ARM: sunxi: Document registers in PSCI code
The PSCI CPU_ON code accesses quite a few registers. Document
their names to make it easier to cross reference.
Also explain "lock cpu" and "unlock cpu" as enabling/disabling
debug access.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
diff --git a/arch/arm/cpu/armv7/sunxi/psci.S b/arch/arm/cpu/armv7/sunxi/psci.S
index 7ec0500..bbfeec8 100644
--- a/arch/arm/cpu/armv7/sunxi/psci.S
+++ b/arch/arm/cpu/armv7/sunxi/psci.S
@@ -165,12 +165,12 @@
str r6, [r5] @ Reset CPU
@ l1 invalidate
- ldr r6, [r0, #0x184]
+ ldr r6, [r0, #0x184] @ CPUCFG_GEN_CTRL_REG
bic r6, r6, r4
str r6, [r0, #0x184]
- @ Lock CPU
- ldr r6, [r0, #0x1e4]
+ @ Lock CPU (Disable external debug access)
+ ldr r6, [r0, #0x1e4] @ CPUCFG_DBG_CTL1_REG
bic r6, r6, r4
str r6, [r0, #0x1e4]
@@ -178,13 +178,13 @@
movw r6, #0x1ff
movt r6, #0
1: lsrs r6, r6, #1
- str r6, [r0, #0x1b0]
+ str r6, [r0, #0x1b0] @ CPU1_PWR_CLAMP
bne 1b
timer_wait r1, TEN_MS
@ Clear power gating
- ldr r6, [r0, #0x1b4]
+ ldr r6, [r0, #0x1b4] @ CPU1_PWROFF_REG
bic r6, r6, #1
str r6, [r0, #0x1b4]
@@ -192,8 +192,8 @@
mov r6, #3
str r6, [r5]
- @ Unlock CPU
- ldr r6, [r0, #0x1e4]
+ @ Unlock CPU (Enable external debug access)
+ ldr r6, [r0, #0x1e4] @ CPUCFG_DBG_CTL1_REG
orr r6, r6, r4
str r6, [r0, #0x1e4]