diff options
| author | Vladimir Serbinenko <phcoder@gmail.com> | 2013-11-26 17:49:29 +0100 |
|---|---|---|
| committer | Stefan Reinauer <stefan.reinauer@coreboot.org> | 2013-12-02 20:10:38 +0100 |
| commit | a6c29fe6841ad5e03ddb35803943bed3bc83dfd2 (patch) | |
| tree | 8d1250b77c57e4e0020cb2b027e8c395e0fa462b /src | |
| parent | 77a5abe78052ac8f65c005272700d82c2b014da7 (diff) | |
amd/car/post_cache_as_ram: Switch stack in assembly rather than in C
Compiler may do loads of optimisations around stack switch and so it's allowed
to break stack switch as it sees fit. Do it in assembly instead.
Not tested.
Change-Id: I277a62a9052e8fe9b04e7c65d149e087282ac2a2
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-on: http://review.coreboot.org/4286
Tested-by: build bot (Jenkins)
Reviewed-by: Zheng Bao <zheng.bao@amd.com>
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Diffstat (limited to 'src')
| -rw-r--r-- | src/cpu/amd/car/cache_as_ram.inc | 12 | ||||
| -rw-r--r-- | src/cpu/amd/car/post_cache_as_ram.c | 25 |
2 files changed, 22 insertions, 15 deletions
diff --git a/src/cpu/amd/car/cache_as_ram.inc b/src/cpu/amd/car/cache_as_ram.inc index 7070cf9b10..8f0abce1a5 100644 --- a/src/cpu/amd/car/cache_as_ram.inc +++ b/src/cpu/amd/car/cache_as_ram.inc @@ -414,10 +414,22 @@ CAR_FAM10_ap_out: pushl %ebx /* Init detected. */ pushl %eax /* BIST */ call cache_as_ram_main + /* We will not go back. */ post_code(0xaf) /* Should never see this POST code. */ + .globl cache_as_ram_switch_stack + +cache_as_ram_switch_stack: + /* Return address. */ + popl %eax + /* Resume memory. */ + popl %eax + subl $(( (CONFIG_DCACHE_RAM_BASE + CONFIG_DCACHE_RAM_SIZE)- (CONFIG_RAMTOP) )), %esp + pushl %eax + call cache_as_ram_new_stack + all_mtrr_msrs: /* fixed MTRR MSRs */ .long MTRRfix64K_00000_MSR diff --git a/src/cpu/amd/car/post_cache_as_ram.c b/src/cpu/amd/car/post_cache_as_ram.c index eca7673df3..3fe496e44c 100644 --- a/src/cpu/amd/car/post_cache_as_ram.c +++ b/src/cpu/amd/car/post_cache_as_ram.c @@ -75,11 +75,11 @@ static void vErrata343(void) #endif } +void cache_as_ram_switch_stack(void *resume_backup_memory); + static void post_cache_as_ram(void) { -#if CONFIG_HAVE_ACPI_RESUME - void *resume_backup_memory; -#endif + void *resume_backup_memory = NULL; #if 1 { /* Check value of esp to verify if we have enough room for stack in Cache as RAM */ @@ -92,9 +92,6 @@ static void post_cache_as_ram(void) } #endif - unsigned testx = 0x5a5a5a5a; - print_debug_pcar("testx = ", testx); - /* copy data from cache as ram to ram need to set CONFIG_RAMTOP to 2M and use var mtrr instead. */ @@ -112,21 +109,19 @@ static void post_cache_as_ram(void) vErrata343(); memcopy((void *)((CONFIG_RAMTOP)-CONFIG_DCACHE_RAM_SIZE), (void *)CONFIG_DCACHE_RAM_BASE, CONFIG_DCACHE_RAM_SIZE); //inline + cache_as_ram_switch_stack(resume_backup_memory); +} - __asm__ volatile ( - /* set new esp */ /* before CONFIG_RAMBASE */ - "subl %0, %%esp\n\t" - ::"a"( (CONFIG_DCACHE_RAM_BASE + CONFIG_DCACHE_RAM_SIZE)- (CONFIG_RAMTOP) ) - /* discard all registers (eax is used for %0), so gcc redoes everything - after the stack is moved */ - : "cc", "memory", "%ebx", "%ecx", "%edx", "%esi", "%edi", "%ebp" - ); +void +cache_as_ram_new_stack (void *resume_backup_memory); +void +cache_as_ram_new_stack (void *resume_backup_memory __attribute__ ((unused))) +{ /* We can put data to stack again */ /* only global variable sysinfo in cache need to be offset */ print_debug("Done\n"); - print_debug_pcar("testx = ", testx); print_debug("Disabling cache as ram now \n"); |