1/* SPDX-License-Identifier: MIT */
2/*
3 * Copyright © 2023 Intel Corporation
4 */
5
6#include <drm/drm_fb_helper.h>
7
8#include "gem/i915_gem_lmem.h"
9
10#include "i915_drv.h"
11#include "intel_display_types.h"
12#include "intel_fbdev_fb.h"
13
14struct drm_framebuffer *intel_fbdev_fb_alloc(struct drm_fb_helper *helper,
15 struct drm_fb_helper_surface_size *sizes)
16{
17 struct drm_framebuffer *fb;
18 struct drm_device *dev = helper->dev;
19 struct drm_i915_private *dev_priv = to_i915(dev);
20 struct drm_mode_fb_cmd2 mode_cmd = {};
21 struct drm_i915_gem_object *obj;
22 int size;
23
24 /* we don't do packed 24bpp */
25 if (sizes->surface_bpp == 24)
26 sizes->surface_bpp = 32;
27
28 mode_cmd.width = sizes->surface_width;
29 mode_cmd.height = sizes->surface_height;
30
31 mode_cmd.pitches[0] = ALIGN(mode_cmd.width *
32 DIV_ROUND_UP(sizes->surface_bpp, 8), 64);
33 mode_cmd.pixel_format = drm_mode_legacy_fb_format(bpp: sizes->surface_bpp,
34 depth: sizes->surface_depth);
35
36 size = mode_cmd.pitches[0] * mode_cmd.height;
37 size = PAGE_ALIGN(size);
38
39 obj = ERR_PTR(error: -ENODEV);
40 if (HAS_LMEM(dev_priv)) {
41 obj = i915_gem_object_create_lmem(i915: dev_priv, size,
42 I915_BO_ALLOC_CONTIGUOUS |
43 I915_BO_ALLOC_USER);
44 } else {
45 /*
46 * If the FB is too big, just don't use it since fbdev is not very
47 * important and we should probably use that space with FBC or other
48 * features.
49 *
50 * Also skip stolen on MTL as Wa_22018444074 mitigation.
51 */
52 if (!(IS_METEORLAKE(dev_priv)) && size * 2 < dev_priv->dsm.usable_size)
53 obj = i915_gem_object_create_stolen(dev_priv, size);
54 if (IS_ERR(ptr: obj))
55 obj = i915_gem_object_create_shmem(i915: dev_priv, size);
56 }
57
58 if (IS_ERR(ptr: obj)) {
59 drm_err(&dev_priv->drm, "failed to allocate framebuffer (%pe)\n", obj);
60 return ERR_PTR(error: -ENOMEM);
61 }
62
63 fb = intel_framebuffer_create(obj, mode_cmd: &mode_cmd);
64 i915_gem_object_put(obj);
65
66 return fb;
67}
68
69int intel_fbdev_fb_fill_info(struct drm_i915_private *i915, struct fb_info *info,
70 struct drm_i915_gem_object *obj, struct i915_vma *vma)
71{
72 struct i915_gem_ww_ctx ww;
73 void __iomem *vaddr;
74 int ret;
75
76 if (i915_gem_object_is_lmem(obj)) {
77 struct intel_memory_region *mem = obj->mm.region;
78
79 /* Use fbdev's framebuffer from lmem for discrete */
80 info->fix.smem_start =
81 (unsigned long)(mem->io.start +
82 i915_gem_object_get_dma_address(obj, 0) -
83 mem->region.start);
84 info->fix.smem_len = obj->base.size;
85 } else {
86 struct i915_ggtt *ggtt = to_gt(i915)->ggtt;
87
88 /* Our framebuffer is the entirety of fbdev's system memory */
89 info->fix.smem_start =
90 (unsigned long)(ggtt->gmadr.start + i915_ggtt_offset(vma));
91 info->fix.smem_len = vma->size;
92 }
93
94 for_i915_gem_ww(&ww, ret, false) {
95 ret = i915_gem_object_lock(obj: vma->obj, ww: &ww);
96
97 if (ret)
98 continue;
99
100 vaddr = i915_vma_pin_iomap(vma);
101 if (IS_ERR(ptr: vaddr)) {
102 drm_err(&i915->drm,
103 "Failed to remap framebuffer into virtual memory (%pe)\n", vaddr);
104 ret = PTR_ERR(ptr: vaddr);
105 continue;
106 }
107 }
108
109 if (ret)
110 return ret;
111
112 info->screen_base = vaddr;
113 info->screen_size = intel_bo_to_drm_bo(obj)->size;
114
115 return 0;
116}
117

source code of linux/drivers/gpu/drm/i915/display/intel_fbdev_fb.c