[Intel-gfx] [PATCH] drm/i915/bxt: Bring MIPI out of reset

[Bob Paauwe]

and power up the DSI regulator when initializing a MIPI display.

Signed-off-by: Bob Paauwe <bob.j.paauwe at intel.com>
---
 drivers/gpu/drm/i915/i915_reg.h  |  8 ++++++++
 drivers/gpu/drm/i915/intel_dsi.c | 13 +++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 6607aaf..da29d74 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -1262,11 +1262,19 @@ enum skl_disp_power_wells {
 #define CHV_TX_DW14(ch, lane) _TXLANE(ch, lane, 0xb8)
 #define   DPIO_UPAR_SHIFT		30
 
+/* BXT DSI Regulator registers */
+#define BXT_DSI_CFG                    _MMIO(0x160020)
+#define   STRAP_SELECT                 (1 << 0)
+
+#define BXT_DSI_TXCNTRL                _MMIO(0x160054)
+#define   HS_IO_CONTROL_SELECT         0x0
+
 /* BXT PHY registers */
 #define _BXT_PHY(phy, a, b)		_MMIO_PIPE((phy), (a), (b))
 
 #define BXT_P_CR_GT_DISP_PWRON		_MMIO(0x138090)
 #define   GT_DISPLAY_POWER_ON(phy)	(1 << (phy))
+#define   MIPIO_RST_CTRL                (1 << 2)
 
 #define _PHY_CTL_FAMILY_EDP		0x64C80
 #define _PHY_CTL_FAMILY_DDI		0x64C90
diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
index b2d2cba..c2aa9e1 100644
--- a/drivers/gpu/drm/i915/intel_dsi.c
+++ b/drivers/gpu/drm/i915/intel_dsi.c
@@ -549,6 +549,19 @@ static void intel_dsi_pre_enable(struct intel_encoder *encoder)
 		I915_WRITE(DSPCLK_GATE_D, tmp);
 	}
 
+	if (IS_BROXTON(dev)) {
+		/*
+		 * Bring the MIPI IO out of reset and power up
+		 * the DSI regulator.
+		 */
+		tmp = I915_READ(BXT_P_CR_GT_DISP_PWRON);
+		tmp |= MIPIO_RST_CTRL;
+		I915_WRITE(BXT_P_CR_GT_DISP_PWRON, tmp);
+
+		I915_WRITE(BXT_DSI_CFG, STRAP_SELECT);
+		I915_WRITE(BXT_DSI_TXCNTRL, HS_IO_CONTROL_SELECT);
+	}
+
 	/* put device in ready state */
 	intel_dsi_device_ready(encoder);
 
-- 
2.7.4