======================== high address ======================
.
.
.
^
^
^
imx6_suspend code
PM_INFO structure(imx6_cpu_pm_info)
======================== low address =======================
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Anson Huang <b20788@freescale.com>
---
Changes since V7:
Add __initconst to imx6q_mmdc_io_offset[].
arch/arm/mach-imx/Makefile | 3 +-
arch/arm/mach-imx/common.h | 8 +-
arch/arm/mach-imx/hardware.h | 4 +-
arch/arm/mach-imx/mach-imx6q.c | 2 +-
arch/arm/mach-imx/mach-imx6sl.c | 3 +-
arch/arm/mach-imx/pm-imx6q.c | 281 +++++++++++++++++++++++++++++++++++-
arch/arm/mach-imx/suspend-imx6.S | 289 ++++++++++++++++++++++++++++++++++++++
7 files changed, 579 insertions(+), 11 deletions(-)
create mode 100644 arch/arm/mach-imx/suspend-imx6.S
@@ -102,7 +102,8 @@ obj-$(CONFIG_SOC_IMX6Q) += clk-imx6q.o mach-imx6q.o
obj-$(CONFIG_SOC_IMX6SL) += clk-imx6sl.o mach-imx6sl.o
ifeq ($(CONFIG_PM),y)
-obj-$(CONFIG_SOC_IMX6Q) += pm-imx6q.o headsmp.o
+AFLAGS_suspend-imx6.o :=-Wa,-march=armv7-a
+obj-$(CONFIG_SOC_IMX6Q) += pm-imx6q.o headsmp.o suspend-imx6.o
# i.MX6SL reuses i.MX6Q code
obj-$(CONFIG_SOC_IMX6SL) += pm-imx6q.o headsmp.o
endif
@@ -1,5 +1,5 @@
/*
- * Copyright 2004-2013 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright 2004-2014 Freescale Semiconductor, Inc. All Rights Reserved.
*/
/*
@@ -145,11 +145,17 @@ void imx_cpu_die(unsigned int cpu);
int imx_cpu_kill(unsigned int cpu);
#ifdef CONFIG_PM
+void imx6_suspend(void __iomem *ocram_vbase);
void imx6q_pm_init(void);
+void imx6dl_pm_init(void);
+void imx6sl_pm_init(void);
void imx6q_pm_set_ccm_base(void __iomem *base);
void imx5_pm_init(void);
#else
+static inline void imx6_suspend(void __iomem *ocram_vbase) {}
static inline void imx6q_pm_init(void) {}
+static inline void imx6dl_pm_init(void) {}
+static inline void imx6sl_pm_init(void) {}
static inline void imx6q_pm_set_ccm_base(void __iomem *base) {}
static inline void imx5_pm_init(void) {}
#endif
@@ -1,5 +1,5 @@
/*
- * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright 2004-2007, 2014 Freescale Semiconductor, Inc. All Rights Reserved.
* Copyright 2008 Juergen Beisert, kernel@pengutronix.de
*
* This program is free software; you can redistribute it and/or
@@ -20,7 +20,9 @@
#ifndef __ASM_ARCH_MXC_HARDWARE_H__
#define __ASM_ARCH_MXC_HARDWARE_H__
+#ifndef __ASSEMBLY__
#include <asm/io.h>
+#endif
#include <asm/sizes.h>
#define addr_in_module(addr, mod) \
@@ -212,7 +212,7 @@ static void __init imx6q_init_machine(void)
of_platform_populate(NULL, of_default_bus_match_table, NULL, parent);
imx_anatop_init();
- imx6q_pm_init();
+ cpu_is_imx6q() ? imx6q_pm_init() : imx6dl_pm_init();
imx6q_1588_init();
}
@@ -55,8 +55,7 @@ static void __init imx6sl_init_machine(void)
imx6sl_fec_init();
imx_anatop_init();
- /* Reuse imx6q pm code */
- imx6q_pm_init();
+ imx6sl_pm_init();
}
static void __init imx6sl_init_irq(void)
@@ -1,5 +1,5 @@
/*
- * Copyright 2011-2013 Freescale Semiconductor, Inc.
+ * Copyright 2011-2014 Freescale Semiconductor, Inc.
* Copyright 2011 Linaro Ltd.
*
* The code contained herein is licensed under the GNU General Public
@@ -14,16 +14,19 @@
#include <linux/init.h>
#include <linux/io.h>
#include <linux/irq.h>
+#include <linux/genalloc.h>
#include <linux/mfd/syscon.h>
#include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
#include <linux/of.h>
#include <linux/of_address.h>
+#include <linux/of_platform.h>
#include <linux/regmap.h>
#include <linux/suspend.h>
#include <asm/cacheflush.h>
+#include <asm/fncpy.h>
#include <asm/proc-fns.h>
#include <asm/suspend.h>
-#include <asm/hardware/cache-l2x0.h>
+#include <asm/tlb.h>
#include "common.h"
#include "hardware.h"
@@ -58,7 +61,85 @@
#define CGPR 0x64
#define BM_CGPR_INT_MEM_CLK_LPM (0x1 << 17)
+#define MX6Q_SUSPEND_OCRAM_SIZE 0x1000
+#define MX6_MAX_MMDC_IO_NUM 33
+
static void __iomem *ccm_base;
+static void __iomem *suspend_ocram_base;
+static void (*imx6_suspend_in_ocram_fn)(void __iomem *ocram_vbase);
+
+/*
+ * suspend ocram space layout:
+ * ======================== high address ======================
+ * .
+ * .
+ * .
+ * ^
+ * ^
+ * ^
+ * imx6_suspend code
+ * PM_INFO structure(imx6_cpu_pm_info)
+ * ======================== low address =======================
+ */
+
+struct imx6_pm_base {
+ phys_addr_t pbase;
+ void __iomem *vbase;
+};
+
+struct imx6_pm_socdata {
+ u32 cpu_type;
+ const char *mmdc_compat;
+ const char *src_compat;
+ const char *iomuxc_compat;
+ const char *gpc_compat;
+ const u32 mmdc_io_num;
+ const u32 *mmdc_io_offset;
+};
+
+static const u32 imx6q_mmdc_io_offset[] __initconst = {
+ 0x5ac, 0x5b4, 0x528, 0x520, /* DQM0 ~ DQM3 */
+ 0x514, 0x510, 0x5bc, 0x5c4, /* DQM4 ~ DQM7 */
+ 0x56c, 0x578, 0x588, 0x594, /* CAS, RAS, SDCLK_0, SDCLK_1 */
+ 0x5a8, 0x5b0, 0x524, 0x51c, /* SDQS0 ~ SDQS3 */
+ 0x518, 0x50c, 0x5b8, 0x5c0, /* SDQS4 ~ SDQS7 */
+ 0x784, 0x788, 0x794, 0x79c, /* GPR_B0DS ~ GPR_B3DS */
+ 0x7a0, 0x7a4, 0x7a8, 0x748, /* GPR_B4DS ~ GPR_B7DS */
+ 0x59c, 0x5a0, 0x750, 0x774, /* SODT0, SODT1, MODE_CTL, MODE */
+ 0x74c, /* GPR_ADDS */
+};
+
+static const struct imx6_pm_socdata imx6q_pm_data __initconst = {
+ .cpu_type = MXC_CPU_IMX6Q,
+ .mmdc_compat = "fsl,imx6q-mmdc",
+ .src_compat = "fsl,imx6q-src",
+ .iomuxc_compat = "fsl,imx6q-iomuxc",
+ .gpc_compat = "fsl,imx6q-gpc",
+ .mmdc_io_num = ARRAY_SIZE(imx6q_mmdc_io_offset),
+ .mmdc_io_offset = imx6q_mmdc_io_offset,
+};
+
+/*
+ * This structure is for passing necessary data for low level ocram
+ * suspend code(arch/arm/mach-imx/suspend-imx6.S), if this struct
+ * definition is changed, the offset definition in
+ * arch/arm/mach-imx/suspend-imx6.S must be also changed accordingly,
+ * otherwise, the suspend to ocram function will be broken!
+ */
+struct imx6_cpu_pm_info {
+ phys_addr_t pbase; /* The physical address of pm_info. */
+ phys_addr_t resume_addr; /* The physical resume address for asm code */
+ u32 cpu_type;
+ u32 pm_info_size; /* Size of pm_info. */
+ struct imx6_pm_base mmdc_base;
+ struct imx6_pm_base src_base;
+ struct imx6_pm_base iomuxc_base;
+ struct imx6_pm_base ccm_base;
+ struct imx6_pm_base gpc_base;
+ struct imx6_pm_base l2_base;
+ u32 mmdc_io_num; /* Number of MMDC IOs which need saved/restored. */
+ u32 mmdc_io_val[MX6_MAX_MMDC_IO_NUM][2]; /* To save offset and value */
+} __aligned(8);
void imx6q_set_int_mem_clk_lpm(void)
{
@@ -177,7 +258,17 @@ int imx6q_set_lpm(enum mxc_cpu_pwr_mode mode)
static int imx6q_suspend_finish(unsigned long val)
{
- cpu_do_idle();
+ if (!imx6_suspend_in_ocram_fn) {
+ cpu_do_idle();
+ } else {
+ /*
+ * call low level suspend function in ocram,
+ * as we need to float DDR IO.
+ */
+ local_flush_tlb_all();
+ imx6_suspend_in_ocram_fn(suspend_ocram_base);
+ }
+
return 0;
}
@@ -187,7 +278,12 @@ static int imx6q_pm_enter(suspend_state_t state)
case PM_SUSPEND_MEM:
imx6q_set_lpm(STOP_POWER_OFF);
imx6q_enable_wb(true);
- imx6q_enable_rbc(true);
+ /*
+ * For suspend into ocram, asm code already take care of
+ * RBC setting, so we do NOT need to do that here.
+ */
+ if (!imx6_suspend_in_ocram_fn)
+ imx6q_enable_rbc(true);
imx_gpc_pre_suspend();
imx_anatop_pre_suspend();
imx_set_cpu_jump(0, v7_cpu_resume);
@@ -218,12 +314,172 @@ void __init imx6q_pm_set_ccm_base(void __iomem *base)
ccm_base = base;
}
-void __init imx6q_pm_init(void)
+static int __init imx6_pm_get_base(struct imx6_pm_base *base,
+ const char *compat)
+{
+ struct device_node *node;
+ struct resource res;
+ int ret = 0;
+
+ node = of_find_compatible_node(NULL, NULL, compat);
+ if (!node) {
+ ret = -ENODEV;
+ goto out;
+ }
+
+ ret = of_address_to_resource(node, 0, &res);
+ if (ret)
+ goto put_node;
+
+ base->pbase = res.start;
+ base->vbase = ioremap(res.start, resource_size(&res));
+ if (!base->vbase)
+ ret = -ENOMEM;
+
+put_node:
+ of_node_put(node);
+out:
+ return ret;
+}
+
+static int __init imx6q_ocram_suspend_init(const struct imx6_pm_socdata
+ *socdata)
+{
+ phys_addr_t ocram_pbase;
+ struct device_node *node;
+ struct platform_device *pdev;
+ struct imx6_cpu_pm_info *pm_info;
+ struct gen_pool *ocram_pool;
+ unsigned long ocram_base;
+ int i, ret = 0;
+ const u32 *mmdc_offset_array;
+
+ if (!socdata) {
+ pr_warn("%s: invalid argument!\n", __func__);
+ return -EINVAL;
+ }
+
+ node = of_find_compatible_node(NULL, NULL, "mmio-sram");
+ if (!node) {
+ pr_warn("%s: failed to find ocram node!\n", __func__);
+ return -ENODEV;
+ }
+
+ pdev = of_find_device_by_node(node);
+ if (!pdev) {
+ pr_warn("%s: failed to find ocram device!\n", __func__);
+ ret = -ENODEV;
+ goto put_node;
+ }
+
+ ocram_pool = dev_get_gen_pool(&pdev->dev);
+ if (!ocram_pool) {
+ pr_warn("%s: ocram pool unavailable!\n", __func__);
+ ret = -ENODEV;
+ goto put_node;
+ }
+
+ ocram_base = gen_pool_alloc(ocram_pool, MX6Q_SUSPEND_OCRAM_SIZE);
+ if (!ocram_base) {
+ pr_warn("%s: unable to alloc ocram!\n", __func__);
+ ret = -ENOMEM;
+ goto put_node;
+ }
+
+ ocram_pbase = gen_pool_virt_to_phys(ocram_pool, ocram_base);
+
+ suspend_ocram_base = __arm_ioremap_exec(ocram_pbase,
+ MX6Q_SUSPEND_OCRAM_SIZE, false);
+
+ pm_info = suspend_ocram_base;
+ pm_info->pbase = ocram_pbase;
+ pm_info->resume_addr = virt_to_phys(v7_cpu_resume);
+ pm_info->pm_info_size = sizeof(*pm_info);
+
+ /*
+ * ccm physical address is not used by asm code currently,
+ * so get ccm virtual address directly, as we already have
+ * it from ccm driver.
+ */
+ pm_info->ccm_base.vbase = ccm_base;
+
+ ret = imx6_pm_get_base(&pm_info->mmdc_base, socdata->mmdc_compat);
+ if (ret) {
+ pr_warn("%s: failed to get mmdc base %d!\n", __func__, ret);
+ goto put_node;
+ }
+
+ ret = imx6_pm_get_base(&pm_info->src_base, socdata->src_compat);
+ if (ret) {
+ pr_warn("%s: failed to get src base %d!\n", __func__, ret);
+ goto src_map_failed;
+ }
+
+ ret = imx6_pm_get_base(&pm_info->iomuxc_base, socdata->iomuxc_compat);
+ if (ret) {
+ pr_warn("%s: failed to get iomuxc base %d!\n", __func__, ret);
+ goto iomuxc_map_failed;
+ }
+
+ ret = imx6_pm_get_base(&pm_info->gpc_base, socdata->gpc_compat);
+ if (ret) {
+ pr_warn("%s: failed to get gpc base %d!\n", __func__, ret);
+ goto gpc_map_failed;
+ }
+
+ ret = imx6_pm_get_base(&pm_info->l2_base, "arm,pl310-cache");
+ if (ret) {
+ pr_warn("%s: failed to get pl310-cache base %d!\n",
+ __func__, ret);
+ goto pl310_cache_map_failed;
+ }
+
+ pm_info->cpu_type = socdata->cpu_type;
+ pm_info->mmdc_io_num = socdata->mmdc_io_num;
+ mmdc_offset_array = socdata->mmdc_io_offset;
+
+ for (i = 0; i < pm_info->mmdc_io_num; i++) {
+ pm_info->mmdc_io_val[i][0] =
+ mmdc_offset_array[i];
+ pm_info->mmdc_io_val[i][1] =
+ readl_relaxed(pm_info->iomuxc_base.vbase +
+ mmdc_offset_array[i]);
+ }
+
+ imx6_suspend_in_ocram_fn = fncpy(
+ suspend_ocram_base + sizeof(*pm_info),
+ &imx6_suspend,
+ MX6Q_SUSPEND_OCRAM_SIZE - sizeof(*pm_info));
+
+ goto put_node;
+
+pl310_cache_map_failed:
+ iounmap(&pm_info->gpc_base.vbase);
+gpc_map_failed:
+ iounmap(&pm_info->iomuxc_base.vbase);
+iomuxc_map_failed:
+ iounmap(&pm_info->src_base.vbase);
+src_map_failed:
+ iounmap(&pm_info->mmdc_base.vbase);
+put_node:
+ of_node_put(node);
+
+ return ret;
+}
+
+static void __init imx6_pm_common_init(const struct imx6_pm_socdata
+ *socdata)
{
struct regmap *gpr;
+ int ret;
WARN_ON(!ccm_base);
+ ret = imx6q_ocram_suspend_init(socdata);
+ if (ret)
+ pr_warn("%s: failed to initialize ocram suspend %d!\n",
+ __func__, ret);
+
/*
* This is for SW workaround step #1 of ERR007265, see comments
* in imx6q_set_lpm for details of this errata.
@@ -241,3 +497,18 @@ void __init imx6q_pm_init(void)
suspend_set_ops(&imx6q_pm_ops);
}
+
+void __init imx6q_pm_init(void)
+{
+ imx6_pm_common_init(&imx6q_pm_data);
+}
+
+void __init imx6dl_pm_init(void)
+{
+ imx6_pm_common_init(NULL);
+}
+
+void __init imx6sl_pm_init(void)
+{
+ imx6_pm_common_init(NULL);
+}
new file mode 100644
@@ -0,0 +1,289 @@
+/*
+ * Copyright 2014 Freescale Semiconductor, Inc.
+ *
+ * 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/linkage.h>
+#include <asm/hardware/cache-l2x0.h>
+#include "hardware.h"
+
+/*
+ * ==================== low level suspend ====================
+ *
+ * Better to follow below rules to use ARM registers:
+ * r0: pm_info structure address;
+ * r1 ~ r4: for saving pm_info members;
+ * r5 ~ r10: free registers;
+ * r11: io base address.
+ *
+ * suspend ocram space layout:
+ * ======================== high address ======================
+ * .
+ * .
+ * .
+ * ^
+ * ^
+ * ^
+ * imx6_suspend code
+ * PM_INFO structure(imx6_cpu_pm_info)
+ * ======================== low address =======================
+ */
+
+/*
+ * Below offsets are based on struct imx6_cpu_pm_info
+ * which defined in arch/arm/mach-imx/pm-imx6q.c, this
+ * structure contains necessary pm info for low level
+ * suspend related code.
+ */
+#define PM_INFO_PBASE_OFFSET 0x0
+#define PM_INFO_RESUME_ADDR_OFFSET 0x4
+#define PM_INFO_CPU_TYPE_OFFSET 0x8
+#define PM_INFO_PM_INFO_SIZE_OFFSET 0xC
+#define PM_INFO_MX6Q_MMDC_P_OFFSET 0x10
+#define PM_INFO_MX6Q_MMDC_V_OFFSET 0x14
+#define PM_INFO_MX6Q_SRC_P_OFFSET 0x18
+#define PM_INFO_MX6Q_SRC_V_OFFSET 0x1C
+#define PM_INFO_MX6Q_IOMUXC_P_OFFSET 0x20
+#define PM_INFO_MX6Q_IOMUXC_V_OFFSET 0x24
+#define PM_INFO_MX6Q_CCM_P_OFFSET 0x28
+#define PM_INFO_MX6Q_CCM_V_OFFSET 0x2C
+#define PM_INFO_MX6Q_GPC_P_OFFSET 0x30
+#define PM_INFO_MX6Q_GPC_V_OFFSET 0x34
+#define PM_INFO_MX6Q_L2_P_OFFSET 0x38
+#define PM_INFO_MX6Q_L2_V_OFFSET 0x3C
+#define PM_INFO_MMDC_IO_NUM_OFFSET 0x40
+#define PM_INFO_MMDC_IO_VAL_OFFSET 0x44
+
+#define MX6Q_SRC_GPR1 0x20
+#define MX6Q_SRC_GPR2 0x24
+#define MX6Q_MMDC_MAPSR 0x404
+#define MX6Q_GPC_IMR1 0x08
+#define MX6Q_GPC_IMR2 0x0c
+#define MX6Q_GPC_IMR3 0x10
+#define MX6Q_GPC_IMR4 0x14
+#define MX6Q_CCM_CCR 0x0
+
+ .align 3
+
+ .macro sync_l2_cache
+
+ /* sync L2 cache to drain L2's buffers to DRAM. */
+#ifdef CONFIG_CACHE_L2X0
+ ldr r11, [r0, #PM_INFO_MX6Q_L2_V_OFFSET]
+ mov r6, #0x0
+ str r6, [r11, #L2X0_CACHE_SYNC]
+1:
+ ldr r6, [r11, #L2X0_CACHE_SYNC]
+ ands r6, r6, #0x1
+ bne 1b
+#endif
+
+ .endm
+
+ .macro resume_mmdc
+
+ /* restore MMDC IO */
+ cmp r5, #0x0
+ ldreq r11, [r0, #PM_INFO_MX6Q_IOMUXC_V_OFFSET]
+ ldrne r11, [r0, #PM_INFO_MX6Q_IOMUXC_P_OFFSET]
+
+ ldr r6, [r0, #PM_INFO_MMDC_IO_NUM_OFFSET]
+ ldr r7, =PM_INFO_MMDC_IO_VAL_OFFSET
+ add r7, r7, r0
+1:
+ ldr r8, [r7], #0x4
+ ldr r9, [r7], #0x4
+ str r9, [r11, r8]
+ subs r6, r6, #0x1
+ bne 1b
+
+ cmp r5, #0x0
+ ldreq r11, [r0, #PM_INFO_MX6Q_MMDC_V_OFFSET]
+ ldrne r11, [r0, #PM_INFO_MX6Q_MMDC_P_OFFSET]
+
+ /* let DDR out of self-refresh */
+ ldr r7, [r11, #MX6Q_MMDC_MAPSR]
+ bic r7, r7, #(1 << 21)
+ str r7, [r11, #MX6Q_MMDC_MAPSR]
+2:
+ ldr r7, [r11, #MX6Q_MMDC_MAPSR]
+ ands r7, r7, #(1 << 25)
+ bne 2b
+
+ /* enable DDR auto power saving */
+ ldr r7, [r11, #MX6Q_MMDC_MAPSR]
+ bic r7, r7, #0x1
+ str r7, [r11, #MX6Q_MMDC_MAPSR]
+
+ .endm
+
+ENTRY(imx6_suspend)
+ ldr r1, [r0, #PM_INFO_PBASE_OFFSET]
+ ldr r2, [r0, #PM_INFO_RESUME_ADDR_OFFSET]
+ ldr r3, [r0, #PM_INFO_CPU_TYPE_OFFSET]
+ ldr r4, [r0, #PM_INFO_PM_INFO_SIZE_OFFSET]
+
+ /*
+ * counting the resume address in iram
+ * to set it in SRC register.
+ */
+ ldr r6, =imx6_suspend
+ ldr r7, =resume
+ sub r7, r7, r6
+ add r8, r1, r4
+ add r9, r8, r7
+
+ /*
+ * make sure TLB contain the addr we want,
+ * as we will access them after MMDC IO floated.
+ */
+
+ ldr r11, [r0, #PM_INFO_MX6Q_CCM_V_OFFSET]
+ ldr r6, [r11, #0x0]
+ ldr r11, [r0, #PM_INFO_MX6Q_GPC_V_OFFSET]
+ ldr r6, [r11, #0x0]
+
+ /* use r11 to store the IO address */
+ ldr r11, [r0, #PM_INFO_MX6Q_SRC_V_OFFSET]
+ /* store physical resume addr and pm_info address. */
+ str r9, [r11, #MX6Q_SRC_GPR1]
+ str r1, [r11, #MX6Q_SRC_GPR2]
+
+ /* need to sync L2 cache before DSM. */
+ sync_l2_cache
+
+ ldr r11, [r0, #PM_INFO_MX6Q_MMDC_V_OFFSET]
+ /*
+ * put DDR explicitly into self-refresh and
+ * disable automatic power savings.
+ */
+ ldr r7, [r11, #MX6Q_MMDC_MAPSR]
+ orr r7, r7, #0x1
+ str r7, [r11, #MX6Q_MMDC_MAPSR]
+
+ /* make the DDR explicitly enter self-refresh. */
+ ldr r7, [r11, #MX6Q_MMDC_MAPSR]
+ orr r7, r7, #(1 << 21)
+ str r7, [r11, #MX6Q_MMDC_MAPSR]
+
+poll_dvfs_set:
+ ldr r7, [r11, #MX6Q_MMDC_MAPSR]
+ ands r7, r7, #(1 << 25)
+ beq poll_dvfs_set
+
+ ldr r11, [r0, #PM_INFO_MX6Q_IOMUXC_V_OFFSET]
+ ldr r6, =0x0
+ ldr r7, [r0, #PM_INFO_MMDC_IO_NUM_OFFSET]
+ ldr r8, =PM_INFO_MMDC_IO_VAL_OFFSET
+ add r8, r8, r0
+set_mmdc_io_lpm:
+ ldr r9, [r8], #0x8
+ str r6, [r11, r9]
+ subs r7, r7, #0x1
+ bne set_mmdc_io_lpm
+
+ /*
+ * mask all GPC interrupts before
+ * enabling the RBC counters to
+ * avoid the counter starting too
+ * early if an interupt is already
+ * pending.
+ */
+ ldr r11, [r0, #PM_INFO_MX6Q_GPC_V_OFFSET]
+ ldr r6, [r11, #MX6Q_GPC_IMR1]
+ ldr r7, [r11, #MX6Q_GPC_IMR2]
+ ldr r8, [r11, #MX6Q_GPC_IMR3]
+ ldr r9, [r11, #MX6Q_GPC_IMR4]
+
+ ldr r10, =0xffffffff
+ str r10, [r11, #MX6Q_GPC_IMR1]
+ str r10, [r11, #MX6Q_GPC_IMR2]
+ str r10, [r11, #MX6Q_GPC_IMR3]
+ str r10, [r11, #MX6Q_GPC_IMR4]
+
+ /*
+ * enable the RBC bypass counter here
+ * to hold off the interrupts. RBC counter
+ * = 32 (1ms), Minimum RBC delay should be
+ * 400us for the analog LDOs to power down.
+ */
+ ldr r11, [r0, #PM_INFO_MX6Q_CCM_V_OFFSET]
+ ldr r10, [r11, #MX6Q_CCM_CCR]
+ bic r10, r10, #(0x3f << 21)
+ orr r10, r10, #(0x20 << 21)
+ str r10, [r11, #MX6Q_CCM_CCR]
+
+ /* enable the counter. */
+ ldr r10, [r11, #MX6Q_CCM_CCR]
+ orr r10, r10, #(0x1 << 27)
+ str r10, [r11, #MX6Q_CCM_CCR]
+
+ /* unmask all the GPC interrupts. */
+ ldr r11, [r0, #PM_INFO_MX6Q_GPC_V_OFFSET]
+ str r6, [r11, #MX6Q_GPC_IMR1]
+ str r7, [r11, #MX6Q_GPC_IMR2]
+ str r8, [r11, #MX6Q_GPC_IMR3]
+ str r9, [r11, #MX6Q_GPC_IMR4]
+
+ /*
+ * now delay for a short while (3usec)
+ * ARM is at 1GHz at this point
+ * so a short loop should be enough.
+ * this delay is required to ensure that
+ * the RBC counter can start counting in
+ * case an interrupt is already pending
+ * or in case an interrupt arrives just
+ * as ARM is about to assert DSM_request.
+ */
+ ldr r6, =2000
+rbc_loop:
+ subs r6, r6, #0x1
+ bne rbc_loop
+
+ /* Zzz, enter stop mode */
+ wfi
+ nop
+ nop
+ nop
+ nop
+
+ /*
+ * run to here means there is pending
+ * wakeup source, system should auto
+ * resume, we need to restore MMDC IO first
+ */
+ mov r5, #0x0
+ resume_mmdc
+
+ /* return to suspend finish */
+ mov pc, lr
+
+resume:
+ /* invalidate L1 I-cache first */
+ mov r6, #0x0
+ mcr p15, 0, r6, c7, c5, 0
+ mcr p15, 0, r6, c7, c5, 6
+ /* enable the Icache and branch prediction */
+ mov r6, #0x1800
+ mcr p15, 0, r6, c1, c0, 0
+ isb
+
+ /* get physical resume address from pm_info. */
+ ldr lr, [r0, #PM_INFO_RESUME_ADDR_OFFSET]
+ /* clear core0's entry and parameter */
+ ldr r11, [r0, #PM_INFO_MX6Q_SRC_P_OFFSET]
+ mov r7, #0x0
+ str r7, [r11, #MX6Q_SRC_GPR1]
+ str r7, [r11, #MX6Q_SRC_GPR2]
+
+ mov r5, #0x1
+ resume_mmdc
+
+ mov pc, lr
+ENDPROC(imx6_suspend)