xref: /linux/drivers/gpu/drm/msm/msm_fbdev.c (revision fdc290ff4ab19c7e0dde36c4cd1e2771b61f6bf5)
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_file.h>
13 #include <drm/drm_fourcc.h>
14 #include <drm/drm_framebuffer.h>
15 #include <drm/drm_prime.h>
16 
17 #include "msm_drv.h"
18 #include "msm_gem.h"
19 #include "msm_kms.h"
20 
21 static bool fbdev = true;
22 MODULE_PARM_DESC(fbdev, "Enable fbdev compat layer");
23 module_param(fbdev, bool, 0600);
24 
25 /*
26  * fbdev funcs, to implement legacy fbdev interface on top of drm driver
27  */
28 
29 FB_GEN_DEFAULT_DEFERRED_SYSMEM_OPS(msm_fbdev,
30 				   drm_fb_helper_damage_range,
31 				   drm_fb_helper_damage_area)
32 
33 static int msm_fbdev_mmap(struct fb_info *info, struct vm_area_struct *vma)
34 {
35 	struct drm_fb_helper *helper = (struct drm_fb_helper *)info->par;
36 	struct drm_gem_object *bo = msm_framebuffer_bo(helper->fb, 0);
37 
38 	return drm_gem_prime_mmap(bo, vma);
39 }
40 
41 static void msm_fbdev_fb_destroy(struct fb_info *info)
42 {
43 	struct drm_fb_helper *helper = (struct drm_fb_helper *)info->par;
44 	struct drm_gem_object *bo = msm_framebuffer_bo(helper->fb, 0);
45 
46 	DBG();
47 
48 	drm_fb_helper_fini(helper);
49 
50 	msm_gem_put_vaddr(bo);
51 
52 	drm_client_buffer_delete(helper->buffer);
53 	drm_client_release(&helper->client);
54 }
55 
56 static const struct fb_ops msm_fb_ops = {
57 	.owner = THIS_MODULE,
58 	__FB_DEFAULT_DEFERRED_OPS_RDWR(msm_fbdev),
59 	DRM_FB_HELPER_DEFAULT_OPS,
60 	__FB_DEFAULT_DEFERRED_OPS_DRAW(msm_fbdev),
61 	.fb_mmap = msm_fbdev_mmap,
62 	.fb_destroy = msm_fbdev_fb_destroy,
63 };
64 
65 static int msm_fbdev_fb_dirty(struct drm_fb_helper *helper,
66 			      struct drm_clip_rect *clip)
67 {
68 	struct drm_device *dev = helper->dev;
69 	int ret;
70 
71 	/* Call damage handlers only if necessary */
72 	if (!(clip->x1 < clip->x2 && clip->y1 < clip->y2))
73 		return 0;
74 
75 	if (helper->fb->funcs->dirty) {
76 		ret = helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, clip, 1);
77 		if (drm_WARN_ONCE(dev, ret, "Dirty helper failed: ret=%d\n", ret))
78 			return ret;
79 	}
80 
81 	return 0;
82 }
83 
84 static const struct drm_fb_helper_funcs msm_fbdev_helper_funcs = {
85 	.fb_dirty = msm_fbdev_fb_dirty,
86 };
87 
88 int msm_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
89 				 struct drm_fb_helper_surface_size *sizes)
90 {
91 	struct drm_client_dev *client = &helper->client;
92 	struct drm_device *dev = client->dev;
93 	struct drm_file *file = client->file;
94 	struct msm_drm_private *priv = dev->dev_private;
95 	struct fb_info *fbi = helper->info;
96 	const struct drm_format_info *format;
97 	u32 fourcc, pitch, handle;
98 	u64 size;
99 	struct drm_gem_object *bo;
100 	struct drm_client_buffer *buffer;
101 	uint64_t paddr;
102 	int ret;
103 
104 	DBG("create fbdev: %dx%d@%d (%dx%d)", sizes->surface_width,
105 			sizes->surface_height, sizes->surface_bpp,
106 			sizes->fb_width, sizes->fb_height);
107 
108 	fourcc = drm_mode_legacy_fb_format(sizes->surface_bpp, sizes->surface_depth);
109 	format = drm_get_format_info(dev, fourcc, DRM_FORMAT_MOD_LINEAR);
110 	/* adreno needs pitch aligned to 32 pixels: */
111 	pitch = drm_format_info_min_pitch(format, 0, ALIGN(sizes->surface_width, 32));
112 	size = ALIGN(pitch * sizes->surface_height, PAGE_SIZE);
113 
114 	/* allocate backing bo */
115 	DBG("allocating %llu bytes for fb %d", size, dev->primary->index);
116 	bo = msm_gem_new(dev, size, MSM_BO_SCANOUT | MSM_BO_WC | MSM_BO_STOLEN, NULL);
117 	if (IS_ERR(bo)) {
118 		drm_warn(dev, "could not allocate stolen bo\n");
119 		/* try regular bo: */
120 		bo = msm_gem_new(dev, size, MSM_BO_SCANOUT | MSM_BO_WC, NULL);
121 		if (IS_ERR(bo)) {
122 			drm_err(dev, "failed to allocate buffer object\n");
123 			return PTR_ERR(bo);
124 		}
125 	}
126 
127 	msm_gem_object_set_name(bo, "stolenfb");
128 
129 	ret = drm_gem_handle_create(file, bo, &handle);
130 	if (ret)
131 		goto err_drm_gem_object_put;
132 
133 	buffer = drm_client_buffer_create(client, sizes->surface_width, sizes->surface_height,
134 					  fourcc, handle, pitch);
135 	if (IS_ERR(buffer)) {
136 		ret = PTR_ERR(buffer);
137 		goto err_drm_gem_handle_delete;
138 	}
139 
140 	/*
141 	 * NOTE: if we can be guaranteed to be able to map buffer
142 	 * in panic (ie. lock-safe, etc) we could avoid pinning the
143 	 * buffer now:
144 	 */
145 	ret = msm_gem_get_and_pin_iova(bo, priv->kms->vm, &paddr);
146 	if (ret) {
147 		drm_err(dev, "failed to get buffer obj iova: %d\n", ret);
148 		goto err_drm_client_buffer_delete;
149 	}
150 
151 	DBG("fbi=%p, dev=%p", fbi, dev);
152 
153 	helper->funcs = &msm_fbdev_helper_funcs;
154 	helper->buffer = buffer;
155 	helper->fb = buffer->fb;
156 
157 	fbi->fbops = &msm_fb_ops;
158 
159 	drm_fb_helper_fill_info(fbi, helper, sizes);
160 
161 	fbi->screen_buffer = msm_gem_get_vaddr(bo);
162 	if (IS_ERR(fbi->screen_buffer)) {
163 		ret = PTR_ERR(fbi->screen_buffer);
164 		goto err_msm_gem_unpin;
165 	}
166 	fbi->screen_size = bo->size;
167 	fbi->fix.smem_start = paddr;
168 	fbi->fix.smem_len = bo->size;
169 
170 	DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres);
171 	DBG("allocated %dx%d fb", buffer->fb->width, buffer->fb->height);
172 
173 	/* The handle is only needed for creating the framebuffer. */
174 	drm_gem_handle_delete(file, handle);
175 
176 	/* The framebuffer still holds a reference on the GEM object. */
177 	drm_gem_object_put(bo);
178 
179 	return 0;
180 
181 err_msm_gem_unpin:
182 	msm_gem_unpin_iova(bo, priv->kms->vm);
183 	msm_gem_vma_put(bo);
184 err_drm_client_buffer_delete:
185 	drm_client_buffer_delete(buffer);
186 err_drm_gem_handle_delete:
187 	drm_gem_handle_delete(file, handle);
188 err_drm_gem_object_put:
189 	drm_gem_object_put(bo);
190 	return ret;
191 }
192