drm/tegra: Add plane support

Add support for the B and C planes which support RGB and YUV pixel
formats and can be used as overlays or hardware cursor. Currently 32-bit
XRGB as well as UYVY, YUV420 and YUV422 pixel formats are advertised.
Other formats should be easy to add but these are the most common ones
and should cover the majority of use-cases.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
diff --git a/drivers/gpu/drm/tegra/dc.c b/drivers/gpu/drm/tegra/dc.c
index d35ff8b..52bf63f 100644
--- a/drivers/gpu/drm/tegra/dc.c
+++ b/drivers/gpu/drm/tegra/dc.c
@@ -18,26 +18,143 @@
 #include "drm.h"
 #include "dc.h"
 
-struct tegra_dc_window {
-	fixed20_12 x;
-	fixed20_12 y;
-	fixed20_12 w;
-	fixed20_12 h;
-	unsigned int outx;
-	unsigned int outy;
-	unsigned int outw;
-	unsigned int outh;
-	unsigned int stride;
-	unsigned int fmt;
+struct tegra_plane {
+	struct drm_plane base;
+	unsigned int index;
 };
 
+static inline struct tegra_plane *to_tegra_plane(struct drm_plane *plane)
+{
+	return container_of(plane, struct tegra_plane, base);
+}
+
+static int tegra_plane_update(struct drm_plane *plane, struct drm_crtc *crtc,
+			      struct drm_framebuffer *fb, int crtc_x,
+			      int crtc_y, unsigned int crtc_w,
+			      unsigned int crtc_h, uint32_t src_x,
+			      uint32_t src_y, uint32_t src_w, uint32_t src_h)
+{
+	struct tegra_plane *p = to_tegra_plane(plane);
+	struct tegra_dc *dc = to_tegra_dc(crtc);
+	struct tegra_dc_window window;
+	unsigned int i;
+
+	memset(&window, 0, sizeof(window));
+	window.src.x = src_x >> 16;
+	window.src.y = src_y >> 16;
+	window.src.w = src_w >> 16;
+	window.src.h = src_h >> 16;
+	window.dst.x = crtc_x;
+	window.dst.y = crtc_y;
+	window.dst.w = crtc_w;
+	window.dst.h = crtc_h;
+	window.format = tegra_dc_format(fb->pixel_format);
+	window.bits_per_pixel = fb->bits_per_pixel;
+
+	for (i = 0; i < drm_format_num_planes(fb->pixel_format); i++) {
+		struct drm_gem_cma_object *gem = drm_fb_cma_get_gem_obj(fb, i);
+
+		window.base[i] = gem->paddr + fb->offsets[i];
+
+		/*
+		 * Tegra doesn't support different strides for U and V planes
+		 * so we display a warning if the user tries to display a
+		 * framebuffer with such a configuration.
+		 */
+		if (i >= 2) {
+			if (fb->pitches[i] != window.stride[1])
+				DRM_ERROR("unsupported UV-plane configuration\n");
+		} else {
+			window.stride[i] = fb->pitches[i];
+		}
+	}
+
+	return tegra_dc_setup_window(dc, p->index, &window);
+}
+
+static int tegra_plane_disable(struct drm_plane *plane)
+{
+	struct tegra_dc *dc = to_tegra_dc(plane->crtc);
+	struct tegra_plane *p = to_tegra_plane(plane);
+	unsigned long value;
+
+	value = WINDOW_A_SELECT << p->index;
+	tegra_dc_writel(dc, value, DC_CMD_DISPLAY_WINDOW_HEADER);
+
+	value = tegra_dc_readl(dc, DC_WIN_WIN_OPTIONS);
+	value &= ~WIN_ENABLE;
+	tegra_dc_writel(dc, value, DC_WIN_WIN_OPTIONS);
+
+	tegra_dc_writel(dc, WIN_A_UPDATE << p->index, DC_CMD_STATE_CONTROL);
+	tegra_dc_writel(dc, WIN_A_ACT_REQ << p->index, DC_CMD_STATE_CONTROL);
+
+	return 0;
+}
+
+static void tegra_plane_destroy(struct drm_plane *plane)
+{
+	tegra_plane_disable(plane);
+	drm_plane_cleanup(plane);
+}
+
+static const struct drm_plane_funcs tegra_plane_funcs = {
+	.update_plane = tegra_plane_update,
+	.disable_plane = tegra_plane_disable,
+	.destroy = tegra_plane_destroy,
+};
+
+static const uint32_t plane_formats[] = {
+	DRM_FORMAT_XRGB8888,
+	DRM_FORMAT_UYVY,
+	DRM_FORMAT_YUV420,
+	DRM_FORMAT_YUV422,
+};
+
+static int tegra_dc_add_planes(struct drm_device *drm, struct tegra_dc *dc)
+{
+	unsigned int i;
+	int err = 0;
+
+	for (i = 0; i < 2; i++) {
+		struct tegra_plane *plane;
+
+		plane = devm_kzalloc(drm->dev, sizeof(*plane), GFP_KERNEL);
+		if (!plane)
+			return -ENOMEM;
+
+		plane->index = 1 + i;
+
+		err = drm_plane_init(drm, &plane->base, 1 << dc->pipe,
+				     &tegra_plane_funcs, plane_formats,
+				     ARRAY_SIZE(plane_formats), false);
+		if (err < 0)
+			return err;
+	}
+
+	return 0;
+}
+
 static const struct drm_crtc_funcs tegra_crtc_funcs = {
 	.set_config = drm_crtc_helper_set_config,
 	.destroy = drm_crtc_cleanup,
 };
 
-static void tegra_crtc_dpms(struct drm_crtc *crtc, int mode)
+static void tegra_crtc_disable(struct drm_crtc *crtc)
 {
+	struct drm_device *drm = crtc->dev;
+	struct drm_plane *plane;
+
+	list_for_each_entry(plane, &drm->mode_config.plane_list, head) {
+		if (plane->crtc == crtc) {
+			tegra_plane_disable(plane);
+			plane->crtc = NULL;
+
+			if (plane->fb) {
+				drm_framebuffer_unreference(plane->fb);
+				plane->fb = NULL;
+			}
+		}
+	}
 }
 
 static bool tegra_crtc_mode_fixup(struct drm_crtc *crtc,
@@ -47,10 +164,11 @@
 	return true;
 }
 
-static inline u32 compute_dda_inc(fixed20_12 inf, unsigned int out, bool v,
+static inline u32 compute_dda_inc(unsigned int in, unsigned int out, bool v,
 				  unsigned int bpp)
 {
 	fixed20_12 outf = dfixed_init(out);
+	fixed20_12 inf = dfixed_init(in);
 	u32 dda_inc;
 	int max;
 
@@ -80,9 +198,10 @@
 	return dda_inc;
 }
 
-static inline u32 compute_initial_dda(fixed20_12 in)
+static inline u32 compute_initial_dda(unsigned int in)
 {
-	return dfixed_frac(in);
+	fixed20_12 inf = dfixed_init(in);
+	return dfixed_frac(inf);
 }
 
 static int tegra_dc_set_timings(struct tegra_dc *dc,
@@ -153,6 +272,185 @@
 	return 0;
 }
 
+static bool tegra_dc_format_is_yuv(unsigned int format, bool *planar)
+{
+	switch (format) {
+	case WIN_COLOR_DEPTH_YCbCr422:
+	case WIN_COLOR_DEPTH_YUV422:
+		if (planar)
+			*planar = false;
+
+		return true;
+
+	case WIN_COLOR_DEPTH_YCbCr420P:
+	case WIN_COLOR_DEPTH_YUV420P:
+	case WIN_COLOR_DEPTH_YCbCr422P:
+	case WIN_COLOR_DEPTH_YUV422P:
+	case WIN_COLOR_DEPTH_YCbCr422R:
+	case WIN_COLOR_DEPTH_YUV422R:
+	case WIN_COLOR_DEPTH_YCbCr422RA:
+	case WIN_COLOR_DEPTH_YUV422RA:
+		if (planar)
+			*planar = true;
+
+		return true;
+	}
+
+	return false;
+}
+
+int tegra_dc_setup_window(struct tegra_dc *dc, unsigned int index,
+			  const struct tegra_dc_window *window)
+{
+	unsigned h_offset, v_offset, h_size, v_size, h_dda, v_dda, bpp;
+	unsigned long value;
+	bool yuv, planar;
+
+	/*
+	 * For YUV planar modes, the number of bytes per pixel takes into
+	 * account only the luma component and therefore is 1.
+	 */
+	yuv = tegra_dc_format_is_yuv(window->format, &planar);
+	if (!yuv)
+		bpp = window->bits_per_pixel / 8;
+	else
+		bpp = planar ? 1 : 2;
+
+	value = WINDOW_A_SELECT << index;
+	tegra_dc_writel(dc, value, DC_CMD_DISPLAY_WINDOW_HEADER);
+
+	tegra_dc_writel(dc, window->format, DC_WIN_COLOR_DEPTH);
+	tegra_dc_writel(dc, 0, DC_WIN_BYTE_SWAP);
+
+	value = V_POSITION(window->dst.y) | H_POSITION(window->dst.x);
+	tegra_dc_writel(dc, value, DC_WIN_POSITION);
+
+	value = V_SIZE(window->dst.h) | H_SIZE(window->dst.w);
+	tegra_dc_writel(dc, value, DC_WIN_SIZE);
+
+	h_offset = window->src.x * bpp;
+	v_offset = window->src.y;
+	h_size = window->src.w * bpp;
+	v_size = window->src.h;
+
+	value = V_PRESCALED_SIZE(v_size) | H_PRESCALED_SIZE(h_size);
+	tegra_dc_writel(dc, value, DC_WIN_PRESCALED_SIZE);
+
+	/*
+	 * For DDA computations the number of bytes per pixel for YUV planar
+	 * modes needs to take into account all Y, U and V components.
+	 */
+	if (yuv && planar)
+		bpp = 2;
+
+	h_dda = compute_dda_inc(window->src.w, window->dst.w, false, bpp);
+	v_dda = compute_dda_inc(window->src.h, window->dst.h, true, bpp);
+
+	value = V_DDA_INC(v_dda) | H_DDA_INC(h_dda);
+	tegra_dc_writel(dc, value, DC_WIN_DDA_INC);
+
+	h_dda = compute_initial_dda(window->src.x);
+	v_dda = compute_initial_dda(window->src.y);
+
+	tegra_dc_writel(dc, h_dda, DC_WIN_H_INITIAL_DDA);
+	tegra_dc_writel(dc, v_dda, DC_WIN_V_INITIAL_DDA);
+
+	tegra_dc_writel(dc, 0, DC_WIN_UV_BUF_STRIDE);
+	tegra_dc_writel(dc, 0, DC_WIN_BUF_STRIDE);
+
+	tegra_dc_writel(dc, window->base[0], DC_WINBUF_START_ADDR);
+
+	if (yuv && planar) {
+		tegra_dc_writel(dc, window->base[1], DC_WINBUF_START_ADDR_U);
+		tegra_dc_writel(dc, window->base[2], DC_WINBUF_START_ADDR_V);
+		value = window->stride[1] << 16 | window->stride[0];
+		tegra_dc_writel(dc, value, DC_WIN_LINE_STRIDE);
+	} else {
+		tegra_dc_writel(dc, window->stride[0], DC_WIN_LINE_STRIDE);
+	}
+
+	tegra_dc_writel(dc, h_offset, DC_WINBUF_ADDR_H_OFFSET);
+	tegra_dc_writel(dc, v_offset, DC_WINBUF_ADDR_V_OFFSET);
+
+	value = WIN_ENABLE;
+
+	if (yuv) {
+		/* setup default colorspace conversion coefficients */
+		tegra_dc_writel(dc, 0x00f0, DC_WIN_CSC_YOF);
+		tegra_dc_writel(dc, 0x012a, DC_WIN_CSC_KYRGB);
+		tegra_dc_writel(dc, 0x0000, DC_WIN_CSC_KUR);
+		tegra_dc_writel(dc, 0x0198, DC_WIN_CSC_KVR);
+		tegra_dc_writel(dc, 0x039b, DC_WIN_CSC_KUG);
+		tegra_dc_writel(dc, 0x032f, DC_WIN_CSC_KVG);
+		tegra_dc_writel(dc, 0x0204, DC_WIN_CSC_KUB);
+		tegra_dc_writel(dc, 0x0000, DC_WIN_CSC_KVB);
+
+		value |= CSC_ENABLE;
+	} else if (bpp < 24) {
+		value |= COLOR_EXPAND;
+	}
+
+	tegra_dc_writel(dc, value, DC_WIN_WIN_OPTIONS);
+
+	/*
+	 * Disable blending and assume Window A is the bottom-most window,
+	 * Window C is the top-most window and Window B is in the middle.
+	 */
+	tegra_dc_writel(dc, 0xffff00, DC_WIN_BLEND_NOKEY);
+	tegra_dc_writel(dc, 0xffff00, DC_WIN_BLEND_1WIN);
+
+	switch (index) {
+	case 0:
+		tegra_dc_writel(dc, 0x000000, DC_WIN_BLEND_2WIN_X);
+		tegra_dc_writel(dc, 0x000000, DC_WIN_BLEND_2WIN_Y);
+		tegra_dc_writel(dc, 0x000000, DC_WIN_BLEND_3WIN_XY);
+		break;
+
+	case 1:
+		tegra_dc_writel(dc, 0xffff00, DC_WIN_BLEND_2WIN_X);
+		tegra_dc_writel(dc, 0x000000, DC_WIN_BLEND_2WIN_Y);
+		tegra_dc_writel(dc, 0x000000, DC_WIN_BLEND_3WIN_XY);
+		break;
+
+	case 2:
+		tegra_dc_writel(dc, 0xffff00, DC_WIN_BLEND_2WIN_X);
+		tegra_dc_writel(dc, 0xffff00, DC_WIN_BLEND_2WIN_Y);
+		tegra_dc_writel(dc, 0xffff00, DC_WIN_BLEND_3WIN_XY);
+		break;
+	}
+
+	tegra_dc_writel(dc, WIN_A_UPDATE << index, DC_CMD_STATE_CONTROL);
+	tegra_dc_writel(dc, WIN_A_ACT_REQ << index, DC_CMD_STATE_CONTROL);
+
+	return 0;
+}
+
+unsigned int tegra_dc_format(uint32_t format)
+{
+	switch (format) {
+	case DRM_FORMAT_XRGB8888:
+		return WIN_COLOR_DEPTH_B8G8R8A8;
+
+	case DRM_FORMAT_RGB565:
+		return WIN_COLOR_DEPTH_B5G6R5;
+
+	case DRM_FORMAT_UYVY:
+		return WIN_COLOR_DEPTH_YCbCr422;
+
+	case DRM_FORMAT_YUV420:
+		return WIN_COLOR_DEPTH_YCbCr420P;
+
+	case DRM_FORMAT_YUV422:
+		return WIN_COLOR_DEPTH_YCbCr422P;
+
+	default:
+		break;
+	}
+
+	WARN(1, "unsupported pixel format %u, using default\n", format);
+	return WIN_COLOR_DEPTH_B8G8R8A8;
+}
+
 static int tegra_crtc_mode_set(struct drm_crtc *crtc,
 			       struct drm_display_mode *mode,
 			       struct drm_display_mode *adjusted,
@@ -160,8 +458,7 @@
 {
 	struct drm_gem_cma_object *gem = drm_fb_cma_get_gem_obj(crtc->fb, 0);
 	struct tegra_dc *dc = to_tegra_dc(crtc);
-	unsigned int h_dda, v_dda, bpp;
-	struct tegra_dc_window win;
+	struct tegra_dc_window window;
 	unsigned long div, value;
 	int err;
 
@@ -192,81 +489,23 @@
 	tegra_dc_writel(dc, value, DC_DISP_DISP_CLOCK_CONTROL);
 
 	/* setup window parameters */
-	memset(&win, 0, sizeof(win));
-	win.x.full = dfixed_const(0);
-	win.y.full = dfixed_const(0);
-	win.w.full = dfixed_const(mode->hdisplay);
-	win.h.full = dfixed_const(mode->vdisplay);
-	win.outx = 0;
-	win.outy = 0;
-	win.outw = mode->hdisplay;
-	win.outh = mode->vdisplay;
+	memset(&window, 0, sizeof(window));
+	window.src.x = 0;
+	window.src.y = 0;
+	window.src.w = mode->hdisplay;
+	window.src.h = mode->vdisplay;
+	window.dst.x = 0;
+	window.dst.y = 0;
+	window.dst.w = mode->hdisplay;
+	window.dst.h = mode->vdisplay;
+	window.format = tegra_dc_format(crtc->fb->pixel_format);
+	window.bits_per_pixel = crtc->fb->bits_per_pixel;
+	window.stride[0] = crtc->fb->pitches[0];
+	window.base[0] = gem->paddr;
 
-	switch (crtc->fb->pixel_format) {
-	case DRM_FORMAT_XRGB8888:
-		win.fmt = WIN_COLOR_DEPTH_B8G8R8A8;
-		break;
-
-	case DRM_FORMAT_RGB565:
-		win.fmt = WIN_COLOR_DEPTH_B5G6R5;
-		break;
-
-	default:
-		win.fmt = WIN_COLOR_DEPTH_B8G8R8A8;
-		WARN_ON(1);
-		break;
-	}
-
-	bpp = crtc->fb->bits_per_pixel / 8;
-	win.stride = crtc->fb->pitches[0];
-
-	/* program window registers */
-	value = WINDOW_A_SELECT;
-	tegra_dc_writel(dc, value, DC_CMD_DISPLAY_WINDOW_HEADER);
-
-	tegra_dc_writel(dc, win.fmt, DC_WIN_COLOR_DEPTH);
-	tegra_dc_writel(dc, 0, DC_WIN_BYTE_SWAP);
-
-	value = V_POSITION(win.outy) | H_POSITION(win.outx);
-	tegra_dc_writel(dc, value, DC_WIN_POSITION);
-
-	value = V_SIZE(win.outh) | H_SIZE(win.outw);
-	tegra_dc_writel(dc, value, DC_WIN_SIZE);
-
-	value = V_PRESCALED_SIZE(dfixed_trunc(win.h)) |
-		H_PRESCALED_SIZE(dfixed_trunc(win.w) * bpp);
-	tegra_dc_writel(dc, value, DC_WIN_PRESCALED_SIZE);
-
-	h_dda = compute_dda_inc(win.w, win.outw, false, bpp);
-	v_dda = compute_dda_inc(win.h, win.outh, true, bpp);
-
-	value = V_DDA_INC(v_dda) | H_DDA_INC(h_dda);
-	tegra_dc_writel(dc, value, DC_WIN_DDA_INC);
-
-	h_dda = compute_initial_dda(win.x);
-	v_dda = compute_initial_dda(win.y);
-
-	tegra_dc_writel(dc, h_dda, DC_WIN_H_INITIAL_DDA);
-	tegra_dc_writel(dc, v_dda, DC_WIN_V_INITIAL_DDA);
-
-	tegra_dc_writel(dc, 0, DC_WIN_UV_BUF_STRIDE);
-	tegra_dc_writel(dc, 0, DC_WIN_BUF_STRIDE);
-
-	tegra_dc_writel(dc, fb->obj->paddr, DC_WINBUF_START_ADDR);
-	tegra_dc_writel(dc, win.stride, DC_WIN_LINE_STRIDE);
-	tegra_dc_writel(dc, dfixed_trunc(win.x) * bpp,
-			DC_WINBUF_ADDR_H_OFFSET);
-	tegra_dc_writel(dc, dfixed_trunc(win.y), DC_WINBUF_ADDR_V_OFFSET);
-
-	value = WIN_ENABLE;
-
-	if (bpp < 24)
-		value |= COLOR_EXPAND;
-
-	tegra_dc_writel(dc, value, DC_WIN_WIN_OPTIONS);
-
-	tegra_dc_writel(dc, 0xff00, DC_WIN_BLEND_NOKEY);
-	tegra_dc_writel(dc, 0xff00, DC_WIN_BLEND_1WIN);
+	err = tegra_dc_setup_window(dc, 0, &window);
+	if (err < 0)
+		dev_err(dc->dev, "failed to enable root plane\n");
 
 	return 0;
 }
@@ -347,7 +586,7 @@
 }
 
 static const struct drm_crtc_helper_funcs tegra_crtc_helper_funcs = {
-	.dpms = tegra_crtc_dpms,
+	.disable = tegra_crtc_disable,
 	.mode_fixup = tegra_crtc_mode_fixup,
 	.mode_set = tegra_crtc_mode_set,
 	.prepare = tegra_crtc_prepare,
@@ -588,7 +827,7 @@
 	DUMP_REG(DC_WIN_BLEND_1WIN);
 	DUMP_REG(DC_WIN_BLEND_2WIN_X);
 	DUMP_REG(DC_WIN_BLEND_2WIN_Y);
-	DUMP_REG(DC_WIN_BLEND32WIN_XY);
+	DUMP_REG(DC_WIN_BLEND_3WIN_XY);
 	DUMP_REG(DC_WIN_HP_FETCH_CONTROL);
 	DUMP_REG(DC_WINBUF_START_ADDR);
 	DUMP_REG(DC_WINBUF_START_ADDR_NS);
@@ -690,6 +929,10 @@
 		return err;
 	}
 
+	err = tegra_dc_add_planes(drm, dc);
+	if (err < 0)
+		return err;
+
 	if (IS_ENABLED(CONFIG_DEBUG_FS)) {
 		err = tegra_dc_debugfs_init(dc, drm->primary);
 		if (err < 0)