb_chain(chan, direction, false,
- info, extra,
- frames, src, dst, 0, 0,
- GFP_NOWAIT);
+ d = bcm2835_dma_create_cb_chain(chan, direction, false, frames, src,
+ dst, 0, 0, GFP_NOWAIT, 0);
if (!d)
return NULL;

@@ -795,13 +799,9 @@ static struct dma_async_tx_descriptor *bcm2835_dma_prep_dma_cyclic(
size_t period_len, enum dma_transfer_direction direction,
unsigned long flags)
{
- struct bcm2835_dmadev *od = to_bcm2835_dma_dev(chan->device);
struct bcm2835_chan *c = to_bcm2835_dma_chan(chan);
struct bcm2835_desc *d;
dma_addr_t src, dst;
- u32 info = bcm2835_dma_prepare_cb_info(c, direction,
- buf_addr == od->zero_page);
- u32 extra = bcm2835_dma_prepare_cb_extra(c, direction, true, true, 0);
size_t max_len = bcm2835_dma_max_frame_length(c);
size_t frames;

@@ -852,10 +852,8 @@ static struct dma_async_tx_descriptor *bcm2835_dma_prep_dma_cyclic(
* note that we need to use GFP_NOWAIT, as the ALSA i2s dmaengine
* implementation calls prep_dma_cyclic with interrupts disabled.
*/
- d = bcm2835_dma_create_cb_chain(chan, direction, true,
- info, extra,
- frames, src, dst, buf_len,
- period_len, GFP_NOWAIT);
+ d = bcm2835_dma_create_cb_chain(chan, direction, true, frames, src, dst,
+ buf_len, period_len, GFP_NOWAIT, flags);
if (!d)
return NULL;

--
2.35.3