/*
 * Copyright © 2009 Intel Corporation
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include <linux/i2c.h>
#include <linux/pm_runtime.h>

#include <drm/drmP.h>
#include "framebuffer.h"
#include "psb_drv.h"
#include "psb_intel_drv.h"
#include "psb_intel_reg.h"
#include "gma_display.h"
#include "power.h"

struct psb_intel_range_t {
	int min, max;
};

struct oaktrail_limit_t {
	struct psb_intel_range_t dot, m, p1;
};

struct oaktrail_clock_t {
	/* derived values */
	int dot;
	int m;
	int p1;
};

#define MRST_LIMIT_LVDS_100L	    0
#define MRST_LIMIT_LVDS_83	    1
#define MRST_LIMIT_LVDS_100	    2

#define MRST_DOT_MIN		  19750
#define MRST_DOT_MAX		  120000
#define MRST_M_MIN_100L		    20
#define MRST_M_MIN_100		    10
#define MRST_M_MIN_83		    12
#define MRST_M_MAX_100L		    34
#define MRST_M_MAX_100		    17
#define MRST_M_MAX_83		    20
#define MRST_P1_MIN		    2
#define MRST_P1_MAX_0		    7
#define MRST_P1_MAX_1		    8

static const struct oaktrail_limit_t oaktrail_limits[] = {
	{			/* MRST_LIMIT_LVDS_100L */
	 .dot = {.min = MRST_DOT_MIN, .max = MRST_DOT_MAX},
	 .m = {.min = MRST_M_MIN_100L, .max = MRST_M_MAX_100L},
	 .p1 = {.min = MRST_P1_MIN, .max = MRST_P1_MAX_1},
	 },
	{			/* MRST_LIMIT_LVDS_83L */
	 .dot = {.min = MRST_DOT_MIN, .max = MRST_DOT_MAX},
	 .m = {.min = MRST_M_MIN_83, .max = MRST_M_MAX_83},
	 .p1 = {.min = MRST_P1_MIN, .max = MRST_P1_MAX_0},
	 },
	{			/* MRST_LIMIT_LVDS_100 */
	 .dot = {.min = MRST_DOT_MIN, .max = MRST_DOT_MAX},
	 .m = {.min = MRST_M_MIN_100, .max = MRST_M_MAX_100},
	 .p1 = {.min = MRST_P1_MIN, .max = MRST_P1_MAX_1},
	 },
};

#define MRST_M_MIN	    10
static const u32 oaktrail_m_converts[] = {
	0x2B, 0x15, 0x2A, 0x35, 0x1A, 0x0D, 0x26, 0x33, 0x19, 0x2C,
	0x36, 0x3B, 0x1D, 0x2E, 0x37, 0x1B, 0x2D, 0x16, 0x0B, 0x25,
	0x12, 0x09, 0x24, 0x32, 0x39, 0x1c,
};

static const struct oaktrail_limit_t *oaktrail_limit(struct drm_crtc *crtc)
{
	const struct oaktrail_limit_t *limit = NULL;
	struct drm_device *dev = crtc->dev;
	struct drm_psb_private *dev_priv = dev->dev_private;

	if (gma_pipe_has_type(crtc, INTEL_OUTPUT_LVDS)
	    || gma_pipe_has_type(crtc, INTEL_OUTPUT_MIPI)) {
		switch (dev_priv->core_freq) {
		case 100:
			limit = &oaktrail_limits[MRST_LIMIT_LVDS_100L];
			break;
		case 166:
			limit = &oaktrail_limits[MRST_LIMIT_LVDS_83];
			break;
		case 200:
			limit = &oaktrail_limits[MRST_LIMIT_LVDS_100];
			break;
		}
	} else {
		limit = NULL;
		dev_err(dev->dev, "oaktrail_limit Wrong display type.\n");
	}

	return limit;
}

/** Derive the pixel clock for the given refclk and divisors for 8xx chips. */
static void oaktrail_clock(int refclk, struct oaktrail_clock_t *clock)
{
	clock->dot = (refclk * clock->m) / (14 * clock->p1);
}

static void mrstPrintPll(char *prefix, struct oaktrail_clock_t *clock)
{
	pr_debug("%s: dotclock = %d,  m = %d, p1 = %d.\n",
	     prefix, clock->dot, clock->m, clock->p1);
}

/**
 * Returns a set of divisors for the desired target clock with the given refclk,
 * or FALSE.  Divisor values are the actual divisors for
 */
static bool
mrstFindBestPLL(struct drm_crtc *crtc, int target, int refclk,
		struct oaktrail_clock_t *best_clock)
{
	struct oaktrail_clock_t clock;
	const struct oaktrail_limit_t *limit = oaktrail_limit(crtc);
	int err = target;

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

	for (clock.m = limit->m.min; clock.m <= limit->m.max; clock.m++) {
		for (clock.p1 = limit->p1.min; clock.p1 <= limit->p1.max;
		     clock.p1++) {
			int this_err;

			oaktrail_clock(refclk, &clock);

			this_err = abs(clock.dot - target);
			if (this_err < err) {
				*best_clock = clock;
				err = this_err;
			}
		}
	}
	dev_dbg(crtc->dev->dev, "mrstFindBestPLL err = %d.\n", err);
	return err != target;
}

/**
 * Sets the power management mode of the pipe and plane.
 *
 * This code should probably grow support for turning the cursor off and back
 * on appropriately at the same time as we're turning the pipe off/on.
 */
static void oaktrail_crtc_dpms(struct drm_crtc *crtc, int mode)
{
	struct drm_device *dev = crtc->dev;
	struct drm_psb_private *dev_priv = dev->dev_private;
	struct psb_intel_crtc *psb_intel_crtc = to_psb_intel_crtc(crtc);
	int pipe = psb_intel_crtc->pipe;
	const struct psb_offset *map = &dev_priv->regmap[pipe];
	u32 temp;

	if (pipe == 1) {
		oaktrail_crtc_hdmi_dpms(crtc, mode);
		return;
	}

	if (!gma_power_begin(dev, true))
		return;

	/* XXX: When our outputs are all unaware of DPMS modes other than off
	 * and on, we should map those modes to DRM_MODE_DPMS_OFF in the CRTC.
	 */
	switch (mode) {
	case DRM_MODE_DPMS_ON:
	case DRM_MODE_DPMS_STANDBY:
	case DRM_MODE_DPMS_SUSPEND:
		/* Enable the DPLL */
		temp = REG_READ(map->dpll);
		if ((temp & DPLL_VCO_ENABLE) == 0) {
			REG_WRITE(map->dpll, temp);
			REG_READ(map->dpll);
			/* Wait for the clocks to stabilize. */
			udelay(150);
			REG_WRITE(map->dpll, temp | DPLL_VCO_ENABLE);
			REG_READ(map->dpll);
			/* Wait for the clocks to stabilize. */
			udelay(150);
			REG_WRITE(map->dpll, temp | DPLL_VCO_ENABLE);
			REG_READ(map->dpll);
			/* Wait for the clocks to stabilize. */
			udelay(150);
		}
		/* Enable the pipe */
		temp = REG_READ(map->conf);
		if ((temp & PIPEACONF_ENABLE) == 0)
			REG_WRITE(map->conf, temp | PIPEACONF_ENABLE);
		/* Enable the plane */
		temp = REG_READ(map->cntr);
		if ((temp & DISPLAY_PLANE_ENABLE) == 0) {
			REG_WRITE(map->cntr,
				  temp | DISPLAY_PLANE_ENABLE);
			/* Flush the plane changes */
			REG_WRITE(map->base, REG_READ(map->base));
		}

		gma_crtc_load_lut(crtc);

		/* Give the overlay scaler a chance to enable
		   if it's on this pipe */
		/* psb_intel_crtc_dpms_video(crtc, true); TODO */
		break;
	case DRM_MODE_DPMS_OFF:
		/* Give the overlay scaler a chance to disable
		 * if it's on this pipe */
		/* psb_intel_crtc_dpms_video(crtc, FALSE); TODO */

		/* Disable the VGA plane that we never use */
		REG_WRITE(VGACNTRL, VGA_DISP_DISABLE);
		/* Disable display plane */
		temp = REG_READ(map->cntr);
		if ((temp & DISPLAY_PLANE_ENABLE) != 0) {
			REG_WRITE(map->cntr,
				  temp & ~DISPLAY_PLANE_ENABLE);
			/* Flush the plane changes */
			REG_WRITE(map->base, REG_READ(map->base));
			REG_READ(map->base);
		}

		/* Next, disable display pipes */
		temp = REG_READ(map->conf);
		if ((temp & PIPEACONF_ENABLE) != 0) {
			REG_WRITE(map->conf, temp & ~PIPEACONF_ENABLE);
			REG_READ(map->conf);
		}
		/* Wait for for the pipe disable to take effect. */
		gma_wait_for_vblank(dev);

		temp = REG_READ(map->dpll);
		if ((temp & DPLL_VCO_ENABLE) != 0) {
			REG_WRITE(map->dpll, temp & ~DPLL_VCO_ENABLE);
			REG_READ(map->dpll);
		}

		/* Wait for the clocks to turn off. */
		udelay(150);
		break;
	}

	/*Set FIFO Watermarks*/
	REG_WRITE(DSPARB, 0x3FFF);
	REG_WRITE(DSPFW1, 0x3F88080A);
	REG_WRITE(DSPFW2, 0x0b060808);
	REG_WRITE(DSPFW3, 0x0);
	REG_WRITE(DSPFW4, 0x08030404);
	REG_WRITE(DSPFW5, 0x04040404);
	REG_WRITE(DSPFW6, 0x78);
	REG_WRITE(0x70400, REG_READ(0x70400) | 0x4000);
	/* Must write Bit 14 of the Chicken Bit Register */

	gma_power_end(dev);
}

/**
 * Return the pipe currently connected to the panel fitter,
 * or -1 if the panel fitter is not present or not in use
 */
static int oaktrail_panel_fitter_pipe(struct drm_device *dev)
{
	u32 pfit_control;

	pfit_control = REG_READ(PFIT_CONTROL);

	/* See if the panel fitter is in use */
	if ((pfit_control & PFIT_ENABLE) == 0)
		return -1;
	return (pfit_control >> 29) & 3;
}

static int oaktrail_crtc_mode_set(struct drm_crtc *crtc,
			      struct drm_display_mode *mode,
			      struct drm_display_mode *adjusted_mode,
			      int x, int y,
			      struct drm_framebuffer *old_fb)
{
	struct drm_device *dev = crtc->dev;
	struct psb_intel_crtc *psb_intel_crtc = to_psb_intel_crtc(crtc);
	struct drm_psb_private *dev_priv = dev->dev_private;
	int pipe = psb_intel_crtc->pipe;
	const struct psb_offset *map = &dev_priv->regmap[pipe];
	int refclk = 0;
	struct oaktrail_clock_t clock;
	u32 dpll = 0, fp = 0, dspcntr, pipeconf;
	bool ok, is_sdvo = false;
	bool is_lvds = false;
	bool is_mipi = false;
	struct drm_mode_config *mode_config = &dev->mode_config;
	struct psb_intel_encoder *psb_intel_encoder = NULL;
	uint64_t scalingType = DRM_MODE_SCALE_FULLSCREEN;
	struct drm_connector *connector;

	if (pipe == 1)
		return oaktrail_crtc_hdmi_mode_set(crtc, mode, adjusted_mode, x, y, old_fb);

	if (!gma_power_begin(dev, true))
		return 0;

	memcpy(&psb_intel_crtc->saved_mode,
		mode,
		sizeof(struct drm_display_mode));
	memcpy(&psb_intel_crtc->saved_adjusted_mode,
		adjusted_mode,
		sizeof(struct drm_display_mode));

	list_for_each_entry(connector, &mode_config->connector_list, head) {
		if (!connector->encoder || connector->encoder->crtc != crtc)
			continue;

		psb_intel_encoder = psb_intel_attached_encoder(connector);

		switch (psb_intel_encoder->type) {
		case INTEL_OUTPUT_LVDS:
			is_lvds = true;
			break;
		case INTEL_OUTPUT_SDVO:
			is_sdvo = true;
			break;
		case INTEL_OUTPUT_MIPI:
			is_mipi = true;
			break;
		}
	}

	/* Disable the VGA plane that we never use */
	REG_WRITE(VGACNTRL, VGA_DISP_DISABLE);

	/* Disable the panel fitter if it was on our pipe */
	if (oaktrail_panel_fitter_pipe(dev) == pipe)
		REG_WRITE(PFIT_CONTROL, 0);

	REG_WRITE(map->src,
		  ((mode->crtc_hdisplay - 1) << 16) |
		  (mode->crtc_vdisplay - 1));

	if (psb_intel_encoder)
		drm_object_property_get_value(&connector->base,
			dev->mode_config.scaling_mode_property, &scalingType);

	if (scalingType == DRM_MODE_SCALE_NO_SCALE) {
		/* Moorestown doesn't have register support for centering so
		 * we need to mess with the h/vblank and h/vsync start and
		 * ends to get centering */
		int offsetX = 0, offsetY = 0;

		offsetX = (adjusted_mode->crtc_hdisplay -
			   mode->crtc_hdisplay) / 2;
		offsetY = (adjusted_mode->crtc_vdisplay -
			   mode->crtc_vdisplay) / 2;

		REG_WRITE(map->htotal, (mode->crtc_hdisplay - 1) |
			((adjusted_mode->crtc_htotal - 1) << 16));
		REG_WRITE(map->vtotal, (mode->crtc_vdisplay - 1) |
			((adjusted_mode->crtc_vtotal - 1) << 16));
		REG_WRITE(map->hblank,
			(adjusted_mode->crtc_hblank_start - offsetX - 1) |
			((adjusted_mode->crtc_hblank_end - offsetX - 1) << 16));
		REG_WRITE(map->hsync,
			(adjusted_mode->crtc_hsync_start - offsetX - 1) |
			((adjusted_mode->crtc_hsync_end - offsetX - 1) << 16));
		REG_WRITE(map->vblank,
			(adjusted_mode->crtc_vblank_start - offsetY - 1) |
			((adjusted_mode->crtc_vblank_end - offsetY - 1) << 16));
		REG_WRITE(map->vsync,
			(adjusted_mode->crtc_vsync_start - offsetY - 1) |
			((adjusted_mode->crtc_vsync_end - offsetY - 1) << 16));
	} else {
		REG_WRITE(map->htotal, (adjusted_mode->crtc_hdisplay - 1) |
			((adjusted_mode->crtc_htotal - 1) << 16));
		REG_WRITE(map->vtotal, (adjusted_mode->crtc_vdisplay - 1) |
			((adjusted_mode->crtc_vtotal - 1) << 16));
		REG_WRITE(map->hblank, (adjusted_mode->crtc_hblank_start - 1) |
			((adjusted_mode->crtc_hblank_end - 1) << 16));
		REG_WRITE(map->hsync, (adjusted_mode->crtc_hsync_start - 1) |
			((adjusted_mode->crtc_hsync_end - 1) << 16));
		REG_WRITE(map->vblank, (adjusted_mode->crtc_vblank_start - 1) |
			((adjusted_mode->crtc_vblank_end - 1) << 16));
		REG_WRITE(map->vsync, (adjusted_mode->crtc_vsync_start - 1) |
			((adjusted_mode->crtc_vsync_end - 1) << 16));
	}

	/* Flush the plane changes */
	{
		struct drm_crtc_helper_funcs *crtc_funcs =
		    crtc->helper_private;
		crtc_funcs->mode_set_base(crtc, x, y, old_fb);
	}

	/* setup pipeconf */
	pipeconf = REG_READ(map->conf);

	/* Set up the display plane register */
	dspcntr = REG_READ(map->cntr);
	dspcntr |= DISPPLANE_GAMMA_ENABLE;

	if (pipe == 0)
		dspcntr |= DISPPLANE_SEL_PIPE_A;
	else
		dspcntr |= DISPPLANE_SEL_PIPE_B;

	if (is_mipi)
		goto oaktrail_crtc_mode_set_exit;

	refclk = dev_priv->core_freq * 1000;

	dpll = 0;		/*BIT16 = 0 for 100MHz reference */

	ok = mrstFindBestPLL(crtc, adjusted_mode->clock, refclk, &clock);

	if (!ok) {
		dev_dbg(dev->dev, "mrstFindBestPLL fail in oaktrail_crtc_mode_set.\n");
	} else {
		dev_dbg(dev->dev, "oaktrail_crtc_mode_set pixel clock = %d,"
			 "m = %x, p1 = %x.\n", clock.dot, clock.m,
			 clock.p1);
	}

	fp = oaktrail_m_converts[(clock.m - MRST_M_MIN)] << 8;

	dpll |= DPLL_VGA_MODE_DIS;


	dpll |= DPLL_VCO_ENABLE;

	if (is_lvds)
		dpll |= DPLLA_MODE_LVDS;
	else
		dpll |= DPLLB_MODE_DAC_SERIAL;

	if (is_sdvo) {
		int sdvo_pixel_multiply =
		    adjusted_mode->clock / mode->clock;

		dpll |= DPLL_DVO_HIGH_SPEED;
		dpll |=
		    (sdvo_pixel_multiply -
		     1) << SDVO_MULTIPLIER_SHIFT_HIRES;
	}


	/* compute bitmask from p1 value */
	dpll |= (1 << (clock.p1 - 2)) << 17;

	dpll |= DPLL_VCO_ENABLE;

	mrstPrintPll("chosen", &clock);

	if (dpll & DPLL_VCO_ENABLE) {
		REG_WRITE(map->fp0, fp);
		REG_WRITE(map->dpll, dpll & ~DPLL_VCO_ENABLE);
		REG_READ(map->dpll);
		/* Check the DPLLA lock bit PIPEACONF[29] */
		udelay(150);
	}

	REG_WRITE(map->fp0, fp);
	REG_WRITE(map->dpll, dpll);
	REG_READ(map->dpll);
	/* Wait for the clocks to stabilize. */
	udelay(150);

	/* write it again -- the BIOS does, after all */
	REG_WRITE(map->dpll, dpll);
	REG_READ(map->dpll);
	/* Wait for the clocks to stabilize. */
	udelay(150);

	REG_WRITE(map->conf, pipeconf);
	REG_READ(map->conf);
	gma_wait_for_vblank(dev);

	REG_WRITE(map->cntr, dspcntr);
	gma_wait_for_vblank(dev);

oaktrail_crtc_mode_set_exit:
	gma_power_end(dev);
	return 0;
}

static bool oaktrail_crtc_mode_fixup(struct drm_crtc *crtc,
				  const struct drm_display_mode *mode,
				  struct drm_display_mode *adjusted_mode)
{
	return true;
}

static int oaktrail_pipe_set_base(struct drm_crtc *crtc,
			    int x, int y, struct drm_framebuffer *old_fb)
{
	struct drm_device *dev = crtc->dev;
	struct drm_psb_private *dev_priv = dev->dev_private;
	struct psb_intel_crtc *psb_intel_crtc = to_psb_intel_crtc(crtc);
	struct psb_framebuffer *psbfb = to_psb_fb(crtc->fb);
	int pipe = psb_intel_crtc->pipe;
	const struct psb_offset *map = &dev_priv->regmap[pipe];
	unsigned long start, offset;

	u32 dspcntr;
	int ret = 0;

	/* no fb bound */
	if (!crtc->fb) {
		dev_dbg(dev->dev, "No FB bound\n");
		return 0;
	}

	if (!gma_power_begin(dev, true))
		return 0;

	start = psbfb->gtt->offset;
	offset = y * crtc->fb->pitches[0] + x * (crtc->fb->bits_per_pixel / 8);

	REG_WRITE(map->stride, crtc->fb->pitches[0]);

	dspcntr = REG_READ(map->cntr);
	dspcntr &= ~DISPPLANE_PIXFORMAT_MASK;

	switch (crtc->fb->bits_per_pixel) {
	case 8:
		dspcntr |= DISPPLANE_8BPP;
		break;
	case 16:
		if (crtc->fb->depth == 15)
			dspcntr |= DISPPLANE_15_16BPP;
		else
			dspcntr |= DISPPLANE_16BPP;
		break;
	case 24:
	case 32:
		dspcntr |= DISPPLANE_32BPP_NO_ALPHA;
		break;
	default:
		dev_err(dev->dev, "Unknown color depth\n");
		ret = -EINVAL;
		goto pipe_set_base_exit;
	}
	REG_WRITE(map->cntr, dspcntr);

	REG_WRITE(map->base, offset);
	REG_READ(map->base);
	REG_WRITE(map->surf, start);
	REG_READ(map->surf);

pipe_set_base_exit:
	gma_power_end(dev);
	return ret;
}

static void oaktrail_crtc_prepare(struct drm_crtc *crtc)
{
	struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
	crtc_funcs->dpms(crtc, DRM_MODE_DPMS_OFF);
}

static void oaktrail_crtc_commit(struct drm_crtc *crtc)
{
	struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
	crtc_funcs->dpms(crtc, DRM_MODE_DPMS_ON);
}

const struct drm_crtc_helper_funcs oaktrail_helper_funcs = {
	.dpms = oaktrail_crtc_dpms,
	.mode_fixup = oaktrail_crtc_mode_fixup,
	.mode_set = oaktrail_crtc_mode_set,
	.mode_set_base = oaktrail_pipe_set_base,
	.prepare = oaktrail_crtc_prepare,
	.commit = oaktrail_crtc_commit,
};