| Message ID | 1354631642-30433-7-git-send-email-mark.langsdorf@calxeda.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
On Tue, Dec 04, 2012 at 08:34:02AM -0600, Mark Langsdorf wrote: > Highbank processors depend on the external ECME to perform voltage > management based on a requested frequency. Communication between the > A9 cores and the ECME happens over the pl320 IPC channel. > > Signed-off-by: Mark Langsdorf <mark.langsdorf@calxeda.com> > Cc: shawn.guo@linaro.org > Cc: mturquette@ti.com > --- > Changes from v6 > Removed devicetree bindings documentation. > Restructured driver to use clk notifications. > Core driver logic is now cpufreq-clk0. Great. It saves some codes :) > Changes from v5 > Changed ipc_transmit() to pl320_ipc_transmit(). > Changes from v4 > Removed erroneous changes to arch/arm/Kconfig. > Removed unnecessary changes to drivers/cpufreq/Kconfig.arm > Alphabetized additions to arch/arm/mach-highbank/Kconfig > Changed ipc call and header to match new ipc location in > drivers/mailbox. > Changes from v3 > None. > Changes from v2 > Changed transition latency binding in code to match documentation. > Changes from v1 > Added highbank specific Kconfig changes. > > arch/arm/boot/dts/highbank.dts | 10 ++++ > arch/arm/mach-highbank/Kconfig | 2 + > drivers/cpufreq/Kconfig.arm | 16 ++++++ > drivers/cpufreq/Makefile | 1 + > drivers/cpufreq/highbank-cpufreq.c | 106 +++++++++++++++++++++++++++++++++++++ > 5 files changed, 135 insertions(+) > create mode 100644 drivers/cpufreq/highbank-cpufreq.c > > diff --git a/arch/arm/boot/dts/highbank.dts b/arch/arm/boot/dts/highbank.dts > index 0c6fc34..7c4c27d 100644 > --- a/arch/arm/boot/dts/highbank.dts > +++ b/arch/arm/boot/dts/highbank.dts > @@ -36,6 +36,16 @@ > 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@1 { > diff --git a/arch/arm/mach-highbank/Kconfig b/arch/arm/mach-highbank/Kconfig > index 2896881..b7862da 100644 > --- a/arch/arm/mach-highbank/Kconfig > +++ b/arch/arm/mach-highbank/Kconfig > @@ -1,5 +1,7 @@ > config ARCH_HIGHBANK > bool "Calxeda ECX-1000 (Highbank)" 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 5961e64..7aaac9f 100644 > --- a/drivers/cpufreq/Kconfig.arm > +++ b/drivers/cpufreq/Kconfig.arm > @@ -76,3 +76,19 @@ config ARM_EXYNOS5250_CPUFREQ > help > This adds the CPUFreq driver for Samsung EXYNOS5250 > SoC. > + > +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 1bc90e1..9e8f12a 100644 > --- a/drivers/cpufreq/Makefile > +++ b/drivers/cpufreq/Makefile > @@ -50,6 +50,7 @@ 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_HIGHBANK_CPUFREQ) += highbank-cpufreq.o > > ################################################################################## > # PowerPC platform drivers > diff --git a/drivers/cpufreq/highbank-cpufreq.c b/drivers/cpufreq/highbank-cpufreq.c > new file mode 100644 > index 0000000..25ef437 > --- /dev/null > +++ b/drivers/cpufreq/highbank-cpufreq.c > @@ -0,0 +1,106 @@ > +/* > + * Copyright (C) 2012 Calxeda, Inc. > + * > + * derived from cpufreq-cpu0 by Freescale Semiconductor It's not any more, right? > + * > + * 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) 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/opp.h> Do you need this header? > +#include <linux/slab.h> > +#include <linux/mailbox.h> > + > +#define HB_CPUFREQ_CHANGE_NOTE 0x80000001 > + > +static struct device *cpu_dev; > +static struct clk *cpu_clk; These two now can be local variables hb_cpufreq_driver_init(). > + > +static int hb_voltage_change(unsigned int freq) > +{ > + int i; > + u32 msg[7]; > + > + msg[0] = HB_CPUFREQ_CHANGE_NOTE; > + msg[1] = freq / 1000000; > + for (i = 2; i < 7; 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++ > 15) > + return NOTIFY_STOP; > + } else if (action == POST_RATE_CHANGE) Add a {} pair for else block or remove {} for if? > + if (clk_data->new_rate < clk_data->old_rate) > + while (hb_voltage_change(clk_data->new_rate)) > + if (i++ > 15) > + break; > + > + return NOTIFY_DONE; > +} > + > +static struct notifier_block hb_cpufreq_clk_nb = { > + .notifier_call = hb_cpufreq_clk_notify, > +}; > + > +static int __devinit hb_cpufreq_driver_init(void) Isn't there a big series removing __devinit from the kernel tree as CONFIG_HOTPLUG is going away? Shawn > +{ > + struct device_node *np; > + int ret; > + > + np = of_find_node_by_path("/cpus/cpu@0"); > + 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; > +} > +late_initcall(hb_cpufreq_driver_init); > + > +MODULE_AUTHOR("Mark Langsdorf <mark.langsdorf@calxeda.com>"); > +MODULE_DESCRIPTION("Calxeda Highbank cpufreq driver"); > +MODULE_LICENSE("GPL"); > -- > 1.7.11.7 > -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/arm/boot/dts/highbank.dts b/arch/arm/boot/dts/highbank.dts index 0c6fc34..7c4c27d 100644 --- a/arch/arm/boot/dts/highbank.dts +++ b/arch/arm/boot/dts/highbank.dts @@ -36,6 +36,16 @@ 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@1 { diff --git a/arch/arm/mach-highbank/Kconfig b/arch/arm/mach-highbank/Kconfig index 2896881..b7862da 100644 --- a/arch/arm/mach-highbank/Kconfig +++ b/arch/arm/mach-highbank/Kconfig @@ -1,5 +1,7 @@ config ARCH_HIGHBANK bool "Calxeda ECX-1000 (Highbank)" 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 5961e64..7aaac9f 100644 --- a/drivers/cpufreq/Kconfig.arm +++ b/drivers/cpufreq/Kconfig.arm @@ -76,3 +76,19 @@ config ARM_EXYNOS5250_CPUFREQ help This adds the CPUFreq driver for Samsung EXYNOS5250 SoC. + +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 1bc90e1..9e8f12a 100644 --- a/drivers/cpufreq/Makefile +++ b/drivers/cpufreq/Makefile @@ -50,6 +50,7 @@ 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_HIGHBANK_CPUFREQ) += highbank-cpufreq.o ################################################################################## # PowerPC platform drivers diff --git a/drivers/cpufreq/highbank-cpufreq.c b/drivers/cpufreq/highbank-cpufreq.c new file mode 100644 index 0000000..25ef437 --- /dev/null +++ b/drivers/cpufreq/highbank-cpufreq.c @@ -0,0 +1,106 @@ +/* + * Copyright (C) 2012 Calxeda, Inc. + * + * derived from cpufreq-cpu0 by Freescale Semiconductor + * + * 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) 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/opp.h> +#include <linux/slab.h> +#include <linux/mailbox.h> + +#define HB_CPUFREQ_CHANGE_NOTE 0x80000001 + +static struct device *cpu_dev; +static struct clk *cpu_clk; + +static int hb_voltage_change(unsigned int freq) +{ + int i; + u32 msg[7]; + + msg[0] = HB_CPUFREQ_CHANGE_NOTE; + msg[1] = freq / 1000000; + for (i = 2; i < 7; 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++ > 15) + return NOTIFY_STOP; + } 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++ > 15) + break; + + return NOTIFY_DONE; +} + +static struct notifier_block hb_cpufreq_clk_nb = { + .notifier_call = hb_cpufreq_clk_notify, +}; + +static int __devinit hb_cpufreq_driver_init(void) +{ + struct device_node *np; + int ret; + + np = of_find_node_by_path("/cpus/cpu@0"); + 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; +} +late_initcall(hb_cpufreq_driver_init); + +MODULE_AUTHOR("Mark Langsdorf <mark.langsdorf@calxeda.com>"); +MODULE_DESCRIPTION("Calxeda Highbank cpufreq driver"); +MODULE_LICENSE("GPL");
Highbank processors depend on the external ECME to perform voltage management based on a requested frequency. Communication between the A9 cores and the ECME happens over the pl320 IPC channel. Signed-off-by: Mark Langsdorf <mark.langsdorf@calxeda.com> Cc: shawn.guo@linaro.org Cc: mturquette@ti.com --- Changes from v6 Removed devicetree bindings documentation. Restructured driver to use clk notifications. Core driver logic is now cpufreq-clk0. Changes from v5 Changed ipc_transmit() to pl320_ipc_transmit(). Changes from v4 Removed erroneous changes to arch/arm/Kconfig. Removed unnecessary changes to drivers/cpufreq/Kconfig.arm Alphabetized additions to arch/arm/mach-highbank/Kconfig Changed ipc call and header to match new ipc location in drivers/mailbox. Changes from v3 None. Changes from v2 Changed transition latency binding in code to match documentation. Changes from v1 Added highbank specific Kconfig changes. arch/arm/boot/dts/highbank.dts | 10 ++++ arch/arm/mach-highbank/Kconfig | 2 + drivers/cpufreq/Kconfig.arm | 16 ++++++ drivers/cpufreq/Makefile | 1 + drivers/cpufreq/highbank-cpufreq.c | 106 +++++++++++++++++++++++++++++++++++++ 5 files changed, 135 insertions(+) create mode 100644 drivers/cpufreq/highbank-cpufreq.c