/* SPDX-License-Identifier: GPL-2.0-only */

#include <assert.h>
#include <console/console.h>
#include <device/mmio.h>
#include <delay.h>
#include <edid.h>
#include <soc/dsi.h>
#include <string.h>
#include <timer.h>

#define MIN_HFP_BYTE	2
#define MIN_HBP_BYTE	2

static unsigned int mtk_dsi_get_bits_per_pixel(u32 format)
{
	switch (format) {
	case MIPI_DSI_FMT_RGB565:
		return 16;
	case MIPI_DSI_FMT_RGB666_PACKED:
		return 18;
	case MIPI_DSI_FMT_RGB666:
	case MIPI_DSI_FMT_RGB888:
		return 24;
	}
	printk(BIOS_WARNING, "%s: WARN: Unknown format %d, assuming 24 bpp\n",
	       __func__, format);
	return 24;
}

static u32 mtk_dsi_get_data_rate(u32 bits_per_pixel, u32 lanes,
				 const struct edid *edid)
{
	/* data_rate = pixel_clock * bits_per_pixel * mipi_ratio / lanes
	 * Note pixel_clock comes in kHz and returned data_rate is in bps.
	 * mipi_ratio is the clk coefficient to balance the pixel clk in MIPI
	 * for older platforms which do not have complete implementation in HFP.
	 * Newer platforms should just set that to 1.0 (100 / 100).
	 */
	u32 data_rate = DIV_ROUND_UP((u64)edid->mode.pixel_clock *
				     bits_per_pixel * 1000 *
				     MTK_DSI_MIPI_RATIO_NUMERATOR,
				     (u64)lanes *
				     MTK_DSI_MIPI_RATIO_DENOMINATOR);
	printk(BIOS_INFO, "DSI data_rate: %u bps\n", data_rate);

	if (data_rate < MTK_DSI_DATA_RATE_MIN_MHZ * MHz) {
		printk(BIOS_ERR, "data rate (%ubps) must be >= %ubps. "
		       "Please check the pixel clock (%u), "
		       "bits per pixel (%u), "
		       "mipi_ratio (%d%%) and number of lanes (%d)\n",
		       data_rate, MTK_DSI_DATA_RATE_MIN_MHZ * MHz,
		       edid->mode.pixel_clock, bits_per_pixel,
		       (100 * MTK_DSI_MIPI_RATIO_NUMERATOR /
			MTK_DSI_MIPI_RATIO_DENOMINATOR), lanes);
		return 0;
	}
	return data_rate;
}

__weak void mtk_dsi_override_phy_timing(struct mtk_phy_timing *timing)
{
	/* Do nothing. */
}

static void mtk_dsi_phy_timing(u32 data_rate, struct mtk_phy_timing *timing)
{
	u32 timcon0, timcon1, timcon2, timcon3;
	u32 data_rate_mhz = DIV_ROUND_UP(data_rate, MHz);

	memset(timing, 0, sizeof(*timing));

	timing->lpx = (60 * data_rate_mhz / (8 * 1000)) + 1;
	timing->da_hs_prepare = (80 * data_rate_mhz + 4 * 1000) / 8000;
	timing->da_hs_zero = (170 * data_rate_mhz + 10 * 1000) / 8000 + 1 -
			     timing->da_hs_prepare;
	timing->da_hs_trail = timing->da_hs_prepare + 1;

	timing->ta_go = 4 * timing->lpx - 2;
	timing->ta_sure = timing->lpx + 2;
	timing->ta_get = 4 * timing->lpx;
	timing->da_hs_exit = 2 * timing->lpx + 1;

	timing->da_hs_sync = 1;

	timing->clk_hs_prepare = 70 * data_rate_mhz / (8 * 1000);
	timing->clk_hs_post = timing->clk_hs_prepare + 8;
	timing->clk_hs_trail = timing->clk_hs_prepare;
	timing->clk_hs_zero = timing->clk_hs_trail * 4;
	timing->clk_hs_exit = 2 * timing->clk_hs_trail;

	/* Allow board-specific tuning. */
	mtk_dsi_override_phy_timing(timing);

	timcon0 = timing->lpx | timing->da_hs_prepare << 8 |
		  timing->da_hs_zero << 16 | timing->da_hs_trail << 24;
	timcon1 = timing->ta_go | timing->ta_sure << 8 |
		  timing->ta_get << 16 | timing->da_hs_exit << 24;
	timcon2 = timing->da_hs_sync << 8 | timing->clk_hs_zero << 16 |
		  timing->clk_hs_trail << 24;
	timcon3 = timing->clk_hs_prepare | timing->clk_hs_post << 8 |
		  timing->clk_hs_exit << 16;

	write32(&dsi0->dsi_phy_timecon0, timcon0);
	write32(&dsi0->dsi_phy_timecon1, timcon1);
	write32(&dsi0->dsi_phy_timecon2, timcon2);
	write32(&dsi0->dsi_phy_timecon3, timcon3);
}

static void mtk_dsi_clk_hs_mode_enable(void)
{
	setbits32(&dsi0->dsi_phy_lccon, LC_HS_TX_EN);
}

static void mtk_dsi_clk_hs_mode_disable(void)
{
	clrbits32(&dsi0->dsi_phy_lccon, LC_HS_TX_EN);
}

static void mtk_dsi_set_mode(u32 mode_flags)
{
	u32 tmp_reg1 = 0;

	if (mode_flags & MIPI_DSI_MODE_VIDEO) {
		tmp_reg1 = SYNC_PULSE_MODE;

		if (mode_flags & MIPI_DSI_MODE_VIDEO_BURST)
			tmp_reg1 = BURST_MODE;

		if (mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE)
			tmp_reg1 = SYNC_PULSE_MODE;
	}

	write32(&dsi0->dsi_mode_ctrl, tmp_reg1);
}

static void mtk_dsi_rxtx_control(u32 mode_flags, u32 lanes)
{
	u32 tmp_reg = 0;

	switch (lanes) {
	case 1:
		tmp_reg = 1 << 2;
		break;
	case 2:
		tmp_reg = 3 << 2;
		break;
	case 3:
		tmp_reg = 7 << 2;
		break;
	case 4:
	default:
		tmp_reg = 0xf << 2;
		break;
	}

	if (mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS)
		tmp_reg |= NON_CONTINUOUS_CLK;

	if (!(mode_flags & MIPI_DSI_MODE_EOT_PACKET))
		tmp_reg |= EOTP_DISABLE;

	write32(&dsi0->dsi_txrx_ctrl, tmp_reg);
}

static void mtk_dsi_config_vdo_timing(u32 mode_flags, u32 format, u32 lanes,
				      const struct edid *edid,
				      const struct mtk_phy_timing *phy_timing)
{
	u32 hsync_active_byte;
	u32 hbp;
	u32 hfp;
	s32 hbp_byte;
	s32 hfp_byte;
	u32 vbp_byte;
	u32 vfp_byte;
	u32 bytes_per_pixel;
	u32 packet_fmt;
	u32 hactive;
	u32 data_phy_cycles;

	bytes_per_pixel = DIV_ROUND_UP(mtk_dsi_get_bits_per_pixel(format), 8);
	vbp_byte = edid->mode.vbl - edid->mode.vso - edid->mode.vspw -
		   edid->mode.vborder;
	vfp_byte = edid->mode.vso - edid->mode.vborder;

	write32(&dsi0->dsi_vsa_nl, edid->mode.vspw);
	write32(&dsi0->dsi_vbp_nl, vbp_byte);
	write32(&dsi0->dsi_vfp_nl, vfp_byte);
	write32(&dsi0->dsi_vact_nl, edid->mode.va);

	hsync_active_byte = edid->mode.hspw * bytes_per_pixel - 10;

	hbp = edid->mode.hbl - edid->mode.hso - edid->mode.hspw -
	      edid->mode.hborder;
	hfp = edid->mode.hso - edid->mode.hborder;

	if (mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE)
		hbp_byte = hbp * bytes_per_pixel - 10;
	else
		hbp_byte = (hbp + edid->mode.hspw) * bytes_per_pixel - 10;
	hfp_byte = hfp * bytes_per_pixel;

	data_phy_cycles = phy_timing->lpx + phy_timing->da_hs_prepare +
			  phy_timing->da_hs_zero + phy_timing->da_hs_exit + 3;

	u32 delta = 12;

	if (mode_flags & MIPI_DSI_MODE_EOT_PACKET)
		delta += 2;

	if (mode_flags & MIPI_DSI_MODE_VIDEO_BURST)
		delta += 6;

	u32 d_phy = phy_timing->d_phy;
	if (d_phy == 0)
		d_phy = data_phy_cycles * lanes + delta;

	if ((hfp + hbp) * bytes_per_pixel > d_phy) {
		hfp_byte -= d_phy * hfp / (hfp + hbp);
		hbp_byte -= d_phy * hbp / (hfp + hbp);
	} else {
		printk(BIOS_ERR, "HFP plus HBP is not greater than d_phy, "
		       "the panel may not work properly.\n");
	}

	if (mode_flags & MIPI_DSI_MODE_LINE_END) {
		hsync_active_byte = DIV_ROUND_UP(hsync_active_byte, lanes) * lanes - 2;
		hbp_byte = DIV_ROUND_UP(hbp_byte, lanes) * lanes - 2;
		hfp_byte = DIV_ROUND_UP(hfp_byte, lanes) * lanes - 2;
		hbp_byte -= (edid->mode.ha * bytes_per_pixel + 2) % lanes;
	}

	if (hfp_byte + hbp_byte < MIN_HFP_BYTE + MIN_HBP_BYTE) {
		printk(BIOS_ERR, "Calculated hfp_byte and hbp_byte are too small, "
		       "the panel may not work properly.\n");
	} else if (hfp_byte < MIN_HFP_BYTE) {
		printk(BIOS_NOTICE, "Calculated hfp_byte is too small, "
		       "adjust it to the minimum value.\n");
		hbp_byte -= MIN_HFP_BYTE - hfp_byte;
		hfp_byte = MIN_HFP_BYTE;
	} else if (hbp_byte < MIN_HBP_BYTE) {
		printk(BIOS_NOTICE, "Calculated hbp_byte is too small, "
		       "adjust it to the minimum value.\n");
		hfp_byte -= MIN_HBP_BYTE - hbp_byte;
		hbp_byte = MIN_HBP_BYTE;
	}

	write32(&dsi0->dsi_hsa_wc, hsync_active_byte);
	write32(&dsi0->dsi_hbp_wc, hbp_byte);
	write32(&dsi0->dsi_hfp_wc, hfp_byte);

	switch (format) {
	case MIPI_DSI_FMT_RGB888:
		packet_fmt = PACKED_PS_24BIT_RGB888;
		break;
	case MIPI_DSI_FMT_RGB666:
		packet_fmt = LOOSELY_PS_18BIT_RGB666;
		break;
	case MIPI_DSI_FMT_RGB666_PACKED:
		packet_fmt = PACKED_PS_18BIT_RGB666;
		break;
	case MIPI_DSI_FMT_RGB565:
		packet_fmt = PACKED_PS_16BIT_RGB565;
		break;
	default:
		packet_fmt = PACKED_PS_24BIT_RGB888;
		break;
	}

	hactive = edid->mode.ha;
	packet_fmt |= (hactive * bytes_per_pixel) & DSI_PS_WC;

	write32(&dsi0->dsi_psctrl,
		PIXEL_STREAM_CUSTOM_HEADER << DSI_PSCON_CUSTOM_HEADER_SHIFT |
		packet_fmt);

	/* Older systems like MT8173 do not support size_con. */
	if (MTK_DSI_HAVE_SIZE_CON)
		write32(&dsi0->dsi_size_con,
			edid->mode.va << DSI_SIZE_CON_HEIGHT_SHIFT |
			hactive << DSI_SIZE_CON_WIDTH_SHIFT);
}

static void mtk_dsi_start(void)
{
	write32(&dsi0->dsi_start, 0);
	/* Only start master DSI */
	write32(&dsi0->dsi_start, 1);
}

static bool mtk_dsi_is_read_command(u32 type)
{
	switch (type) {
	case MIPI_DSI_GENERIC_READ_REQUEST_0_PARAM:
	case MIPI_DSI_GENERIC_READ_REQUEST_1_PARAM:
	case MIPI_DSI_GENERIC_READ_REQUEST_2_PARAM:
	case MIPI_DSI_DCS_READ:
		return true;
	}
	return false;
}

static void mtk_dsi_cmdq(const u8 *data, u8 len, u32 type)
{
	const u8 *tx_buf = data;
	u32 config;
	int i, j;

	if (!wait_ms(20, !(read32(&dsi0->dsi_intsta) & DSI_BUSY))) {
		printk(BIOS_ERR, "%s: cannot get DSI ready for sending commands"
		       " after 20ms and the panel may not work properly.\n",
		       __func__);
		return;
	}
	write32(&dsi0->dsi_intsta, 0);

	if (mtk_dsi_is_read_command(type))
		config = BTA;
	else
		config = (len > 2) ? LONG_PACKET : SHORT_PACKET;

	if (len <= 2) {
		uint32_t val = (type << 8) | config;
		for (i = 0; i < len; i++)
			val |= tx_buf[i] << (i + 2) * 8;
		write32(&dsi0->dsi_cmdq[0], val);
		write32(&dsi0->dsi_cmdq_size, 1);
	} else {
		/* TODO(hungte) Replace by buffer_to_fifo32_prefix */
		write32(&dsi0->dsi_cmdq[0], (len << 16) | (type << 8) | config);
		for (i = 0; i < len; i += 4) {
			uint32_t val = 0;
			for (j = 0; j < MIN(len - i, 4); j++)
				val |= tx_buf[i + j] << j * 8;
			write32(&dsi0->dsi_cmdq[i / 4 + 1], val);
		}
		write32(&dsi0->dsi_cmdq_size, 1 + DIV_ROUND_UP(len, 4));
	}

	mtk_dsi_start();

	if (!wait_us(400, read32(&dsi0->dsi_intsta) & CMD_DONE_INT_FLAG)) {
		printk(BIOS_ERR, "%s: failed sending DSI command, "
		       "panel may not work.\n", __func__);
		return;
	}
}

static void mtk_dsi_send_init_commands(const u8 *buf)
{
	if (!buf)
		return;
	const struct lcm_init_command *init = (const void *)buf;

	/*
	 * The given commands should be in a buffer containing a packed array of
	 * lcm_init_command and each element may be in variable size so we have
	 * to parse and scan.
	 */

	for (; init->cmd != LCM_END_CMD; init = (const void *)buf) {
		/*
		 * For some commands like DELAY, the init->len should not be
		 * counted for buf.
		 */
		buf += sizeof(*init);

		u32 cmd = init->cmd, len = init->len;
		u32 type;

		switch (cmd) {
		case LCM_DELAY_CMD:
			mdelay(len);
			continue;

		case LCM_DCS_CMD:
			switch (len) {
			case 0:
				return;
			case 1:
				type = MIPI_DSI_DCS_SHORT_WRITE;
				break;
			case 2:
				type = MIPI_DSI_DCS_SHORT_WRITE_PARAM;
				break;
			default:
				type = MIPI_DSI_DCS_LONG_WRITE;
				break;
			}
			break;

		case LCM_GENERIC_CMD:
			switch (len) {
			case 0:
				type = MIPI_DSI_GENERIC_SHORT_WRITE_0_PARAM;
				break;
			case 1:
				type = MIPI_DSI_GENERIC_SHORT_WRITE_1_PARAM;
				break;
			case 2:
				type = MIPI_DSI_GENERIC_SHORT_WRITE_2_PARAM;
				break;
			default:
				type = MIPI_DSI_GENERIC_LONG_WRITE;
				break;
			}
			break;

		default:
			printk(BIOS_ERR, "%s: Unknown cmd: %d, "
			       "abort panel initialization.\n", __func__, cmd);
			return;

		}
		buf += len;
		mtk_dsi_cmdq(init->data, len, type);
	}
}

static void mtk_dsi_reset_dphy(void)
{
	setbits32(&dsi0->dsi_con_ctrl, DPHY_RESET);
	clrbits32(&dsi0->dsi_con_ctrl, DPHY_RESET);
}

int mtk_dsi_init(u32 mode_flags, u32 format, u32 lanes, const struct edid *edid,
		 const u8 *init_commands)
{
	u32 data_rate;
	u32 bits_per_pixel = mtk_dsi_get_bits_per_pixel(format);

	data_rate = mtk_dsi_get_data_rate(bits_per_pixel, lanes, edid);
	if (!data_rate)
		return -1;

	mtk_dsi_configure_mipi_tx(data_rate, lanes);
	mtk_dsi_reset();
	struct mtk_phy_timing phy_timing;
	mtk_dsi_phy_timing(data_rate, &phy_timing);
	mtk_dsi_rxtx_control(mode_flags, lanes);
	mdelay(1);
	mtk_dsi_reset_dphy();
	mtk_dsi_clk_hs_mode_disable();
	mtk_dsi_config_vdo_timing(mode_flags, format, lanes, edid, &phy_timing);
	mtk_dsi_clk_hs_mode_enable();
	mtk_dsi_send_init_commands(init_commands);
	mtk_dsi_set_mode(mode_flags);
	mtk_dsi_start();

	return 0;
}