arm/imx6q: add suspend/resume support
It adds suspend/resume support for imx6q.
Signed-off-by: Anson Huang <b20788@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
diff --git a/arch/arm/mach-imx/Makefile b/arch/arm/mach-imx/Makefile
index 994ae82..aba7321 100644
--- a/arch/arm/mach-imx/Makefile
+++ b/arch/arm/mach-imx/Makefile
@@ -70,4 +70,4 @@
obj-$(CONFIG_SMP) += platsmp.o
obj-$(CONFIG_HOTPLUG_CPU) += hotplug.o
obj-$(CONFIG_LOCAL_TIMERS) += localtimer.o
-obj-$(CONFIG_SOC_IMX6Q) += clock-imx6q.o mach-imx6q.o
+obj-$(CONFIG_SOC_IMX6Q) += clock-imx6q.o mach-imx6q.o pm-imx6q.o
diff --git a/arch/arm/mach-imx/head-v7.S b/arch/arm/mach-imx/head-v7.S
index ede908b..6229efb 100644
--- a/arch/arm/mach-imx/head-v7.S
+++ b/arch/arm/mach-imx/head-v7.S
@@ -12,6 +12,7 @@
#include <linux/linkage.h>
#include <linux/init.h>
+#include <asm/asm-offsets.h>
#include <asm/hardware/cache-l2x0.h>
.section ".text.head", "ax"
@@ -69,3 +70,30 @@
b secondary_startup
ENDPROC(v7_secondary_startup)
#endif
+
+/*
+ * The following code is located into the .data section. This is to
+ * allow phys_l2x0_saved_regs to be accessed with a relative load
+ * as we are running on physical address here.
+ */
+ .data
+ .align
+
+ .macro pl310_resume
+ ldr r2, phys_l2x0_saved_regs
+ ldr r0, [r2, #L2X0_R_PHY_BASE] @ get physical base of l2x0
+ ldr r1, [r2, #L2X0_R_AUX_CTRL] @ get aux_ctrl value
+ str r1, [r0, #L2X0_AUX_CTRL] @ restore aux_ctrl
+ mov r1, #0x1
+ str r1, [r0, #L2X0_CTRL] @ re-enable L2
+ .endm
+
+ENTRY(v7_cpu_resume)
+ bl v7_invalidate_l1
+ pl310_resume
+ b cpu_resume
+ENDPROC(v7_cpu_resume)
+
+ .globl phys_l2x0_saved_regs
+phys_l2x0_saved_regs:
+ .long 0
diff --git a/arch/arm/mach-imx/pm-imx6q.c b/arch/arm/mach-imx/pm-imx6q.c
new file mode 100644
index 0000000..f20f191
--- /dev/null
+++ b/arch/arm/mach-imx/pm-imx6q.c
@@ -0,0 +1,70 @@
+/*
+ * Copyright 2011 Freescale Semiconductor, Inc.
+ * Copyright 2011 Linaro Ltd.
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/suspend.h>
+#include <asm/cacheflush.h>
+#include <asm/proc-fns.h>
+#include <asm/suspend.h>
+#include <asm/hardware/cache-l2x0.h>
+#include <mach/common.h>
+#include <mach/hardware.h>
+
+extern unsigned long phys_l2x0_saved_regs;
+
+static int imx6q_suspend_finish(unsigned long val)
+{
+ cpu_do_idle();
+ return 0;
+}
+
+static int imx6q_pm_enter(suspend_state_t state)
+{
+ switch (state) {
+ case PM_SUSPEND_MEM:
+ imx6q_set_lpm(STOP_POWER_OFF);
+ imx_gpc_pre_suspend();
+ imx_set_cpu_jump(0, v7_cpu_resume);
+ /* Zzz ... */
+ cpu_suspend(0, imx6q_suspend_finish);
+ imx_smp_prepare();
+ imx_gpc_post_resume();
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static const struct platform_suspend_ops imx6q_pm_ops = {
+ .enter = imx6q_pm_enter,
+ .valid = suspend_valid_only_mem,
+};
+
+void __init imx6q_pm_init(void)
+{
+ /*
+ * The l2x0 core code provides an infrastucture to save and restore
+ * l2x0 registers across suspend/resume cycle. But because imx6q
+ * retains L2 content during suspend and needs to resume L2 before
+ * MMU is enabled, it can only utilize register saving support and
+ * have to take care of restoring on its own. So we save physical
+ * address of the data structure used by l2x0 core to save registers,
+ * and later restore the necessary ones in imx6q resume entry.
+ */
+ phys_l2x0_saved_regs = __pa(&l2x0_saved_regs);
+
+ suspend_set_ops(&imx6q_pm_ops);
+}