This allows to poke a predetermined value into a specific address upon entering the early boot code in bL_head.S.
Signed-off-by: Nicolas Pitre nico@linaro.org --- arch/arm/common/mcpm_entry.c | 12 ++++++++++++ arch/arm/common/mcpm_head.S | 16 ++++++++++++++-- arch/arm/include/asm/mcpm.h | 8 ++++++++ 3 files changed, 34 insertions(+), 2 deletions(-)
diff --git a/arch/arm/common/mcpm_entry.c b/arch/arm/common/mcpm_entry.c index 370236dd1a..4a2b32fd53 100644 --- a/arch/arm/common/mcpm_entry.c +++ b/arch/arm/common/mcpm_entry.c @@ -27,6 +27,18 @@ void mcpm_set_entry_vector(unsigned cpu, unsigned cluster, void *ptr) sync_cache_w(&mcpm_entry_vectors[cluster][cpu]); }
+extern unsigned long mcpm_entry_early_pokes[MAX_NR_CLUSTERS][MAX_CPUS_PER_CLUSTER][2]; + +void mcpm_set_early_poke(unsigned cpu, unsigned cluster, + unsigned long poke_phys_addr, unsigned long poke_val) +{ + unsigned long *poke = &mcpm_entry_early_pokes[cluster][cpu][0]; + poke[0] = poke_phys_addr; + poke[1] = poke_val; + __cpuc_flush_dcache_area((void *)poke, 8); + outer_clean_range(__pa(poke), __pa(poke + 2)); +} + static const struct mcpm_platform_ops *platform_ops;
int __init mcpm_platform_register(const struct mcpm_platform_ops *ops) diff --git a/arch/arm/common/mcpm_head.S b/arch/arm/common/mcpm_head.S index 39c96df347..49dd5352fe 100644 --- a/arch/arm/common/mcpm_head.S +++ b/arch/arm/common/mcpm_head.S @@ -71,12 +71,19 @@ ENTRY(mcpm_entry_point) * position independent way. */ adr r5, 3f - ldmia r5, {r6, r7, r8, r11} + ldmia r5, {r0, r6, r7, r8, r11} + add r0, r5, r0 @ r0 = mcpm_entry_early_pokes add r6, r5, r6 @ r6 = mcpm_entry_vectors ldr r7, [r5, r7] @ r7 = mcpm_power_up_setup_phys add r8, r5, r8 @ r8 = mcpm_sync add r11, r5, r11 @ r11 = first_man_locks
+ @ Perform an early poke, if any + add r0, r0, r4, lsl #3 + ldmia r0, {r0, r1} + teq r0, #0 + strne r1, [r0] + mov r0, #MCPM_SYNC_CLUSTER_SIZE mla r8, r0, r10, r8 @ r8 = sync cluster base
@@ -195,7 +202,8 @@ mcpm_entry_gated:
.align 2
-3: .word mcpm_entry_vectors - . +3: .word mcpm_entry_early_pokes - . + .word mcpm_entry_vectors - 3b .word mcpm_power_up_setup_phys - 3b .word mcpm_sync - 3b .word first_man_locks - 3b @@ -214,6 +222,10 @@ first_man_locks: ENTRY(mcpm_entry_vectors) .space 4 * MAX_NR_CLUSTERS * MAX_CPUS_PER_CLUSTER
+ .type mcpm_entry_early_pokes, #object +ENTRY(mcpm_entry_early_pokes) + .space 8 * MAX_NR_CLUSTERS * MAX_CPUS_PER_CLUSTER + .type mcpm_power_up_setup_phys, #object ENTRY(mcpm_power_up_setup_phys) .space 4 @ set by mcpm_sync_init() diff --git a/arch/arm/include/asm/mcpm.h b/arch/arm/include/asm/mcpm.h index 0f7b7620e9..7626a7fd49 100644 --- a/arch/arm/include/asm/mcpm.h +++ b/arch/arm/include/asm/mcpm.h @@ -42,6 +42,14 @@ extern void mcpm_entry_point(void); void mcpm_set_entry_vector(unsigned cpu, unsigned cluster, void *ptr);
/* + * This sets an early poke i.e a value to be poked into some address + * from very early assembly code before the CPU is ungated. The + * address must be physical, and if 0 then nothing will happen. + */ +void mcpm_set_early_poke(unsigned cpu, unsigned cluster, + unsigned long poke_phys_addr, unsigned long poke_val); + +/* * CPU/cluster power operations API for higher subsystems to use. */