[PATCH 14/24] ARM: at91: pm: add support for 2.5V LDO regulator control

Claudiu Beznea
2021-03-31T11:01:13Z

Add support to disable/enable 2.5V LDO regulator when entering/exiting
any ULP mode.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
arch/arm/mach-at91/pm.h | 1 +
arch/arm/mach-at91/pm_suspend.S | 29 +++++++++++++++++++++++++++++
2 files changed, 30 insertions(+)

diff --git a/arch/arm/mach-at91/pm.h b/arch/arm/mach-at91/pm.h
index 666474088d55..53bdc9000e44 100644
--- a/arch/arm/mach-at91/pm.h
+++ b/arch/arm/mach-at91/pm.h
@@ -13,6 +13,7 @@
#include <soc/at91/at91sam9_ddrsdr.h>
#include <soc/at91/at91sam9_sdramc.h>
#include <soc/at91/sama7-ddr.h>
+#include <soc/at91/sama7-sfrbu.h>

#define AT91_MEMCTRL_MC 0
#define AT91_MEMCTRL_SDRAMC 1
diff --git a/arch/arm/mach-at91/pm_suspend.S b/arch/arm/mach-at91/pm_suspend.S
index 8b0b8619ee8a..9c9e08fd8300 100644
--- a/arch/arm/mach-at91/pm_suspend.S
+++ b/arch/arm/mach-at91/pm_suspend.S
@@ -83,6 +83,29 @@ tmp3 .req r6

.endm

+/**
+ * Set state for 2.5V low power regulator
+ * @ena: 0 - disable regulator
+ * 1 - enable regulator
+ *
+ * Side effects: overwrites r7, r8, r9, r10
+ */
+ .macro at91_2_5V_reg_set_low_power ena
+#ifdef CONFIG_SOC_SAMA7
+ ldr r7, .sfrbu
+ mov r8, #\ena
+ ldr r9, [r7, #AT91_SFRBU_25LDOCR]
+ orr r9, r9, #AT91_SFRBU_25LDOCR_LP
+ cmp r8, #1
+ beq lp_done_\ena
+ bic r9, r9, #AT91_SFRBU_25LDOCR_LP
+lp_done_\ena:
+ ldr r10, =AT91_SFRBU_25LDOCR_LDOANAKEY
+ orr r9, r9, r10
+ str r9, [r7, #AT91_SFRBU_25LDOCR]
+#endif
+ .endm
+
.text

.arm
@@ -906,6 +929,9 @@ save_mck:

at91_plla_disable

+ /* Enable low power mode for 2.5V regulator. */
+ at91_2_5V_reg_set_low_power 1
+
ldr tmp3, .pm_mode
cmp tmp3, #AT91_PM_ULP1
beq ulp1_mode
@@ -918,6 +944,9 @@ ulp1_mode:
b ulp_exit

ulp_exit:
+ /* Disable low power mode for 2.5V regulator. */
+ at91_2_5V_reg_set_low_power 0
+
ldr pmc, .pmc_base

at91_plla_enable
--
2.25.1