xref: /linux/drivers/gpu/drm/gma500/fbdev.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
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 #include <linux/pfn_t.h>
10 
11 #include <drm/drm_crtc_helper.h>
12 #include <drm/drm_drv.h>
13 #include <drm/drm_fb_helper.h>
14 #include <drm/drm_framebuffer.h>
15 
16 #include "gem.h"
17 #include "psb_drv.h"
18 
19 /*
20  * VM area struct
21  */
22 
23 static vm_fault_t psb_fbdev_vm_fault(struct vm_fault *vmf)
24 {
25 	struct vm_area_struct *vma = vmf->vma;
26 	struct fb_info *info = vma->vm_private_data;
27 	unsigned long address = vmf->address - (vmf->pgoff << PAGE_SHIFT);
28 	unsigned long pfn = info->fix.smem_start >> PAGE_SHIFT;
29 	vm_fault_t err = VM_FAULT_SIGBUS;
30 	unsigned long page_num = vma_pages(vma);
31 	unsigned long i;
32 
33 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
34 
35 	for (i = 0; i < page_num; ++i) {
36 		err = vmf_insert_mixed(vma, address, __pfn_to_pfn_t(pfn, PFN_DEV));
37 		if (unlikely(err & VM_FAULT_ERROR))
38 			break;
39 		address += PAGE_SIZE;
40 		++pfn;
41 	}
42 
43 	return err;
44 }
45 
46 static const struct vm_operations_struct psb_fbdev_vm_ops = {
47 	.fault	= psb_fbdev_vm_fault,
48 };
49 
50 /*
51  * struct fb_ops
52  */
53 
54 #define CMAP_TOHW(_val, _width) ((((_val) << (_width)) + 0x7FFF - (_val)) >> 16)
55 
56 static int psb_fbdev_fb_setcolreg(unsigned int regno,
57 				  unsigned int red, unsigned int green,
58 				  unsigned int blue, unsigned int transp,
59 				  struct fb_info *info)
60 {
61 	struct drm_fb_helper *fb_helper = info->par;
62 	struct drm_framebuffer *fb = fb_helper->fb;
63 	uint32_t v;
64 
65 	if (!fb)
66 		return -ENOMEM;
67 
68 	if (regno > 255)
69 		return 1;
70 
71 	red = CMAP_TOHW(red, info->var.red.length);
72 	blue = CMAP_TOHW(blue, info->var.blue.length);
73 	green = CMAP_TOHW(green, info->var.green.length);
74 	transp = CMAP_TOHW(transp, info->var.transp.length);
75 
76 	v = (red << info->var.red.offset) |
77 	    (green << info->var.green.offset) |
78 	    (blue << info->var.blue.offset) |
79 	    (transp << info->var.transp.offset);
80 
81 	if (regno < 16) {
82 		switch (fb->format->cpp[0] * 8) {
83 		case 16:
84 			((uint32_t *) info->pseudo_palette)[regno] = v;
85 			break;
86 		case 24:
87 		case 32:
88 			((uint32_t *) info->pseudo_palette)[regno] = v;
89 			break;
90 		}
91 	}
92 
93 	return 0;
94 }
95 
96 static int psb_fbdev_fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
97 {
98 	if (vma->vm_pgoff != 0)
99 		return -EINVAL;
100 	if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT))
101 		return -EINVAL;
102 
103 	/*
104 	 * If this is a GEM object then info->screen_base is the virtual
105 	 * kernel remapping of the object. FIXME: Review if this is
106 	 * suitable for our mmap work
107 	 */
108 	vma->vm_ops = &psb_fbdev_vm_ops;
109 	vma->vm_private_data = info;
110 	vm_flags_set(vma, VM_IO | VM_MIXEDMAP | VM_DONTEXPAND | VM_DONTDUMP);
111 
112 	return 0;
113 }
114 
115 static void psb_fbdev_fb_destroy(struct fb_info *info)
116 {
117 	struct drm_fb_helper *fb_helper = info->par;
118 	struct drm_framebuffer *fb = fb_helper->fb;
119 	struct drm_gem_object *obj = fb->obj[0];
120 
121 	drm_fb_helper_fini(fb_helper);
122 
123 	drm_framebuffer_unregister_private(fb);
124 	fb->obj[0] = NULL;
125 	drm_framebuffer_cleanup(fb);
126 	kfree(fb);
127 
128 	drm_gem_object_put(obj);
129 
130 	drm_client_release(&fb_helper->client);
131 
132 	drm_fb_helper_unprepare(fb_helper);
133 	kfree(fb_helper);
134 }
135 
136 static const struct fb_ops psb_fbdev_fb_ops = {
137 	.owner = THIS_MODULE,
138 	__FB_DEFAULT_IOMEM_OPS_RDWR,
139 	DRM_FB_HELPER_DEFAULT_OPS,
140 	.fb_setcolreg = psb_fbdev_fb_setcolreg,
141 	__FB_DEFAULT_IOMEM_OPS_DRAW,
142 	.fb_mmap = psb_fbdev_fb_mmap,
143 	.fb_destroy = psb_fbdev_fb_destroy,
144 };
145 
146 static const struct drm_fb_helper_funcs psb_fbdev_fb_helper_funcs = {
147 };
148 
149 /*
150  * struct drm_driver
151  */
152 
153 int psb_fbdev_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
154 				 struct drm_fb_helper_surface_size *sizes)
155 {
156 	struct drm_device *dev = fb_helper->dev;
157 	struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
158 	struct pci_dev *pdev = to_pci_dev(dev->dev);
159 	struct fb_info *info;
160 	struct drm_framebuffer *fb;
161 	struct drm_mode_fb_cmd2 mode_cmd = { };
162 	int size;
163 	int ret;
164 	struct psb_gem_object *backing;
165 	struct drm_gem_object *obj;
166 	u32 bpp, depth;
167 
168 	/* No 24-bit packed mode */
169 	if (sizes->surface_bpp == 24) {
170 		sizes->surface_bpp = 32;
171 		sizes->surface_depth = 24;
172 	}
173 	bpp = sizes->surface_bpp;
174 	depth = sizes->surface_depth;
175 
176 	/*
177 	 * If the mode does not fit in 32 bit then switch to 16 bit to get
178 	 * a console on full resolution. The X mode setting server will
179 	 * allocate its own 32-bit GEM framebuffer.
180 	 */
181 	size = ALIGN(sizes->surface_width * DIV_ROUND_UP(bpp, 8), 64) *
182 		     sizes->surface_height;
183 	size = ALIGN(size, PAGE_SIZE);
184 
185 	if (size > dev_priv->vram_stolen_size) {
186 		sizes->surface_bpp = 16;
187 		sizes->surface_depth = 16;
188 	}
189 	bpp = sizes->surface_bpp;
190 	depth = sizes->surface_depth;
191 
192 	mode_cmd.width = sizes->surface_width;
193 	mode_cmd.height = sizes->surface_height;
194 	mode_cmd.pitches[0] = ALIGN(mode_cmd.width * DIV_ROUND_UP(bpp, 8), 64);
195 	mode_cmd.pixel_format = drm_mode_legacy_fb_format(bpp, depth);
196 
197 	size = mode_cmd.pitches[0] * mode_cmd.height;
198 	size = ALIGN(size, PAGE_SIZE);
199 
200 	/* Allocate the framebuffer in the GTT with stolen page backing */
201 	backing = psb_gem_create(dev, size, "fb", true, PAGE_SIZE);
202 	if (IS_ERR(backing))
203 		return PTR_ERR(backing);
204 	obj = &backing->base;
205 
206 	fb = psb_framebuffer_create(dev, &mode_cmd, obj);
207 	if (IS_ERR(fb)) {
208 		ret = PTR_ERR(fb);
209 		goto err_drm_gem_object_put;
210 	}
211 
212 	fb_helper->funcs = &psb_fbdev_fb_helper_funcs;
213 	fb_helper->fb = fb;
214 
215 	info = drm_fb_helper_alloc_info(fb_helper);
216 	if (IS_ERR(info)) {
217 		ret = PTR_ERR(info);
218 		goto err_drm_framebuffer_unregister_private;
219 	}
220 
221 	info->fbops = &psb_fbdev_fb_ops;
222 
223 	/* Accessed stolen memory directly */
224 	info->screen_base = dev_priv->vram_addr + backing->offset;
225 	info->screen_size = size;
226 
227 	drm_fb_helper_fill_info(info, fb_helper, sizes);
228 
229 	info->fix.smem_start = dev_priv->stolen_base + backing->offset;
230 	info->fix.smem_len = size;
231 	info->fix.ywrapstep = 0;
232 	info->fix.ypanstep = 0;
233 	info->fix.mmio_start = pci_resource_start(pdev, 0);
234 	info->fix.mmio_len = pci_resource_len(pdev, 0);
235 
236 	fb_memset_io(info->screen_base, 0, info->screen_size);
237 
238 	/* Use default scratch pixmap (info->pixmap.flags = FB_PIXMAP_SYSTEM) */
239 
240 	dev_dbg(dev->dev, "allocated %dx%d fb\n", fb->width, fb->height);
241 
242 	return 0;
243 
244 err_drm_framebuffer_unregister_private:
245 	drm_framebuffer_unregister_private(fb);
246 	fb->obj[0] = NULL;
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