mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-10-05 16:37:50 +00:00
Code Issues Releases Wiki Activity

ARM: mcpm: add a simple poke mechanism to the early entry code

Browse source 
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>
This commit is contained in:
Nicolas Pitre 2012-11-27 23:11:20 -05:00
parent 5135d875e1
commit de885d147a
3 changed files with 34 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

12
arch/arm/common/mcpm_entry.c
View file

@ -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)

16
arch/arm/common/mcpm_head.S
View file

@ -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()

8
arch/arm/include/asm/mcpm.h
View file

@ -41,6 +41,14 @@ 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.
*/