diff options
author | Joshua Clayton <stillcompiling@gmail.com> | 2017-06-14 18:36:32 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-07-17 18:26:14 +0300 |
commit | fcfe18f885f6a2a7e906546fe709fccfda73a4b1 (patch) | |
tree | ad020505f61a68d1cd2f198d32ebeead952a834b /drivers/fpga | |
parent | 3b88da4aba2549497ac8868877562f1b1913ca62 (diff) | |
download | linux-fcfe18f885f6a2a7e906546fe709fccfda73a4b1.tar.xz |
fpga-manager: altera-ps-spi: use bitrev8x4
Speed up bit reversal by using hardware bit reversal
Add extra code to handle less than 4byte remnants, if any
Signed-off-by: Joshua Clayton <stillcompiling@gmail.com>
Signed-off-by: Alan Tull <atull@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/fpga')
-rw-r--r-- | drivers/fpga/altera-ps-spi.c | 19 |
1 files changed, 15 insertions, 4 deletions
diff --git a/drivers/fpga/altera-ps-spi.c b/drivers/fpga/altera-ps-spi.c index 0db8def668ed..14f14efdf0d5 100644 --- a/drivers/fpga/altera-ps-spi.c +++ b/drivers/fpga/altera-ps-spi.c @@ -149,12 +149,23 @@ static int altera_ps_write_init(struct fpga_manager *mgr, static void rev_buf(char *buf, size_t len) { - const char *fw_end = (buf + len); + u32 *fw32 = (u32 *)buf; + size_t extra_bytes = (len & 0x03); + const u32 *fw_end = (u32 *)(buf + len - extra_bytes); /* set buffer to lsb first */ - while (buf < fw_end) { - *buf = bitrev8(*buf); - buf++; + while (fw32 < fw_end) { + *fw32 = bitrev8x4(*fw32); + fw32++; + } + + if (extra_bytes) { + buf = (char *)fw_end; + while (extra_bytes) { + *buf = bitrev8(*buf); + buf++; + extra_bytes--; + } } } |