Re: [PATCH v42 02/98] hw/sd/sdcard: Use spec v3.01 by default

[Philippe Mathieu-Daudé]

On 28/6/24 10:14, Daniel P. Berrangé wrote:
> On Fri, Jun 28, 2024 at 09:00:38AM +0200, Philippe Mathieu-Daudé wrote:
> > Recent SDHCI expect cards to support the v3.01 spec
> > to negociate lower I/O voltage. Select it by default.
> >
> > Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> > Reviewed-by: Cédric Le Goater <clg@redhat.com>
> > ---
> >   hw/sd/sd.c | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/hw/sd/sd.c b/hw/sd/sd.c
> > index a48010cfc1..d0a1d5db18 100644
> > --- a/hw/sd/sd.c
> > +++ b/hw/sd/sd.c
> > @@ -2280,7 +2280,7 @@ static void sd_realize(DeviceState *dev, Error **errp)
> >   
> >   static Property sd_properties[] = {
> >       DEFINE_PROP_UINT8("spec_version", SDState,
> > -                      spec_version, SD_PHY_SPECv2_00_VERS),
> > +                      spec_version, SD_PHY_SPECv3_01_VERS),
>
> Shouldn't such a change be tied to machine type versions ?

I don't think so, SD cards are external to machines (like
CDROM you can use any brand). IOW machines only provide a
SD card reader, user can insert any card there.

SD specs are backward compatible. If host FW only knows
about v2.00 commands (spec is from 2006 btw) a v3.01 card
will works.

BTW latest spec is v9.10 from 2023. The more recent card
I bought supports spec v6.00 from 2018.