Re: [PATCH] RISC-V: simplify BUILTIN_DTB processing

From: Vitaly Wool
Date: Fri Jan 15 2021 - 15:19:49 EST


On Fri, Jan 15, 2021 at 11:43 AM Anup Patel <anup@xxxxxxxxxxxxxx> wrote:
>
> On Fri, Jan 15, 2021 at 3:18 PM Vitaly Wool <vitaly.wool@xxxxxxxxxxxx> wrote:
> >
> >
> >
> > On Fri, 15 Jan 2021, 10:39 Anup Patel, <anup@xxxxxxxxxxxxxx> wrote:
> >>
> >> On Tue, Jan 12, 2021 at 2:51 AM Vitaly Wool <vitaly.wool@xxxxxxxxxxxx> wrote:
> >> >
> >> > Provide __dtb_start as a parameter to setup_vm() in case
> >> > CONFIG_BUILTIN_DTB is true, so we don't have to duplicate
> >> > BUILTIN_DTB specific processing in MMU-enabled and MMU-disabled
> >> > versions of setup_vm().
> >> >
> >> > Signed-off-by: Vitaly Wool <vitaly.wool@xxxxxxxxxxxx>
> >> > ---
> >> > arch/riscv/kernel/head.S | 4 ++++
> >> > arch/riscv/mm/init.c | 4 ----
> >> > 2 files changed, 4 insertions(+), 4 deletions(-)
> >> >
> >> > diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
> >> > index 16e9941900c4..f5a9bad86e58 100644
> >> > --- a/arch/riscv/kernel/head.S
> >> > +++ b/arch/riscv/kernel/head.S
> >> > @@ -260,7 +260,11 @@ clear_bss_done:
> >> >
> >> > /* Initialize page tables and relocate to virtual addresses */
> >> > la sp, init_thread_union + THREAD_SIZE
> >> > +#ifdef CONFIG_BUILTIN_DTB
> >> > + la a0, __dtb_start
> >> > +#else
> >> > mv a0, s1
> >> > +#endif /* CONFIG_BUILTIN_DTB */
> >> > call setup_vm
> >> > #ifdef CONFIG_MMU
> >> > la a0, early_pg_dir
> >> > diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> >> > index 5b17f8d22f91..45faad7c4291 100644
> >> > --- a/arch/riscv/mm/init.c
> >> > +++ b/arch/riscv/mm/init.c
> >> > @@ -615,11 +615,7 @@ static void __init setup_vm_final(void)
> >> > #else
> >> > asmlinkage void __init setup_vm(uintptr_t dtb_pa)
> >> > {
> >> > -#ifdef CONFIG_BUILTIN_DTB
> >> > - dtb_early_va = (void *) __dtb_start;
> >> > -#else
> >> > dtb_early_va = (void *)dtb_pa;
> >> > -#endif
> >> > dtb_early_pa = dtb_pa;
> >> > }
> >> >
> >> > --
> >> > 2.20.1
> >> >
> >>
> >> We can avoid the early DTB mapping for MMU-enabled case when
> >> BUILTIN_DTB is enabled (same as previous discussion). Otherwise
> >> looks good to me.
> >
> >
> > Right, but I had already submitted the patch which takes care of that, and you have reviewed it too IIRC :)
>
> Ahh, I assumed this patch is based on latest stable Linux-5.11-rcX.
>
> Either you can create a series with two patches OR you can squash this patch
> into your previous patch.

Fair enough, I'll come up with a new (aggregate) one.

Best regards,
Vitaly