msm: dcvs: gpu minimum frequency levels

System performance is enhanced if the gpu frequency is given a
minimum corresponding to various frequency levels of CPU 0.

Change-Id: Iba168d708524fc8ef164428bb5f4e0631a499342
Signed-off-by: Steve Muckle <smuckle@codeaurora.org>
(cherry picked from commit 682c7a01c1d86518cdc7bec25cb413498811137b)
diff --git a/arch/arm/mach-msm/devices-8064.c b/arch/arm/mach-msm/devices-8064.c
index 44620a0..af26ec5 100644
--- a/arch/arm/mach-msm/devices-8064.c
+++ b/arch/arm/mach-msm/devices-8064.c
@@ -2626,7 +2626,7 @@
 static struct msm_dcvs_sync_rule apq8064_dcvs_sync_rules[] = {
 	{1026000,	400000},
 	{384000,	200000},
-	{-1,		128000},
+	{0,		128000},
 };
 
 static struct msm_dcvs_platform_data apq8064_dcvs_data = {
diff --git a/arch/arm/mach-msm/include/mach/msm_dcvs.h b/arch/arm/mach-msm/include/mach/msm_dcvs.h
index 1ca5a32..c29b57a 100644
--- a/arch/arm/mach-msm/include/mach/msm_dcvs.h
+++ b/arch/arm/mach-msm/include/mach/msm_dcvs.h
@@ -122,6 +122,7 @@
 	unsigned int (*get_frequency)(int type_core_num),
 	int (*idle_enable)(int type_core_num,
 				enum msm_core_control_event event),
+	int (*set_floor_frequency)(int type_core_num, unsigned int freq),
 	int sensor);
 
 /**
diff --git a/arch/arm/mach-msm/msm_dcvs.c b/arch/arm/mach-msm/msm_dcvs.c
index 358027c..86f4eaf 100644
--- a/arch/arm/mach-msm/msm_dcvs.c
+++ b/arch/arm/mach-msm/msm_dcvs.c
@@ -124,6 +124,7 @@
 	unsigned int (*get_frequency)(int type_core_num);
 	int (*idle_enable)(int type_core_num,
 			enum msm_core_control_event event);
+	int (*set_floor_frequency)(int type_core_num, unsigned int freq);
 
 	spinlock_t	pending_freq_lock;
 	int pending_freq;
@@ -252,6 +253,35 @@
 	spin_unlock_irqrestore(&core->idle_state_change_lock, flags2);
 }
 
+static void apply_gpu_floor(int cpu_freq)
+{
+	int i;
+	int gpu_floor_freq = 0;
+	struct dcvs_core *gpu;
+
+	if (!dcvs_pdata)
+		return;
+
+	for (i = 0; i < dcvs_pdata->num_sync_rules; i++)
+		if (cpu_freq > dcvs_pdata->sync_rules[i].cpu_khz) {
+			gpu_floor_freq =
+				dcvs_pdata->sync_rules[i].gpu_floor_khz;
+			break;
+		}
+
+	if (!gpu_floor_freq)
+		return;
+
+	for (i = GPU_OFFSET; i < CORES_MAX; i++) {
+		gpu = &core_list[i];
+		if (gpu->dcvs_core_id == -1)
+			continue;
+		if (gpu->set_floor_frequency)
+			gpu->set_floor_frequency(gpu->type_core_num,
+						 gpu_floor_freq);
+	}
+}
+
 static int __msm_dcvs_change_freq(struct dcvs_core *core)
 {
 	int ret = 0;
@@ -283,6 +313,10 @@
 
 	spin_unlock_irqrestore(&core->pending_freq_lock, flags);
 
+	if (core->type == MSM_DCVS_CORE_TYPE_CPU &&
+	    core->type_core_num == 0)
+		apply_gpu_floor(requested_freq);
+
 	/**
 	 * Call the frequency sink driver to change the frequency
 	 * We will need to get back the actual frequency in KHz and
@@ -871,6 +905,7 @@
 	unsigned int (*get_frequency)(int type_core_num),
 	int (*idle_enable)(int type_core_num,
 					enum msm_core_control_event event),
+	int (*set_floor_frequency)(int type_core_num, unsigned int freq),
 	int sensor)
 {
 	int ret = -EINVAL;
@@ -894,6 +929,7 @@
 	core->set_frequency = set_frequency;
 	core->get_frequency = get_frequency;
 	core->idle_enable = idle_enable;
+	core->set_floor_frequency = set_floor_frequency;
 	core->pending_freq = STOP_FREQ_CHANGE;
 
 	core->info = info;
diff --git a/drivers/cpufreq/cpufreq_gov_msm.c b/drivers/cpufreq/cpufreq_gov_msm.c
index 6ddbf4e..8f086aa 100644
--- a/drivers/cpufreq/cpufreq_gov_msm.c
+++ b/drivers/cpufreq/cpufreq_gov_msm.c
@@ -253,6 +253,7 @@
 						msm_dcvs_freq_set,
 						msm_dcvs_freq_get,
 						msm_dcvs_idle_notifier,
+						NULL,
 						sensor);
 		if (gov->dcvs_core_id < 0) {
 			pr_err("Unable to register core for %d\n", cpu);
diff --git a/drivers/gpu/msm/kgsl_pwrscale_msm.c b/drivers/gpu/msm/kgsl_pwrscale_msm.c
index b302bee..c680d57 100644
--- a/drivers/gpu/msm/kgsl_pwrscale_msm.c
+++ b/drivers/gpu/msm/kgsl_pwrscale_msm.c
@@ -23,6 +23,8 @@
 	struct kgsl_device		*device;
 	int				enabled;
 	unsigned int			cur_freq;
+	unsigned int			req_level;
+	int				floor_level;
 	struct msm_dcvs_core_info	*core_info;
 	int				gpu_busy;
 	int				dcvs_core_id;
@@ -69,7 +71,39 @@
 		return 0;
 
 	mutex_lock(&device->mutex);
-	kgsl_pwrctrl_pwrlevel_change(device, i);
+	priv->req_level = i;
+	if (priv->req_level <= priv->floor_level) {
+		kgsl_pwrctrl_pwrlevel_change(device, priv->req_level);
+		priv->cur_freq = pwr->pwrlevels[pwr->active_pwrlevel].gpu_freq;
+	}
+	mutex_unlock(&device->mutex);
+
+	/* return current frequency in kHz */
+	return priv->cur_freq / 1000;
+}
+
+static int msm_set_min_freq(int core_num, unsigned int freq)
+{
+	int i, delta = 5000000;
+	struct msm_priv *priv = the_msm_priv;
+	struct kgsl_device *device = priv->device;
+	struct kgsl_pwrctrl *pwr = &device->pwrctrl;
+
+	/* msm_dcvs manager uses frequencies in kHz */
+	freq *= 1000;
+	for (i = 0; i < pwr->num_pwrlevels; i++)
+		if (abs(pwr->pwrlevels[i].gpu_freq - freq) < delta)
+			break;
+	if (i == pwr->num_pwrlevels)
+		return 0;
+
+	mutex_lock(&device->mutex);
+	priv->floor_level = i;
+	if (priv->floor_level <= priv->req_level)
+		kgsl_pwrctrl_pwrlevel_change(device, priv->floor_level);
+	else if (priv->floor_level > priv->req_level)
+		kgsl_pwrctrl_pwrlevel_change(device, priv->req_level);
+
 	priv->cur_freq = pwr->pwrlevels[pwr->active_pwrlevel].gpu_freq;
 	mutex_unlock(&device->mutex);
 
@@ -170,6 +204,7 @@
 
 		priv->core_info = pdata->core_info;
 		tbl = priv->core_info->freq_tbl;
+		priv->floor_level = pwr->num_pwrlevels - 1;
 		/* Fill in frequency table from low to high, reversing order. */
 		low_level = pwr->num_pwrlevels - KGSL_PWRLEVEL_LAST_OFFSET;
 		for (i = 0; i <= low_level; i++)
@@ -180,6 +215,7 @@
 				0,
 				priv->core_info,
 				msm_set_freq, msm_get_freq, msm_idle_enable,
+				msm_set_min_freq,
 				priv->core_info->sensors[0]);
 		if (priv->dcvs_core_id < 0) {
 			KGSL_PWR_ERR(device, "msm_dcvs_register_core failed");