[U-Boot] [PATCH 3/3] mtd: rawnand: denali: Do not reset the block on SoCFPGA

[Masahiro Yamada]

On Tue, Nov 26, 2019 at 5:23 PM Marek Vasut <marex at denx.de> wrote:
>
> On 11/26/19 3:47 AM, Masahiro Yamada wrote:
> > On Thu, Nov 21, 2019 at 6:38 AM Marek Vasut wrote:
> >>
> >> Legacy kernel versions for SoCFPGA may not implement proper reset
> >> handling.
> >
> > What is "legacy kernel versions" ?
>
> Anything older than 5.x , which got proper reset handling, finally.


Really?
Could you tell the commit ID?



>
> >> Apply the same approach as SoCFPGA reset driver, check
> >> environment variable "socfpga_legacy_reset_compat", and if it is
> >> set, do not reset the IP before booting Linux. This way, even the
> >> older kernel versions can be booted by up to date U-Boot.
> >>
> >> Signed-off-by: Marek Vasut <marex at denx.de>
> >> Cc: Masahiro Yamada <yamada.masahiro at socionext.com>
> >> ---
> >>  drivers/mtd/nand/raw/denali_dt.c | 12 ++++++++++++
> >>  1 file changed, 12 insertions(+)
> >>
> >> diff --git a/drivers/mtd/nand/raw/denali_dt.c b/drivers/mtd/nand/raw/denali_dt.c
> >> index 2c9e249ab6..d35f2a3543 100644
> >> --- a/drivers/mtd/nand/raw/denali_dt.c
> >> +++ b/drivers/mtd/nand/raw/denali_dt.c
> >> @@ -148,6 +148,18 @@ static int denali_dt_remove(struct udevice *dev)
> >>  {
> >>         struct denali_nand_info *denali = dev_get_priv(dev);
> >>
> >> +#if CONFIG_IS_ENABLED(ARCH_SOCFPGA)
> >> +       /*
> >> +        * Legacy kernel versions do not implement proper reset handling on
> >> +        * SoCFPGA. To let those older kernel versions work, reuse the same
> >> +        * approach as the SoCFPGA reset driver does -- check environment
> >> +        * variable socfpga_legacy_reset_compat and avoid resetting the IP
> >> +        * before booting the kernel if it is set to 1.
> >> +        */
> >> +       if (env_get_ulong("socfpga_legacy_reset_compat", 10, 0))
> >> +               return 0;
> >> +#endif
> >> +
> >
> >
> > How about removing denali_dt_remove() entirely ?
>
> Fine by me.
>
> > Not only SOCFPGA, but also my boards are broken.
>
> How come ?

Because the Linux kernel version I am using
does not have the reset handling for the Denali driver.




>
> > I am really annoyed since the following commit:
> >
> >
> >
> >
> > commit ed784ac3822b7d7019679a41a17907296e2dadbe
> > Author:     Simon Goldschmidt <simon.k.r.goldschmidt at gmail.com>
> > AuthorDate: Fri Mar 1 20:12:34 2019 +0100
> > Commit:     Marek Vasut <marex at denx.de>
> > CommitDate: Wed Apr 17 22:20:16 2019 +0200
> >
> >     mtd: rawnand: denali: add reset handling
> >
> >     This adds reset handling to the devicetree-enabled Denali NAND driver.
> >
> >     For backwards compatibility, only a warning is printed when failing to
> >     get reset handles.
> >
> >     Signed-off-by: Simon Goldschmidt <simon.k.r.goldschmidt at gmail.com>
> >
> >
> >
> >>         return reset_release_bulk(&denali->resets);
> >>  }
>
> CCing Simon.
> _______________________________________________
> U-Boot mailing list
> U-Boot at lists.denx.de
> https://lists.denx.de/listinfo/u-boot



-- 
Best Regards
Masahiro Yamada