1 /*
2  * Allwinner DW HDMI bridge
3  *
4  * (C) Copyright 2017 Jernej Skrabec <jernej.skrabec@siol.net>
5  *
6  * SPDX-License-Identifier:	GPL-2.0+
7  */
8 
9 #include <common.h>
10 #include <display.h>
11 #include <dm.h>
12 #include <dw_hdmi.h>
13 #include <edid.h>
14 #include <asm/io.h>
15 #include <asm/arch/clock.h>
16 #include <asm/arch/lcdc.h>
17 
18 struct sunxi_dw_hdmi_priv {
19 	struct dw_hdmi hdmi;
20 	int mux;
21 };
22 
23 struct sunxi_hdmi_phy {
24 	u32 pol;
25 	u32 res1[3];
26 	u32 read_en;
27 	u32 unscramble;
28 	u32 res2[2];
29 	u32 ctrl;
30 	u32 unk1;
31 	u32 unk2;
32 	u32 pll;
33 	u32 clk;
34 	u32 unk3;
35 	u32 status;
36 };
37 
38 #define HDMI_PHY_OFFS 0x10000
39 
40 static int sunxi_dw_hdmi_get_divider(uint clock)
41 {
42 	/*
43 	 * Due to missing documentaion of HDMI PHY, we know correct
44 	 * settings only for following four PHY dividers. Select one
45 	 * based on clock speed.
46 	 */
47 	if (clock <= 27000000)
48 		return 11;
49 	else if (clock <= 74250000)
50 		return 4;
51 	else if (clock <= 148500000)
52 		return 2;
53 	else
54 		return 1;
55 }
56 
57 static void sunxi_dw_hdmi_phy_init(void)
58 {
59 	struct sunxi_hdmi_phy * const phy =
60 		(struct sunxi_hdmi_phy *)(SUNXI_HDMI_BASE + HDMI_PHY_OFFS);
61 	unsigned long tmo;
62 	u32 tmp;
63 
64 	/*
65 	 * HDMI PHY settings are taken as-is from Allwinner BSP code.
66 	 * There is no documentation.
67 	 */
68 	writel(0, &phy->ctrl);
69 	setbits_le32(&phy->ctrl, BIT(0));
70 	udelay(5);
71 	setbits_le32(&phy->ctrl, BIT(16));
72 	setbits_le32(&phy->ctrl, BIT(1));
73 	udelay(10);
74 	setbits_le32(&phy->ctrl, BIT(2));
75 	udelay(5);
76 	setbits_le32(&phy->ctrl, BIT(3));
77 	udelay(40);
78 	setbits_le32(&phy->ctrl, BIT(19));
79 	udelay(100);
80 	setbits_le32(&phy->ctrl, BIT(18));
81 	setbits_le32(&phy->ctrl, 7 << 4);
82 
83 	/* Note that Allwinner code doesn't fail in case of timeout */
84 	tmo = timer_get_us() + 2000;
85 	while ((readl(&phy->status) & 0x80) == 0) {
86 		if (timer_get_us() > tmo) {
87 			printf("Warning: HDMI PHY init timeout!\n");
88 			break;
89 		}
90 	}
91 
92 	setbits_le32(&phy->ctrl, 0xf << 8);
93 	setbits_le32(&phy->ctrl, BIT(7));
94 
95 	writel(0x39dc5040, &phy->pll);
96 	writel(0x80084343, &phy->clk);
97 	udelay(10000);
98 	writel(1, &phy->unk3);
99 	setbits_le32(&phy->pll, BIT(25));
100 	udelay(100000);
101 	tmp = (readl(&phy->status) & 0x1f800) >> 11;
102 	setbits_le32(&phy->pll, BIT(31) | BIT(30));
103 	setbits_le32(&phy->pll, tmp);
104 	writel(0x01FF0F7F, &phy->ctrl);
105 	writel(0x80639000, &phy->unk1);
106 	writel(0x0F81C405, &phy->unk2);
107 
108 	/* enable read access to HDMI controller */
109 	writel(0x54524545, &phy->read_en);
110 	/* descramble register offsets */
111 	writel(0x42494E47, &phy->unscramble);
112 }
113 
114 static int sunxi_dw_hdmi_get_plug_in_status(void)
115 {
116 	struct sunxi_hdmi_phy * const phy =
117 		(struct sunxi_hdmi_phy *)(SUNXI_HDMI_BASE + HDMI_PHY_OFFS);
118 
119 	return !!(readl(&phy->status) & (1 << 19));
120 }
121 
122 static int sunxi_dw_hdmi_wait_for_hpd(void)
123 {
124 	ulong start;
125 
126 	start = get_timer(0);
127 	do {
128 		if (sunxi_dw_hdmi_get_plug_in_status())
129 			return 0;
130 		udelay(100);
131 	} while (get_timer(start) < 300);
132 
133 	return -1;
134 }
135 
136 static void sunxi_dw_hdmi_phy_set(uint clock)
137 {
138 	struct sunxi_hdmi_phy * const phy =
139 		(struct sunxi_hdmi_phy *)(SUNXI_HDMI_BASE + HDMI_PHY_OFFS);
140 	int div = sunxi_dw_hdmi_get_divider(clock);
141 	u32 tmp;
142 
143 	/*
144 	 * Unfortunately, we don't know much about those magic
145 	 * numbers. They are taken from Allwinner BSP driver.
146 	 */
147 	switch (div) {
148 	case 1:
149 		writel(0x30dc5fc0, &phy->pll);
150 		writel(0x800863C0, &phy->clk);
151 		mdelay(10);
152 		writel(0x00000001, &phy->unk3);
153 		setbits_le32(&phy->pll, BIT(25));
154 		mdelay(200);
155 		tmp = (readl(&phy->status) & 0x1f800) >> 11;
156 		setbits_le32(&phy->pll, BIT(31) | BIT(30));
157 		if (tmp < 0x3d)
158 			setbits_le32(&phy->pll, tmp + 2);
159 		else
160 			setbits_le32(&phy->pll, 0x3f);
161 		mdelay(100);
162 		writel(0x01FFFF7F, &phy->ctrl);
163 		writel(0x8063b000, &phy->unk1);
164 		writel(0x0F8246B5, &phy->unk2);
165 		break;
166 	case 2:
167 		writel(0x39dc5040, &phy->pll);
168 		writel(0x80084381, &phy->clk);
169 		mdelay(10);
170 		writel(0x00000001, &phy->unk3);
171 		setbits_le32(&phy->pll, BIT(25));
172 		mdelay(100);
173 		tmp = (readl(&phy->status) & 0x1f800) >> 11;
174 		setbits_le32(&phy->pll, BIT(31) | BIT(30));
175 		setbits_le32(&phy->pll, tmp);
176 		writel(0x01FFFF7F, &phy->ctrl);
177 		writel(0x8063a800, &phy->unk1);
178 		writel(0x0F81C485, &phy->unk2);
179 		break;
180 	case 4:
181 		writel(0x39dc5040, &phy->pll);
182 		writel(0x80084343, &phy->clk);
183 		mdelay(10);
184 		writel(0x00000001, &phy->unk3);
185 		setbits_le32(&phy->pll, BIT(25));
186 		mdelay(100);
187 		tmp = (readl(&phy->status) & 0x1f800) >> 11;
188 		setbits_le32(&phy->pll, BIT(31) | BIT(30));
189 		setbits_le32(&phy->pll, tmp);
190 		writel(0x01FFFF7F, &phy->ctrl);
191 		writel(0x8063b000, &phy->unk1);
192 		writel(0x0F81C405, &phy->unk2);
193 		break;
194 	case 11:
195 		writel(0x39dc5040, &phy->pll);
196 		writel(0x8008430a, &phy->clk);
197 		mdelay(10);
198 		writel(0x00000001, &phy->unk3);
199 		setbits_le32(&phy->pll, BIT(25));
200 		mdelay(100);
201 		tmp = (readl(&phy->status) & 0x1f800) >> 11;
202 		setbits_le32(&phy->pll, BIT(31) | BIT(30));
203 		setbits_le32(&phy->pll, tmp);
204 		writel(0x01FFFF7F, &phy->ctrl);
205 		writel(0x8063b000, &phy->unk1);
206 		writel(0x0F81C405, &phy->unk2);
207 		break;
208 	}
209 }
210 
211 static void sunxi_dw_hdmi_pll_set(uint clk_khz)
212 {
213 	int value, n, m, div = 0, diff;
214 	int best_n = 0, best_m = 0, best_diff = 0x0FFFFFFF;
215 
216 	div = sunxi_dw_hdmi_get_divider(clk_khz * 1000);
217 
218 	/*
219 	 * Find the lowest divider resulting in a matching clock. If there
220 	 * is no match, pick the closest lower clock, as monitors tend to
221 	 * not sync to higher frequencies.
222 	 */
223 	for (m = 1; m <= 16; m++) {
224 		n = (m * div * clk_khz) / 24000;
225 
226 		if ((n >= 1) && (n <= 128)) {
227 			value = (24000 * n) / m / div;
228 			diff = clk_khz - value;
229 			if (diff < best_diff) {
230 				best_diff = diff;
231 				best_m = m;
232 				best_n = n;
233 			}
234 		}
235 	}
236 
237 	clock_set_pll3_factors(best_m, best_n);
238 	debug("dotclock: %dkHz = %dkHz: (24MHz * %d) / %d / %d\n",
239 	      clk_khz, (clock_get_pll3() / 1000) / div,
240 	      best_n, best_m, div);
241 }
242 
243 static void sunxi_dw_hdmi_lcdc_init(int mux, const struct display_timing *edid,
244 				    int bpp)
245 {
246 	struct sunxi_ccm_reg * const ccm =
247 		(struct sunxi_ccm_reg *)SUNXI_CCM_BASE;
248 	int div = sunxi_dw_hdmi_get_divider(edid->pixelclock.typ);
249 	struct sunxi_lcdc_reg *lcdc;
250 
251 	if (mux == 0) {
252 		lcdc = (struct sunxi_lcdc_reg *)SUNXI_LCD0_BASE;
253 
254 		/* Reset off */
255 		setbits_le32(&ccm->ahb_reset1_cfg, 1 << AHB_RESET_OFFSET_LCD0);
256 
257 		/* Clock on */
258 		setbits_le32(&ccm->ahb_gate1, 1 << AHB_GATE_OFFSET_LCD0);
259 		writel(CCM_LCD0_CTRL_GATE | CCM_LCD0_CTRL_M(div),
260 		       &ccm->lcd0_clk_cfg);
261 	} else {
262 		lcdc = (struct sunxi_lcdc_reg *)SUNXI_LCD1_BASE;
263 
264 		/* Reset off */
265 		setbits_le32(&ccm->ahb_reset1_cfg, 1 << AHB_RESET_OFFSET_LCD1);
266 
267 		/* Clock on */
268 		setbits_le32(&ccm->ahb_gate1, 1 << AHB_GATE_OFFSET_LCD1);
269 		writel(CCM_LCD1_CTRL_GATE | CCM_LCD1_CTRL_M(div),
270 		       &ccm->lcd1_clk_cfg);
271 	}
272 
273 	lcdc_init(lcdc);
274 	lcdc_tcon1_mode_set(lcdc, edid, false, false);
275 	lcdc_enable(lcdc, bpp);
276 }
277 
278 static int sunxi_dw_hdmi_phy_cfg(struct dw_hdmi *hdmi, uint mpixelclock)
279 {
280 	sunxi_dw_hdmi_pll_set(mpixelclock/1000);
281 	sunxi_dw_hdmi_phy_set(mpixelclock);
282 
283 	return 0;
284 }
285 
286 static int sunxi_dw_hdmi_read_edid(struct udevice *dev, u8 *buf, int buf_size)
287 {
288 	struct sunxi_dw_hdmi_priv *priv = dev_get_priv(dev);
289 
290 	return dw_hdmi_read_edid(&priv->hdmi, buf, buf_size);
291 }
292 
293 static int sunxi_dw_hdmi_enable(struct udevice *dev, int panel_bpp,
294 				const struct display_timing *edid)
295 {
296 	struct sunxi_hdmi_phy * const phy =
297 		(struct sunxi_hdmi_phy *)(SUNXI_HDMI_BASE + HDMI_PHY_OFFS);
298 	struct sunxi_dw_hdmi_priv *priv = dev_get_priv(dev);
299 	int ret;
300 
301 	ret = dw_hdmi_enable(&priv->hdmi, edid);
302 	if (ret)
303 		return ret;
304 
305 	sunxi_dw_hdmi_lcdc_init(priv->mux, edid, panel_bpp);
306 
307 	if (edid->flags & DISPLAY_FLAGS_HSYNC_LOW)
308 		setbits_le32(&phy->pol, 0x200);
309 
310 	if (edid->flags & DISPLAY_FLAGS_VSYNC_LOW)
311 		setbits_le32(&phy->pol, 0x100);
312 
313 	setbits_le32(&phy->ctrl, 0xf << 12);
314 
315 	/*
316 	 * This is last hdmi access before boot, so scramble addresses
317 	 * again or othwerwise BSP driver won't work. Dummy read is
318 	 * needed or otherwise last write doesn't get written correctly.
319 	 */
320 	(void)readb(SUNXI_HDMI_BASE);
321 	writel(0, &phy->unscramble);
322 
323 	return 0;
324 }
325 
326 static int sunxi_dw_hdmi_probe(struct udevice *dev)
327 {
328 	struct display_plat *uc_plat = dev_get_uclass_platdata(dev);
329 	struct sunxi_dw_hdmi_priv *priv = dev_get_priv(dev);
330 	struct sunxi_ccm_reg * const ccm =
331 		(struct sunxi_ccm_reg *)SUNXI_CCM_BASE;
332 	int ret;
333 
334 	/* Set pll3 to 297 MHz */
335 	clock_set_pll3(297000000);
336 
337 	/* Set hdmi parent to pll3 */
338 	clrsetbits_le32(&ccm->hdmi_clk_cfg, CCM_HDMI_CTRL_PLL_MASK,
339 			CCM_HDMI_CTRL_PLL3);
340 
341 	/* Set ahb gating to pass */
342 	setbits_le32(&ccm->ahb_reset1_cfg, 1 << AHB_RESET_OFFSET_HDMI);
343 	setbits_le32(&ccm->ahb_reset1_cfg, 1 << AHB_RESET_OFFSET_HDMI2);
344 	setbits_le32(&ccm->ahb_gate1, 1 << AHB_GATE_OFFSET_HDMI);
345 	setbits_le32(&ccm->hdmi_slow_clk_cfg, CCM_HDMI_SLOW_CTRL_DDC_GATE);
346 
347 	/* Clock on */
348 	setbits_le32(&ccm->hdmi_clk_cfg, CCM_HDMI_CTRL_GATE);
349 
350 	sunxi_dw_hdmi_phy_init();
351 
352 	ret = sunxi_dw_hdmi_wait_for_hpd();
353 	if (ret < 0) {
354 		debug("hdmi can not get hpd signal\n");
355 		return -1;
356 	}
357 
358 	priv->hdmi.ioaddr = SUNXI_HDMI_BASE;
359 	priv->hdmi.i2c_clk_high = 0xd8;
360 	priv->hdmi.i2c_clk_low = 0xfe;
361 	priv->hdmi.reg_io_width = 1;
362 	priv->hdmi.phy_set = sunxi_dw_hdmi_phy_cfg;
363 	priv->mux = uc_plat->source_id;
364 
365 	dw_hdmi_init(&priv->hdmi);
366 
367 	return 0;
368 }
369 
370 static const struct dm_display_ops sunxi_dw_hdmi_ops = {
371 	.read_edid = sunxi_dw_hdmi_read_edid,
372 	.enable = sunxi_dw_hdmi_enable,
373 };
374 
375 U_BOOT_DRIVER(sunxi_dw_hdmi) = {
376 	.name	= "sunxi_dw_hdmi",
377 	.id	= UCLASS_DISPLAY,
378 	.ops	= &sunxi_dw_hdmi_ops,
379 	.probe	= sunxi_dw_hdmi_probe,
380 	.priv_auto_alloc_size = sizeof(struct sunxi_dw_hdmi_priv),
381 };
382 
383 U_BOOT_DEVICE(sunxi_dw_hdmi) = {
384 	.name = "sunxi_dw_hdmi"
385 };
386