Re: [PATCH v42 07/98] hw/sd/sdcard: Send WRITE_PROT bits MSB first (CMD30)

[Peter Maydell]

On Fri, 28 Jun 2024 at 08:03, Philippe Mathieu-Daudé <philmd@linaro.org> wrote:
>
> Per sections 3.6.1 (SD Bus Protocol) and 7.3.2 (Responses):
>
>   In the CMD line the Most Significant Bit is transmitted first.
>
> Use the stl_be_p() helper to store the value in big-endian.
>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> Tested-by: Cédric Le Goater <clg@redhat.com>
> ---
> RFC because I'm surprised this has been unnoticed for 17 years
> (commit a1bb27b1e9 "initial SD card emulation", April 2007).
>
> Cc: Peter Maydell <peter.maydell@linaro.org>
> ---
>  hw/sd/sd.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

It looks like Linux never uses this command at all, which is
probably why we haven't noticed the issue.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

thanks
-- PMM