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fsldma: reduce kernel text size
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Some of the functions are written in a way where they use multiple reads
and writes where a single read/write pair could suffice. This shrinks the
kernel text size measurably, while making the functions easier to
understand.

add/remove: 0/0 grow/shrink: 1/4 up/down: 4/-196 (-192)
function                                     old     new   delta
fsl_chan_set_request_count                   120     124      +4
dma_halt                                     300     272     -28
fsl_chan_set_src_loop_size                   208     156     -52
fsl_chan_set_dest_loop_size                  208     156     -52
fsl_chan_xfer_ld_queue                       500     436     -64

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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Ira Snyder authored and Dan Williams committed Feb 2, 2010
1 parent abe94c7 commit 272ca65
Showing 1 changed file with 45 additions and 38 deletions.
83 changes: 45 additions & 38 deletions drivers/dma/fsldma.c
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Original file line number Diff line number Diff line change
Expand Up @@ -143,43 +143,45 @@ static int dma_is_idle(struct fsl_dma_chan *fsl_chan)

static void dma_start(struct fsl_dma_chan *fsl_chan)
{
u32 mr_set = 0;

if (fsl_chan->feature & FSL_DMA_CHAN_PAUSE_EXT) {
DMA_OUT(fsl_chan, &fsl_chan->reg_base->bcr, 0, 32);
mr_set |= FSL_DMA_MR_EMP_EN;
} else if ((fsl_chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX) {
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32)
& ~FSL_DMA_MR_EMP_EN, 32);
u32 mode;

mode = DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32);

if ((fsl_chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX) {
if (fsl_chan->feature & FSL_DMA_CHAN_PAUSE_EXT) {
DMA_OUT(fsl_chan, &fsl_chan->reg_base->bcr, 0, 32);
mode |= FSL_DMA_MR_EMP_EN;
} else {
mode &= ~FSL_DMA_MR_EMP_EN;
}
}

if (fsl_chan->feature & FSL_DMA_CHAN_START_EXT)
mr_set |= FSL_DMA_MR_EMS_EN;
mode |= FSL_DMA_MR_EMS_EN;
else
mr_set |= FSL_DMA_MR_CS;
mode |= FSL_DMA_MR_CS;

DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32)
| mr_set, 32);
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, mode, 32);
}

static void dma_halt(struct fsl_dma_chan *fsl_chan)
{
u32 mode;
int i;

DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) | FSL_DMA_MR_CA,
32);
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) & ~(FSL_DMA_MR_CS
| FSL_DMA_MR_EMS_EN | FSL_DMA_MR_CA), 32);
mode = DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32);
mode |= FSL_DMA_MR_CA;
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, mode, 32);

mode &= ~(FSL_DMA_MR_CS | FSL_DMA_MR_EMS_EN | FSL_DMA_MR_CA);
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, mode, 32);

for (i = 0; i < 100; i++) {
if (dma_is_idle(fsl_chan))
break;
udelay(10);
}

if (i >= 100 && !dma_is_idle(fsl_chan))
dev_err(fsl_chan->dev, "DMA halt timeout!\n");
}
Expand Down Expand Up @@ -231,22 +233,23 @@ static void append_ld_queue(struct fsl_dma_chan *fsl_chan,
*/
static void fsl_chan_set_src_loop_size(struct fsl_dma_chan *fsl_chan, int size)
{
u32 mode;

mode = DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32);

switch (size) {
case 0:
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) &
(~FSL_DMA_MR_SAHE), 32);
mode &= ~FSL_DMA_MR_SAHE;
break;
case 1:
case 2:
case 4:
case 8:
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) |
FSL_DMA_MR_SAHE | (__ilog2(size) << 14),
32);
mode |= FSL_DMA_MR_SAHE | (__ilog2(size) << 14);
break;
}

DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, mode, 32);
}

/**
Expand All @@ -262,22 +265,23 @@ static void fsl_chan_set_src_loop_size(struct fsl_dma_chan *fsl_chan, int size)
*/
static void fsl_chan_set_dest_loop_size(struct fsl_dma_chan *fsl_chan, int size)
{
u32 mode;

mode = DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32);

switch (size) {
case 0:
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) &
(~FSL_DMA_MR_DAHE), 32);
mode &= ~FSL_DMA_MR_DAHE;
break;
case 1:
case 2:
case 4:
case 8:
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) |
FSL_DMA_MR_DAHE | (__ilog2(size) << 16),
32);
mode |= FSL_DMA_MR_DAHE | (__ilog2(size) << 16);
break;
}

DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, mode, 32);
}

/**
Expand All @@ -294,11 +298,14 @@ static void fsl_chan_set_dest_loop_size(struct fsl_dma_chan *fsl_chan, int size)
*/
static void fsl_chan_set_request_count(struct fsl_dma_chan *fsl_chan, int size)
{
u32 mode;

BUG_ON(size > 1024);
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32)
| ((__ilog2(size) << 24) & 0x0f000000),
32);

mode = DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32);
mode |= (__ilog2(size) << 24) & 0x0f000000;

DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, mode, 32);
}

/**
Expand Down

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