[Intel-gfx] [BXT MIPI PATCH v3 02/14] drm/i915/bxt: Enable BXT DSI PLL
Uma Shankar
uma.shankar at intel.com
Tue Sep 1 07:11:38 PDT 2015
From: Shashank Sharma <shashank.sharma at intel.com>
This patch adds new functions for BXT clock and PLL programming.
They are:
1. configure_dsi_pll for BXT.
This function does the basic math and generates the divider ratio
based on requested pixclock, and program clock registers.
2. enable_dsi_pll function.
This function programs the calculated clock values on the PLL.
3. intel_enable_dsi_pll
Wrapper function to use same code for multiple platforms. It checks the
platform and calls appropriate core pll enable function.
v2: Fixed Jani's review comments. Macros are adjusted as per convention.
v3: Removed a redundant change wrt code comment.
Signed-off-by: Shashank Sharma <shashank.sharma at intel.com>
Signed-off-by: Uma Shankar <uma.shankar at intel.com>
---
drivers/gpu/drm/i915/i915_reg.h | 22 ++++++++
drivers/gpu/drm/i915/intel_dsi.c | 2 +-
drivers/gpu/drm/i915/intel_dsi.h | 2 +-
drivers/gpu/drm/i915/intel_dsi_pll.c | 95 +++++++++++++++++++++++++++++++++-
4 files changed, 118 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 621151b..06bb2e1 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -7362,6 +7362,28 @@ enum skl_disp_power_wells {
#define _MIPI_PORT(port, a, c) _PORT3(port, a, 0, c) /* ports A and C only */
+#define BXT_DSI_PLL_CTL 0x161000
+#define BXT_DSI_PLL_PVD_RATIO_SHIFT 16
+#define BXT_DSI_PLL_PVD_RATIO_MASK (3 << BXT_DSI_PLL_PVD_RATIO_SHIFT)
+#define BXT_DSI_PLL_PVD_RATIO_1 (1 << BXT_DSI_PLL_PVD_RATIO_SHIFT)
+#define BXT_DSIC_16X_BY2 (1 << 10)
+#define BXT_DSIC_16X_BY3 (2 << 10)
+#define BXT_DSIC_16X_BY4 (3 << 10)
+#define BXT_DSIA_16X_BY2 (1 << 8)
+#define BXT_DSIA_16X_BY3 (2 << 8)
+#define BXT_DSIA_16X_BY4 (3 << 8)
+#define BXT_DSI_FREQ_SEL_SHIFT 8
+#define BXT_DSI_FREQ_SEL_MASK (0xF << BXT_DSI_FREQ_SEL_SHIFT)
+
+#define BXT_DSI_PLL_RATIO_MAX 0x7D
+#define BXT_DSI_PLL_RATIO_MIN 0x22
+#define BXT_DSI_PLL_RATIO_MASK 0xFF
+#define BXT_REF_CLOCK_KHZ 19500
+
+#define BXT_DSI_PLL_ENABLE 0x46080
+#define BXT_DSI_PLL_DO_ENABLE (1 << 31)
+#define BXT_DSI_PLL_LOCKED (1 << 30)
+
#define _MIPIA_PORT_CTRL (VLV_DISPLAY_BASE + 0x61190)
#define _MIPIC_PORT_CTRL (VLV_DISPLAY_BASE + 0x61700)
#define MIPI_PORT_CTRL(port) _MIPI_PORT(port, _MIPIA_PORT_CTRL, _MIPIC_PORT_CTRL)
diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
index b59b828..fb259fb 100644
--- a/drivers/gpu/drm/i915/intel_dsi.c
+++ b/drivers/gpu/drm/i915/intel_dsi.c
@@ -903,8 +903,8 @@ static void intel_dsi_pre_pll_enable(struct intel_encoder *encoder)
DRM_DEBUG_KMS("\n");
intel_dsi_prepare(encoder);
+ intel_enable_dsi_pll(encoder);
- vlv_enable_dsi_pll(encoder);
}
static enum drm_connector_status
diff --git a/drivers/gpu/drm/i915/intel_dsi.h b/drivers/gpu/drm/i915/intel_dsi.h
index 2784ac4..20cfcf07 100644
--- a/drivers/gpu/drm/i915/intel_dsi.h
+++ b/drivers/gpu/drm/i915/intel_dsi.h
@@ -121,7 +121,7 @@ static inline struct intel_dsi *enc_to_intel_dsi(struct drm_encoder *encoder)
return container_of(encoder, struct intel_dsi, base.base);
}
-extern void vlv_enable_dsi_pll(struct intel_encoder *encoder);
+extern void intel_enable_dsi_pll(struct intel_encoder *encoder);
extern void vlv_disable_dsi_pll(struct intel_encoder *encoder);
extern u32 vlv_get_dsi_pclk(struct intel_encoder *encoder, int pipe_bpp);
diff --git a/drivers/gpu/drm/i915/intel_dsi_pll.c b/drivers/gpu/drm/i915/intel_dsi_pll.c
index d20cf37..3830a4f 100644
--- a/drivers/gpu/drm/i915/intel_dsi_pll.c
+++ b/drivers/gpu/drm/i915/intel_dsi_pll.c
@@ -237,7 +237,7 @@ static void vlv_configure_dsi_pll(struct intel_encoder *encoder)
vlv_cck_write(dev_priv, CCK_REG_DSI_PLL_CONTROL, dsi_mnp.dsi_pll_ctrl);
}
-void vlv_enable_dsi_pll(struct intel_encoder *encoder)
+static void vlv_enable_dsi_pll(struct intel_encoder *encoder)
{
struct drm_i915_private *dev_priv = encoder->base.dev->dev_private;
u32 tmp;
@@ -368,3 +368,96 @@ u32 vlv_get_dsi_pclk(struct intel_encoder *encoder, int pipe_bpp)
return pclk;
}
+
+static bool bxt_configure_dsi_pll(struct intel_encoder *encoder)
+{
+ struct drm_i915_private *dev_priv = encoder->base.dev->dev_private;
+ struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
+ u8 dsi_ratio;
+ u32 dsi_clk;
+ u32 val;
+
+ dsi_clk = dsi_clk_from_pclk(intel_dsi->pclk, intel_dsi->pixel_format,
+ intel_dsi->lane_count);
+
+ /*
+ * From clock diagram, to get PLL ratio divider, divide double of DSI
+ * link rate (i.e., 2*8x=16x frequency value) by ref clock. Make sure to
+ * round 'up' the result
+ */
+ dsi_ratio = DIV_ROUND_UP(dsi_clk * 2, BXT_REF_CLOCK_KHZ);
+ if (dsi_ratio < BXT_DSI_PLL_RATIO_MIN ||
+ dsi_ratio > BXT_DSI_PLL_RATIO_MAX) {
+ DRM_ERROR("Cant get a suitable ratio from DSI PLL ratios\n");
+ return false;
+ }
+
+ /*
+ * Program DSI ratio and Select MIPIC and MIPIA PLL output as 8x
+ * Spec says both have to be programmed, even if one is not getting
+ * used. Configure MIPI_CLOCK_CTL dividers in modeset
+ */
+ val = I915_READ(BXT_DSI_PLL_CTL);
+ val &= ~BXT_DSI_PLL_PVD_RATIO_MASK;
+ val &= ~BXT_DSI_FREQ_SEL_MASK;
+ val &= ~BXT_DSI_PLL_RATIO_MASK;
+ val |= (dsi_ratio | BXT_DSIA_16X_BY2 | BXT_DSIC_16X_BY2);
+
+ /* As per recommendation from hardware team,
+ * Prog PVD ratio =1 if dsi ratio <= 50
+ */
+ if (dsi_ratio <= 50) {
+ val &= ~BXT_DSI_PLL_PVD_RATIO_MASK;
+ val |= BXT_DSI_PLL_PVD_RATIO_1;
+ }
+
+ I915_WRITE(BXT_DSI_PLL_CTL, val);
+ POSTING_READ(BXT_DSI_PLL_CTL);
+
+ return true;
+}
+
+static void bxt_enable_dsi_pll(struct intel_encoder *encoder)
+{
+ struct drm_i915_private *dev_priv = encoder->base.dev->dev_private;
+ u32 val;
+
+ DRM_DEBUG_KMS("\n");
+
+ val = I915_READ(BXT_DSI_PLL_ENABLE);
+
+ if (val & BXT_DSI_PLL_DO_ENABLE) {
+ WARN(1, "DSI PLL already enabled. Disabling it.\n");
+ val &= ~BXT_DSI_PLL_DO_ENABLE;
+ I915_WRITE(BXT_DSI_PLL_ENABLE, val);
+ }
+
+ /* Configure PLL vales */
+ if (!bxt_configure_dsi_pll(encoder)) {
+ DRM_ERROR("Configure DSI PLL failed, abort PLL enable\n");
+ return;
+ }
+
+ /* Enable DSI PLL */
+ val = I915_READ(BXT_DSI_PLL_ENABLE);
+ val |= BXT_DSI_PLL_DO_ENABLE;
+ I915_WRITE(BXT_DSI_PLL_ENABLE, val);
+
+ /* Timeout and fail if PLL not locked */
+ if (wait_for(I915_READ(BXT_DSI_PLL_ENABLE) & BXT_DSI_PLL_LOCKED, 1)) {
+ DRM_ERROR("Timed out waiting for DSI PLL to lock\n");
+ return;
+ }
+
+ DRM_DEBUG_KMS("DSI PLL locked\n");
+}
+
+void intel_enable_dsi_pll(struct intel_encoder *encoder)
+{
+ struct drm_device *dev = encoder->base.dev;
+
+ if (IS_VALLEYVIEW(dev))
+ vlv_enable_dsi_pll(encoder);
+ else if (IS_BROXTON(dev))
+ bxt_enable_dsi_pll(encoder);
+}
--
1.7.9.5
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