drm/tilcdc: support pixel widths greater than 1024

TI LCD controller version 2 has an extended eleventh
bit that enables horizontal resolutions greater than
1024 pixels to be specified (upto 2048).  This patch
adds support for setting this bit on LCDC V2.

Signed-off-by: Darren Etheridge <detheridge@ti.com>
Acked-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

2 files changed, 16 insertions, 0 deletions

diff --git a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c
index 4de3fb4246fc..5b68fe59e437 100644
--- a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c
+++ b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c
@@ -310,6 +310,21 @@ static int tilcdc_crtc_mode_set(struct drm_crtc *crtc,
                 ((vsw & 0x3f) << 10);
         tilcdc_write(dev, LCDC_RASTER_TIMING_1_REG, reg);
 
+        /*
+         * be sure to set Bit 10 for the V2 LCDC controller,
+         * otherwise limited to 1024 pixels width, stopping
+         * 1920x1080 being suppoted.
+         */
+        if (priv->rev == 2) {
+                if ((mode->vdisplay - 1) & 0x400) {
+                        tilcdc_set(dev, LCDC_RASTER_TIMING_2_REG,
+                                LCDC_LPP_B10);
+                } else {
+                        tilcdc_clear(dev, LCDC_RASTER_TIMING_2_REG,
+                                LCDC_LPP_B10);
+                }
+        }
+
         /* Configure display type: */
         reg = tilcdc_read(dev, LCDC_RASTER_CTRL_REG) &
                 ~(LCDC_TFT_MODE | LCDC_MONO_8BIT_MODE | LCDC_MONOCHROME_MODE |
diff --git a/drivers/gpu/drm/tilcdc/tilcdc_regs.h b/drivers/gpu/drm/tilcdc/tilcdc_regs.h
index 17fd1b45428a..1bf5e2553acc 100644
--- a/drivers/gpu/drm/tilcdc/tilcdc_regs.h
+++ b/drivers/gpu/drm/tilcdc/tilcdc_regs.h
@@ -80,6 +80,7 @@
 #define LCDC_INVERT_PIXEL_CLOCK                  BIT(22)
 #define LCDC_INVERT_HSYNC                        BIT(21)
 #define LCDC_INVERT_VSYNC                        BIT(20)
+#define LCDC_LPP_B10                             BIT(26)
 
 /* LCDC Block */
 #define LCDC_PID_REG                             0x0