* [PATCH] ARM: LPAE: Check the CPU support for the long descriptor format
@ 2012-01-04 17:04 Catalin Marinas
2012-01-04 19:34 ` Nicolas Pitre
0 siblings, 1 reply; 2+ messages in thread
From: Catalin Marinas @ 2012-01-04 17:04 UTC (permalink / raw)
To: linux-arm-kernel
This patch adds a check for the presence of the LPAE feature during the
CPU initialisation. If not present, it reports an error when
CONFIG_DEBUG_LL is enabled.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
---
arch/arm/kernel/head.S | 8 ++++++++
1 files changed, 8 insertions(+), 0 deletions(-)
diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index 54fa641..b26291c 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S
@@ -99,6 +99,14 @@ ENTRY(stext)
THUMB( it eq ) @ force fixup-able long branch encoding
beq __error_p @ yes, error 'p'
+#ifdef CONFIG_ARM_LPAE
+ mrc p15, 0, r3, c0, c1, 4 @ read ID_MMFR0
+ and r3, r3, #0xf @ extract VMSA support
+ cmp r3, #5 @ long-descriptor translation table format?
+ THUMB( it lo ) @ force fixup-able long branch encoding
+ blo __error_p @ only classic page table format
+#endif
+
#ifndef CONFIG_XIP_KERNEL
adr r3, 2f
ldmia r3, {r4, r8}
^ permalink raw reply related [flat|nested] 2+ messages in thread
* [PATCH] ARM: LPAE: Check the CPU support for the long descriptor format
2012-01-04 17:04 [PATCH] ARM: LPAE: Check the CPU support for the long descriptor format Catalin Marinas
@ 2012-01-04 19:34 ` Nicolas Pitre
0 siblings, 0 replies; 2+ messages in thread
From: Nicolas Pitre @ 2012-01-04 19:34 UTC (permalink / raw)
To: linux-arm-kernel
On Wed, 4 Jan 2012, Catalin Marinas wrote:
> This patch adds a check for the presence of the LPAE feature during the
> CPU initialisation. If not present, it reports an error when
> CONFIG_DEBUG_LL is enabled.
>
> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
> ---
> arch/arm/kernel/head.S | 8 ++++++++
> 1 files changed, 8 insertions(+), 0 deletions(-)
>
> diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
> index 54fa641..b26291c 100644
> --- a/arch/arm/kernel/head.S
> +++ b/arch/arm/kernel/head.S
> @@ -99,6 +99,14 @@ ENTRY(stext)
> THUMB( it eq ) @ force fixup-able long branch encoding
> beq __error_p @ yes, error 'p'
>
> +#ifdef CONFIG_ARM_LPAE
> + mrc p15, 0, r3, c0, c1, 4 @ read ID_MMFR0
> + and r3, r3, #0xf @ extract VMSA support
> + cmp r3, #5 @ long-descriptor translation table format?
> + THUMB( it lo ) @ force fixup-able long branch encoding
> + blo __error_p @ only classic page table format
> +#endif
> +
> #ifndef CONFIG_XIP_KERNEL
> adr r3, 2f
> ldmia r3, {r4, r8}
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>
^ permalink raw reply [flat|nested] 2+ messages in thread
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2012-01-04 17:04 [PATCH] ARM: LPAE: Check the CPU support for the long descriptor format Catalin Marinas
2012-01-04 19:34 ` Nicolas Pitre
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