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Subject[PATCH 2/8] Revert "ARM: at91: pm: do not disable/enable PLLA for ULP modes"
Date
This reverts commit 2725d70aa5138284ba2cebf0ef51dd23e0c9ea21
("ARM: at91: pm: do not disable/enable PLLA for ULP modes").
This is because PLLA is the clock source for CPU, PLLA should
be disabled/enabled in the final/first phase of suspend/resume
so that the power consumption in suspend/resume to be minimal
and suspend/resume time to be minimized.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
arch/arm/mach-at91/pm_suspend.S | 31 +++++++++++++++++++++++++++++++
1 file changed, 31 insertions(+)

diff --git a/arch/arm/mach-at91/pm_suspend.S b/arch/arm/mach-at91/pm_suspend.S
index 52b262d56cfd..bfb3aab8859e 100644
--- a/arch/arm/mach-at91/pm_suspend.S
+++ b/arch/arm/mach-at91/pm_suspend.S
@@ -47,6 +47,15 @@ tmp2 .req r5
.endm

/*
+ * Wait until PLLA has locked.
+ */
+ .macro wait_pllalock
+1: ldr tmp1, [pmc, #AT91_PMC_SR]
+ tst tmp1, #AT91_PMC_LOCKA
+ beq 1b
+ .endm
+
+/*
* Put the processor to enter the idle state
*/
.macro at91_cpu_idle
@@ -343,6 +352,14 @@ ENTRY(at91_ulp_mode)

wait_mckrdy

+ /* Save PLLA setting and disable it */
+ ldr tmp1, [pmc, #AT91_CKGR_PLLAR]
+ str tmp1, .saved_pllar
+
+ mov tmp1, #AT91_PMC_PLLCOUNT
+ orr tmp1, tmp1, #(1 << 29) /* bit 29 always set */
+ str tmp1, [pmc, #AT91_CKGR_PLLAR]
+
ldr r0, .pm_mode
cmp r0, #AT91_PM_ULP1
beq ulp1_mode
@@ -357,6 +374,18 @@ ulp1_mode:
ulp_exit:
ldr pmc, .pmc_base

+ /* Restore PLLA setting */
+ ldr tmp1, .saved_pllar
+ str tmp1, [pmc, #AT91_CKGR_PLLAR]
+
+ tst tmp1, #(AT91_PMC_MUL & 0xff0000)
+ bne 3f
+ tst tmp1, #(AT91_PMC_MUL & ~0xff0000)
+ beq 4f
+3:
+ wait_pllalock
+4:
+
/*
* Restore master clock setting
*/
@@ -512,6 +541,8 @@ ENDPROC(at91_sramc_self_refresh)
.word 0
.saved_mckr:
.word 0
+.saved_pllar:
+ .word 0
.saved_sam9_lpr:
.word 0
.saved_sam9_lpr1:
--
2.7.4
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