diff options
| -rw-r--r-- | arch/arm/boot/dts/highbank.dts | 10 | ||||
| -rw-r--r-- | arch/arm/mach-highbank/Kconfig | 2 | ||||
| -rw-r--r-- | drivers/cpufreq/Kconfig.arm | 15 | ||||
| -rw-r--r-- | drivers/cpufreq/Makefile | 3 | ||||
| -rw-r--r-- | drivers/cpufreq/cpufreq-cpu0.c | 6 | ||||
| -rw-r--r-- | drivers/cpufreq/highbank-cpufreq.c | 115 |
6 files changed, 149 insertions, 2 deletions
diff --git a/arch/arm/boot/dts/highbank.dts b/arch/arm/boot/dts/highbank.dts index 5927a8df5625..6aad34ad9517 100644 --- a/arch/arm/boot/dts/highbank.dts +++ b/arch/arm/boot/dts/highbank.dts @@ -37,6 +37,16 @@ next-level-cache = <&L2>; clocks = <&a9pll>; clock-names = "cpu"; + operating-points = < + /* kHz ignored */ + 1300000 1000000 + 1200000 1000000 + 1100000 1000000 + 800000 1000000 + 400000 1000000 + 200000 1000000 + >; + clock-latency = <100000>; }; cpu@901 { diff --git a/arch/arm/mach-highbank/Kconfig b/arch/arm/mach-highbank/Kconfig index 2388085beaa2..44b12f9c1584 100644 --- a/arch/arm/mach-highbank/Kconfig +++ b/arch/arm/mach-highbank/Kconfig @@ -1,5 +1,7 @@ config ARCH_HIGHBANK bool "Calxeda ECX-1000/2000 (Highbank/Midway)" if ARCH_MULTI_V7 + select ARCH_HAS_CPUFREQ + select ARCH_HAS_OPP select ARCH_WANT_OPTIONAL_GPIOLIB select ARM_AMBA select ARM_GIC diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm index a0b3661d90b0..ffe55b8a98cc 100644 --- a/drivers/cpufreq/Kconfig.arm +++ b/drivers/cpufreq/Kconfig.arm @@ -83,3 +83,18 @@ config ARM_SPEAR_CPUFREQ default y help This adds the CPUFreq driver support for SPEAr SOCs. + +config ARM_HIGHBANK_CPUFREQ + tristate "Calxeda Highbank-based" + depends on ARCH_HIGHBANK + select CPU_FREQ_TABLE + select GENERIC_CPUFREQ_CPU0 + select PM_OPP + select REGULATOR + + default m + help + This adds the CPUFreq driver for Calxeda Highbank SoC + based boards. + + If in doubt, say N. diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile index 24d4a63fd6cf..e2a5da77370f 100644 --- a/drivers/cpufreq/Makefile +++ b/drivers/cpufreq/Makefile @@ -51,8 +51,9 @@ obj-$(CONFIG_ARM_EXYNOS_CPUFREQ) += exynos-cpufreq.o obj-$(CONFIG_ARM_EXYNOS4210_CPUFREQ) += exynos4210-cpufreq.o obj-$(CONFIG_ARM_EXYNOS4X12_CPUFREQ) += exynos4x12-cpufreq.o obj-$(CONFIG_ARM_EXYNOS5250_CPUFREQ) += exynos5250-cpufreq.o -obj-$(CONFIG_ARM_OMAP2PLUS_CPUFREQ) += omap-cpufreq.o +obj-$(CONFIG_ARM_OMAP2PLUS_CPUFREQ) += omap-cpufreq.o obj-$(CONFIG_ARM_SPEAR_CPUFREQ) += spear-cpufreq.o +obj-$(CONFIG_ARM_HIGHBANK_CPUFREQ) += highbank-cpufreq.o ################################################################################## # PowerPC platform drivers diff --git a/drivers/cpufreq/cpufreq-cpu0.c b/drivers/cpufreq/cpufreq-cpu0.c index debc5a7c8db6..38ae178ce4ef 100644 --- a/drivers/cpufreq/cpufreq-cpu0.c +++ b/drivers/cpufreq/cpufreq-cpu0.c @@ -182,7 +182,11 @@ static int cpu0_cpufreq_driver_init(void) struct device_node *np; int ret; - np = of_find_node_by_path("/cpus/cpu@0"); + for_each_child_of_node(of_find_node_by_path("/cpus"), np) { + if (of_get_property(np, "operating-points", NULL)) + break; + } + if (!np) { pr_err("failed to find cpu0 node\n"); return -ENOENT; diff --git a/drivers/cpufreq/highbank-cpufreq.c b/drivers/cpufreq/highbank-cpufreq.c new file mode 100644 index 000000000000..53f25e5aa6b7 --- /dev/null +++ b/drivers/cpufreq/highbank-cpufreq.c @@ -0,0 +1,115 @@ +/* + * Copyright (C) 2012 Calxeda, 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. + * + * This driver provides the clk notifier callbacks that are used when + * the cpufreq-cpu0 driver changes to frequency to alert the highbank + * EnergyCore Management Engine (ECME) about the need to change + * voltage. The ECME interfaces with the actual voltage regulators. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/clk.h> +#include <linux/cpu.h> +#include <linux/err.h> +#include <linux/of.h> +#include <linux/mailbox.h> + +#define HB_CPUFREQ_CHANGE_NOTE 0x80000001 +#define HB_CPUFREQ_IPC_LEN 7 +#define HB_CPUFREQ_VOLT_RETRIES 15 + +static int hb_voltage_change(unsigned int freq) +{ + int i; + u32 msg[HB_CPUFREQ_IPC_LEN]; + + msg[0] = HB_CPUFREQ_CHANGE_NOTE; + msg[1] = freq / 1000000; + for (i = 2; i < HB_CPUFREQ_IPC_LEN; i++) + msg[i] = 0; + + return pl320_ipc_transmit(msg); +} + +static int hb_cpufreq_clk_notify(struct notifier_block *nb, + unsigned long action, void *hclk) +{ + struct clk_notifier_data *clk_data = hclk; + int i = 0; + + if (action == PRE_RATE_CHANGE) { + if (clk_data->new_rate > clk_data->old_rate) + while (hb_voltage_change(clk_data->new_rate)) + if (i++ > HB_CPUFREQ_VOLT_RETRIES) + return NOTIFY_BAD; + } else if (action == POST_RATE_CHANGE) { + if (clk_data->new_rate < clk_data->old_rate) + while (hb_voltage_change(clk_data->new_rate)) + if (i++ > HB_CPUFREQ_VOLT_RETRIES) + return NOTIFY_BAD; + } + + return NOTIFY_DONE; +} + +static struct notifier_block hb_cpufreq_clk_nb = { + .notifier_call = hb_cpufreq_clk_notify, +}; + +static int hb_cpufreq_driver_init(void) +{ + struct device *cpu_dev; + struct clk *cpu_clk; + struct device_node *np; + int ret; + + if (!of_machine_is_compatible("calxeda,highbank")) + return -ENODEV; + + for_each_child_of_node(of_find_node_by_path("/cpus"), np) + if (of_get_property(np, "operating-points", NULL)) + break; + + if (!np) { + pr_err("failed to find highbank cpufreq node\n"); + return -ENOENT; + } + + cpu_dev = get_cpu_device(0); + if (!cpu_dev) { + pr_err("failed to get highbank cpufreq device\n"); + ret = -ENODEV; + goto out_put_node; + } + + cpu_dev->of_node = np; + + cpu_clk = clk_get(cpu_dev, NULL); + if (IS_ERR(cpu_clk)) { + ret = PTR_ERR(cpu_clk); + pr_err("failed to get cpu0 clock: %d\n", ret); + goto out_put_node; + } + + ret = clk_notifier_register(cpu_clk, &hb_cpufreq_clk_nb); + if (ret) { + pr_err("failed to register clk notifier: %d\n", ret); + goto out_put_node; + } + +out_put_node: + of_node_put(np); + return ret; +} +module_init(hb_cpufreq_driver_init); + +MODULE_AUTHOR("Mark Langsdorf <mark.langsdorf@calxeda.com>"); +MODULE_DESCRIPTION("Calxeda Highbank cpufreq driver"); +MODULE_LICENSE("GPL"); |