cpufreq: frequency scaling spec in DT node
From: Mason <hidden>
Date: 2017-07-11 13:36:50
Also in:
linux-pm
Subsystem:
cpu frequency scaling framework, the rest · Maintainers:
"Rafael J. Wysocki", Viresh Kumar, Linus Torvalds
On 11/07/2017 11:27, Mason wrote:
I'll experiment with the other solution of creating the OPP table at init.
For the sake of discussion, based on your suggestion to use dev_pm_opp_add(), I have tested the patch below. There is one remaining error: [ 2.071139] of: dev_pm_opp_of_cpumask_add_table: couldn't find opp table for cpu:0, -19 Reached through: [ 1.878461] [<c0359a0c>] (dev_pm_opp_of_add_table) from [<c0359ff0>] (dev_pm_opp_of_cpumask_add_table+0x40/0xc8) [ 1.888695] [<c0359ff0>] (dev_pm_opp_of_cpumask_add_table) from [<c03d66d8>] (cpufreq_init+0x23c/0x2dc) [ 1.898139] [<c03d66d8>] (cpufreq_init) from [<c03d3d94>] (cpufreq_online+0xb8/0x660) [ 1.906009] [<c03d3d94>] (cpufreq_online) from [<c03d43f8>] (cpufreq_add_dev+0xbc/0xcc) [ 1.914058] [<c03d43f8>] (cpufreq_add_dev) from [<c0350560>] (subsys_interface_register+0x90/0xcc) [ 1.923065] [<c0350560>] (subsys_interface_register) from [<c03d32f4>] (cpufreq_register_driver+0x15c/0x1e0) [ 1.932945] [<c03d32f4>] (cpufreq_register_driver) from [<c03d67f0>] (dt_cpufreq_probe+0x78/0xec) [ 1.941866] [<c03d67f0>] (dt_cpufreq_probe) from [<c035327c>] (platform_drv_probe+0x34/0x6c) The cpufreq-dt driver seems to recover despite the error: /sys/devices/system/cpu/cpu0/cpufreq$ cat scaling_available_frequencies 135000 243000 405000 607500 1215000 Regards. arch/arm/boot/dts/tango4-smp8758.dtsi | 1 - drivers/cpufreq/Makefile | 1 + drivers/cpufreq/cpufreq-dt-platdev.c | 2 -- drivers/cpufreq/tango-cpufreq.c | 45 +++++++++++++++++++++++++++++++++++ 4 files changed, 46 insertions(+), 3 deletions(-)
diff --git a/arch/arm/boot/dts/tango4-smp8758.dtsi b/arch/arm/boot/dts/tango4-smp8758.dtsi
index d2e65c46bcc7..eca33d568690 100644
--- a/arch/arm/boot/dts/tango4-smp8758.dtsi
+++ b/arch/arm/boot/dts/tango4-smp8758.dtsi@@ -13,7 +13,6 @@ reg = <0>; clocks = <&clkgen CPU_CLK>; clock-latency = <1>; - operating-points = <1215000 0 607500 0 405000 0 243000 0 135000 0>; }; cpu1: cpu at 1 {
diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile
index 0a9b6a093646..5ae156dc0d35 100644
--- a/drivers/cpufreq/Makefile
+++ b/drivers/cpufreq/Makefile@@ -75,6 +75,7 @@ obj-$(CONFIG_ARM_SA1110_CPUFREQ) += sa1110-cpufreq.o obj-$(CONFIG_ARM_SCPI_CPUFREQ) += scpi-cpufreq.o obj-$(CONFIG_ARM_SPEAR_CPUFREQ) += spear-cpufreq.o obj-$(CONFIG_ARM_STI_CPUFREQ) += sti-cpufreq.o +obj-$(CONFIG_ARCH_TANGO) += tango-cpufreq.o obj-$(CONFIG_ARM_TEGRA20_CPUFREQ) += tegra20-cpufreq.o obj-$(CONFIG_ARM_TEGRA124_CPUFREQ) += tegra124-cpufreq.o obj-$(CONFIG_ARM_VEXPRESS_SPC_CPUFREQ) += vexpress-spc-cpufreq.o
diff --git a/drivers/cpufreq/cpufreq-dt-platdev.c b/drivers/cpufreq/cpufreq-dt-platdev.c
index 71267626456b..1490e4ce3fbc 100644
--- a/drivers/cpufreq/cpufreq-dt-platdev.c
+++ b/drivers/cpufreq/cpufreq-dt-platdev.c@@ -70,8 +70,6 @@ { .compatible = "rockchip,rk3368", }, { .compatible = "rockchip,rk3399", }, - { .compatible = "sigma,tango4" }, - { .compatible = "ti,am33xx", }, { .compatible = "ti,dra7", }, { .compatible = "ti,omap2", },
diff --git a/drivers/cpufreq/tango-cpufreq.c b/drivers/cpufreq/tango-cpufreq.c
new file mode 100644
index 000000000000..270c8261ebfa
--- /dev/null
+++ b/drivers/cpufreq/tango-cpufreq.c@@ -0,0 +1,45 @@ +#include <linux/of.h> +#include <linux/cpu.h> +#include <linux/clk.h> +#include <linux/pm_opp.h> +#include <linux/platform_device.h> + +static const struct of_device_id machines[] __initconst = { + { .compatible = "sigma,tango4" }, + { .compatible = "sigma,tango5" }, + { /* sentinel */ } +}; + +static void __init build_opp_table(struct device *cpu_dev, struct clk *cpu_clk) +{ + unsigned long max_freq = clk_get_rate(cpu_clk); + + dev_pm_opp_add(cpu_dev, max_freq / 1, 0); + dev_pm_opp_add(cpu_dev, max_freq / 2, 0); + dev_pm_opp_add(cpu_dev, max_freq / 3, 0); + dev_pm_opp_add(cpu_dev, max_freq / 5, 0); + dev_pm_opp_add(cpu_dev, max_freq / 9, 0); +} + +static int __init cpufreq_dt_platdev_init(void) +{ + struct device *cpu_dev = get_cpu_device(0); + const struct of_device_id *match; + struct clk *cpu_clk; + void *res; + + match = of_match_node(machines, of_root); + if (!match) + return -ENODEV; + + cpu_clk = clk_get(cpu_dev, NULL); + if (IS_ERR(cpu_clk)) + return -ENODEV; + + build_opp_table(cpu_dev, cpu_clk); + + res = platform_device_register_data(NULL, "cpufreq-dt", -1, NULL, 0); + + return PTR_ERR_OR_ZERO(res); +} +device_initcall(cpufreq_dt_platdev_init);