[PATCH 14/31] staging: mt7621-mmc: Start cleanup of msdc_dma_config
Christian Lütke-Stetzkamp
christian at lkamp.de
Wed Apr 18 15:27:33 UTC 2018
Currently the msdc_dma_config function has some variables, that are
not needed, uses the macro msdc_init_bd that is only used here and
does not use the for_each_sg iterator. That last fact could cause a
bug if the scatterlist is chained.
The function is changed to remove these things, but none of the
changes should change the behavior of it (despite the case of a linked
scatterlist).
Signed-off-by: Christian Lütke-Stetzkamp <christian at lkamp.de>
---
drivers/staging/mt7621-mmc/sd.c | 29 +++++++++++------------------
1 file changed, 11 insertions(+), 18 deletions(-)
diff --git a/drivers/staging/mt7621-mmc/sd.c b/drivers/staging/mt7621-mmc/sd.c
index ad1b8f38f11d..faa94be39297 100644
--- a/drivers/staging/mt7621-mmc/sd.c
+++ b/drivers/staging/mt7621-mmc/sd.c
@@ -209,15 +209,6 @@ static int msdc_rsp[] = {
((struct gpd *)_gpd)->blknum = blknum; \
} while (0)
-#define msdc_init_bd(_bd, blkpad, dwpad, dptr, dlen) \
- do { \
- BUG_ON(dlen > 0xFFFFUL); \
- ((struct bd *)_bd)->blkpad = blkpad; \
- ((struct bd *)_bd)->dwpad = dwpad; \
- ((struct bd *)_bd)->ptr = (void *)dptr; \
- ((struct bd *)_bd)->buflen = dlen; \
- } while (0)
-
#define msdc_txfifocnt() ((sdr_read32(MSDC_FIFOCS) & MSDC_FIFOCS_TXCNT) >> 16)
#define msdc_rxfifocnt() ((sdr_read32(MSDC_FIFOCS) & MSDC_FIFOCS_RXCNT) >> 0)
#define msdc_fifo_write32(v) sdr_write32(MSDC_TXDATA, (v))
@@ -1260,9 +1251,8 @@ static u8 msdc_dma_calcs(u8 *buf, u32 len)
static int msdc_dma_config(struct msdc_host *host, struct msdc_dma *dma)
{
u32 base = host->base;
- u32 sglen = dma->sglen;
//u32 i, j, num, bdlen, arg, xfersz;
- u32 j, num, bdlen;
+ u32 j, num;
u8 blkpad, dwpad, chksum;
struct scatterlist *sg = dma->sg;
struct gpd *gpd;
@@ -1291,12 +1281,11 @@ static int msdc_dma_config(struct msdc_host *host, struct msdc_dma *dma)
chksum = (dma->flags & DMA_FLAG_EN_CHKSUM) ? 1 : 0;
/* calculate the required number of gpd */
- num = (sglen + MAX_BD_PER_GPD - 1) / MAX_BD_PER_GPD;
+ num = (dma->sglen + MAX_BD_PER_GPD - 1) / MAX_BD_PER_GPD;
BUG_ON(num != 1);
gpd = dma->gpd;
bd = dma->bd;
- bdlen = sglen;
/* modify gpd*/
//gpd->intr = 0;
@@ -1306,19 +1295,23 @@ static int msdc_dma_config(struct msdc_host *host, struct msdc_dma *dma)
gpd->chksum = (chksum ? msdc_dma_calcs((u8 *)gpd, 16) : 0);
/* modify bd*/
- for (j = 0; j < bdlen; j++) {
- msdc_init_bd(&bd[j], blkpad, dwpad, sg_dma_address(sg), sg_dma_len(sg));
- if (j == bdlen - 1)
+ for_each_sg(dma->sg, sg, dma->sglen, j) {
+ bd[j].blkpad = blkpad;
+ bd[j].dwpad = dwpad;
+ bd[j].ptr = (void *)sg_dma_address(sg);
+ bd[j].buflen = sg_dma_len(sg);
+
+ if (j == dma->sglen - 1)
bd[j].eol = 1; /* the last bd */
else
bd[j].eol = 0;
+
bd[j].chksum = 0; /* checksume need to clear first */
bd[j].chksum = (chksum ? msdc_dma_calcs((u8 *)(&bd[j]), 16) : 0);
- sg++;
}
dma->used_gpd += 2;
- dma->used_bd += bdlen;
+ dma->used_bd += dma->sglen;
sdr_set_field(MSDC_DMA_CFG, MSDC_DMA_CFG_DECSEN, chksum);
sdr_set_field(MSDC_DMA_CTRL, MSDC_DMA_CTRL_BRUSTSZ,
--
2.16.1
More information about the devel
mailing list