ARM: imx: add i.MX7ULP cpuidle support

This patch adds cpuidle support for i.MX7ULP, 3 cpuidle
states supported as below:

1. WFI, just ARM wfi;
2. WAIT mode, mapped to SoC's partial stop mode #3;
3. STOP mode, mapped to SoC's partial stop mode #1.

In WAIT mode, system clock and bus clock will be enabled;
In STOP mode, system clock and bus clock will be disabled.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

diff --git a/arch/arm/mach-imx/Makefile b/arch/arm/mach-imx/Makefile
index b6c87d7..35ff620 100644 (file)
--- a/arch/arm/mach-imx/Makefile
+++ b/arch/arm/mach-imx/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_SOC_IMX6SL) += cpuidle-imx6sl.o
 obj-$(CONFIG_SOC_IMX6SLL) += cpuidle-imx6sx.o
 obj-$(CONFIG_SOC_IMX6SX) += cpuidle-imx6sx.o
 obj-$(CONFIG_SOC_IMX6UL) += cpuidle-imx6sx.o
+obj-$(CONFIG_SOC_IMX7ULP) += cpuidle-imx7ulp.o
 endif
 
 ifdef CONFIG_SND_SOC_IMX_PCM_FIQ

diff --git a/arch/arm/mach-imx/common.h b/arch/arm/mach-imx/common.h
index bc915e5..c51764a 100644 (file)
--- a/arch/arm/mach-imx/common.h
+++ b/arch/arm/mach-imx/common.h
@@ -72,6 +72,15 @@ enum mxc_cpu_pwr_mode {
        STOP_POWER_OFF,         /* STOP + SRPG */
 };
 
+enum ulp_cpu_pwr_mode {
+       ULP_PM_HSRUN,    /* High speed run mode */
+       ULP_PM_RUN,      /* Run mode */
+       ULP_PM_WAIT,     /* Wait mode */
+       ULP_PM_STOP,     /* Stop mode */
+       ULP_PM_VLPS,     /* Very low power stop mode */
+       ULP_PM_VLLS,     /* very low leakage stop mode */
+};
+
 void imx_enable_cpu(int cpu, bool enable);
 void imx_set_cpu_jump(int cpu, void *jump_addr);
 u32 imx_get_cpu_arg(int cpu);
@@ -98,6 +107,7 @@ int imx6_set_lpm(enum mxc_cpu_pwr_mode mode);
 void imx6_set_int_mem_clk_lpm(bool enable);
 void imx6sl_set_wait_clk(bool enter);
 int imx_mmdc_get_ddr_type(void);
+int imx7ulp_set_lpm(enum ulp_cpu_pwr_mode mode);
 
 void imx_cpu_die(unsigned int cpu);
 int imx_cpu_kill(unsigned int cpu);

diff --git a/arch/arm/mach-imx/cpuidle-imx7ulp.c b/arch/arm/mach-imx/cpuidle-imx7ulp.c
new file mode 100644 (file)
index 0000000..ca86c96
--- /dev/null
+++ b/arch/arm/mach-imx/cpuidle-imx7ulp.c
@@ -0,0 +1,60 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2016 Freescale Semiconductor, Inc.
+ * Copyright 2017-2018 NXP
+ *   Anson Huang <Anson.Huang@nxp.com>
+ */
+
+#include <linux/cpuidle.h>
+#include <linux/module.h>
+#include <asm/cpuidle.h>
+
+#include "common.h"
+#include "cpuidle.h"
+
+static int imx7ulp_enter_wait(struct cpuidle_device *dev,
+                           struct cpuidle_driver *drv, int index)
+{
+       if (index == 1)
+               imx7ulp_set_lpm(ULP_PM_WAIT);
+       else
+               imx7ulp_set_lpm(ULP_PM_STOP);
+
+       cpu_do_idle();
+
+       imx7ulp_set_lpm(ULP_PM_RUN);
+
+       return index;
+}
+
+static struct cpuidle_driver imx7ulp_cpuidle_driver = {
+       .name = "imx7ulp_cpuidle",
+       .owner = THIS_MODULE,
+       .states = {
+               /* WFI */
+               ARM_CPUIDLE_WFI_STATE,
+               /* WAIT */
+               {
+                       .exit_latency = 50,
+                       .target_residency = 75,
+                       .enter = imx7ulp_enter_wait,
+                       .name = "WAIT",
+                       .desc = "PSTOP2",
+               },
+               /* STOP */
+               {
+                       .exit_latency = 100,
+                       .target_residency = 150,
+                       .enter = imx7ulp_enter_wait,
+                       .name = "STOP",
+                       .desc = "PSTOP1",
+               },
+       },
+       .state_count = 3,
+       .safe_state_index = 0,
+};
+
+int __init imx7ulp_cpuidle_init(void)
+{
+       return cpuidle_register(&imx7ulp_cpuidle_driver, NULL);
+}

diff --git a/arch/arm/mach-imx/cpuidle.h b/arch/arm/mach-imx/cpuidle.h
index f914012..7694c8f 100644 (file)
--- a/arch/arm/mach-imx/cpuidle.h
+++ b/arch/arm/mach-imx/cpuidle.h
@@ -15,6 +15,7 @@ extern int imx5_cpuidle_init(void);
 extern int imx6q_cpuidle_init(void);
 extern int imx6sl_cpuidle_init(void);
 extern int imx6sx_cpuidle_init(void);
+extern int imx7ulp_cpuidle_init(void);
 #else
 static inline int imx5_cpuidle_init(void)
 {
@@ -32,4 +33,8 @@ static inline int imx6sx_cpuidle_init(void)
 {
        return 0;
 }
+static inline int imx7ulp_cpuidle_init(void)
+{
+       return 0;
+}
 #endif

diff --git a/arch/arm/mach-imx/mach-imx7ulp.c b/arch/arm/mach-imx/mach-imx7ulp.c
index 33937eb..19c5b30 100644 (file)
--- a/arch/arm/mach-imx/mach-imx7ulp.c
+++ b/arch/arm/mach-imx/mach-imx7ulp.c
@@ -10,6 +10,7 @@
 #include <asm/mach/arch.h>
 
 #include "common.h"
+#include "cpuidle.h"
 #include "hardware.h"
 
 static void __init imx7ulp_init_machine(void)
@@ -25,7 +26,13 @@ static const char *const imx7ulp_dt_compat[] __initconst = {
        NULL,
 };
 
+static void __init imx7ulp_init_late(void)
+{
+       imx7ulp_cpuidle_init();
+}
+
 DT_MACHINE_START(IMX7ulp, "Freescale i.MX7ULP (Device Tree)")
        .init_machine   = imx7ulp_init_machine,
        .dt_compat      = imx7ulp_dt_compat,
+       .init_late      = imx7ulp_init_late,
 MACHINE_END

diff --git a/arch/arm/mach-imx/pm-imx7ulp.c b/arch/arm/mach-imx/pm-imx7ulp.c
index cf6a380..7b2f738 100644 (file)
--- a/arch/arm/mach-imx/pm-imx7ulp.c
+++ b/arch/arm/mach-imx/pm-imx7ulp.c
@@ -9,21 +9,60 @@
 #include <linux/of.h>
 #include <linux/of_address.h>
 
+#include "common.h"
+
 #define SMC_PMCTRL             0x10
 #define BP_PMCTRL_PSTOPO        16
 #define PSTOPO_PSTOP3          0x3
+#define PSTOPO_PSTOP2          0x2
+#define PSTOPO_PSTOP1          0x1
+#define BP_PMCTRL_RUNM         8
+#define RUNM_RUN               0
+#define BP_PMCTRL_STOPM                0
+#define STOPM_STOP             0
+
+#define BM_PMCTRL_PSTOPO       (3 << BP_PMCTRL_PSTOPO)
+#define BM_PMCTRL_RUNM         (3 << BP_PMCTRL_RUNM)
+#define BM_PMCTRL_STOPM                (7 << BP_PMCTRL_STOPM)
+
+static void __iomem *smc1_base;
+
+int imx7ulp_set_lpm(enum ulp_cpu_pwr_mode mode)
+{
+       u32 val = readl_relaxed(smc1_base + SMC_PMCTRL);
+
+       /* clear all */
+       val &= ~(BM_PMCTRL_RUNM | BM_PMCTRL_STOPM | BM_PMCTRL_PSTOPO);
+
+       switch (mode) {
+       case ULP_PM_RUN:
+               /* system/bus clock enabled */
+               val |= PSTOPO_PSTOP3 << BP_PMCTRL_PSTOPO;
+               break;
+       case ULP_PM_WAIT:
+               /* system clock disabled, bus clock enabled */
+               val |= PSTOPO_PSTOP2 << BP_PMCTRL_PSTOPO;
+               break;
+       case ULP_PM_STOP:
+               /* system/bus clock disabled */
+               val |= PSTOPO_PSTOP1 << BP_PMCTRL_PSTOPO;
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       writel_relaxed(val, smc1_base + SMC_PMCTRL);
+
+       return 0;
+}
 
 void __init imx7ulp_pm_init(void)
 {
        struct device_node *np;
-       void __iomem *smc1_base;
 
        np = of_find_compatible_node(NULL, NULL, "fsl,imx7ulp-smc1");
        smc1_base = of_iomap(np, 0);
        WARN_ON(!smc1_base);
 
-       /* Partial Stop mode 3 with system/bus clock enabled */
-       writel_relaxed(PSTOPO_PSTOP3 << BP_PMCTRL_PSTOPO,
-                      smc1_base + SMC_PMCTRL);
-       iounmap(smc1_base);
+       imx7ulp_set_lpm(ULP_PM_RUN);
 }