From 5f41f9198f296091c6a58bc2e86af1e9f019b2a3 Mon Sep 17 00:00:00 2001 From: Marek Szyprowski Date: Tue, 28 May 2019 09:38:14 +0100 Subject: ARM: 8864/1: Add workaround for I-Cache line size mismatch between CPU cores Some big.LITTLE systems have I-Cache line size mismatch between LITTLE and big cores. This patch adds a workaround for proper I-Cache support on such systems. Without it, some class of the userspace code (typically self-modifying) might suffer from random SIGILL failures. Similar workaround already exists for ARM64 architecture. I has been added by commit 116c81f427ff ("arm64: Work around systems with mismatched cache line sizes"). Signed-off-by: Marek Szyprowski Signed-off-by: Russell King --- arch/arm/mm/init.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'arch/arm/mm/init.c') diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c index be0b42937888..1a66af5bd259 100644 --- a/arch/arm/mm/init.c +++ b/arch/arm/mm/init.c @@ -242,6 +242,22 @@ static void __init arm_initrd_init(void) #endif } +#ifdef CONFIG_CPU_ICACHE_MISMATCH_WORKAROUND +void check_cpu_icache_size(int cpuid) +{ + u32 size, ctr; + + asm("mrc p15, 0, %0, c0, c0, 1" : "=r" (ctr)); + + size = 1 << ((ctr & 0xf) + 2); + if (cpuid != 0 && icache_size != size) + pr_info("CPU%u: detected I-Cache line size mismatch, workaround enabled\n", + cpuid); + if (icache_size > size) + icache_size = size; +} +#endif + void __init arm_memblock_init(const struct machine_desc *mdesc) { /* Register the kernel text, kernel data and initrd with memblock. */ -- cgit v1.2.3 From e6c4375f7c9293ffa65469d16f8ebd2586cb03f2 Mon Sep 17 00:00:00 2001 From: YueHaibing Date: Tue, 4 Jun 2019 07:19:57 +0100 Subject: ARM: 8865/1: mm: remove unused variables Fix gcc warnings: arch/arm/mm/init.c: In function 'mem_init': arch/arm/mm/init.c:456:13: warning: unused variable 'itcm_end' [-Wunused-variable] extern u32 itcm_end; ^ arch/arm/mm/init.c:455:13: warning: unused variable 'dtcm_end' [-Wunused-variable] extern u32 dtcm_end; ^ They are not used any more since commit 1c31d4e96b8c ("ARM: 8820/1: mm: Stop printing the virtual memory layout") Link: https://lkml.org/lkml/2019/5/12/82 Signed-off-by: YueHaibing Reviewed-by: Geert Uytterhoeven Reviewed-by: Krzysztof Kozlowski Signed-off-by: Russell King --- arch/arm/mm/init.c | 6 ------ 1 file changed, 6 deletions(-) (limited to 'arch/arm/mm/init.c') diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c index 1a66af5bd259..581c6ffc3056 100644 --- a/arch/arm/mm/init.c +++ b/arch/arm/mm/init.c @@ -466,12 +466,6 @@ static void __init free_highpages(void) */ void __init mem_init(void) { -#ifdef CONFIG_HAVE_TCM - /* These pointers are filled in on TCM detection */ - extern u32 dtcm_end; - extern u32 itcm_end; -#endif - set_max_mapnr(pfn_to_page(max_pfn) - mem_map); /* this will put all unused low memory onto the freelists */ -- cgit v1.2.3