/*
 * Copyright (C) STMicroelectronics SA 2014
 * Authors: Benjamin Gaignard <benjamin.gaignard@st.com>
 *          Fabien Dessenne <fabien.dessenne@st.com>
 *          for STMicroelectronics.
 * License terms:  GNU General Public License (GPL), version 2
 */

#include "sti_compositor.h"
#include "sti_mixer.h"
#include "sti_vtg.h"

/* Module parameter to set the background color of the mixer */
static unsigned int bkg_color = 0x000000;
MODULE_PARM_DESC(bkgcolor, "Value of the background color 0xRRGGBB");
module_param_named(bkgcolor, bkg_color, int, 0644);

/* Identity: G=Y , B=Cb , R=Cr */
static const u32 mixerColorSpaceMatIdentity[] = {
	0x10000000, 0x00000000, 0x10000000, 0x00001000,
	0x00000000, 0x00000000, 0x00000000, 0x00000000
};

/* regs offset */
#define GAM_MIXER_CTL      0x00
#define GAM_MIXER_BKC      0x04
#define GAM_MIXER_BCO      0x0C
#define GAM_MIXER_BCS      0x10
#define GAM_MIXER_AVO      0x28
#define GAM_MIXER_AVS      0x2C
#define GAM_MIXER_CRB      0x34
#define GAM_MIXER_ACT      0x38
#define GAM_MIXER_MBP      0x3C
#define GAM_MIXER_MX0      0x80

/* id for depth of CRB reg */
#define GAM_DEPTH_VID0_ID  1
#define GAM_DEPTH_VID1_ID  2
#define GAM_DEPTH_GDP0_ID  3
#define GAM_DEPTH_GDP1_ID  4
#define GAM_DEPTH_GDP2_ID  5
#define GAM_DEPTH_GDP3_ID  6
#define GAM_DEPTH_MASK_ID  7

/* mask in CTL reg */
#define GAM_CTL_BACK_MASK  BIT(0)
#define GAM_CTL_VID0_MASK  BIT(1)
#define GAM_CTL_VID1_MASK  BIT(2)
#define GAM_CTL_GDP0_MASK  BIT(3)
#define GAM_CTL_GDP1_MASK  BIT(4)
#define GAM_CTL_GDP2_MASK  BIT(5)
#define GAM_CTL_GDP3_MASK  BIT(6)
#define GAM_CTL_CURSOR_MASK BIT(9)

const char *sti_mixer_to_str(struct sti_mixer *mixer)
{
	switch (mixer->id) {
	case STI_MIXER_MAIN:
		return "MAIN_MIXER";
	case STI_MIXER_AUX:
		return "AUX_MIXER";
	default:
		return "<UNKNOWN MIXER>";
	}
}

static inline u32 sti_mixer_reg_read(struct sti_mixer *mixer, u32 reg_id)
{
	return readl(mixer->regs + reg_id);
}

static inline void sti_mixer_reg_write(struct sti_mixer *mixer,
				       u32 reg_id, u32 val)
{
	writel(val, mixer->regs + reg_id);
}

void sti_mixer_set_background_status(struct sti_mixer *mixer, bool enable)
{
	u32 val = sti_mixer_reg_read(mixer, GAM_MIXER_CTL);

	val &= ~GAM_CTL_BACK_MASK;
	val |= enable;
	sti_mixer_reg_write(mixer, GAM_MIXER_CTL, val);
}

static void sti_mixer_set_background_color(struct sti_mixer *mixer,
					   unsigned int rgb)
{
	sti_mixer_reg_write(mixer, GAM_MIXER_BKC, rgb);
}

static void sti_mixer_set_background_area(struct sti_mixer *mixer,
					  struct drm_display_mode *mode)
{
	u32 ydo, xdo, yds, xds;

	ydo = sti_vtg_get_line_number(*mode, 0);
	yds = sti_vtg_get_line_number(*mode, mode->vdisplay - 1);
	xdo = sti_vtg_get_pixel_number(*mode, 0);
	xds = sti_vtg_get_pixel_number(*mode, mode->hdisplay - 1);

	sti_mixer_reg_write(mixer, GAM_MIXER_BCO, ydo << 16 | xdo);
	sti_mixer_reg_write(mixer, GAM_MIXER_BCS, yds << 16 | xds);
}

int sti_mixer_set_plane_depth(struct sti_mixer *mixer, struct sti_plane *plane)
{
	int plane_id, depth = plane->zorder;
	unsigned int i;
	u32 mask, val;

	if ((depth < 1) || (depth > GAM_MIXER_NB_DEPTH_LEVEL))
		return 1;

	switch (plane->desc) {
	case STI_GDP_0:
		plane_id = GAM_DEPTH_GDP0_ID;
		break;
	case STI_GDP_1:
		plane_id = GAM_DEPTH_GDP1_ID;
		break;
	case STI_GDP_2:
		plane_id = GAM_DEPTH_GDP2_ID;
		break;
	case STI_GDP_3:
		plane_id = GAM_DEPTH_GDP3_ID;
		break;
	case STI_HQVDP_0:
		plane_id = GAM_DEPTH_VID0_ID;
		break;
	case STI_CURSOR:
		/* no need to set depth for cursor */
		return 0;
	default:
		DRM_ERROR("Unknown plane %d\n", plane->desc);
		return 1;
	}

	/* Search if a previous depth was already assigned to the plane */
	val = sti_mixer_reg_read(mixer, GAM_MIXER_CRB);
	for (i = 0; i < GAM_MIXER_NB_DEPTH_LEVEL; i++) {
		mask = GAM_DEPTH_MASK_ID << (3 * i);
		if ((val & mask) == plane_id << (3 * i))
			break;
	}

	mask |= GAM_DEPTH_MASK_ID << (3 * (depth - 1));
	plane_id = plane_id << (3 * (depth - 1));

	DRM_DEBUG_DRIVER("%s %s depth=%d\n", sti_mixer_to_str(mixer),
			 sti_plane_to_str(plane), depth);
	dev_dbg(mixer->dev, "GAM_MIXER_CRB val 0x%x mask 0x%x\n",
		plane_id, mask);

	val &= ~mask;
	val |= plane_id;
	sti_mixer_reg_write(mixer, GAM_MIXER_CRB, val);

	dev_dbg(mixer->dev, "Read GAM_MIXER_CRB 0x%x\n",
		sti_mixer_reg_read(mixer, GAM_MIXER_CRB));
	return 0;
}

int sti_mixer_active_video_area(struct sti_mixer *mixer,
				struct drm_display_mode *mode)
{
	u32 ydo, xdo, yds, xds;

	ydo = sti_vtg_get_line_number(*mode, 0);
	yds = sti_vtg_get_line_number(*mode, mode->vdisplay - 1);
	xdo = sti_vtg_get_pixel_number(*mode, 0);
	xds = sti_vtg_get_pixel_number(*mode, mode->hdisplay - 1);

	DRM_DEBUG_DRIVER("%s active video area xdo:%d ydo:%d xds:%d yds:%d\n",
			 sti_mixer_to_str(mixer), xdo, ydo, xds, yds);
	sti_mixer_reg_write(mixer, GAM_MIXER_AVO, ydo << 16 | xdo);
	sti_mixer_reg_write(mixer, GAM_MIXER_AVS, yds << 16 | xds);

	sti_mixer_set_background_color(mixer, bkg_color);

	sti_mixer_set_background_area(mixer, mode);
	sti_mixer_set_background_status(mixer, true);
	return 0;
}

static u32 sti_mixer_get_plane_mask(struct sti_plane *plane)
{
	switch (plane->desc) {
	case STI_BACK:
		return GAM_CTL_BACK_MASK;
	case STI_GDP_0:
		return GAM_CTL_GDP0_MASK;
	case STI_GDP_1:
		return GAM_CTL_GDP1_MASK;
	case STI_GDP_2:
		return GAM_CTL_GDP2_MASK;
	case STI_GDP_3:
		return GAM_CTL_GDP3_MASK;
	case STI_HQVDP_0:
		return GAM_CTL_VID0_MASK;
	case STI_CURSOR:
		return GAM_CTL_CURSOR_MASK;
	default:
		return 0;
	}
}

int sti_mixer_set_plane_status(struct sti_mixer *mixer,
			       struct sti_plane *plane, bool status)
{
	u32 mask, val;

	DRM_DEBUG_DRIVER("%s %s %s\n", status ? "enable" : "disable",
			 sti_mixer_to_str(mixer), sti_plane_to_str(plane));

	mask = sti_mixer_get_plane_mask(plane);
	if (!mask) {
		DRM_ERROR("Can't find layer mask\n");
		return -EINVAL;
	}

	val = sti_mixer_reg_read(mixer, GAM_MIXER_CTL);
	val &= ~mask;
	val |= status ? mask : 0;
	sti_mixer_reg_write(mixer, GAM_MIXER_CTL, val);

	return 0;
}

void sti_mixer_set_matrix(struct sti_mixer *mixer)
{
	unsigned int i;

	for (i = 0; i < ARRAY_SIZE(mixerColorSpaceMatIdentity); i++)
		sti_mixer_reg_write(mixer, GAM_MIXER_MX0 + (i * 4),
				    mixerColorSpaceMatIdentity[i]);
}

struct sti_mixer *sti_mixer_create(struct device *dev, int id,
				   void __iomem *baseaddr)
{
	struct sti_mixer *mixer = devm_kzalloc(dev, sizeof(*mixer), GFP_KERNEL);
	struct device_node *np = dev->of_node;

	dev_dbg(dev, "%s\n", __func__);
	if (!mixer) {
		DRM_ERROR("Failed to allocated memory for mixer\n");
		return NULL;
	}
	mixer->regs = baseaddr;
	mixer->dev = dev;
	mixer->id = id;

	if (of_device_is_compatible(np, "st,stih416-compositor"))
		sti_mixer_set_matrix(mixer);

	DRM_DEBUG_DRIVER("%s created. Regs=%p\n",
			 sti_mixer_to_str(mixer), mixer->regs);

	return mixer;
}