drm/i915: Add eDP support on IGDNG mobile chip

This adds embedded DisplayPort support on next mobile chip which
aims to replace origin LVDS port. VBT's driver feature block has
been used to determine the type of current internal panel for eDP
or LVDS.

Currently no panel fitting support for eDP and backlight control
would be added in future.

Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>

drivers/gpu/drm/i915/i915_drv.h

@@ -219,6 +219,7 @@ typedef struct drm_i915_private {
 	unsigned int lvds_vbt:1;
 	unsigned int int_crt_support:1;
 	unsigned int lvds_use_ssc:1;
+	unsigned int edp_support:1;
 	int lvds_ssc_freq;
 
 	struct drm_i915_fence_reg fence_regs[16]; /* assume 965 */
@@ -889,6 +890,7 @@ extern int i915_wait_ring(struct drm_device * dev, int n, const char *caller);
 						      IS_I915GM(dev)))
 #define SUPPORTS_INTEGRATED_HDMI(dev)	(IS_G4X(dev) || IS_IGDNG(dev))
 #define SUPPORTS_INTEGRATED_DP(dev)	(IS_G4X(dev) || IS_IGDNG(dev))
+#define SUPPORTS_EDP(dev)		(IS_IGDNG_M(dev))
 #define I915_HAS_HOTPLUG(dev) (IS_I945G(dev) || IS_I945GM(dev) || IS_I965G(dev))
 /* dsparb controlled by hw only */
 #define DSPARB_HWCONTROL(dev) (IS_G4X(dev) || IS_IGDNG(dev))

drivers/gpu/drm/i915/i915_reg.h

@@ -1395,6 +1395,7 @@
 #define TV_V_CHROMA_42		0x684a8
 
 /* Display Port */
+#define DP_A				0x64000 /* eDP */
 #define DP_B				0x64100
 #define DP_C				0x64200
 #define DP_D				0x64300
@@ -1437,9 +1438,17 @@
 /* Mystic DPCD version 1.1 special mode */
 #define   DP_ENHANCED_FRAMING		(1 << 18)
 
+/* eDP */
+#define   DP_PLL_FREQ_270MHZ		(0 << 16)
+#define   DP_PLL_FREQ_160MHZ		(1 << 16)
+#define   DP_PLL_FREQ_MASK		(3 << 16)
+
 /** locked once port is enabled */
 #define   DP_PORT_REVERSAL		(1 << 15)
 
+/* eDP */
+#define   DP_PLL_ENABLE			(1 << 14)
+
 /** sends the clock on lane 15 of the PEG for debug */
 #define   DP_CLOCK_OUTPUT_ENABLE	(1 << 13)
 
@@ -1464,6 +1473,13 @@
  * is 20 bytes in each direction, hence the 5 fixed
  * data registers
  */
+#define DPA_AUX_CH_CTL			0x64010
+#define DPA_AUX_CH_DATA1		0x64014
+#define DPA_AUX_CH_DATA2		0x64018
+#define DPA_AUX_CH_DATA3		0x6401c
+#define DPA_AUX_CH_DATA4		0x64020
+#define DPA_AUX_CH_DATA5		0x64024
+
 #define DPB_AUX_CH_CTL			0x64110
 #define DPB_AUX_CH_DATA1		0x64114
 #define DPB_AUX_CH_DATA2		0x64118

drivers/gpu/drm/i915/intel_bios.c

@@ -296,6 +296,25 @@ parse_sdvo_device_mapping(struct drm_i915_private *dev_priv,
 	}
 	return;
 }
+
+static void
+parse_driver_features(struct drm_i915_private *dev_priv,
+		       struct bdb_header *bdb)
+{
+	struct drm_device *dev = dev_priv->dev;
+	struct bdb_driver_features *driver;
+
+	/* set default for chips without eDP */
+	if (!SUPPORTS_EDP(dev)) {
+		dev_priv->edp_support = 0;
+		return;
+	}
+
+	driver = find_section(bdb, BDB_DRIVER_FEATURES);
+	if (driver && driver->lvds_config == BDB_DRIVER_FEATURE_EDP)
+		dev_priv->edp_support = 1;
+}
+
 /**
  * intel_init_bios - initialize VBIOS settings & find VBT
  * @dev: DRM device
@@ -346,6 +365,8 @@ intel_init_bios(struct drm_device *dev)
 	parse_lfp_panel_data(dev_priv, bdb);
 	parse_sdvo_panel_data(dev_priv, bdb);
 	parse_sdvo_device_mapping(dev_priv, bdb);
+	parse_driver_features(dev_priv, bdb);
+
 	pci_unmap_rom(pdev, bios);
 
 	return 0;

drivers/gpu/drm/i915/intel_bios.h

@@ -381,6 +381,51 @@ struct bdb_sdvo_lvds_options {
 } __attribute__((packed));
 
 
+#define BDB_DRIVER_FEATURE_NO_LVDS		0
+#define BDB_DRIVER_FEATURE_INT_LVDS		1
+#define BDB_DRIVER_FEATURE_SDVO_LVDS		2
+#define BDB_DRIVER_FEATURE_EDP			3
+
+struct bdb_driver_features {
+	u8 boot_dev_algorithm:1;
+	u8 block_display_switch:1;
+	u8 allow_display_switch:1;
+	u8 hotplug_dvo:1;
+	u8 dual_view_zoom:1;
+	u8 int15h_hook:1;
+	u8 sprite_in_clone:1;
+	u8 primary_lfp_id:1;
+
+	u16 boot_mode_x;
+	u16 boot_mode_y;
+	u8 boot_mode_bpp;
+	u8 boot_mode_refresh;
+
+	u16 enable_lfp_primary:1;
+	u16 selective_mode_pruning:1;
+	u16 dual_frequency:1;
+	u16 render_clock_freq:1; /* 0: high freq; 1: low freq */
+	u16 nt_clone_support:1;
+	u16 power_scheme_ui:1; /* 0: CUI; 1: 3rd party */
+	u16 sprite_display_assign:1; /* 0: secondary; 1: primary */
+	u16 cui_aspect_scaling:1;
+	u16 preserve_aspect_ratio:1;
+	u16 sdvo_device_power_down:1;
+	u16 crt_hotplug:1;
+	u16 lvds_config:2;
+	u16 tv_hotplug:1;
+	u16 hdmi_config:2;
+
+	u8 static_display:1;
+	u8 reserved2:7;
+	u16 legacy_crt_max_x;
+	u16 legacy_crt_max_y;
+	u8 legacy_crt_max_refresh;
+
+	u8 hdmi_termination;
+	u8 custom_vbt_version;
+} __attribute__((packed));
+
 bool intel_init_bios(struct drm_device *dev);
 
 /*