diff options
Diffstat (limited to 'drivers/cpuidle')
| -rw-r--r-- | drivers/cpuidle/Kconfig | 6 | ||||
| -rw-r--r-- | drivers/cpuidle/Makefile | 1 | ||||
| -rw-r--r-- | drivers/cpuidle/cpuidle-kirkwood.c | 106 |
3 files changed, 113 insertions, 0 deletions
diff --git a/drivers/cpuidle/Kconfig b/drivers/cpuidle/Kconfig index c4cc27e5c8a5..071e2c3eec4f 100644 --- a/drivers/cpuidle/Kconfig +++ b/drivers/cpuidle/Kconfig @@ -39,4 +39,10 @@ config CPU_IDLE_CALXEDA help Select this to enable cpuidle on Calxeda processors. +config CPU_IDLE_KIRKWOOD + bool "CPU Idle Driver for Kirkwood processors" + depends on ARCH_KIRKWOOD + help + Select this to enable cpuidle on Kirkwood processors. + endif diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile index 03ee87482c71..24c6e7d945ed 100644 --- a/drivers/cpuidle/Makefile +++ b/drivers/cpuidle/Makefile @@ -6,3 +6,4 @@ obj-y += cpuidle.o driver.o governor.o sysfs.o governors/ obj-$(CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED) += coupled.o obj-$(CONFIG_CPU_IDLE_CALXEDA) += cpuidle-calxeda.o +obj-$(CONFIG_CPU_IDLE_KIRKWOOD) += cpuidle-kirkwood.o diff --git a/drivers/cpuidle/cpuidle-kirkwood.c b/drivers/cpuidle/cpuidle-kirkwood.c new file mode 100644 index 000000000000..670aa1e55cd6 --- /dev/null +++ b/drivers/cpuidle/cpuidle-kirkwood.c @@ -0,0 +1,106 @@ +/* + * arch/arm/mach-kirkwood/cpuidle.c + * + * CPU idle Marvell Kirkwood SoCs + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + * + * The cpu idle uses wait-for-interrupt and DDR self refresh in order + * to implement two idle states - + * #1 wait-for-interrupt + * #2 wait-for-interrupt and DDR self refresh + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/platform_device.h> +#include <linux/cpuidle.h> +#include <linux/io.h> +#include <linux/export.h> +#include <asm/proc-fns.h> +#include <asm/cpuidle.h> + +#define KIRKWOOD_MAX_STATES 2 + +static void __iomem *ddr_operation_base; + +/* Actual code that puts the SoC in different idle states */ +static int kirkwood_enter_idle(struct cpuidle_device *dev, + struct cpuidle_driver *drv, + int index) +{ + writel(0x7, ddr_operation_base); + cpu_do_idle(); + + return index; +} + +static struct cpuidle_driver kirkwood_idle_driver = { + .name = "kirkwood_idle", + .owner = THIS_MODULE, + .en_core_tk_irqen = 1, + .states[0] = ARM_CPUIDLE_WFI_STATE, + .states[1] = { + .enter = kirkwood_enter_idle, + .exit_latency = 10, + .target_residency = 100000, + .flags = CPUIDLE_FLAG_TIME_VALID, + .name = "DDR SR", + .desc = "WFI and DDR Self Refresh", + }, + .state_count = KIRKWOOD_MAX_STATES, +}; +static struct cpuidle_device *device; + +static DEFINE_PER_CPU(struct cpuidle_device, kirkwood_cpuidle_device); + +/* Initialize CPU idle by registering the idle states */ +static int kirkwood_cpuidle_probe(struct platform_device *pdev) +{ + struct resource *res; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (res == NULL) + return -EINVAL; + + ddr_operation_base = devm_request_and_ioremap(&pdev->dev, res); + if (!ddr_operation_base) + return -EADDRNOTAVAIL; + + device = &per_cpu(kirkwood_cpuidle_device, smp_processor_id()); + device->state_count = KIRKWOOD_MAX_STATES; + + cpuidle_register_driver(&kirkwood_idle_driver); + if (cpuidle_register_device(device)) { + pr_err("kirkwood_init_cpuidle: Failed registering\n"); + return -EIO; + } + return 0; +} + +int kirkwood_cpuidle_remove(struct platform_device *pdev) +{ + cpuidle_unregister_device(device); + cpuidle_unregister_driver(&kirkwood_idle_driver); + + return 0; +} + +static struct platform_driver kirkwood_cpuidle_driver = { + .probe = kirkwood_cpuidle_probe, + .remove = kirkwood_cpuidle_remove, + .driver = { + .name = "kirkwood_cpuidle", + .owner = THIS_MODULE, + }, +}; + +module_platform_driver(kirkwood_cpuidle_driver); + +MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>"); +MODULE_DESCRIPTION("Kirkwood cpu idle driver"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:kirkwood-cpuidle"); |