From 6c42710ae03bd642f68220dea4dac60b6cbd6d23 Mon Sep 17 00:00:00 2001 From: Markus Pargmann Date: Tue, 8 Dec 2015 10:39:31 +0100 Subject: arm: Add RAMOOPS memory area RAMOOPS is a driver that uses a reserved static memory region to store the data from the last panic or boot. This helps to debug crashes at the next boot while preserving the boot messages. To guarantee a memory area that is not altered by barebox or the kernel, this area is located at the end of the RAM right after barebox and before the STACK. This ensures that changing barebox sizes do not interfere with RAMOOPS. Signed-off-by: Markus Pargmann Signed-off-by: Sascha Hauer --- arch/arm/cpu/start.c | 6 ++++++ arch/arm/include/asm/barebox-arm.h | 14 +++++++++++++- 2 files changed, 19 insertions(+), 1 deletion(-) diff --git a/arch/arm/cpu/start.c b/arch/arm/cpu/start.c index 4ad64b61e8..d03d1edfaf 100644 --- a/arch/arm/cpu/start.c +++ b/arch/arm/cpu/start.c @@ -118,6 +118,12 @@ static inline unsigned long arm_mem_boarddata(unsigned long membase, return mem; } +unsigned long arm_mem_ramoops_get(void) +{ + return arm_mem_ramoops(0, arm_stack_top); +} +EXPORT_SYMBOL_GPL(arm_mem_ramoops_get); + static int barebox_memory_areas_init(void) { unsigned long start = arm_head_bottom; diff --git a/arch/arm/include/asm/barebox-arm.h b/arch/arm/include/asm/barebox-arm.h index 8d52882981..67133265d1 100644 --- a/arch/arm/include/asm/barebox-arm.h +++ b/arch/arm/include/asm/barebox-arm.h @@ -122,11 +122,23 @@ static inline unsigned long arm_mem_early_malloc_end(unsigned long membase, return arm_mem_ttb(membase, endmem); } +static inline unsigned long arm_mem_ramoops(unsigned long membase, + unsigned long endmem) +{ + endmem = arm_mem_ttb(membase, endmem); +#ifdef CONFIG_FS_PSTORE_RAMOOPS + endmem -= CONFIG_FS_PSTORE_RAMOOPS_SIZE; + endmem &= ~(SZ_4K - 1); /* Align to 4K */ +#endif + + return endmem; +} + static inline unsigned long arm_mem_barebox_image(unsigned long membase, unsigned long endmem, unsigned long size) { - endmem = arm_mem_ttb(membase, endmem); + endmem = arm_mem_ramoops(membase, endmem); if (IS_ENABLED(CONFIG_RELOCATABLE)) { endmem -= size; -- cgit v1.2.3