From ebaeb5ae24379b5b635dc1d1fa6df904bc95b4d9 Mon Sep 17 00:00:00 2001 From: Mahesh Salgaonkar Date: Thu, 16 Feb 2012 01:14:45 +0000 Subject: fadump: Convert firmware-assisted cpu state dump data into elf notes. When registered for firmware assisted dump on powerpc, firmware preserves the registers for the active CPUs during a system crash. This patch reads the cpu register data stored in Firmware-assisted dump format (except for crashing cpu) and converts it into elf notes and updates the PT_NOTE program header accordingly. The exact register state for crashing cpu is saved to fadump crash info structure in scratch area during crash_fadump() and read during second kernel boot. Signed-off-by: Mahesh Salgaonkar Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/fadump.h | 44 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) (limited to 'arch/powerpc/include') diff --git a/arch/powerpc/include/asm/fadump.h b/arch/powerpc/include/asm/fadump.h index 9e172a5d53c7..67681958e4b8 100644 --- a/arch/powerpc/include/asm/fadump.h +++ b/arch/powerpc/include/asm/fadump.h @@ -65,6 +65,18 @@ /* Dump status flag */ #define FADUMP_ERROR_FLAG 0x2000 +#define FADUMP_CPU_ID_MASK ((1UL << 32) - 1) + +#define CPU_UNKNOWN (~((u32)0)) + +/* Utility macros */ +#define SKIP_TO_NEXT_CPU(reg_entry) \ +({ \ + while (reg_entry->reg_id != REG_ID("CPUEND")) \ + reg_entry++; \ + reg_entry++; \ +}) + /* Kernel Dump section info */ struct fadump_section { u32 request_flag; @@ -119,6 +131,9 @@ struct fw_dump { unsigned long reserve_bootvar; unsigned long fadumphdr_addr; + unsigned long cpu_notes_buf; + unsigned long cpu_notes_buf_size; + int ibm_configure_kernel_dump; unsigned long fadump_enabled:1; @@ -143,13 +158,40 @@ static inline u64 str_to_u64(const char *str) return val; } #define STR_TO_HEX(x) str_to_u64(x) +#define REG_ID(x) str_to_u64(x) #define FADUMP_CRASH_INFO_MAGIC STR_TO_HEX("FADMPINF") +#define REGSAVE_AREA_MAGIC STR_TO_HEX("REGSAVE") + +/* The firmware-assisted dump format. + * + * The register save area is an area in the partition's memory used to preserve + * the register contents (CPU state data) for the active CPUs during a firmware + * assisted dump. The dump format contains register save area header followed + * by register entries. Each list of registers for a CPU starts with + * "CPUSTRT" and ends with "CPUEND". + */ + +/* Register save area header. */ +struct fadump_reg_save_area_header { + u64 magic_number; + u32 version; + u32 num_cpu_offset; +}; + +/* Register entry. */ +struct fadump_reg_entry { + u64 reg_id; + u64 reg_value; +}; /* fadump crash info structure */ struct fadump_crash_info_header { u64 magic_number; u64 elfcorehdr_addr; + u32 crashing_cpu; + struct pt_regs regs; + struct cpumask cpu_online_mask; }; /* Crash memory ranges */ @@ -165,7 +207,9 @@ extern int early_init_dt_scan_fw_dump(unsigned long node, extern int fadump_reserve_mem(void); extern int setup_fadump(void); extern int is_fadump_active(void); +extern void crash_fadump(struct pt_regs *, const char *); #else /* CONFIG_FA_DUMP */ static inline int is_fadump_active(void) { return 0; } +static inline void crash_fadump(struct pt_regs *regs, const char *str) { } #endif #endif -- cgit v1.2.1