xref: /linux/drivers/gpu/drm/i915/display/intel_fbdev_fb.c (revision 22c55fb9eb92395d999b8404d73e58540d11bdd8)
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_core.h"
12 #include "intel_display_types.h"
13 #include "intel_fb.h"
14 #include "intel_fbdev_fb.h"
15 
16 struct intel_framebuffer *intel_fbdev_fb_alloc(struct drm_fb_helper *helper,
17 					       struct drm_fb_helper_surface_size *sizes)
18 {
19 	struct intel_display *display = to_intel_display(helper->dev);
20 	struct drm_i915_private *dev_priv = to_i915(display->drm);
21 	struct drm_framebuffer *fb;
22 	struct drm_mode_fb_cmd2 mode_cmd = {};
23 	struct drm_i915_gem_object *obj;
24 	int size;
25 
26 	/* we don't do packed 24bpp */
27 	if (sizes->surface_bpp == 24)
28 		sizes->surface_bpp = 32;
29 
30 	mode_cmd.width = sizes->surface_width;
31 	mode_cmd.height = sizes->surface_height;
32 
33 	mode_cmd.pitches[0] = ALIGN(mode_cmd.width *
34 				    DIV_ROUND_UP(sizes->surface_bpp, 8), 64);
35 	mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
36 							  sizes->surface_depth);
37 
38 	size = mode_cmd.pitches[0] * mode_cmd.height;
39 	size = PAGE_ALIGN(size);
40 
41 	obj = ERR_PTR(-ENODEV);
42 	if (HAS_LMEM(dev_priv)) {
43 		obj = i915_gem_object_create_lmem(dev_priv, size,
44 						  I915_BO_ALLOC_CONTIGUOUS |
45 						  I915_BO_ALLOC_USER);
46 	} else {
47 		/*
48 		 * If the FB is too big, just don't use it since fbdev is not very
49 		 * important and we should probably use that space with FBC or other
50 		 * features.
51 		 *
52 		 * Also skip stolen on MTL as Wa_22018444074 mitigation.
53 		 */
54 		if (!display->platform.meteorlake && size * 2 < dev_priv->dsm.usable_size)
55 			obj = i915_gem_object_create_stolen(dev_priv, size);
56 		if (IS_ERR(obj))
57 			obj = i915_gem_object_create_shmem(dev_priv, size);
58 	}
59 
60 	if (IS_ERR(obj)) {
61 		drm_err(display->drm, "failed to allocate framebuffer (%pe)\n", obj);
62 		return ERR_PTR(-ENOMEM);
63 	}
64 
65 	fb = intel_framebuffer_create(intel_bo_to_drm_bo(obj),
66 				      drm_get_format_info(display->drm,
67 							  mode_cmd.pixel_format,
68 							  mode_cmd.modifier[0]),
69 				      &mode_cmd);
70 	i915_gem_object_put(obj);
71 
72 	return to_intel_framebuffer(fb);
73 }
74 
75 int intel_fbdev_fb_fill_info(struct intel_display *display, struct fb_info *info,
76 			     struct drm_gem_object *_obj, struct i915_vma *vma)
77 {
78 	struct drm_i915_private *i915 = to_i915(display->drm);
79 	struct drm_i915_gem_object *obj = to_intel_bo(_obj);
80 	struct i915_gem_ww_ctx ww;
81 	void __iomem *vaddr;
82 	int ret;
83 
84 	if (i915_gem_object_is_lmem(obj)) {
85 		struct intel_memory_region *mem = obj->mm.region;
86 
87 		/* Use fbdev's framebuffer from lmem for discrete */
88 		info->fix.smem_start =
89 			(unsigned long)(mem->io.start +
90 					i915_gem_object_get_dma_address(obj, 0) -
91 					mem->region.start);
92 		info->fix.smem_len = obj->base.size;
93 	} else {
94 		struct i915_ggtt *ggtt = to_gt(i915)->ggtt;
95 
96 		/* Our framebuffer is the entirety of fbdev's system memory */
97 		info->fix.smem_start =
98 			(unsigned long)(ggtt->gmadr.start + i915_ggtt_offset(vma));
99 		info->fix.smem_len = vma->size;
100 	}
101 
102 	for_i915_gem_ww(&ww, ret, false) {
103 		ret = i915_gem_object_lock(vma->obj, &ww);
104 
105 		if (ret)
106 			continue;
107 
108 		vaddr = i915_vma_pin_iomap(vma);
109 		if (IS_ERR(vaddr)) {
110 			drm_err(display->drm,
111 				"Failed to remap framebuffer into virtual memory (%pe)\n", vaddr);
112 			ret = PTR_ERR(vaddr);
113 			continue;
114 		}
115 	}
116 
117 	if (ret)
118 		return ret;
119 
120 	info->screen_base = vaddr;
121 	info->screen_size = intel_bo_to_drm_bo(obj)->size;
122 
123 	return 0;
124 }
125