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

1 files changed, 270 insertions, 0 deletions

diff --git a/drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c b/drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c
new file mode 100644
index 0000000..e5bfcdd
--- /dev/null
+++ b/drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c
@@ -0,0 +1,270 @@
+// 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);
+}