xref: /linux/drivers/gpu/drm/gma500/fbdev.c (revision 07fdad3a93756b872da7b53647715c48d0f4a2d0)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /**************************************************************************
3  * Copyright (c) 2007-2011, Intel Corporation.
4  * All Rights Reserved.
5  *
6  **************************************************************************/
7 
8 #include <linux/fb.h>
9 
10 #include <drm/drm_crtc_helper.h>
11 #include <drm/drm_drv.h>
12 #include <drm/drm_fb_helper.h>
13 #include <drm/drm_framebuffer.h>
14 
15 #include "gem.h"
16 #include "psb_drv.h"
17 
18 /*
19  * VM area struct
20  */
21 
22 static vm_fault_t psb_fbdev_vm_fault(struct vm_fault *vmf)
23 {
24 	struct vm_area_struct *vma = vmf->vma;
25 	struct fb_info *info = vma->vm_private_data;
26 	unsigned long address = vmf->address - (vmf->pgoff << PAGE_SHIFT);
27 	unsigned long pfn = info->fix.smem_start >> PAGE_SHIFT;
28 	vm_fault_t err = VM_FAULT_SIGBUS;
29 	unsigned long page_num = vma_pages(vma);
30 	unsigned long i;
31 
32 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
33 
34 	for (i = 0; i < page_num; ++i) {
35 		err = vmf_insert_mixed(vma, address, pfn);
36 		if (unlikely(err & VM_FAULT_ERROR))
37 			break;
38 		address += PAGE_SIZE;
39 		++pfn;
40 	}
41 
42 	return err;
43 }
44 
45 static const struct vm_operations_struct psb_fbdev_vm_ops = {
46 	.fault	= psb_fbdev_vm_fault,
47 };
48 
49 /*
50  * struct fb_ops
51  */
52 
53 #define CMAP_TOHW(_val, _width) ((((_val) << (_width)) + 0x7FFF - (_val)) >> 16)
54 
55 static int psb_fbdev_fb_setcolreg(unsigned int regno,
56 				  unsigned int red, unsigned int green,
57 				  unsigned int blue, unsigned int transp,
58 				  struct fb_info *info)
59 {
60 	struct drm_fb_helper *fb_helper = info->par;
61 	struct drm_framebuffer *fb = fb_helper->fb;
62 	uint32_t v;
63 
64 	if (!fb)
65 		return -ENOMEM;
66 
67 	if (regno > 255)
68 		return 1;
69 
70 	red = CMAP_TOHW(red, info->var.red.length);
71 	blue = CMAP_TOHW(blue, info->var.blue.length);
72 	green = CMAP_TOHW(green, info->var.green.length);
73 	transp = CMAP_TOHW(transp, info->var.transp.length);
74 
75 	v = (red << info->var.red.offset) |
76 	    (green << info->var.green.offset) |
77 	    (blue << info->var.blue.offset) |
78 	    (transp << info->var.transp.offset);
79 
80 	if (regno < 16) {
81 		switch (fb->format->cpp[0] * 8) {
82 		case 16:
83 			((uint32_t *) info->pseudo_palette)[regno] = v;
84 			break;
85 		case 24:
86 		case 32:
87 			((uint32_t *) info->pseudo_palette)[regno] = v;
88 			break;
89 		}
90 	}
91 
92 	return 0;
93 }
94 
95 static int psb_fbdev_fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
96 {
97 	if (vma->vm_pgoff != 0)
98 		return -EINVAL;
99 	if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT))
100 		return -EINVAL;
101 
102 	/*
103 	 * If this is a GEM object then info->screen_base is the virtual
104 	 * kernel remapping of the object. FIXME: Review if this is
105 	 * suitable for our mmap work
106 	 */
107 	vma->vm_ops = &psb_fbdev_vm_ops;
108 	vma->vm_private_data = info;
109 	vm_flags_set(vma, VM_IO | VM_MIXEDMAP | VM_DONTEXPAND | VM_DONTDUMP);
110 
111 	return 0;
112 }
113 
114 static void psb_fbdev_fb_destroy(struct fb_info *info)
115 {
116 	struct drm_fb_helper *fb_helper = info->par;
117 	struct drm_framebuffer *fb = fb_helper->fb;
118 	struct drm_gem_object *obj = fb->obj[0];
119 
120 	drm_fb_helper_fini(fb_helper);
121 
122 	drm_framebuffer_unregister_private(fb);
123 	drm_framebuffer_cleanup(fb);
124 	kfree(fb);
125 
126 	drm_gem_object_put(obj);
127 
128 	drm_client_release(&fb_helper->client);
129 
130 	drm_fb_helper_unprepare(fb_helper);
131 	kfree(fb_helper);
132 }
133 
134 static const struct fb_ops psb_fbdev_fb_ops = {
135 	.owner = THIS_MODULE,
136 	__FB_DEFAULT_IOMEM_OPS_RDWR,
137 	DRM_FB_HELPER_DEFAULT_OPS,
138 	.fb_setcolreg = psb_fbdev_fb_setcolreg,
139 	__FB_DEFAULT_IOMEM_OPS_DRAW,
140 	.fb_mmap = psb_fbdev_fb_mmap,
141 	.fb_destroy = psb_fbdev_fb_destroy,
142 };
143 
144 static const struct drm_fb_helper_funcs psb_fbdev_fb_helper_funcs = {
145 };
146 
147 /*
148  * struct drm_driver
149  */
150 
151 int psb_fbdev_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
152 				 struct drm_fb_helper_surface_size *sizes)
153 {
154 	struct drm_device *dev = fb_helper->dev;
155 	struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
156 	struct pci_dev *pdev = to_pci_dev(dev->dev);
157 	struct fb_info *info;
158 	struct drm_framebuffer *fb;
159 	struct drm_mode_fb_cmd2 mode_cmd = { };
160 	int size;
161 	int ret;
162 	struct psb_gem_object *backing;
163 	struct drm_gem_object *obj;
164 	u32 bpp, depth;
165 
166 	/* No 24-bit packed mode */
167 	if (sizes->surface_bpp == 24) {
168 		sizes->surface_bpp = 32;
169 		sizes->surface_depth = 24;
170 	}
171 	bpp = sizes->surface_bpp;
172 	depth = sizes->surface_depth;
173 
174 	/*
175 	 * If the mode does not fit in 32 bit then switch to 16 bit to get
176 	 * a console on full resolution. The X mode setting server will
177 	 * allocate its own 32-bit GEM framebuffer.
178 	 */
179 	size = ALIGN(sizes->surface_width * DIV_ROUND_UP(bpp, 8), 64) *
180 		     sizes->surface_height;
181 	size = ALIGN(size, PAGE_SIZE);
182 
183 	if (size > dev_priv->vram_stolen_size) {
184 		sizes->surface_bpp = 16;
185 		sizes->surface_depth = 16;
186 	}
187 	bpp = sizes->surface_bpp;
188 	depth = sizes->surface_depth;
189 
190 	mode_cmd.width = sizes->surface_width;
191 	mode_cmd.height = sizes->surface_height;
192 	mode_cmd.pitches[0] = ALIGN(mode_cmd.width * DIV_ROUND_UP(bpp, 8), 64);
193 	mode_cmd.pixel_format = drm_mode_legacy_fb_format(bpp, depth);
194 
195 	size = mode_cmd.pitches[0] * mode_cmd.height;
196 	size = ALIGN(size, PAGE_SIZE);
197 
198 	/* Allocate the framebuffer in the GTT with stolen page backing */
199 	backing = psb_gem_create(dev, size, "fb", true, PAGE_SIZE);
200 	if (IS_ERR(backing))
201 		return PTR_ERR(backing);
202 	obj = &backing->base;
203 
204 	fb = psb_framebuffer_create(dev,
205 				    drm_get_format_info(dev, mode_cmd.pixel_format,
206 							mode_cmd.modifier[0]),
207 				    &mode_cmd, obj);
208 	if (IS_ERR(fb)) {
209 		ret = PTR_ERR(fb);
210 		goto err_drm_gem_object_put;
211 	}
212 
213 	fb_helper->funcs = &psb_fbdev_fb_helper_funcs;
214 	fb_helper->fb = fb;
215 
216 	info = drm_fb_helper_alloc_info(fb_helper);
217 	if (IS_ERR(info)) {
218 		ret = PTR_ERR(info);
219 		goto err_drm_framebuffer_unregister_private;
220 	}
221 
222 	info->fbops = &psb_fbdev_fb_ops;
223 
224 	/* Accessed stolen memory directly */
225 	info->screen_base = dev_priv->vram_addr + backing->offset;
226 	info->screen_size = size;
227 
228 	drm_fb_helper_fill_info(info, fb_helper, sizes);
229 
230 	info->fix.smem_start = dev_priv->stolen_base + backing->offset;
231 	info->fix.smem_len = size;
232 	info->fix.ywrapstep = 0;
233 	info->fix.ypanstep = 0;
234 	info->fix.mmio_start = pci_resource_start(pdev, 0);
235 	info->fix.mmio_len = pci_resource_len(pdev, 0);
236 
237 	fb_memset_io(info->screen_base, 0, info->screen_size);
238 
239 	/* Use default scratch pixmap (info->pixmap.flags = FB_PIXMAP_SYSTEM) */
240 
241 	dev_dbg(dev->dev, "allocated %dx%d fb\n", fb->width, fb->height);
242 
243 	return 0;
244 
245 err_drm_framebuffer_unregister_private:
246 	drm_framebuffer_unregister_private(fb);
247 	drm_framebuffer_cleanup(fb);
248 	kfree(fb);
249 err_drm_gem_object_put:
250 	drm_gem_object_put(obj);
251 	return ret;
252 }
253