[PATCH 3/3] riscv: qemu: Implement is_flash_available() for MTD NOR

[Anup Patel]

On Tue, Jan 25, 2022 at 10:33 AM Bin Meng <bmeng.cn at gmail.com> wrote:
>
> On Sat, Jan 15, 2022 at 12:20 AM Anup Patel <apatel at ventanamicro.com> wrote:
> >
> > Currently, if MTD NOR is enabled then U-Boot tries to issue flash
> > commands even when CFI flash DT node is not present. This causes
> > access fault on RISC-V emulators or ISS which do not emulate CFI
> > flash. To handle this issue, we implement is_flash_available() for
> > qemu-riscv board which will return 1 only if CFI flash DT node is
> > present.
> >
> > Fixes: d248627f9d42 ("riscv: qemu: Enable MTD NOR flash support")
> > Signed-off-by: Anup Patel <apatel at ventanamicro.com>
> > ---
> >  board/emulation/qemu-riscv/qemu-riscv.c | 17 +++++++++++++++++
> >  1 file changed, 17 insertions(+)
> >
> > diff --git a/board/emulation/qemu-riscv/qemu-riscv.c b/board/emulation/qemu-riscv/qemu-riscv.c
> > index b0d9dd59b1..cd02dae1ab 100644
> > --- a/board/emulation/qemu-riscv/qemu-riscv.c
> > +++ b/board/emulation/qemu-riscv/qemu-riscv.c
> > @@ -8,6 +8,7 @@
> >  #include <env.h>
> >  #include <fdtdec.h>
> >  #include <image.h>
> > +#include <linux/libfdt.h>
> >  #include <log.h>
> >  #include <spl.h>
> >  #include <init.h>
> > @@ -16,6 +17,22 @@
> >
> >  DECLARE_GLOBAL_DATA_PTR;
> >
> > +#if IS_ENABLED(CONFIG_MTD_NOR_FLASH)
> > +int is_flash_available(void)
> > +{
> > +       if (IS_ENABLED(CONFIG_OF_SEPARATE) || IS_ENABLED(CONFIG_OF_BOARD)) {
>
> Why is this if statement needed?
>
> All QEMU riscv* defconfigs are using CONFIG_OF_BOARD, and there is no
> OF_SEPARATE use case since QEMU DTBs are always consumed by U-Boot.

I added the if statement for the case if someone disables CONFIG_OF_BOARD
but I can remove it if you insist.

>
> > +               const void *fdt =
> > +                       (const void *)(uintptr_t)gd->arch.firmware_fdt_addr;
> > +               int rc = fdt_node_offset_by_compatible(fdt, -1, "cfi-flash");
> > +
> > +               if (rc >= 0)
> > +                       return 1;
> > +       }
> > +
> > +       return 0;
> > +}
> > +#endif
> > +
> >  int board_init(void)
> >  {
> >         /*
>
> Regards,
> Bin

Regards,
Anup