Yes, there's SD and MMC buses. It looks like the current code only supports
mmc ("soc->mmc.sdhci") but not the sd ("soc->sd.sdhci").
It's probably good to make the bus number a parameter as well and use them
to distinguish. We might need a separate patch to do that.
On Wed, Nov 17, 2021 at 8:54 AM Havard Skinnemoen <hskinnem...@google.com>
wrote:
> On Wed, Nov 17, 2021 at 8:34 AM Markus Armbruster <arm...@redhat.com>
> wrote:
> >
> > drive_get_next() is basically a bad idea. It returns the "next" block
> > backend of a certain interface type. "Next" means bus=0,unit=N, where
> > subsequent calls count N up from zero, per interface type.
> >
> > This lets you define unit numbers implicitly by execution order. If the
> > order changes, or new calls appear "in the middle", unit numbers change.
> > ABI break. Hard to spot in review.
> >
> > Machine "quanta-gbs-bmc" connects just one backend with
> > drive_get_next(), but with a helper function. Change it to use
> > drive_get() directly. This makes the unit numbers explicit in the
> > code.
> >
> > Cc: Havard Skinnemoen <hskinnem...@google.com>
> > Cc: Tyrone Ting <kft...@nuvoton.com>
> > Cc: Peter Maydell <peter.mayd...@linaro.org>
> > Cc: qemu-...@nongnu.org
> > Signed-off-by: Markus Armbruster <arm...@redhat.com>
> > ---
> > hw/arm/npcm7xx_boards.c | 6 +++---
> > 1 file changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/hw/arm/npcm7xx_boards.c b/hw/arm/npcm7xx_boards.c
> > index dec7d16ae5..d8a49e4e85 100644
> > --- a/hw/arm/npcm7xx_boards.c
> > +++ b/hw/arm/npcm7xx_boards.c
> > @@ -84,9 +84,9 @@ static void npcm7xx_connect_dram(NPCM7xxState *soc,
> MemoryRegion *dram)
> > &error_abort);
> > }
> >
> > -static void sdhci_attach_drive(SDHCIState *sdhci)
> > +static void sdhci_attach_drive(SDHCIState *sdhci, int unit)
> > {
> > - DriveInfo *di = drive_get_next(IF_SD);
> > + DriveInfo *di = drive_get(IF_SD, 0, unit);
>
> +Hao Wu IIRC the chip has separate SD and eMMC buses. Would it make
> sense to take the bus number as a parameter as well? Is bus 0 the
> right one to use in this case?
>
> The existing code always uses bus 0, so this is an improvement either way.
>
> Reviewed-by: Havard Skinnemoen <hskinnem...@google.com>
>
> > BlockBackend *blk = di ? blk_by_legacy_dinfo(di) : NULL;
> >
> > BusState *bus = qdev_get_child_bus(DEVICE(sdhci), "sd-bus");
> > @@ -374,7 +374,7 @@ static void quanta_gbs_init(MachineState *machine)
> > drive_get(IF_MTD, 0, 0));
> >
> > quanta_gbs_i2c_init(soc);
> > - sdhci_attach_drive(&soc->mmc.sdhci);
> > + sdhci_attach_drive(&soc->mmc.sdhci, 0);
> > npcm7xx_load_kernel(machine, soc);
> > }
> >
> > --
> > 2.31.1
> >
>
