drm: sti: add HDMI driver

Add driver for HDMI output.
HDMI PHY registers are mixed into HDMI device registers
and their is only one IRQ for all this hardware block.
That is why PHYs aren't using phy framework but only a
thin hdmi_phy_ops structure with start and stop functions.

HDMI driver is mapped on drm_bridge and drm_connector structures.
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Reviewed-by: Rob Clark <robdclark@gmail.com>

drivers/gpu/drm/sti/Makefile

+stihdmi-y := sti_hdmi.o \
+	sti_hdmi_tx3g0c55phy.o \
+	sti_hdmi_tx3g4c28phy.o \
+
 obj-$(CONFIG_DRM_STI) = \
 	sti_vtg.o \
-	sti_vtac.o
\ No newline at end of file
+	sti_vtac.o \
+	stihdmi.o
\ No newline at end of file

drivers/gpu/drm/sti/sti_hdmi.h

+/*
+ * Copyright (C) STMicroelectronics SA 2014
+ * Author: Vincent Abriou <vincent.abriou@st.com> for STMicroelectronics.
+ * License terms:  GNU General Public License (GPL), version 2
+ */
+
+#ifndef _STI_HDMI_H_
+#define _STI_HDMI_H_
+
+#include <linux/platform_device.h>
+
+#include <drm/drmP.h>
+
+#define HDMI_STA           0x0010
+#define HDMI_STA_DLL_LCK   BIT(5)
+
+struct sti_hdmi;
+
+struct hdmi_phy_ops {
+	bool (*start)(struct sti_hdmi *hdmi);
+	void (*stop)(struct sti_hdmi *hdmi);
+};
+
+/**
+ * STI hdmi structure
+ *
+ * @dev: driver device
+ * @drm_dev: pointer to drm device
+ * @mode: current display mode selected
+ * @regs: hdmi register
+ * @syscfg: syscfg register for pll rejection configuration
+ * @clk_pix: hdmi pixel clock
+ * @clk_tmds: hdmi tmds clock
+ * @clk_phy: hdmi phy clock
+ * @clk_audio: hdmi audio clock
+ * @irq: hdmi interrupt number
+ * @irq_status: interrupt status register
+ * @phy_ops: phy start/stop operations
+ * @enabled: true if hdmi is enabled else false
+ * @hpd_gpio: hdmi hot plug detect gpio number
+ * @hpd: hot plug detect status
+ * @wait_event: wait event
+ * @event_received: wait event status
+ * @reset: reset control of the hdmi phy
+ */
+struct sti_hdmi {
+	struct device dev;
+	struct drm_device *drm_dev;
+	struct drm_display_mode mode;
+	void __iomem *regs;
+	void __iomem *syscfg;
+	struct clk *clk_pix;
+	struct clk *clk_tmds;
+	struct clk *clk_phy;
+	struct clk *clk_audio;
+	int irq;
+	u32 irq_status;
+	struct hdmi_phy_ops *phy_ops;
+	bool enabled;
+	int hpd_gpio;
+	bool hpd;
+	wait_queue_head_t wait_event;
+	bool event_received;
+	struct reset_control *reset;
+};
+
+u32 hdmi_read(struct sti_hdmi *hdmi, int offset);
+void hdmi_write(struct sti_hdmi *hdmi, u32 val, int offset);
+
+/**
+ * hdmi phy config structure
+ *
+ * A pointer to an array of these structures is passed to a TMDS (HDMI) output
+ * via the control interface to provide board and SoC specific
+ * configurations of the HDMI PHY. Each entry in the array specifies a hardware
+ * specific configuration for a given TMDS clock frequency range.
+ *
+ * @min_tmds_freq: Lower bound of TMDS clock frequency this entry applies to
+ * @max_tmds_freq: Upper bound of TMDS clock frequency this entry applies to
+ * @config: SoC specific register configuration
+ */
+struct hdmi_phy_config {
+	u32 min_tmds_freq;
+	u32 max_tmds_freq;
+	u32 config[4];
+};
+
+#endif

drivers/gpu/drm/sti/sti_hdmi_tx3g0c55phy.h

+/*
+ * Copyright (C) STMicroelectronics SA 2014
+ * Author: Benjamin Gaignard <benjamin.gaignard@st.com> for STMicroelectronics.
+ * License terms:  GNU General Public License (GPL), version 2
+ */
+
+#ifndef _STI_HDMI_TX3G0C55PHY_H_
+#define _STI_HDMI_TX3G0C55PHY_H_
+
+#include "sti_hdmi.h"
+
+extern struct hdmi_phy_ops tx3g0c55phy_ops;
+
+#endif

drivers/gpu/drm/sti/sti_hdmi_tx3g4c28phy.c

+/*
+ * Copyright (C) STMicroelectronics SA 2014
+ * Author: Vincent Abriou <vincent.abriou@st.com> for STMicroelectronics.
+ * License terms:  GNU General Public License (GPL), version 2
+ */
+
+#include "sti_hdmi_tx3g4c28phy.h"
+
+#define HDMI_SRZ_CFG                             0x504
+#define HDMI_SRZ_PLL_CFG                         0x510
+#define HDMI_SRZ_ICNTL                           0x518
+#define HDMI_SRZ_CALCODE_EXT                     0x520
+
+#define HDMI_SRZ_CFG_EN                          BIT(0)
+#define HDMI_SRZ_CFG_DISABLE_BYPASS_SINK_CURRENT BIT(1)
+#define HDMI_SRZ_CFG_EXTERNAL_DATA               BIT(16)
+#define HDMI_SRZ_CFG_RBIAS_EXT                   BIT(17)
+#define HDMI_SRZ_CFG_EN_SINK_TERM_DETECTION      BIT(18)
+#define HDMI_SRZ_CFG_EN_BIASRES_DETECTION        BIT(19)
+#define HDMI_SRZ_CFG_EN_SRC_TERMINATION          BIT(24)
+
+#define HDMI_SRZ_CFG_INTERNAL_MASK  (HDMI_SRZ_CFG_EN     | \
+		HDMI_SRZ_CFG_DISABLE_BYPASS_SINK_CURRENT | \
+		HDMI_SRZ_CFG_EXTERNAL_DATA               | \
+		HDMI_SRZ_CFG_RBIAS_EXT                   | \
+		HDMI_SRZ_CFG_EN_SINK_TERM_DETECTION      | \
+		HDMI_SRZ_CFG_EN_BIASRES_DETECTION        | \
+		HDMI_SRZ_CFG_EN_SRC_TERMINATION)
+
+#define PLL_CFG_EN                               BIT(0)
+#define PLL_CFG_NDIV_SHIFT                       (8)
+#define PLL_CFG_IDF_SHIFT                        (16)
+#define PLL_CFG_ODF_SHIFT                        (24)
+
+#define ODF_DIV_1                                (0)
+#define ODF_DIV_2                                (1)
+#define ODF_DIV_4                                (2)
+#define ODF_DIV_8                                (3)
+
+#define HDMI_TIMEOUT_PLL_LOCK  50  /*milliseconds */
+
+struct plldividers_s {
+	uint32_t min;
+	uint32_t max;
+	uint32_t idf;
+	uint32_t odf;
+};
+
+/*
+ * Functional specification recommended values
+ */
+#define NB_PLL_MODE 5
+static struct plldividers_s plldividers[NB_PLL_MODE] = {
+	{0, 20000000, 1, ODF_DIV_8},
+	{20000000, 42500000, 2, ODF_DIV_8},
+	{42500000, 85000000, 4, ODF_DIV_4},
+	{85000000, 170000000, 8, ODF_DIV_2},
+	{170000000, 340000000, 16, ODF_DIV_1}
+};
+
+#define NB_HDMI_PHY_CONFIG 2
+static struct hdmi_phy_config hdmiphy_config[NB_HDMI_PHY_CONFIG] = {
+	{0, 250000000, {0x0, 0x0, 0x0, 0x0} },
+	{250000000, 300000000, {0x1110, 0x0, 0x0, 0x0} },
+};
+
+/**
+ * Start hdmi phy macro cell tx3g4c28
+ *
+ * @hdmi: pointer on the hdmi internal structure
+ *
+ * Return false if an error occur
+ */
+static bool sti_hdmi_tx3g4c28phy_start(struct sti_hdmi *hdmi)
+{
+	u32 ckpxpll = hdmi->mode.clock * 1000;
+	u32 val, tmdsck, idf, odf, pllctrl = 0;
+	bool foundplldivides = false;
+	int i;
+
+	DRM_DEBUG_DRIVER("ckpxpll = %dHz\n", ckpxpll);
+
+	for (i = 0; i < NB_PLL_MODE; i++) {
+		if (ckpxpll >= plldividers[i].min &&
+		    ckpxpll < plldividers[i].max) {
+			idf = plldividers[i].idf;
+			odf = plldividers[i].odf;
+			foundplldivides = true;
+			break;
+		}
+	}
+
+	if (!foundplldivides) {
+		DRM_ERROR("input TMDS clock speed (%d) not supported\n",
+			  ckpxpll);
+		goto err;
+	}
+
+	/* Assuming no pixel repetition and 24bits color */
+	tmdsck = ckpxpll;
+	pllctrl |= 40 << PLL_CFG_NDIV_SHIFT;
+
+	if (tmdsck > 340000000) {
+		DRM_ERROR("output TMDS clock (%d) out of range\n", tmdsck);
+		goto err;
+	}
+
+	pllctrl |= idf << PLL_CFG_IDF_SHIFT;
+	pllctrl |= odf << PLL_CFG_ODF_SHIFT;
+
+	/*
+	 * Configure and power up the PHY PLL
+	 */
+	hdmi->event_received = false;
+	DRM_DEBUG_DRIVER("pllctrl = 0x%x\n", pllctrl);
+	hdmi_write(hdmi, (pllctrl | PLL_CFG_EN), HDMI_SRZ_PLL_CFG);
+
+	/* wait PLL interrupt */
+	wait_event_interruptible_timeout(hdmi->wait_event,
+					 hdmi->event_received == true,
+					 msecs_to_jiffies
+					 (HDMI_TIMEOUT_PLL_LOCK));
+
+	if ((hdmi_read(hdmi, HDMI_STA) & HDMI_STA_DLL_LCK) == 0) {
+		DRM_ERROR("hdmi phy pll not locked\n");
+		goto err;
+	}
+
+	DRM_DEBUG_DRIVER("got PHY PLL Lock\n");
+
+	val = (HDMI_SRZ_CFG_EN |
+	       HDMI_SRZ_CFG_EXTERNAL_DATA |
+	       HDMI_SRZ_CFG_EN_BIASRES_DETECTION |
+	       HDMI_SRZ_CFG_EN_SINK_TERM_DETECTION);
+
+	if (tmdsck > 165000000)
+		val |= HDMI_SRZ_CFG_EN_SRC_TERMINATION;
+
+	/*
+	 * To configure the source termination and pre-emphasis appropriately
+	 * for different high speed TMDS clock frequencies a phy configuration
+	 * table must be provided, tailored to the SoC and board combination.
+	 */
+	for (i = 0; i < NB_HDMI_PHY_CONFIG; i++) {
+		if ((hdmiphy_config[i].min_tmds_freq <= tmdsck) &&
+		    (hdmiphy_config[i].max_tmds_freq >= tmdsck)) {
+			val |= (hdmiphy_config[i].config[0]
+				& ~HDMI_SRZ_CFG_INTERNAL_MASK);
+			hdmi_write(hdmi, val, HDMI_SRZ_CFG);
+
+			val = hdmiphy_config[i].config[1];
+			hdmi_write(hdmi, val, HDMI_SRZ_ICNTL);
+
+			val = hdmiphy_config[i].config[2];
+			hdmi_write(hdmi, val, HDMI_SRZ_CALCODE_EXT);
+
+			DRM_DEBUG_DRIVER("serializer cfg 0x%x 0x%x 0x%x\n",
+					 hdmiphy_config[i].config[0],
+					 hdmiphy_config[i].config[1],
+					 hdmiphy_config[i].config[2]);
+			return true;
+		}
+	}
+
+	/*
+	 * Default, power up the serializer with no pre-emphasis or
+	 * output swing correction
+	 */
+	hdmi_write(hdmi, val,  HDMI_SRZ_CFG);
+	hdmi_write(hdmi, 0x0, HDMI_SRZ_ICNTL);
+	hdmi_write(hdmi, 0x0, HDMI_SRZ_CALCODE_EXT);
+
+	return true;
+
+err:
+	return false;
+}
+
+/**
+ * Stop hdmi phy macro cell tx3g4c28
+ *
+ * @hdmi: pointer on the hdmi internal structure
+ */
+static void sti_hdmi_tx3g4c28phy_stop(struct sti_hdmi *hdmi)
+{
+	int val = 0;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	hdmi->event_received = false;
+
+	val = HDMI_SRZ_CFG_EN_SINK_TERM_DETECTION;
+	val |= HDMI_SRZ_CFG_EN_BIASRES_DETECTION;
+
+	hdmi_write(hdmi, val, HDMI_SRZ_CFG);
+	hdmi_write(hdmi, 0, HDMI_SRZ_PLL_CFG);
+
+	/* wait PLL interrupt */
+	wait_event_interruptible_timeout(hdmi->wait_event,
+					 hdmi->event_received == true,
+					 msecs_to_jiffies
+					 (HDMI_TIMEOUT_PLL_LOCK));
+
+	if (hdmi_read(hdmi, HDMI_STA) & HDMI_STA_DLL_LCK)
+		DRM_ERROR("hdmi phy pll not well disabled\n");
+}
+
+struct hdmi_phy_ops tx3g4c28phy_ops = {
+	.start = sti_hdmi_tx3g4c28phy_start,
+	.stop = sti_hdmi_tx3g4c28phy_stop,
+};

drivers/gpu/drm/sti/sti_hdmi_tx3g4c28phy.h

+/*
+ * Copyright (C) STMicroelectronics SA 2014
+ * Author: Benjamin Gaignard <benjamin.gaignard@st.com> for STMicroelectronics.
+ * License terms:  GNU General Public License (GPL), version 2
+ */
+
+#ifndef _STI_HDMI_TX3G4C28PHY_H_
+#define _STI_HDMI_TX3G4C28PHY_H_
+
+#include "sti_hdmi.h"
+
+extern struct hdmi_phy_ops tx3g4c28phy_ops;
+
+#endif