From: Paulo Zanoni <paulo.r.zanoni at intel.com>
Now it implements 3 different sequences from BSpec and also has
support for ULT.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni at intel.com>
---
drivers/gpu/drm/i915/i915_reg.h | 2 ++
drivers/gpu/drm/i915/intel_display.c | 41 +++++++++++++++++++++++++-----------
2 files changed, 31 insertions(+), 12 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index dc3d6a7..be6164f 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -4863,6 +4863,8 @@
#define SBI_SSCAUXDIV_FINALDIV2SEL(x) ((x)<<4)
#define SBI_DBUFF0 0x2a00
#define SBI_DBUFF0_ENABLE (1<<0)
+#define SBI_GEN0 0x1f00
+#define SBI_GEN0_ENABLE (1<<0)
/* LPT PIXCLK_GATE */
#define PIXCLK_GATE 0xC6020
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index f4c5263..5f3b636 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -5258,12 +5258,20 @@ static void lpt_program_fdi_mphy(struct drm_i915_private *dev_priv)
intel_sbi_write(dev_priv, 0x21EC, tmp, SBI_MPHY);
}
-/* Sequence to enable CLKOUT_DP for FDI usage and configure PCH FDI I/O. */
-static void lpt_enable_clkout_dp(struct drm_device *dev)
+/* Implements 3 different sequences from BSpec chapter "Display iCLK
+ * Programming" based on the parameters passed:
+ * - Sequence to enable CLKOUT_DP
+ * - Sequence to enable CLKOUT_DP without spread
+ * - Sequence to enable CLKOUT_DP for FDI usage and configure PCH FDI I/O
+ */
+static void lpt_enable_clkout_dp(struct drm_device *dev, bool with_spread,
+ bool with_fdi)
{
struct drm_i915_private *dev_priv = dev->dev_private;
uint32_t tmp;
+ WARN(with_fdi && !with_spread, "FDI requires downspread\n");
+
mutex_lock(&dev_priv->dpio_lock);
tmp = intel_sbi_read(dev_priv, SBI_SSCCTL, SBI_ICLK);
@@ -5273,17 +5281,26 @@ static void lpt_enable_clkout_dp(struct drm_device *dev)
udelay(24);
- tmp = intel_sbi_read(dev_priv, SBI_SSCCTL, SBI_ICLK);
- tmp &= ~SBI_SSCCTL_PATHALT;
- intel_sbi_write(dev_priv, SBI_SSCCTL, tmp, SBI_ICLK);
+ if (with_spread) {
+ tmp = intel_sbi_read(dev_priv, SBI_SSCCTL, SBI_ICLK);
+ tmp &= ~SBI_SSCCTL_PATHALT;
+ intel_sbi_write(dev_priv, SBI_SSCCTL, tmp, SBI_ICLK);
- lpt_reset_fdi_mphy(dev_priv);
- lpt_program_fdi_mphy(dev_priv);
+ if (with_fdi) {
+ lpt_reset_fdi_mphy(dev_priv);
+ lpt_program_fdi_mphy(dev_priv);
+ }
+ }
- /* ULT uses SBI_GEN0, but ULT doesn't have VGA, so we don't care. */
- tmp = intel_sbi_read(dev_priv, SBI_DBUFF0, SBI_ICLK);
- tmp |= SBI_DBUFF0_ENABLE;
- intel_sbi_write(dev_priv, SBI_DBUFF0, tmp, SBI_ICLK);
+ if (IS_ULT(dev)) {
+ tmp = intel_sbi_read(dev_priv, SBI_GEN0, SBI_ICLK);
+ tmp |= SBI_GEN0_ENABLE;
+ intel_sbi_write(dev_priv, SBI_GEN0, tmp, SBI_ICLK);
+ } else {
+ tmp = intel_sbi_read(dev_priv, SBI_DBUFF0, SBI_ICLK);
+ tmp |= SBI_DBUFF0_ENABLE;
+ intel_sbi_write(dev_priv, SBI_DBUFF0, tmp, SBI_ICLK);
+ }
mutex_unlock(&dev_priv->dpio_lock);
}
@@ -5305,7 +5322,7 @@ static void lpt_init_pch_refclk(struct drm_device *dev)
if (!has_vga)
return;
- lpt_enable_clkout_dp(dev);
+ lpt_enable_clkout_dp(dev, true, true);
}
/*
--
1.8.1.2
