xref: /linux/drivers/gpu/drm/i915/display/intel_fbdev_fb.c (revision 9b286c3b0bc0e0f242b2495ccb1b3523d50be484)
1 /* SPDX-License-Identifier: MIT */
2 /*
3  * Copyright © 2023 Intel Corporation
4  */
5 
6 #include <linux/fb.h>
7 
8 #include "gem/i915_gem_lmem.h"
9 
10 #include "i915_drv.h"
11 #include "intel_fbdev_fb.h"
12 
13 u32 intel_fbdev_fb_pitch_align(u32 stride)
14 {
15 	return ALIGN(stride, 64);
16 }
17 
18 struct drm_gem_object *intel_fbdev_fb_bo_create(struct drm_device *drm, int size)
19 {
20 	struct drm_i915_private *dev_priv = to_i915(drm);
21 	struct drm_i915_gem_object *obj;
22 
23 	obj = ERR_PTR(-ENODEV);
24 	if (HAS_LMEM(dev_priv)) {
25 		obj = i915_gem_object_create_lmem(dev_priv, size,
26 						  I915_BO_ALLOC_CONTIGUOUS |
27 						  I915_BO_ALLOC_USER);
28 	} else {
29 		/*
30 		 * If the FB is too big, just don't use it since fbdev is not very
31 		 * important and we should probably use that space with FBC or other
32 		 * features.
33 		 *
34 		 * Also skip stolen on MTL as Wa_22018444074 mitigation.
35 		 */
36 		if (!IS_METEORLAKE(dev_priv) && size * 2 < dev_priv->dsm.usable_size)
37 			obj = i915_gem_object_create_stolen(dev_priv, size);
38 		if (IS_ERR(obj))
39 			obj = i915_gem_object_create_shmem(dev_priv, size);
40 	}
41 
42 	if (IS_ERR(obj)) {
43 		drm_err(drm, "failed to allocate framebuffer (%pe)\n", obj);
44 		return ERR_PTR(-ENOMEM);
45 	}
46 
47 	return &obj->base;
48 }
49 
50 void intel_fbdev_fb_bo_destroy(struct drm_gem_object *obj)
51 {
52 	drm_gem_object_put(obj);
53 }
54 
55 int intel_fbdev_fb_fill_info(struct drm_device *drm, struct fb_info *info,
56 			     struct drm_gem_object *_obj, struct i915_vma *vma)
57 {
58 	struct drm_i915_private *i915 = to_i915(drm);
59 	struct drm_i915_gem_object *obj = to_intel_bo(_obj);
60 	struct i915_gem_ww_ctx ww;
61 	void __iomem *vaddr;
62 	int ret;
63 
64 	if (i915_gem_object_is_lmem(obj)) {
65 		struct intel_memory_region *mem = obj->mm.region;
66 
67 		/* Use fbdev's framebuffer from lmem for discrete */
68 		info->fix.smem_start =
69 			(unsigned long)(mem->io.start +
70 					i915_gem_object_get_dma_address(obj, 0) -
71 					mem->region.start);
72 		info->fix.smem_len = obj->base.size;
73 	} else {
74 		struct i915_ggtt *ggtt = to_gt(i915)->ggtt;
75 
76 		/* Our framebuffer is the entirety of fbdev's system memory */
77 		info->fix.smem_start =
78 			(unsigned long)(ggtt->gmadr.start + i915_ggtt_offset(vma));
79 		info->fix.smem_len = vma->size;
80 	}
81 
82 	for_i915_gem_ww(&ww, ret, false) {
83 		ret = i915_gem_object_lock(vma->obj, &ww);
84 
85 		if (ret)
86 			continue;
87 
88 		vaddr = i915_vma_pin_iomap(vma);
89 		if (IS_ERR(vaddr)) {
90 			drm_err(drm,
91 				"Failed to remap framebuffer into virtual memory (%pe)\n", vaddr);
92 			ret = PTR_ERR(vaddr);
93 			continue;
94 		}
95 	}
96 
97 	if (ret)
98 		return ret;
99 
100 	info->screen_base = vaddr;
101 	info->screen_size = intel_bo_to_drm_bo(obj)->size;
102 
103 	return 0;
104 }
105