drm/tegra: Add eDP support

Add support for eDP functionality found on Tegra124 and later SoCs. Only
fast link training is currently supported.

Signed-off-by: Thierry Reding <treding@nvidia.com>
diff --git a/drivers/gpu/drm/tegra/sor.c b/drivers/gpu/drm/tegra/sor.c
new file mode 100644
index 0000000..49ef572
--- /dev/null
+++ b/drivers/gpu/drm/tegra/sor.c
@@ -0,0 +1,1092 @@
+/*
+ * Copyright (C) 2013 NVIDIA Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+#include <linux/tegra-powergate.h>
+
+#include <drm/drm_dp_helper.h>
+
+#include "dc.h"
+#include "drm.h"
+#include "sor.h"
+
+struct tegra_sor {
+	struct host1x_client client;
+	struct tegra_output output;
+	struct device *dev;
+
+	void __iomem *regs;
+
+	struct reset_control *rst;
+	struct clk *clk_parent;
+	struct clk *clk_safe;
+	struct clk *clk_dp;
+	struct clk *clk;
+
+	struct tegra_dpaux *dpaux;
+
+	bool enabled;
+};
+
+static inline struct tegra_sor *
+host1x_client_to_sor(struct host1x_client *client)
+{
+	return container_of(client, struct tegra_sor, client);
+}
+
+static inline struct tegra_sor *to_sor(struct tegra_output *output)
+{
+	return container_of(output, struct tegra_sor, output);
+}
+
+static inline unsigned long tegra_sor_readl(struct tegra_sor *sor,
+					    unsigned long offset)
+{
+	return readl(sor->regs + (offset << 2));
+}
+
+static inline void tegra_sor_writel(struct tegra_sor *sor, unsigned long value,
+				    unsigned long offset)
+{
+	writel(value, sor->regs + (offset << 2));
+}
+
+static int tegra_sor_dp_train_fast(struct tegra_sor *sor,
+				   struct drm_dp_link *link)
+{
+	unsigned long value;
+	unsigned int i;
+	u8 pattern;
+	int err;
+
+	/* setup lane parameters */
+	value = SOR_LANE_DRIVE_CURRENT_LANE3(0x40) |
+		SOR_LANE_DRIVE_CURRENT_LANE2(0x40) |
+		SOR_LANE_DRIVE_CURRENT_LANE1(0x40) |
+		SOR_LANE_DRIVE_CURRENT_LANE0(0x40);
+	tegra_sor_writel(sor, value, SOR_LANE_DRIVE_CURRENT_0);
+
+	value = SOR_LANE_PREEMPHASIS_LANE3(0x0f) |
+		SOR_LANE_PREEMPHASIS_LANE2(0x0f) |
+		SOR_LANE_PREEMPHASIS_LANE1(0x0f) |
+		SOR_LANE_PREEMPHASIS_LANE0(0x0f);
+	tegra_sor_writel(sor, value, SOR_LANE_PREEMPHASIS_0);
+
+	value = SOR_LANE_POST_CURSOR_LANE3(0x00) |
+		SOR_LANE_POST_CURSOR_LANE2(0x00) |
+		SOR_LANE_POST_CURSOR_LANE1(0x00) |
+		SOR_LANE_POST_CURSOR_LANE0(0x00);
+	tegra_sor_writel(sor, value, SOR_LANE_POST_CURSOR_0);
+
+	/* disable LVDS mode */
+	tegra_sor_writel(sor, 0, SOR_LVDS);
+
+	value = tegra_sor_readl(sor, SOR_DP_PADCTL_0);
+	value |= SOR_DP_PADCTL_TX_PU_ENABLE;
+	value &= ~SOR_DP_PADCTL_TX_PU_MASK;
+	value |= SOR_DP_PADCTL_TX_PU(2); /* XXX: don't hardcode? */
+	tegra_sor_writel(sor, value, SOR_DP_PADCTL_0);
+
+	value = tegra_sor_readl(sor, SOR_DP_PADCTL_0);
+	value |= SOR_DP_PADCTL_CM_TXD_3 | SOR_DP_PADCTL_CM_TXD_2 |
+		 SOR_DP_PADCTL_CM_TXD_1 | SOR_DP_PADCTL_CM_TXD_0;
+	tegra_sor_writel(sor, value, SOR_DP_PADCTL_0);
+
+	usleep_range(10, 100);
+
+	value = tegra_sor_readl(sor, SOR_DP_PADCTL_0);
+	value &= ~(SOR_DP_PADCTL_CM_TXD_3 | SOR_DP_PADCTL_CM_TXD_2 |
+		   SOR_DP_PADCTL_CM_TXD_1 | SOR_DP_PADCTL_CM_TXD_0);
+	tegra_sor_writel(sor, value, SOR_DP_PADCTL_0);
+
+	err = tegra_dpaux_prepare(sor->dpaux, DP_SET_ANSI_8B10B);
+	if (err < 0)
+		return err;
+
+	for (i = 0, value = 0; i < link->num_lanes; i++) {
+		unsigned long lane = SOR_DP_TPG_CHANNEL_CODING |
+				     SOR_DP_TPG_SCRAMBLER_NONE |
+				     SOR_DP_TPG_PATTERN_TRAIN1;
+		value = (value << 8) | lane;
+	}
+
+	tegra_sor_writel(sor, value, SOR_DP_TPG);
+
+	pattern = DP_TRAINING_PATTERN_1;
+
+	err = tegra_dpaux_train(sor->dpaux, link, pattern);
+	if (err < 0)
+		return err;
+
+	value = tegra_sor_readl(sor, SOR_DP_SPARE_0);
+	value |= SOR_DP_SPARE_SEQ_ENABLE;
+	value &= ~SOR_DP_SPARE_PANEL_INTERNAL;
+	value |= SOR_DP_SPARE_MACRO_SOR_CLK;
+	tegra_sor_writel(sor, value, SOR_DP_SPARE_0);
+
+	for (i = 0, value = 0; i < link->num_lanes; i++) {
+		unsigned long lane = SOR_DP_TPG_CHANNEL_CODING |
+				     SOR_DP_TPG_SCRAMBLER_NONE |
+				     SOR_DP_TPG_PATTERN_TRAIN2;
+		value = (value << 8) | lane;
+	}
+
+	tegra_sor_writel(sor, value, SOR_DP_TPG);
+
+	pattern = DP_LINK_SCRAMBLING_DISABLE | DP_TRAINING_PATTERN_2;
+
+	err = tegra_dpaux_train(sor->dpaux, link, pattern);
+	if (err < 0)
+		return err;
+
+	for (i = 0, value = 0; i < link->num_lanes; i++) {
+		unsigned long lane = SOR_DP_TPG_CHANNEL_CODING |
+				     SOR_DP_TPG_SCRAMBLER_GALIOS |
+				     SOR_DP_TPG_PATTERN_NONE;
+		value = (value << 8) | lane;
+	}
+
+	tegra_sor_writel(sor, value, SOR_DP_TPG);
+
+	pattern = DP_TRAINING_PATTERN_DISABLE;
+
+	err = tegra_dpaux_train(sor->dpaux, link, pattern);
+	if (err < 0)
+		return err;
+
+	return 0;
+}
+
+static void tegra_sor_super_update(struct tegra_sor *sor)
+{
+	tegra_sor_writel(sor, 0, SOR_SUPER_STATE_0);
+	tegra_sor_writel(sor, 1, SOR_SUPER_STATE_0);
+	tegra_sor_writel(sor, 0, SOR_SUPER_STATE_0);
+}
+
+static void tegra_sor_update(struct tegra_sor *sor)
+{
+	tegra_sor_writel(sor, 0, SOR_STATE_0);
+	tegra_sor_writel(sor, 1, SOR_STATE_0);
+	tegra_sor_writel(sor, 0, SOR_STATE_0);
+}
+
+static int tegra_sor_setup_pwm(struct tegra_sor *sor, unsigned long timeout)
+{
+	unsigned long value;
+
+	value = tegra_sor_readl(sor, SOR_PWM_DIV);
+	value &= ~SOR_PWM_DIV_MASK;
+	value |= 0x400; /* period */
+	tegra_sor_writel(sor, value, SOR_PWM_DIV);
+
+	value = tegra_sor_readl(sor, SOR_PWM_CTL);
+	value &= ~SOR_PWM_CTL_DUTY_CYCLE_MASK;
+	value |= 0x400; /* duty cycle */
+	value &= ~SOR_PWM_CTL_CLK_SEL; /* clock source: PCLK */
+	value |= SOR_PWM_CTL_TRIGGER;
+	tegra_sor_writel(sor, value, SOR_PWM_CTL);
+
+	timeout = jiffies + msecs_to_jiffies(timeout);
+
+	while (time_before(jiffies, timeout)) {
+		value = tegra_sor_readl(sor, SOR_PWM_CTL);
+		if ((value & SOR_PWM_CTL_TRIGGER) == 0)
+			return 0;
+
+		usleep_range(25, 100);
+	}
+
+	return -ETIMEDOUT;
+}
+
+static int tegra_sor_attach(struct tegra_sor *sor)
+{
+	unsigned long value, timeout;
+
+	/* wake up in normal mode */
+	value = tegra_sor_readl(sor, SOR_SUPER_STATE_1);
+	value |= SOR_SUPER_STATE_HEAD_MODE_AWAKE;
+	value |= SOR_SUPER_STATE_MODE_NORMAL;
+	tegra_sor_writel(sor, value, SOR_SUPER_STATE_1);
+	tegra_sor_super_update(sor);
+
+	/* attach */
+	value = tegra_sor_readl(sor, SOR_SUPER_STATE_1);
+	value |= SOR_SUPER_STATE_ATTACHED;
+	tegra_sor_writel(sor, value, SOR_SUPER_STATE_1);
+	tegra_sor_super_update(sor);
+
+	timeout = jiffies + msecs_to_jiffies(250);
+
+	while (time_before(jiffies, timeout)) {
+		value = tegra_sor_readl(sor, SOR_TEST);
+		if ((value & SOR_TEST_ATTACHED) != 0)
+			return 0;
+
+		usleep_range(25, 100);
+	}
+
+	return -ETIMEDOUT;
+}
+
+static int tegra_sor_wakeup(struct tegra_sor *sor)
+{
+	struct tegra_dc *dc = to_tegra_dc(sor->output.encoder.crtc);
+	unsigned long value, timeout;
+
+	/* enable display controller outputs */
+	value = tegra_dc_readl(dc, DC_CMD_DISPLAY_POWER_CONTROL);
+	value |= PW0_ENABLE | PW1_ENABLE | PW2_ENABLE | PW3_ENABLE |
+		 PW4_ENABLE | PM0_ENABLE | PM1_ENABLE;
+	tegra_dc_writel(dc, value, DC_CMD_DISPLAY_POWER_CONTROL);
+
+	tegra_dc_writel(dc, GENERAL_ACT_REQ << 8, DC_CMD_STATE_CONTROL);
+	tegra_dc_writel(dc, GENERAL_ACT_REQ, DC_CMD_STATE_CONTROL);
+
+	timeout = jiffies + msecs_to_jiffies(250);
+
+	/* wait for head to wake up */
+	while (time_before(jiffies, timeout)) {
+		value = tegra_sor_readl(sor, SOR_TEST);
+		value &= SOR_TEST_HEAD_MODE_MASK;
+
+		if (value == SOR_TEST_HEAD_MODE_AWAKE)
+			return 0;
+
+		usleep_range(25, 100);
+	}
+
+	return -ETIMEDOUT;
+}
+
+static int tegra_sor_power_up(struct tegra_sor *sor, unsigned long timeout)
+{
+	unsigned long value;
+
+	value = tegra_sor_readl(sor, SOR_PWR);
+	value |= SOR_PWR_TRIGGER | SOR_PWR_NORMAL_STATE_PU;
+	tegra_sor_writel(sor, value, SOR_PWR);
+
+	timeout = jiffies + msecs_to_jiffies(timeout);
+
+	while (time_before(jiffies, timeout)) {
+		value = tegra_sor_readl(sor, SOR_PWR);
+		if ((value & SOR_PWR_TRIGGER) == 0)
+			return 0;
+
+		usleep_range(25, 100);
+	}
+
+	return -ETIMEDOUT;
+}
+
+static int tegra_output_sor_enable(struct tegra_output *output)
+{
+	struct tegra_dc *dc = to_tegra_dc(output->encoder.crtc);
+	struct drm_display_mode *mode = &dc->base.mode;
+	unsigned int vbe, vse, hbe, hse, vbs, hbs, i;
+	struct tegra_sor *sor = to_sor(output);
+	unsigned long value;
+	int err;
+
+	if (sor->enabled)
+		return 0;
+
+	err = clk_prepare_enable(sor->clk);
+	if (err < 0)
+		return err;
+
+	reset_control_deassert(sor->rst);
+
+	if (sor->dpaux) {
+		err = tegra_dpaux_enable(sor->dpaux);
+		if (err < 0)
+			dev_err(sor->dev, "failed to enable DP: %d\n", err);
+	}
+
+	err = clk_set_parent(sor->clk, sor->clk_safe);
+	if (err < 0)
+		dev_err(sor->dev, "failed to set safe parent clock: %d\n", err);
+
+	value = tegra_sor_readl(sor, SOR_CLK_CNTRL);
+	value &= ~SOR_CLK_CNTRL_DP_CLK_SEL_MASK;
+	value |= SOR_CLK_CNTRL_DP_CLK_SEL_SINGLE_DPCLK;
+	tegra_sor_writel(sor, value, SOR_CLK_CNTRL);
+
+	value = tegra_sor_readl(sor, SOR_PLL_2);
+	value &= ~SOR_PLL_2_BANDGAP_POWERDOWN;
+	tegra_sor_writel(sor, value, SOR_PLL_2);
+	usleep_range(20, 100);
+
+	value = tegra_sor_readl(sor, SOR_PLL_3);
+	value |= SOR_PLL_3_PLL_VDD_MODE_V3_3;
+	tegra_sor_writel(sor, value, SOR_PLL_3);
+
+	value = SOR_PLL_0_ICHPMP(0xf) | SOR_PLL_0_VCOCAP_RST |
+		SOR_PLL_0_PLLREG_LEVEL_V45 | SOR_PLL_0_RESISTOR_EXT;
+	tegra_sor_writel(sor, value, SOR_PLL_0);
+
+	value = tegra_sor_readl(sor, SOR_PLL_2);
+	value |= SOR_PLL_2_SEQ_PLLCAPPD;
+	value &= ~SOR_PLL_2_SEQ_PLLCAPPD_ENFORCE;
+	value |= SOR_PLL_2_LVDS_ENABLE;
+	tegra_sor_writel(sor, value, SOR_PLL_2);
+
+	value = SOR_PLL_1_TERM_COMPOUT | SOR_PLL_1_TMDS_TERM;
+	tegra_sor_writel(sor, value, SOR_PLL_1);
+
+	while (true) {
+		value = tegra_sor_readl(sor, SOR_PLL_2);
+		if ((value & SOR_PLL_2_SEQ_PLLCAPPD_ENFORCE) == 0)
+			break;
+
+		usleep_range(250, 1000);
+	}
+
+	value = tegra_sor_readl(sor, SOR_PLL_2);
+	value &= ~SOR_PLL_2_POWERDOWN_OVERRIDE;
+	value &= ~SOR_PLL_2_PORT_POWERDOWN;
+	tegra_sor_writel(sor, value, SOR_PLL_2);
+
+	/*
+	 * power up
+	 */
+
+	/* set safe link bandwidth (1.62 Gbps) */
+	value = tegra_sor_readl(sor, SOR_CLK_CNTRL);
+	value &= ~SOR_CLK_CNTRL_DP_LINK_SPEED_MASK;
+	value |= SOR_CLK_CNTRL_DP_LINK_SPEED_G1_62;
+	tegra_sor_writel(sor, value, SOR_CLK_CNTRL);
+
+	/* step 1 */
+	value = tegra_sor_readl(sor, SOR_PLL_2);
+	value |= SOR_PLL_2_SEQ_PLLCAPPD_ENFORCE | SOR_PLL_2_PORT_POWERDOWN |
+		 SOR_PLL_2_BANDGAP_POWERDOWN;
+	tegra_sor_writel(sor, value, SOR_PLL_2);
+
+	value = tegra_sor_readl(sor, SOR_PLL_0);
+	value |= SOR_PLL_0_VCOPD | SOR_PLL_0_POWER_OFF;
+	tegra_sor_writel(sor, value, SOR_PLL_0);
+
+	value = tegra_sor_readl(sor, SOR_DP_PADCTL_0);
+	value &= ~SOR_DP_PADCTL_PAD_CAL_PD;
+	tegra_sor_writel(sor, value, SOR_DP_PADCTL_0);
+
+	/* step 2 */
+	err = tegra_io_rail_power_on(TEGRA_IO_RAIL_LVDS);
+	if (err < 0) {
+		dev_err(sor->dev, "failed to power on I/O rail: %d\n", err);
+		return err;
+	}
+
+	usleep_range(5, 100);
+
+	/* step 3 */
+	value = tegra_sor_readl(sor, SOR_PLL_2);
+	value &= ~SOR_PLL_2_BANDGAP_POWERDOWN;
+	tegra_sor_writel(sor, value, SOR_PLL_2);
+
+	usleep_range(20, 100);
+
+	/* step 4 */
+	value = tegra_sor_readl(sor, SOR_PLL_0);
+	value &= ~SOR_PLL_0_POWER_OFF;
+	value &= ~SOR_PLL_0_VCOPD;
+	tegra_sor_writel(sor, value, SOR_PLL_0);
+
+	value = tegra_sor_readl(sor, SOR_PLL_2);
+	value &= ~SOR_PLL_2_SEQ_PLLCAPPD_ENFORCE;
+	tegra_sor_writel(sor, value, SOR_PLL_2);
+
+	usleep_range(200, 1000);
+
+	/* step 5 */
+	value = tegra_sor_readl(sor, SOR_PLL_2);
+	value &= ~SOR_PLL_2_PORT_POWERDOWN;
+	tegra_sor_writel(sor, value, SOR_PLL_2);
+
+	/* switch to DP clock */
+	err = clk_set_parent(sor->clk, sor->clk_dp);
+	if (err < 0)
+		dev_err(sor->dev, "failed to set DP parent clock: %d\n", err);
+
+	/* power dplanes (XXX parameterize based on link?) */
+	value = tegra_sor_readl(sor, SOR_DP_PADCTL_0);
+	value |= SOR_DP_PADCTL_PD_TXD_3 | SOR_DP_PADCTL_PD_TXD_0 |
+		 SOR_DP_PADCTL_PD_TXD_1 | SOR_DP_PADCTL_PD_TXD_2;
+	tegra_sor_writel(sor, value, SOR_DP_PADCTL_0);
+
+	value = tegra_sor_readl(sor, SOR_DP_LINKCTL_0);
+	value &= ~SOR_DP_LINKCTL_LANE_COUNT_MASK;
+	value |= SOR_DP_LINKCTL_LANE_COUNT(4);
+	tegra_sor_writel(sor, value, SOR_DP_LINKCTL_0);
+
+	/* start lane sequencer */
+	value = SOR_LANE_SEQ_CTL_TRIGGER | SOR_LANE_SEQ_CTL_SEQUENCE_DOWN |
+		SOR_LANE_SEQ_CTL_POWER_STATE_UP;
+	tegra_sor_writel(sor, value, SOR_LANE_SEQ_CTL);
+
+	while (true) {
+		value = tegra_sor_readl(sor, SOR_LANE_SEQ_CTL);
+		if ((value & SOR_LANE_SEQ_CTL_TRIGGER) == 0)
+			break;
+
+		usleep_range(250, 1000);
+	}
+
+	/* set link bandwidth (2.7 GHz, XXX: parameterize based on link?) */
+	value = tegra_sor_readl(sor, SOR_CLK_CNTRL);
+	value &= ~SOR_CLK_CNTRL_DP_LINK_SPEED_MASK;
+	value |= SOR_CLK_CNTRL_DP_LINK_SPEED_G2_70;
+	tegra_sor_writel(sor, value, SOR_CLK_CNTRL);
+
+	/* set linkctl */
+	value = tegra_sor_readl(sor, SOR_DP_LINKCTL_0);
+	value |= SOR_DP_LINKCTL_ENABLE;
+
+	value &= ~SOR_DP_LINKCTL_TU_SIZE_MASK;
+	value |= SOR_DP_LINKCTL_TU_SIZE(59); /* XXX: don't hardcode? */
+
+	value |= SOR_DP_LINKCTL_ENHANCED_FRAME;
+	tegra_sor_writel(sor, value, SOR_DP_LINKCTL_0);
+
+	for (i = 0, value = 0; i < 4; i++) {
+		unsigned long lane = SOR_DP_TPG_CHANNEL_CODING |
+				     SOR_DP_TPG_SCRAMBLER_GALIOS |
+				     SOR_DP_TPG_PATTERN_NONE;
+		value = (value << 8) | lane;
+	}
+
+	tegra_sor_writel(sor, value, SOR_DP_TPG);
+
+	value = tegra_sor_readl(sor, SOR_DP_CONFIG_0);
+	value &= ~SOR_DP_CONFIG_WATERMARK_MASK;
+	value |= SOR_DP_CONFIG_WATERMARK(14); /* XXX: don't hardcode? */
+
+	value &= ~SOR_DP_CONFIG_ACTIVE_SYM_COUNT_MASK;
+	value |= SOR_DP_CONFIG_ACTIVE_SYM_COUNT(47); /* XXX: don't hardcode? */
+
+	value &= ~SOR_DP_CONFIG_ACTIVE_SYM_FRAC_MASK;
+	value |= SOR_DP_CONFIG_ACTIVE_SYM_FRAC(9); /* XXX: don't hardcode? */
+
+	value &= ~SOR_DP_CONFIG_ACTIVE_SYM_POLARITY; /* XXX: don't hardcode? */
+
+	value |= SOR_DP_CONFIG_ACTIVE_SYM_ENABLE;
+	value |= SOR_DP_CONFIG_DISPARITY_NEGATIVE; /* XXX: don't hardcode? */
+	tegra_sor_writel(sor, value, SOR_DP_CONFIG_0);
+
+	value = tegra_sor_readl(sor, SOR_DP_AUDIO_HBLANK_SYMBOLS);
+	value &= ~SOR_DP_AUDIO_HBLANK_SYMBOLS_MASK;
+	value |= 137; /* XXX: don't hardcode? */
+	tegra_sor_writel(sor, value, SOR_DP_AUDIO_HBLANK_SYMBOLS);
+
+	value = tegra_sor_readl(sor, SOR_DP_AUDIO_VBLANK_SYMBOLS);
+	value &= ~SOR_DP_AUDIO_VBLANK_SYMBOLS_MASK;
+	value |= 2368; /* XXX: don't hardcode? */
+	tegra_sor_writel(sor, value, SOR_DP_AUDIO_VBLANK_SYMBOLS);
+
+	/* enable pad calibration logic */
+	value = tegra_sor_readl(sor, SOR_DP_PADCTL_0);
+	value |= SOR_DP_PADCTL_PAD_CAL_PD;
+	tegra_sor_writel(sor, value, SOR_DP_PADCTL_0);
+
+	if (sor->dpaux) {
+		/* FIXME: properly convert to struct drm_dp_aux */
+		struct drm_dp_aux *aux = (struct drm_dp_aux *)sor->dpaux;
+		struct drm_dp_link link;
+		u8 rate, lanes;
+
+		err = drm_dp_link_probe(aux, &link);
+		if (err < 0) {
+			dev_err(sor->dev, "failed to probe eDP link: %d\n",
+				err);
+			return err;
+		}
+
+		err = drm_dp_link_power_up(aux, &link);
+		if (err < 0) {
+			dev_err(sor->dev, "failed to power up eDP link: %d\n",
+				err);
+			return err;
+		}
+
+		err = drm_dp_link_configure(aux, &link);
+		if (err < 0) {
+			dev_err(sor->dev, "failed to configure eDP link: %d\n",
+				err);
+			return err;
+		}
+
+		rate = drm_dp_link_rate_to_bw_code(link.rate);
+		lanes = link.num_lanes;
+
+		value = tegra_sor_readl(sor, SOR_CLK_CNTRL);
+		value &= ~SOR_CLK_CNTRL_DP_LINK_SPEED_MASK;
+		value |= SOR_CLK_CNTRL_DP_LINK_SPEED(rate);
+		tegra_sor_writel(sor, value, SOR_CLK_CNTRL);
+
+		value = tegra_sor_readl(sor, SOR_DP_LINKCTL_0);
+		value &= ~SOR_DP_LINKCTL_LANE_COUNT_MASK;
+		value |= SOR_DP_LINKCTL_LANE_COUNT(lanes);
+
+		if (link.capabilities & DP_LINK_CAP_ENHANCED_FRAMING)
+			value |= SOR_DP_LINKCTL_ENHANCED_FRAME;
+
+		tegra_sor_writel(sor, value, SOR_DP_LINKCTL_0);
+
+		/* disable training pattern generator */
+
+		for (i = 0; i < link.num_lanes; i++) {
+			unsigned long lane = SOR_DP_TPG_CHANNEL_CODING |
+					     SOR_DP_TPG_SCRAMBLER_GALIOS |
+					     SOR_DP_TPG_PATTERN_NONE;
+			value = (value << 8) | lane;
+		}
+
+		tegra_sor_writel(sor, value, SOR_DP_TPG);
+
+		err = tegra_sor_dp_train_fast(sor, &link);
+		if (err < 0) {
+			dev_err(sor->dev, "DP fast link training failed: %d\n",
+				err);
+			return err;
+		}
+
+		dev_dbg(sor->dev, "fast link training succeeded\n");
+	}
+
+	err = tegra_sor_power_up(sor, 250);
+	if (err < 0) {
+		dev_err(sor->dev, "failed to power up SOR: %d\n", err);
+		return err;
+	}
+
+	/* start display controller in continuous mode */
+	value = tegra_dc_readl(dc, DC_CMD_STATE_ACCESS);
+	value |= WRITE_MUX;
+	tegra_dc_writel(dc, value, DC_CMD_STATE_ACCESS);
+
+	tegra_dc_writel(dc, VSYNC_H_POSITION(1), DC_DISP_DISP_TIMING_OPTIONS);
+	tegra_dc_writel(dc, DISP_CTRL_MODE_C_DISPLAY, DC_CMD_DISPLAY_COMMAND);
+
+	value = tegra_dc_readl(dc, DC_CMD_STATE_ACCESS);
+	value &= ~WRITE_MUX;
+	tegra_dc_writel(dc, value, DC_CMD_STATE_ACCESS);
+
+	/*
+	 * configure panel (24bpp, vsync-, hsync-, DP-A protocol, complete
+	 * raster, associate with display controller)
+	 */
+	value = SOR_STATE_ASY_PIXELDEPTH_BPP_24_444 |
+		SOR_STATE_ASY_VSYNCPOL |
+		SOR_STATE_ASY_HSYNCPOL |
+		SOR_STATE_ASY_PROTOCOL_DP_A |
+		SOR_STATE_ASY_CRC_MODE_COMPLETE |
+		SOR_STATE_ASY_OWNER(dc->pipe + 1);
+	tegra_sor_writel(sor, value, SOR_STATE_1);
+
+	/*
+	 * TODO: The video timing programming below doesn't seem to match the
+	 * register definitions.
+	 */
+
+	value = ((mode->vtotal & 0x7fff) << 16) | (mode->htotal & 0x7fff);
+	tegra_sor_writel(sor, value, SOR_HEAD_STATE_1(0));
+
+	vse = mode->vsync_end - mode->vsync_start - 1;
+	hse = mode->hsync_end - mode->hsync_start - 1;
+
+	value = ((vse & 0x7fff) << 16) | (hse & 0x7fff);
+	tegra_sor_writel(sor, value, SOR_HEAD_STATE_2(0));
+
+	vbe = vse + (mode->vsync_start - mode->vdisplay);
+	hbe = hse + (mode->hsync_start - mode->hdisplay);
+
+	value = ((vbe & 0x7fff) << 16) | (hbe & 0x7fff);
+	tegra_sor_writel(sor, value, SOR_HEAD_STATE_3(0));
+
+	vbs = vbe + mode->vdisplay;
+	hbs = hbe + mode->hdisplay;
+
+	value = ((vbs & 0x7fff) << 16) | (hbs & 0x7fff);
+	tegra_sor_writel(sor, value, SOR_HEAD_STATE_4(0));
+
+	/* XXX interlaced mode */
+	tegra_sor_writel(sor, 0x00000001, SOR_HEAD_STATE_5(0));
+
+	/* CSTM (LVDS, link A/B, upper) */
+	value = SOR_CSTM_LVDS | SOR_CSTM_LINK_ACT_B | SOR_CSTM_LINK_ACT_B |
+		SOR_CSTM_UPPER;
+	tegra_sor_writel(sor, value, SOR_CSTM);
+
+	/* PWM setup */
+	err = tegra_sor_setup_pwm(sor, 250);
+	if (err < 0) {
+		dev_err(sor->dev, "failed to setup PWM: %d\n", err);
+		return err;
+	}
+
+	value = tegra_dc_readl(dc, DC_DISP_DISP_WIN_OPTIONS);
+	value |= SOR_ENABLE;
+	tegra_dc_writel(dc, value, DC_DISP_DISP_WIN_OPTIONS);
+
+	tegra_sor_update(sor);
+
+	err = tegra_sor_attach(sor);
+	if (err < 0) {
+		dev_err(sor->dev, "failed to attach SOR: %d\n", err);
+		return err;
+	}
+
+	err = tegra_sor_wakeup(sor);
+	if (err < 0) {
+		dev_err(sor->dev, "failed to enable DC: %d\n", err);
+		return err;
+	}
+
+	sor->enabled = true;
+
+	return 0;
+}
+
+static int tegra_sor_detach(struct tegra_sor *sor)
+{
+	unsigned long value, timeout;
+
+	/* switch to safe mode */
+	value = tegra_sor_readl(sor, SOR_SUPER_STATE_1);
+	value &= ~SOR_SUPER_STATE_MODE_NORMAL;
+	tegra_sor_writel(sor, value, SOR_SUPER_STATE_1);
+	tegra_sor_super_update(sor);
+
+	timeout = jiffies + msecs_to_jiffies(250);
+
+	while (time_before(jiffies, timeout)) {
+		value = tegra_sor_readl(sor, SOR_PWR);
+		if (value & SOR_PWR_MODE_SAFE)
+			break;
+	}
+
+	if ((value & SOR_PWR_MODE_SAFE) == 0)
+		return -ETIMEDOUT;
+
+	/* go to sleep */
+	value = tegra_sor_readl(sor, SOR_SUPER_STATE_1);
+	value &= ~SOR_SUPER_STATE_HEAD_MODE_MASK;
+	tegra_sor_writel(sor, value, SOR_SUPER_STATE_1);
+	tegra_sor_super_update(sor);
+
+	/* detach */
+	value = tegra_sor_readl(sor, SOR_SUPER_STATE_1);
+	value &= ~SOR_SUPER_STATE_ATTACHED;
+	tegra_sor_writel(sor, value, SOR_SUPER_STATE_1);
+	tegra_sor_super_update(sor);
+
+	timeout = jiffies + msecs_to_jiffies(250);
+
+	while (time_before(jiffies, timeout)) {
+		value = tegra_sor_readl(sor, SOR_TEST);
+		if ((value & SOR_TEST_ATTACHED) == 0)
+			break;
+
+		usleep_range(25, 100);
+	}
+
+	if ((value & SOR_TEST_ATTACHED) != 0)
+		return -ETIMEDOUT;
+
+	return 0;
+}
+
+static int tegra_sor_power_down(struct tegra_sor *sor)
+{
+	unsigned long value, timeout;
+	int err;
+
+	value = tegra_sor_readl(sor, SOR_PWR);
+	value &= ~SOR_PWR_NORMAL_STATE_PU;
+	value |= SOR_PWR_TRIGGER;
+	tegra_sor_writel(sor, value, SOR_PWR);
+
+	timeout = jiffies + msecs_to_jiffies(250);
+
+	while (time_before(jiffies, timeout)) {
+		value = tegra_sor_readl(sor, SOR_PWR);
+		if ((value & SOR_PWR_TRIGGER) == 0)
+			return 0;
+
+		usleep_range(25, 100);
+	}
+
+	if ((value & SOR_PWR_TRIGGER) != 0)
+		return -ETIMEDOUT;
+
+	err = clk_set_parent(sor->clk, sor->clk_safe);
+	if (err < 0)
+		dev_err(sor->dev, "failed to set safe parent clock: %d\n", err);
+
+	value = tegra_sor_readl(sor, SOR_DP_PADCTL_0);
+	value &= ~(SOR_DP_PADCTL_PD_TXD_3 | SOR_DP_PADCTL_PD_TXD_0 |
+		   SOR_DP_PADCTL_PD_TXD_1 | SOR_DP_PADCTL_PD_TXD_2);
+	tegra_sor_writel(sor, value, SOR_DP_PADCTL_0);
+
+	/* stop lane sequencer */
+	value = SOR_LANE_SEQ_CTL_TRIGGER | SOR_LANE_SEQ_CTL_SEQUENCE_DOWN |
+		SOR_LANE_SEQ_CTL_POWER_STATE_DOWN;
+	tegra_sor_writel(sor, value, SOR_LANE_SEQ_CTL);
+
+	timeout = jiffies + msecs_to_jiffies(250);
+
+	while (time_before(jiffies, timeout)) {
+		value = tegra_sor_readl(sor, SOR_LANE_SEQ_CTL);
+		if ((value & SOR_LANE_SEQ_CTL_TRIGGER) == 0)
+			break;
+
+		usleep_range(25, 100);
+	}
+
+	if ((value & SOR_LANE_SEQ_CTL_TRIGGER) != 0)
+		return -ETIMEDOUT;
+
+	value = tegra_sor_readl(sor, SOR_PLL_2);
+	value |= SOR_PLL_2_PORT_POWERDOWN;
+	tegra_sor_writel(sor, value, SOR_PLL_2);
+
+	usleep_range(20, 100);
+
+	value = tegra_sor_readl(sor, SOR_PLL_0);
+	value |= SOR_PLL_0_POWER_OFF;
+	value |= SOR_PLL_0_VCOPD;
+	tegra_sor_writel(sor, value, SOR_PLL_0);
+
+	value = tegra_sor_readl(sor, SOR_PLL_2);
+	value |= SOR_PLL_2_SEQ_PLLCAPPD;
+	value |= SOR_PLL_2_SEQ_PLLCAPPD_ENFORCE;
+	tegra_sor_writel(sor, value, SOR_PLL_2);
+
+	usleep_range(20, 100);
+
+	return 0;
+}
+
+static int tegra_output_sor_disable(struct tegra_output *output)
+{
+	struct tegra_dc *dc = to_tegra_dc(output->encoder.crtc);
+	struct tegra_sor *sor = to_sor(output);
+	unsigned long value;
+	int err;
+
+	if (!sor->enabled)
+		return 0;
+
+	err = tegra_sor_detach(sor);
+	if (err < 0) {
+		dev_err(sor->dev, "failed to detach SOR: %d\n", err);
+		return err;
+	}
+
+	tegra_sor_writel(sor, 0, SOR_STATE_1);
+	tegra_sor_update(sor);
+
+	/*
+	 * The following accesses registers of the display controller, so make
+	 * sure it's only executed when the output is attached to one.
+	 */
+	if (dc) {
+		/*
+		 * XXX: We can't do this here because it causes the SOR to go
+		 * into an erroneous state and the output will look scrambled
+		 * the next time it is enabled. Presumably this is because we
+		 * should be doing this only on the next VBLANK. A possible
+		 * solution would be to queue a "power-off" event to trigger
+		 * this code to be run during the next VBLANK.
+		 */
+		/*
+		value = tegra_dc_readl(dc, DC_CMD_DISPLAY_POWER_CONTROL);
+		value &= ~(PW0_ENABLE | PW1_ENABLE | PW2_ENABLE | PW3_ENABLE |
+			   PW4_ENABLE | PM0_ENABLE | PM1_ENABLE);
+		tegra_dc_writel(dc, value, DC_CMD_DISPLAY_POWER_CONTROL);
+		*/
+
+		value = tegra_dc_readl(dc, DC_CMD_DISPLAY_COMMAND);
+		value &= ~DISP_CTRL_MODE_MASK;
+		tegra_dc_writel(dc, value, DC_CMD_DISPLAY_COMMAND);
+
+		value = tegra_dc_readl(dc, DC_DISP_DISP_WIN_OPTIONS);
+		value &= ~SOR_ENABLE;
+		tegra_dc_writel(dc, value, DC_DISP_DISP_WIN_OPTIONS);
+
+		tegra_dc_writel(dc, GENERAL_ACT_REQ << 8, DC_CMD_STATE_CONTROL);
+		tegra_dc_writel(dc, GENERAL_ACT_REQ, DC_CMD_STATE_CONTROL);
+	}
+
+	err = tegra_sor_power_down(sor);
+	if (err < 0) {
+		dev_err(sor->dev, "failed to power down SOR: %d\n", err);
+		return err;
+	}
+
+	if (sor->dpaux) {
+		err = tegra_dpaux_disable(sor->dpaux);
+		if (err < 0) {
+			dev_err(sor->dev, "failed to disable DP: %d\n", err);
+			return err;
+		}
+	}
+
+	err = tegra_io_rail_power_off(TEGRA_IO_RAIL_LVDS);
+	if (err < 0) {
+		dev_err(sor->dev, "failed to power off I/O rail: %d\n", err);
+		return err;
+	}
+
+	reset_control_assert(sor->rst);
+	clk_disable_unprepare(sor->clk);
+
+	sor->enabled = false;
+
+	return 0;
+}
+
+static int tegra_output_sor_setup_clock(struct tegra_output *output,
+					struct clk *clk, unsigned long pclk)
+{
+	struct tegra_sor *sor = to_sor(output);
+	int err;
+
+	/* round to next MHz */
+	pclk = DIV_ROUND_UP(pclk / 2, 1000000) * 1000000;
+
+	err = clk_set_parent(clk, sor->clk_parent);
+	if (err < 0) {
+		dev_err(sor->dev, "failed to set parent clock: %d\n", err);
+		return err;
+	}
+
+	err = clk_set_rate(sor->clk_parent, pclk);
+	if (err < 0) {
+		dev_err(sor->dev, "failed to set base clock rate to %lu Hz\n",
+			pclk * 2);
+		return err;
+	}
+
+	return 0;
+}
+
+static int tegra_output_sor_check_mode(struct tegra_output *output,
+				       struct drm_display_mode *mode,
+				       enum drm_mode_status *status)
+{
+	/*
+	 * FIXME: For now, always assume that the mode is okay.
+	 */
+
+	*status = MODE_OK;
+
+	return 0;
+}
+
+static enum drm_connector_status
+tegra_output_sor_detect(struct tegra_output *output)
+{
+	struct tegra_sor *sor = to_sor(output);
+
+	if (sor->dpaux)
+		return tegra_dpaux_detect(sor->dpaux);
+
+	return connector_status_unknown;
+}
+
+static const struct tegra_output_ops sor_ops = {
+	.enable = tegra_output_sor_enable,
+	.disable = tegra_output_sor_disable,
+	.setup_clock = tegra_output_sor_setup_clock,
+	.check_mode = tegra_output_sor_check_mode,
+	.detect = tegra_output_sor_detect,
+};
+
+static int tegra_sor_init(struct host1x_client *client)
+{
+	struct tegra_drm *tegra = dev_get_drvdata(client->parent);
+	struct tegra_sor *sor = host1x_client_to_sor(client);
+	int err;
+
+	if (!sor->dpaux)
+		return -ENODEV;
+
+	sor->output.type = TEGRA_OUTPUT_EDP;
+
+	sor->output.dev = sor->dev;
+	sor->output.ops = &sor_ops;
+
+	err = tegra_output_init(tegra->drm, &sor->output);
+	if (err < 0) {
+		dev_err(sor->dev, "output setup failed: %d\n", err);
+		return err;
+	}
+
+	if (sor->dpaux) {
+		err = tegra_dpaux_attach(sor->dpaux, &sor->output);
+		if (err < 0) {
+			dev_err(sor->dev, "failed to attach DP: %d\n", err);
+			return err;
+		}
+	}
+
+	return 0;
+}
+
+static int tegra_sor_exit(struct host1x_client *client)
+{
+	struct tegra_sor *sor = host1x_client_to_sor(client);
+	int err;
+
+	err = tegra_output_disable(&sor->output);
+	if (err < 0) {
+		dev_err(sor->dev, "output failed to disable: %d\n", err);
+		return err;
+	}
+
+	if (sor->dpaux) {
+		err = tegra_dpaux_detach(sor->dpaux);
+		if (err < 0) {
+			dev_err(sor->dev, "failed to detach DP: %d\n", err);
+			return err;
+		}
+	}
+
+	err = tegra_output_exit(&sor->output);
+	if (err < 0) {
+		dev_err(sor->dev, "output cleanup failed: %d\n", err);
+		return err;
+	}
+
+	return 0;
+}
+
+static const struct host1x_client_ops sor_client_ops = {
+	.init = tegra_sor_init,
+	.exit = tegra_sor_exit,
+};
+
+static int tegra_sor_probe(struct platform_device *pdev)
+{
+	struct device_node *np;
+	struct tegra_sor *sor;
+	struct resource *regs;
+	int err;
+
+	sor = devm_kzalloc(&pdev->dev, sizeof(*sor), GFP_KERNEL);
+	if (!sor)
+		return -ENOMEM;
+
+	sor->output.dev = sor->dev = &pdev->dev;
+
+	np = of_parse_phandle(pdev->dev.of_node, "nvidia,dpaux", 0);
+	if (np) {
+		sor->dpaux = tegra_dpaux_find_by_of_node(np);
+		of_node_put(np);
+
+		if (!sor->dpaux)
+			return -EPROBE_DEFER;
+	}
+
+	err = tegra_output_probe(&sor->output);
+	if (err < 0)
+		return err;
+
+	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	sor->regs = devm_ioremap_resource(&pdev->dev, regs);
+	if (IS_ERR(sor->regs))
+		return PTR_ERR(sor->regs);
+
+	sor->rst = devm_reset_control_get(&pdev->dev, "sor");
+	if (IS_ERR(sor->rst))
+		return PTR_ERR(sor->rst);
+
+	sor->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(sor->clk))
+		return PTR_ERR(sor->clk);
+
+	sor->clk_parent = devm_clk_get(&pdev->dev, "parent");
+	if (IS_ERR(sor->clk_parent))
+		return PTR_ERR(sor->clk_parent);
+
+	err = clk_prepare_enable(sor->clk_parent);
+	if (err < 0)
+		return err;
+
+	sor->clk_safe = devm_clk_get(&pdev->dev, "safe");
+	if (IS_ERR(sor->clk_safe))
+		return PTR_ERR(sor->clk_safe);
+
+	err = clk_prepare_enable(sor->clk_safe);
+	if (err < 0)
+		return err;
+
+	sor->clk_dp = devm_clk_get(&pdev->dev, "dp");
+	if (IS_ERR(sor->clk_dp))
+		return PTR_ERR(sor->clk_dp);
+
+	err = clk_prepare_enable(sor->clk_dp);
+	if (err < 0)
+		return err;
+
+	INIT_LIST_HEAD(&sor->client.list);
+	sor->client.ops = &sor_client_ops;
+	sor->client.dev = &pdev->dev;
+
+	err = host1x_client_register(&sor->client);
+	if (err < 0) {
+		dev_err(&pdev->dev, "failed to register host1x client: %d\n",
+			err);
+		return err;
+	}
+
+	platform_set_drvdata(pdev, sor);
+
+	return 0;
+}
+
+static int tegra_sor_remove(struct platform_device *pdev)
+{
+	struct tegra_sor *sor = platform_get_drvdata(pdev);
+	int err;
+
+	err = host1x_client_unregister(&sor->client);
+	if (err < 0) {
+		dev_err(&pdev->dev, "failed to unregister host1x client: %d\n",
+			err);
+		return err;
+	}
+
+	clk_disable_unprepare(sor->clk_parent);
+	clk_disable_unprepare(sor->clk_safe);
+	clk_disable_unprepare(sor->clk_dp);
+	clk_disable_unprepare(sor->clk);
+
+	return 0;
+}
+
+static const struct of_device_id tegra_sor_of_match[] = {
+	{ .compatible = "nvidia,tegra124-sor", },
+	{ },
+};
+
+struct platform_driver tegra_sor_driver = {
+	.driver = {
+		.name = "tegra-sor",
+		.of_match_table = tegra_sor_of_match,
+	},
+	.probe = tegra_sor_probe,
+	.remove = tegra_sor_remove,
+};