drm/radeon/dpm: implement force performance levels for rs780 (v2)

Allows you to limit the selected power levels via sysfs.

Force the feedback divider to select a power level.

v2: fix checking in rs780_force_fbdiv,
    drop a duplicate divider structure in rs780_dpm_force_performance_level,
    Force the voltage level too.

Signed-off-by: Anthoine Bourgeois <anthoine.bourgeois@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

3 files changed, 77 insertions, 15 deletions

diff --git a/drivers/gpu/drm/radeon/radeon_asic.c b/drivers/gpu/drm/radeon/radeon_asic.c
index 630853b96841..40a9b4bc3291 100644
--- a/drivers/gpu/drm/radeon/radeon_asic.c
+++ b/drivers/gpu/drm/radeon/radeon_asic.c
@@ -1141,6 +1141,7 @@ static struct radeon_asic rs780_asic = {
                 .get_mclk = &rs780_dpm_get_mclk,
                 .print_power_state = &rs780_dpm_print_power_state,
                 .debugfs_print_current_performance_level = &rs780_dpm_debugfs_print_current_performance_level,
+                .force_performance_level = &rs780_dpm_force_performance_level,
         },
         .pflip = {
                 .pre_page_flip = &rs600_pre_page_flip,
diff --git a/drivers/gpu/drm/radeon/radeon_asic.h b/drivers/gpu/drm/radeon/radeon_asic.h
index 818bbe6b884b..98a59f5d6edc 100644
--- a/drivers/gpu/drm/radeon/radeon_asic.h
+++ b/drivers/gpu/drm/radeon/radeon_asic.h
@@ -428,6 +428,8 @@ void rs780_dpm_print_power_state(struct radeon_device *rdev,
                                  struct radeon_ps *ps);
 void rs780_dpm_debugfs_print_current_performance_level(struct radeon_device *rdev,
                                                        struct seq_file *m);
+int rs780_dpm_force_performance_level(struct radeon_device *rdev,
+                                      enum radeon_dpm_forced_level level);
 
 /*
  * rv770,rv730,rv710,rv740
diff --git a/drivers/gpu/drm/radeon/rs780_dpm.c b/drivers/gpu/drm/radeon/rs780_dpm.c
index d1a1ce73bd45..625d6ea1f0d1 100644
--- a/drivers/gpu/drm/radeon/rs780_dpm.c
+++ b/drivers/gpu/drm/radeon/rs780_dpm.c
@@ -376,9 +376,8 @@ static void rs780_disable_vbios_powersaving(struct radeon_device *rdev)
         WREG32_P(CG_INTGFX_MISC, 0, ~0xFFF00000);
 }
 
-static void rs780_force_voltage_to_high(struct radeon_device *rdev)
+static void rs780_force_voltage(struct radeon_device *rdev, u16 voltage)
 {
-        struct igp_power_info *pi = rs780_get_pi(rdev);
         struct igp_ps *current_state = rs780_get_ps(rdev->pm.dpm.current_ps);
 
         if ((current_state->max_voltage == RS780_VDDC_LEVEL_HIGH) &&
@@ -390,7 +389,7 @@ static void rs780_force_voltage_to_high(struct radeon_device *rdev)
         udelay(1);
 
         WREG32_P(FVTHROT_PWM_CTRL_REG0,
-                 STARTING_PWM_HIGHTIME(pi->max_voltage),
+                 STARTING_PWM_HIGHTIME(voltage),
                  ~STARTING_PWM_HIGHTIME_MASK);
 
         WREG32_P(FVTHROT_PWM_CTRL_REG0,
@@ -404,6 +403,26 @@ static void rs780_force_voltage_to_high(struct radeon_device *rdev)
         WREG32_P(GFX_MACRO_BYPASS_CNTL, 0, ~SPLL_BYPASS_CNTL);
 }
 
+static void rs780_force_fbdiv(struct radeon_device *rdev, u32 fb_div)
+{
+        struct igp_ps *current_state = rs780_get_ps(rdev->pm.dpm.current_ps);
+
+        if (current_state->sclk_low == current_state->sclk_high)
+                return;
+
+        WREG32_P(GFX_MACRO_BYPASS_CNTL, SPLL_BYPASS_CNTL, ~SPLL_BYPASS_CNTL);
+
+        WREG32_P(FVTHROT_FBDIV_REG2, FORCED_FEEDBACK_DIV(fb_div),
+                 ~FORCED_FEEDBACK_DIV_MASK);
+        WREG32_P(FVTHROT_FBDIV_REG1, STARTING_FEEDBACK_DIV(fb_div),
+                 ~STARTING_FEEDBACK_DIV_MASK);
+        WREG32_P(FVTHROT_FBDIV_REG1, FORCE_FEEDBACK_DIV, ~FORCE_FEEDBACK_DIV);
+
+        udelay(100);
+
+        WREG32_P(GFX_MACRO_BYPASS_CNTL, 0, ~SPLL_BYPASS_CNTL);
+}
+
 static int rs780_set_engine_clock_scaling(struct radeon_device *rdev,
                                           struct radeon_ps *new_ps,
                                           struct radeon_ps *old_ps)
@@ -432,17 +451,7 @@ static int rs780_set_engine_clock_scaling(struct radeon_device *rdev,
         if (ret)
                 return ret;
 
-        WREG32_P(GFX_MACRO_BYPASS_CNTL, SPLL_BYPASS_CNTL, ~SPLL_BYPASS_CNTL);
-
-        WREG32_P(FVTHROT_FBDIV_REG2, FORCED_FEEDBACK_DIV(max_dividers.fb_div),
-                 ~FORCED_FEEDBACK_DIV_MASK);
-        WREG32_P(FVTHROT_FBDIV_REG1, STARTING_FEEDBACK_DIV(max_dividers.fb_div),
-                 ~STARTING_FEEDBACK_DIV_MASK);
-        WREG32_P(FVTHROT_FBDIV_REG1, FORCE_FEEDBACK_DIV, ~FORCE_FEEDBACK_DIV);
-
-        udelay(100);
-
-        WREG32_P(GFX_MACRO_BYPASS_CNTL, 0, ~SPLL_BYPASS_CNTL);
+        rs780_force_fbdiv(rdev, max_dividers.fb_div);
 
         if (max_dividers.fb_div > min_dividers.fb_div) {
                 WREG32_P(FVTHROT_FBDIV_REG0,
@@ -649,7 +658,7 @@ int rs780_dpm_set_power_state(struct radeon_device *rdev)
         rs780_set_uvd_clock_before_set_eng_clock(rdev, new_ps, old_ps);
 
         if (pi->voltage_control) {
-                rs780_force_voltage_to_high(rdev);
+                rs780_force_voltage(rdev, pi->max_voltage);
                 mdelay(5);
         }
 
@@ -986,3 +995,53 @@ void rs780_dpm_debugfs_print_current_performance_level(struct radeon_device *rde
                 seq_printf(m, "power level 1    sclk: %u vddc_index: %d\n",
                            ps->sclk_high, ps->max_voltage);
 }
+
+int rs780_dpm_force_performance_level(struct radeon_device *rdev,
+                                      enum radeon_dpm_forced_level level)
+{
+        struct igp_power_info *pi = rs780_get_pi(rdev);
+        struct radeon_ps *rps = rdev->pm.dpm.current_ps;
+        struct igp_ps *ps = rs780_get_ps(rps);
+        struct atom_clock_dividers dividers;
+        int ret;
+
+        rs780_clk_scaling_enable(rdev, false);
+        rs780_voltage_scaling_enable(rdev, false);
+
+        if (level == RADEON_DPM_FORCED_LEVEL_HIGH) {
+                if (pi->voltage_control)
+                        rs780_force_voltage(rdev, pi->max_voltage);
+
+                ret = radeon_atom_get_clock_dividers(rdev, COMPUTE_ENGINE_PLL_PARAM,
+                                                     ps->sclk_high, false, &dividers);
+                if (ret)
+                        return ret;
+
+                rs780_force_fbdiv(rdev, dividers.fb_div);
+        } else if (level == RADEON_DPM_FORCED_LEVEL_LOW) {
+                ret = radeon_atom_get_clock_dividers(rdev, COMPUTE_ENGINE_PLL_PARAM,
+                                                     ps->sclk_low, false, &dividers);
+                if (ret)
+                        return ret;
+
+                rs780_force_fbdiv(rdev, dividers.fb_div);
+
+                if (pi->voltage_control)
+                        rs780_force_voltage(rdev, pi->min_voltage);
+        } else {
+                if (pi->voltage_control)
+                        rs780_force_voltage(rdev, pi->max_voltage);
+
+                WREG32_P(FVTHROT_FBDIV_REG1, 0, ~FORCE_FEEDBACK_DIV);
+                rs780_clk_scaling_enable(rdev, true);
+
+                if (pi->voltage_control) {
+                        rs780_voltage_scaling_enable(rdev, true);
+                        rs780_enable_voltage_scaling(rdev, rps);
+                }
+        }
+
+        rdev->pm.dpm.forced_level = level;
+
+        return 0;
+}