Re: [PATCH] spi: aspeed: Fix window offset of CE1

[Cédric Le Goater]

On 10/17/22 00:43, Joel Stanley wrote:
> On Sun, 16 Oct 2022 at 15:57, Cédric Le Goater <clg@xxxxxxxx> wrote:
> > The offset value of the mapping window in the kernel structure is
> > calculated using the value of the previous window offset. This doesn't
> > reflect how the HW is configured and can lead to erroneous setting of
> > the second flash device (CE1).
>
> So .offset is expected to be the absolute address of the window, and
> this was okay for the 2400/2500 but was broken on the 2600?

the aspeed_spi_get_windows() routine collects in an array the window/decoding
range setting for each CS, and the offset for CS1 and above is computed from
the offset/size of the previous CS. But this makes an assumption on the fact
ranges are contiguous, which is not necessarily how the HW is configured.

C.

> Reviewed-by: Joel Stanley <joel@xxxxxxxxx>
>
>
> > Cc: Chin-Ting Kuo <chin-ting_kuo@xxxxxxxxxxxxxx>
> > Fixes: e3228ed92893 ("spi: spi-mem: Convert Aspeed SMC driver to spi-mem")
> > Signed-off-by: Cédric Le Goater <clg@xxxxxxxx>
> > ---
> >   drivers/spi/spi-aspeed-smc.c | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/spi/spi-aspeed-smc.c b/drivers/spi/spi-aspeed-smc.c
> > index 33cefcf18392..b90571396a60 100644
> > --- a/drivers/spi/spi-aspeed-smc.c
> > +++ b/drivers/spi/spi-aspeed-smc.c
> > @@ -398,7 +398,7 @@ static void aspeed_spi_get_windows(struct aspeed_spi *aspi,
> >                  windows[cs].cs = cs;
> >                  windows[cs].size = data->segment_end(aspi, reg_val) -
> >                          data->segment_start(aspi, reg_val);
> > -               windows[cs].offset = cs ? windows[cs - 1].offset + windows[cs - 1].size : 0;
> > +               windows[cs].offset = data->segment_start(aspi, reg_val) - aspi->ahb_base_phy;
> >                  dev_vdbg(aspi->dev, "CE%d offset=0x%.8x size=0x%x\n", cs,
> >                           windows[cs].offset, windows[cs].size);
> >          }
> > --
> > 2.37.3