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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/arm/mach-mxs
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/arm/mach-mxs')
-rw-r--r--kernel/arch/arm/mach-mxs/Kconfig26
-rw-r--r--kernel/arch/arm/mach-mxs/Makefile2
-rw-r--r--kernel/arch/arm/mach-mxs/mach-mxs.c543
-rw-r--r--kernel/arch/arm/mach-mxs/pm.c41
-rw-r--r--kernel/arch/arm/mach-mxs/pm.h18
5 files changed, 630 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-mxs/Kconfig b/kernel/arch/arm/mach-mxs/Kconfig
new file mode 100644
index 000000000..84794137b
--- /dev/null
+++ b/kernel/arch/arm/mach-mxs/Kconfig
@@ -0,0 +1,26 @@
+config SOC_IMX23
+ bool
+ select ARM_AMBA
+ select ARM_CPU_SUSPEND if PM
+ select CPU_ARM926T
+ select PINCTRL_IMX23
+
+config SOC_IMX28
+ bool
+ select ARM_AMBA
+ select ARM_CPU_SUSPEND if PM
+ select CPU_ARM926T
+ select PINCTRL_IMX28
+
+config ARCH_MXS
+ bool "Freescale MXS (i.MX23, i.MX28) support"
+ depends on ARCH_MULTI_V5
+ select ARCH_REQUIRE_GPIOLIB
+ select CLKSRC_MMIO
+ select PINCTRL
+ select SOC_BUS
+ select SOC_IMX23
+ select SOC_IMX28
+ select STMP_DEVICE
+ help
+ Support for Freescale MXS-based family of processors
diff --git a/kernel/arch/arm/mach-mxs/Makefile b/kernel/arch/arm/mach-mxs/Makefile
new file mode 100644
index 000000000..cc2bf6748
--- /dev/null
+++ b/kernel/arch/arm/mach-mxs/Makefile
@@ -0,0 +1,2 @@
+obj-$(CONFIG_PM) += pm.o
+obj-$(CONFIG_ARCH_MXS) += mach-mxs.o
diff --git a/kernel/arch/arm/mach-mxs/mach-mxs.c b/kernel/arch/arm/mach-mxs/mach-mxs.c
new file mode 100644
index 000000000..2e7cec86e
--- /dev/null
+++ b/kernel/arch/arm/mach-mxs/mach-mxs.c
@@ -0,0 +1,543 @@
+/*
+ * Copyright 2012 Freescale Semiconductor, Inc.
+ * Copyright 2012 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/clk.h>
+#include <linux/clk/mxs.h>
+#include <linux/clkdev.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/init.h>
+#include <linux/irqchip/mxs.h>
+#include <linux/reboot.h>
+#include <linux/micrel_phy.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/phy.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/sys_soc.h>
+#include <asm/mach/arch.h>
+#include <asm/mach/map.h>
+#include <asm/mach/time.h>
+#include <asm/system_misc.h>
+
+#include "pm.h"
+
+/* MXS DIGCTL SAIF CLKMUX */
+#define MXS_DIGCTL_SAIF_CLKMUX_DIRECT 0x0
+#define MXS_DIGCTL_SAIF_CLKMUX_CROSSINPUT 0x1
+#define MXS_DIGCTL_SAIF_CLKMUX_EXTMSTR0 0x2
+#define MXS_DIGCTL_SAIF_CLKMUX_EXTMSTR1 0x3
+
+#define HW_DIGCTL_CHIPID 0x310
+#define HW_DIGCTL_CHIPID_MASK (0xffff << 16)
+#define HW_DIGCTL_REV_MASK 0xff
+#define HW_DIGCTL_CHIPID_MX23 (0x3780 << 16)
+#define HW_DIGCTL_CHIPID_MX28 (0x2800 << 16)
+
+#define MXS_CHIP_REVISION_1_0 0x10
+#define MXS_CHIP_REVISION_1_1 0x11
+#define MXS_CHIP_REVISION_1_2 0x12
+#define MXS_CHIP_REVISION_1_3 0x13
+#define MXS_CHIP_REVISION_1_4 0x14
+#define MXS_CHIP_REV_UNKNOWN 0xff
+
+#define MXS_GPIO_NR(bank, nr) ((bank) * 32 + (nr))
+
+#define MXS_SET_ADDR 0x4
+#define MXS_CLR_ADDR 0x8
+#define MXS_TOG_ADDR 0xc
+
+static u32 chipid;
+static u32 socid;
+
+static void __iomem *reset_addr;
+
+static inline void __mxs_setl(u32 mask, void __iomem *reg)
+{
+ __raw_writel(mask, reg + MXS_SET_ADDR);
+}
+
+static inline void __mxs_clrl(u32 mask, void __iomem *reg)
+{
+ __raw_writel(mask, reg + MXS_CLR_ADDR);
+}
+
+static inline void __mxs_togl(u32 mask, void __iomem *reg)
+{
+ __raw_writel(mask, reg + MXS_TOG_ADDR);
+}
+
+#define OCOTP_WORD_OFFSET 0x20
+#define OCOTP_WORD_COUNT 0x20
+
+#define BM_OCOTP_CTRL_BUSY (1 << 8)
+#define BM_OCOTP_CTRL_ERROR (1 << 9)
+#define BM_OCOTP_CTRL_RD_BANK_OPEN (1 << 12)
+
+static DEFINE_MUTEX(ocotp_mutex);
+static u32 ocotp_words[OCOTP_WORD_COUNT];
+
+static const u32 *mxs_get_ocotp(void)
+{
+ struct device_node *np;
+ void __iomem *ocotp_base;
+ int timeout = 0x400;
+ size_t i;
+ static int once;
+
+ if (once)
+ return ocotp_words;
+
+ np = of_find_compatible_node(NULL, NULL, "fsl,ocotp");
+ ocotp_base = of_iomap(np, 0);
+ WARN_ON(!ocotp_base);
+
+ mutex_lock(&ocotp_mutex);
+
+ /*
+ * clk_enable(hbus_clk) for ocotp can be skipped
+ * as it must be on when system is running.
+ */
+
+ /* try to clear ERROR bit */
+ __mxs_clrl(BM_OCOTP_CTRL_ERROR, ocotp_base);
+
+ /* check both BUSY and ERROR cleared */
+ while ((__raw_readl(ocotp_base) &
+ (BM_OCOTP_CTRL_BUSY | BM_OCOTP_CTRL_ERROR)) && --timeout)
+ cpu_relax();
+
+ if (unlikely(!timeout))
+ goto error_unlock;
+
+ /* open OCOTP banks for read */
+ __mxs_setl(BM_OCOTP_CTRL_RD_BANK_OPEN, ocotp_base);
+
+ /* approximately wait 32 hclk cycles */
+ udelay(1);
+
+ /* poll BUSY bit becoming cleared */
+ timeout = 0x400;
+ while ((__raw_readl(ocotp_base) & BM_OCOTP_CTRL_BUSY) && --timeout)
+ cpu_relax();
+
+ if (unlikely(!timeout))
+ goto error_unlock;
+
+ for (i = 0; i < OCOTP_WORD_COUNT; i++)
+ ocotp_words[i] = __raw_readl(ocotp_base + OCOTP_WORD_OFFSET +
+ i * 0x10);
+
+ /* close banks for power saving */
+ __mxs_clrl(BM_OCOTP_CTRL_RD_BANK_OPEN, ocotp_base);
+
+ once = 1;
+
+ mutex_unlock(&ocotp_mutex);
+
+ return ocotp_words;
+
+error_unlock:
+ mutex_unlock(&ocotp_mutex);
+ pr_err("%s: timeout in reading OCOTP\n", __func__);
+ return NULL;
+}
+
+enum mac_oui {
+ OUI_FSL,
+ OUI_DENX,
+ OUI_CRYSTALFONTZ,
+ OUI_I2SE,
+ OUI_ARMADEUS,
+};
+
+static void __init update_fec_mac_prop(enum mac_oui oui)
+{
+ struct device_node *np, *from = NULL;
+ struct property *newmac;
+ const u32 *ocotp = mxs_get_ocotp();
+ u8 *macaddr;
+ u32 val;
+ int i;
+
+ for (i = 0; i < 2; i++) {
+ np = of_find_compatible_node(from, NULL, "fsl,imx28-fec");
+ if (!np)
+ return;
+
+ from = np;
+
+ if (of_get_property(np, "local-mac-address", NULL))
+ continue;
+
+ newmac = kzalloc(sizeof(*newmac) + 6, GFP_KERNEL);
+ if (!newmac)
+ return;
+ newmac->value = newmac + 1;
+ newmac->length = 6;
+
+ newmac->name = kstrdup("local-mac-address", GFP_KERNEL);
+ if (!newmac->name) {
+ kfree(newmac);
+ return;
+ }
+
+ /*
+ * OCOTP only stores the last 4 octets for each mac address,
+ * so hard-code OUI here.
+ */
+ macaddr = newmac->value;
+ switch (oui) {
+ case OUI_FSL:
+ macaddr[0] = 0x00;
+ macaddr[1] = 0x04;
+ macaddr[2] = 0x9f;
+ break;
+ case OUI_DENX:
+ macaddr[0] = 0xc0;
+ macaddr[1] = 0xe5;
+ macaddr[2] = 0x4e;
+ break;
+ case OUI_CRYSTALFONTZ:
+ macaddr[0] = 0x58;
+ macaddr[1] = 0xb9;
+ macaddr[2] = 0xe1;
+ break;
+ case OUI_I2SE:
+ macaddr[0] = 0x00;
+ macaddr[1] = 0x01;
+ macaddr[2] = 0x87;
+ break;
+ case OUI_ARMADEUS:
+ macaddr[0] = 0x00;
+ macaddr[1] = 0x1e;
+ macaddr[2] = 0xac;
+ break;
+ }
+ val = ocotp[i];
+ macaddr[3] = (val >> 16) & 0xff;
+ macaddr[4] = (val >> 8) & 0xff;
+ macaddr[5] = (val >> 0) & 0xff;
+
+ of_update_property(np, newmac);
+ }
+}
+
+static inline void enable_clk_enet_out(void)
+{
+ struct clk *clk = clk_get_sys("enet_out", NULL);
+
+ if (!IS_ERR(clk))
+ clk_prepare_enable(clk);
+}
+
+static void __init imx28_evk_init(void)
+{
+ update_fec_mac_prop(OUI_FSL);
+
+ mxs_saif_clkmux_select(MXS_DIGCTL_SAIF_CLKMUX_EXTMSTR0);
+}
+
+static void __init imx28_apf28_init(void)
+{
+ update_fec_mac_prop(OUI_ARMADEUS);
+}
+
+static int apx4devkit_phy_fixup(struct phy_device *phy)
+{
+ phy->dev_flags |= MICREL_PHY_50MHZ_CLK;
+ return 0;
+}
+
+static void __init apx4devkit_init(void)
+{
+ enable_clk_enet_out();
+
+ if (IS_BUILTIN(CONFIG_PHYLIB))
+ phy_register_fixup_for_uid(PHY_ID_KSZ8051, MICREL_PHY_ID_MASK,
+ apx4devkit_phy_fixup);
+}
+
+#define ENET0_MDC__GPIO_4_0 MXS_GPIO_NR(4, 0)
+#define ENET0_MDIO__GPIO_4_1 MXS_GPIO_NR(4, 1)
+#define ENET0_RX_EN__GPIO_4_2 MXS_GPIO_NR(4, 2)
+#define ENET0_RXD0__GPIO_4_3 MXS_GPIO_NR(4, 3)
+#define ENET0_RXD1__GPIO_4_4 MXS_GPIO_NR(4, 4)
+#define ENET0_TX_EN__GPIO_4_6 MXS_GPIO_NR(4, 6)
+#define ENET0_TXD0__GPIO_4_7 MXS_GPIO_NR(4, 7)
+#define ENET0_TXD1__GPIO_4_8 MXS_GPIO_NR(4, 8)
+#define ENET_CLK__GPIO_4_16 MXS_GPIO_NR(4, 16)
+
+#define TX28_FEC_PHY_POWER MXS_GPIO_NR(3, 29)
+#define TX28_FEC_PHY_RESET MXS_GPIO_NR(4, 13)
+#define TX28_FEC_nINT MXS_GPIO_NR(4, 5)
+
+static const struct gpio tx28_gpios[] __initconst = {
+ { ENET0_MDC__GPIO_4_0, GPIOF_OUT_INIT_LOW, "GPIO_4_0" },
+ { ENET0_MDIO__GPIO_4_1, GPIOF_OUT_INIT_LOW, "GPIO_4_1" },
+ { ENET0_RX_EN__GPIO_4_2, GPIOF_OUT_INIT_LOW, "GPIO_4_2" },
+ { ENET0_RXD0__GPIO_4_3, GPIOF_OUT_INIT_LOW, "GPIO_4_3" },
+ { ENET0_RXD1__GPIO_4_4, GPIOF_OUT_INIT_LOW, "GPIO_4_4" },
+ { ENET0_TX_EN__GPIO_4_6, GPIOF_OUT_INIT_LOW, "GPIO_4_6" },
+ { ENET0_TXD0__GPIO_4_7, GPIOF_OUT_INIT_LOW, "GPIO_4_7" },
+ { ENET0_TXD1__GPIO_4_8, GPIOF_OUT_INIT_LOW, "GPIO_4_8" },
+ { ENET_CLK__GPIO_4_16, GPIOF_OUT_INIT_LOW, "GPIO_4_16" },
+ { TX28_FEC_PHY_POWER, GPIOF_OUT_INIT_LOW, "fec-phy-power" },
+ { TX28_FEC_PHY_RESET, GPIOF_OUT_INIT_LOW, "fec-phy-reset" },
+ { TX28_FEC_nINT, GPIOF_DIR_IN, "fec-int" },
+};
+
+static void __init tx28_post_init(void)
+{
+ struct device_node *np;
+ struct platform_device *pdev;
+ struct pinctrl *pctl;
+ int ret;
+
+ enable_clk_enet_out();
+
+ np = of_find_compatible_node(NULL, NULL, "fsl,imx28-fec");
+ pdev = of_find_device_by_node(np);
+ if (!pdev) {
+ pr_err("%s: failed to find fec device\n", __func__);
+ return;
+ }
+
+ pctl = pinctrl_get_select(&pdev->dev, "gpio_mode");
+ if (IS_ERR(pctl)) {
+ pr_err("%s: failed to get pinctrl state\n", __func__);
+ return;
+ }
+
+ ret = gpio_request_array(tx28_gpios, ARRAY_SIZE(tx28_gpios));
+ if (ret) {
+ pr_err("%s: failed to request gpios: %d\n", __func__, ret);
+ return;
+ }
+
+ /* Power up fec phy */
+ gpio_set_value(TX28_FEC_PHY_POWER, 1);
+ msleep(26); /* 25ms according to data sheet */
+
+ /* Mode strap pins */
+ gpio_set_value(ENET0_RX_EN__GPIO_4_2, 1);
+ gpio_set_value(ENET0_RXD0__GPIO_4_3, 1);
+ gpio_set_value(ENET0_RXD1__GPIO_4_4, 1);
+
+ udelay(100); /* minimum assertion time for nRST */
+
+ /* Deasserting FEC PHY RESET */
+ gpio_set_value(TX28_FEC_PHY_RESET, 1);
+
+ pinctrl_put(pctl);
+}
+
+static void __init crystalfontz_init(void)
+{
+ update_fec_mac_prop(OUI_CRYSTALFONTZ);
+}
+
+static void __init duckbill_init(void)
+{
+ update_fec_mac_prop(OUI_I2SE);
+}
+
+static void __init m28cu3_init(void)
+{
+ update_fec_mac_prop(OUI_DENX);
+}
+
+static const char __init *mxs_get_soc_id(void)
+{
+ struct device_node *np;
+ void __iomem *digctl_base;
+
+ np = of_find_compatible_node(NULL, NULL, "fsl,imx23-digctl");
+ digctl_base = of_iomap(np, 0);
+ WARN_ON(!digctl_base);
+
+ chipid = readl(digctl_base + HW_DIGCTL_CHIPID);
+ socid = chipid & HW_DIGCTL_CHIPID_MASK;
+
+ iounmap(digctl_base);
+ of_node_put(np);
+
+ switch (socid) {
+ case HW_DIGCTL_CHIPID_MX23:
+ return "i.MX23";
+ case HW_DIGCTL_CHIPID_MX28:
+ return "i.MX28";
+ default:
+ return "Unknown";
+ }
+}
+
+static u32 __init mxs_get_cpu_rev(void)
+{
+ u32 rev = chipid & HW_DIGCTL_REV_MASK;
+
+ switch (socid) {
+ case HW_DIGCTL_CHIPID_MX23:
+ switch (rev) {
+ case 0x0:
+ return MXS_CHIP_REVISION_1_0;
+ case 0x1:
+ return MXS_CHIP_REVISION_1_1;
+ case 0x2:
+ return MXS_CHIP_REVISION_1_2;
+ case 0x3:
+ return MXS_CHIP_REVISION_1_3;
+ case 0x4:
+ return MXS_CHIP_REVISION_1_4;
+ default:
+ return MXS_CHIP_REV_UNKNOWN;
+ }
+ case HW_DIGCTL_CHIPID_MX28:
+ switch (rev) {
+ case 0x0:
+ return MXS_CHIP_REVISION_1_1;
+ case 0x1:
+ return MXS_CHIP_REVISION_1_2;
+ default:
+ return MXS_CHIP_REV_UNKNOWN;
+ }
+ default:
+ return MXS_CHIP_REV_UNKNOWN;
+ }
+}
+
+static const char __init *mxs_get_revision(void)
+{
+ u32 rev = mxs_get_cpu_rev();
+
+ if (rev != MXS_CHIP_REV_UNKNOWN)
+ return kasprintf(GFP_KERNEL, "%d.%d", (rev >> 4) & 0xf,
+ rev & 0xf);
+ else
+ return kasprintf(GFP_KERNEL, "%s", "Unknown");
+}
+
+#define MX23_CLKCTRL_RESET_OFFSET 0x120
+#define MX28_CLKCTRL_RESET_OFFSET 0x1e0
+
+static int __init mxs_restart_init(void)
+{
+ struct device_node *np;
+
+ np = of_find_compatible_node(NULL, NULL, "fsl,clkctrl");
+ reset_addr = of_iomap(np, 0);
+ if (!reset_addr)
+ return -ENODEV;
+
+ if (of_device_is_compatible(np, "fsl,imx23-clkctrl"))
+ reset_addr += MX23_CLKCTRL_RESET_OFFSET;
+ else
+ reset_addr += MX28_CLKCTRL_RESET_OFFSET;
+ of_node_put(np);
+
+ return 0;
+}
+
+static void __init eukrea_mbmx283lc_init(void)
+{
+ mxs_saif_clkmux_select(MXS_DIGCTL_SAIF_CLKMUX_EXTMSTR0);
+}
+
+static void __init mxs_machine_init(void)
+{
+ struct device_node *root;
+ struct device *parent;
+ struct soc_device *soc_dev;
+ struct soc_device_attribute *soc_dev_attr;
+ int ret;
+
+ soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
+ if (!soc_dev_attr)
+ return;
+
+ root = of_find_node_by_path("/");
+ ret = of_property_read_string(root, "model", &soc_dev_attr->machine);
+ if (ret)
+ return;
+
+ soc_dev_attr->family = "Freescale MXS Family";
+ soc_dev_attr->soc_id = mxs_get_soc_id();
+ soc_dev_attr->revision = mxs_get_revision();
+
+ soc_dev = soc_device_register(soc_dev_attr);
+ if (IS_ERR(soc_dev)) {
+ kfree(soc_dev_attr->revision);
+ kfree(soc_dev_attr);
+ return;
+ }
+
+ parent = soc_device_to_device(soc_dev);
+
+ if (of_machine_is_compatible("fsl,imx28-evk"))
+ imx28_evk_init();
+ if (of_machine_is_compatible("armadeus,imx28-apf28"))
+ imx28_apf28_init();
+ else if (of_machine_is_compatible("bluegiga,apx4devkit"))
+ apx4devkit_init();
+ else if (of_machine_is_compatible("crystalfontz,cfa10036"))
+ crystalfontz_init();
+ else if (of_machine_is_compatible("eukrea,mbmx283lc"))
+ eukrea_mbmx283lc_init();
+ else if (of_machine_is_compatible("i2se,duckbill"))
+ duckbill_init();
+ else if (of_machine_is_compatible("msr,m28cu3"))
+ m28cu3_init();
+
+ of_platform_populate(NULL, of_default_bus_match_table,
+ NULL, parent);
+
+ mxs_restart_init();
+
+ if (of_machine_is_compatible("karo,tx28"))
+ tx28_post_init();
+}
+
+#define MXS_CLKCTRL_RESET_CHIP (1 << 1)
+
+/*
+ * Reset the system. It is called by machine_restart().
+ */
+static void mxs_restart(enum reboot_mode mode, const char *cmd)
+{
+ if (reset_addr) {
+ /* reset the chip */
+ __mxs_setl(MXS_CLKCTRL_RESET_CHIP, reset_addr);
+
+ pr_err("Failed to assert the chip reset\n");
+
+ /* Delay to allow the serial port to show the message */
+ mdelay(50);
+ }
+
+ /* We'll take a jump through zero as a poor second */
+ soft_restart(0);
+}
+
+static const char *mxs_dt_compat[] __initdata = {
+ "fsl,imx28",
+ "fsl,imx23",
+ NULL,
+};
+
+DT_MACHINE_START(MXS, "Freescale MXS (Device Tree)")
+ .handle_irq = icoll_handle_irq,
+ .init_machine = mxs_machine_init,
+ .init_late = mxs_pm_init,
+ .dt_compat = mxs_dt_compat,
+ .restart = mxs_restart,
+MACHINE_END
diff --git a/kernel/arch/arm/mach-mxs/pm.c b/kernel/arch/arm/mach-mxs/pm.c
new file mode 100644
index 000000000..0170e99fd
--- /dev/null
+++ b/kernel/arch/arm/mach-mxs/pm.c
@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2010 Freescale Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/suspend.h>
+#include <linux/io.h>
+#include "pm.h"
+
+static int mxs_suspend_enter(suspend_state_t state)
+{
+ switch (state) {
+ case PM_SUSPEND_MEM:
+ cpu_do_idle();
+ break;
+
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static struct platform_suspend_ops mxs_suspend_ops = {
+ .enter = mxs_suspend_enter,
+ .valid = suspend_valid_only_mem,
+};
+
+void __init mxs_pm_init(void)
+{
+ suspend_set_ops(&mxs_suspend_ops);
+}
diff --git a/kernel/arch/arm/mach-mxs/pm.h b/kernel/arch/arm/mach-mxs/pm.h
new file mode 100644
index 000000000..09d77b00a
--- /dev/null
+++ b/kernel/arch/arm/mach-mxs/pm.h
@@ -0,0 +1,18 @@
+/*
+ * Copyright (C) 2013 Freescale Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef __ARCH_MXS_PM_H
+#define __ARCH_MXS_PM_H
+
+#ifdef CONFIG_PM
+void mxs_pm_init(void);
+#else
+#define mxs_pm_init NULL
+#endif
+
+#endif