// SPDX-License-Identifier: MIT
/*
 * Copyright 2023, Intel Corporation.
 */

#include "gem/i915_gem_internal.h"
#include "gem/i915_gem_lmem.h"
#include "i915_drv.h"
#include "i915_vma.h"
#include "intel_dsb_buffer.h"

struct intel_dsb_buffer {
        u32 *cmd_buf;
        struct i915_vma *vma;
        size_t buf_size;
};

u32 intel_dsb_buffer_ggtt_offset(struct intel_dsb_buffer *dsb_buf)
{
        return i915_ggtt_offset(dsb_buf->vma);
}

void intel_dsb_buffer_write(struct intel_dsb_buffer *dsb_buf, u32 idx, u32 val)
{
        dsb_buf->cmd_buf[idx] = val;
}

u32 intel_dsb_buffer_read(struct intel_dsb_buffer *dsb_buf, u32 idx)
{
        return dsb_buf->cmd_buf[idx];
}

void intel_dsb_buffer_memset(struct intel_dsb_buffer *dsb_buf, u32 idx, u32 val, size_t size)
{
        WARN_ON(idx > (dsb_buf->buf_size - size) / sizeof(*dsb_buf->cmd_buf));

        memset(&dsb_buf->cmd_buf[idx], val, size);
}

struct intel_dsb_buffer *intel_dsb_buffer_create(struct drm_device *drm, size_t size)
{
        struct drm_i915_private *i915 = to_i915(drm);
        struct intel_dsb_buffer *dsb_buf;
        struct drm_i915_gem_object *obj;
        struct i915_vma *vma;
        u32 *buf;
        int ret;

        dsb_buf = kzalloc_obj(*dsb_buf);
        if (!dsb_buf)
                return ERR_PTR(-ENOMEM);

        if (HAS_LMEM(i915)) {
                obj = i915_gem_object_create_lmem(i915, PAGE_ALIGN(size),
                                                  I915_BO_ALLOC_CONTIGUOUS);
                if (IS_ERR(obj)) {
                        ret = PTR_ERR(obj);
                        goto err;
                }
        } else {
                obj = i915_gem_object_create_internal(i915, PAGE_ALIGN(size));
                if (IS_ERR(obj)) {
                        ret = PTR_ERR(obj);
                        goto err;
                }

                i915_gem_object_set_cache_coherency(obj, I915_CACHE_NONE);
        }

        vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, 0);
        if (IS_ERR(vma)) {
                ret = PTR_ERR(vma);
                i915_gem_object_put(obj);
                goto err;
        }

        buf = i915_gem_object_pin_map_unlocked(vma->obj, I915_MAP_WC);
        if (IS_ERR(buf)) {
                ret = PTR_ERR(buf);
                i915_vma_unpin_and_release(&vma, I915_VMA_RELEASE_MAP);
                goto err;
        }

        dsb_buf->vma = vma;
        dsb_buf->cmd_buf = buf;
        dsb_buf->buf_size = size;

        return dsb_buf;

err:
        kfree(dsb_buf);

        return ERR_PTR(ret);
}

void intel_dsb_buffer_cleanup(struct intel_dsb_buffer *dsb_buf)
{
        i915_vma_unpin_and_release(&dsb_buf->vma, I915_VMA_RELEASE_MAP);
        kfree(dsb_buf);
}

void intel_dsb_buffer_flush_map(struct intel_dsb_buffer *dsb_buf)
{
        i915_gem_object_flush_map(dsb_buf->vma->obj);
}