Commit 087bb28329f3ccda4e50cb4cf297542d7e773e20
1 parent
0e574461c4
Exists in
smarc-l5.0.0_1.0.0-ga
and in
5 other branches
ARM: imx: replicate the diagnostic register of boot cpu into secondary cores
The diagnostic register holds the errata bits. Mostly bootloader does not bring up secondary cores, so that when errata bits are set in bootloader, they are set only for boot cpu. But on a SMP configuration, it should be equally done on every single core. Set up the diagnostic register for secondary cores by replicating the register from boot cpu. Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Acked-by: Dirk Behme <dirk.behme@de.bosch.com>
Showing 2 changed files with 26 additions and 0 deletions Side-by-side Diff
arch/arm/mach-imx/headsmp.S
| ... | ... | @@ -18,8 +18,20 @@ |
| 18 | 18 | .section ".text.head", "ax" |
| 19 | 19 | |
| 20 | 20 | #ifdef CONFIG_SMP |
| 21 | +diag_reg_offset: | |
| 22 | + .word g_diag_reg - . | |
| 23 | + | |
| 24 | + .macro set_diag_reg | |
| 25 | + adr r0, diag_reg_offset | |
| 26 | + ldr r1, [r0] | |
| 27 | + add r1, r1, r0 @ r1 = physical &g_diag_reg | |
| 28 | + ldr r0, [r1] | |
| 29 | + mcr p15, 0, r0, c15, c0, 1 @ write diagnostic register | |
| 30 | + .endm | |
| 31 | + | |
| 21 | 32 | ENTRY(v7_secondary_startup) |
| 22 | 33 | bl v7_invalidate_l1 |
| 34 | + set_diag_reg | |
| 23 | 35 | b secondary_startup |
| 24 | 36 | ENDPROC(v7_secondary_startup) |
| 25 | 37 | #endif |
arch/arm/mach-imx/platsmp.c
| ... | ... | @@ -12,6 +12,7 @@ |
| 12 | 12 | |
| 13 | 13 | #include <linux/init.h> |
| 14 | 14 | #include <linux/smp.h> |
| 15 | +#include <asm/cacheflush.h> | |
| 15 | 16 | #include <asm/page.h> |
| 16 | 17 | #include <asm/smp_scu.h> |
| 17 | 18 | #include <asm/mach/map.h> |
| ... | ... | @@ -21,6 +22,7 @@ |
| 21 | 22 | |
| 22 | 23 | #define SCU_STANDBY_ENABLE (1 << 5) |
| 23 | 24 | |
| 25 | +u32 g_diag_reg; | |
| 24 | 26 | static void __iomem *scu_base; |
| 25 | 27 | |
| 26 | 28 | static struct map_desc scu_io_desc __initdata = { |
| ... | ... | @@ -80,6 +82,18 @@ |
| 80 | 82 | static void __init imx_smp_prepare_cpus(unsigned int max_cpus) |
| 81 | 83 | { |
| 82 | 84 | imx_smp_prepare(); |
| 85 | + | |
| 86 | + /* | |
| 87 | + * The diagnostic register holds the errata bits. Mostly bootloader | |
| 88 | + * does not bring up secondary cores, so that when errata bits are set | |
| 89 | + * in bootloader, they are set only for boot cpu. But on a SMP | |
| 90 | + * configuration, it should be equally done on every single core. | |
| 91 | + * Read the register from boot cpu here, and will replicate it into | |
| 92 | + * secondary cores when booting them. | |
| 93 | + */ | |
| 94 | + asm("mrc p15, 0, %0, c15, c0, 1" : "=r" (g_diag_reg) : : "cc"); | |
| 95 | + __cpuc_flush_dcache_area(&g_diag_reg, sizeof(g_diag_reg)); | |
| 96 | + outer_clean_range(__pa(&g_diag_reg), __pa(&g_diag_reg + 1)); | |
| 83 | 97 | } |
| 84 | 98 | |
| 85 | 99 | struct smp_operations imx_smp_ops __initdata = { |