[PATCH v2] drivers/soc/litex: Add restart handler

[Stafford Horne]

On Mon, Jan 04, 2021 at 05:49:03PM +0100, Geert Uytterhoeven wrote:
> On Mon, Jan 4, 2021 at 5:45 PM Geert Uytterhoeven <geert at linux-m68k.org> wrote:
> > Let the LiteX SoC Controller a register a restart handler, which resets
> > the LiteX SoC by writing 1 to CSR_CTRL_RESET_ADDR.
> >
> > Signed-off-by: Geert Uytterhoeven <geert at linux-m68k.org>
> > ---
> > Tested with linux-on-litex-vexriscv.
> >
> > This patch is based on upstream, i.e. not on top of Gabriel Somlo's
> > "[PATCH v5 0/4] drivers/soc/litex: support 32-bit subregisters, 64-bit
> > CPUs"
> > (https://lore.kernel.org/lkml/20201227161320.2194830-1-gsomlo@gmail.com/)
> 
> Bummer, and that's why the RESET_REG_* definitions are no longer
> next to the SCRATCH_REG_* definitions :-(

If it helps I have accepted Gabriel's patches and put them onto for-next.

  https://github.com/openrisc/linux/commits/for-next

I am happy to take and test a patch based on that.  Or I can do the adjustments
to base the patch on that myself.  Let me know.

-Stafford

> Well, I assume that will be fixed by evolution ;-)
> 
> > v2:
> >   - Rebase on top of v5.11-rc1,
> >   - Change reset handler priority to recommended default value of 128
> >     (was 192).
> >
> > (v1 was not sent to a mailing list)
> > ---
> >  drivers/soc/litex/litex_soc_ctrl.c | 33 +++++++++++++++++++++++++++---
> >  1 file changed, 30 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/soc/litex/litex_soc_ctrl.c b/drivers/soc/litex/litex_soc_ctrl.c
> > index 1217cafdfd4d1d2b..d729ad50d4ffca5e 100644
> > --- a/drivers/soc/litex/litex_soc_ctrl.c
> > +++ b/drivers/soc/litex/litex_soc_ctrl.c
> > @@ -15,6 +15,11 @@
> >  #include <linux/module.h>
> >  #include <linux/errno.h>
> >  #include <linux/io.h>
> > +#include <linux/reboot.h>
> > +
> > +/* reset register located at the base address */
> > +#define RESET_REG_OFF           0x00
> > +#define RESET_REG_VALUE         0x00000001
> >
> >  /*
> >   * LiteX SoC Generator, depending on the configuration, can split a single
> 
> Gr{oetje,eeting}s,
> 
>                         Geert
> 
> -- 
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org
> 
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
>                                 -- Linus Torvalds