[PATCH v2 09/24] ARM: at91: pm: add support for waiting MCK1..4

From: Claudiu Beznea
Date: Fri Apr 09 2021 - 07:16:26 EST


SAMA7G5 has 5 master clocks 0..4. MCK0 is controlled differently than
MCK 1..4. MCK 1..4 should also be saved/restored in the last phase of
suspend/resume. Thus, adapt wait_mckrdy to support also MCK1..4.

Signed-off-by: Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx>
---
arch/arm/mach-at91/pm_suspend.S | 48 ++++++++++++++++++++++++---------
1 file changed, 35 insertions(+), 13 deletions(-)

diff --git a/arch/arm/mach-at91/pm_suspend.S b/arch/arm/mach-at91/pm_suspend.S
index 1f63bbfad728..7669b32d5257 100644
--- a/arch/arm/mach-at91/pm_suspend.S
+++ b/arch/arm/mach-at91/pm_suspend.S
@@ -22,11 +22,23 @@ tmp3 .req r6

/*
* Wait until master clock is ready (after switching master clock source)
+ *
+ * @r_mckid: register holding master clock identifier
+ *
+ * Side effects: overwrites r7, r8
*/
- .macro wait_mckrdy
-1: ldr tmp1, [pmc, #AT91_PMC_SR]
- tst tmp1, #AT91_PMC_MCKRDY
- beq 1b
+ .macro wait_mckrdy r_mckid
+#ifdef CONFIG_SOC_SAMA7
+ cmp \r_mckid, #0
+ beq 1f
+ mov r7, #AT91_PMC_MCKXRDY
+ b 2f
+#endif
+1: mov r7, #AT91_PMC_MCKRDY
+2: ldr r8, [pmc, #AT91_PMC_SR]
+ and r8, r7
+ cmp r8, r7
+ bne 2b
.endm

/*
@@ -231,7 +243,9 @@ sr_dis_exit:
bic tmp1, tmp1, #AT91_PMC_PRES
orr tmp1, tmp1, #AT91_PMC_PRES_64
str tmp1, [pmc, tmp3]
- wait_mckrdy
+
+ mov tmp3, #0
+ wait_mckrdy tmp3
b 1f

0:
@@ -267,10 +281,13 @@ sr_dis_exit:
bne 5f

/* Set lowest prescaler for fast resume. */
+ ldr tmp3, .mckr_offset
ldr tmp1, [pmc, tmp3]
bic tmp1, tmp1, #AT91_PMC_PRES
str tmp1, [pmc, tmp3]
- wait_mckrdy
+
+ mov tmp3, #0
+ wait_mckrdy tmp3
b 6f

5: /* Restore RC oscillator state */
@@ -307,6 +324,7 @@ sr_dis_exit:
.macro at91_pm_ulp1_mode
ldr pmc, .pmc_base
ldr tmp2, .mckr_offset
+ mov tmp3, #0

/* Save RC oscillator state and check if it is enabled. */
ldr tmp1, [pmc, #AT91_PMC_SR]
@@ -348,7 +366,7 @@ sr_dis_exit:
orr tmp1, tmp1, #AT91_PMC_CSS_MAIN
str tmp1, [pmc, tmp2]

- wait_mckrdy
+ wait_mckrdy tmp3

/* Enter the ULP1 mode by set WAITMODE bit in CKGR_MOR */
ldr tmp1, [pmc, #AT91_CKGR_MOR]
@@ -361,7 +379,7 @@ sr_dis_exit:
nop
nop

- wait_mckrdy
+ wait_mckrdy tmp3

/* Enable the crystal oscillator */
ldr tmp1, [pmc, #AT91_CKGR_MOR]
@@ -377,7 +395,7 @@ sr_dis_exit:
bic tmp1, tmp1, #AT91_PMC_CSS
str tmp1, [pmc, tmp2]

- wait_mckrdy
+ wait_mckrdy tmp3

/* Switch main clock source to crystal oscillator */
ldr tmp1, [pmc, #AT91_CKGR_MOR]
@@ -394,7 +412,7 @@ sr_dis_exit:
orr tmp1, tmp1, #AT91_PMC_CSS_MAIN
str tmp1, [pmc, tmp2]

- wait_mckrdy
+ wait_mckrdy tmp3

/* Restore RC oscillator state */
ldr tmp1, .saved_osc_status
@@ -573,10 +591,12 @@ sr_dis_exit:
save_mck:
str tmp1, [pmc, tmp2]

- wait_mckrdy
+ mov tmp3, #0
+ wait_mckrdy tmp3

at91_plla_disable

+ ldr tmp3, .pm_mode
cmp tmp3, #AT91_PM_ULP1
beq ulp1_mode

@@ -599,7 +619,8 @@ ulp_exit:
ldr tmp2, .saved_mckr
str tmp2, [pmc, tmp1]

- wait_mckrdy
+ mov tmp3, #0
+ wait_mckrdy tmp3

.endm

@@ -611,7 +632,8 @@ ulp_exit:
bic tmp1, tmp1, #AT91_PMC_CSS
str tmp1, [pmc, tmp2]

- wait_mckrdy
+ mov tmp3, #0
+ wait_mckrdy tmp3

/*BUMEN*/
ldr r0, .sfrbu
--
2.25.1