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
diff --git a/hw/sd/sd.c b/hw/sd/sd.c index 1f3eea6e84..4e09640852 100644 --- a/hw/sd/sd.c +++ b/hw/sd/sd.c @@ -1507,7 +1507,7 @@ static sd_rsp_type_t sd_normal_command(SDState *sd, SDRequest req) } sd->state = sd_sendingdata_state; - *(uint32_t *) sd->data = sd_wpbits(sd, req.arg); + stl_be_p(sd->data, sd_wpbits(sd, req.arg)); sd->data_start = addr; sd->data_offset = 0; return sd_r1;