xref: /linux/drivers/gpu/drm/msm/msm_fbdev.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
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 	drm_fb_helper_unprepare(helper);
56 	kfree(helper);
57 }
58 
59 static const struct fb_ops msm_fb_ops = {
60 	.owner = THIS_MODULE,
61 	__FB_DEFAULT_DEFERRED_OPS_RDWR(msm_fbdev),
62 	DRM_FB_HELPER_DEFAULT_OPS,
63 	__FB_DEFAULT_DEFERRED_OPS_DRAW(msm_fbdev),
64 	.fb_mmap = msm_fbdev_mmap,
65 	.fb_destroy = msm_fbdev_fb_destroy,
66 };
67 
68 static int msm_fbdev_fb_dirty(struct drm_fb_helper *helper,
69 			      struct drm_clip_rect *clip)
70 {
71 	struct drm_device *dev = helper->dev;
72 	int ret;
73 
74 	/* Call damage handlers only if necessary */
75 	if (!(clip->x1 < clip->x2 && clip->y1 < clip->y2))
76 		return 0;
77 
78 	if (helper->fb->funcs->dirty) {
79 		ret = helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, clip, 1);
80 		if (drm_WARN_ONCE(dev, ret, "Dirty helper failed: ret=%d\n", ret))
81 			return ret;
82 	}
83 
84 	return 0;
85 }
86 
87 static const struct drm_fb_helper_funcs msm_fbdev_helper_funcs = {
88 	.fb_dirty = msm_fbdev_fb_dirty,
89 };
90 
91 int msm_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
92 				 struct drm_fb_helper_surface_size *sizes)
93 {
94 	struct drm_device *dev = helper->dev;
95 	struct msm_drm_private *priv = dev->dev_private;
96 	struct drm_framebuffer *fb = NULL;
97 	struct drm_gem_object *bo;
98 	struct fb_info *fbi = NULL;
99 	uint64_t paddr;
100 	uint32_t format;
101 	int ret, pitch;
102 
103 	format = drm_mode_legacy_fb_format(sizes->surface_bpp, sizes->surface_depth);
104 
105 	DBG("create fbdev: %dx%d@%d (%dx%d)", sizes->surface_width,
106 			sizes->surface_height, sizes->surface_bpp,
107 			sizes->fb_width, sizes->fb_height);
108 
109 	pitch = align_pitch(sizes->surface_width, sizes->surface_bpp);
110 	fb = msm_alloc_stolen_fb(dev, sizes->surface_width,
111 			sizes->surface_height, pitch, format);
112 
113 	if (IS_ERR(fb)) {
114 		DRM_DEV_ERROR(dev->dev, "failed to allocate fb\n");
115 		return PTR_ERR(fb);
116 	}
117 
118 	bo = msm_framebuffer_bo(fb, 0);
119 
120 	/*
121 	 * NOTE: if we can be guaranteed to be able to map buffer
122 	 * in panic (ie. lock-safe, etc) we could avoid pinning the
123 	 * buffer now:
124 	 */
125 	ret = msm_gem_get_and_pin_iova(bo, priv->kms->aspace, &paddr);
126 	if (ret) {
127 		DRM_DEV_ERROR(dev->dev, "failed to get buffer obj iova: %d\n", ret);
128 		goto fail;
129 	}
130 
131 	fbi = drm_fb_helper_alloc_info(helper);
132 	if (IS_ERR(fbi)) {
133 		DRM_DEV_ERROR(dev->dev, "failed to allocate fb info\n");
134 		ret = PTR_ERR(fbi);
135 		goto fail;
136 	}
137 
138 	DBG("fbi=%p, dev=%p", fbi, dev);
139 
140 	helper->funcs = &msm_fbdev_helper_funcs;
141 	helper->fb = fb;
142 
143 	fbi->fbops = &msm_fb_ops;
144 
145 	drm_fb_helper_fill_info(fbi, helper, sizes);
146 
147 	fbi->screen_buffer = msm_gem_get_vaddr(bo);
148 	if (IS_ERR(fbi->screen_buffer)) {
149 		ret = PTR_ERR(fbi->screen_buffer);
150 		goto fail;
151 	}
152 	fbi->screen_size = bo->size;
153 	fbi->fix.smem_start = paddr;
154 	fbi->fix.smem_len = bo->size;
155 
156 	DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres);
157 	DBG("allocated %dx%d fb", fb->width, fb->height);
158 
159 	return 0;
160 
161 fail:
162 	drm_framebuffer_remove(fb);
163 	return ret;
164 }
165