drm/sun4i: Add HDMI support

The earlier Allwinner SoCs (A10, A10s, A20, A31) have an embedded HDMI
controller.

That HDMI controller is able to do audio and CEC, but those have been left
out for now.
Reviewed-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>

drivers/gpu/drm/sun4i/Kconfig

@@ -13,6 +13,14 @@ config DRM_SUN4I
 	  Display Engine. If M is selected the module will be called
 	  sun4i-drm.
 
+config DRM_SUN4I_HDMI
+       tristate "Allwinner A10 HDMI Controller Support"
+       depends on DRM_SUN4I
+       default DRM_SUN4I
+       help
+	  Choose this option if you have an Allwinner SoC with an HDMI
+	  controller.
+
 config DRM_SUN4I_BACKEND
 	tristate "Support for Allwinner A10 Display Engine Backend"
 	depends on DRM_SUN4I

drivers/gpu/drm/sun4i/Makefile

 sun4i-drm-y += sun4i_drv.o
 sun4i-drm-y += sun4i_framebuffer.o
 
+sun4i-drm-hdmi-y += sun4i_hdmi_enc.o
+sun4i-drm-hdmi-y += sun4i_hdmi_ddc_clk.o
+sun4i-drm-hdmi-y += sun4i_hdmi_tmds_clk.o
+
 sun4i-tcon-y += sun4i_tcon.o
 sun4i-tcon-y += sun4i_rgb.o
 sun4i-tcon-y += sun4i_dotclock.o
@@ -15,4 +19,5 @@ obj-$(CONFIG_DRM_SUN4I)		+= sun6i_drc.o
 obj-$(CONFIG_DRM_SUN4I)		+= sun4i_tv.o
 
 obj-$(CONFIG_DRM_SUN4I_BACKEND)		+= sun4i-backend.o
+obj-$(CONFIG_DRM_SUN4I_HDMI)	+= sun4i-drm-hdmi.o
 obj-$(CONFIG_DRM_SUN8I_MIXER)		+= sun8i-mixer.o

drivers/gpu/drm/sun4i/sun4i_hdmi.h

+/*
+ * Copyright (C) 2016 Maxime Ripard
+ *
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * 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.
+ */
+
+#ifndef _SUN4I_HDMI_H_
+#define _SUN4I_HDMI_H_
+
+#include <drm/drm_connector.h>
+#include <drm/drm_encoder.h>
+
+#define SUN4I_HDMI_CTRL_REG		0x004
+#define SUN4I_HDMI_CTRL_ENABLE			BIT(31)
+
+#define SUN4I_HDMI_IRQ_REG		0x008
+#define SUN4I_HDMI_IRQ_STA_MASK			0x73
+#define SUN4I_HDMI_IRQ_STA_FIFO_OF		BIT(1)
+#define SUN4I_HDMI_IRQ_STA_FIFO_UF		BIT(0)
+
+#define SUN4I_HDMI_HPD_REG		0x00c
+#define SUN4I_HDMI_HPD_HIGH			BIT(0)
+
+#define SUN4I_HDMI_VID_CTRL_REG		0x010
+#define SUN4I_HDMI_VID_CTRL_ENABLE		BIT(31)
+#define SUN4I_HDMI_VID_CTRL_HDMI_MODE		BIT(30)
+
+#define SUN4I_HDMI_VID_TIMING_ACT_REG	0x014
+#define SUN4I_HDMI_VID_TIMING_BP_REG	0x018
+#define SUN4I_HDMI_VID_TIMING_FP_REG	0x01c
+#define SUN4I_HDMI_VID_TIMING_SPW_REG	0x020
+
+#define SUN4I_HDMI_VID_TIMING_X(x)		((((x) - 1) & GENMASK(11, 0)))
+#define SUN4I_HDMI_VID_TIMING_Y(y)		((((y) - 1) & GENMASK(11, 0)) << 16)
+
+#define SUN4I_HDMI_VID_TIMING_POL_REG	0x024
+#define SUN4I_HDMI_VID_TIMING_POL_TX_CLK        (0x3e0 << 16)
+#define SUN4I_HDMI_VID_TIMING_POL_VSYNC		BIT(1)
+#define SUN4I_HDMI_VID_TIMING_POL_HSYNC		BIT(0)
+
+#define SUN4I_HDMI_AVI_INFOFRAME_REG(n)	(0x080 + (n))
+
+#define SUN4I_HDMI_PAD_CTRL0_REG	0x200
+#define SUN4I_HDMI_PAD_CTRL0_BIASEN		BIT(31)
+#define SUN4I_HDMI_PAD_CTRL0_LDOCEN		BIT(30)
+#define SUN4I_HDMI_PAD_CTRL0_LDODEN		BIT(29)
+#define SUN4I_HDMI_PAD_CTRL0_PWENC		BIT(28)
+#define SUN4I_HDMI_PAD_CTRL0_PWEND		BIT(27)
+#define SUN4I_HDMI_PAD_CTRL0_PWENG		BIT(26)
+#define SUN4I_HDMI_PAD_CTRL0_CKEN		BIT(25)
+#define SUN4I_HDMI_PAD_CTRL0_TXEN		BIT(23)
+
+#define SUN4I_HDMI_PAD_CTRL1_REG	0x204
+#define SUN4I_HDMI_PAD_CTRL1_AMP_OPT		BIT(23)
+#define SUN4I_HDMI_PAD_CTRL1_AMPCK_OPT		BIT(22)
+#define SUN4I_HDMI_PAD_CTRL1_EMP_OPT		BIT(20)
+#define SUN4I_HDMI_PAD_CTRL1_EMPCK_OPT		BIT(19)
+#define SUN4I_HDMI_PAD_CTRL1_REG_DEN		BIT(15)
+#define SUN4I_HDMI_PAD_CTRL1_REG_DENCK		BIT(14)
+#define SUN4I_HDMI_PAD_CTRL1_REG_EMP(n)		(((n) & 7) << 10)
+#define SUN4I_HDMI_PAD_CTRL1_HALVE_CLK		BIT(6)
+#define SUN4I_HDMI_PAD_CTRL1_REG_AMP(n)		(((n) & 7) << 3)
+
+#define SUN4I_HDMI_PLL_CTRL_REG		0x208
+#define SUN4I_HDMI_PLL_CTRL_PLL_EN		BIT(31)
+#define SUN4I_HDMI_PLL_CTRL_BWS			BIT(30)
+#define SUN4I_HDMI_PLL_CTRL_HV_IS_33		BIT(29)
+#define SUN4I_HDMI_PLL_CTRL_LDO1_EN		BIT(28)
+#define SUN4I_HDMI_PLL_CTRL_LDO2_EN		BIT(27)
+#define SUN4I_HDMI_PLL_CTRL_SDIV2		BIT(25)
+#define SUN4I_HDMI_PLL_CTRL_VCO_GAIN(n)		(((n) & 7) << 20)
+#define SUN4I_HDMI_PLL_CTRL_S(n)		(((n) & 7) << 17)
+#define SUN4I_HDMI_PLL_CTRL_CP_S(n)		(((n) & 0x1f) << 12)
+#define SUN4I_HDMI_PLL_CTRL_CS(n)		(((n) & 0xf) << 8)
+#define SUN4I_HDMI_PLL_CTRL_DIV(n)		(((n) & 0xf) << 4)
+#define SUN4I_HDMI_PLL_CTRL_DIV_MASK		GENMASK(7, 4)
+#define SUN4I_HDMI_PLL_CTRL_VCO_S(n)		((n) & 0xf)
+
+#define SUN4I_HDMI_PLL_DBG0_REG		0x20c
+#define SUN4I_HDMI_PLL_DBG0_TMDS_PARENT(n)	(((n) & 1) << 21)
+#define SUN4I_HDMI_PLL_DBG0_TMDS_PARENT_MASK	BIT(21)
+#define SUN4I_HDMI_PLL_DBG0_TMDS_PARENT_SHIFT	21
+
+#define SUN4I_HDMI_PKT_CTRL_REG(n)	(0x2f0 + (4 * (n)))
+#define SUN4I_HDMI_PKT_CTRL_TYPE(n, t)		((t) << (((n) % 4) * 4))
+
+#define SUN4I_HDMI_UNKNOWN_REG		0x300
+#define SUN4I_HDMI_UNKNOWN_INPUT_SYNC		BIT(27)
+
+#define SUN4I_HDMI_DDC_CTRL_REG		0x500
+#define SUN4I_HDMI_DDC_CTRL_ENABLE		BIT(31)
+#define SUN4I_HDMI_DDC_CTRL_START_CMD		BIT(30)
+#define SUN4I_HDMI_DDC_CTRL_FIFO_DIR_MASK	BIT(8)
+#define SUN4I_HDMI_DDC_CTRL_FIFO_DIR_READ	(0 << 8)
+#define SUN4I_HDMI_DDC_CTRL_RESET		BIT(0)
+
+#define SUN4I_HDMI_DDC_ADDR_REG		0x504
+#define SUN4I_HDMI_DDC_ADDR_SEGMENT(seg)	(((seg) & 0xff) << 24)
+#define SUN4I_HDMI_DDC_ADDR_EDDC(addr)		(((addr) & 0xff) << 16)
+#define SUN4I_HDMI_DDC_ADDR_OFFSET(off)		(((off) & 0xff) << 8)
+#define SUN4I_HDMI_DDC_ADDR_SLAVE(addr)		((addr) & 0xff)
+
+#define SUN4I_HDMI_DDC_FIFO_CTRL_REG	0x510
+#define SUN4I_HDMI_DDC_FIFO_CTRL_CLEAR		BIT(31)
+
+#define SUN4I_HDMI_DDC_FIFO_DATA_REG	0x518
+#define SUN4I_HDMI_DDC_BYTE_COUNT_REG	0x51c
+
+#define SUN4I_HDMI_DDC_CMD_REG		0x520
+#define SUN4I_HDMI_DDC_CMD_EXPLICIT_EDDC_READ	6
+
+#define SUN4I_HDMI_DDC_CLK_REG		0x528
+#define SUN4I_HDMI_DDC_CLK_M(m)			(((m) & 0x7) << 3)
+#define SUN4I_HDMI_DDC_CLK_N(n)			((n) & 0x7)
+
+#define SUN4I_HDMI_DDC_LINE_CTRL_REG	0x540
+#define SUN4I_HDMI_DDC_LINE_CTRL_SDA_ENABLE	BIT(9)
+#define SUN4I_HDMI_DDC_LINE_CTRL_SCL_ENABLE	BIT(8)
+
+#define SUN4I_HDMI_DDC_FIFO_SIZE	16
+
+enum sun4i_hdmi_pkt_type {
+	SUN4I_HDMI_PKT_AVI = 2,
+	SUN4I_HDMI_PKT_END = 15,
+};
+
+struct sun4i_hdmi {
+	struct drm_connector	connector;
+	struct drm_encoder	encoder;
+	struct device		*dev;
+
+	void __iomem		*base;
+
+	/* Parent clocks */
+	struct clk		*bus_clk;
+	struct clk		*mod_clk;
+	struct clk		*pll0_clk;
+	struct clk		*pll1_clk;
+
+	/* And the clocks we create */
+	struct clk		*ddc_clk;
+	struct clk		*tmds_clk;
+
+	struct sun4i_drv	*drv;
+
+	bool			hdmi_monitor;
+};
+
+int sun4i_ddc_create(struct sun4i_hdmi *hdmi, struct clk *clk);
+int sun4i_tmds_create(struct sun4i_hdmi *hdmi);
+
+#endif /* _SUN4I_HDMI_H_ */

drivers/gpu/drm/sun4i/sun4i_hdmi_ddc_clk.c

+/*
+ * Copyright (C) 2016 Free Electrons
+ * Copyright (C) 2016 NextThing Co
+ *
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * 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 <linux/clk-provider.h>
+
+#include "sun4i_tcon.h"
+#include "sun4i_hdmi.h"
+
+struct sun4i_ddc {
+	struct clk_hw		hw;
+	struct sun4i_hdmi	*hdmi;
+};
+
+static inline struct sun4i_ddc *hw_to_ddc(struct clk_hw *hw)
+{
+	return container_of(hw, struct sun4i_ddc, hw);
+}
+
+static unsigned long sun4i_ddc_calc_divider(unsigned long rate,
+					    unsigned long parent_rate,
+					    u8 *m, u8 *n)
+{
+	unsigned long best_rate = 0;
+	u8 best_m = 0, best_n = 0, _m, _n;
+
+	for (_m = 0; _m < 8; _m++) {
+		for (_n = 0; _n < 8; _n++) {
+			unsigned long tmp_rate;
+
+			tmp_rate = (((parent_rate / 2) / 10) >> _n) / (_m + 1);
+
+			if (tmp_rate > rate)
+				continue;
+
+			if (abs(rate - tmp_rate) < abs(rate - best_rate)) {
+				best_rate = tmp_rate;
+				best_m = _m;
+				best_n = _n;
+			}
+		}
+	}
+
+	if (m && n) {
+		*m = best_m;
+		*n = best_n;
+	}
+
+	return best_rate;
+}
+
+static long sun4i_ddc_round_rate(struct clk_hw *hw, unsigned long rate,
+				 unsigned long *prate)
+{
+	return sun4i_ddc_calc_divider(rate, *prate, NULL, NULL);
+}
+
+static unsigned long sun4i_ddc_recalc_rate(struct clk_hw *hw,
+					    unsigned long parent_rate)
+{
+	struct sun4i_ddc *ddc = hw_to_ddc(hw);
+	u32 reg;
+	u8 m, n;
+
+	reg = readl(ddc->hdmi->base + SUN4I_HDMI_DDC_CLK_REG);
+	m = (reg >> 3) & 0x7;
+	n = reg & 0x7;
+
+	return (((parent_rate / 2) / 10) >> n) / (m + 1);
+}
+
+static int sun4i_ddc_set_rate(struct clk_hw *hw, unsigned long rate,
+			      unsigned long parent_rate)
+{
+	struct sun4i_ddc *ddc = hw_to_ddc(hw);
+	u8 div_m, div_n;
+
+	sun4i_ddc_calc_divider(rate, parent_rate, &div_m, &div_n);
+
+	writel(SUN4I_HDMI_DDC_CLK_M(div_m) | SUN4I_HDMI_DDC_CLK_N(div_n),
+	       ddc->hdmi->base + SUN4I_HDMI_DDC_CLK_REG);
+
+	return 0;
+}
+
+static const struct clk_ops sun4i_ddc_ops = {
+	.recalc_rate	= sun4i_ddc_recalc_rate,
+	.round_rate	= sun4i_ddc_round_rate,
+	.set_rate	= sun4i_ddc_set_rate,
+};
+
+int sun4i_ddc_create(struct sun4i_hdmi *hdmi, struct clk *parent)
+{
+	struct clk_init_data init;
+	struct sun4i_ddc *ddc;
+	const char *parent_name;
+
+	parent_name = __clk_get_name(parent);
+	if (!parent_name)
+		return -ENODEV;
+
+	ddc = devm_kzalloc(hdmi->dev, sizeof(*ddc), GFP_KERNEL);
+	if (!ddc)
+		return -ENOMEM;
+
+	init.name = "hdmi-ddc";
+	init.ops = &sun4i_ddc_ops;
+	init.parent_names = &parent_name;
+	init.num_parents = 1;
+
+	ddc->hdmi = hdmi;
+	ddc->hw.init = &init;
+
+	hdmi->ddc_clk = devm_clk_register(hdmi->dev, &ddc->hw);
+	if (IS_ERR(hdmi->ddc_clk))
+		return PTR_ERR(hdmi->ddc_clk);
+
+	return 0;
+}

drivers/gpu/drm/sun4i/sun4i_hdmi_enc.c

+/*
+ * Copyright (C) 2016 Maxime Ripard
+ *
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * 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_helper.h>
+#include <drm/drm_edid.h>
+#include <drm/drm_encoder.h>
+#include <drm/drm_of.h>
+#include <drm/drm_panel.h>
+
+#include <linux/clk.h>
+#include <linux/component.h>
+#include <linux/iopoll.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+
+#include "sun4i_backend.h"
+#include "sun4i_crtc.h"
+#include "sun4i_drv.h"
+#include "sun4i_hdmi.h"
+#include "sun4i_tcon.h"
+
+#define DDC_SEGMENT_ADDR	0x30
+
+static inline struct sun4i_hdmi *
+drm_encoder_to_sun4i_hdmi(struct drm_encoder *encoder)
+{
+	return container_of(encoder, struct sun4i_hdmi,
+			    encoder);
+}
+
+static inline struct sun4i_hdmi *
+drm_connector_to_sun4i_hdmi(struct drm_connector *connector)
+{
+	return container_of(connector, struct sun4i_hdmi,
+			    connector);
+}
+
+static int sun4i_hdmi_setup_avi_infoframes(struct sun4i_hdmi *hdmi,
+					   struct drm_display_mode *mode)
+{
+	struct hdmi_avi_infoframe frame;
+	u8 buffer[17];
+	int i, ret;
+
+	ret = drm_hdmi_avi_infoframe_from_display_mode(&frame, mode);
+	if (ret < 0) {
+		DRM_ERROR("Failed to get infoframes from mode\n");
+		return ret;
+	}
+
+	ret = hdmi_avi_infoframe_pack(&frame, buffer, sizeof(buffer));
+	if (ret < 0) {
+		DRM_ERROR("Failed to pack infoframes\n");
+		return ret;
+	}
+
+	for (i = 0; i < sizeof(buffer); i++)
+		writeb(buffer[i], hdmi->base + SUN4I_HDMI_AVI_INFOFRAME_REG(i));
+
+	return 0;
+}
+
+static int sun4i_hdmi_atomic_check(struct drm_encoder *encoder,
+				   struct drm_crtc_state *crtc_state,
+				   struct drm_connector_state *conn_state)
+{
+	struct drm_display_mode *mode = &crtc_state->mode;
+
+	if (mode->flags & DRM_MODE_FLAG_DBLCLK)
+		return -EINVAL;
+
+	return 0;
+}
+
+static void sun4i_hdmi_disable(struct drm_encoder *encoder)
+{
+	struct sun4i_hdmi *hdmi = drm_encoder_to_sun4i_hdmi(encoder);
+	struct sun4i_crtc *crtc = drm_crtc_to_sun4i_crtc(encoder->crtc);
+	struct sun4i_tcon *tcon = crtc->tcon;
+	u32 val;
+
+	DRM_DEBUG_DRIVER("Disabling the HDMI Output\n");
+
+	val = readl(hdmi->base + SUN4I_HDMI_VID_CTRL_REG);
+	val &= ~SUN4I_HDMI_VID_CTRL_ENABLE;
+	writel(val, hdmi->base + SUN4I_HDMI_VID_CTRL_REG);
+
+	sun4i_tcon_channel_disable(tcon, 1);
+}
+
+static void sun4i_hdmi_enable(struct drm_encoder *encoder)
+{
+	struct drm_display_mode *mode = &encoder->crtc->state->adjusted_mode;
+	struct sun4i_hdmi *hdmi = drm_encoder_to_sun4i_hdmi(encoder);
+	struct sun4i_crtc *crtc = drm_crtc_to_sun4i_crtc(encoder->crtc);
+	struct sun4i_tcon *tcon = crtc->tcon;
+	u32 val = 0;
+
+	DRM_DEBUG_DRIVER("Enabling the HDMI Output\n");
+
+	sun4i_tcon_channel_enable(tcon, 1);
+
+	sun4i_hdmi_setup_avi_infoframes(hdmi, mode);
+	val |= SUN4I_HDMI_PKT_CTRL_TYPE(0, SUN4I_HDMI_PKT_AVI);
+	val |= SUN4I_HDMI_PKT_CTRL_TYPE(1, SUN4I_HDMI_PKT_END);
+	writel(val, hdmi->base + SUN4I_HDMI_PKT_CTRL_REG(0));
+
+	val = SUN4I_HDMI_VID_CTRL_ENABLE;
+	if (hdmi->hdmi_monitor)
+		val |= SUN4I_HDMI_VID_CTRL_HDMI_MODE;
+
+	writel(val, hdmi->base + SUN4I_HDMI_VID_CTRL_REG);
+}
+
+static void sun4i_hdmi_mode_set(struct drm_encoder *encoder,
+				struct drm_display_mode *mode,
+				struct drm_display_mode *adjusted_mode)
+{
+	struct sun4i_hdmi *hdmi = drm_encoder_to_sun4i_hdmi(encoder);
+	struct sun4i_crtc *crtc = drm_crtc_to_sun4i_crtc(encoder->crtc);
+	struct sun4i_tcon *tcon = crtc->tcon;
+	unsigned int x, y;
+	u32 val;
+
+	sun4i_tcon1_mode_set(tcon, mode);
+	sun4i_tcon_set_mux(tcon, 1, encoder);
+
+	clk_set_rate(tcon->sclk1, mode->crtc_clock * 1000);
+	clk_set_rate(hdmi->mod_clk, mode->crtc_clock * 1000);
+	clk_set_rate(hdmi->tmds_clk, mode->crtc_clock * 1000);
+
+	/* Set input sync enable */
+	writel(SUN4I_HDMI_UNKNOWN_INPUT_SYNC,
+	       hdmi->base + SUN4I_HDMI_UNKNOWN_REG);
+
+	/* Setup timing registers */
+	writel(SUN4I_HDMI_VID_TIMING_X(mode->hdisplay) |
+	       SUN4I_HDMI_VID_TIMING_Y(mode->vdisplay),
+	       hdmi->base + SUN4I_HDMI_VID_TIMING_ACT_REG);
+
+	x = mode->htotal - mode->hsync_start;
+	y = mode->vtotal - mode->vsync_start;
+	writel(SUN4I_HDMI_VID_TIMING_X(x) | SUN4I_HDMI_VID_TIMING_Y(y),
+	       hdmi->base + SUN4I_HDMI_VID_TIMING_BP_REG);
+
+	x = mode->hsync_start - mode->hdisplay;
+	y = mode->vsync_start - mode->vdisplay;
+	writel(SUN4I_HDMI_VID_TIMING_X(x) | SUN4I_HDMI_VID_TIMING_Y(y),
+	       hdmi->base + SUN4I_HDMI_VID_TIMING_FP_REG);
+
+	x = mode->hsync_end - mode->hsync_start;
+	y = mode->vsync_end - mode->vsync_start;
+	writel(SUN4I_HDMI_VID_TIMING_X(x) | SUN4I_HDMI_VID_TIMING_Y(y),
+	       hdmi->base + SUN4I_HDMI_VID_TIMING_SPW_REG);
+
+	val = SUN4I_HDMI_VID_TIMING_POL_TX_CLK;
+	if (mode->flags & DRM_MODE_FLAG_PHSYNC)
+		val |= SUN4I_HDMI_VID_TIMING_POL_HSYNC;
+
+	if (mode->flags & DRM_MODE_FLAG_PVSYNC)
+		val |= SUN4I_HDMI_VID_TIMING_POL_VSYNC;
+
+	writel(val, hdmi->base + SUN4I_HDMI_VID_TIMING_POL_REG);
+}
+
+static const struct drm_encoder_helper_funcs sun4i_hdmi_helper_funcs = {
+	.atomic_check	= sun4i_hdmi_atomic_check,
+	.disable	= sun4i_hdmi_disable,
+	.enable		= sun4i_hdmi_enable,
+	.mode_set	= sun4i_hdmi_mode_set,
+};
+
+static const struct drm_encoder_funcs sun4i_hdmi_funcs = {
+	.destroy	= drm_encoder_cleanup,
+};
+
+static int sun4i_hdmi_read_sub_block(struct sun4i_hdmi *hdmi,
+				     unsigned int blk, unsigned int offset,
+				     u8 *buf, unsigned int count)
+{
+	unsigned long reg;
+	int i;
+
+	reg = readl(hdmi->base + SUN4I_HDMI_DDC_CTRL_REG);
+	reg &= ~SUN4I_HDMI_DDC_CTRL_FIFO_DIR_MASK;
+	writel(reg | SUN4I_HDMI_DDC_CTRL_FIFO_DIR_READ,
+	       hdmi->base + SUN4I_HDMI_DDC_CTRL_REG);
+
+	writel(SUN4I_HDMI_DDC_ADDR_SEGMENT(offset >> 8) |
+	       SUN4I_HDMI_DDC_ADDR_EDDC(DDC_SEGMENT_ADDR << 1) |
+	       SUN4I_HDMI_DDC_ADDR_OFFSET(offset) |
+	       SUN4I_HDMI_DDC_ADDR_SLAVE(DDC_ADDR),
+	       hdmi->base + SUN4I_HDMI_DDC_ADDR_REG);
+
+	reg = readl(hdmi->base + SUN4I_HDMI_DDC_FIFO_CTRL_REG);
+	writel(reg | SUN4I_HDMI_DDC_FIFO_CTRL_CLEAR,
+	       hdmi->base + SUN4I_HDMI_DDC_FIFO_CTRL_REG);
+
+	writel(count, hdmi->base + SUN4I_HDMI_DDC_BYTE_COUNT_REG);
+	writel(SUN4I_HDMI_DDC_CMD_EXPLICIT_EDDC_READ,
+	       hdmi->base + SUN4I_HDMI_DDC_CMD_REG);
+
+	reg = readl(hdmi->base + SUN4I_HDMI_DDC_CTRL_REG);
+	writel(reg | SUN4I_HDMI_DDC_CTRL_START_CMD,
+	       hdmi->base + SUN4I_HDMI_DDC_CTRL_REG);
+
+	if (readl_poll_timeout(hdmi->base + SUN4I_HDMI_DDC_CTRL_REG, reg,
+			       !(reg & SUN4I_HDMI_DDC_CTRL_START_CMD),
+			       100, 100000))
+		return -EIO;
+
+	for (i = 0; i < count; i++)
+		buf[i] = readb(hdmi->base + SUN4I_HDMI_DDC_FIFO_DATA_REG);
+
+	return 0;
+}
+
+static int sun4i_hdmi_read_edid_block(void *data, u8 *buf, unsigned int blk,
+				      size_t length)
+{
+	struct sun4i_hdmi *hdmi = data;
+	int retry = 2, i;
+
+	do {
+		for (i = 0; i < length; i += SUN4I_HDMI_DDC_FIFO_SIZE) {
+			unsigned char offset = blk * EDID_LENGTH + i;
+			unsigned int count = min((unsigned int)SUN4I_HDMI_DDC_FIFO_SIZE,
+						 length - i);
+			int ret;
+
+			ret = sun4i_hdmi_read_sub_block(hdmi, blk, offset,
+							buf + i, count);
+			if (ret)
+				return ret;
+		}
+	} while (!drm_edid_block_valid(buf, blk, true, NULL) && (retry--));
+
+	return 0;
+}
+
+static int sun4i_hdmi_get_modes(struct drm_connector *connector)
+{
+	struct sun4i_hdmi *hdmi = drm_connector_to_sun4i_hdmi(connector);
+	unsigned long reg;
+	struct edid *edid;
+	int ret;
+
+	/* Reset i2c controller */
+	writel(SUN4I_HDMI_DDC_CTRL_ENABLE | SUN4I_HDMI_DDC_CTRL_RESET,
+	       hdmi->base + SUN4I_HDMI_DDC_CTRL_REG);
+	if (readl_poll_timeout(hdmi->base + SUN4I_HDMI_DDC_CTRL_REG, reg,
+			       !(reg & SUN4I_HDMI_DDC_CTRL_RESET),
+			       100, 2000))
+		return -EIO;
+
+	writel(SUN4I_HDMI_DDC_LINE_CTRL_SDA_ENABLE |
+	       SUN4I_HDMI_DDC_LINE_CTRL_SCL_ENABLE,
+	       hdmi->base + SUN4I_HDMI_DDC_LINE_CTRL_REG);
+
+	clk_prepare_enable(hdmi->ddc_clk);
+	clk_set_rate(hdmi->ddc_clk, 100000);
+
+	edid = drm_do_get_edid(connector, sun4i_hdmi_read_edid_block, hdmi);
+	if (!edid)
+		return 0;
+
+	hdmi->hdmi_monitor = drm_detect_hdmi_monitor(edid);
+	DRM_DEBUG_DRIVER("Monitor is %s monitor\n",
+			 hdmi->hdmi_monitor ? "an HDMI" : "a DVI");
+
+	drm_mode_connector_update_edid_property(connector, edid);
+	ret = drm_add_edid_modes(connector, edid);
+	kfree(edid);
+
+	clk_disable_unprepare(hdmi->ddc_clk);
+
+	return ret;
+}
+
+static const struct drm_connector_helper_funcs sun4i_hdmi_connector_helper_funcs = {
+	.get_modes	= sun4i_hdmi_get_modes,
+};
+
+static enum drm_connector_status
+sun4i_hdmi_connector_detect(struct drm_connector *connector, bool force)
+{
+	struct sun4i_hdmi *hdmi = drm_connector_to_sun4i_hdmi(connector);
+	unsigned long reg;
+
+	if (readl_poll_timeout(hdmi->base + SUN4I_HDMI_HPD_REG, reg,
+			       reg & SUN4I_HDMI_HPD_HIGH,
+			       0, 500000))
+		return connector_status_disconnected;
+
+	return connector_status_connected;
+}
+
+static const struct drm_connector_funcs sun4i_hdmi_connector_funcs = {
+	.dpms			= drm_atomic_helper_connector_dpms,
+	.detect			= sun4i_hdmi_connector_detect,
+	.fill_modes		= drm_helper_probe_single_connector_modes,
+	.destroy		= drm_connector_cleanup,
+	.reset			= drm_atomic_helper_connector_reset,
+	.atomic_duplicate_state	= drm_atomic_helper_connector_duplicate_state,
+	.atomic_destroy_state	= drm_atomic_helper_connector_destroy_state,
+};
+
+static int sun4i_hdmi_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 sun4i_hdmi *hdmi;
+	struct resource *res;
+	u32 reg;
+	int ret;
+
+	hdmi = devm_kzalloc(dev, sizeof(*hdmi), GFP_KERNEL);
+	if (!hdmi)
+		return -ENOMEM;
+	dev_set_drvdata(dev, hdmi);
+	hdmi->dev = dev;
+	hdmi->drv = drv;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	hdmi->base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(hdmi->base)) {
+		dev_err(dev, "Couldn't map the HDMI encoder registers\n");
+		return PTR_ERR(hdmi->base);
+	}
+
+	hdmi->bus_clk = devm_clk_get(dev, "ahb");
+	if (IS_ERR(hdmi->bus_clk)) {
+		dev_err(dev, "Couldn't get the HDMI bus clock\n");
+		return PTR_ERR(hdmi->bus_clk);
+	}
+	clk_prepare_enable(hdmi->bus_clk);
+
+	hdmi->mod_clk = devm_clk_get(dev, "mod");
+	if (IS_ERR(hdmi->mod_clk)) {
+		dev_err(dev, "Couldn't get the HDMI mod clock\n");
+		return PTR_ERR(hdmi->mod_clk);
+	}
+	clk_prepare_enable(hdmi->mod_clk);
+
+	hdmi->pll0_clk = devm_clk_get(dev, "pll-0");
+	if (IS_ERR(hdmi->pll0_clk)) {
+		dev_err(dev, "Couldn't get the HDMI PLL 0 clock\n");
+		return PTR_ERR(hdmi->pll0_clk);
+	}
+
+	hdmi->pll1_clk = devm_clk_get(dev, "pll-1");
+	if (IS_ERR(hdmi->pll1_clk)) {
+		dev_err(dev, "Couldn't get the HDMI PLL 1 clock\n");
+		return PTR_ERR(hdmi->pll1_clk);
+	}
+
+	ret = sun4i_tmds_create(hdmi);
+	if (ret) {
+		dev_err(dev, "Couldn't create the TMDS clock\n");
+		return ret;
+	}
+
+	writel(SUN4I_HDMI_CTRL_ENABLE, hdmi->base + SUN4I_HDMI_CTRL_REG);
+
+	writel(SUN4I_HDMI_PAD_CTRL0_TXEN | SUN4I_HDMI_PAD_CTRL0_CKEN |
+	       SUN4I_HDMI_PAD_CTRL0_PWENG | SUN4I_HDMI_PAD_CTRL0_PWEND |
+	       SUN4I_HDMI_PAD_CTRL0_PWENC | SUN4I_HDMI_PAD_CTRL0_LDODEN |
+	       SUN4I_HDMI_PAD_CTRL0_LDOCEN | SUN4I_HDMI_PAD_CTRL0_BIASEN,
+	       hdmi->base + SUN4I_HDMI_PAD_CTRL0_REG);
+
+	/*
+	 * We can't just initialize the register there, we need to
+	 * protect the clock bits that have already been read out and
+	 * cached by the clock framework.
+	 */
+	reg = readl(hdmi->base + SUN4I_HDMI_PAD_CTRL1_REG);
+	reg &= SUN4I_HDMI_PAD_CTRL1_HALVE_CLK;
+	reg |= SUN4I_HDMI_PAD_CTRL1_REG_AMP(6) |
+		SUN4I_HDMI_PAD_CTRL1_REG_EMP(2) |
+		SUN4I_HDMI_PAD_CTRL1_REG_DENCK |
+		SUN4I_HDMI_PAD_CTRL1_REG_DEN |
+		SUN4I_HDMI_PAD_CTRL1_EMPCK_OPT |
+		SUN4I_HDMI_PAD_CTRL1_EMP_OPT |
+		SUN4I_HDMI_PAD_CTRL1_AMPCK_OPT |
+		SUN4I_HDMI_PAD_CTRL1_AMP_OPT;
+	writel(reg, hdmi->base + SUN4I_HDMI_PAD_CTRL1_REG);
+
+	reg = readl(hdmi->base + SUN4I_HDMI_PLL_CTRL_REG);
+	reg &= SUN4I_HDMI_PLL_CTRL_DIV_MASK;
+	reg |= SUN4I_HDMI_PLL_CTRL_VCO_S(8) | SUN4I_HDMI_PLL_CTRL_CS(7) |
+		SUN4I_HDMI_PLL_CTRL_CP_S(15) | SUN4I_HDMI_PLL_CTRL_S(7) |
+		SUN4I_HDMI_PLL_CTRL_VCO_GAIN(4) | SUN4I_HDMI_PLL_CTRL_SDIV2 |
+		SUN4I_HDMI_PLL_CTRL_LDO2_EN | SUN4I_HDMI_PLL_CTRL_LDO1_EN |
+		SUN4I_HDMI_PLL_CTRL_HV_IS_33 | SUN4I_HDMI_PLL_CTRL_BWS |
+		SUN4I_HDMI_PLL_CTRL_PLL_EN;
+	writel(reg, hdmi->base + SUN4I_HDMI_PLL_CTRL_REG);
+
+	ret = sun4i_ddc_create(hdmi, hdmi->tmds_clk);
+	if (ret) {
+		dev_err(dev, "Couldn't create the DDC clock\n");
+		return ret;
+	}
+
+	drm_encoder_helper_add(&hdmi->encoder,
+			       &sun4i_hdmi_helper_funcs);
+	ret = drm_encoder_init(drm,
+			       &hdmi->encoder,
+			       &sun4i_hdmi_funcs,
+			       DRM_MODE_ENCODER_TMDS,
+			       NULL);
+	if (ret) {
+		dev_err(dev, "Couldn't initialise the HDMI encoder\n");
+		return ret;
+	}
+
+	hdmi->encoder.possible_crtcs = drm_of_find_possible_crtcs(drm,
+								  dev->of_node);
+	if (!hdmi->encoder.possible_crtcs)
+		return -EPROBE_DEFER;
+
+	drm_connector_helper_add(&hdmi->connector,
+				 &sun4i_hdmi_connector_helper_funcs);
+	ret = drm_connector_init(drm, &hdmi->connector,
+				 &sun4i_hdmi_connector_funcs,
+				 DRM_MODE_CONNECTOR_HDMIA);
+	if (ret) {
+		dev_err(dev,
+			"Couldn't initialise the HDMI connector\n");
+		goto err_cleanup_connector;
+	}
+
+	/* There is no HPD interrupt, so we need to poll the controller */
+	hdmi->connector.polled = DRM_CONNECTOR_POLL_CONNECT |
+		DRM_CONNECTOR_POLL_DISCONNECT;
+
+	drm_mode_connector_attach_encoder(&hdmi->connector, &hdmi->encoder);
+
+	return 0;
+
+err_cleanup_connector:
+	drm_encoder_cleanup(&hdmi->encoder);
+	return ret;
+}
+
+static void sun4i_hdmi_unbind(struct device *dev, struct device *master,
+			    void *data)
+{
+	struct sun4i_hdmi *hdmi = dev_get_drvdata(dev);
+
+	drm_connector_cleanup(&hdmi->connector);
+	drm_encoder_cleanup(&hdmi->encoder);
+}
+
+static const struct component_ops sun4i_hdmi_ops = {
+	.bind	= sun4i_hdmi_bind,
+	.unbind	= sun4i_hdmi_unbind,
+};
+
+static int sun4i_hdmi_probe(struct platform_device *pdev)
+{
+	return component_add(&pdev->dev, &sun4i_hdmi_ops);
+}
+
+static int sun4i_hdmi_remove(struct platform_device *pdev)
+{
+	component_del(&pdev->dev, &sun4i_hdmi_ops);
+
+	return 0;
+}
+
+static const struct of_device_id sun4i_hdmi_of_table[] = {
+	{ .compatible = "allwinner,sun5i-a10s-hdmi" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, sun4i_hdmi_of_table);
+
+static struct platform_driver sun4i_hdmi_driver = {
+	.probe		= sun4i_hdmi_probe,
+	.remove		= sun4i_hdmi_remove,
+	.driver		= {
+		.name		= "sun4i-hdmi",
+		.of_match_table	= sun4i_hdmi_of_table,
+	},
+};
+module_platform_driver(sun4i_hdmi_driver);
+
+MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
+MODULE_DESCRIPTION("Allwinner A10 HDMI Driver");
+MODULE_LICENSE("GPL");

drivers/gpu/drm/sun4i/sun4i_hdmi_tmds_clk.c

+/*
+ * Copyright (C) 2016 Free Electrons
+ * Copyright (C) 2016 NextThing Co
+ *
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * 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 <linux/clk-provider.h>
+
+#include "sun4i_tcon.h"
+#include "sun4i_hdmi.h"
+
+struct sun4i_tmds {
+	struct clk_hw		hw;
+	struct sun4i_hdmi	*hdmi;
+};
+
+static inline struct sun4i_tmds *hw_to_tmds(struct clk_hw *hw)
+{
+	return container_of(hw, struct sun4i_tmds, hw);
+}
+
+
+static unsigned long sun4i_tmds_calc_divider(unsigned long rate,
+					     unsigned long parent_rate,
+					     u8 *div,
+					     bool *half)
+{
+	unsigned long best_rate = 0;
+	u8 best_m = 0, m;
+	bool is_double;
+
+	for (m = 1; m < 16; m++) {
+		u8 d;
+
+		for (d = 1; d < 3; d++) {
+			unsigned long tmp_rate;
+
+			tmp_rate = parent_rate / m / d;
+
+			if (tmp_rate > rate)
+				continue;
+
+			if (!best_rate ||
+			    (rate - tmp_rate) < (rate - best_rate)) {
+				best_rate = tmp_rate;
+				best_m = m;
+				is_double = d;
+			}
+		}
+	}
+
+	if (div && half) {
+		*div = best_m;
+		*half = is_double;
+	}
+
+	return best_rate;
+}
+
+
+static int sun4i_tmds_determine_rate(struct clk_hw *hw,
+				     struct clk_rate_request *req)
+{
+	struct clk_hw *parent;
+	unsigned long best_parent = 0;
+	unsigned long rate = req->rate;
+	int best_div = 1, best_half = 1;
+	int i, j;
+
+	/*
+	 * We only consider PLL3, since the TCON is very likely to be
+	 * clocked from it, and to have the same rate than our HDMI
+	 * clock, so we should not need to do anything.
+	 */
+
+	parent = clk_hw_get_parent_by_index(hw, 0);
+	if (!parent)
+		return -EINVAL;
+
+	for (i = 1; i < 3; i++) {
+		for (j = 1; j < 16; j++) {
+			unsigned long ideal = rate * i * j;
+			unsigned long rounded;
+
+			rounded = clk_hw_round_rate(parent, ideal);
+
+			if (rounded == ideal) {
+				best_parent = rounded;
+				best_half = i;
+				best_div = j;
+				goto out;
+			}
+
+			if (abs(rate - rounded / i) <
+			    abs(rate - best_parent / best_div)) {
+				best_parent = rounded;
+				best_div = i;
+			}
+		}
+	}
+
+out:
+	req->rate = best_parent / best_half / best_div;
+	req->best_parent_rate = best_parent;
+	req->best_parent_hw = parent;
+
+	return 0;
+}
+
+static unsigned long sun4i_tmds_recalc_rate(struct clk_hw *hw,
+					    unsigned long parent_rate)
+{
+	struct sun4i_tmds *tmds = hw_to_tmds(hw);
+	u32 reg;
+
+	reg = readl(tmds->hdmi->base + SUN4I_HDMI_PAD_CTRL1_REG);
+	if (reg & SUN4I_HDMI_PAD_CTRL1_HALVE_CLK)
+		parent_rate /= 2;
+
+	reg = readl(tmds->hdmi->base + SUN4I_HDMI_PLL_CTRL_REG);
+	reg = (reg >> 4) & 0xf;
+	if (!reg)
+		reg = 1;
+
+	return parent_rate / reg;
+}
+
+static int sun4i_tmds_set_rate(struct clk_hw *hw, unsigned long rate,
+			       unsigned long parent_rate)
+{
+	struct sun4i_tmds *tmds = hw_to_tmds(hw);
+	bool half;
+	u32 reg;
+	u8 div;
+
+	sun4i_tmds_calc_divider(rate, parent_rate, &div, &half);
+
+	reg = readl(tmds->hdmi->base + SUN4I_HDMI_PAD_CTRL1_REG);
+	reg &= ~SUN4I_HDMI_PAD_CTRL1_HALVE_CLK;
+	if (half)
+		reg |= SUN4I_HDMI_PAD_CTRL1_HALVE_CLK;
+	writel(reg, tmds->hdmi->base + SUN4I_HDMI_PAD_CTRL1_REG);
+
+	reg = readl(tmds->hdmi->base + SUN4I_HDMI_PLL_CTRL_REG);
+	reg &= ~SUN4I_HDMI_PLL_CTRL_DIV_MASK;
+	writel(reg | SUN4I_HDMI_PLL_CTRL_DIV(div),
+	       tmds->hdmi->base + SUN4I_HDMI_PLL_CTRL_REG);
+
+	return 0;
+}
+
+static u8 sun4i_tmds_get_parent(struct clk_hw *hw)
+{
+	struct sun4i_tmds *tmds = hw_to_tmds(hw);
+	u32 reg;
+
+	reg = readl(tmds->hdmi->base + SUN4I_HDMI_PLL_DBG0_REG);
+	return ((reg & SUN4I_HDMI_PLL_DBG0_TMDS_PARENT_MASK) >>
+		SUN4I_HDMI_PLL_DBG0_TMDS_PARENT_SHIFT);
+}
+
+static int sun4i_tmds_set_parent(struct clk_hw *hw, u8 index)
+{
+	struct sun4i_tmds *tmds = hw_to_tmds(hw);
+	u32 reg;
+
+	if (index > 1)
+		return -EINVAL;
+
+	reg = readl(tmds->hdmi->base + SUN4I_HDMI_PLL_DBG0_REG);
+	reg &= ~SUN4I_HDMI_PLL_DBG0_TMDS_PARENT_MASK;
+	writel(reg | SUN4I_HDMI_PLL_DBG0_TMDS_PARENT(index),
+	       tmds->hdmi->base + SUN4I_HDMI_PLL_DBG0_REG);
+
+	return 0;
+}
+
+static const struct clk_ops sun4i_tmds_ops = {
+	.determine_rate	= sun4i_tmds_determine_rate,
+	.recalc_rate	= sun4i_tmds_recalc_rate,
+	.set_rate	= sun4i_tmds_set_rate,
+
+	.get_parent	= sun4i_tmds_get_parent,
+	.set_parent	= sun4i_tmds_set_parent,
+};
+
+int sun4i_tmds_create(struct sun4i_hdmi *hdmi)
+{
+	struct clk_init_data init;
+	struct sun4i_tmds *tmds;
+	const char *parents[2];
+
+	parents[0] = __clk_get_name(hdmi->pll0_clk);
+	if (!parents[0])
+		return -ENODEV;
+
+	parents[1] = __clk_get_name(hdmi->pll1_clk);
+	if (!parents[1])
+		return -ENODEV;
+
+	tmds = devm_kzalloc(hdmi->dev, sizeof(*tmds), GFP_KERNEL);
+	if (!tmds)
+		return -ENOMEM;
+
+	init.name = "hdmi-tmds";
+	init.ops = &sun4i_tmds_ops;
+	init.parent_names = parents;
+	init.num_parents = 2;
+	init.flags = CLK_SET_RATE_PARENT;
+
+	tmds->hdmi = hdmi;
+	tmds->hw.init = &init;
+
+	hdmi->tmds_clk = devm_clk_register(hdmi->dev, &tmds->hw);
+	if (IS_ERR(hdmi->tmds_clk))
+		return PTR_ERR(hdmi->tmds_clk);
+
+	return 0;
+}