Re: [PATCH] hw/sd/sdhci: Do not force sdhci_mmio_*_ops onto all SD controllers

[Guenter Roeck]

On 7/24/23 00:18, Bernhard Beschow wrote:
> Am 16. Juli 2023 19:53:37 UTC schrieb Bernhard Beschow <shentey@gmail.com>:
> > Am 10. Juli 2023 16:01:46 UTC schrieb Bernhard Beschow <shentey@gmail.com>:
> > > Am 10. Juli 2023 10:16:35 UTC schrieb "Philippe Mathieu-Daudé" 
> > > <philmd@linaro.org>:
> > > > On 9/7/23 10:09, Bernhard Beschow wrote:
> > > > > Since commit c0a55a0c9da2 "hw/sd/sdhci: Support big endian SD host controller
> > > > > interfaces" sdhci_common_realize() forces all SD card controllers to use either
> > > > > sdhci_mmio_le_ops or sdhci_mmio_be_ops, depending on the "endianness" property.
> > > > > However, there are device models which use different MMIO ops: TYPE_IMX_USDHC
> > > > > uses usdhc_mmio_ops and TYPE_S3C_SDHCI uses sdhci_s3c_mmio_ops.
> > > > >
> > > > > Forcing sdhci_mmio_le_ops breaks SD card handling on the "sabrelite" board, for
> > > > > example. Fix this by defaulting the io_ops to little endian and switch to big
> > > > > endian in sdhci_common_realize() only if there is a matchig big endian variant
> > > > > available.
> > > > >
> > > > > Fixes: c0a55a0c9da2 ("hw/sd/sdhci: Support big endian SD host controller
> > > > > interfaces")
> > > > >
> > > > > Signed-off-by: Bernhard Beschow <shentey@gmail.com>
> > > > > ---
> > > > >    hw/sd/sdhci.c | 8 +++++++-
> > > > >    1 file changed, 7 insertions(+), 1 deletion(-)
> > > > >
> > > > > diff --git a/hw/sd/sdhci.c b/hw/sd/sdhci.c
> > > > > index 6811f0f1a8..362c2c86aa 100644
> > > > > --- a/hw/sd/sdhci.c
> > > > > +++ b/hw/sd/sdhci.c
> > > > > @@ -1382,6 +1382,8 @@ void sdhci_initfn(SDHCIState *s)
> > > > >          s->insert_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, 
> > > > > sdhci_raise_insertion_irq, s);
> > > > >        s->transfer_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, 
> > > > > sdhci_data_transfer, s);
> > > > > +
> > > > > +    s->io_ops = &sdhci_mmio_le_ops;
> > > > >    }
> > > > >      void sdhci_uninitfn(SDHCIState *s)
> > > > > @@ -1399,9 +1401,13 @@ void sdhci_common_realize(SDHCIState *s, Error **errp)
> > > > >    
> > > >
> > > > What about simply keeping the same code guarded with 'if (!s->io_ops)'?
> > >
> > > I chose below approach since it provides an error message when one attempts to 
> > > set one of the other device models to BE rather than just silently ignoring it.
> > >
> > > Also, I didn't want to make the assumption that `s->io_ops == NULL` implied 
> > > that sdhci_mmio_*_ops is needed. That's similar material the bug fixed is made of, 
> > > so I wanted to prevent that in the first place by being more explicit.
> > >
> > > In combination with the new error message the limitations of the current code 
> > > become hopefully very apparent now, and at the same time should provide enough 
> > > hints for adding BE support to the other device models if ever needed.
> > >
> > > Best regards,
> > > Bernhard
> >
> > Ping
>
> Ping^2
>
> I would like to have the bug fixed in 8.1.

+1

Not that I care too much - I build qemu myself anyway and carry the patch 
locally -
but this really should get fixed.

Guenter