ARM: imx: add suspend/resume support for i.mx6ul
This patch adds suspend function for i.MX6UL, it supports
"standby" and "mem" mode, for "standby" mode, SoC will
enter STOP mode only, while for "mem" mode, SoC will
enter STOP mode and DDR IO will be set to low power
mode.
As i.MX6UL contains a "Cortex-A7" ARM core which has no
PL310, so we need to avoid any PL310 operations during
suspend/resume, also, we need to flush Cortex-A7's inernal
L2 cache before suspend.
Signed-off-by: Anson Huang <b20788@freescale.com>
diff --git a/arch/arm/mach-imx/suspend-imx6.S b/arch/arm/mach-imx/suspend-imx6.S
index b99987b..76ee2ce 100644
--- a/arch/arm/mach-imx/suspend-imx6.S
+++ b/arch/arm/mach-imx/suspend-imx6.S
@@ -79,12 +79,15 @@
/* sync L2 cache to drain L2's buffers to DRAM. */
#ifdef CONFIG_CACHE_L2X0
ldr r11, [r0, #PM_INFO_MX6Q_L2_V_OFFSET]
+ teq r11, #0
+ beq 6f
mov r6, #0x0
str r6, [r11, #L2X0_CACHE_SYNC]
1:
ldr r6, [r11, #L2X0_CACHE_SYNC]
ands r6, r6, #0x1
bne 1b
+6:
#endif
.endm