From 6baf6ee534c56e754ca854176be0073bc2c9e6a4 Mon Sep 17 00:00:00 2001 From: Kevin Hilman Date: Tue, 12 Aug 2014 17:11:05 -0700 Subject: cpuidle: big.LITTLE: add Exynos5800 compatible string Exynos 5800 is big.LITTLE SoC compatible with the 5420. Add the compatible string so this driver works on the 5800. Tested on exynos5800-peach-pi (aka Samsung Chromebook2) Signed-off-by: Kevin Hilman Signed-off-by: Daniel Lezcano --- drivers/cpuidle/cpuidle-big_little.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers') diff --git a/drivers/cpuidle/cpuidle-big_little.c b/drivers/cpuidle/cpuidle-big_little.c index ef94c3b81f18..9342a94f417f 100644 --- a/drivers/cpuidle/cpuidle-big_little.c +++ b/drivers/cpuidle/cpuidle-big_little.c @@ -159,6 +159,7 @@ static int __init bl_idle_driver_init(struct cpuidle_driver *drv, int part_id) static const struct of_device_id compatible_machine_match[] = { { .compatible = "arm,vexpress,v2p-ca15_a7" }, { .compatible = "samsung,exynos5420" }, + { .compatible = "samsung,exynos5800" }, {}, }; -- cgit v1.2.3 From 9f14da345599c14b329cf5ac9499ad322056dd32 Mon Sep 17 00:00:00 2001 From: Lorenzo Pieralisi Date: Fri, 14 Feb 2014 14:28:39 +0000 Subject: drivers: cpuidle: implement DT based idle states infrastructure On most common ARM systems, the low-power states a CPU can be put into are not discoverable in HW and require device tree bindings to describe power down suspend operations and idle states parameters. In order to enable DT based idle states and configure idle drivers, this patch implements the bulk infrastructure required to parse the device tree idle states bindings and initialize the corresponding CPUidle driver states data. The parsing API accepts a start index that defines the first idle state that should be initialized by the parsing code in order to give new and legacy driver flexibility over which states should be parsed using the new DT mechanism. The idle states node(s) is obtained from the phandle list of the first cpu in the driver cpumask; the kernel checks that the idle state node phandle is the same for all CPUs in the driver cpumask before declaring the idle state as valid and start parsing its content. The idle state enter function pointer is initialized through DT match structures passed in by the CPUidle driver, so that ARM legacy code can cope with platform specific idle entry method based on compatible string matching and the code used to initialize the enter function pointer can be moved to the DT generic layer. Acked-by: Catalin Marinas Acked-by: Daniel Lezcano Signed-off-by: Lorenzo Pieralisi Signed-off-by: Daniel Lezcano --- drivers/cpuidle/Kconfig | 3 + drivers/cpuidle/Makefile | 1 + drivers/cpuidle/dt_idle_states.c | 213 +++++++++++++++++++++++++++++++++++++++ drivers/cpuidle/dt_idle_states.h | 7 ++ 4 files changed, 224 insertions(+) create mode 100644 drivers/cpuidle/dt_idle_states.c create mode 100644 drivers/cpuidle/dt_idle_states.h (limited to 'drivers') diff --git a/drivers/cpuidle/Kconfig b/drivers/cpuidle/Kconfig index 32748c36c477..8deb934c6356 100644 --- a/drivers/cpuidle/Kconfig +++ b/drivers/cpuidle/Kconfig @@ -25,6 +25,9 @@ config CPU_IDLE_GOV_MENU bool "Menu governor (for tickless system)" default y +config DT_IDLE_STATES + bool + menu "ARM CPU Idle Drivers" depends on ARM source "drivers/cpuidle/Kconfig.arm" diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile index 11edb31c55e9..002b65336ba9 100644 --- a/drivers/cpuidle/Makefile +++ b/drivers/cpuidle/Makefile @@ -4,6 +4,7 @@ obj-y += cpuidle.o driver.o governor.o sysfs.o governors/ obj-$(CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED) += coupled.o +obj-$(CONFIG_DT_IDLE_STATES) += dt_idle_states.o ################################################################################## # ARM SoC drivers diff --git a/drivers/cpuidle/dt_idle_states.c b/drivers/cpuidle/dt_idle_states.c new file mode 100644 index 000000000000..52f4d11bbf3f --- /dev/null +++ b/drivers/cpuidle/dt_idle_states.c @@ -0,0 +1,213 @@ +/* + * DT idle states parsing code. + * + * Copyright (C) 2014 ARM Ltd. + * Author: Lorenzo Pieralisi + * + * 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. + */ + +#define pr_fmt(fmt) "DT idle-states: " fmt + +#include +#include +#include +#include +#include +#include +#include + +#include "dt_idle_states.h" + +static int init_state_node(struct cpuidle_state *idle_state, + const struct of_device_id *matches, + struct device_node *state_node) +{ + int err; + const struct of_device_id *match_id; + + match_id = of_match_node(matches, state_node); + if (!match_id) + return -ENODEV; + /* + * CPUidle drivers are expected to initialize the const void *data + * pointer of the passed in struct of_device_id array to the idle + * state enter function. + */ + idle_state->enter = match_id->data; + + err = of_property_read_u32(state_node, "wakeup-latency-us", + &idle_state->exit_latency); + if (err) { + u32 entry_latency, exit_latency; + + err = of_property_read_u32(state_node, "entry-latency-us", + &entry_latency); + if (err) { + pr_debug(" * %s missing entry-latency-us property\n", + state_node->full_name); + return -EINVAL; + } + + err = of_property_read_u32(state_node, "exit-latency-us", + &exit_latency); + if (err) { + pr_debug(" * %s missing exit-latency-us property\n", + state_node->full_name); + return -EINVAL; + } + /* + * If wakeup-latency-us is missing, default to entry+exit + * latencies as defined in idle states bindings + */ + idle_state->exit_latency = entry_latency + exit_latency; + } + + err = of_property_read_u32(state_node, "min-residency-us", + &idle_state->target_residency); + if (err) { + pr_debug(" * %s missing min-residency-us property\n", + state_node->full_name); + return -EINVAL; + } + + idle_state->flags = CPUIDLE_FLAG_TIME_VALID; + if (of_property_read_bool(state_node, "local-timer-stop")) + idle_state->flags |= CPUIDLE_FLAG_TIMER_STOP; + /* + * TODO: + * replace with kstrdup and pointer assignment when name + * and desc become string pointers + */ + strncpy(idle_state->name, state_node->name, CPUIDLE_NAME_LEN - 1); + strncpy(idle_state->desc, state_node->name, CPUIDLE_DESC_LEN - 1); + return 0; +} + +/* + * Check that the idle state is uniform across all CPUs in the CPUidle driver + * cpumask + */ +static bool idle_state_valid(struct device_node *state_node, unsigned int idx, + const cpumask_t *cpumask) +{ + int cpu; + struct device_node *cpu_node, *curr_state_node; + bool valid = true; + + /* + * Compare idle state phandles for index idx on all CPUs in the + * CPUidle driver cpumask. Start from next logical cpu following + * cpumask_first(cpumask) since that's the CPU state_node was + * retrieved from. If a mismatch is found bail out straight + * away since we certainly hit a firmware misconfiguration. + */ + for (cpu = cpumask_next(cpumask_first(cpumask), cpumask); + cpu < nr_cpu_ids; cpu = cpumask_next(cpu, cpumask)) { + cpu_node = of_cpu_device_node_get(cpu); + curr_state_node = of_parse_phandle(cpu_node, "cpu-idle-states", + idx); + if (state_node != curr_state_node) + valid = false; + + of_node_put(curr_state_node); + of_node_put(cpu_node); + if (!valid) + break; + } + + return valid; +} + +/** + * dt_init_idle_driver() - Parse the DT idle states and initialize the + * idle driver states array + * @drv: Pointer to CPU idle driver to be initialized + * @matches: Array of of_device_id match structures to search in for + * compatible idle state nodes. The data pointer for each valid + * struct of_device_id entry in the matches array must point to + * a function with the following signature, that corresponds to + * the CPUidle state enter function signature: + * + * int (*)(struct cpuidle_device *dev, + * struct cpuidle_driver *drv, + * int index); + * + * @start_idx: First idle state index to be initialized + * + * If DT idle states are detected and are valid the state count and states + * array entries in the cpuidle driver are initialized accordingly starting + * from index start_idx. + * + * Return: number of valid DT idle states parsed, <0 on failure + */ +int dt_init_idle_driver(struct cpuidle_driver *drv, + const struct of_device_id *matches, + unsigned int start_idx) +{ + struct cpuidle_state *idle_state; + struct device_node *state_node, *cpu_node; + int i, err = 0; + const cpumask_t *cpumask; + unsigned int state_idx = start_idx; + + if (state_idx >= CPUIDLE_STATE_MAX) + return -EINVAL; + /* + * We get the idle states for the first logical cpu in the + * driver mask (or cpu_possible_mask if the driver cpumask is not set) + * and we check through idle_state_valid() if they are uniform + * across CPUs, otherwise we hit a firmware misconfiguration. + */ + cpumask = drv->cpumask ? : cpu_possible_mask; + cpu_node = of_cpu_device_node_get(cpumask_first(cpumask)); + + for (i = 0; ; i++) { + state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i); + if (!state_node) + break; + + if (!idle_state_valid(state_node, i, cpumask)) { + pr_warn("%s idle state not valid, bailing out\n", + state_node->full_name); + err = -EINVAL; + break; + } + + if (state_idx == CPUIDLE_STATE_MAX) { + pr_warn("State index reached static CPU idle driver states array size\n"); + break; + } + + idle_state = &drv->states[state_idx++]; + err = init_state_node(idle_state, matches, state_node); + if (err) { + pr_err("Parsing idle state node %s failed with err %d\n", + state_node->full_name, err); + err = -EINVAL; + break; + } + of_node_put(state_node); + } + + of_node_put(state_node); + of_node_put(cpu_node); + if (err) + return err; + /* + * Update the driver state count only if some valid DT idle states + * were detected + */ + if (i) + drv->state_count = state_idx; + + /* + * Return the number of present and valid DT idle states, which can + * also be 0 on platforms with missing DT idle states or legacy DT + * configuration predating the DT idle states bindings. + */ + return i; +} +EXPORT_SYMBOL_GPL(dt_init_idle_driver); diff --git a/drivers/cpuidle/dt_idle_states.h b/drivers/cpuidle/dt_idle_states.h new file mode 100644 index 000000000000..4818134bc65b --- /dev/null +++ b/drivers/cpuidle/dt_idle_states.h @@ -0,0 +1,7 @@ +#ifndef __DT_IDLE_STATES +#define __DT_IDLE_STATES + +int dt_init_idle_driver(struct cpuidle_driver *drv, + const struct of_device_id *matches, + unsigned int start_idx); +#endif -- cgit v1.2.3 From 3299b63de384159579143d4abdfb94013e0b5470 Mon Sep 17 00:00:00 2001 From: Lorenzo Pieralisi Date: Fri, 28 Feb 2014 13:03:44 +0000 Subject: drivers: cpuidle: CPU idle ARM64 driver This patch implements a generic CPU idle driver for ARM64 machines. It relies on the DT idle states infrastructure to initialize idle states count and respective parameters. Current code assumes the driver is managing idle states on all possible CPUs but can be easily generalized to support heterogenous systems and build cpumasks at runtime using MIDRs or DT cpu nodes compatible properties. The driver relies on the arm64 CPU operations to call the idle initialization hook used to parse and save suspend back-end specific idle states information upon probing. Idle state index 0 is always initialized as a simple wfi state, ie always considered present and functional on all ARM64 platforms. Idle state indices higher than 0 trigger idle state entry by calling the cpu_suspend function, that triggers the suspend operation through the CPU operations suspend back-end hook. cpu_suspend passes the idle state index as a parameter so that the CPU operations suspend back-end can retrieve the required idle state data by using the idle state index to execute a look-up on its internal data structures. Reviewed-by: Ashwin Chaugule Reviewed-by: Catalin Marinas Signed-off-by: Lorenzo Pieralisi Signed-off-by: Daniel Lezcano --- drivers/cpuidle/Kconfig | 5 ++ drivers/cpuidle/Kconfig.arm64 | 14 +++++ drivers/cpuidle/Makefile | 4 ++ drivers/cpuidle/cpuidle-arm64.c | 133 ++++++++++++++++++++++++++++++++++++++++ 4 files changed, 156 insertions(+) create mode 100644 drivers/cpuidle/Kconfig.arm64 create mode 100644 drivers/cpuidle/cpuidle-arm64.c (limited to 'drivers') diff --git a/drivers/cpuidle/Kconfig b/drivers/cpuidle/Kconfig index 8deb934c6356..c5029c1209b4 100644 --- a/drivers/cpuidle/Kconfig +++ b/drivers/cpuidle/Kconfig @@ -33,6 +33,11 @@ depends on ARM source "drivers/cpuidle/Kconfig.arm" endmenu +menu "ARM64 CPU Idle Drivers" +depends on ARM64 +source "drivers/cpuidle/Kconfig.arm64" +endmenu + menu "MIPS CPU Idle Drivers" depends on MIPS source "drivers/cpuidle/Kconfig.mips" diff --git a/drivers/cpuidle/Kconfig.arm64 b/drivers/cpuidle/Kconfig.arm64 new file mode 100644 index 000000000000..d0a08ed1b2ee --- /dev/null +++ b/drivers/cpuidle/Kconfig.arm64 @@ -0,0 +1,14 @@ +# +# ARM64 CPU Idle drivers +# + +config ARM64_CPUIDLE + bool "Generic ARM64 CPU idle Driver" + select ARM64_CPU_SUSPEND + select DT_IDLE_STATES + help + Select this to enable generic cpuidle driver for ARM64. + It provides a generic idle driver whose idle states are configured + at run-time through DT nodes. The CPUidle suspend backend is + initialized by calling the CPU operations init idle hook + provided by architecture code. diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile index 002b65336ba9..4d177b916f75 100644 --- a/drivers/cpuidle/Makefile +++ b/drivers/cpuidle/Makefile @@ -22,6 +22,10 @@ obj-$(CONFIG_ARM_EXYNOS_CPUIDLE) += cpuidle-exynos.o # MIPS drivers obj-$(CONFIG_MIPS_CPS_CPUIDLE) += cpuidle-cps.o +############################################################################### +# ARM64 drivers +obj-$(CONFIG_ARM64_CPUIDLE) += cpuidle-arm64.o + ############################################################################### # POWERPC drivers obj-$(CONFIG_PSERIES_CPUIDLE) += cpuidle-pseries.o diff --git a/drivers/cpuidle/cpuidle-arm64.c b/drivers/cpuidle/cpuidle-arm64.c new file mode 100644 index 000000000000..50997ea942fc --- /dev/null +++ b/drivers/cpuidle/cpuidle-arm64.c @@ -0,0 +1,133 @@ +/* + * ARM64 generic CPU idle driver. + * + * Copyright (C) 2014 ARM Ltd. + * Author: Lorenzo Pieralisi + * + * 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. + */ + +#define pr_fmt(fmt) "CPUidle arm64: " fmt + +#include +#include +#include +#include +#include +#include + +#include +#include + +#include "dt_idle_states.h" + +/* + * arm64_enter_idle_state - Programs CPU to enter the specified state + * + * dev: cpuidle device + * drv: cpuidle driver + * idx: state index + * + * Called from the CPUidle framework to program the device to the + * specified target state selected by the governor. + */ +static int arm64_enter_idle_state(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int idx) +{ + int ret; + + if (!idx) { + cpu_do_idle(); + return idx; + } + + ret = cpu_pm_enter(); + if (!ret) { + /* + * Pass idle state index to cpu_suspend which in turn will + * call the CPU ops suspend protocol with idle index as a + * parameter. + */ + ret = cpu_suspend(idx); + + cpu_pm_exit(); + } + + return ret ? -1 : idx; +} + +static struct cpuidle_driver arm64_idle_driver = { + .name = "arm64_idle", + .owner = THIS_MODULE, + /* + * State at index 0 is standby wfi and considered standard + * on all ARM platforms. If in some platforms simple wfi + * can't be used as "state 0", DT bindings must be implemented + * to work around this issue and allow installing a special + * handler for idle state index 0. + */ + .states[0] = { + .enter = arm64_enter_idle_state, + .exit_latency = 1, + .target_residency = 1, + .power_usage = UINT_MAX, + .flags = CPUIDLE_FLAG_TIME_VALID, + .name = "WFI", + .desc = "ARM64 WFI", + } +}; + +static const struct of_device_id arm64_idle_state_match[] __initconst = { + { .compatible = "arm,idle-state", + .data = arm64_enter_idle_state }, + { }, +}; + +/* + * arm64_idle_init + * + * Registers the arm64 specific cpuidle driver with the cpuidle + * framework. It relies on core code to parse the idle states + * and initialize them using driver data structures accordingly. + */ +static int __init arm64_idle_init(void) +{ + int cpu, ret; + struct cpuidle_driver *drv = &arm64_idle_driver; + + /* + * Initialize idle states data, starting at index 1. + * This driver is DT only, if no DT idle states are detected (ret == 0) + * let the driver initialization fail accordingly since there is no + * reason to initialize the idle driver if only wfi is supported. + */ + ret = dt_init_idle_driver(drv, arm64_idle_state_match, 1); + if (ret <= 0) { + if (ret) + pr_err("failed to initialize idle states\n"); + return ret ? : -ENODEV; + } + + /* + * Call arch CPU operations in order to initialize + * idle states suspend back-end specific data + */ + for_each_possible_cpu(cpu) { + ret = cpu_init_idle(cpu); + if (ret) { + pr_err("CPU %d failed to init idle CPU ops\n", cpu); + return ret; + } + } + + ret = cpuidle_register(drv, NULL); + if (ret) { + pr_err("failed to register cpuidle driver\n"); + return ret; + } + + return 0; +} +device_initcall(arm64_idle_init); -- cgit v1.2.3 From d2e5c871ed8a250f7ee1fe34dd52ed5757363fba Mon Sep 17 00:00:00 2001 From: Lorenzo Pieralisi Date: Tue, 24 Jun 2014 16:20:28 +0100 Subject: drivers: cpuidle: initialize big.LITTLE driver through DT With the introduction of DT based idle states, CPUidle drivers for ARM can now initialize idle states data through properties in the device tree. This patch adds code to the big.LITTLE CPUidle driver to dynamically initialize idle states data through the updated device tree source file. Cc: Chander Kashyap Acked-by: Catalin Marinas Acked-by: Daniel Lezcano Signed-off-by: Lorenzo Pieralisi Signed-off-by: Daniel Lezcano --- arch/arm/boot/dts/vexpress-v2p-ca15_a7.dts | 23 +++++++++++++++++++++++ drivers/cpuidle/Kconfig.arm | 1 + drivers/cpuidle/cpuidle-big_little.c | 19 +++++++++++++++++++ 3 files changed, 43 insertions(+) (limited to 'drivers') diff --git a/arch/arm/boot/dts/vexpress-v2p-ca15_a7.dts b/arch/arm/boot/dts/vexpress-v2p-ca15_a7.dts index a25c262326dc..322fd1519b09 100644 --- a/arch/arm/boot/dts/vexpress-v2p-ca15_a7.dts +++ b/arch/arm/boot/dts/vexpress-v2p-ca15_a7.dts @@ -38,6 +38,7 @@ compatible = "arm,cortex-a15"; reg = <0>; cci-control-port = <&cci_control1>; + cpu-idle-states = <&CLUSTER_SLEEP_BIG>; }; cpu1: cpu@1 { @@ -45,6 +46,7 @@ compatible = "arm,cortex-a15"; reg = <1>; cci-control-port = <&cci_control1>; + cpu-idle-states = <&CLUSTER_SLEEP_BIG>; }; cpu2: cpu@2 { @@ -52,6 +54,7 @@ compatible = "arm,cortex-a7"; reg = <0x100>; cci-control-port = <&cci_control2>; + cpu-idle-states = <&CLUSTER_SLEEP_LITTLE>; }; cpu3: cpu@3 { @@ -59,6 +62,7 @@ compatible = "arm,cortex-a7"; reg = <0x101>; cci-control-port = <&cci_control2>; + cpu-idle-states = <&CLUSTER_SLEEP_LITTLE>; }; cpu4: cpu@4 { @@ -66,6 +70,25 @@ compatible = "arm,cortex-a7"; reg = <0x102>; cci-control-port = <&cci_control2>; + cpu-idle-states = <&CLUSTER_SLEEP_LITTLE>; + }; + + idle-states { + CLUSTER_SLEEP_BIG: cluster-sleep-big { + compatible = "arm,idle-state"; + local-timer-stop; + entry-latency-us = <1000>; + exit-latency-us = <700>; + min-residency-us = <2000>; + }; + + CLUSTER_SLEEP_LITTLE: cluster-sleep-little { + compatible = "arm,idle-state"; + local-timer-stop; + entry-latency-us = <1000>; + exit-latency-us = <500>; + min-residency-us = <2500>; + }; }; }; diff --git a/drivers/cpuidle/Kconfig.arm b/drivers/cpuidle/Kconfig.arm index 38cff69ffe06..e339c7f2c2b7 100644 --- a/drivers/cpuidle/Kconfig.arm +++ b/drivers/cpuidle/Kconfig.arm @@ -7,6 +7,7 @@ config ARM_BIG_LITTLE_CPUIDLE depends on MCPM select ARM_CPU_SUSPEND select CPU_IDLE_MULTIPLE_DRIVERS + select DT_IDLE_STATES help Select this option to enable CPU idle driver for big.LITTLE based ARM systems. Driver manages CPUs coordination through MCPM and diff --git a/drivers/cpuidle/cpuidle-big_little.c b/drivers/cpuidle/cpuidle-big_little.c index 9342a94f417f..fbc00a1d3c48 100644 --- a/drivers/cpuidle/cpuidle-big_little.c +++ b/drivers/cpuidle/cpuidle-big_little.c @@ -24,6 +24,8 @@ #include #include +#include "dt_idle_states.h" + static int bl_enter_powerdown(struct cpuidle_device *dev, struct cpuidle_driver *drv, int idx); @@ -73,6 +75,12 @@ static struct cpuidle_driver bl_idle_little_driver = { .state_count = 2, }; +static const struct of_device_id bl_idle_state_match[] __initconst = { + { .compatible = "arm,idle-state", + .data = bl_enter_powerdown }, + { }, +}; + static struct cpuidle_driver bl_idle_big_driver = { .name = "big_idle", .owner = THIS_MODULE, @@ -191,6 +199,17 @@ static int __init bl_idle_init(void) if (ret) goto out_uninit_little; + /* Start at index 1, index 0 standard WFI */ + ret = dt_init_idle_driver(&bl_idle_big_driver, bl_idle_state_match, 1); + if (ret < 0) + goto out_uninit_big; + + /* Start at index 1, index 0 standard WFI */ + ret = dt_init_idle_driver(&bl_idle_little_driver, + bl_idle_state_match, 1); + if (ret < 0) + goto out_uninit_big; + ret = cpuidle_register(&bl_idle_little_driver, NULL); if (ret) goto out_uninit_big; -- cgit v1.2.3