On Fri, 28 Jun 2024 at 08:05, Philippe Mathieu-Daudé <philmd@linaro.org> wrote: > > Per sections 3.6.1 (SD Bus Protocol), 4.3.4 "Data Write" > 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 | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) I think Linux only uses this command in an error-recovery code path (which we should never get into since our emulated SD card has 100% reliability ;-)), which is probably why we haven't noticed this before. Reviewed-by: Peter Maydell <peter.maydell@linaro.org> thanks -- PMM
diff --git a/hw/sd/sd.c b/hw/sd/sd.c index 4e09640852..1f37d9c93a 100644 --- a/hw/sd/sd.c +++ b/hw/sd/sd.c @@ -1668,8 +1668,7 @@ static sd_rsp_type_t sd_app_command(SDState *sd, case 22: /* ACMD22: SEND_NUM_WR_BLOCKS */ switch (sd->state) { case sd_transfer_state: - *(uint32_t *) sd->data = sd->blk_written; - + stl_be_p(sd->data, sd->blk_written); sd->state = sd_sendingdata_state; sd->data_start = 0; sd->data_offset = 0;