xref: /openbmc/linux/drivers/gpu/drm/udl/udl_main.c (revision b830f94f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2012 Red Hat
4  *
5  * based in parts on udlfb.c:
6  * Copyright (C) 2009 Roberto De Ioris <roberto@unbit.it>
7  * Copyright (C) 2009 Jaya Kumar <jayakumar.lkml@gmail.com>
8  * Copyright (C) 2009 Bernie Thompson <bernie@plugable.com>
9  */
10 #include <drm/drmP.h>
11 #include <drm/drm_crtc_helper.h>
12 #include <drm/drm_probe_helper.h>
13 #include "udl_drv.h"
14 
15 /* -BULK_SIZE as per usb-skeleton. Can we get full page and avoid overhead? */
16 #define BULK_SIZE 512
17 
18 #define NR_USB_REQUEST_CHANNEL 0x12
19 
20 #define MAX_TRANSFER (PAGE_SIZE*16 - BULK_SIZE)
21 #define WRITES_IN_FLIGHT (4)
22 #define MAX_VENDOR_DESCRIPTOR_SIZE 256
23 
24 #define GET_URB_TIMEOUT	HZ
25 #define FREE_URB_TIMEOUT (HZ*2)
26 
27 static int udl_parse_vendor_descriptor(struct drm_device *dev,
28 				       struct usb_device *usbdev)
29 {
30 	struct udl_device *udl = to_udl(dev);
31 	char *desc;
32 	char *buf;
33 	char *desc_end;
34 
35 	u8 total_len = 0;
36 
37 	buf = kzalloc(MAX_VENDOR_DESCRIPTOR_SIZE, GFP_KERNEL);
38 	if (!buf)
39 		return false;
40 	desc = buf;
41 
42 	total_len = usb_get_descriptor(usbdev, 0x5f, /* vendor specific */
43 				    0, desc, MAX_VENDOR_DESCRIPTOR_SIZE);
44 	if (total_len > 5) {
45 		DRM_INFO("vendor descriptor length:%x data:%11ph\n",
46 			total_len, desc);
47 
48 		if ((desc[0] != total_len) || /* descriptor length */
49 		    (desc[1] != 0x5f) ||   /* vendor descriptor type */
50 		    (desc[2] != 0x01) ||   /* version (2 bytes) */
51 		    (desc[3] != 0x00) ||
52 		    (desc[4] != total_len - 2)) /* length after type */
53 			goto unrecognized;
54 
55 		desc_end = desc + total_len;
56 		desc += 5; /* the fixed header we've already parsed */
57 
58 		while (desc < desc_end) {
59 			u8 length;
60 			u16 key;
61 
62 			key = le16_to_cpu(*((u16 *) desc));
63 			desc += sizeof(u16);
64 			length = *desc;
65 			desc++;
66 
67 			switch (key) {
68 			case 0x0200: { /* max_area */
69 				u32 max_area;
70 				max_area = le32_to_cpu(*((u32 *)desc));
71 				DRM_DEBUG("DL chip limited to %d pixel modes\n",
72 					max_area);
73 				udl->sku_pixel_limit = max_area;
74 				break;
75 			}
76 			default:
77 				break;
78 			}
79 			desc += length;
80 		}
81 	}
82 
83 	goto success;
84 
85 unrecognized:
86 	/* allow udlfb to load for now even if firmware unrecognized */
87 	DRM_ERROR("Unrecognized vendor firmware descriptor\n");
88 
89 success:
90 	kfree(buf);
91 	return true;
92 }
93 
94 /*
95  * Need to ensure a channel is selected before submitting URBs
96  */
97 static int udl_select_std_channel(struct udl_device *udl)
98 {
99 	int ret;
100 	static const u8 set_def_chn[] = {0x57, 0xCD, 0xDC, 0xA7,
101 					 0x1C, 0x88, 0x5E, 0x15,
102 					 0x60, 0xFE, 0xC6, 0x97,
103 					 0x16, 0x3D, 0x47, 0xF2};
104 	void *sendbuf;
105 
106 	sendbuf = kmemdup(set_def_chn, sizeof(set_def_chn), GFP_KERNEL);
107 	if (!sendbuf)
108 		return -ENOMEM;
109 
110 	ret = usb_control_msg(udl->udev,
111 			      usb_sndctrlpipe(udl->udev, 0),
112 			      NR_USB_REQUEST_CHANNEL,
113 			      (USB_DIR_OUT | USB_TYPE_VENDOR), 0, 0,
114 			      sendbuf, sizeof(set_def_chn),
115 			      USB_CTRL_SET_TIMEOUT);
116 	kfree(sendbuf);
117 	return ret < 0 ? ret : 0;
118 }
119 
120 static void udl_release_urb_work(struct work_struct *work)
121 {
122 	struct urb_node *unode = container_of(work, struct urb_node,
123 					      release_urb_work.work);
124 
125 	up(&unode->dev->urbs.limit_sem);
126 }
127 
128 void udl_urb_completion(struct urb *urb)
129 {
130 	struct urb_node *unode = urb->context;
131 	struct udl_device *udl = unode->dev;
132 	unsigned long flags;
133 
134 	/* sync/async unlink faults aren't errors */
135 	if (urb->status) {
136 		if (!(urb->status == -ENOENT ||
137 		    urb->status == -ECONNRESET ||
138 		    urb->status == -ESHUTDOWN)) {
139 			DRM_ERROR("%s - nonzero write bulk status received: %d\n",
140 				__func__, urb->status);
141 			atomic_set(&udl->lost_pixels, 1);
142 		}
143 	}
144 
145 	urb->transfer_buffer_length = udl->urbs.size; /* reset to actual */
146 
147 	spin_lock_irqsave(&udl->urbs.lock, flags);
148 	list_add_tail(&unode->entry, &udl->urbs.list);
149 	udl->urbs.available++;
150 	spin_unlock_irqrestore(&udl->urbs.lock, flags);
151 
152 #if 0
153 	/*
154 	 * When using fb_defio, we deadlock if up() is called
155 	 * while another is waiting. So queue to another process.
156 	 */
157 	if (fb_defio)
158 		schedule_delayed_work(&unode->release_urb_work, 0);
159 	else
160 #endif
161 		up(&udl->urbs.limit_sem);
162 }
163 
164 static void udl_free_urb_list(struct drm_device *dev)
165 {
166 	struct udl_device *udl = to_udl(dev);
167 	int count = udl->urbs.count;
168 	struct list_head *node;
169 	struct urb_node *unode;
170 	struct urb *urb;
171 
172 	DRM_DEBUG("Waiting for completes and freeing all render urbs\n");
173 
174 	/* keep waiting and freeing, until we've got 'em all */
175 	while (count--) {
176 		down(&udl->urbs.limit_sem);
177 
178 		spin_lock_irq(&udl->urbs.lock);
179 
180 		node = udl->urbs.list.next; /* have reserved one with sem */
181 		list_del_init(node);
182 
183 		spin_unlock_irq(&udl->urbs.lock);
184 
185 		unode = list_entry(node, struct urb_node, entry);
186 		urb = unode->urb;
187 
188 		/* Free each separately allocated piece */
189 		usb_free_coherent(urb->dev, udl->urbs.size,
190 				  urb->transfer_buffer, urb->transfer_dma);
191 		usb_free_urb(urb);
192 		kfree(node);
193 	}
194 	udl->urbs.count = 0;
195 }
196 
197 static int udl_alloc_urb_list(struct drm_device *dev, int count, size_t size)
198 {
199 	struct udl_device *udl = to_udl(dev);
200 	struct urb *urb;
201 	struct urb_node *unode;
202 	char *buf;
203 	size_t wanted_size = count * size;
204 
205 	spin_lock_init(&udl->urbs.lock);
206 
207 retry:
208 	udl->urbs.size = size;
209 	INIT_LIST_HEAD(&udl->urbs.list);
210 
211 	sema_init(&udl->urbs.limit_sem, 0);
212 	udl->urbs.count = 0;
213 	udl->urbs.available = 0;
214 
215 	while (udl->urbs.count * size < wanted_size) {
216 		unode = kzalloc(sizeof(struct urb_node), GFP_KERNEL);
217 		if (!unode)
218 			break;
219 		unode->dev = udl;
220 
221 		INIT_DELAYED_WORK(&unode->release_urb_work,
222 			  udl_release_urb_work);
223 
224 		urb = usb_alloc_urb(0, GFP_KERNEL);
225 		if (!urb) {
226 			kfree(unode);
227 			break;
228 		}
229 		unode->urb = urb;
230 
231 		buf = usb_alloc_coherent(udl->udev, size, GFP_KERNEL,
232 					 &urb->transfer_dma);
233 		if (!buf) {
234 			kfree(unode);
235 			usb_free_urb(urb);
236 			if (size > PAGE_SIZE) {
237 				size /= 2;
238 				udl_free_urb_list(dev);
239 				goto retry;
240 			}
241 			break;
242 		}
243 
244 		/* urb->transfer_buffer_length set to actual before submit */
245 		usb_fill_bulk_urb(urb, udl->udev, usb_sndbulkpipe(udl->udev, 1),
246 			buf, size, udl_urb_completion, unode);
247 		urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
248 
249 		list_add_tail(&unode->entry, &udl->urbs.list);
250 
251 		up(&udl->urbs.limit_sem);
252 		udl->urbs.count++;
253 		udl->urbs.available++;
254 	}
255 
256 	DRM_DEBUG("allocated %d %d byte urbs\n", udl->urbs.count, (int) size);
257 
258 	return udl->urbs.count;
259 }
260 
261 struct urb *udl_get_urb(struct drm_device *dev)
262 {
263 	struct udl_device *udl = to_udl(dev);
264 	int ret = 0;
265 	struct list_head *entry;
266 	struct urb_node *unode;
267 	struct urb *urb = NULL;
268 
269 	/* Wait for an in-flight buffer to complete and get re-queued */
270 	ret = down_timeout(&udl->urbs.limit_sem, GET_URB_TIMEOUT);
271 	if (ret) {
272 		atomic_set(&udl->lost_pixels, 1);
273 		DRM_INFO("wait for urb interrupted: %x available: %d\n",
274 		       ret, udl->urbs.available);
275 		goto error;
276 	}
277 
278 	spin_lock_irq(&udl->urbs.lock);
279 
280 	BUG_ON(list_empty(&udl->urbs.list)); /* reserved one with limit_sem */
281 	entry = udl->urbs.list.next;
282 	list_del_init(entry);
283 	udl->urbs.available--;
284 
285 	spin_unlock_irq(&udl->urbs.lock);
286 
287 	unode = list_entry(entry, struct urb_node, entry);
288 	urb = unode->urb;
289 
290 error:
291 	return urb;
292 }
293 
294 int udl_submit_urb(struct drm_device *dev, struct urb *urb, size_t len)
295 {
296 	struct udl_device *udl = to_udl(dev);
297 	int ret;
298 
299 	BUG_ON(len > udl->urbs.size);
300 
301 	urb->transfer_buffer_length = len; /* set to actual payload len */
302 	ret = usb_submit_urb(urb, GFP_ATOMIC);
303 	if (ret) {
304 		udl_urb_completion(urb); /* because no one else will */
305 		atomic_set(&udl->lost_pixels, 1);
306 		DRM_ERROR("usb_submit_urb error %x\n", ret);
307 	}
308 	return ret;
309 }
310 
311 int udl_init(struct udl_device *udl)
312 {
313 	struct drm_device *dev = &udl->drm;
314 	int ret = -ENOMEM;
315 
316 	DRM_DEBUG("\n");
317 
318 	mutex_init(&udl->gem_lock);
319 
320 	if (!udl_parse_vendor_descriptor(dev, udl->udev)) {
321 		ret = -ENODEV;
322 		DRM_ERROR("firmware not recognized. Assume incompatible device\n");
323 		goto err;
324 	}
325 
326 	if (udl_select_std_channel(udl))
327 		DRM_ERROR("Selecting channel failed\n");
328 
329 	if (!udl_alloc_urb_list(dev, WRITES_IN_FLIGHT, MAX_TRANSFER)) {
330 		DRM_ERROR("udl_alloc_urb_list failed\n");
331 		goto err;
332 	}
333 
334 	DRM_DEBUG("\n");
335 	ret = udl_modeset_init(dev);
336 	if (ret)
337 		goto err;
338 
339 	ret = udl_fbdev_init(dev);
340 	if (ret)
341 		goto err;
342 
343 	drm_kms_helper_poll_init(dev);
344 
345 	return 0;
346 
347 err:
348 	if (udl->urbs.count)
349 		udl_free_urb_list(dev);
350 	DRM_ERROR("%d\n", ret);
351 	return ret;
352 }
353 
354 int udl_drop_usb(struct drm_device *dev)
355 {
356 	udl_free_urb_list(dev);
357 	return 0;
358 }
359 
360 void udl_fini(struct drm_device *dev)
361 {
362 	struct udl_device *udl = to_udl(dev);
363 
364 	drm_kms_helper_poll_fini(dev);
365 
366 	if (udl->urbs.count)
367 		udl_free_urb_list(dev);
368 
369 	udl_fbdev_cleanup(dev);
370 }
371