Re: [U-Boot] [PATCH] drivers/block/systemace: fixes read/write words for bus width = 8

Hi Wolfgang,

I've already sent V2 patch with only 1 chunk and updated comments to the mailing list.

-Alexey 03.01.2013 16:00 пользователь "Wolfgang Denk" wd@denx.de написал:

Dear Alexey Brodkin,

In message 1357137512-8618-1-git-send-email-alexey.brodkin@gmail.com you wrote:

...

From: Alexey Brodkin abrodkin@synopsys.com

Current implementation works fine for bus width = 16 bits because we never get into "if" branch.

If one sets width to 8 bits there will be 2 consequent data accesses (read/write):

1. Correct data access for 8-bit bus
2. Unconditional (and in this case incorrect) data access as if data bus

is 16-bit wide

Signed-off-by: Alexey Brodkin abrodkin@synopsys.com

drivers/block/systemace.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/block/systemace.c b/drivers/block/systemace.c index 247cf06..88561a7 100644 --- a/drivers/block/systemace.c +++ b/drivers/block/systemace.c @@ -66,7 +66,8 @@ static void ace_writew(u16 val, unsigned off) writeb(val >> 8, base + off + 1); #endif }

• out16(base + off, val);
  

• else
  

•         out16(base + off, val);
  

}

I agree with this first chunk.

...

static u16 ace_readw(unsigned off) @@ -78,8 +79,8 @@ static u16 ace_readw(unsigned off) return readb(base + off) | (readb(base + off + 1) << 8); #endif }

• return in16(base + off);
  

• else
  

•         return in16(base + off);
  

}

But please drop this second one; the "else" is not necessary and adds only unneeded nesting.

Best regards,

Wolfgang Denk

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