[PATCH 2/3]: Support cpu frequency scaling and power management for iMX6SL

[PATCH 2/3]: Support cpu frequency scaling and power management for iMX6SL

[John Tobias]

iMX6SL re-using iMX6Q driver in order to enable the cpu frequency
scaling and power management

From: John Tobias <john.tobias.ph@gmail.com>


diff --git a/arch/arm/mach-imx/mach-imx6sl.c b/arch/arm/mach-imx/mach-imx6sl.c
index 2f952e3..e66eccf 100644
--- a/arch/arm/mach-imx/mach-imx6sl.c
+++ b/arch/arm/mach-imx/mach-imx6sl.c
@@ -9,7 +9,10 @@

 #include <linux/irqchip.h>
 #include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
 #include <linux/of_platform.h>
+#include <linux/pm_opp.h>
 #include <linux/mfd/syscon.h>
 #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
 #include <linux/regmap.h>
@@ -17,6 +20,7 @@
 #include <asm/mach/map.h>

 #include "common.h"
+#include "cpuidle.h"

 static void __init imx6sl_fec_init(void)
 {
@@ -34,6 +38,47 @@ static void __init imx6sl_fec_init(void)
        }
 }

+
+static void __init imx6sl_opp_init(void)
+{
+       struct device_node *np;
+       struct device *cpu_dev = get_cpu_device(0);
+
+       if (!cpu_dev) {
+               pr_warn("failed to get cpu0 device\n");
+               return;
+       }
+       np = of_node_get(cpu_dev->of_node);
+       if (!np) {
+               pr_warn("failed to find cpu0 node\n");
+               return;
+       }
+
+       if (of_init_opp_table(cpu_dev)) {
+               pr_warn("failed to init OPP table\n");
+               goto put_node;
+       }
+
+put_node:
+       of_node_put(np);
+}
+
+static struct platform_device imx6q_cpufreq_pdev = {
+       .name = "imx6q-cpufreq",
+};
+
+
+static void __init imx6sl_init_late(void)
+{
+       /* re-use imx6q */
+       imx6q_cpuidle_init();
+
+       if (IS_ENABLED(CONFIG_ARM_IMX6SQ_CPUFREQ)) {
+               imx6sl_opp_init();
+               platform_device_register(&imx6q_cpufreq_pdev);
+       }
+}
+
 static void __init imx6sl_init_machine(void)
 {
        struct device *parent;
@@ -70,6 +115,7 @@ DT_MACHINE_START(IMX6SL, "Freescale i.MX6 SoloLite
(Device Tree)")
        .map_io         = debug_ll_io_init,
        .init_irq       = imx6sl_init_irq,
        .init_machine   = imx6sl_init_machine,
+       .init_late      = imx6sl_init_late,
        .dt_compat      = imx6sl_dt_compat,
        .restart        = mxc_restart,
 MACHINE_END

[PATCH 2/3]: Support cpu frequency scaling and power management for iMX6SL

[Shawn Guo]

On Mon, Dec 16, 2013 at 05:40:18PM -0800, John Tobias wrote:
> iMX6SL re-using iMX6Q driver in order to enable the cpu frequency
> scaling and power management
> 
> From: John Tobias <john.tobias.ph@gmail.com>
> 
> 
> diff --git a/arch/arm/mach-imx/mach-imx6sl.c b/arch/arm/mach-imx/mach-imx6sl.c
> index 2f952e3..e66eccf 100644
> --- a/arch/arm/mach-imx/mach-imx6sl.c
> +++ b/arch/arm/mach-imx/mach-imx6sl.c
> @@ -9,7 +9,10 @@
> 
>  #include <linux/irqchip.h>
>  #include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/of_irq.h>
>  #include <linux/of_platform.h>
> +#include <linux/pm_opp.h>
>  #include <linux/mfd/syscon.h>
>  #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
>  #include <linux/regmap.h>
> @@ -17,6 +20,7 @@
>  #include <asm/mach/map.h>
> 
>  #include "common.h"
> +#include "cpuidle.h"
> 
>  static void __init imx6sl_fec_init(void)
>  {
> @@ -34,6 +38,47 @@ static void __init imx6sl_fec_init(void)
>         }
>  }
> 
> +

One blank line is enough.

> +static void __init imx6sl_opp_init(void)
> +{
> +       struct device_node *np;
> +       struct device *cpu_dev = get_cpu_device(0);
> +
> +       if (!cpu_dev) {
> +               pr_warn("failed to get cpu0 device\n");
> +               return;
> +       }
> +       np = of_node_get(cpu_dev->of_node);
> +       if (!np) {
> +               pr_warn("failed to find cpu0 node\n");
> +               return;
> +       }
> +
> +       if (of_init_opp_table(cpu_dev)) {
> +               pr_warn("failed to init OPP table\n");
> +               goto put_node;
> +       }
> +
> +put_node:
> +       of_node_put(np);
> +}

We have this for imx6q, because we need to check 1.2GHz case.  But
I hope we can improve imx6q-cpufreq driver to invoke of_init_opp_table()
from there, if platform does not supply an opp table, so that we can
save these code in platform for most of cases.

> +
> +static struct platform_device imx6q_cpufreq_pdev = {
> +       .name = "imx6q-cpufreq",
> +};
> +
> +
> +static void __init imx6sl_init_late(void)
> +{
> +       /* re-use imx6q */
> +       imx6q_cpuidle_init();

It's not about cpufreq.  The change does not belong to this patch.

> +
> +       if (IS_ENABLED(CONFIG_ARM_IMX6SQ_CPUFREQ)) {

IMX6SQ?

Shawn

> +               imx6sl_opp_init();
> +               platform_device_register(&imx6q_cpufreq_pdev);
> +       }
> +}
> +
>  static void __init imx6sl_init_machine(void)
>  {
>         struct device *parent;
> @@ -70,6 +115,7 @@ DT_MACHINE_START(IMX6SL, "Freescale i.MX6 SoloLite
> (Device Tree)")
>         .map_io         = debug_ll_io_init,
>         .init_irq       = imx6sl_init_irq,
>         .init_machine   = imx6sl_init_machine,
> +       .init_late      = imx6sl_init_late,
>         .dt_compat      = imx6sl_dt_compat,
>         .restart        = mxc_restart,
>  MACHINE_END