drm/sun4i: add support for Allwinner DE2 mixers

Allwinner have a new "Display Engine 2.0" in their new SoCs, which comes
with mixers to do graphic processing and feed data to TCON, like the old
backends and frontends.

Add support for the mixer on Allwinner V3s SoC; it's the simplest one.

Currently a lot of functions are still missing -- more investigations
are needed to gain enough information for them.

Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

1 files changed, 414 insertions, 0 deletions

diff --git a/drivers/gpu/drm/sun4i/sun8i_mixer.c b/drivers/gpu/drm/sun4i/sun8i_mixer.c
new file mode 100644
index 0000000..cb193c5
--- /dev/null
+++ b/drivers/gpu/drm/sun4i/sun8i_mixer.c
@@ -0,0 +1,414 @@
+/*
+ * Copyright (C) 2017 Icenowy Zheng <icenowy@aosc.io>
+ *
+ * Based on sun4i_backend.c, which is:
+ *   Copyright (C) 2015 Free Electrons
+ *   Copyright (C) 2015 NextThing Co
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ */
+
+#include <drm/drmP.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_fb_cma_helper.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_plane_helper.h>
+
+#include <linux/component.h>
+#include <linux/dma-mapping.h>
+#include <linux/reset.h>
+#include <linux/of_device.h>
+
+#include "sun4i_drv.h"
+#include "sun8i_mixer.h"
+#include "sun8i_layer.h"
+#include "sunxi_engine.h"
+
+static void sun8i_mixer_commit(struct sunxi_engine *engine)
+{
+	DRM_DEBUG_DRIVER("Committing changes\n");
+
+	regmap_write(engine->regs, SUN8I_MIXER_GLOBAL_DBUFF,
+		     SUN8I_MIXER_GLOBAL_DBUFF_ENABLE);
+}
+
+void sun8i_mixer_layer_enable(struct sun8i_mixer *mixer,
+				int layer, bool enable)
+{
+	u32 val;
+	/* Currently the first UI channel is used */
+	int chan = mixer->cfg->vi_num;
+
+	DRM_DEBUG_DRIVER("Enabling layer %d in channel %d\n", layer, chan);
+
+	if (enable)
+		val = SUN8I_MIXER_CHAN_UI_LAYER_ATTR_EN;
+	else
+		val = 0;
+
+	regmap_update_bits(mixer->engine.regs,
+			   SUN8I_MIXER_CHAN_UI_LAYER_ATTR(chan, layer),
+			   SUN8I_MIXER_CHAN_UI_LAYER_ATTR_EN, val);
+
+	/* Set the alpha configuration */
+	regmap_update_bits(mixer->engine.regs,
+			   SUN8I_MIXER_CHAN_UI_LAYER_ATTR(chan, layer),
+			   SUN8I_MIXER_CHAN_UI_LAYER_ATTR_ALPHA_MODE_MASK,
+			   SUN8I_MIXER_CHAN_UI_LAYER_ATTR_ALPHA_MODE_DEF);
+	regmap_update_bits(mixer->engine.regs,
+			   SUN8I_MIXER_CHAN_UI_LAYER_ATTR(chan, layer),
+			   SUN8I_MIXER_CHAN_UI_LAYER_ATTR_ALPHA_MASK,
+			   SUN8I_MIXER_CHAN_UI_LAYER_ATTR_ALPHA_DEF);
+}
+
+static int sun8i_mixer_drm_format_to_layer(struct drm_plane *plane,
+					     u32 format, u32 *mode)
+{
+	switch (format) {
+	case DRM_FORMAT_ARGB8888:
+		*mode = SUN8I_MIXER_CHAN_UI_LAYER_ATTR_FBFMT_ARGB8888;
+		break;
+
+	case DRM_FORMAT_XRGB8888:
+		*mode = SUN8I_MIXER_CHAN_UI_LAYER_ATTR_FBFMT_XRGB8888;
+		break;
+
+	case DRM_FORMAT_RGB888:
+		*mode = SUN8I_MIXER_CHAN_UI_LAYER_ATTR_FBFMT_RGB888;
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+int sun8i_mixer_update_layer_coord(struct sun8i_mixer *mixer,
+				     int layer, struct drm_plane *plane)
+{
+	struct drm_plane_state *state = plane->state;
+	struct drm_framebuffer *fb = state->fb;
+	/* Currently the first UI channel is used */
+	int chan = mixer->cfg->vi_num;
+
+	DRM_DEBUG_DRIVER("Updating layer %d\n", layer);
+
+	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(mixer->engine.regs, SUN8I_MIXER_GLOBAL_SIZE,
+			     SUN8I_MIXER_SIZE(state->crtc_w,
+					      state->crtc_h));
+		DRM_DEBUG_DRIVER("Updating blender size\n");
+		regmap_write(mixer->engine.regs,
+			     SUN8I_MIXER_BLEND_ATTR_INSIZE(0),
+			     SUN8I_MIXER_SIZE(state->crtc_w,
+					      state->crtc_h));
+		regmap_write(mixer->engine.regs, SUN8I_MIXER_BLEND_OUTSIZE,
+			     SUN8I_MIXER_SIZE(state->crtc_w,
+					      state->crtc_h));
+		DRM_DEBUG_DRIVER("Updating channel size\n");
+		regmap_write(mixer->engine.regs,
+			     SUN8I_MIXER_CHAN_UI_OVL_SIZE(chan),
+			     SUN8I_MIXER_SIZE(state->crtc_w,
+					      state->crtc_h));
+	}
+
+	/* Set the line width */
+	DRM_DEBUG_DRIVER("Layer line width: %d bytes\n", fb->pitches[0]);
+	regmap_write(mixer->engine.regs,
+		     SUN8I_MIXER_CHAN_UI_LAYER_PITCH(chan, layer),
+		     fb->pitches[0]);
+
+	/* Set height and width */
+	DRM_DEBUG_DRIVER("Layer size W: %u H: %u\n",
+			 state->crtc_w, state->crtc_h);
+	regmap_write(mixer->engine.regs,
+		     SUN8I_MIXER_CHAN_UI_LAYER_SIZE(chan, layer),
+		     SUN8I_MIXER_SIZE(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(mixer->engine.regs,
+		     SUN8I_MIXER_CHAN_UI_LAYER_COORD(chan, layer),
+		     SUN8I_MIXER_COORD(state->crtc_x, state->crtc_y));
+
+	return 0;
+}
+
+int sun8i_mixer_update_layer_formats(struct sun8i_mixer *mixer,
+				       int layer, struct drm_plane *plane)
+{
+	struct drm_plane_state *state = plane->state;
+	struct drm_framebuffer *fb = state->fb;
+	bool interlaced = false;
+	u32 val;
+	/* Currently the first UI channel is used */
+	int chan = mixer->cfg->vi_num;
+	int ret;
+
+	if (plane->state->crtc)
+		interlaced = plane->state->crtc->state->adjusted_mode.flags
+			& DRM_MODE_FLAG_INTERLACE;
+
+	regmap_update_bits(mixer->engine.regs, SUN8I_MIXER_BLEND_OUTCTL,
+			   SUN8I_MIXER_BLEND_OUTCTL_INTERLACED,
+			   interlaced ?
+			   SUN8I_MIXER_BLEND_OUTCTL_INTERLACED : 0);
+
+	DRM_DEBUG_DRIVER("Switching display mixer interlaced mode %s\n",
+			 interlaced ? "on" : "off");
+
+	ret = sun8i_mixer_drm_format_to_layer(plane, fb->format->format,
+						&val);
+	if (ret) {
+		DRM_DEBUG_DRIVER("Invalid format\n");
+		return ret;
+	}
+
+	regmap_update_bits(mixer->engine.regs,
+			   SUN8I_MIXER_CHAN_UI_LAYER_ATTR(chan, layer),
+			   SUN8I_MIXER_CHAN_UI_LAYER_ATTR_FBFMT_MASK, val);
+
+	return 0;
+}
+
+int sun8i_mixer_update_layer_buffer(struct sun8i_mixer *mixer,
+				      int layer, struct drm_plane *plane)
+{
+	struct drm_plane_state *state = plane->state;
+	struct drm_framebuffer *fb = state->fb;
+	struct drm_gem_cma_object *gem;
+	dma_addr_t paddr;
+	/* Currently the first UI channel is used */
+	int chan = mixer->cfg->vi_num;
+	int bpp;
+
+	/* Get the physical address of the buffer in memory */
+	gem = drm_fb_cma_get_gem_obj(fb, 0);
+
+	DRM_DEBUG_DRIVER("Using GEM @ %pad\n", &gem->paddr);
+
+	/* Compute the start of the displayed memory */
+	bpp = fb->format->cpp[0];
+	paddr = gem->paddr + fb->offsets[0];
+
+	/* Fixup framebuffer address for src coordinates */
+	paddr += (state->src_x >> 16) * bpp;
+	paddr += (state->src_y >> 16) * fb->pitches[0];
+
+	/*
+	 * The hardware cannot correctly deal with negative crtc
+	 * coordinates, the display is cropped to the requested size,
+	 * but the display content is not moved.
+	 * Manually move the display content by fixup the framebuffer
+	 * address when crtc_x or crtc_y is negative, like what we
+	 * have did for src_x and src_y.
+	 */
+	if (state->crtc_x < 0)
+		paddr += -state->crtc_x * bpp;
+	if (state->crtc_y < 0)
+		paddr += -state->crtc_y * fb->pitches[0];
+
+	DRM_DEBUG_DRIVER("Setting buffer address to %pad\n", &paddr);
+
+	regmap_write(mixer->engine.regs,
+		     SUN8I_MIXER_CHAN_UI_LAYER_TOP_LADDR(chan, layer),
+		     lower_32_bits(paddr));
+
+	return 0;
+}
+
+static const struct sunxi_engine_ops sun8i_engine_ops = {
+	.commit		= sun8i_mixer_commit,
+	.layers_init	= sun8i_layers_init,
+};
+
+static struct regmap_config sun8i_mixer_regmap_config = {
+	.reg_bits	= 32,
+	.val_bits	= 32,
+	.reg_stride	= 4,
+	.max_register	= 0xbfffc, /* guessed */
+};
+
+static int sun8i_mixer_bind(struct device *dev, struct device *master,
+			      void *data)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct drm_device *drm = data;
+	struct sun4i_drv *drv = drm->dev_private;
+	struct sun8i_mixer *mixer;
+	struct resource *res;
+	void __iomem *regs;
+	int i, ret;
+
+	/*
+	 * The mixer uses single 32-bit register to store memory
+	 * addresses, so that it cannot deal with 64-bit memory
+	 * addresses.
+	 * Restrict the DMA mask so that the mixer won't be
+	 * allocated some memory that is too high.
+	 */
+	ret = dma_set_mask(dev, DMA_BIT_MASK(32));
+	if (ret) {
+		dev_err(dev, "Cannot do 32-bit DMA.\n");
+		return ret;
+	}
+
+	mixer = devm_kzalloc(dev, sizeof(*mixer), GFP_KERNEL);
+	if (!mixer)
+		return -ENOMEM;
+	dev_set_drvdata(dev, mixer);
+	mixer->engine.ops = &sun8i_engine_ops;
+	mixer->engine.node = dev->of_node;
+	/* The ID of the mixer currently doesn't matter */
+	mixer->engine.id = -1;
+
+	mixer->cfg = of_device_get_match_data(dev);
+	if (!mixer->cfg)
+		return -EINVAL;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	regs = devm_ioremap_resource(dev, res);
+	if (IS_ERR(regs))
+		return PTR_ERR(regs);
+
+	mixer->engine.regs = devm_regmap_init_mmio(dev, regs,
+						   &sun8i_mixer_regmap_config);
+	if (IS_ERR(mixer->engine.regs)) {
+		dev_err(dev, "Couldn't create the mixer regmap\n");
+		return PTR_ERR(mixer->engine.regs);
+	}
+
+	mixer->reset = devm_reset_control_get(dev, NULL);
+	if (IS_ERR(mixer->reset)) {
+		dev_err(dev, "Couldn't get our reset line\n");
+		return PTR_ERR(mixer->reset);
+	}
+
+	ret = reset_control_deassert(mixer->reset);
+	if (ret) {
+		dev_err(dev, "Couldn't deassert our reset line\n");
+		return ret;
+	}
+
+	mixer->bus_clk = devm_clk_get(dev, "bus");
+	if (IS_ERR(mixer->bus_clk)) {
+		dev_err(dev, "Couldn't get the mixer bus clock\n");
+		ret = PTR_ERR(mixer->bus_clk);
+		goto err_assert_reset;
+	}
+	clk_prepare_enable(mixer->bus_clk);
+
+	mixer->mod_clk = devm_clk_get(dev, "mod");
+	if (IS_ERR(mixer->mod_clk)) {
+		dev_err(dev, "Couldn't get the mixer module clock\n");
+		ret = PTR_ERR(mixer->mod_clk);
+		goto err_disable_bus_clk;
+	}
+	clk_prepare_enable(mixer->mod_clk);
+
+	list_add_tail(&mixer->engine.list, &drv->engine_list);
+
+	/* Reset the registers */
+	for (i = 0x0; i < 0x20000; i += 4)
+		regmap_write(mixer->engine.regs, i, 0);
+
+	/* Enable the mixer */
+	regmap_write(mixer->engine.regs, SUN8I_MIXER_GLOBAL_CTL,
+		     SUN8I_MIXER_GLOBAL_CTL_RT_EN);
+
+	/* Initialize blender */
+	regmap_write(mixer->engine.regs, SUN8I_MIXER_BLEND_FCOLOR_CTL,
+		     SUN8I_MIXER_BLEND_FCOLOR_CTL_DEF);
+	regmap_write(mixer->engine.regs, SUN8I_MIXER_BLEND_PREMULTIPLY,
+		     SUN8I_MIXER_BLEND_PREMULTIPLY_DEF);
+	regmap_write(mixer->engine.regs, SUN8I_MIXER_BLEND_BKCOLOR,
+		     SUN8I_MIXER_BLEND_BKCOLOR_DEF);
+	regmap_write(mixer->engine.regs, SUN8I_MIXER_BLEND_MODE(0),
+		     SUN8I_MIXER_BLEND_MODE_DEF);
+	regmap_write(mixer->engine.regs, SUN8I_MIXER_BLEND_CK_CTL,
+		     SUN8I_MIXER_BLEND_CK_CTL_DEF);
+
+	regmap_write(mixer->engine.regs,
+		     SUN8I_MIXER_BLEND_ATTR_FCOLOR(0),
+		     SUN8I_MIXER_BLEND_ATTR_FCOLOR_DEF);
+
+	/* Select the first UI channel */
+	DRM_DEBUG_DRIVER("Selecting channel %d (first UI channel)\n",
+			 mixer->cfg->vi_num);
+	regmap_write(mixer->engine.regs, SUN8I_MIXER_BLEND_ROUTE,
+		     mixer->cfg->vi_num);
+
+	return 0;
+
+err_disable_bus_clk:
+	clk_disable_unprepare(mixer->bus_clk);
+err_assert_reset:
+	reset_control_assert(mixer->reset);
+	return ret;
+}
+
+static void sun8i_mixer_unbind(struct device *dev, struct device *master,
+				 void *data)
+{
+	struct sun8i_mixer *mixer = dev_get_drvdata(dev);
+
+	list_del(&mixer->engine.list);
+
+	clk_disable_unprepare(mixer->mod_clk);
+	clk_disable_unprepare(mixer->bus_clk);
+	reset_control_assert(mixer->reset);
+}
+
+static const struct component_ops sun8i_mixer_ops = {
+	.bind	= sun8i_mixer_bind,
+	.unbind	= sun8i_mixer_unbind,
+};
+
+static int sun8i_mixer_probe(struct platform_device *pdev)
+{
+	return component_add(&pdev->dev, &sun8i_mixer_ops);
+}
+
+static int sun8i_mixer_remove(struct platform_device *pdev)
+{
+	component_del(&pdev->dev, &sun8i_mixer_ops);
+
+	return 0;
+}
+
+static const struct sun8i_mixer_cfg sun8i_v3s_mixer_cfg = {
+	.vi_num = 2,
+	.ui_num = 1,
+};
+
+static const struct of_device_id sun8i_mixer_of_table[] = {
+	{
+		.compatible = "allwinner,sun8i-v3s-de2-mixer",
+		.data = &sun8i_v3s_mixer_cfg,
+	},
+	{ }
+};
+MODULE_DEVICE_TABLE(of, sun8i_mixer_of_table);
+
+static struct platform_driver sun8i_mixer_platform_driver = {
+	.probe		= sun8i_mixer_probe,
+	.remove		= sun8i_mixer_remove,
+	.driver		= {
+		.name		= "sun8i-mixer",
+		.of_match_table	= sun8i_mixer_of_table,
+	},
+};
+module_platform_driver(sun8i_mixer_platform_driver);
+
+MODULE_AUTHOR("Icenowy Zheng <icenowy@aosc.io>");
+MODULE_DESCRIPTION("Allwinner DE2 Mixer driver");
+MODULE_LICENSE("GPL");