drm/radeon: put UVD PLLs in bypass mode

Just power down the PLL when we get a VCLK or DCLK of zero.
Enabling the bypass mode early should also allow us to
switch UVD clocks on the fly.

Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

3 files changed, 41 insertions, 23 deletions

diff --git a/drivers/gpu/drm/radeon/evergreen.c b/drivers/gpu/drm/radeon/evergreen.c
index d425a4fa0109..0af36e7731e2 100644
--- a/drivers/gpu/drm/radeon/evergreen.c
+++ b/drivers/gpu/drm/radeon/evergreen.c
@@ -189,6 +189,20 @@ int evergreen_set_uvd_clocks(struct radeon_device *rdev, u32 vclk, u32 dclk)
         unsigned vco_freq;
         int r;
 
+        /* bypass vclk and dclk with bclk */
+        WREG32_P(CG_UPLL_FUNC_CNTL_2,
+                VCLK_SRC_SEL(1) | DCLK_SRC_SEL(1),
+                ~(VCLK_SRC_SEL_MASK | DCLK_SRC_SEL_MASK));
+
+        /* put PLL in bypass mode */
+        WREG32_P(CG_UPLL_FUNC_CNTL, UPLL_BYPASS_EN_MASK, ~UPLL_BYPASS_EN_MASK);
+
+        if (!vclk || !dclk) {
+                /* keep the Bypass mode, put PLL to sleep */
+                WREG32_P(CG_UPLL_FUNC_CNTL, UPLL_SLEEP_MASK, ~UPLL_SLEEP_MASK);
+                return 0;
+        }
+
         /* loop through vco from low to high */
         for (vco_freq = 125000; vco_freq <= 250000; vco_freq += 100) {
                 unsigned fb_div = vco_freq / rdev->clock.spll.reference_freq * 16384;
@@ -236,14 +250,6 @@ int evergreen_set_uvd_clocks(struct radeon_device *rdev, u32 vclk, u32 dclk)
 
         mdelay(1);
 
-        /* bypass vclk and dclk with bclk */
-        WREG32_P(CG_UPLL_FUNC_CNTL_2,
-                VCLK_SRC_SEL(1) | DCLK_SRC_SEL(1),
-                ~(VCLK_SRC_SEL_MASK | DCLK_SRC_SEL_MASK));
-
-        /* put PLL in bypass mode */
-        WREG32_P(CG_UPLL_FUNC_CNTL, UPLL_BYPASS_EN_MASK, ~UPLL_BYPASS_EN_MASK);
-
         r = evergreen_uvd_send_upll_ctlreq(rdev);
         if (r)
                 return r;
diff --git a/drivers/gpu/drm/radeon/rv770.c b/drivers/gpu/drm/radeon/rv770.c
index 777f537a32c7..59065ba7c342 100644
--- a/drivers/gpu/drm/radeon/rv770.c
+++ b/drivers/gpu/drm/radeon/rv770.c
@@ -100,6 +100,17 @@ int rv770_set_uvd_clocks(struct radeon_device *rdev, u32 vclk, u32 dclk)
         if (rdev->family == CHIP_RV740)
                 return evergreen_set_uvd_clocks(rdev, vclk, dclk);
 
+        /* bypass vclk and dclk with bclk */
+        WREG32_P(CG_UPLL_FUNC_CNTL_2,
+                 VCLK_SRC_SEL(1) | DCLK_SRC_SEL(1),
+                 ~(VCLK_SRC_SEL_MASK | DCLK_SRC_SEL_MASK));
+
+        if (!vclk || !dclk) {
+                /* keep the Bypass mode, put PLL to sleep */
+                WREG32_P(CG_UPLL_FUNC_CNTL, UPLL_SLEEP_MASK, ~UPLL_SLEEP_MASK);
+                return 0;
+        }
+
         /* loop through vco from low to high */
         vco_min = max(max(vco_min, vclk), dclk);
         for (vco_freq = vco_min; vco_freq <= vco_max; vco_freq += 500) {
@@ -139,16 +150,11 @@ int rv770_set_uvd_clocks(struct radeon_device *rdev, u32 vclk, u32 dclk)
                 }
         }
 
-        /* bypass vclk and dclk with bclk */
-        WREG32_P(CG_UPLL_FUNC_CNTL_2,
-                 VCLK_SRC_SEL(1) | DCLK_SRC_SEL(1),
-                 ~(VCLK_SRC_SEL_MASK | DCLK_SRC_SEL_MASK));
-
         /* set UPLL_FB_DIV to 0x50000 */
         WREG32_P(CG_UPLL_FUNC_CNTL_3, UPLL_FB_DIV(0x50000), ~UPLL_FB_DIV_MASK);
 
-        /* deassert UPLL_RESET */
-        WREG32_P(CG_UPLL_FUNC_CNTL, 0, ~UPLL_RESET_MASK);
+        /* deassert UPLL_RESET and UPLL_SLEEP */
+        WREG32_P(CG_UPLL_FUNC_CNTL, 0, ~(UPLL_RESET_MASK | UPLL_SLEEP_MASK));
 
         /* assert BYPASS EN and FB_DIV[0] <- ??? why? */
         WREG32_P(CG_UPLL_FUNC_CNTL, UPLL_BYPASS_EN_MASK, ~UPLL_BYPASS_EN_MASK);
diff --git a/drivers/gpu/drm/radeon/si.c b/drivers/gpu/drm/radeon/si.c
index aa2c555ba877..b7d78f24cc26 100644
--- a/drivers/gpu/drm/radeon/si.c
+++ b/drivers/gpu/drm/radeon/si.c
@@ -4680,6 +4680,20 @@ int si_set_uvd_clocks(struct radeon_device *rdev, u32 vclk, u32 dclk)
         unsigned vco_freq;
         int r;
 
+        /* bypass vclk and dclk with bclk */
+        WREG32_P(CG_UPLL_FUNC_CNTL_2,
+                VCLK_SRC_SEL(1) | DCLK_SRC_SEL(1),
+                ~(VCLK_SRC_SEL_MASK | DCLK_SRC_SEL_MASK));
+
+        /* put PLL in bypass mode */
+        WREG32_P(CG_UPLL_FUNC_CNTL, UPLL_BYPASS_EN_MASK, ~UPLL_BYPASS_EN_MASK);
+
+        if (!vclk || !dclk) {
+                /* keep the Bypass mode, put PLL to sleep */
+                WREG32_P(CG_UPLL_FUNC_CNTL, UPLL_SLEEP_MASK, ~UPLL_SLEEP_MASK);
+                return 0;
+        }
+
         /* loop through vco from low to high */
         for (vco_freq = 125000; vco_freq <= 250000; vco_freq += 100) {
                 unsigned fb_div = vco_freq / rdev->clock.spll.reference_freq * 16384;
@@ -4730,14 +4744,6 @@ int si_set_uvd_clocks(struct radeon_device *rdev, u32 vclk, u32 dclk)
 
         mdelay(1);
 
-        /* bypass vclk and dclk with bclk */
-        WREG32_P(CG_UPLL_FUNC_CNTL_2,
-                VCLK_SRC_SEL(1) | DCLK_SRC_SEL(1),
-                ~(VCLK_SRC_SEL_MASK | DCLK_SRC_SEL_MASK));
-
-        /* put PLL in bypass mode */
-        WREG32_P(CG_UPLL_FUNC_CNTL, UPLL_BYPASS_EN_MASK, ~UPLL_BYPASS_EN_MASK);
-
         r = si_uvd_send_upll_ctlreq(rdev);
         if (r)
                 return r;