2 * Xen para-virtual frame buffer device
4 * Copyright (C) 2005-2006 Anthony Liguori <aliguori@us.ibm.com>
5 * Copyright (C) 2006-2008 Red Hat, Inc., Markus Armbruster <armbru@redhat.com>
7 * Based on linux/drivers/video/q40fb.c
9 * This file is subject to the terms and conditions of the GNU General Public
10 * License. See the file COPYING in the main directory of this archive for
17 * Switch to grant tables when they become capable of dealing with the
21 #include <linux/console.h>
22 #include <linux/kernel.h>
23 #include <linux/errno.h>
25 #include <linux/module.h>
26 #include <linux/vmalloc.h>
29 #include <asm/xen/hypervisor.h>
32 #include <xen/events.h>
34 #include <xen/interface/io/fbif.h>
35 #include <xen/interface/io/protocols.h>
36 #include <xen/xenbus.h>
40 struct fb_info *fb_info;
41 int x1, y1, x2, y2; /* dirty rectangle,
42 protected by dirty_lock */
43 spinlock_t dirty_lock;
46 struct xenfb_page *page;
48 int update_wanted; /* XENFB_TYPE_UPDATE wanted */
49 int feature_resize; /* XENFB_TYPE_RESIZE ok */
50 struct xenfb_resize resize; /* protected by resize_lock */
51 int resize_dpy; /* ditto */
52 spinlock_t resize_lock;
54 struct xenbus_device *xbdev;
57 #define XENFB_DEFAULT_FB_LEN (XENFB_WIDTH * XENFB_HEIGHT * XENFB_DEPTH / 8)
59 enum { KPARAM_MEM, KPARAM_WIDTH, KPARAM_HEIGHT, KPARAM_CNT };
60 static int video[KPARAM_CNT] = { 2, XENFB_WIDTH, XENFB_HEIGHT };
61 module_param_array(video, int, NULL, 0);
62 MODULE_PARM_DESC(video,
63 "Video memory size in MB, width, height in pixels (default 2,800,600)");
65 static void xenfb_make_preferred_console(void);
66 static int xenfb_remove(struct xenbus_device *);
67 static void xenfb_init_shared_page(struct xenfb_info *, struct fb_info *);
68 static int xenfb_connect_backend(struct xenbus_device *, struct xenfb_info *);
69 static void xenfb_disconnect_backend(struct xenfb_info *);
71 static void xenfb_send_event(struct xenfb_info *info,
72 union xenfb_out_event *event)
76 prod = info->page->out_prod;
77 /* caller ensures !xenfb_queue_full() */
78 mb(); /* ensure ring space available */
79 XENFB_OUT_RING_REF(info->page, prod) = *event;
80 wmb(); /* ensure ring contents visible */
81 info->page->out_prod = prod + 1;
83 notify_remote_via_irq(info->irq);
86 static void xenfb_do_update(struct xenfb_info *info,
87 int x, int y, int w, int h)
89 union xenfb_out_event event;
91 memset(&event, 0, sizeof(event));
92 event.type = XENFB_TYPE_UPDATE;
95 event.update.width = w;
96 event.update.height = h;
98 /* caller ensures !xenfb_queue_full() */
99 xenfb_send_event(info, &event);
102 static void xenfb_do_resize(struct xenfb_info *info)
104 union xenfb_out_event event;
106 memset(&event, 0, sizeof(event));
107 event.resize = info->resize;
109 /* caller ensures !xenfb_queue_full() */
110 xenfb_send_event(info, &event);
113 static int xenfb_queue_full(struct xenfb_info *info)
117 prod = info->page->out_prod;
118 cons = info->page->out_cons;
119 return prod - cons == XENFB_OUT_RING_LEN;
122 static void xenfb_handle_resize_dpy(struct xenfb_info *info)
126 spin_lock_irqsave(&info->resize_lock, flags);
127 if (info->resize_dpy) {
128 if (!xenfb_queue_full(info)) {
129 info->resize_dpy = 0;
130 xenfb_do_resize(info);
133 spin_unlock_irqrestore(&info->resize_lock, flags);
136 static void xenfb_refresh(struct xenfb_info *info,
137 int x1, int y1, int w, int h)
143 xenfb_handle_resize_dpy(info);
145 if (!info->update_wanted)
148 spin_lock_irqsave(&info->dirty_lock, flags);
150 /* Combine with dirty rectangle: */
160 if (xenfb_queue_full(info)) {
161 /* Can't send right now, stash it in the dirty rectangle */
166 spin_unlock_irqrestore(&info->dirty_lock, flags);
170 /* Clear dirty rectangle: */
171 info->x1 = info->y1 = INT_MAX;
172 info->x2 = info->y2 = 0;
174 spin_unlock_irqrestore(&info->dirty_lock, flags);
176 if (x1 <= x2 && y1 <= y2)
177 xenfb_do_update(info, x1, y1, x2 - x1 + 1, y2 - y1 + 1);
180 static void xenfb_deferred_io(struct fb_info *fb_info,
181 struct list_head *pagelist)
183 struct xenfb_info *info = fb_info->par;
185 unsigned long beg, end;
186 int y1, y2, miny, maxy;
190 list_for_each_entry(page, pagelist, lru) {
191 beg = page->index << PAGE_SHIFT;
192 end = beg + PAGE_SIZE - 1;
193 y1 = beg / fb_info->fix.line_length;
194 y2 = end / fb_info->fix.line_length;
195 if (y2 >= fb_info->var.yres)
196 y2 = fb_info->var.yres - 1;
202 xenfb_refresh(info, 0, miny, fb_info->var.xres, maxy - miny + 1);
205 static struct fb_deferred_io xenfb_defio = {
207 .deferred_io = xenfb_deferred_io,
210 static int xenfb_setcolreg(unsigned regno, unsigned red, unsigned green,
211 unsigned blue, unsigned transp,
212 struct fb_info *info)
216 if (regno > info->cmap.len)
219 #define CNVT_TOHW(val, width) ((((val)<<(width))+0x7FFF-(val))>>16)
220 red = CNVT_TOHW(red, info->var.red.length);
221 green = CNVT_TOHW(green, info->var.green.length);
222 blue = CNVT_TOHW(blue, info->var.blue.length);
223 transp = CNVT_TOHW(transp, info->var.transp.length);
226 v = (red << info->var.red.offset) |
227 (green << info->var.green.offset) |
228 (blue << info->var.blue.offset);
230 switch (info->var.bits_per_pixel) {
234 ((u32 *)info->pseudo_palette)[regno] = v;
241 static void xenfb_fillrect(struct fb_info *p, const struct fb_fillrect *rect)
243 struct xenfb_info *info = p->par;
245 sys_fillrect(p, rect);
246 xenfb_refresh(info, rect->dx, rect->dy, rect->width, rect->height);
249 static void xenfb_imageblit(struct fb_info *p, const struct fb_image *image)
251 struct xenfb_info *info = p->par;
253 sys_imageblit(p, image);
254 xenfb_refresh(info, image->dx, image->dy, image->width, image->height);
257 static void xenfb_copyarea(struct fb_info *p, const struct fb_copyarea *area)
259 struct xenfb_info *info = p->par;
261 sys_copyarea(p, area);
262 xenfb_refresh(info, area->dx, area->dy, area->width, area->height);
265 static ssize_t xenfb_write(struct fb_info *p, const char __user *buf,
266 size_t count, loff_t *ppos)
268 struct xenfb_info *info = p->par;
271 res = fb_sys_write(p, buf, count, ppos);
272 xenfb_refresh(info, 0, 0, info->page->width, info->page->height);
277 xenfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
279 struct xenfb_info *xenfb_info;
280 int required_mem_len;
282 xenfb_info = info->par;
284 if (!xenfb_info->feature_resize) {
285 if (var->xres == video[KPARAM_WIDTH] &&
286 var->yres == video[KPARAM_HEIGHT] &&
287 var->bits_per_pixel == xenfb_info->page->depth) {
293 /* Can't resize past initial width and height */
294 if (var->xres > video[KPARAM_WIDTH] || var->yres > video[KPARAM_HEIGHT])
297 required_mem_len = var->xres * var->yres * xenfb_info->page->depth / 8;
298 if (var->bits_per_pixel == xenfb_info->page->depth &&
299 var->xres <= info->fix.line_length / (XENFB_DEPTH / 8) &&
300 required_mem_len <= info->fix.smem_len) {
301 var->xres_virtual = var->xres;
302 var->yres_virtual = var->yres;
308 static int xenfb_set_par(struct fb_info *info)
310 struct xenfb_info *xenfb_info;
313 xenfb_info = info->par;
315 spin_lock_irqsave(&xenfb_info->resize_lock, flags);
316 xenfb_info->resize.type = XENFB_TYPE_RESIZE;
317 xenfb_info->resize.width = info->var.xres;
318 xenfb_info->resize.height = info->var.yres;
319 xenfb_info->resize.stride = info->fix.line_length;
320 xenfb_info->resize.depth = info->var.bits_per_pixel;
321 xenfb_info->resize.offset = 0;
322 xenfb_info->resize_dpy = 1;
323 spin_unlock_irqrestore(&xenfb_info->resize_lock, flags);
327 static struct fb_ops xenfb_fb_ops = {
328 .owner = THIS_MODULE,
329 .fb_read = fb_sys_read,
330 .fb_write = xenfb_write,
331 .fb_setcolreg = xenfb_setcolreg,
332 .fb_fillrect = xenfb_fillrect,
333 .fb_copyarea = xenfb_copyarea,
334 .fb_imageblit = xenfb_imageblit,
335 .fb_check_var = xenfb_check_var,
336 .fb_set_par = xenfb_set_par,
339 static irqreturn_t xenfb_event_handler(int rq, void *dev_id)
342 * No in events recognized, simply ignore them all.
343 * If you need to recognize some, see xen-kbdfront's
344 * input_handler() for how to do that.
346 struct xenfb_info *info = dev_id;
347 struct xenfb_page *page = info->page;
349 if (page->in_cons != page->in_prod) {
350 info->page->in_cons = info->page->in_prod;
351 notify_remote_via_irq(info->irq);
354 /* Flush dirty rectangle: */
355 xenfb_refresh(info, INT_MAX, INT_MAX, -INT_MAX, -INT_MAX);
360 static int __devinit xenfb_probe(struct xenbus_device *dev,
361 const struct xenbus_device_id *id)
363 struct xenfb_info *info;
364 struct fb_info *fb_info;
369 info = kzalloc(sizeof(*info), GFP_KERNEL);
371 xenbus_dev_fatal(dev, -ENOMEM, "allocating info structure");
375 /* Limit kernel param videoram amount to what is in xenstore */
376 if (xenbus_scanf(XBT_NIL, dev->otherend, "videoram", "%d", &val) == 1) {
377 if (val < video[KPARAM_MEM])
378 video[KPARAM_MEM] = val;
381 /* If requested res does not fit in available memory, use default */
382 fb_size = video[KPARAM_MEM] * 1024 * 1024;
383 if (video[KPARAM_WIDTH] * video[KPARAM_HEIGHT] * XENFB_DEPTH / 8
385 video[KPARAM_WIDTH] = XENFB_WIDTH;
386 video[KPARAM_HEIGHT] = XENFB_HEIGHT;
387 fb_size = XENFB_DEFAULT_FB_LEN;
390 dev_set_drvdata(&dev->dev, info);
393 info->x1 = info->y1 = INT_MAX;
394 spin_lock_init(&info->dirty_lock);
395 spin_lock_init(&info->resize_lock);
397 info->fb = vmalloc(fb_size);
398 if (info->fb == NULL)
400 memset(info->fb, 0, fb_size);
402 info->nr_pages = (fb_size + PAGE_SIZE - 1) >> PAGE_SHIFT;
404 info->mfns = vmalloc(sizeof(unsigned long) * info->nr_pages);
408 /* set up shared page */
409 info->page = (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
413 /* abusing framebuffer_alloc() to allocate pseudo_palette */
414 fb_info = framebuffer_alloc(sizeof(u32) * 256, NULL);
418 /* complete the abuse: */
419 fb_info->pseudo_palette = fb_info->par;
422 fb_info->screen_base = info->fb;
424 fb_info->fbops = &xenfb_fb_ops;
425 fb_info->var.xres_virtual = fb_info->var.xres = video[KPARAM_WIDTH];
426 fb_info->var.yres_virtual = fb_info->var.yres = video[KPARAM_HEIGHT];
427 fb_info->var.bits_per_pixel = XENFB_DEPTH;
429 fb_info->var.red = (struct fb_bitfield){16, 8, 0};
430 fb_info->var.green = (struct fb_bitfield){8, 8, 0};
431 fb_info->var.blue = (struct fb_bitfield){0, 8, 0};
433 fb_info->var.activate = FB_ACTIVATE_NOW;
434 fb_info->var.height = -1;
435 fb_info->var.width = -1;
436 fb_info->var.vmode = FB_VMODE_NONINTERLACED;
438 fb_info->fix.visual = FB_VISUAL_TRUECOLOR;
439 fb_info->fix.line_length = fb_info->var.xres * XENFB_DEPTH / 8;
440 fb_info->fix.smem_start = 0;
441 fb_info->fix.smem_len = fb_size;
442 strcpy(fb_info->fix.id, "xen");
443 fb_info->fix.type = FB_TYPE_PACKED_PIXELS;
444 fb_info->fix.accel = FB_ACCEL_NONE;
446 fb_info->flags = FBINFO_FLAG_DEFAULT | FBINFO_VIRTFB;
448 ret = fb_alloc_cmap(&fb_info->cmap, 256, 0);
450 framebuffer_release(fb_info);
451 xenbus_dev_fatal(dev, ret, "fb_alloc_cmap");
455 fb_info->fbdefio = &xenfb_defio;
456 fb_deferred_io_init(fb_info);
458 xenfb_init_shared_page(info, fb_info);
460 ret = xenfb_connect_backend(dev, info);
464 ret = register_framebuffer(fb_info);
466 fb_deferred_io_cleanup(fb_info);
467 fb_dealloc_cmap(&fb_info->cmap);
468 framebuffer_release(fb_info);
469 xenbus_dev_fatal(dev, ret, "register_framebuffer");
472 info->fb_info = fb_info;
474 xenfb_make_preferred_console();
479 xenbus_dev_fatal(dev, ret, "allocating device memory");
485 static __devinit void
486 xenfb_make_preferred_console(void)
490 if (console_set_on_cmdline)
493 acquire_console_sem();
494 for (c = console_drivers; c; c = c->next) {
495 if (!strcmp(c->name, "tty") && c->index == 0)
498 release_console_sem();
500 unregister_console(c);
501 c->flags |= CON_CONSDEV;
502 c->flags &= ~CON_PRINTBUFFER; /* don't print again */
507 static int xenfb_resume(struct xenbus_device *dev)
509 struct xenfb_info *info = dev_get_drvdata(&dev->dev);
511 xenfb_disconnect_backend(info);
512 xenfb_init_shared_page(info, info->fb_info);
513 return xenfb_connect_backend(dev, info);
516 static int xenfb_remove(struct xenbus_device *dev)
518 struct xenfb_info *info = dev_get_drvdata(&dev->dev);
520 xenfb_disconnect_backend(info);
522 fb_deferred_io_cleanup(info->fb_info);
523 unregister_framebuffer(info->fb_info);
524 fb_dealloc_cmap(&info->fb_info->cmap);
525 framebuffer_release(info->fb_info);
527 free_page((unsigned long)info->page);
535 static unsigned long vmalloc_to_mfn(void *address)
537 return pfn_to_mfn(vmalloc_to_pfn(address));
540 static void xenfb_init_shared_page(struct xenfb_info *info,
541 struct fb_info *fb_info)
544 int epd = PAGE_SIZE / sizeof(info->mfns[0]);
546 for (i = 0; i < info->nr_pages; i++)
547 info->mfns[i] = vmalloc_to_mfn(info->fb + i * PAGE_SIZE);
549 for (i = 0; i * epd < info->nr_pages; i++)
550 info->page->pd[i] = vmalloc_to_mfn(&info->mfns[i * epd]);
552 info->page->width = fb_info->var.xres;
553 info->page->height = fb_info->var.yres;
554 info->page->depth = fb_info->var.bits_per_pixel;
555 info->page->line_length = fb_info->fix.line_length;
556 info->page->mem_length = fb_info->fix.smem_len;
557 info->page->in_cons = info->page->in_prod = 0;
558 info->page->out_cons = info->page->out_prod = 0;
561 static int xenfb_connect_backend(struct xenbus_device *dev,
562 struct xenfb_info *info)
565 struct xenbus_transaction xbt;
567 ret = xenbus_alloc_evtchn(dev, &evtchn);
570 ret = bind_evtchn_to_irqhandler(evtchn, xenfb_event_handler,
571 0, dev->devicetype, info);
573 xenbus_free_evtchn(dev, evtchn);
574 xenbus_dev_fatal(dev, ret, "bind_evtchn_to_irqhandler");
580 ret = xenbus_transaction_start(&xbt);
582 xenbus_dev_fatal(dev, ret, "starting transaction");
585 ret = xenbus_printf(xbt, dev->nodename, "page-ref", "%lu",
586 virt_to_mfn(info->page));
589 ret = xenbus_printf(xbt, dev->nodename, "event-channel", "%u",
593 ret = xenbus_printf(xbt, dev->nodename, "protocol", "%s",
594 XEN_IO_PROTO_ABI_NATIVE);
597 ret = xenbus_printf(xbt, dev->nodename, "feature-update", "1");
600 ret = xenbus_transaction_end(xbt, 0);
604 xenbus_dev_fatal(dev, ret, "completing transaction");
608 xenbus_switch_state(dev, XenbusStateInitialised);
612 xenbus_transaction_end(xbt, 1);
613 xenbus_dev_fatal(dev, ret, "writing xenstore");
617 static void xenfb_disconnect_backend(struct xenfb_info *info)
620 unbind_from_irqhandler(info->irq, info);
624 static void xenfb_backend_changed(struct xenbus_device *dev,
625 enum xenbus_state backend_state)
627 struct xenfb_info *info = dev_get_drvdata(&dev->dev);
630 switch (backend_state) {
631 case XenbusStateInitialising:
632 case XenbusStateInitialised:
633 case XenbusStateUnknown:
634 case XenbusStateClosed:
637 case XenbusStateInitWait:
639 xenbus_switch_state(dev, XenbusStateConnected);
642 case XenbusStateConnected:
644 * Work around xenbus race condition: If backend goes
645 * through InitWait to Connected fast enough, we can
646 * get Connected twice here.
648 if (dev->state != XenbusStateConnected)
649 goto InitWait; /* no InitWait seen yet, fudge it */
651 if (xenbus_scanf(XBT_NIL, info->xbdev->otherend,
652 "request-update", "%d", &val) < 0)
655 info->update_wanted = 1;
657 if (xenbus_scanf(XBT_NIL, dev->otherend,
658 "feature-resize", "%d", &val) < 0)
660 info->feature_resize = val;
663 case XenbusStateClosing:
664 xenbus_frontend_closed(dev);
669 static struct xenbus_device_id xenfb_ids[] = {
674 static struct xenbus_driver xenfb_driver = {
676 .owner = THIS_MODULE,
678 .probe = xenfb_probe,
679 .remove = xenfb_remove,
680 .resume = xenfb_resume,
681 .otherend_changed = xenfb_backend_changed,
684 static int __init xenfb_init(void)
689 /* Nothing to do if running in dom0. */
690 if (xen_initial_domain())
693 return xenbus_register_frontend(&xenfb_driver);
696 static void __exit xenfb_cleanup(void)
698 xenbus_unregister_driver(&xenfb_driver);
701 module_init(xenfb_init);
702 module_exit(xenfb_cleanup);
704 MODULE_DESCRIPTION("Xen virtual framebuffer device frontend");
705 MODULE_LICENSE("GPL");
706 MODULE_ALIAS("xen:vfb");