[PATCH v4 7/7] arm/imx6q: add suspend/resume support
Shawn Guo
shawn.guo at linaro.org
Wed Sep 28 05:06:48 EDT 2011
It adds suspend/resume support for imx6q.
Signed-off-by: Anson Huang <b20788 at freescale.com>
Signed-off-by: Shawn Guo <shawn.guo at linaro.org>
---
arch/arm/mach-imx/Makefile | 2 +-
arch/arm/mach-imx/head-v7.S | 32 +++++++++++
arch/arm/mach-imx/pm-imx6q.c | 90 +++++++++++++++++++++++++++++++
arch/arm/plat-mxc/include/mach/common.h | 9 +++
4 files changed, 132 insertions(+), 1 deletions(-)
create mode 100644 arch/arm/mach-imx/pm-imx6q.c
diff --git a/arch/arm/mach-imx/Makefile b/arch/arm/mach-imx/Makefile
index 31c8602..e6c36b4 100644
--- a/arch/arm/mach-imx/Makefile
+++ b/arch/arm/mach-imx/Makefile
@@ -71,4 +71,4 @@ AFLAGS_head-v7.o :=-Wa,-march=armv7-a
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..1f6316c 100644
--- a/arch/arm/mach-imx/head-v7.S
+++ b/arch/arm/mach-imx/head-v7.S
@@ -69,3 +69,35 @@ ENTRY(v7_secondary_startup)
b secondary_startup
ENDPROC(v7_secondary_startup)
#endif
+
+ENTRY(pl310_get_save_ptr)
+ ldr r0, =pl310_pbase
+ mov pc, lr
+ENDPROC(pl310_get_save_ptr)
+
+/*
+ * The following code is located into the .data section. This is to
+ * allow pl310_pbase and pl310_aux_ctrl to be accessed with a relative
+ * load as we are running on physical address here.
+ */
+ .data
+ .align
+
+ .macro pl310_resume
+ adr r2, pl310_pbase
+ ldmia r2, {r0, r1}
+ 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)
+
+pl310_pbase:
+ .long 0
+pl310_aux_ctrl:
+ .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..db41343
--- /dev/null
+++ b/arch/arm/mach-imx/pm-imx6q.c
@@ -0,0 +1,90 @@
+/*
+ * 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>
+
+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)
+{
+ struct device_node *np;
+ u32 reg[2], *ptr;
+ void __iomem *base;
+
+ np = of_find_compatible_node(NULL, NULL, "arm,pl310-cache");
+ of_property_read_u32_array(np, "reg", reg, ARRAY_SIZE(reg));
+ base = ioremap(reg[0], reg[1]);
+ WARN_ON(!base);
+
+ /*
+ * On imx6q, during system suspend, ARM core gets powered off,
+ * but L2 cache is retained. To avoid cleaning the entire L2,
+ * we need to save L2 controller registers, and when system gets
+ * woke up, restore the registers and re-enable L2 before
+ * calling into cpu_resume().
+ *
+ * Most of pl310 configuration upon reset work just fine for
+ * imx6q, and the only one register we actually need to save is
+ * AUX_CTRL. Also since pl310 configuration won't change in a
+ * live system, we can save it here only once, and restore it
+ * every time system resumes back from v7_cpu_resume().
+ */
+ ptr = pl310_get_save_ptr();
+ /* save pl310 physical base address */
+ *ptr = reg[0];
+ /* save pl310 aux_ctrl register */
+ *(ptr + 1) = readl_relaxed(base + L2X0_AUX_CTRL);
+ /* ensure they are written into external memory */
+ __cpuc_flush_dcache_area((void *) ptr, sizeof(*ptr) * 2);
+ outer_clean_range(__pa(ptr), __pa(ptr + 2));
+
+ iounmap(base);
+
+ suspend_set_ops(&imx6q_pm_ops);
+}
diff --git a/arch/arm/plat-mxc/include/mach/common.h b/arch/arm/plat-mxc/include/mach/common.h
index 571e91d..318b995 100644
--- a/arch/arm/plat-mxc/include/mach/common.h
+++ b/arch/arm/plat-mxc/include/mach/common.h
@@ -13,6 +13,7 @@
struct platform_device;
struct clk;
+enum mxc_cpu_pwr_mode;
extern void mx1_map_io(void);
extern void mx21_map_io(void);
@@ -96,14 +97,22 @@ extern void imx_lluart_map_io(void);
#else
static inline void imx_lluart_map_io(void) {}
#endif
+extern void v7_cpu_resume(void);
+extern u32 *pl310_get_save_ptr(void);
#ifdef CONFIG_SMP
extern void v7_secondary_startup(void);
extern void imx_scu_map_io(void);
+extern void imx_smp_prepare(void);
#else
static inline void imx_scu_map_io(void) {}
+static inline void imx_smp_prepare(void) {}
#endif
extern void imx_enable_cpu(int cpu, bool enable);
extern void imx_set_cpu_jump(int cpu, void *jump_addr);
extern void imx_src_init(void);
extern void imx_gpc_init(void);
+extern void imx_gpc_pre_suspend(void);
+extern void imx_gpc_post_resume(void);
+extern int imx6q_set_lpm(enum mxc_cpu_pwr_mode mode);
+extern void imx6q_pm_init(void);
#endif
--
1.7.4.1
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