1 // SPDX-License-Identifier: GPL-2.0+
3 * Novena video output support
5 * IT6251 code based on code Copyright (C) 2014 Sean Cross
6 * from https://github.com/xobs/novena-linux.git commit
7 * 3d85836ee1377d445531928361809612aa0a18db
9 * Copyright (C) 2014 Marek Vasut <marex@denx.de>
13 #include <linux/errno.h>
16 #include <asm/arch/clock.h>
17 #include <asm/arch/crm_regs.h>
18 #include <asm/arch/imx-regs.h>
19 #include <asm/arch/iomux.h>
20 #include <asm/arch/mxc_hdmi.h>
21 #include <asm/arch/sys_proto.h>
22 #include <asm/mach-imx/iomux-v3.h>
23 #include <asm/mach-imx/mxc_i2c.h>
24 #include <asm/mach-imx/video.h>
27 #include <ipu_pixfmt.h>
29 #include <linux/input.h>
31 #include <stdio_dev.h>
35 #define IT6251_VENDOR_ID_LOW 0x00
36 #define IT6251_VENDOR_ID_HIGH 0x01
37 #define IT6251_DEVICE_ID_LOW 0x02
38 #define IT6251_DEVICE_ID_HIGH 0x03
39 #define IT6251_SYSTEM_STATUS 0x0d
40 #define IT6251_SYSTEM_STATUS_RINTSTATUS (1 << 0)
41 #define IT6251_SYSTEM_STATUS_RHPDSTATUS (1 << 1)
42 #define IT6251_SYSTEM_STATUS_RVIDEOSTABLE (1 << 2)
43 #define IT6251_SYSTEM_STATUS_RPLL_IOLOCK (1 << 3)
44 #define IT6251_SYSTEM_STATUS_RPLL_XPLOCK (1 << 4)
45 #define IT6251_SYSTEM_STATUS_RPLL_SPLOCK (1 << 5)
46 #define IT6251_SYSTEM_STATUS_RAUXFREQ_LOCK (1 << 6)
47 #define IT6251_REF_STATE 0x0e
48 #define IT6251_REF_STATE_MAIN_LINK_DISABLED (1 << 0)
49 #define IT6251_REF_STATE_AUX_CHANNEL_READ (1 << 1)
50 #define IT6251_REF_STATE_CR_PATTERN (1 << 2)
51 #define IT6251_REF_STATE_EQ_PATTERN (1 << 3)
52 #define IT6251_REF_STATE_NORMAL_OPERATION (1 << 4)
53 #define IT6251_REF_STATE_MUTED (1 << 5)
55 #define IT6251_REG_PCLK_CNT_LOW 0x57
56 #define IT6251_REG_PCLK_CNT_HIGH 0x58
58 #define IT6521_RETRY_MAX 20
60 static int it6251_is_stable(void)
62 const unsigned int caddr = NOVENA_IT6251_CHIPADDR;
63 const unsigned int laddr = NOVENA_IT6251_LVDSADDR;
69 rpclkcnt = (i2c_reg_read(caddr, 0x13) & 0xff) |
70 ((i2c_reg_read(caddr, 0x14) << 8) & 0x0f00);
71 debug("RPCLKCnt: %d\n", rpclkcnt);
73 status = i2c_reg_read(caddr, IT6251_SYSTEM_STATUS);
74 debug("System status: 0x%02x\n", status);
76 clkcnt = (i2c_reg_read(laddr, IT6251_REG_PCLK_CNT_LOW) & 0xff) |
77 ((i2c_reg_read(laddr, IT6251_REG_PCLK_CNT_HIGH) << 8) &
79 debug("Clock: 0x%02x\n", clkcnt);
81 refstate = i2c_reg_read(laddr, IT6251_REF_STATE);
82 debug("Ref Link State: 0x%02x\n", refstate);
84 if ((refstate & 0x1f) != 0)
87 /* If video is muted, that's a failure */
88 if (refstate & IT6251_REF_STATE_MUTED)
91 if (!(status & IT6251_SYSTEM_STATUS_RVIDEOSTABLE))
97 static int it6251_ready(void)
99 const unsigned int caddr = NOVENA_IT6251_CHIPADDR;
101 /* Test if the IT6251 came out of reset by reading ID regs. */
102 if (i2c_reg_read(caddr, IT6251_VENDOR_ID_LOW) != 0x15)
104 if (i2c_reg_read(caddr, IT6251_VENDOR_ID_HIGH) != 0xca)
106 if (i2c_reg_read(caddr, IT6251_DEVICE_ID_LOW) != 0x51)
108 if (i2c_reg_read(caddr, IT6251_DEVICE_ID_HIGH) != 0x62)
114 static void it6251_program_regs(void)
116 const unsigned int caddr = NOVENA_IT6251_CHIPADDR;
117 const unsigned int laddr = NOVENA_IT6251_LVDSADDR;
119 i2c_reg_write(caddr, 0x05, 0x00);
122 /* set LVDSRX address, and enable */
123 i2c_reg_write(caddr, 0xfd, 0xbc);
124 i2c_reg_write(caddr, 0xfe, 0x01);
129 /* This write always fails, because the chip goes into reset */
131 i2c_reg_write(laddr, 0x05, 0xff);
132 i2c_reg_write(laddr, 0x05, 0x00);
134 /* reset LVDSRX PLL */
135 i2c_reg_write(laddr, 0x3b, 0x42);
136 i2c_reg_write(laddr, 0x3b, 0x43);
138 /* something with SSC PLL */
139 i2c_reg_write(laddr, 0x3c, 0x08);
140 /* don't swap links, but writing reserved registers */
141 i2c_reg_write(laddr, 0x0b, 0x88);
143 /* JEIDA, 8-bit depth 0x11, orig 0x42 */
144 i2c_reg_write(laddr, 0x2c, 0x01);
146 i2c_reg_write(laddr, 0x32, 0x04);
148 i2c_reg_write(laddr, 0x35, 0xe0);
149 /* "reserved" + clock delay */
150 i2c_reg_write(laddr, 0x2b, 0x24);
152 /* reset LVDSRX pix clock */
153 i2c_reg_write(laddr, 0x05, 0x02);
154 i2c_reg_write(laddr, 0x05, 0x00);
159 /* set for two lane mode, normal op, no swapping, no downspread */
160 i2c_reg_write(caddr, 0x16, 0x02);
162 /* some AUX channel EDID magic */
163 i2c_reg_write(caddr, 0x23, 0x40);
165 /* power down lanes 3-0 */
166 i2c_reg_write(caddr, 0x5c, 0xf3);
168 /* enable DP scrambling, change EQ CR phase */
169 i2c_reg_write(caddr, 0x5f, 0x06);
171 /* color mode RGB, pclk/2 */
172 i2c_reg_write(caddr, 0x60, 0x02);
173 /* dual pixel input mode, no EO swap, no RGB swap */
174 i2c_reg_write(caddr, 0x61, 0x04);
175 /* M444B24 video format */
176 i2c_reg_write(caddr, 0x62, 0x01);
178 /* vesa range / not interlace / vsync high / hsync high */
179 i2c_reg_write(caddr, 0xa0, 0x0F);
181 /* hpd event timer set to 1.6-ish ms */
182 i2c_reg_write(caddr, 0xc9, 0xf5);
184 /* more reserved magic */
185 i2c_reg_write(caddr, 0xca, 0x4d);
186 i2c_reg_write(caddr, 0xcb, 0x37);
188 /* enhanced framing mode, auto video fifo reset, video mute disable */
189 i2c_reg_write(caddr, 0xd3, 0x03);
191 /* "vidstmp" and some reserved stuff */
192 i2c_reg_write(caddr, 0xd4, 0x45);
194 /* queue number -- reserved */
195 i2c_reg_write(caddr, 0xe7, 0xa0);
196 /* info frame packets and reserved */
197 i2c_reg_write(caddr, 0xe8, 0x33);
199 i2c_reg_write(caddr, 0xec, 0x00);
201 /* select PC master reg for aux channel? */
202 i2c_reg_write(caddr, 0x23, 0x42);
204 /* send PC request commands */
205 i2c_reg_write(caddr, 0x24, 0x00);
206 i2c_reg_write(caddr, 0x25, 0x00);
207 i2c_reg_write(caddr, 0x26, 0x00);
209 /* native aux read */
210 i2c_reg_write(caddr, 0x2b, 0x00);
211 /* back to internal */
212 i2c_reg_write(caddr, 0x23, 0x40);
214 /* voltage swing level 3 */
215 i2c_reg_write(caddr, 0x19, 0xff);
216 /* pre-emphasis level 3 */
217 i2c_reg_write(caddr, 0x1a, 0xff);
219 /* start link training */
220 i2c_reg_write(caddr, 0x17, 0x01);
223 static int it6251_init(void)
225 const unsigned int caddr = NOVENA_IT6251_CHIPADDR;
227 int tries, retries = 0;
229 for (retries = 0; retries < IT6521_RETRY_MAX; retries++) {
230 /* Program the chip. */
231 it6251_program_regs();
233 /* Wait for video stable. */
234 for (tries = 0; tries < 100; tries++) {
235 reg = i2c_reg_read(caddr, 0x17);
236 /* Test Link CFG, STS, LCS read done. */
237 if ((reg & 0xe0) != 0xe0) {
238 /* Not yet, wait a bit more. */
243 /* Test if the video input is stable. */
244 if (it6251_is_stable())
248 * If we couldn't stabilize, requeue and try again,
249 * because it means that the LVDS channel isn't
252 printf("Display didn't stabilize.\n");
253 printf("This may be because the LVDS port is still in powersave mode.\n");
260 static void enable_hdmi(struct display_info_t const *dev)
262 imx_enable_hdmi_phy();
265 static int lvds_enabled;
267 static void enable_lvds(struct display_info_t const *dev)
272 /* ITE IT6251 power enable. */
273 gpio_request(NOVENA_ITE6251_PWR_GPIO, "ite6251-power");
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 gpio_request(NOVENA_BACKLIGHT_PWR_GPIO, "backlight-power");
452 gpio_request(NOVENA_BACKLIGHT_PWM_GPIO, "backlight-pwm");
453 /* Backlight power enable. */
454 gpio_direction_output(NOVENA_BACKLIGHT_PWR_GPIO, 1);
455 /* PWM backlight pin, always on for full brightness. */
456 gpio_direction_output(NOVENA_BACKLIGHT_PWM_GPIO, 1);