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Date: Sat, 17 Mar 2007 12:01:31 +0100
From: "andrzej zaborowski" <balrog@zabor.org>
Sender: balrogg@gmail.com
Subject: Re: [Qemu-devel] [PATCH] SecureDigital card emulation.
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To: Paul Brook <paul@codesourcery.com>
Cc: qemu-devel@nongnu.org

Hi,

On 17/03/07, Paul Brook <paul@codesourcery.com> wrote:
> On Friday 16 March 2007 20:59, andrzej zaborowski wrote:
> > Emulates an SD card with the full command set (no SPI mode though).
> > Should be more or less compliant with version 1.10 specification.
>
> I suspect your code only works on x86. Specifically things like:
>
> > +struct sd_response_r1_s {
> > +    uint8_t cmd;
> > +    uint32_t status;
> > +    uint8_t crc;
> > +};
>
> Will be a 12-byte struct on many hosts, and probably also breaks on big-endian
> hosts. AFAICS there's no way for the caller of sd_write_cmdline to figure out
> what type of response is returned (other than the length), so has to rely on
> doing a bitwise copy.

The card is supposed to return the type of response matching the
command that was issued, so the the caller does know the type and
doesn't do bitwise copy. If the card is broken and returns a different
response then we get garbage, exactly like on the actual hardware.

Regards,
Andrew