diff options
Diffstat (limited to 'src/arch/arm64')
-rw-r--r-- | src/arch/arm64/include/armv8/arch/cpu.h | 6 | ||||
-rw-r--r-- | src/arch/arm64/stage_entry.S | 79 |
2 files changed, 63 insertions, 22 deletions
diff --git a/src/arch/arm64/include/armv8/arch/cpu.h b/src/arch/arm64/include/armv8/arch/cpu.h index 70311dd194..e80e739133 100644 --- a/src/arch/arm64/include/armv8/arch/cpu.h +++ b/src/arch/arm64/include/armv8/arch/cpu.h @@ -52,4 +52,10 @@ struct cpu_info *cpu_info(void); */ unsigned int smp_processor_id(void); +/* Return the top of the stack for the specified cpu. */ +void *cpu_get_stack(unsigned int cpu); + +/* Return the top of the exception stack for the specified cpu. */ +void *cpu_get_exception_stack(unsigned int cpu); + #endif /* __ARCH_CPU_H__ */ diff --git a/src/arch/arm64/stage_entry.S b/src/arch/arm64/stage_entry.S index 2d4b26dac9..1de8894f2a 100644 --- a/src/arch/arm64/stage_entry.S +++ b/src/arch/arm64/stage_entry.S @@ -30,13 +30,58 @@ #error Need to know what ELx processor starts up in. #endif +#define STACK_SZ CONFIG_STACK_SIZE +#define EXCEPTION_STACK_SZ CONFIG_STACK_SIZE + +/* + * The stacks for each of the armv8 cores grows down from _estack. It is sized + * according to MAX_CPUS. Additionally provide exception stacks for each CPU. + */ +.section .bss, "aw", @nobits +.global _stack +.global _estack +.balign STACK_SZ +_stack: +.space CONFIG_MAX_CPUS*STACK_SZ +_estack: + +.global _stack_exceptions +.global _estack_exceptions +.balign EXCEPTION_STACK_SZ +_stack_exceptions: +.space CONFIG_MAX_CPUS*EXCEPTION_STACK_SZ +_estack_exceptions: + +ENTRY(cpu_get_stack) + mov x1, #STACK_SZ + mul x0, x0, x1 + ldr x1, 1f + sub x0, x1, x0 + ret +.align 3 +1: + .quad _estack +ENDPROC(cpu_get_stack) + +ENTRY(cpu_get_exception_stack) + mov x1, #EXCEPTION_STACK_SZ + mul x0, x0, x1 + ldr x1, 1f + sub x0, x1, x0 + ret +.align 3 +1: + .quad _estack_exceptions +ENDPROC(cpu_get_exception_stack) + + ENTRY(seed_stack) /* * Initialize the stack to a known value. This is used to check for * stack overflow later in the boot process. */ ldr x0, .stack_bottom - ldr x1, .stack_top + mov x1, sp ldr x2, =0xdeadbeefdeadbeef ldr x3, =0x8 @@ -59,36 +104,26 @@ ENDPROC(seed_stack) * stack while keeping SP_ELx reserved for exception entry. */ ENTRY(arm64_c_environment) - ldr x0, .exception_stack_top - cmp x0, #0 - b.eq 2f + bl smp_processor_id /* x0 = cpu */ + mov x24, x0 + + + /* Set the exception stack for this cpu. */ + bl cpu_get_exception_stack msr SPSel, #1 isb - mov sp, x0 - 2: /* Have stack pointer use SP_EL0. */ msr SPSel, #0 isb - /* Load up the stack if non-zero. */ - ldr x0, .stack_top - cmp x0, #0 - b.eq 1f + /* Set stack for this cpu. */ + mov x0, x24 /* x0 = cpu */ + bl cpu_get_stack mov sp, x0 - 1: - - ldr x1, .entry - br x1 - - .align 4 - .exception_stack_top: - .quad CONFIG_EXCEPTION_STACK_TOP - .stack_top: - .quad _estack - .entry: - .quad seed_stack + + b seed_stack ENDPROC(arm64_c_environment) CPU_RESET_ENTRY(arm64_cpu_startup) |