arm: tegra: dvfs: Add cpu clock switch cdev

- Add cpu clock switch cooling device to switch
  between PLL and DFLL  dynamically based
  on temperature.

Bug 200002255

Change-Id: I098d41eb64ec53a284db310131c4f604c808645c
Signed-off-by: sreenivasulu velpula <svelpula@nvidia.com>
Reviewed-on: http://git-master/r/439762
Reviewed-by: Sandeep Trasi <strasi@nvidia.com>
Tested-by: Sandeep Trasi <strasi@nvidia.com>

diff --git a/arch/arm/mach-tegra/dvfs.c b/arch/arm/mach-tegra/dvfs.c
index 5842e2a67fd06d4d9c72ba2669fc63d918cf576e..ab4c686a52bf7f6f60be40c31cdac9dbf569675d 100644 (file)
--- a/arch/arm/mach-tegra/dvfs.c
+++ b/arch/arm/mach-tegra/dvfs.c
@@ -131,6 +131,13 @@ static void dvfs_validate_cdevs(struct dvfs_rail *rail)
                WARN(1, "%s: thermal dvfs is not supported\n", rail->reg_id);
        }
 
+       /* Thermal clock switch is only supported for CPU */
+       if (rail->clk_switch_cdev && (rail != tegra_cpu_rail)) {
+               rail->clk_switch_cdev = NULL;
+                WARN(1, "%s: thermal clock switch is not supported\n",
+                               rail->reg_id);
+       }
+
        if (!rail->simon_vmin_offsets != !rail->simon_vmin_offs_num) {
                rail->simon_vmin_offs_num = 0;
                rail->simon_vmin_offsets = NULL;
@@ -1726,6 +1733,13 @@ struct tegra_cooling_device *tegra_dvfs_get_gpu_vts_cdev(void)
        return NULL;
 }
 
+struct tegra_cooling_device *tegra_dvfs_get_cpu_clk_switch_cdev(void)
+{
+       if (tegra_cpu_rail)
+               return tegra_cpu_rail->clk_switch_cdev;
+       return NULL;
+}
+
 static void make_safe_thermal_dvfs(struct dvfs_rail *rail)
 {
        struct dvfs *d;
@@ -1850,6 +1864,72 @@ void tegra_dvfs_rail_register_vmax_cdev(struct dvfs_rail *rail)
        }
 }
 
+/* Cooling device to switch the cpu clock source between PLLX and DFLL */
+static int tegra_dvfs_rail_get_clk_switch_cdev_max_state(
+       struct thermal_cooling_device *cdev, unsigned long *max_state)
+{
+       struct dvfs_rail *rail = (struct dvfs_rail *)cdev->devdata;
+       *max_state = rail->clk_switch_cdev->trip_temperatures_num;
+       return 0;
+}
+
+static int tegra_dvfs_rail_get_clk_switch_cdev_cur_state(
+       struct thermal_cooling_device *cdev, unsigned long *cur_state)
+{
+       struct dvfs_rail *rail = (struct dvfs_rail *)cdev->devdata;
+       *cur_state = rail->therm_scale_idx;
+       return 0;
+}
+
+static int tegra_dvfs_rail_set_clk_switch_cdev_state(
+       struct thermal_cooling_device *cdev, unsigned long cur_state)
+{
+       int ret = 0;
+       enum dfll_range use_dfll;
+       struct dvfs_rail *rail = (struct dvfs_rail *)cdev->devdata;
+
+       if (CONFIG_TEGRA_USE_DFLL_RANGE == TEGRA_USE_DFLL_CDEV_CNTRL) {
+               if (rail->therm_scale_idx != cur_state) {
+                       rail->therm_scale_idx = cur_state;
+                       if (rail->therm_scale_idx == 0)
+                               use_dfll = DFLL_RANGE_NONE;
+                       else
+                               use_dfll = DFLL_RANGE_ALL_RATES;
+
+                       ret = tegra_clk_dfll_range_control(use_dfll);
+               }
+       } else {
+               pr_warn("\n%s: Not Allowed:", __func__);
+               pr_warn("DFLL is not under thermal cooling device control\n");
+               return -EACCES;
+       }
+       return ret;
+}
+
+static struct thermal_cooling_device_ops tegra_dvfs_clk_cooling_ops = {
+       .get_max_state = tegra_dvfs_rail_get_clk_switch_cdev_max_state,
+       .get_cur_state = tegra_dvfs_rail_get_clk_switch_cdev_cur_state,
+       .set_cur_state = tegra_dvfs_rail_set_clk_switch_cdev_state,
+};
+
+static void tegra_dvfs_rail_register_clk_switch_cdev(struct dvfs_rail *rail)
+{
+       struct thermal_cooling_device *dev;
+
+       if (!rail->clk_switch_cdev)
+               return;
+
+       dev = thermal_cooling_device_register(rail->clk_switch_cdev->cdev_type,
+               (void *)rail, &tegra_dvfs_clk_cooling_ops);
+       /* report error & set max limits across thermal ranges as safe dvfs */
+       if (IS_ERR_OR_NULL(dev) || list_empty(&dev->thermal_instances)) {
+               pr_err("tegra cooling device %s failed to register\n",
+                      rail->clk_switch_cdev->cdev_type);
+               make_safe_thermal_dvfs(rail);
+       }
+}
+
+
 /* Cooling device to scale voltage with temperature in pll mode */
 static int tegra_dvfs_rail_get_vts_cdev_max_state(
        struct thermal_cooling_device *cdev, unsigned long *max_state)
@@ -2002,6 +2082,33 @@ void __init tegra_dvfs_rail_init_vmax_thermal_profile(
        }
 }
 
+int  __init tegra_dvfs_rail_init_clk_switch_thermal_profile(
+       int *clk_switch_trips, struct dvfs_rail *rail)
+{
+       int i;
+
+       if (!rail->clk_switch_cdev) {
+               WARN(1, "%s: missing thermal dvfs cooling device\n",
+                       rail->reg_id);
+               return -ENOENT;
+       }
+
+       for (i = 0; i < MAX_THERMAL_LIMITS - 1; i++) {
+               if (clk_switch_trips[i] >= clk_switch_trips[i+1])
+                       break;
+       }
+
+       /*Only one trip point is allowed for this cdev*/
+       if (i != 0) {
+               WARN(1, "%s: Only one trip point allowed\n", __func__);
+               return -EINVAL;
+       }
+
+       rail->clk_switch_cdev->trip_temperatures_num = i + 1;
+       rail->clk_switch_cdev->trip_temperatures = clk_switch_trips;
+       return 0;
+}
+
 void __init tegra_dvfs_rail_init_vmin_thermal_profile(
        int *therm_trips_table, int *therm_floors_table,
        struct dvfs_rail *rail, struct dvfs_dfll_data *d)
@@ -2201,6 +2308,8 @@ int __init tegra_dvfs_rail_register_notifiers(void)
        list_for_each_entry(rail, &dvfs_rail_list, node) {
                        tegra_dvfs_rail_register_vmin_cdev(rail);
                        tegra_dvfs_rail_register_vts_cdev(rail);
+                       tegra_dvfs_rail_register_clk_switch_cdev(rail);
+
        }
 
        return 0;

diff --git a/arch/arm/mach-tegra/dvfs.h b/arch/arm/mach-tegra/dvfs.h
index 9c517b4ebcba854980ca54727538f33caa340058..6d888c631ee2684470f3250460535a44dd4b8c51 100644 (file)
--- a/arch/arm/mach-tegra/dvfs.h
+++ b/arch/arm/mach-tegra/dvfs.h
@@ -115,6 +115,10 @@ struct dvfs_rail {
        struct tegra_cooling_device *vmin_cdev;
        struct tegra_cooling_device *vmax_cdev;
        struct tegra_cooling_device *vts_cdev;
+
+       /* Used for CPU clock switch between PLLX and DFLL */
+       struct tegra_cooling_device *clk_switch_cdev;
+
        struct rail_alignment alignment;
        struct rail_stats stats;
        const char *version;
@@ -213,6 +217,7 @@ struct cvb_dvfs {
        int vmin_trips_table[MAX_THERMAL_LIMITS];
        int therm_floors_table[MAX_THERMAL_LIMITS];
        int vts_trips_table[MAX_THERMAL_LIMITS];
+       int clk_switch_trips[MAX_THERMAL_LIMITS];
 };
 
 #define cpu_cvb_dvfs   cvb_dvfs
@@ -293,6 +298,7 @@ struct tegra_cooling_device *tegra_dvfs_get_core_vmax_cdev(void);
 struct tegra_cooling_device *tegra_dvfs_get_core_vmin_cdev(void);
 struct tegra_cooling_device *tegra_dvfs_get_gpu_vmin_cdev(void);
 struct tegra_cooling_device *tegra_dvfs_get_gpu_vts_cdev(void);
+struct tegra_cooling_device *tegra_dvfs_get_cpu_clk_switch_cdev(void);
 #ifdef CONFIG_TEGRA_USE_SIMON
 void tegra_dvfs_rail_init_simon_vmin_offsets(
        int *offsets, int offs_num, struct dvfs_rail *rail);
@@ -307,6 +313,8 @@ void tegra_dvfs_rail_init_vmin_thermal_profile(
 void tegra_dvfs_rail_init_vmax_thermal_profile(
        int *therm_trips_table, int *therm_caps_table,
        struct dvfs_rail *rail, struct dvfs_dfll_data *d);
+int __init tegra_dvfs_rail_init_clk_switch_thermal_profile(
+       int *clk_switch_trips, struct dvfs_rail *rail);
 int tegra_dvfs_rail_init_thermal_dvfs_trips(
        int *therm_trips_table, struct dvfs_rail *rail);
 int tegra_dvfs_init_thermal_dvfs_voltages(int *millivolts,