[U-Boot] [PATCH] ARM: cpu: Add ARMv7 barrier operations support

Albert ARIBAUD albert.u.boot at aribaud.net
Thu Apr 16 14:06:29 CEST 2015


Hello Vladimir,

On Fri, 20 Mar 2015 18:16:17 +0300, Vladimir Barinov <vladimir.barinov at cogentembedded.com> wrote:
> From: Valentine Barshak <valentine.barshak at cogentembedded.com>
> 
> This enables ARMv7 barrier operations support when
> march=armv7-a is enabled.
> 
> Using CP15 barriers causes U-Boot bootm command crash when
> transferring control to the loaded image on Renesas R8A7794 Cortex A7 CPU.
> Using ARMv7 barrier operations instead of the deprecated CP15 barriers
> helps to avoid these issues.
> 
> Signed-off-by: Valentine Barshak <valentine.barshak+renesas at cogentembedded.com>
> Signed-off-by: Vladimir Barinov <vladimir.barinov+renesas at cogentembedded.com>
> Reviewed-by: Tom Rini <trini at konsulko.com>
> ---
>  arch/arm/cpu/armv7/cache_v7.c | 14 +++++++-------
>  arch/arm/include/asm/armv7.h  | 10 ++++++++++
>  2 files changed, 17 insertions(+), 7 deletions(-)
> 
> diff --git a/arch/arm/cpu/armv7/cache_v7.c b/arch/arm/cpu/armv7/cache_v7.c
> index 0f9d837..e8ee875 100644
> --- a/arch/arm/cpu/armv7/cache_v7.c
> +++ b/arch/arm/cpu/armv7/cache_v7.c
> @@ -68,7 +68,7 @@ static void v7_inval_dcache_level_setway(u32 level, u32 num_sets,
>  		}
>  	}
>  	/* DSB to make sure the operation is complete */
> -	CP15DSB;
> +	DSB;
>  }
>  
>  static void v7_clean_inval_dcache_level_setway(u32 level, u32 num_sets,
> @@ -96,7 +96,7 @@ static void v7_clean_inval_dcache_level_setway(u32 level, u32 num_sets,
>  		}
>  	}
>  	/* DSB to make sure the operation is complete */
> -	CP15DSB;
> +	DSB;
>  }
>  
>  static void v7_maint_dcache_level_setway(u32 level, u32 operation)
> @@ -215,7 +215,7 @@ static void v7_dcache_maint_range(u32 start, u32 stop, u32 range_op)
>  	}
>  
>  	/* DSB to make sure the operation is complete */
> -	CP15DSB;
> +	DSB;
>  }
>  
>  /* Invalidate TLB */
> @@ -228,9 +228,9 @@ static void v7_inval_tlb(void)
>  	/* Invalidate entire instruction TLB */
>  	asm volatile ("mcr p15, 0, %0, c8, c5, 0" : : "r" (0));
>  	/* Full system DSB - make sure that the invalidation is complete */
> -	CP15DSB;
> +	DSB;
>  	/* Full system ISB - make sure the instruction stream sees it */
> -	CP15ISB;
> +	ISB;
>  }
>  
>  void invalidate_dcache_all(void)
> @@ -343,10 +343,10 @@ void invalidate_icache_all(void)
>  	asm volatile ("mcr p15, 0, %0, c7, c5, 6" : : "r" (0));
>  
>  	/* Full system DSB - make sure that the invalidation is complete */
> -	CP15DSB;
> +	DSB;
>  
>  	/* ISB - make sure the instruction stream sees it */
> -	CP15ISB;
> +	ISB;
>  }
>  #else
>  void invalidate_icache_all(void)
> diff --git a/arch/arm/include/asm/armv7.h b/arch/arm/include/asm/armv7.h
> index a13da23..189f3f0 100644
> --- a/arch/arm/include/asm/armv7.h
> +++ b/arch/arm/include/asm/armv7.h
> @@ -70,6 +70,16 @@
>  #define CP15DSB	asm volatile ("mcr     p15, 0, %0, c7, c10, 4" : : "r" (0))
>  #define CP15DMB	asm volatile ("mcr     p15, 0, %0, c7, c10, 5" : : "r" (0))
>  
> +#ifdef __ARM_ARCH_7A__
> +#define ISB	asm volatile ("isb" : : : "memory")
> +#define DSB	asm volatile ("dsb" : : : "memory")
> +#define DMB	asm volatile ("dmb" : : : "memory")
> +#else
> +#define ISB	CP15ISB
> +#define DSB	CP15DSB
> +#define DMB	CP15DMB
> +#endif
> +
>  /*
>   * Workaround for ARM errata # 798870
>   * Set L2ACTLR[7] to reissue any memory transaction in the L2 that has been
> -- 
> 1.9.3
> 

Applied to u-boot-arm/master, thanks!

Amicalement,
-- 
Albert.


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