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| author | Robert Jarzmik <robert.jarzmik@free.fr> | 2011-12-19 10:17:19 +0100 |
|---|---|---|
| committer | Sascha Hauer <s.hauer@pengutronix.de> | 2011-12-21 11:15:31 +0100 |
| commit | edd0f1cede7fd568035da7820b329432cdb2220a (patch) | |
| tree | 3105afe9328fce8d4b33224a1366f5b60435895c /drivers/mci/pxamci.c | |
| parent | 64aa9692c82071c0199b8a1403f2ee90d674cab7 (diff) | |
| download | barebox-edd0f1cede7fd568035da7820b329432cdb2220a.tar.gz barebox-edd0f1cede7fd568035da7820b329432cdb2220a.tar.xz | |
drivers/mci: pxa read data performance boost
Increase pxa reading performance by reading 4 bytes at a
time instead of 4 reads of 1 byte.
As the mci controller FIFO accepts reads on bytes, halfwords
or words, use words whenether possible.
The boost is for a 250KBytes file read and display (bmp):
- before: 6900ms
- after: 6000ms
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Diffstat (limited to 'drivers/mci/pxamci.c')
| -rw-r--r-- | drivers/mci/pxamci.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/drivers/mci/pxamci.c b/drivers/mci/pxamci.c index a3f8f228f8..1634a1d775 100644 --- a/drivers/mci/pxamci.c +++ b/drivers/mci/pxamci.c @@ -74,8 +74,9 @@ static void pxamci_setup_data(struct pxamci_host *host, struct mci_data *data) static int pxamci_read_data(struct pxamci_host *host, unsigned char *dst, unsigned len) { - int trf_len, ret = 0; + int trf_len, trf_len1, trf_len4, ret = 0; uint64_t start; + u32 *dst4; mci_dbg("dst=%p, len=%u\n", dst, len); while (!ret && len > 0) { @@ -85,8 +86,13 @@ static int pxamci_read_data(struct pxamci_host *host, unsigned char *dst, ret && !is_timeout(start, 10 * MSECOND);) if (mmc_readl(MMC_I_REG) & RXFIFO_RD_REQ) ret = 0; - for (; !ret && trf_len > 0; trf_len--, len--) + trf_len1 = trf_len % 4; + trf_len4 = trf_len / 4; + for (dst4 = (u32 *)dst; !ret && trf_len4 > 0; trf_len4--) + *dst4++ = mmc_readl(MMC_RXFIFO); + for (dst = (u8 *)dst4; !ret && trf_len1 > 0; trf_len1--) *dst++ = mmc_readb(MMC_RXFIFO); + len -= trf_len; } if (!ret) |