sravan/system76-coreboot
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

cpu/x86: Set up a separate stack for APs

Browse Source 
APs use a lot less stack, so set up a separate stack for those in .bss.

Now that CPU_INFO_V2 is the only code path that is used, there is no
need to align stacks in c_start.S.

Change-Id: I7a681a2e3003da0400843daa5d6d6180d952abf5
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/69123
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Werner Zeh <werner.zeh@siemens.com>
This commit is contained in:
Arthur Heymans
2022-11-01 23:57:24 +01:00
committed by Felix Held
parent 96b49b5acb
commit 4d75dbd1c1
3 changed files with 14 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files

8
src/arch/x86/c_start.S
View File

@@ -10,11 +10,9 @@
.global _estack .global _estack
.global _stack_size .global _stack_size
/* Stack alignment is not enforced with rmodule loader, reserve one .align 16
* extra CPU such that alignment can be enforced on entry. */
.align CONFIG_STACK_SIZE
_stack: _stack:
.space (CONFIG_MAX_CPUS+1)*CONFIG_STACK_SIZE .space CONFIG_STACK_SIZE
_estack: _estack:
.set _stack_size, _estack - _stack .set _stack_size, _estack - _stack
@@ -75,7 +73,7 @@ _start:
/* Set new stack with enforced alignment. */ /* Set new stack with enforced alignment. */
movl $_estack, %esp movl $_estack, %esp
andl $(~(CONFIG_STACK_SIZE-1)), %esp andl $(0xfffffff0), %esp
/* /*
* Now we are finished. Memory is up, data is copied and * Now we are finished. Memory is up, data is copied and

7
src/cpu/x86/Kconfig
View File

@@ -202,4 +202,11 @@ config RESERVE_MTRRS_FOR_OS
However, modern OSes use PAT to control cacheability instead of However, modern OSes use PAT to control cacheability instead of
using MTRRs. using MTRRs.
config AP_STACK_SIZE
hex
default 0x800
help
This is the amount of stack each AP needs. The BSP stack size can be
larger and is set with STACK_SIZE.
endif # ARCH_X86 endif # ARCH_X86

6
src/cpu/x86/mp_init.c
View File

@@ -215,6 +215,8 @@ static asmlinkage void ap_init(unsigned int index)
park_this_cpu(NULL); park_this_cpu(NULL);
} }
static __aligned(16) uint8_t ap_stack[CONFIG_AP_STACK_SIZE * CONFIG_MAX_CPUS];
static void setup_default_sipi_vector_params(struct sipi_params *sp) static void setup_default_sipi_vector_params(struct sipi_params *sp)
{ {
sp->gdt = (uintptr_t)&gdt; sp->gdt = (uintptr_t)&gdt;
@@ -222,8 +224,8 @@ static void setup_default_sipi_vector_params(struct sipi_params *sp)
sp->idt_ptr = (uintptr_t)&idtarg; sp->idt_ptr = (uintptr_t)&idtarg;
sp->per_cpu_segment_descriptors = (uintptr_t)&per_cpu_segment_descriptors; sp->per_cpu_segment_descriptors = (uintptr_t)&per_cpu_segment_descriptors;
sp->per_cpu_segment_selector = per_cpu_segment_selector; sp->per_cpu_segment_selector = per_cpu_segment_selector;
sp->stack_size = CONFIG_STACK_SIZE; sp->stack_size = CONFIG_AP_STACK_SIZE;
sp->stack_top = ALIGN_DOWN((uintptr_t)&_estack, CONFIG_STACK_SIZE); sp->stack_top = (uintptr_t)ap_stack + ARRAY_SIZE(ap_stack);
} }
static const unsigned int fixed_mtrrs[NUM_FIXED_MTRRS] = { static const unsigned int fixed_mtrrs[NUM_FIXED_MTRRS] = {