xref: /linux/drivers/gpu/drm/msm/msm_fbdev.c (revision f6e8dc9edf963dbc99085e54f6ced6da9daa6100)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2013 Red Hat
4  * Author: Rob Clark <robdclark@gmail.com>
5  */
6 
7 #include <linux/fb.h>
8 
9 #include <drm/drm_drv.h>
10 #include <drm/drm_crtc_helper.h>
11 #include <drm/drm_fb_helper.h>
12 #include <drm/drm_fourcc.h>
13 #include <drm/drm_framebuffer.h>
14 #include <drm/drm_prime.h>
15 
16 #include "msm_drv.h"
17 #include "msm_gem.h"
18 #include "msm_kms.h"
19 
20 static bool fbdev = true;
21 MODULE_PARM_DESC(fbdev, "Enable fbdev compat layer");
22 module_param(fbdev, bool, 0600);
23 
24 /*
25  * fbdev funcs, to implement legacy fbdev interface on top of drm driver
26  */
27 
28 FB_GEN_DEFAULT_DEFERRED_SYSMEM_OPS(msm_fbdev,
29 				   drm_fb_helper_damage_range,
30 				   drm_fb_helper_damage_area)
31 
32 static int msm_fbdev_mmap(struct fb_info *info, struct vm_area_struct *vma)
33 {
34 	struct drm_fb_helper *helper = (struct drm_fb_helper *)info->par;
35 	struct drm_gem_object *bo = msm_framebuffer_bo(helper->fb, 0);
36 
37 	return drm_gem_prime_mmap(bo, vma);
38 }
39 
40 static void msm_fbdev_fb_destroy(struct fb_info *info)
41 {
42 	struct drm_fb_helper *helper = (struct drm_fb_helper *)info->par;
43 	struct drm_framebuffer *fb = helper->fb;
44 	struct drm_gem_object *bo = msm_framebuffer_bo(fb, 0);
45 
46 	DBG();
47 
48 	drm_fb_helper_fini(helper);
49 
50 	/* this will free the backing object */
51 	msm_gem_put_vaddr(bo);
52 	drm_framebuffer_remove(fb);
53 
54 	drm_client_release(&helper->client);
55 }
56 
57 static const struct fb_ops msm_fb_ops = {
58 	.owner = THIS_MODULE,
59 	__FB_DEFAULT_DEFERRED_OPS_RDWR(msm_fbdev),
60 	DRM_FB_HELPER_DEFAULT_OPS,
61 	__FB_DEFAULT_DEFERRED_OPS_DRAW(msm_fbdev),
62 	.fb_mmap = msm_fbdev_mmap,
63 	.fb_destroy = msm_fbdev_fb_destroy,
64 };
65 
66 static int msm_fbdev_fb_dirty(struct drm_fb_helper *helper,
67 			      struct drm_clip_rect *clip)
68 {
69 	struct drm_device *dev = helper->dev;
70 	int ret;
71 
72 	/* Call damage handlers only if necessary */
73 	if (!(clip->x1 < clip->x2 && clip->y1 < clip->y2))
74 		return 0;
75 
76 	if (helper->fb->funcs->dirty) {
77 		ret = helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, clip, 1);
78 		if (drm_WARN_ONCE(dev, ret, "Dirty helper failed: ret=%d\n", ret))
79 			return ret;
80 	}
81 
82 	return 0;
83 }
84 
85 static const struct drm_fb_helper_funcs msm_fbdev_helper_funcs = {
86 	.fb_dirty = msm_fbdev_fb_dirty,
87 };
88 
89 int msm_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
90 				 struct drm_fb_helper_surface_size *sizes)
91 {
92 	struct drm_device *dev = helper->dev;
93 	struct msm_drm_private *priv = dev->dev_private;
94 	struct drm_framebuffer *fb = NULL;
95 	struct drm_gem_object *bo;
96 	struct fb_info *fbi = NULL;
97 	uint64_t paddr;
98 	uint32_t format;
99 	int ret, pitch;
100 
101 	format = drm_mode_legacy_fb_format(sizes->surface_bpp, sizes->surface_depth);
102 
103 	DBG("create fbdev: %dx%d@%d (%dx%d)", sizes->surface_width,
104 			sizes->surface_height, sizes->surface_bpp,
105 			sizes->fb_width, sizes->fb_height);
106 
107 	pitch = align_pitch(sizes->surface_width, sizes->surface_bpp);
108 	fb = msm_alloc_stolen_fb(dev, sizes->surface_width,
109 			sizes->surface_height, pitch, format);
110 
111 	if (IS_ERR(fb)) {
112 		DRM_DEV_ERROR(dev->dev, "failed to allocate fb\n");
113 		return PTR_ERR(fb);
114 	}
115 
116 	bo = msm_framebuffer_bo(fb, 0);
117 
118 	/*
119 	 * NOTE: if we can be guaranteed to be able to map buffer
120 	 * in panic (ie. lock-safe, etc) we could avoid pinning the
121 	 * buffer now:
122 	 */
123 	ret = msm_gem_get_and_pin_iova(bo, priv->kms->vm, &paddr);
124 	if (ret) {
125 		DRM_DEV_ERROR(dev->dev, "failed to get buffer obj iova: %d\n", ret);
126 		goto fail;
127 	}
128 
129 	fbi = drm_fb_helper_alloc_info(helper);
130 	if (IS_ERR(fbi)) {
131 		DRM_DEV_ERROR(dev->dev, "failed to allocate fb info\n");
132 		ret = PTR_ERR(fbi);
133 		goto fail;
134 	}
135 
136 	DBG("fbi=%p, dev=%p", fbi, dev);
137 
138 	helper->funcs = &msm_fbdev_helper_funcs;
139 	helper->fb = fb;
140 
141 	fbi->fbops = &msm_fb_ops;
142 
143 	drm_fb_helper_fill_info(fbi, helper, sizes);
144 
145 	fbi->screen_buffer = msm_gem_get_vaddr(bo);
146 	if (IS_ERR(fbi->screen_buffer)) {
147 		ret = PTR_ERR(fbi->screen_buffer);
148 		goto fail;
149 	}
150 	fbi->screen_size = bo->size;
151 	fbi->fix.smem_start = paddr;
152 	fbi->fix.smem_len = bo->size;
153 
154 	DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres);
155 	DBG("allocated %dx%d fb", fb->width, fb->height);
156 
157 	return 0;
158 
159 fail:
160 	drm_framebuffer_remove(fb);
161 	return ret;
162 }
163