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dmaengine/amba-pl08x: Add prep_single_byte_llis() routine

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Code for creating single byte llis is present at several places. Create a
routine to avoid code redundancy.

Also, we don't need one lli per single byte transfer, we can have single lli to
do all single byte transfer.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This commit is contained in:
Viresh Kumar 2011-08-05 15:32:39 +05:30 committed by Vinod Koul
parent fa6a940bf1
commit 03af500f74
1 changed files with 33 additions and 28 deletions
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61
drivers/dma/amba-pl08x.c
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@ -559,6 +559,14 @@ static void pl08x_fill_lli_for_desc(struct pl08x_lli_build_data *bd,
bd->remainder -= len;
}
static inline void prep_byte_width_lli(struct pl08x_lli_build_data *bd,
u32 *cctl, u32 len, int num_llis, size_t *total_bytes)
{
*cctl = pl08x_cctl_bits(*cctl, 1, 1, len);
pl08x_fill_lli_for_desc(bd, num_llis, len, *cctl);
(*total_bytes) += len;
}
/*
* This fills in the table of LLIs for the transfer descriptor
* Note that we assume we never have to change the burst sizes
@ -570,7 +578,7 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
struct pl08x_bus_data *mbus, *sbus;
struct pl08x_lli_build_data bd;
int num_llis = 0;
u32 cctl;
u32 cctl, early_bytes = 0;
size_t max_bytes_per_lli, total_bytes = 0;
struct pl08x_lli *llis_va;
@ -619,29 +627,27 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
mbus == &bd.srcbus ? "src" : "dst",
sbus == &bd.srcbus ? "src" : "dst");
if (txd->len < mbus->buswidth) {
/* Less than a bus width available - send as single bytes */
while (bd.remainder) {
dev_vdbg(&pl08x->adev->dev,
"%s single byte LLIs for a transfer of "
"less than a bus width (remain 0x%08x)\n",
__func__, bd.remainder);
cctl = pl08x_cctl_bits(cctl, 1, 1, 1);
pl08x_fill_lli_for_desc(&bd, num_llis++, 1, cctl);
total_bytes++;
}
} else {
/* Make one byte LLIs until master bus is aligned */
while ((mbus->addr) % (mbus->buswidth)) {
dev_vdbg(&pl08x->adev->dev,
"%s adjustment lli for less than bus width "
"(remain 0x%08x)\n",
__func__, bd.remainder);
cctl = pl08x_cctl_bits(cctl, 1, 1, 1);
pl08x_fill_lli_for_desc(&bd, num_llis++, 1, cctl);
total_bytes++;
}
/*
* Send byte by byte for following cases
* - Less than a bus width available
* - until master bus is aligned
*/
if (bd.remainder < mbus->buswidth)
early_bytes = bd.remainder;
else if ((mbus->addr) % (mbus->buswidth)) {
early_bytes = mbus->buswidth - (mbus->addr) % (mbus->buswidth);
if ((bd.remainder - early_bytes) < mbus->buswidth)
early_bytes = bd.remainder;
}
if (early_bytes) {
dev_vdbg(&pl08x->adev->dev, "%s byte width LLIs "
"(remain 0x%08x)\n", __func__, bd.remainder);
prep_byte_width_lli(&bd, &cctl, early_bytes, num_llis++,
&total_bytes);
}
if (bd.remainder) {
/*
* Master now aligned
* - if slave is not then we must set its width down
@ -692,13 +698,12 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
/*
* Send any odd bytes
*/
while (bd.remainder) {
cctl = pl08x_cctl_bits(cctl, 1, 1, 1);
if (bd.remainder) {
dev_vdbg(&pl08x->adev->dev,
"%s align with boundary, single odd byte (remain %zu)\n",
"%s align with boundary, send odd bytes (remain %zu)\n",
__func__, bd.remainder);
pl08x_fill_lli_for_desc(&bd, num_llis++, 1, cctl);
total_bytes++;
prep_byte_width_lli(&bd, &cctl, bd.remainder,
num_llis++, &total_bytes);
}
}