/*
 * Copyright 2014 The Chromium OS Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#ifdef DRV_I915

#include <errno.h>
#include <i915_drm.h>
#include <intel_bufmgr.h>
#include <string.h>
#include <sys/mman.h>
#include <xf86drm.h>

#include "drv_priv.h"
#include "helpers.h"
#include "util.h"

static struct supported_combination combos[19] = {
	{DRM_FORMAT_ARGB1555, DRM_FORMAT_MOD_NONE,
		BO_USE_RENDERING | BO_USE_SW_READ_RARELY | BO_USE_SW_WRITE_RARELY},
	{DRM_FORMAT_ABGR8888, DRM_FORMAT_MOD_NONE,
		BO_USE_RENDERING | BO_USE_SW_READ_OFTEN | BO_USE_SW_WRITE_OFTEN},
	{DRM_FORMAT_ABGR8888, DRM_FORMAT_MOD_NONE,
		BO_USE_RENDERING | BO_USE_SW_READ_RARELY | BO_USE_SW_WRITE_RARELY},
	{DRM_FORMAT_ARGB8888, DRM_FORMAT_MOD_NONE,
		BO_USE_CURSOR | BO_USE_LINEAR | BO_USE_SW_READ_OFTEN | BO_USE_SW_WRITE_OFTEN},
	{DRM_FORMAT_ARGB8888, DRM_FORMAT_MOD_NONE,
		BO_USE_RENDERING | BO_USE_SW_READ_RARELY | BO_USE_SW_WRITE_RARELY},
	{DRM_FORMAT_GR88, DRM_FORMAT_MOD_NONE,
		BO_USE_LINEAR | BO_USE_SW_READ_OFTEN | BO_USE_SW_WRITE_OFTEN},
	{DRM_FORMAT_R8, DRM_FORMAT_MOD_NONE,
		BO_USE_LINEAR | BO_USE_SW_READ_OFTEN | BO_USE_SW_WRITE_OFTEN},
	{DRM_FORMAT_RGB565, DRM_FORMAT_MOD_NONE,
		BO_USE_RENDERING | BO_USE_SW_READ_RARELY | BO_USE_SW_WRITE_RARELY},
	{DRM_FORMAT_UYVY, DRM_FORMAT_MOD_NONE,
		BO_USE_LINEAR | BO_USE_SW_READ_OFTEN | BO_USE_SW_WRITE_OFTEN},
	{DRM_FORMAT_UYVY, DRM_FORMAT_MOD_NONE,
		BO_USE_RENDERING | BO_USE_SW_READ_RARELY | BO_USE_SW_WRITE_RARELY},
	{DRM_FORMAT_XBGR8888, DRM_FORMAT_MOD_NONE,
		BO_USE_RENDERING | BO_USE_SW_READ_OFTEN | BO_USE_SW_WRITE_OFTEN},
	{DRM_FORMAT_XBGR8888, DRM_FORMAT_MOD_NONE,
		BO_USE_RENDERING | BO_USE_SW_READ_RARELY | BO_USE_SW_WRITE_RARELY},
	{DRM_FORMAT_XRGB1555, DRM_FORMAT_MOD_NONE,
		BO_USE_RENDERING | BO_USE_SW_READ_RARELY | BO_USE_SW_WRITE_RARELY},
	{DRM_FORMAT_XRGB8888, DRM_FORMAT_MOD_NONE,
		BO_USE_CURSOR | BO_USE_LINEAR | BO_USE_SW_READ_OFTEN | BO_USE_SW_WRITE_OFTEN},
	{DRM_FORMAT_XRGB8888, DRM_FORMAT_MOD_NONE,
		BO_USE_RENDERING | BO_USE_SW_READ_RARELY | BO_USE_SW_WRITE_RARELY},
	{DRM_FORMAT_YUYV, DRM_FORMAT_MOD_NONE,
		BO_USE_LINEAR | BO_USE_SW_READ_OFTEN | BO_USE_SW_WRITE_OFTEN},
	{DRM_FORMAT_YUYV, DRM_FORMAT_MOD_NONE,
		BO_USE_RENDERING | BO_USE_SW_READ_RARELY | BO_USE_SW_WRITE_RARELY},
	{DRM_FORMAT_YVU420, DRM_FORMAT_MOD_NONE,
		BO_USE_RENDERING | BO_USE_SW_READ_RARELY | BO_USE_SW_WRITE_RARELY},
	{DRM_FORMAT_YVU420, DRM_FORMAT_MOD_NONE,
		BO_USE_LINEAR | BO_USE_SW_READ_OFTEN | BO_USE_SW_WRITE_OFTEN},
};

struct i915_device
{
	int gen;
	drm_intel_bufmgr *mgr;
	uint32_t count;
};

struct i915_bo
{
	drm_intel_bo *ibos[DRV_MAX_PLANES];
};

static int get_gen(int device_id)
{
	const uint16_t gen3_ids[] = {0x2582, 0x2592, 0x2772, 0x27A2, 0x27AE,
				     0x29C2, 0x29B2, 0x29D2, 0xA001, 0xA011};
	unsigned i;
	for(i = 0; i < ARRAY_SIZE(gen3_ids); i++)
		if (gen3_ids[i] == device_id)
			return 3;

	return 4;
}

static void i915_align_dimensions(struct driver *drv, uint32_t tiling_mode,
				  uint32_t *width, uint32_t *height, int bpp)
{
	struct i915_device *i915_dev = (struct i915_device *)drv->priv;
	uint32_t width_alignment = 4, height_alignment = 4;

	switch (tiling_mode) {
	default:
	case I915_TILING_NONE:
		width_alignment = 64 / bpp;
		break;

	case I915_TILING_X:
		width_alignment = 512 / bpp;
		height_alignment = 8;
		break;

	case I915_TILING_Y:
		if (i915_dev->gen == 3) {
			width_alignment = 512 / bpp;
			height_alignment = 8;
		} else  {
			width_alignment = 128 / bpp;
			height_alignment = 32;
		}
		break;
	}

	if (i915_dev->gen > 3) {
		*width = ALIGN(*width, width_alignment);
		*height = ALIGN(*height, height_alignment);
	} else {
		uint32_t w;
		for (w = width_alignment; w < *width;  w <<= 1)
			;
		*width = w;
		*height = ALIGN(*height, height_alignment);
	}
}

static int i915_verify_dimensions(struct driver *drv, uint32_t stride,
				  uint32_t height)
{
	struct i915_device *i915_dev = (struct i915_device *)drv->priv;
	if (i915_dev->gen <= 3 && stride > 8192)
		return 0;

	return 1;
}

static int i915_init(struct driver *drv)
{
	struct i915_device *i915_dev;
	drm_i915_getparam_t get_param;
	int device_id;
	int ret;

	i915_dev = calloc(1, sizeof(*i915_dev));
	if (!i915_dev)
		return -1;

	memset(&get_param, 0, sizeof(get_param));
	get_param.param = I915_PARAM_CHIPSET_ID;
	get_param.value = &device_id;
	ret = drmIoctl(drv->fd, DRM_IOCTL_I915_GETPARAM, &get_param);
	if (ret) {
		fprintf(stderr, "drv: DRM_IOCTL_I915_GETPARAM failed\n");
		free(i915_dev);
		return -EINVAL;
	}

	i915_dev->gen = get_gen(device_id);
	i915_dev->count = 0;

	i915_dev->mgr = drm_intel_bufmgr_gem_init(drv->fd, 16 * 1024);
	if (!i915_dev->mgr) {
		fprintf(stderr, "drv: drm_intel_bufmgr_gem_init failed\n");
		free(i915_dev);
		return -EINVAL;
	}

	drv->priv = i915_dev;

	drv_insert_combinations(drv, combos, ARRAY_SIZE(combos));
	return drv_add_kms_flags(drv);
}

static void i915_close(struct driver *drv)
{
	struct i915_device *i915_dev = drv->priv;
	drm_intel_bufmgr_destroy(i915_dev->mgr);
	free(i915_dev);
	drv->priv = NULL;
}

static int i915_bo_create(struct bo *bo, uint32_t width, uint32_t height,
			  uint32_t format, uint32_t flags)
{
	int ret;
	size_t plane;
	char name[20];
	uint32_t tiling_mode;
	struct i915_bo *i915_bo;

	int bpp = drv_stride_from_format(format, 1, 0);
	struct i915_device *i915_dev = (struct i915_device *)bo->drv->priv;

	if (flags & (BO_USE_CURSOR | BO_USE_LINEAR |
		     BO_USE_SW_READ_OFTEN | BO_USE_SW_WRITE_OFTEN))
		tiling_mode = I915_TILING_NONE;
	else if (flags & BO_USE_SCANOUT)
		tiling_mode = I915_TILING_X;
	else
		tiling_mode = I915_TILING_Y;

	i915_align_dimensions(bo->drv, tiling_mode, &width, &height, bpp);
	drv_bo_from_format(bo, width, height, format);

	if (!i915_verify_dimensions(bo->drv, bo->strides[0], height))
		return -EINVAL;

	snprintf(name, sizeof(name), "i915-buffer-%u", i915_dev->count);
	i915_dev->count++;

	i915_bo = calloc(1, sizeof(*i915_bo));
	if (!i915_bo)
		return -ENOMEM;

	bo->priv = i915_bo;

	i915_bo->ibos[0] = drm_intel_bo_alloc(i915_dev->mgr, name,
					      bo->total_size, 0);
	if (!i915_bo->ibos[0]) {
		fprintf(stderr, "drv: drm_intel_bo_alloc failed");
		free(i915_bo);
		bo->priv = NULL;
		return -ENOMEM;
	}

	for (plane = 0; plane < bo->num_planes; plane++) {
		if (plane > 0)
			drm_intel_bo_reference(i915_bo->ibos[0]);

		bo->handles[plane].u32 = i915_bo->ibos[0]->handle;
		i915_bo->ibos[plane] = i915_bo->ibos[0];
	}

	bo->tiling = tiling_mode;

	ret = drm_intel_bo_set_tiling(i915_bo->ibos[0], &bo->tiling,
				      bo->strides[0]);

	if (ret || bo->tiling != tiling_mode) {
		fprintf(stderr, "drv: drm_intel_gem_bo_set_tiling failed "
			"errno=%x, stride=%x\n", errno, bo->strides[0]);
		/* Calls i915 bo destroy. */
		bo->drv->backend->bo_destroy(bo);
		return -errno;
	}

	return 0;
}

static int i915_bo_destroy(struct bo *bo)
{
	size_t plane;
	struct i915_bo *i915_bo = bo->priv;

	for (plane = 0; plane < bo->num_planes; plane++)
		drm_intel_bo_unreference(i915_bo->ibos[plane]);

	free(i915_bo);
	bo->priv = NULL;

	return 0;
}

static int i915_bo_import(struct bo *bo, struct drv_import_fd_data *data)
{
	size_t plane;
	uint32_t swizzling;
	struct i915_bo *i915_bo;
	struct i915_device *i915_dev = bo->drv->priv;

	i915_bo = calloc(1, sizeof(*i915_bo));
	if (!i915_bo)
		return -ENOMEM;

	bo->priv = i915_bo;

	/*
	 * When self-importing, libdrm_intel increments the reference count
	 * on the drm_intel_bo. It also returns the same drm_intel_bo per GEM
	 * handle. Thus, we don't need to increase the reference count
	 * (i.e, drv_increment_reference_count) when importing with this
	 * backend.
	 */
	for (plane = 0; plane < bo->num_planes; plane++) {

		i915_bo->ibos[plane] = drm_intel_bo_gem_create_from_prime(i915_dev->mgr,
				 data->fds[plane], data->sizes[plane]);

		if (!i915_bo->ibos[plane]) {
			/*
			 * Need to call GEM close on planes that were opened,
			 * if any. Adjust the num_planes variable to be the
			 * plane that failed, so GEM close will be called on
			 * planes before that plane.
			 */
			bo->num_planes = plane;
			i915_bo_destroy(bo);
			fprintf(stderr, "drv: i915: failed to import failed");
			return -EINVAL;
		}

		bo->handles[plane].u32 = i915_bo->ibos[plane]->handle;
	}

	if (drm_intel_bo_get_tiling(i915_bo->ibos[0], &bo->tiling,
				    &swizzling)) {
		fprintf(stderr, "drv: drm_intel_bo_get_tiling failed");
		i915_bo_destroy(bo);
		return -EINVAL;
	}

	return 0;
}

static void *i915_bo_map(struct bo *bo, struct map_info *data, size_t plane)
{
	int ret;
	struct i915_bo *i915_bo = bo->priv;

	if (bo->tiling == I915_TILING_NONE)
		/* TODO(gsingh): use bo_map flags to determine if we should
		 * enable writing.
		 */
		ret = drm_intel_bo_map(i915_bo->ibos[0], 1);
	else
		ret = drm_intel_gem_bo_map_gtt(i915_bo->ibos[0]);

	if (ret) {
		fprintf(stderr, "drv: i915_bo_map failed.");
		return MAP_FAILED;
	}

	return i915_bo->ibos[0]->virtual;
}

static int i915_bo_unmap(struct bo *bo, struct map_info *data)
{
	int ret;
	struct i915_bo *i915_bo = bo->priv;

	if (bo->tiling == I915_TILING_NONE)
		ret = drm_intel_bo_unmap(i915_bo->ibos[0]);
	else
		ret = drm_intel_gem_bo_unmap_gtt(i915_bo->ibos[0]);

	return ret;
}

static uint32_t i915_resolve_format(uint32_t format)
{
	switch (format) {
	case DRM_FORMAT_FLEX_IMPLEMENTATION_DEFINED:
		/*HACK: See b/28671744 */
		return DRM_FORMAT_XBGR8888;
	case DRM_FORMAT_FLEX_YCbCr_420_888:
		return DRM_FORMAT_YVU420;
	default:
		return format;
	}
}

struct backend backend_i915 =
{
	.name = "i915",
	.init = i915_init,
	.close = i915_close,
	.bo_create = i915_bo_create,
	.bo_destroy = i915_bo_destroy,
	.bo_import = i915_bo_import,
	.bo_map = i915_bo_map,
	.bo_unmap = i915_bo_unmap,
	.resolve_format = i915_resolve_format,
};

#endif