root/sys/dev/pci/drm/i915/display/intel_dsb_buffer.c
// 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_display_types.h"
#include "intel_dsb_buffer.h"

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);
}

bool intel_dsb_buffer_create(struct intel_crtc *crtc, struct intel_dsb_buffer *dsb_buf, size_t size)
{
        struct drm_i915_private *i915 = to_i915(crtc->base.dev);
        struct drm_i915_gem_object *obj;
        struct i915_vma *vma;
        u32 *buf;

        if (HAS_LMEM(i915)) {
                obj = i915_gem_object_create_lmem(i915, PAGE_ALIGN(size),
                                                  I915_BO_ALLOC_CONTIGUOUS);
                if (IS_ERR(obj))
                        return false;
        } else {
                obj = i915_gem_object_create_internal(i915, PAGE_ALIGN(size));
                if (IS_ERR(obj))
                        return false;

                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)) {
                i915_gem_object_put(obj);
                return false;
        }

        buf = i915_gem_object_pin_map_unlocked(vma->obj, I915_MAP_WC);
        if (IS_ERR(buf)) {
                i915_vma_unpin_and_release(&vma, I915_VMA_RELEASE_MAP);
                return false;
        }

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

        return true;
}

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

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