xref: /linux/drivers/gpu/drm/i915/display/intel_fbdev_fb.c (revision 815e260a18a3af4dab59025ee99a7156c0e8b5e0)
1 /* SPDX-License-Identifier: MIT */
2 /*
3  * Copyright © 2023 Intel Corporation
4  */
5 
6 #include <linux/fb.h>
7 
8 #include <drm/drm_print.h>
9 
10 #include "gem/i915_gem_lmem.h"
11 
12 #include "i915_drv.h"
13 #include "intel_fbdev_fb.h"
14 
15 u32 intel_fbdev_fb_pitch_align(u32 stride)
16 {
17 	return ALIGN(stride, 64);
18 }
19 
20 struct drm_gem_object *intel_fbdev_fb_bo_create(struct drm_device *drm, int size)
21 {
22 	struct drm_i915_private *dev_priv = to_i915(drm);
23 	struct drm_i915_gem_object *obj;
24 
25 	obj = ERR_PTR(-ENODEV);
26 	if (HAS_LMEM(dev_priv)) {
27 		obj = i915_gem_object_create_lmem(dev_priv, size,
28 						  I915_BO_ALLOC_CONTIGUOUS |
29 						  I915_BO_ALLOC_USER);
30 	} else {
31 		/*
32 		 * If the FB is too big, just don't use it since fbdev is not very
33 		 * important and we should probably use that space with FBC or other
34 		 * features.
35 		 *
36 		 * Also skip stolen on MTL as Wa_22018444074 mitigation.
37 		 */
38 		if (!IS_METEORLAKE(dev_priv) && size * 2 < dev_priv->dsm.usable_size)
39 			obj = i915_gem_object_create_stolen(dev_priv, size);
40 		if (IS_ERR(obj))
41 			obj = i915_gem_object_create_shmem(dev_priv, size);
42 	}
43 
44 	if (IS_ERR(obj)) {
45 		drm_err(drm, "failed to allocate framebuffer (%pe)\n", obj);
46 		return ERR_PTR(-ENOMEM);
47 	}
48 
49 	return &obj->base;
50 }
51 
52 void intel_fbdev_fb_bo_destroy(struct drm_gem_object *obj)
53 {
54 	drm_gem_object_put(obj);
55 }
56 
57 int intel_fbdev_fb_fill_info(struct drm_device *drm, struct fb_info *info,
58 			     struct drm_gem_object *_obj, struct i915_vma *vma)
59 {
60 	struct drm_i915_private *i915 = to_i915(drm);
61 	struct drm_i915_gem_object *obj = to_intel_bo(_obj);
62 	struct i915_gem_ww_ctx ww;
63 	void __iomem *vaddr;
64 	int ret;
65 
66 	if (i915_gem_object_is_lmem(obj)) {
67 		struct intel_memory_region *mem = obj->mm.region;
68 
69 		/* Use fbdev's framebuffer from lmem for discrete */
70 		info->fix.smem_start =
71 			(unsigned long)(mem->io.start +
72 					i915_gem_object_get_dma_address(obj, 0) -
73 					mem->region.start);
74 		info->fix.smem_len = obj->base.size;
75 	} else {
76 		struct i915_ggtt *ggtt = to_gt(i915)->ggtt;
77 
78 		/* Our framebuffer is the entirety of fbdev's system memory */
79 		info->fix.smem_start =
80 			(unsigned long)(ggtt->gmadr.start + i915_ggtt_offset(vma));
81 		info->fix.smem_len = vma->size;
82 	}
83 
84 	for_i915_gem_ww(&ww, ret, false) {
85 		ret = i915_gem_object_lock(vma->obj, &ww);
86 
87 		if (ret)
88 			continue;
89 
90 		vaddr = i915_vma_pin_iomap(vma);
91 		if (IS_ERR(vaddr)) {
92 			drm_err(drm,
93 				"Failed to remap framebuffer into virtual memory (%pe)\n", vaddr);
94 			ret = PTR_ERR(vaddr);
95 			continue;
96 		}
97 	}
98 
99 	if (ret)
100 		return ret;
101 
102 	info->screen_base = vaddr;
103 	info->screen_size = intel_bo_to_drm_bo(obj)->size;
104 
105 	return 0;
106 }
107