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/slab.h>
27 #include <linux/vmalloc.h>
30 #include <asm/xen/hypervisor.h>
33 #include <xen/events.h>
35 #include <xen/interface/io/fbif.h>
36 #include <xen/interface/io/protocols.h>
37 #include <xen/xenbus.h>
41 struct fb_info *fb_info;
42 int x1, y1, x2, y2; /* dirty rectangle,
43 protected by dirty_lock */
44 spinlock_t dirty_lock;
47 struct xenfb_page *page;
49 int update_wanted; /* XENFB_TYPE_UPDATE wanted */
50 int feature_resize; /* XENFB_TYPE_RESIZE ok */
51 struct xenfb_resize resize; /* protected by resize_lock */
52 int resize_dpy; /* ditto */
53 spinlock_t resize_lock;
55 struct xenbus_device *xbdev;
58 #define XENFB_DEFAULT_FB_LEN (XENFB_WIDTH * XENFB_HEIGHT * XENFB_DEPTH / 8)
60 enum { KPARAM_MEM, KPARAM_WIDTH, KPARAM_HEIGHT, KPARAM_CNT };
61 static int video[KPARAM_CNT] = { 2, XENFB_WIDTH, XENFB_HEIGHT };
62 module_param_array(video, int, NULL, 0);
63 MODULE_PARM_DESC(video,
64 "Video memory size in MB, width, height in pixels (default 2,800,600)");
66 static void xenfb_make_preferred_console(void);
67 static int xenfb_remove(struct xenbus_device *);
68 static void xenfb_init_shared_page(struct xenfb_info *, struct fb_info *);
69 static int xenfb_connect_backend(struct xenbus_device *, struct xenfb_info *);
70 static void xenfb_disconnect_backend(struct xenfb_info *);
72 static void xenfb_send_event(struct xenfb_info *info,
73 union xenfb_out_event *event)
77 prod = info->page->out_prod;
78 /* caller ensures !xenfb_queue_full() */
79 mb(); /* ensure ring space available */
80 XENFB_OUT_RING_REF(info->page, prod) = *event;
81 wmb(); /* ensure ring contents visible */
82 info->page->out_prod = prod + 1;
84 notify_remote_via_irq(info->irq);
87 static void xenfb_do_update(struct xenfb_info *info,
88 int x, int y, int w, int h)
90 union xenfb_out_event event;
92 memset(&event, 0, sizeof(event));
93 event.type = XENFB_TYPE_UPDATE;
96 event.update.width = w;
97 event.update.height = h;
99 /* caller ensures !xenfb_queue_full() */
100 xenfb_send_event(info, &event);
103 static void xenfb_do_resize(struct xenfb_info *info)
105 union xenfb_out_event event;
107 memset(&event, 0, sizeof(event));
108 event.resize = info->resize;
110 /* caller ensures !xenfb_queue_full() */
111 xenfb_send_event(info, &event);
114 static int xenfb_queue_full(struct xenfb_info *info)
118 prod = info->page->out_prod;
119 cons = info->page->out_cons;
120 return prod - cons == XENFB_OUT_RING_LEN;
123 static void xenfb_handle_resize_dpy(struct xenfb_info *info)
127 spin_lock_irqsave(&info->resize_lock, flags);
128 if (info->resize_dpy) {
129 if (!xenfb_queue_full(info)) {
130 info->resize_dpy = 0;
131 xenfb_do_resize(info);
134 spin_unlock_irqrestore(&info->resize_lock, flags);
137 static void xenfb_refresh(struct xenfb_info *info,
138 int x1, int y1, int w, int h)
144 xenfb_handle_resize_dpy(info);
146 if (!info->update_wanted)
149 spin_lock_irqsave(&info->dirty_lock, flags);
151 /* Combine with dirty rectangle: */
161 if (xenfb_queue_full(info)) {
162 /* Can't send right now, stash it in the dirty rectangle */
167 spin_unlock_irqrestore(&info->dirty_lock, flags);
171 /* Clear dirty rectangle: */
172 info->x1 = info->y1 = INT_MAX;
173 info->x2 = info->y2 = 0;
175 spin_unlock_irqrestore(&info->dirty_lock, flags);
177 if (x1 <= x2 && y1 <= y2)
178 xenfb_do_update(info, x1, y1, x2 - x1 + 1, y2 - y1 + 1);
181 static void xenfb_deferred_io(struct fb_info *fb_info,
182 struct list_head *pagelist)
184 struct xenfb_info *info = fb_info->par;
186 unsigned long beg, end;
187 int y1, y2, miny, maxy;
191 list_for_each_entry(page, pagelist, lru) {
192 beg = page->index << PAGE_SHIFT;
193 end = beg + PAGE_SIZE - 1;
194 y1 = beg / fb_info->fix.line_length;
195 y2 = end / fb_info->fix.line_length;
196 if (y2 >= fb_info->var.yres)
197 y2 = fb_info->var.yres - 1;
203 xenfb_refresh(info, 0, miny, fb_info->var.xres, maxy - miny + 1);
206 static struct fb_deferred_io xenfb_defio = {
208 .deferred_io = xenfb_deferred_io,
211 static int xenfb_setcolreg(unsigned regno, unsigned red, unsigned green,
212 unsigned blue, unsigned transp,
213 struct fb_info *info)
217 if (regno > info->cmap.len)
220 #define CNVT_TOHW(val, width) ((((val)<<(width))+0x7FFF-(val))>>16)
221 red = CNVT_TOHW(red, info->var.red.length);
222 green = CNVT_TOHW(green, info->var.green.length);
223 blue = CNVT_TOHW(blue, info->var.blue.length);
224 transp = CNVT_TOHW(transp, info->var.transp.length);
227 v = (red << info->var.red.offset) |
228 (green << info->var.green.offset) |
229 (blue << info->var.blue.offset);
231 switch (info->var.bits_per_pixel) {
235 ((u32 *)info->pseudo_palette)[regno] = v;
242 static void xenfb_fillrect(struct fb_info *p, const struct fb_fillrect *rect)
244 struct xenfb_info *info = p->par;
246 sys_fillrect(p, rect);
247 xenfb_refresh(info, rect->dx, rect->dy, rect->width, rect->height);
250 static void xenfb_imageblit(struct fb_info *p, const struct fb_image *image)
252 struct xenfb_info *info = p->par;
254 sys_imageblit(p, image);
255 xenfb_refresh(info, image->dx, image->dy, image->width, image->height);
258 static void xenfb_copyarea(struct fb_info *p, const struct fb_copyarea *area)
260 struct xenfb_info *info = p->par;
262 sys_copyarea(p, area);
263 xenfb_refresh(info, area->dx, area->dy, area->width, area->height);
266 static ssize_t xenfb_write(struct fb_info *p, const char __user *buf,
267 size_t count, loff_t *ppos)
269 struct xenfb_info *info = p->par;
272 res = fb_sys_write(p, buf, count, ppos);
273 xenfb_refresh(info, 0, 0, info->page->width, info->page->height);
278 xenfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
280 struct xenfb_info *xenfb_info;
281 int required_mem_len;
283 xenfb_info = info->par;
285 if (!xenfb_info->feature_resize) {
286 if (var->xres == video[KPARAM_WIDTH] &&
287 var->yres == video[KPARAM_HEIGHT] &&
288 var->bits_per_pixel == xenfb_info->page->depth) {
294 /* Can't resize past initial width and height */
295 if (var->xres > video[KPARAM_WIDTH] || var->yres > video[KPARAM_HEIGHT])
298 required_mem_len = var->xres * var->yres * xenfb_info->page->depth / 8;
299 if (var->bits_per_pixel == xenfb_info->page->depth &&
300 var->xres <= info->fix.line_length / (XENFB_DEPTH / 8) &&
301 required_mem_len <= info->fix.smem_len) {
302 var->xres_virtual = var->xres;
303 var->yres_virtual = var->yres;
309 static int xenfb_set_par(struct fb_info *info)
311 struct xenfb_info *xenfb_info;
314 xenfb_info = info->par;
316 spin_lock_irqsave(&xenfb_info->resize_lock, flags);
317 xenfb_info->resize.type = XENFB_TYPE_RESIZE;
318 xenfb_info->resize.width = info->var.xres;
319 xenfb_info->resize.height = info->var.yres;
320 xenfb_info->resize.stride = info->fix.line_length;
321 xenfb_info->resize.depth = info->var.bits_per_pixel;
322 xenfb_info->resize.offset = 0;
323 xenfb_info->resize_dpy = 1;
324 spin_unlock_irqrestore(&xenfb_info->resize_lock, flags);
328 static struct fb_ops xenfb_fb_ops = {
329 .owner = THIS_MODULE,
330 .fb_read = fb_sys_read,
331 .fb_write = xenfb_write,
332 .fb_setcolreg = xenfb_setcolreg,
333 .fb_fillrect = xenfb_fillrect,
334 .fb_copyarea = xenfb_copyarea,
335 .fb_imageblit = xenfb_imageblit,
336 .fb_check_var = xenfb_check_var,
337 .fb_set_par = xenfb_set_par,
340 static irqreturn_t xenfb_event_handler(int rq, void *dev_id)
343 * No in events recognized, simply ignore them all.
344 * If you need to recognize some, see xen-kbdfront's
345 * input_handler() for how to do that.
347 struct xenfb_info *info = dev_id;
348 struct xenfb_page *page = info->page;
350 if (page->in_cons != page->in_prod) {
351 info->page->in_cons = info->page->in_prod;
352 notify_remote_via_irq(info->irq);
355 /* Flush dirty rectangle: */
356 xenfb_refresh(info, INT_MAX, INT_MAX, -INT_MAX, -INT_MAX);
361 static int __devinit xenfb_probe(struct xenbus_device *dev,
362 const struct xenbus_device_id *id)
364 struct xenfb_info *info;
365 struct fb_info *fb_info;
370 info = kzalloc(sizeof(*info), GFP_KERNEL);
372 xenbus_dev_fatal(dev, -ENOMEM, "allocating info structure");
376 /* Limit kernel param videoram amount to what is in xenstore */
377 if (xenbus_scanf(XBT_NIL, dev->otherend, "videoram", "%d", &val) == 1) {
378 if (val < video[KPARAM_MEM])
379 video[KPARAM_MEM] = val;
382 /* If requested res does not fit in available memory, use default */
383 fb_size = video[KPARAM_MEM] * 1024 * 1024;
384 if (video[KPARAM_WIDTH] * video[KPARAM_HEIGHT] * XENFB_DEPTH / 8
386 video[KPARAM_WIDTH] = XENFB_WIDTH;
387 video[KPARAM_HEIGHT] = XENFB_HEIGHT;
388 fb_size = XENFB_DEFAULT_FB_LEN;
391 dev_set_drvdata(&dev->dev, info);
394 info->x1 = info->y1 = INT_MAX;
395 spin_lock_init(&info->dirty_lock);
396 spin_lock_init(&info->resize_lock);
398 info->fb = vmalloc(fb_size);
399 if (info->fb == NULL)
401 memset(info->fb, 0, fb_size);
403 info->nr_pages = (fb_size + PAGE_SIZE - 1) >> PAGE_SHIFT;
405 info->mfns = vmalloc(sizeof(unsigned long) * info->nr_pages);
409 /* set up shared page */
410 info->page = (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
414 /* abusing framebuffer_alloc() to allocate pseudo_palette */
415 fb_info = framebuffer_alloc(sizeof(u32) * 256, NULL);
419 /* complete the abuse: */
420 fb_info->pseudo_palette = fb_info->par;
423 fb_info->screen_base = info->fb;
425 fb_info->fbops = &xenfb_fb_ops;
426 fb_info->var.xres_virtual = fb_info->var.xres = video[KPARAM_WIDTH];
427 fb_info->var.yres_virtual = fb_info->var.yres = video[KPARAM_HEIGHT];
428 fb_info->var.bits_per_pixel = XENFB_DEPTH;
430 fb_info->var.red = (struct fb_bitfield){16, 8, 0};
431 fb_info->var.green = (struct fb_bitfield){8, 8, 0};
432 fb_info->var.blue = (struct fb_bitfield){0, 8, 0};
434 fb_info->var.activate = FB_ACTIVATE_NOW;
435 fb_info->var.height = -1;
436 fb_info->var.width = -1;
437 fb_info->var.vmode = FB_VMODE_NONINTERLACED;
439 fb_info->fix.visual = FB_VISUAL_TRUECOLOR;
440 fb_info->fix.line_length = fb_info->var.xres * XENFB_DEPTH / 8;
441 fb_info->fix.smem_start = 0;
442 fb_info->fix.smem_len = fb_size;
443 strcpy(fb_info->fix.id, "xen");
444 fb_info->fix.type = FB_TYPE_PACKED_PIXELS;
445 fb_info->fix.accel = FB_ACCEL_NONE;
447 fb_info->flags = FBINFO_FLAG_DEFAULT | FBINFO_VIRTFB;
449 ret = fb_alloc_cmap(&fb_info->cmap, 256, 0);
451 framebuffer_release(fb_info);
452 xenbus_dev_fatal(dev, ret, "fb_alloc_cmap");
456 fb_info->fbdefio = &xenfb_defio;
457 fb_deferred_io_init(fb_info);
459 xenfb_init_shared_page(info, fb_info);
461 ret = xenfb_connect_backend(dev, info);
465 ret = register_framebuffer(fb_info);
467 fb_deferred_io_cleanup(fb_info);
468 fb_dealloc_cmap(&fb_info->cmap);
469 framebuffer_release(fb_info);
470 xenbus_dev_fatal(dev, ret, "register_framebuffer");
473 info->fb_info = fb_info;
475 xenfb_make_preferred_console();
480 xenbus_dev_fatal(dev, ret, "allocating device memory");
486 static __devinit void
487 xenfb_make_preferred_console(void)
491 if (console_set_on_cmdline)
494 acquire_console_sem();
495 for (c = console_drivers; c; c = c->next) {
496 if (!strcmp(c->name, "tty") && c->index == 0)
499 release_console_sem();
501 unregister_console(c);
502 c->flags |= CON_CONSDEV;
503 c->flags &= ~CON_PRINTBUFFER; /* don't print again */
508 static int xenfb_resume(struct xenbus_device *dev)
510 struct xenfb_info *info = dev_get_drvdata(&dev->dev);
512 xenfb_disconnect_backend(info);
513 xenfb_init_shared_page(info, info->fb_info);
514 return xenfb_connect_backend(dev, info);
517 static int xenfb_remove(struct xenbus_device *dev)
519 struct xenfb_info *info = dev_get_drvdata(&dev->dev);
521 xenfb_disconnect_backend(info);
523 fb_deferred_io_cleanup(info->fb_info);
524 unregister_framebuffer(info->fb_info);
525 fb_dealloc_cmap(&info->fb_info->cmap);
526 framebuffer_release(info->fb_info);
528 free_page((unsigned long)info->page);
536 static unsigned long vmalloc_to_mfn(void *address)
538 return pfn_to_mfn(vmalloc_to_pfn(address));
541 static void xenfb_init_shared_page(struct xenfb_info *info,
542 struct fb_info *fb_info)
545 int epd = PAGE_SIZE / sizeof(info->mfns[0]);
547 for (i = 0; i < info->nr_pages; i++)
548 info->mfns[i] = vmalloc_to_mfn(info->fb + i * PAGE_SIZE);
550 for (i = 0; i * epd < info->nr_pages; i++)
551 info->page->pd[i] = vmalloc_to_mfn(&info->mfns[i * epd]);
553 info->page->width = fb_info->var.xres;
554 info->page->height = fb_info->var.yres;
555 info->page->depth = fb_info->var.bits_per_pixel;
556 info->page->line_length = fb_info->fix.line_length;
557 info->page->mem_length = fb_info->fix.smem_len;
558 info->page->in_cons = info->page->in_prod = 0;
559 info->page->out_cons = info->page->out_prod = 0;
562 static int xenfb_connect_backend(struct xenbus_device *dev,
563 struct xenfb_info *info)
566 struct xenbus_transaction xbt;
568 ret = xenbus_alloc_evtchn(dev, &evtchn);
571 ret = bind_evtchn_to_irqhandler(evtchn, xenfb_event_handler,
572 0, dev->devicetype, info);
574 xenbus_free_evtchn(dev, evtchn);
575 xenbus_dev_fatal(dev, ret, "bind_evtchn_to_irqhandler");
581 ret = xenbus_transaction_start(&xbt);
583 xenbus_dev_fatal(dev, ret, "starting transaction");
586 ret = xenbus_printf(xbt, dev->nodename, "page-ref", "%lu",
587 virt_to_mfn(info->page));
590 ret = xenbus_printf(xbt, dev->nodename, "event-channel", "%u",
594 ret = xenbus_printf(xbt, dev->nodename, "protocol", "%s",
595 XEN_IO_PROTO_ABI_NATIVE);
598 ret = xenbus_printf(xbt, dev->nodename, "feature-update", "1");
601 ret = xenbus_transaction_end(xbt, 0);
605 xenbus_dev_fatal(dev, ret, "completing transaction");
609 xenbus_switch_state(dev, XenbusStateInitialised);
613 xenbus_transaction_end(xbt, 1);
614 xenbus_dev_fatal(dev, ret, "writing xenstore");
618 static void xenfb_disconnect_backend(struct xenfb_info *info)
620 /* Prevent xenfb refresh */
621 info->update_wanted = 0;
623 unbind_from_irqhandler(info->irq, info);
627 static void xenfb_backend_changed(struct xenbus_device *dev,
628 enum xenbus_state backend_state)
630 struct xenfb_info *info = dev_get_drvdata(&dev->dev);
633 switch (backend_state) {
634 case XenbusStateInitialising:
635 case XenbusStateInitialised:
636 case XenbusStateReconfiguring:
637 case XenbusStateReconfigured:
638 case XenbusStateUnknown:
639 case XenbusStateClosed:
642 case XenbusStateInitWait:
644 xenbus_switch_state(dev, XenbusStateConnected);
647 case XenbusStateConnected:
649 * Work around xenbus race condition: If backend goes
650 * through InitWait to Connected fast enough, we can
651 * get Connected twice here.
653 if (dev->state != XenbusStateConnected)
654 goto InitWait; /* no InitWait seen yet, fudge it */
656 if (xenbus_scanf(XBT_NIL, info->xbdev->otherend,
657 "request-update", "%d", &val) < 0)
660 info->update_wanted = 1;
662 if (xenbus_scanf(XBT_NIL, dev->otherend,
663 "feature-resize", "%d", &val) < 0)
665 info->feature_resize = val;
668 case XenbusStateClosing:
669 xenbus_frontend_closed(dev);
674 static struct xenbus_device_id xenfb_ids[] = {
679 static struct xenbus_driver xenfb_driver = {
681 .owner = THIS_MODULE,
683 .probe = xenfb_probe,
684 .remove = xenfb_remove,
685 .resume = xenfb_resume,
686 .otherend_changed = xenfb_backend_changed,
689 static int __init xenfb_init(void)
691 if (!xen_pv_domain())
694 /* Nothing to do if running in dom0. */
695 if (xen_initial_domain())
698 return xenbus_register_frontend(&xenfb_driver);
701 static void __exit xenfb_cleanup(void)
703 xenbus_unregister_driver(&xenfb_driver);
706 module_init(xenfb_init);
707 module_exit(xenfb_cleanup);
709 MODULE_DESCRIPTION("Xen virtual framebuffer device frontend");
710 MODULE_LICENSE("GPL");
711 MODULE_ALIAS("xen:vfb");