[PATCH V3 1/5] ARM: imx: add suspend in ocram support on i.mx6q
Shawn Guo
shawn.guo at linaro.org
Mon Jan 13 03:05:07 EST 2014
On Mon, Jan 13, 2014 at 01:58:34PM +0800, Anson Huang wrote:
> When system enter suspend, we can set the DDR IO
> to high-Z state to save DDR IO's power, this operation
> can save many power(from ~26mA at 1.5V to ~15mA at 1.5V,
> measured on i.MX6Q/DL SabreSD board, R25) of DDR IO. To
> achieve that, we need to copy the suspend code to ocram
> and run the low level hardware related code(set DDR IO
> to high-Z) in ocram.
>
> If there is no ocram space available, then system will
> still do suspend in DDR, hence no DDR IO will be set
> to high-Z.
>
> The OCRAM usage layout is as below,
>
> ocram suspend region:
> ======================== high address ======================
> .
> .
> .
> ^
> ^
> ^
> imx6_suspend code
> reserved region(to make imx6_suspend aligned with 8)
> PM_INFO structure(imx6_cpu_pm_info)
> ======================== low address =======================
>
> Signed-off-by: Anson Huang <b20788 at freescale.com>
> ---
> Changes since V2:
> 1. save MMDC IO info during initialization for once, no
> need to do save everytime before suspend;
> 2. Improve ocram suspend initialization, put all of them
> into a function;
> 3. Improve the initialization of pm_info's modules, create
> a function call for them.
Thanks for the rework.
>
> arch/arm/mach-imx/Makefile | 3 +-
> arch/arm/mach-imx/common.h | 4 +-
> arch/arm/mach-imx/hardware.h | 4 +-
> arch/arm/mach-imx/pm-imx6q.c | 244 +++++++++++++++++++++++++++++-
> arch/arm/mach-imx/suspend-imx6.S | 306 ++++++++++++++++++++++++++++++++++++++
> 5 files changed, 554 insertions(+), 7 deletions(-)
> create mode 100644 arch/arm/mach-imx/suspend-imx6.S
>
> diff --git a/arch/arm/mach-imx/Makefile b/arch/arm/mach-imx/Makefile
> index befcaf5..3d96a45 100644
> --- a/arch/arm/mach-imx/Makefile
> +++ b/arch/arm/mach-imx/Makefile
> @@ -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
> diff --git a/arch/arm/mach-imx/common.h b/arch/arm/mach-imx/common.h
> index 4f4a95c..7c249e1 100644
> --- a/arch/arm/mach-imx/common.h
> +++ b/arch/arm/mach-imx/common.h
> @@ -1,5 +1,5 @@
> /*
> - * Copyright 2004-2013 Freescale Semiconductor, Inc. All Rights Reserved.
> + * Copyright 2004-2014 Freescale Semiconductor, Inc. All Rights Reserved.
> */
>
> /*
> @@ -145,10 +145,12 @@ void imx_cpu_die(unsigned int cpu);
> int imx_cpu_kill(unsigned int cpu);
>
> #ifdef CONFIG_PM
> +void imx6_suspend(void);
> void imx6q_pm_init(void);
> void imx6q_pm_set_ccm_base(void __iomem *base);
> void imx5_pm_init(void);
> #else
> +static inline void imx6_suspend(void) {}
> static inline void imx6q_pm_init(void) {}
> static inline void imx6q_pm_set_ccm_base(void __iomem *base) {}
> static inline void imx5_pm_init(void) {}
> diff --git a/arch/arm/mach-imx/hardware.h b/arch/arm/mach-imx/hardware.h
> index a3b0b04..abf43bb 100644
> --- a/arch/arm/mach-imx/hardware.h
> +++ b/arch/arm/mach-imx/hardware.h
> @@ -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 at 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) \
> diff --git a/arch/arm/mach-imx/pm-imx6q.c b/arch/arm/mach-imx/pm-imx6q.c
> index d45acc0..8997f58 100644
> --- a/arch/arm/mach-imx/pm-imx6q.c
> +++ b/arch/arm/mach-imx/pm-imx6q.c
> @@ -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 +14,21 @@
> #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/hardware/cache-l2x0.h>
While at it, we may want to just remove it, since it's used nowhere in
the file now.
> +#include <asm/mach/map.h>
Since you have killed static mapping, you do not need this anymore.
> #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 +63,69 @@
> #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
> +#define MX6Q_MMDC_IO_NUM 33
> +
> static void __iomem *ccm_base;
> +static void __iomem *suspend_ocram_base;
> +static int (*imx6_suspend_in_ocram_fn)(void __iomem *ocram_vbase);
> +
> +/*
> + * suspend ocram space layout:
> + * ======================== high address ======================
> + * .
> + * .
> + * .
> + * ^
> + * ^
> + * ^
> + * imx6_suspend code
> + * reserved region(to make imx6_suspend aligned with 8)
> + * PM_INFO structure(imx6_cpu_pm_info)
> + * ======================== low address =======================
> + */
> +
> +struct imx6_pm_base {
> + phys_addr_t pbase;
> + void __iomem *vbase;
> +};
> +
> +static u32 imx6q_mmdc_io_dsm_offset[] = {
> + 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, DDRMODE_CTL, DDRMODE */
> + 0x74c /* GPR_ADDS */
> +};
> +
> +/*
> + * 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 fucntion 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;
> + /* reserve some space to make ocram function's address aligned with 8 */
> + u32 reserved_size;
> + 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 */
> +};
Since the address we get from gen_pool is 32-bytes aligned, we can
ensure the 8-bytes alignment of the function pointer by enforcing the
alignment of imx6_cpu_pm_info with __attribute__((__aligned__(8))).
Then we can save that reserved_size?
>
> void imx6q_set_int_mem_clk_lpm(void)
> {
> @@ -177,7 +244,17 @@ 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 +264,12 @@ 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 +300,166 @@ void __init imx6q_pm_set_ccm_base(void __iomem *base)
> ccm_base = base;
> }
>
> +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(void)
> +{
> + 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, reserved_size;
> + int i, ret = 0;
> +
> + 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);
> + reserved_size = 8 - ((ocram_pbase + sizeof(*pm_info)) % 8);
> +
> + 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);
> + pm_info->reserved_size = reserved_size;
> +
> + /*
> + * 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, "fsl,imx6q-mmdc");
> + 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, "fsl,imx6q-src");
> + 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, "fsl,imx6q-iomuxc");
> + 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, "fsl,imx6q-gpc");
> + 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;
> + }
> +
> + if (cpu_is_imx6q()) {
> + pm_info->cpu_type = MXC_CPU_IMX6Q;
> + pm_info->mmdc_io_num = MX6Q_MMDC_IO_NUM;
ARRAY_SIZE(imx6q_mmdc_io_dsm_offset), so that you can save the macro.
> + for (i = 0; i < MX6Q_MMDC_IO_NUM; i++) {
> + pm_info->mmdc_io_val[i][0] =
> + imx6q_mmdc_io_dsm_offset[i];
> + pm_info->mmdc_io_val[i][1] =
> + readl_relaxed(*(&pm_info->iomuxc_base.vbase) +
> + imx6q_mmdc_io_dsm_offset[i]);
> + }
This for-loop could stay out of the if-check by using
pm_info->mmdc_io_num.
> + }
> +
> + imx6_suspend_in_ocram_fn = (void *)fncpy(
> + suspend_ocram_base + sizeof(*pm_info) + reserved_size,
> + &imx6_suspend,
> + MX6Q_SUSPEND_OCRAM_SIZE - sizeof(*pm_info) - reserved_size);
> +
> + 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;
> +}
> +
> void __init imx6q_pm_init(void)
> {
> struct regmap *gpr;
> + int ret;
>
> WARN_ON(!ccm_base);
>
> + ret = imx6q_ocram_suspend_init();
> + 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.
> diff --git a/arch/arm/mach-imx/suspend-imx6.S b/arch/arm/mach-imx/suspend-imx6.S
> new file mode 100644
> index 0000000..da1f806
> --- /dev/null
> +++ b/arch/arm/mach-imx/suspend-imx6.S
> @@ -0,0 +1,306 @@
> +/*
> + * 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 ~ r5: for saving pm_info members;
> + * r6 ~ r10: free registers;
> + * r11: io base address.
> + *
> + * suspend ocram space layout:
> + * ======================== high address ======================
> + * .
> + * .
> + * .
> + * ^
> + * ^
> + * ^
> + * imx6_suspend code
> + * reserved region(to make imx6_suspend aligned with 8)
> + * 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_RESERVED_SIZE_OFFSET 0x40
> +#define PM_INFO_MMDC_IO_NUM_OFFSET 0x44
> +#define PM_INFO_MMDC_IO_VAL_OFFSET 0x48
> +
> +#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
> +
> +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]
> + ldr r5, [r0, #PM_INFO_RESERVED_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 r8, r8, r5
> + 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_1:
> + ldr r7, [r11, #0x404]
s/0x404/MX6Q_MMDC_MAPSR
Shawn
> + ands r7, r7, #(1 << 25)
> + beq poll_dvfs_set_1
> +
> + 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
> +set_mmdc_io_lpm:
> + ldr r9, [r0, r8]
> + str r6, [r11, r9]
> + add r8, r8, #0x8
> + sub r7, r7, #0x1
> + cmp r7, #0x0
> + 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:
> + sub r6, r6, #0x1
> + cmp r6, #0x0
> + 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
> + */
> + ldr r11, [r0, #PM_INFO_MX6Q_IOMUXC_V_OFFSET]
> + ldr r6, [r0, #PM_INFO_MMDC_IO_NUM_OFFSET]
> + ldr r7, =PM_INFO_MMDC_IO_VAL_OFFSET
> +restore_mmdc_io:
> + ldr r8, [r0, r7]
> + add r7, r7, #0x4
> + ldr r9, [r0, r7]
> + add r7, r7, #0x4
> + str r9, [r11, r8]
> + sub r6, r6, #0x1
> + cmp r6, #0x0
> + bne restore_mmdc_io
> +
> + ldr r11, [r0, #PM_INFO_MX6Q_MMDC_V_OFFSET]
> + /* let DDR out of self-refresh. */
> + ldr r7, [r11, #MX6Q_MMDC_MAPSR]
> + bic r7, r7, #(1 << 21)
> + str r7, [r11, #MX6Q_MMDC_MAPSR]
> +
> +poll_dvfs_clear_2:
> + ldr r7, [r11, #MX6Q_MMDC_MAPSR]
> + ands r7, r7, #(1 << 25)
> + bne poll_dvfs_clear_2
> + /* enable DDR auto power saving */
> + ldr r7, [r11, #MX6Q_MMDC_MAPSR]
> + bic r7, r7, #0x1
> + str r7, [r11, #MX6Q_MMDC_MAPSR]
> + /* 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, 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, #0
> + str r7, [r11, #MX6Q_SRC_GPR1]
> + str r7, [r11, #MX6Q_SRC_GPR2]
> +
> + ldr 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
> +dsm_restore_mmdc_io:
> + ldr r8, [r0, r7]
> + add r7, r7, #0x4
> + ldr r9, [r0, r7]
> + add r7, r7, #0x4
> + str r9, [r11, r8]
> + sub r6, r6, #0x1
> + cmp r6, #0x0
> + bne dsm_restore_mmdc_io
> +
> + ldr 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]
> +
> +poll_dvfs_clear_1:
> + ldr r7, [r11, #MX6Q_MMDC_MAPSR]
> + ands r7, r7, #(1 << 25)
> + bne poll_dvfs_clear_1
> + /* enable DDR auto power saving */
> + ldr r7, [r11, #MX6Q_MMDC_MAPSR]
> + bic r7, r7, #0x1
> + str r7, [r11, #MX6Q_MMDC_MAPSR]
> + mov pc, lr
> +ENDPROC(imx6_suspend)
> --
> 1.7.9.5
>
>
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