xref: /linux/drivers/gpu/drm/i915/display/intel_dsb_buffer.c (revision c0d6f52f9b62479d61f8cd4faf9fb2f8bce6e301)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright 2023, Intel Corporation.
4  */
5 
6 #include "gem/i915_gem_internal.h"
7 #include "gem/i915_gem_lmem.h"
8 #include "i915_drv.h"
9 #include "i915_vma.h"
10 #include "intel_dsb_buffer.h"
11 
12 struct intel_dsb_buffer {
13 	u32 *cmd_buf;
14 	struct i915_vma *vma;
15 	size_t buf_size;
16 };
17 
18 u32 intel_dsb_buffer_ggtt_offset(struct intel_dsb_buffer *dsb_buf)
19 {
20 	return i915_ggtt_offset(dsb_buf->vma);
21 }
22 
23 void intel_dsb_buffer_write(struct intel_dsb_buffer *dsb_buf, u32 idx, u32 val)
24 {
25 	dsb_buf->cmd_buf[idx] = val;
26 }
27 
28 u32 intel_dsb_buffer_read(struct intel_dsb_buffer *dsb_buf, u32 idx)
29 {
30 	return dsb_buf->cmd_buf[idx];
31 }
32 
33 void intel_dsb_buffer_memset(struct intel_dsb_buffer *dsb_buf, u32 idx, u32 val, size_t size)
34 {
35 	WARN_ON(idx > (dsb_buf->buf_size - size) / sizeof(*dsb_buf->cmd_buf));
36 
37 	memset(&dsb_buf->cmd_buf[idx], val, size);
38 }
39 
40 struct intel_dsb_buffer *intel_dsb_buffer_create(struct drm_device *drm, size_t size)
41 {
42 	struct drm_i915_private *i915 = to_i915(drm);
43 	struct intel_dsb_buffer *dsb_buf;
44 	struct drm_i915_gem_object *obj;
45 	struct i915_vma *vma;
46 	u32 *buf;
47 	int ret;
48 
49 	dsb_buf = kzalloc(sizeof(*dsb_buf), GFP_KERNEL);
50 	if (!dsb_buf)
51 		return ERR_PTR(-ENOMEM);
52 
53 	if (HAS_LMEM(i915)) {
54 		obj = i915_gem_object_create_lmem(i915, PAGE_ALIGN(size),
55 						  I915_BO_ALLOC_CONTIGUOUS);
56 		if (IS_ERR(obj)) {
57 			ret = PTR_ERR(obj);
58 			goto err;
59 		}
60 	} else {
61 		obj = i915_gem_object_create_internal(i915, PAGE_ALIGN(size));
62 		if (IS_ERR(obj)) {
63 			ret = PTR_ERR(obj);
64 			goto err;
65 		}
66 
67 		i915_gem_object_set_cache_coherency(obj, I915_CACHE_NONE);
68 	}
69 
70 	vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, 0);
71 	if (IS_ERR(vma)) {
72 		ret = PTR_ERR(vma);
73 		i915_gem_object_put(obj);
74 		goto err;
75 	}
76 
77 	buf = i915_gem_object_pin_map_unlocked(vma->obj, I915_MAP_WC);
78 	if (IS_ERR(buf)) {
79 		ret = PTR_ERR(buf);
80 		i915_vma_unpin_and_release(&vma, I915_VMA_RELEASE_MAP);
81 		goto err;
82 	}
83 
84 	dsb_buf->vma = vma;
85 	dsb_buf->cmd_buf = buf;
86 	dsb_buf->buf_size = size;
87 
88 	return dsb_buf;
89 
90 err:
91 	kfree(dsb_buf);
92 
93 	return ERR_PTR(ret);
94 }
95 
96 void intel_dsb_buffer_cleanup(struct intel_dsb_buffer *dsb_buf)
97 {
98 	i915_vma_unpin_and_release(&dsb_buf->vma, I915_VMA_RELEASE_MAP);
99 	kfree(dsb_buf);
100 }
101 
102 void intel_dsb_buffer_flush_map(struct intel_dsb_buffer *dsb_buf)
103 {
104 	i915_gem_object_flush_map(dsb_buf->vma->obj);
105 }
106