2 * Novena video output support
4 * IT6251 code based on code Copyright (C) 2014 Sean Cross
5 * from https://github.com/xobs/novena-linux.git commit
6 * 3d85836ee1377d445531928361809612aa0a18db
8 * Copyright (C) 2014 Marek Vasut <marex@denx.de>
10 * SPDX-License-Identifier: GPL-2.0+
14 #include <asm/errno.h>
17 #include <asm/arch/clock.h>
18 #include <asm/arch/crm_regs.h>
19 #include <asm/arch/imx-regs.h>
20 #include <asm/arch/iomux.h>
21 #include <asm/arch/mxc_hdmi.h>
22 #include <asm/arch/sys_proto.h>
23 #include <asm/imx-common/iomux-v3.h>
24 #include <asm/imx-common/mxc_i2c.h>
25 #include <asm/imx-common/video.h>
28 #include <ipu_pixfmt.h>
30 #include <linux/input.h>
32 #include <stdio_dev.h>
36 #define IT6251_VENDOR_ID_LOW 0x00
37 #define IT6251_VENDOR_ID_HIGH 0x01
38 #define IT6251_DEVICE_ID_LOW 0x02
39 #define IT6251_DEVICE_ID_HIGH 0x03
40 #define IT6251_SYSTEM_STATUS 0x0d
41 #define IT6251_SYSTEM_STATUS_RINTSTATUS (1 << 0)
42 #define IT6251_SYSTEM_STATUS_RHPDSTATUS (1 << 1)
43 #define IT6251_SYSTEM_STATUS_RVIDEOSTABLE (1 << 2)
44 #define IT6251_SYSTEM_STATUS_RPLL_IOLOCK (1 << 3)
45 #define IT6251_SYSTEM_STATUS_RPLL_XPLOCK (1 << 4)
46 #define IT6251_SYSTEM_STATUS_RPLL_SPLOCK (1 << 5)
47 #define IT6251_SYSTEM_STATUS_RAUXFREQ_LOCK (1 << 6)
48 #define IT6251_REF_STATE 0x0e
49 #define IT6251_REF_STATE_MAIN_LINK_DISABLED (1 << 0)
50 #define IT6251_REF_STATE_AUX_CHANNEL_READ (1 << 1)
51 #define IT6251_REF_STATE_CR_PATTERN (1 << 2)
52 #define IT6251_REF_STATE_EQ_PATTERN (1 << 3)
53 #define IT6251_REF_STATE_NORMAL_OPERATION (1 << 4)
54 #define IT6251_REF_STATE_MUTED (1 << 5)
56 #define IT6251_REG_PCLK_CNT_LOW 0x57
57 #define IT6251_REG_PCLK_CNT_HIGH 0x58
59 #define IT6521_RETRY_MAX 20
61 static int it6251_is_stable(void)
63 const unsigned int caddr = NOVENA_IT6251_CHIPADDR;
64 const unsigned int laddr = NOVENA_IT6251_LVDSADDR;
70 rpclkcnt = (i2c_reg_read(caddr, 0x13) & 0xff) |
71 ((i2c_reg_read(caddr, 0x14) << 8) & 0x0f00);
72 debug("RPCLKCnt: %d\n", rpclkcnt);
74 status = i2c_reg_read(caddr, IT6251_SYSTEM_STATUS);
75 debug("System status: 0x%02x\n", status);
77 clkcnt = (i2c_reg_read(laddr, IT6251_REG_PCLK_CNT_LOW) & 0xff) |
78 ((i2c_reg_read(laddr, IT6251_REG_PCLK_CNT_HIGH) << 8) &
80 debug("Clock: 0x%02x\n", clkcnt);
82 refstate = i2c_reg_read(laddr, IT6251_REF_STATE);
83 debug("Ref Link State: 0x%02x\n", refstate);
85 if ((refstate & 0x1f) != 0)
88 /* If video is muted, that's a failure */
89 if (refstate & IT6251_REF_STATE_MUTED)
92 if (!(status & IT6251_SYSTEM_STATUS_RVIDEOSTABLE))
98 static int it6251_ready(void)
100 const unsigned int caddr = NOVENA_IT6251_CHIPADDR;
102 /* Test if the IT6251 came out of reset by reading ID regs. */
103 if (i2c_reg_read(caddr, IT6251_VENDOR_ID_LOW) != 0x15)
105 if (i2c_reg_read(caddr, IT6251_VENDOR_ID_HIGH) != 0xca)
107 if (i2c_reg_read(caddr, IT6251_DEVICE_ID_LOW) != 0x51)
109 if (i2c_reg_read(caddr, IT6251_DEVICE_ID_HIGH) != 0x62)
115 static void it6251_program_regs(void)
117 const unsigned int caddr = NOVENA_IT6251_CHIPADDR;
118 const unsigned int laddr = NOVENA_IT6251_LVDSADDR;
120 i2c_reg_write(caddr, 0x05, 0x00);
123 /* set LVDSRX address, and enable */
124 i2c_reg_write(caddr, 0xfd, 0xbc);
125 i2c_reg_write(caddr, 0xfe, 0x01);
130 /* This write always fails, because the chip goes into reset */
132 i2c_reg_write(laddr, 0x05, 0xff);
133 i2c_reg_write(laddr, 0x05, 0x00);
135 /* reset LVDSRX PLL */
136 i2c_reg_write(laddr, 0x3b, 0x42);
137 i2c_reg_write(laddr, 0x3b, 0x43);
139 /* something with SSC PLL */
140 i2c_reg_write(laddr, 0x3c, 0x08);
141 /* don't swap links, but writing reserved registers */
142 i2c_reg_write(laddr, 0x0b, 0x88);
144 /* JEIDA, 8-bit depth 0x11, orig 0x42 */
145 i2c_reg_write(laddr, 0x2c, 0x01);
147 i2c_reg_write(laddr, 0x32, 0x04);
149 i2c_reg_write(laddr, 0x35, 0xe0);
150 /* "reserved" + clock delay */
151 i2c_reg_write(laddr, 0x2b, 0x24);
153 /* reset LVDSRX pix clock */
154 i2c_reg_write(laddr, 0x05, 0x02);
155 i2c_reg_write(laddr, 0x05, 0x00);
160 /* set for two lane mode, normal op, no swapping, no downspread */
161 i2c_reg_write(caddr, 0x16, 0x02);
163 /* some AUX channel EDID magic */
164 i2c_reg_write(caddr, 0x23, 0x40);
166 /* power down lanes 3-0 */
167 i2c_reg_write(caddr, 0x5c, 0xf3);
169 /* enable DP scrambling, change EQ CR phase */
170 i2c_reg_write(caddr, 0x5f, 0x06);
172 /* color mode RGB, pclk/2 */
173 i2c_reg_write(caddr, 0x60, 0x02);
174 /* dual pixel input mode, no EO swap, no RGB swap */
175 i2c_reg_write(caddr, 0x61, 0x04);
176 /* M444B24 video format */
177 i2c_reg_write(caddr, 0x62, 0x01);
179 /* vesa range / not interlace / vsync high / hsync high */
180 i2c_reg_write(caddr, 0xa0, 0x0F);
182 /* hpd event timer set to 1.6-ish ms */
183 i2c_reg_write(caddr, 0xc9, 0xf5);
185 /* more reserved magic */
186 i2c_reg_write(caddr, 0xca, 0x4d);
187 i2c_reg_write(caddr, 0xcb, 0x37);
189 /* enhanced framing mode, auto video fifo reset, video mute disable */
190 i2c_reg_write(caddr, 0xd3, 0x03);
192 /* "vidstmp" and some reserved stuff */
193 i2c_reg_write(caddr, 0xd4, 0x45);
195 /* queue number -- reserved */
196 i2c_reg_write(caddr, 0xe7, 0xa0);
197 /* info frame packets and reserved */
198 i2c_reg_write(caddr, 0xe8, 0x33);
200 i2c_reg_write(caddr, 0xec, 0x00);
202 /* select PC master reg for aux channel? */
203 i2c_reg_write(caddr, 0x23, 0x42);
205 /* send PC request commands */
206 i2c_reg_write(caddr, 0x24, 0x00);
207 i2c_reg_write(caddr, 0x25, 0x00);
208 i2c_reg_write(caddr, 0x26, 0x00);
210 /* native aux read */
211 i2c_reg_write(caddr, 0x2b, 0x00);
212 /* back to internal */
213 i2c_reg_write(caddr, 0x23, 0x40);
215 /* voltage swing level 3 */
216 i2c_reg_write(caddr, 0x19, 0xff);
217 /* pre-emphasis level 3 */
218 i2c_reg_write(caddr, 0x1a, 0xff);
220 /* start link training */
221 i2c_reg_write(caddr, 0x17, 0x01);
224 static int it6251_init(void)
226 const unsigned int caddr = NOVENA_IT6251_CHIPADDR;
228 int tries, retries = 0;
230 for (retries = 0; retries < IT6521_RETRY_MAX; retries++) {
231 /* Program the chip. */
232 it6251_program_regs();
234 /* Wait for video stable. */
235 for (tries = 0; tries < 100; tries++) {
236 reg = i2c_reg_read(caddr, 0x17);
237 /* Test Link CFG, STS, LCS read done. */
238 if ((reg & 0xe0) != 0xe0) {
239 /* Not yet, wait a bit more. */
244 /* Test if the video input is stable. */
245 if (it6251_is_stable())
249 * If we couldn't stabilize, requeue and try again,
250 * because it means that the LVDS channel isn't
253 printf("Display didn't stabilize.\n");
254 printf("This may be because the LVDS port is still in powersave mode.\n");
261 static void enable_hdmi(struct display_info_t const *dev)
263 imx_enable_hdmi_phy();
266 static int lvds_enabled;
268 static void enable_lvds(struct display_info_t const *dev)
273 /* ITE IT6251 power enable. */
274 gpio_direction_output(NOVENA_ITE6251_PWR_GPIO, 0);
276 gpio_direction_output(NOVENA_ITE6251_PWR_GPIO, 1);
281 static int detect_lvds(struct display_info_t const *dev)
283 int ret, loops = 250;
287 ret = i2c_set_bus_num(NOVENA_IT6251_I2C_BUS);
289 puts("Cannot select IT6251 I2C bus.\n");
293 /* Wait up-to ~250 mS for the LVDS to come up. */
295 ret = it6251_ready();
305 struct display_info_t const displays[] = {
310 .pixfmt = IPU_PIX_FMT_RGB24,
311 .detect = detect_hdmi,
312 .enable = enable_hdmi,
326 .vmode = FB_VMODE_NONINTERLACED
329 /* LVDS Output: N133HSE-EA1 Rev. C1 */
331 .pixfmt = IPU_PIX_FMT_RGB24,
332 .detect = detect_lvds,
333 .enable = enable_lvds,
335 .name = "Chimei-FHD",
346 .sync = FB_SYNC_HOR_HIGH_ACT |
347 FB_SYNC_VERT_HIGH_ACT |
349 .vmode = FB_VMODE_NONINTERLACED,
354 size_t display_count = ARRAY_SIZE(displays);
356 static void enable_vpll(void)
358 struct mxc_ccm_reg *ccm = (struct mxc_ccm_reg *)CCM_BASE_ADDR;
359 int timeout = 100000;
361 setbits_le32(&ccm->analog_pll_video, BM_ANADIG_PLL_VIDEO_POWERDOWN);
363 clrsetbits_le32(&ccm->analog_pll_video,
364 BM_ANADIG_PLL_VIDEO_DIV_SELECT |
365 BM_ANADIG_PLL_VIDEO_POST_DIV_SELECT,
366 BF_ANADIG_PLL_VIDEO_DIV_SELECT(37) |
367 BF_ANADIG_PLL_VIDEO_POST_DIV_SELECT(1));
369 writel(BF_ANADIG_PLL_VIDEO_NUM_A(11), &ccm->analog_pll_video_num);
370 writel(BF_ANADIG_PLL_VIDEO_DENOM_B(12), &ccm->analog_pll_video_denom);
372 clrbits_le32(&ccm->analog_pll_video, BM_ANADIG_PLL_VIDEO_POWERDOWN);
375 if (readl(&ccm->analog_pll_video) & BM_ANADIG_PLL_VIDEO_LOCK)
378 printf("Warning: video pll lock timeout!\n");
380 clrsetbits_le32(&ccm->analog_pll_video,
381 BM_ANADIG_PLL_VIDEO_BYPASS,
382 BM_ANADIG_PLL_VIDEO_ENABLE);
385 void setup_display_clock(void)
387 struct mxc_ccm_reg *mxc_ccm = (struct mxc_ccm_reg *)CCM_BASE_ADDR;
388 struct iomuxc *iomux = (struct iomuxc *)IOMUXC_BASE_ADDR;
394 /* Turn on IPU LDB DI0 clocks */
395 setbits_le32(&mxc_ccm->CCGR3, MXC_CCM_CCGR3_LDB_DI0_MASK);
397 /* Switch LDB DI0 to PLL5 (Video PLL) */
398 clrsetbits_le32(&mxc_ccm->cs2cdr,
399 MXC_CCM_CS2CDR_LDB_DI0_CLK_SEL_MASK,
400 (0 << MXC_CCM_CS2CDR_LDB_DI0_CLK_SEL_OFFSET));
402 /* LDB clock div by 3.5 */
403 clrbits_le32(&mxc_ccm->cscmr2, MXC_CCM_CSCMR2_LDB_DI0_IPU_DIV);
405 /* DI0 clock derived from ldb_di0_clk */
406 clrsetbits_le32(&mxc_ccm->chsccdr,
407 MXC_CCM_CHSCCDR_IPU1_DI0_CLK_SEL_MASK,
408 (CHSCCDR_CLK_SEL_LDB_DI0 <<
409 MXC_CCM_CHSCCDR_IPU1_DI0_CLK_SEL_OFFSET)
412 /* Enable both LVDS channels, both connected to DI0. */
413 writel(IOMUXC_GPR2_DI0_VS_POLARITY_ACTIVE_HIGH |
414 IOMUXC_GPR2_BIT_MAPPING_CH1_JEIDA |
415 IOMUXC_GPR2_DATA_WIDTH_CH1_24BIT |
416 IOMUXC_GPR2_BIT_MAPPING_CH0_JEIDA |
417 IOMUXC_GPR2_DATA_WIDTH_CH0_24BIT |
418 IOMUXC_GPR2_SPLIT_MODE_EN_MASK |
419 IOMUXC_GPR2_LVDS_CH1_MODE_ENABLED_DI0 |
420 IOMUXC_GPR2_LVDS_CH0_MODE_ENABLED_DI0,
423 clrsetbits_le32(&iomux->gpr[3],
424 IOMUXC_GPR3_LVDS0_MUX_CTL_MASK |
425 IOMUXC_GPR3_LVDS1_MUX_CTL_MASK,
426 (IOMUXC_GPR3_MUX_SRC_IPU1_DI0 <<
427 IOMUXC_GPR3_LVDS0_MUX_CTL_OFFSET) |
428 (IOMUXC_GPR3_MUX_SRC_IPU1_DI0 <<
429 IOMUXC_GPR3_LVDS1_MUX_CTL_OFFSET)
433 void setup_display_lvds(void)
437 ret = i2c_set_bus_num(NOVENA_IT6251_I2C_BUS);
439 puts("Cannot select LVDS-to-eDP I2C bus.\n");
443 /* The IT6251 should be ready now, if it's not, it's not connected. */
444 ret = it6251_ready();
448 /* Init the LVDS-to-eDP chip and if it succeeded, enable backlight. */
451 /* Backlight power enable. */
452 gpio_direction_output(NOVENA_BACKLIGHT_PWR_GPIO, 1);
453 /* PWM backlight pin, always on for full brightness. */
454 gpio_direction_output(NOVENA_BACKLIGHT_PWM_GPIO, 1);