* [PATCH] riscv: Do not invoke early_init_dt_verify() twice
@ 2021-03-24 15:03 Changbin Du
2021-03-24 15:21 ` Anup Patel
0 siblings, 1 reply; 3+ messages in thread
From: Changbin Du @ 2021-03-24 15:03 UTC (permalink / raw)
To: Paul Walmsley, Palmer Dabbelt, Albert Ou
Cc: linux-riscv, linux-kernel, Changbin Du
In the setup_arch() of riscv, function early_init_dt_verify() has
been done by parse_dtb(). So no need to call it again. Just directly
invoke unflatten_device_tree().
Signed-off-by: Changbin Du <changbin.du@gmail.com>
---
arch/riscv/kernel/setup.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)
diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
index f8f15332caa2..2a3d487e1710 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -255,10 +255,7 @@ void __init setup_arch(char **cmdline_p)
#if IS_ENABLED(CONFIG_BUILTIN_DTB)
unflatten_and_copy_device_tree();
#else
- if (early_init_dt_verify(__va(dtb_early_pa)))
- unflatten_device_tree();
- else
- pr_err("No DTB found in kernel mappings\n");
+ unflatten_device_tree();
#endif
misc_mem_init();
--
2.30.2
^ permalink raw reply related [flat|nested] 3+ messages in thread* Re: [PATCH] riscv: Do not invoke early_init_dt_verify() twice
2021-03-24 15:03 [PATCH] riscv: Do not invoke early_init_dt_verify() twice Changbin Du
@ 2021-03-24 15:21 ` Anup Patel
2021-03-25 15:55 ` Changbin Du
0 siblings, 1 reply; 3+ messages in thread
From: Anup Patel @ 2021-03-24 15:21 UTC (permalink / raw)
To: Changbin Du
Cc: Paul Walmsley, Palmer Dabbelt, Albert Ou, linux-riscv,
linux-kernel@vger.kernel.org List
On Wed, Mar 24, 2021 at 8:33 PM Changbin Du <changbin.du@gmail.com> wrote:
>
> In the setup_arch() of riscv, function early_init_dt_verify() has
> been done by parse_dtb(). So no need to call it again. Just directly
> invoke unflatten_device_tree().
>
> Signed-off-by: Changbin Du <changbin.du@gmail.com>
> ---
> arch/riscv/kernel/setup.c | 5 +----
> 1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
> index f8f15332caa2..2a3d487e1710 100644
> --- a/arch/riscv/kernel/setup.c
> +++ b/arch/riscv/kernel/setup.c
> @@ -255,10 +255,7 @@ void __init setup_arch(char **cmdline_p)
> #if IS_ENABLED(CONFIG_BUILTIN_DTB)
> unflatten_and_copy_device_tree();
> #else
> - if (early_init_dt_verify(__va(dtb_early_pa)))
> - unflatten_device_tree();
> - else
> - pr_err("No DTB found in kernel mappings\n");
> + unflatten_device_tree();
> #endif
The early_init_dt_verify() set he DTB base address in Linux OF.
When parse_dtb() calls early_init_dt_verify(), MMU is enabled but
we have temporary mapping for DTB (i.e. dtb_early_va).
After paging_init(), we have moved to final swapper_pg_dir so
temporary mapping for DTB does not exists anymore but DTB
is at same physical address so update DTB base address in
Linux OF by calling early_init_dt_verify() again.
Based on above, NACK to this patch.
Regards,
Anup
> misc_mem_init();
>
> --
> 2.30.2
>
>
> _______________________________________________
> linux-riscv mailing list
> linux-riscv@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-riscv
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [PATCH] riscv: Do not invoke early_init_dt_verify() twice
2021-03-24 15:21 ` Anup Patel
@ 2021-03-25 15:55 ` Changbin Du
0 siblings, 0 replies; 3+ messages in thread
From: Changbin Du @ 2021-03-25 15:55 UTC (permalink / raw)
To: Anup Patel
Cc: Changbin Du, Paul Walmsley, Palmer Dabbelt, Albert Ou,
linux-riscv, linux-kernel@vger.kernel.org List
On Wed, Mar 24, 2021 at 08:51:06PM +0530, Anup Patel wrote:
> On Wed, Mar 24, 2021 at 8:33 PM Changbin Du <changbin.du@gmail.com> wrote:
> >
> > In the setup_arch() of riscv, function early_init_dt_verify() has
> > been done by parse_dtb(). So no need to call it again. Just directly
> > invoke unflatten_device_tree().
> >
> > Signed-off-by: Changbin Du <changbin.du@gmail.com>
> > ---
> > arch/riscv/kernel/setup.c | 5 +----
> > 1 file changed, 1 insertion(+), 4 deletions(-)
> >
> > diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
> > index f8f15332caa2..2a3d487e1710 100644
> > --- a/arch/riscv/kernel/setup.c
> > +++ b/arch/riscv/kernel/setup.c
> > @@ -255,10 +255,7 @@ void __init setup_arch(char **cmdline_p)
> > #if IS_ENABLED(CONFIG_BUILTIN_DTB)
> > unflatten_and_copy_device_tree();
> > #else
> > - if (early_init_dt_verify(__va(dtb_early_pa)))
> > - unflatten_device_tree();
> > - else
> > - pr_err("No DTB found in kernel mappings\n");
> > + unflatten_device_tree();
> > #endif
>
> The early_init_dt_verify() set he DTB base address in Linux OF.
>
> When parse_dtb() calls early_init_dt_verify(), MMU is enabled but
> we have temporary mapping for DTB (i.e. dtb_early_va).
>
> After paging_init(), we have moved to final swapper_pg_dir so
> temporary mapping for DTB does not exists anymore but DTB
> is at same physical address so update DTB base address in
> Linux OF by calling early_init_dt_verify() again.
>
> Based on above, NACK to this patch.
>
No problem, thanks!
> Regards,
> Anup
>
> > misc_mem_init();
> >
> > --
> > 2.30.2
> >
> >
> > _______________________________________________
> > linux-riscv mailing list
> > linux-riscv@lists.infradead.org
> > http://lists.infradead.org/mailman/listinfo/linux-riscv
--
Cheers,
Changbin Du
^ permalink raw reply [flat|nested] 3+ messages in thread
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2021-03-24 15:03 [PATCH] riscv: Do not invoke early_init_dt_verify() twice Changbin Du
2021-03-24 15:21 ` Anup Patel
2021-03-25 15:55 ` Changbin Du
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