drm/sun4i: abstract a engine type

As we are going to add support for the Allwinner DE2 engine in sun4i-drm
driver, we will finally have two types of display engines -- the DE1
backend and the DE2 mixer. They both do some display blending and feed
graphics data to TCON, and is part of the "Display Engine" called by
Allwinner, so I choose to call them both "engine" here.

Abstract the engine type to a new struct with an ops struct, which contains
functions that should be called outside the engine-specified code (in
TCON, CRTC or TV Encoder code).

In order to preserve bisectability, we also switch the backend and layer
code in its own module.

Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

drivers/gpu/drm/sun4i/Makefile

@@ -5,9 +5,10 @@ sun4i-tcon-y += sun4i_tcon.o
 sun4i-tcon-y += sun4i_rgb.o
 sun4i-tcon-y += sun4i_dotclock.o
 sun4i-tcon-y += sun4i_crtc.o
-sun4i-tcon-y += sun4i_layer.o
+
+sun4i-backend-y += sun4i_backend.o sun4i_layer.o
 
 obj-$(CONFIG_DRM_SUN4I)		+= sun4i-drm.o sun4i-tcon.o
-obj-$(CONFIG_DRM_SUN4I)		+= sun4i_backend.o
+obj-$(CONFIG_DRM_SUN4I)		+= sun4i-backend.o
 obj-$(CONFIG_DRM_SUN4I)		+= sun6i_drc.o
 obj-$(CONFIG_DRM_SUN4I)		+= sun4i_tv.o

drivers/gpu/drm/sun4i/sun4i_backend.c

@@ -25,48 +25,47 @@
 
 #include "sun4i_backend.h"
 #include "sun4i_drv.h"
+#include "sun4i_layer.h"
+#include "sunxi_engine.h"
 
 static const u32 sunxi_rgb2yuv_coef[12] = {
 	0x00000107, 0x00000204, 0x00000064, 0x00000108,
 	0x00003f69, 0x00003ed6, 0x000001c1, 0x00000808,
 	0x000001c1, 0x00003e88, 0x00003fb8, 0x00000808
 };
 
-void sun4i_backend_apply_color_correction(struct sun4i_backend *backend)
+static void sun4i_backend_apply_color_correction(struct sunxi_engine *engine)
 {
 	int i;
 
 	DRM_DEBUG_DRIVER("Applying RGB to YUV color correction\n");
 
 	/* Set color correction */
-	regmap_write(backend->regs, SUN4I_BACKEND_OCCTL_REG,
+	regmap_write(engine->regs, SUN4I_BACKEND_OCCTL_REG,
 		     SUN4I_BACKEND_OCCTL_ENABLE);
 
 	for (i = 0; i < 12; i++)
-		regmap_write(backend->regs, SUN4I_BACKEND_OCRCOEF_REG(i),
+		regmap_write(engine->regs, SUN4I_BACKEND_OCRCOEF_REG(i),
 			     sunxi_rgb2yuv_coef[i]);
 }
-EXPORT_SYMBOL(sun4i_backend_apply_color_correction);
 
-void sun4i_backend_disable_color_correction(struct sun4i_backend *backend)
+static void sun4i_backend_disable_color_correction(struct sunxi_engine *engine)
 {
 	DRM_DEBUG_DRIVER("Disabling color correction\n");
 
 	/* Disable color correction */
-	regmap_update_bits(backend->regs, SUN4I_BACKEND_OCCTL_REG,
+	regmap_update_bits(engine->regs, SUN4I_BACKEND_OCCTL_REG,
 			   SUN4I_BACKEND_OCCTL_ENABLE, 0);
 }
-EXPORT_SYMBOL(sun4i_backend_disable_color_correction);
 
-void sun4i_backend_commit(struct sun4i_backend *backend)
+static void sun4i_backend_commit(struct sunxi_engine *engine)
 {
 	DRM_DEBUG_DRIVER("Committing changes\n");
 
-	regmap_write(backend->regs, SUN4I_BACKEND_REGBUFFCTL_REG,
+	regmap_write(engine->regs, SUN4I_BACKEND_REGBUFFCTL_REG,
 		     SUN4I_BACKEND_REGBUFFCTL_AUTOLOAD_DIS |
 		     SUN4I_BACKEND_REGBUFFCTL_LOADCTL);
 }
-EXPORT_SYMBOL(sun4i_backend_commit);
 
 void sun4i_backend_layer_enable(struct sun4i_backend *backend,
 				int layer, bool enable)
@@ -81,10 +80,9 @@ void sun4i_backend_layer_enable(struct sun4i_backend *backend,
 	else
 		val = 0;
 
-	regmap_update_bits(backend->regs, SUN4I_BACKEND_MODCTL_REG,
+	regmap_update_bits(backend->engine.regs, SUN4I_BACKEND_MODCTL_REG,
 			   SUN4I_BACKEND_MODCTL_LAY_EN(layer), val);
 }
-EXPORT_SYMBOL(sun4i_backend_layer_enable);
 
 static int sun4i_backend_drm_format_to_layer(struct drm_plane *plane,
 					     u32 format, u32 *mode)
@@ -144,33 +142,33 @@ int sun4i_backend_update_layer_coord(struct sun4i_backend *backend,
 	if (plane->type == DRM_PLANE_TYPE_PRIMARY) {
 		DRM_DEBUG_DRIVER("Primary layer, updating global size W: %u H: %u\n",
 				 state->crtc_w, state->crtc_h);
-		regmap_write(backend->regs, SUN4I_BACKEND_DISSIZE_REG,
+		regmap_write(backend->engine.regs, SUN4I_BACKEND_DISSIZE_REG,
 			     SUN4I_BACKEND_DISSIZE(state->crtc_w,
 						   state->crtc_h));
 	}
 
 	/* Set the line width */
 	DRM_DEBUG_DRIVER("Layer line width: %d bits\n", fb->pitches[0] * 8);
-	regmap_write(backend->regs, SUN4I_BACKEND_LAYLINEWIDTH_REG(layer),
+	regmap_write(backend->engine.regs,
+		     SUN4I_BACKEND_LAYLINEWIDTH_REG(layer),
 		     fb->pitches[0] * 8);
 
 	/* Set height and width */
 	DRM_DEBUG_DRIVER("Layer size W: %u H: %u\n",
 			 state->crtc_w, state->crtc_h);
-	regmap_write(backend->regs, SUN4I_BACKEND_LAYSIZE_REG(layer),
+	regmap_write(backend->engine.regs, SUN4I_BACKEND_LAYSIZE_REG(layer),
 		     SUN4I_BACKEND_LAYSIZE(state->crtc_w,
 					   state->crtc_h));
 
 	/* Set base coordinates */
 	DRM_DEBUG_DRIVER("Layer coordinates X: %d Y: %d\n",
 			 state->crtc_x, state->crtc_y);
-	regmap_write(backend->regs, SUN4I_BACKEND_LAYCOOR_REG(layer),
+	regmap_write(backend->engine.regs, SUN4I_BACKEND_LAYCOOR_REG(layer),
 		     SUN4I_BACKEND_LAYCOOR(state->crtc_x,
 					   state->crtc_y));
 
 	return 0;
 }
-EXPORT_SYMBOL(sun4i_backend_update_layer_coord);
 
 int sun4i_backend_update_layer_formats(struct sun4i_backend *backend,
 				       int layer, struct drm_plane *plane)
@@ -185,7 +183,7 @@ int sun4i_backend_update_layer_formats(struct sun4i_backend *backend,
 		interlaced = plane->state->crtc->state->adjusted_mode.flags
 			& DRM_MODE_FLAG_INTERLACE;
 
-	regmap_update_bits(backend->regs, SUN4I_BACKEND_MODCTL_REG,
+	regmap_update_bits(backend->engine.regs, SUN4I_BACKEND_MODCTL_REG,
 			   SUN4I_BACKEND_MODCTL_ITLMOD_EN,
 			   interlaced ? SUN4I_BACKEND_MODCTL_ITLMOD_EN : 0);
 
@@ -199,12 +197,12 @@ int sun4i_backend_update_layer_formats(struct sun4i_backend *backend,
 		return ret;
 	}
 
-	regmap_update_bits(backend->regs, SUN4I_BACKEND_ATTCTL_REG1(layer),
+	regmap_update_bits(backend->engine.regs,
+			   SUN4I_BACKEND_ATTCTL_REG1(layer),
 			   SUN4I_BACKEND_ATTCTL_REG1_LAY_FBFMT, val);
 
 	return 0;
 }
-EXPORT_SYMBOL(sun4i_backend_update_layer_formats);
 
 int sun4i_backend_update_layer_buffer(struct sun4i_backend *backend,
 				      int layer, struct drm_plane *plane)
@@ -232,19 +230,19 @@ int sun4i_backend_update_layer_buffer(struct sun4i_backend *backend,
 	/* Write the 32 lower bits of the address (in bits) */
 	lo_paddr = paddr << 3;
 	DRM_DEBUG_DRIVER("Setting address lower bits to 0x%x\n", lo_paddr);
-	regmap_write(backend->regs, SUN4I_BACKEND_LAYFB_L32ADD_REG(layer),
+	regmap_write(backend->engine.regs,
+		     SUN4I_BACKEND_LAYFB_L32ADD_REG(layer),
 		     lo_paddr);
 
 	/* And the upper bits */
 	hi_paddr = paddr >> 29;
 	DRM_DEBUG_DRIVER("Setting address high bits to 0x%x\n", hi_paddr);
-	regmap_update_bits(backend->regs, SUN4I_BACKEND_LAYFB_H4ADD_REG,
+	regmap_update_bits(backend->engine.regs, SUN4I_BACKEND_LAYFB_H4ADD_REG,
 			   SUN4I_BACKEND_LAYFB_H4ADD_MSK(layer),
 			   SUN4I_BACKEND_LAYFB_H4ADD(layer, hi_paddr));
 
 	return 0;
 }
-EXPORT_SYMBOL(sun4i_backend_update_layer_buffer);
 
 static int sun4i_backend_init_sat(struct device *dev) {
 	struct sun4i_backend *backend = dev_get_drvdata(dev);
@@ -330,6 +328,13 @@ static int sun4i_backend_of_get_id(struct device_node *node)
 	return ret;
 }
 
+static const struct sunxi_engine_ops sun4i_backend_engine_ops = {
+	.commit				= sun4i_backend_commit,
+	.layers_init			= sun4i_layers_init,
+	.apply_color_correction		= sun4i_backend_apply_color_correction,
+	.disable_color_correction	= sun4i_backend_disable_color_correction,
+};
+
 static struct regmap_config sun4i_backend_regmap_config = {
 	.reg_bits	= 32,
 	.val_bits	= 32,
@@ -353,21 +358,22 @@ static int sun4i_backend_bind(struct device *dev, struct device *master,
 		return -ENOMEM;
 	dev_set_drvdata(dev, backend);
 
-	backend->node = dev->of_node;
-	backend->id = sun4i_backend_of_get_id(dev->of_node);
-	if (backend->id < 0)
-		return backend->id;
+	backend->engine.node = dev->of_node;
+	backend->engine.ops = &sun4i_backend_engine_ops;
+	backend->engine.id = sun4i_backend_of_get_id(dev->of_node);
+	if (backend->engine.id < 0)
+		return backend->engine.id;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	regs = devm_ioremap_resource(dev, res);
 	if (IS_ERR(regs))
 		return PTR_ERR(regs);
 
-	backend->regs = devm_regmap_init_mmio(dev, regs,
-					      &sun4i_backend_regmap_config);
-	if (IS_ERR(backend->regs)) {
+	backend->engine.regs = devm_regmap_init_mmio(dev, regs,
+						     &sun4i_backend_regmap_config);
+	if (IS_ERR(backend->engine.regs)) {
 		dev_err(dev, "Couldn't create the backend regmap\n");
-		return PTR_ERR(backend->regs);
+		return PTR_ERR(backend->engine.regs);
 	}
 
 	backend->reset = devm_reset_control_get(dev, NULL);
@@ -415,18 +421,18 @@ static int sun4i_backend_bind(struct device *dev, struct device *master,
 		}
 	}
 
-	list_add_tail(&backend->list, &drv->backend_list);
+	list_add_tail(&backend->engine.list, &drv->engine_list);
 
 	/* Reset the registers */
 	for (i = 0x800; i < 0x1000; i += 4)
-		regmap_write(backend->regs, i, 0);
+		regmap_write(backend->engine.regs, i, 0);
 
 	/* Disable registers autoloading */
-	regmap_write(backend->regs, SUN4I_BACKEND_REGBUFFCTL_REG,
+	regmap_write(backend->engine.regs, SUN4I_BACKEND_REGBUFFCTL_REG,
 		     SUN4I_BACKEND_REGBUFFCTL_AUTOLOAD_DIS);
 
 	/* Enable the backend */
-	regmap_write(backend->regs, SUN4I_BACKEND_MODCTL_REG,
+	regmap_write(backend->engine.regs, SUN4I_BACKEND_MODCTL_REG,
 		     SUN4I_BACKEND_MODCTL_DEBE_EN |
 		     SUN4I_BACKEND_MODCTL_START_CTL);
 
@@ -448,7 +454,7 @@ static void sun4i_backend_unbind(struct device *dev, struct device *master,
 {
 	struct sun4i_backend *backend = dev_get_drvdata(dev);
 
-	list_del(&backend->list);
+	list_del(&backend->engine.list);
 
 	if (of_device_is_compatible(dev->of_node,
 				    "allwinner,sun8i-a33-display-backend"))

drivers/gpu/drm/sun4i/sun4i_backend.h

@@ -19,6 +19,8 @@
 #include <linux/regmap.h>
 #include <linux/reset.h>
 
+#include "sunxi_engine.h"
+
 #define SUN4I_BACKEND_MODCTL_REG		0x800
 #define SUN4I_BACKEND_MODCTL_LINE_SEL			BIT(29)
 #define SUN4I_BACKEND_MODCTL_ITLMOD_EN			BIT(28)
@@ -141,8 +143,7 @@
 #define SUN4I_BACKEND_PIPE_OFF(p)		(0x5000 + (0x400 * (p)))
 
 struct sun4i_backend {
-	struct device_node	*node;
-	struct regmap		*regs;
+	struct sunxi_engine	engine;
 
 	struct reset_control	*reset;
 
@@ -152,17 +153,13 @@ struct sun4i_backend {
 
 	struct clk		*sat_clk;
 	struct reset_control	*sat_reset;
-
-	int			id;
-
-	/* Backend list management */
-	struct list_head	list;
 };
 
-void sun4i_backend_apply_color_correction(struct sun4i_backend *backend);
-void sun4i_backend_disable_color_correction(struct sun4i_backend *backend);
-
-void sun4i_backend_commit(struct sun4i_backend *backend);
+static inline struct sun4i_backend *
+engine_to_sun4i_backend(struct sunxi_engine *engine)
+{
+	return container_of(engine, struct sun4i_backend, engine);
+}
 
 void sun4i_backend_layer_enable(struct sun4i_backend *backend,
 				int layer, bool enable);

drivers/gpu/drm/sun4i/sun4i_crtc.c

@@ -25,10 +25,9 @@
 
 #include <video/videomode.h>
 
-#include "sun4i_backend.h"
 #include "sun4i_crtc.h"
 #include "sun4i_drv.h"
-#include "sun4i_layer.h"
+#include "sunxi_engine.h"
 #include "sun4i_tcon.h"
 
 static void sun4i_crtc_atomic_begin(struct drm_crtc *crtc,
@@ -56,7 +55,7 @@ static void sun4i_crtc_atomic_flush(struct drm_crtc *crtc,
 
 	DRM_DEBUG_DRIVER("Committing plane changes\n");
 
-	sun4i_backend_commit(scrtc->backend);
+	sunxi_engine_commit(scrtc->engine);
 
 	if (event) {
 		crtc->state->event = NULL;
@@ -135,7 +134,7 @@ static const struct drm_crtc_funcs sun4i_crtc_funcs = {
 };
 
 struct sun4i_crtc *sun4i_crtc_init(struct drm_device *drm,
-				   struct sun4i_backend *backend,
+				   struct sunxi_engine *engine,
 				   struct sun4i_tcon *tcon)
 {
 	struct sun4i_crtc *scrtc;
@@ -146,11 +145,11 @@ struct sun4i_crtc *sun4i_crtc_init(struct drm_device *drm,
 	scrtc = devm_kzalloc(drm->dev, sizeof(*scrtc), GFP_KERNEL);
 	if (!scrtc)
 		return ERR_PTR(-ENOMEM);
-	scrtc->backend = backend;
+	scrtc->engine = engine;
 	scrtc->tcon = tcon;
 
 	/* Create our layers */
-	planes = sun4i_layers_init(drm, scrtc);
+	planes = sunxi_engine_layers_init(drm, engine);
 	if (IS_ERR(planes)) {
 		dev_err(drm->dev, "Couldn't create the planes\n");
 		return NULL;

drivers/gpu/drm/sun4i/sun4i_crtc.h

@@ -17,7 +17,7 @@ struct sun4i_crtc {
 	struct drm_crtc			crtc;
 	struct drm_pending_vblank_event	*event;
 
-	struct sun4i_backend		*backend;
+	struct sunxi_engine		*engine;
 	struct sun4i_tcon		*tcon;
 };
 
@@ -27,7 +27,7 @@ static inline struct sun4i_crtc *drm_crtc_to_sun4i_crtc(struct drm_crtc *crtc)
 }
 
 struct sun4i_crtc *sun4i_crtc_init(struct drm_device *drm,
-				   struct sun4i_backend *backend,
+				   struct sunxi_engine *engine,
 				   struct sun4i_tcon *tcon);
 
 #endif /* _SUN4I_CRTC_H_ */

drivers/gpu/drm/sun4i/sun4i_drv.c

@@ -91,7 +91,7 @@ static int sun4i_drv_bind(struct device *dev)
 		goto free_drm;
 	}
 	drm->dev_private = drv;
-	INIT_LIST_HEAD(&drv->backend_list);
+	INIT_LIST_HEAD(&drv->engine_list);
 	INIT_LIST_HEAD(&drv->tcon_list);
 
 	ret = of_reserved_mem_device_init(dev);

drivers/gpu/drm/sun4i/sun4i_drv.h

@@ -18,7 +18,7 @@
 #include <linux/regmap.h>
 
 struct sun4i_drv {
-	struct list_head	backend_list;
+	struct list_head	engine_list;
 	struct list_head	tcon_list;
 
 	struct drm_fbdev_cma	*fbdev;