drm/sun4i: Implement A83T HDMI driver

A83T has DW HDMI IP block with a custom PHY similar to Synopsys gen2
HDMI PHY.

Only video output was tested, while HW also supports audio and CEC.
Support for them will be added later.
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180214200906.31509-11-jernej.skrabec@siol.net

drivers/gpu/drm/sun4i/Kconfig

@@ -40,6 +40,15 @@ config DRM_SUN4I_BACKEND
 	  do some alpha blending and feed graphics to TCON. If M is
 	  selected the module will be called sun4i-backend.
 
+config DRM_SUN8I_DW_HDMI
+	tristate "Support for Allwinner version of DesignWare HDMI"
+	depends on DRM_SUN4I
+	select DRM_DW_HDMI
+	help
+	  Choose this option if you have an Allwinner SoC with the
+	  DesignWare HDMI controller with custom HDMI PHY. If M is
+	  selected the module will be called sun8i_dw_hdmi.
+
 config DRM_SUN8I_MIXER
 	tristate "Support for Allwinner Display Engine 2.0 Mixer"
 	default MACH_SUN8I

drivers/gpu/drm/sun4i/Makefile

@@ -10,6 +10,9 @@ sun4i-drm-hdmi-y		+= sun4i_hdmi_enc.o
 sun4i-drm-hdmi-y		+= sun4i_hdmi_i2c.o
 sun4i-drm-hdmi-y		+= sun4i_hdmi_tmds_clk.o
 
+sun8i-drm-hdmi-y		+= sun8i_dw_hdmi.o
+sun8i-drm-hdmi-y		+= sun8i_hdmi_phy.o
+
 sun8i-mixer-y			+= sun8i_mixer.o sun8i_ui_layer.o \
 				   sun8i_vi_layer.o sun8i_ui_scaler.o \
 				   sun8i_vi_scaler.o sun8i_csc.o
@@ -27,4 +30,5 @@ obj-$(CONFIG_DRM_SUN4I)		+= sun6i_drc.o
 
 obj-$(CONFIG_DRM_SUN4I_BACKEND)	+= sun4i-backend.o sun4i-frontend.o
 obj-$(CONFIG_DRM_SUN4I_HDMI)	+= sun4i-drm-hdmi.o
+obj-$(CONFIG_DRM_SUN8I_DW_HDMI)	+= sun8i-drm-hdmi.o
 obj-$(CONFIG_DRM_SUN8I_MIXER)	+= sun8i-mixer.o

drivers/gpu/drm/sun4i/sun8i_dw_hdmi.c

+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2018 Jernej Skrabec <jernej.skrabec@siol.net>
+ */
+
+#include <linux/component.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#include <drm/drm_of.h>
+#include <drm/drmP.h>
+#include <drm/drm_crtc_helper.h>
+
+#include "sun8i_dw_hdmi.h"
+
+static void sun8i_dw_hdmi_encoder_mode_set(struct drm_encoder *encoder,
+					   struct drm_display_mode *mode,
+					   struct drm_display_mode *adj_mode)
+{
+	struct sun8i_dw_hdmi *hdmi = encoder_to_sun8i_dw_hdmi(encoder);
+
+	clk_set_rate(hdmi->clk_tmds, mode->crtc_clock * 1000);
+}
+
+static const struct drm_encoder_helper_funcs
+sun8i_dw_hdmi_encoder_helper_funcs = {
+	.mode_set = sun8i_dw_hdmi_encoder_mode_set,
+};
+
+static const struct drm_encoder_funcs sun8i_dw_hdmi_encoder_funcs = {
+	.destroy = drm_encoder_cleanup,
+};
+
+static enum drm_mode_status
+sun8i_dw_hdmi_mode_valid(struct drm_connector *connector,
+			 const struct drm_display_mode *mode)
+{
+	if (mode->clock > 297000)
+		return MODE_CLOCK_HIGH;
+
+	return MODE_OK;
+}
+
+static int sun8i_dw_hdmi_bind(struct device *dev, struct device *master,
+			      void *data)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct dw_hdmi_plat_data *plat_data;
+	struct drm_device *drm = data;
+	struct device_node *phy_node;
+	struct drm_encoder *encoder;
+	struct sun8i_dw_hdmi *hdmi;
+	int ret;
+
+	if (!pdev->dev.of_node)
+		return -ENODEV;
+
+	hdmi = devm_kzalloc(&pdev->dev, sizeof(*hdmi), GFP_KERNEL);
+	if (!hdmi)
+		return -ENOMEM;
+
+	plat_data = &hdmi->plat_data;
+	hdmi->dev = &pdev->dev;
+	encoder = &hdmi->encoder;
+
+	encoder->possible_crtcs = drm_of_find_possible_crtcs(drm, dev->of_node);
+	/*
+	 * If we failed to find the CRTC(s) which this encoder is
+	 * supposed to be connected to, it's because the CRTC has
+	 * not been registered yet.  Defer probing, and hope that
+	 * the required CRTC is added later.
+	 */
+	if (encoder->possible_crtcs == 0)
+		return -EPROBE_DEFER;
+
+	hdmi->rst_ctrl = devm_reset_control_get(dev, "ctrl");
+	if (IS_ERR(hdmi->rst_ctrl)) {
+		dev_err(dev, "Could not get ctrl reset control\n");
+		return PTR_ERR(hdmi->rst_ctrl);
+	}
+
+	hdmi->clk_tmds = devm_clk_get(dev, "tmds");
+	if (IS_ERR(hdmi->clk_tmds)) {
+		dev_err(dev, "Couldn't get the tmds clock\n");
+		return PTR_ERR(hdmi->clk_tmds);
+	}
+
+	ret = reset_control_deassert(hdmi->rst_ctrl);
+	if (ret) {
+		dev_err(dev, "Could not deassert ctrl reset control\n");
+		return ret;
+	}
+
+	ret = clk_prepare_enable(hdmi->clk_tmds);
+	if (ret) {
+		dev_err(dev, "Could not enable tmds clock\n");
+		goto err_assert_ctrl_reset;
+	}
+
+	phy_node = of_parse_phandle(dev->of_node, "phys", 0);
+	if (!phy_node) {
+		dev_err(dev, "Can't found PHY phandle\n");
+		goto err_disable_clk_tmds;
+	}
+
+	ret = sun8i_hdmi_phy_probe(hdmi, phy_node);
+	of_node_put(phy_node);
+	if (ret) {
+		dev_err(dev, "Couldn't get the HDMI PHY\n");
+		goto err_disable_clk_tmds;
+	}
+
+	drm_encoder_helper_add(encoder, &sun8i_dw_hdmi_encoder_helper_funcs);
+	drm_encoder_init(drm, encoder, &sun8i_dw_hdmi_encoder_funcs,
+			 DRM_MODE_ENCODER_TMDS, NULL);
+
+	sun8i_hdmi_phy_init(hdmi->phy);
+
+	plat_data->mode_valid = &sun8i_dw_hdmi_mode_valid;
+	plat_data->phy_ops = sun8i_hdmi_phy_get_ops();
+	plat_data->phy_name = "sun8i_dw_hdmi_phy";
+	plat_data->phy_data = hdmi->phy;
+
+	platform_set_drvdata(pdev, hdmi);
+
+	hdmi->hdmi = dw_hdmi_bind(pdev, encoder, plat_data);
+
+	/*
+	 * If dw_hdmi_bind() fails we'll never call dw_hdmi_unbind(),
+	 * which would have called the encoder cleanup.  Do it manually.
+	 */
+	if (IS_ERR(hdmi->hdmi)) {
+		ret = PTR_ERR(hdmi->hdmi);
+		goto cleanup_encoder;
+	}
+
+	return 0;
+
+cleanup_encoder:
+	drm_encoder_cleanup(encoder);
+	sun8i_hdmi_phy_remove(hdmi);
+err_disable_clk_tmds:
+	clk_disable_unprepare(hdmi->clk_tmds);
+err_assert_ctrl_reset:
+	reset_control_assert(hdmi->rst_ctrl);
+
+	return ret;
+}
+
+static void sun8i_dw_hdmi_unbind(struct device *dev, struct device *master,
+				 void *data)
+{
+	struct sun8i_dw_hdmi *hdmi = dev_get_drvdata(dev);
+
+	dw_hdmi_unbind(hdmi->hdmi);
+	sun8i_hdmi_phy_remove(hdmi);
+	clk_disable_unprepare(hdmi->clk_tmds);
+	reset_control_assert(hdmi->rst_ctrl);
+}
+
+static const struct component_ops sun8i_dw_hdmi_ops = {
+	.bind	= sun8i_dw_hdmi_bind,
+	.unbind	= sun8i_dw_hdmi_unbind,
+};
+
+static int sun8i_dw_hdmi_probe(struct platform_device *pdev)
+{
+	return component_add(&pdev->dev, &sun8i_dw_hdmi_ops);
+}
+
+static int sun8i_dw_hdmi_remove(struct platform_device *pdev)
+{
+	component_del(&pdev->dev, &sun8i_dw_hdmi_ops);
+
+	return 0;
+}
+
+static const struct of_device_id sun8i_dw_hdmi_dt_ids[] = {
+	{ .compatible = "allwinner,sun8i-a83t-dw-hdmi" },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, sun8i_dw_hdmi_dt_ids);
+
+struct platform_driver sun8i_dw_hdmi_pltfm_driver = {
+	.probe  = sun8i_dw_hdmi_probe,
+	.remove = sun8i_dw_hdmi_remove,
+	.driver = {
+		.name = "sun8i-dw-hdmi",
+		.of_match_table = sun8i_dw_hdmi_dt_ids,
+	},
+};
+module_platform_driver(sun8i_dw_hdmi_pltfm_driver);
+
+MODULE_AUTHOR("Jernej Skrabec <jernej.skrabec@siol.net>");
+MODULE_DESCRIPTION("Allwinner DW HDMI bridge");
+MODULE_LICENSE("GPL");

drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h

+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2018 Jernej Skrabec <jernej.skrabec@siol.net>
+ */
+
+#ifndef _SUN8I_DW_HDMI_H_
+#define _SUN8I_DW_HDMI_H_
+
+#include <drm/bridge/dw_hdmi.h>
+#include <drm/drm_encoder.h>
+#include <linux/clk.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+
+struct sun8i_hdmi_phy {
+	struct clk		*clk_bus;
+	struct clk		*clk_mod;
+	struct regmap		*regs;
+	struct reset_control	*rst_phy;
+};
+
+struct sun8i_dw_hdmi {
+	struct clk			*clk_tmds;
+	struct device			*dev;
+	struct dw_hdmi			*hdmi;
+	struct drm_encoder		encoder;
+	struct sun8i_hdmi_phy		*phy;
+	struct dw_hdmi_plat_data	plat_data;
+	struct reset_control		*rst_ctrl;
+};
+
+static inline struct sun8i_dw_hdmi *
+encoder_to_sun8i_dw_hdmi(struct drm_encoder *encoder)
+{
+	return container_of(encoder, struct sun8i_dw_hdmi, encoder);
+}
+
+int sun8i_hdmi_phy_probe(struct sun8i_dw_hdmi *hdmi, struct device_node *node);
+void sun8i_hdmi_phy_remove(struct sun8i_dw_hdmi *hdmi);
+
+void sun8i_hdmi_phy_init(struct sun8i_hdmi_phy *phy);
+const struct dw_hdmi_phy_ops *sun8i_hdmi_phy_get_ops(void);
+
+#endif /* _SUN8I_DW_HDMI_H_ */

drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c

+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2018 Jernej Skrabec <jernej.skrabec@siol.net>
+ */
+
+#include <linux/of_address.h>
+
+#include "sun8i_dw_hdmi.h"
+
+#define SUN8I_HDMI_PHY_DBG_CTRL_REG	0x0000
+#define SUN8I_HDMI_PHY_DBG_CTRL_PX_LOCK		BIT(0)
+#define SUN8I_HDMI_PHY_DBG_CTRL_POL_MASK	GENMASK(15, 8)
+#define SUN8I_HDMI_PHY_DBG_CTRL_POL(val)	(val << 8)
+#define SUN8I_HDMI_PHY_DBG_CTRL_ADDR_MASK	GENMASK(23, 16)
+#define SUN8I_HDMI_PHY_DBG_CTRL_ADDR(addr)	(addr << 16)
+
+#define SUN8I_HDMI_PHY_REXT_CTRL_REG	0x0004
+#define SUN8I_HDMI_PHY_REXT_CTRL_REXT_EN	BIT(31)
+
+#define SUN8I_HDMI_PHY_READ_EN_REG	0x0010
+#define SUN8I_HDMI_PHY_READ_EN_MAGIC		0x54524545
+
+#define SUN8I_HDMI_PHY_UNSCRAMBLE_REG	0x0014
+#define SUN8I_HDMI_PHY_UNSCRAMBLE_MAGIC		0x42494E47
+
+/*
+ * Address can be actually any value. Here is set to same value as
+ * it is set in BSP driver.
+ */
+#define I2C_ADDR	0x69
+
+static int sun8i_hdmi_phy_config(struct dw_hdmi *hdmi, void *data,
+				 struct drm_display_mode *mode)
+{
+	struct sun8i_hdmi_phy *phy = (struct sun8i_hdmi_phy *)data;
+	u32 val = 0;
+
+	if ((mode->flags & DRM_MODE_FLAG_NHSYNC) &&
+	    (mode->flags & DRM_MODE_FLAG_NHSYNC)) {
+		val = 0x03;
+	}
+
+	regmap_update_bits(phy->regs, SUN8I_HDMI_PHY_DBG_CTRL_REG,
+			   SUN8I_HDMI_PHY_DBG_CTRL_POL_MASK,
+			   SUN8I_HDMI_PHY_DBG_CTRL_POL(val));
+
+	regmap_update_bits(phy->regs, SUN8I_HDMI_PHY_REXT_CTRL_REG,
+			   SUN8I_HDMI_PHY_REXT_CTRL_REXT_EN,
+			   SUN8I_HDMI_PHY_REXT_CTRL_REXT_EN);
+
+	/* power down */
+	dw_hdmi_phy_gen2_txpwron(hdmi, 0);
+	dw_hdmi_phy_gen2_pddq(hdmi, 1);
+
+	dw_hdmi_phy_reset(hdmi);
+
+	dw_hdmi_phy_gen2_pddq(hdmi, 0);
+
+	dw_hdmi_phy_i2c_set_addr(hdmi, I2C_ADDR);
+
+	/*
+	 * Values are taken from BSP HDMI driver. Although AW didn't
+	 * release any documentation, explanation of this values can
+	 * be found in i.MX 6Dual/6Quad Reference Manual.
+	 */
+	if (mode->crtc_clock <= 27000) {
+		dw_hdmi_phy_i2c_write(hdmi, 0x01e0, 0x06);
+		dw_hdmi_phy_i2c_write(hdmi, 0x0000, 0x15);
+		dw_hdmi_phy_i2c_write(hdmi, 0x08da, 0x10);
+		dw_hdmi_phy_i2c_write(hdmi, 0x0007, 0x19);
+		dw_hdmi_phy_i2c_write(hdmi, 0x0318, 0x0e);
+		dw_hdmi_phy_i2c_write(hdmi, 0x8009, 0x09);
+	} else if (mode->crtc_clock <= 74250) {
+		dw_hdmi_phy_i2c_write(hdmi, 0x0540, 0x06);
+		dw_hdmi_phy_i2c_write(hdmi, 0x0005, 0x15);
+		dw_hdmi_phy_i2c_write(hdmi, 0x0000, 0x10);
+		dw_hdmi_phy_i2c_write(hdmi, 0x0007, 0x19);
+		dw_hdmi_phy_i2c_write(hdmi, 0x02b5, 0x0e);
+		dw_hdmi_phy_i2c_write(hdmi, 0x8009, 0x09);
+	} else if (mode->crtc_clock <= 148500) {
+		dw_hdmi_phy_i2c_write(hdmi, 0x04a0, 0x06);
+		dw_hdmi_phy_i2c_write(hdmi, 0x000a, 0x15);
+		dw_hdmi_phy_i2c_write(hdmi, 0x0000, 0x10);
+		dw_hdmi_phy_i2c_write(hdmi, 0x0002, 0x19);
+		dw_hdmi_phy_i2c_write(hdmi, 0x0021, 0x0e);
+		dw_hdmi_phy_i2c_write(hdmi, 0x8029, 0x09);
+	} else {
+		dw_hdmi_phy_i2c_write(hdmi, 0x0000, 0x06);
+		dw_hdmi_phy_i2c_write(hdmi, 0x000f, 0x15);
+		dw_hdmi_phy_i2c_write(hdmi, 0x0000, 0x10);
+		dw_hdmi_phy_i2c_write(hdmi, 0x0002, 0x19);
+		dw_hdmi_phy_i2c_write(hdmi, 0x0000, 0x0e);
+		dw_hdmi_phy_i2c_write(hdmi, 0x802b, 0x09);
+	}
+
+	dw_hdmi_phy_i2c_write(hdmi, 0x0000, 0x1e);
+	dw_hdmi_phy_i2c_write(hdmi, 0x0000, 0x13);
+	dw_hdmi_phy_i2c_write(hdmi, 0x0000, 0x17);
+
+	dw_hdmi_phy_gen2_txpwron(hdmi, 1);
+
+	return 0;
+};
+
+static void sun8i_hdmi_phy_disable(struct dw_hdmi *hdmi, void *data)
+{
+	struct sun8i_hdmi_phy *phy = (struct sun8i_hdmi_phy *)data;
+
+	dw_hdmi_phy_gen2_txpwron(hdmi, 0);
+	dw_hdmi_phy_gen2_pddq(hdmi, 1);
+
+	regmap_update_bits(phy->regs, SUN8I_HDMI_PHY_REXT_CTRL_REG,
+			   SUN8I_HDMI_PHY_REXT_CTRL_REXT_EN, 0);
+}
+
+static const struct dw_hdmi_phy_ops sun8i_hdmi_phy_ops = {
+	.init = &sun8i_hdmi_phy_config,
+	.disable = &sun8i_hdmi_phy_disable,
+	.read_hpd = &dw_hdmi_phy_read_hpd,
+	.update_hpd = &dw_hdmi_phy_update_hpd,
+	.setup_hpd = &dw_hdmi_phy_setup_hpd,
+};
+
+void sun8i_hdmi_phy_init(struct sun8i_hdmi_phy *phy)
+{
+	/* enable read access to HDMI controller */
+	regmap_write(phy->regs, SUN8I_HDMI_PHY_READ_EN_REG,
+		     SUN8I_HDMI_PHY_READ_EN_MAGIC);
+
+	/* unscramble register offsets */
+	regmap_write(phy->regs, SUN8I_HDMI_PHY_UNSCRAMBLE_REG,
+		     SUN8I_HDMI_PHY_UNSCRAMBLE_MAGIC);
+
+	regmap_update_bits(phy->regs, SUN8I_HDMI_PHY_DBG_CTRL_REG,
+			   SUN8I_HDMI_PHY_DBG_CTRL_PX_LOCK,
+			   SUN8I_HDMI_PHY_DBG_CTRL_PX_LOCK);
+
+	/*
+	 * Set PHY I2C address. It must match to the address set by
+	 * dw_hdmi_phy_set_slave_addr().
+	 */
+	regmap_update_bits(phy->regs, SUN8I_HDMI_PHY_DBG_CTRL_REG,
+			   SUN8I_HDMI_PHY_DBG_CTRL_ADDR_MASK,
+			   SUN8I_HDMI_PHY_DBG_CTRL_ADDR(I2C_ADDR));
+}
+
+const struct dw_hdmi_phy_ops *sun8i_hdmi_phy_get_ops(void)
+{
+	return &sun8i_hdmi_phy_ops;
+}
+
+static struct regmap_config sun8i_hdmi_phy_regmap_config = {
+	.reg_bits	= 32,
+	.val_bits	= 32,
+	.reg_stride	= 4,
+	.max_register	= SUN8I_HDMI_PHY_UNSCRAMBLE_REG,
+	.name		= "phy"
+};
+
+static const struct of_device_id sun8i_hdmi_phy_of_table[] = {
+	{ .compatible = "allwinner,sun8i-a83t-hdmi-phy" },
+	{ /* sentinel */ }
+};
+
+int sun8i_hdmi_phy_probe(struct sun8i_dw_hdmi *hdmi, struct device_node *node)
+{
+	struct device *dev = hdmi->dev;
+	struct sun8i_hdmi_phy *phy;
+	struct resource res;
+	void __iomem *regs;
+	int ret;
+
+	if (!of_match_node(sun8i_hdmi_phy_of_table, node)) {
+		dev_err(dev, "Incompatible HDMI PHY\n");
+		return -EINVAL;
+	}
+
+	phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
+	if (!phy)
+		return -ENOMEM;
+
+	ret = of_address_to_resource(node, 0, &res);
+	if (ret) {
+		dev_err(dev, "phy: Couldn't get our resources\n");
+		return ret;
+	}
+
+	regs = devm_ioremap_resource(dev, &res);
+	if (IS_ERR(regs)) {
+		dev_err(dev, "Couldn't map the HDMI PHY registers\n");
+		return PTR_ERR(regs);
+	}
+
+	phy->regs = devm_regmap_init_mmio(dev, regs,
+					  &sun8i_hdmi_phy_regmap_config);
+	if (IS_ERR(phy->regs)) {
+		dev_err(dev, "Couldn't create the HDMI PHY regmap\n");
+		return PTR_ERR(phy->regs);
+	}
+
+	phy->clk_bus = of_clk_get_by_name(node, "bus");
+	if (IS_ERR(phy->clk_bus)) {
+		dev_err(dev, "Could not get bus clock\n");
+		return PTR_ERR(phy->clk_bus);
+	}
+
+	phy->clk_mod = of_clk_get_by_name(node, "mod");
+	if (IS_ERR(phy->clk_mod)) {
+		dev_err(dev, "Could not get mod clock\n");
+		ret = PTR_ERR(phy->clk_mod);
+		goto err_put_clk_bus;
+	}
+
+	phy->rst_phy = of_reset_control_get_shared(node, "phy");
+	if (IS_ERR(phy->rst_phy)) {
+		dev_err(dev, "Could not get phy reset control\n");
+		ret = PTR_ERR(phy->rst_phy);
+		goto err_put_clk_mod;
+	}
+
+	ret = reset_control_deassert(phy->rst_phy);
+	if (ret) {
+		dev_err(dev, "Cannot deassert phy reset control: %d\n", ret);
+		goto err_put_rst_phy;
+	}
+
+	ret = clk_prepare_enable(phy->clk_bus);
+	if (ret) {
+		dev_err(dev, "Cannot enable bus clock: %d\n", ret);
+		goto err_deassert_rst_phy;
+	}
+
+	ret = clk_prepare_enable(phy->clk_mod);
+	if (ret) {
+		dev_err(dev, "Cannot enable mod clock: %d\n", ret);
+		goto err_disable_clk_bus;
+	}
+
+	hdmi->phy = phy;
+
+	return 0;
+
+err_disable_clk_bus:
+	clk_disable_unprepare(phy->clk_bus);
+err_deassert_rst_phy:
+	reset_control_assert(phy->rst_phy);
+err_put_rst_phy:
+	reset_control_put(phy->rst_phy);
+err_put_clk_mod:
+	clk_put(phy->clk_mod);
+err_put_clk_bus:
+	clk_put(phy->clk_bus);
+
+	return ret;
+}
+
+void sun8i_hdmi_phy_remove(struct sun8i_dw_hdmi *hdmi)
+{
+	struct sun8i_hdmi_phy *phy = hdmi->phy;
+
+	clk_disable_unprepare(phy->clk_mod);
+	clk_disable_unprepare(phy->clk_bus);
+
+	reset_control_assert(phy->rst_phy);
+
+	reset_control_put(phy->rst_phy);
+
+	clk_put(phy->clk_mod);
+	clk_put(phy->clk_bus);
+}