From e4dcff1f6e7582f76c2c9990b1d9111bbc8e26ef Mon Sep 17 00:00:00 2001 From: Markus Armbruster Date: Mon, 26 May 2008 23:31:11 +0100 Subject: [PATCH] xen pvfb: Dynamic mode support (screen resizing) The pvfb backend indicates dynamic mode support by creating node feature_resize with a non-zero value in its xenstore directory. xen-fbfront sends a resize notification event on mode change. Fully backwards compatible both ways. Framebuffer size and initial resolution can be controlled through kernel parameter xen_fbfront.video. The backend enforces a separate size limit, which it advertises in node videoram in its xenstore directory. xen-kbdfront gets the maximum screen resolution from nodes width and height in the backend's xenstore directory instead of hardcoding it. Additional goodie: support for larger framebuffers (512M on a 64-bit system with 4K pages). Changing the number of bits per pixels dynamically is not supported, yet. Ported from http://xenbits.xensource.com/linux-2.6.18-xen.hg?rev/92f7b3144f41 http://xenbits.xensource.com/linux-2.6.18-xen.hg?rev/bfc040135633 Signed-off-by: Pat Campbell Signed-off-by: Markus Armbruster Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Thomas Gleixner --- drivers/input/xen-kbdfront.c | 10 +++ drivers/video/xen-fbfront.c | 183 +++++++++++++++++++++++++++++++++------- include/xen/interface/io/fbif.h | 29 +++++-- 3 files changed, 188 insertions(+), 34 deletions(-) diff --git a/drivers/input/xen-kbdfront.c b/drivers/input/xen-kbdfront.c index eaf69cf..9ce3b3b 100644 --- a/drivers/input/xen-kbdfront.c +++ b/drivers/input/xen-kbdfront.c @@ -300,6 +300,16 @@ InitWait: */ if (dev->state != XenbusStateConnected) goto InitWait; /* no InitWait seen yet, fudge it */ + + /* Set input abs params to match backend screen res */ + if (xenbus_scanf(XBT_NIL, info->xbdev->otherend, + "width", "%d", &val) > 0) + input_set_abs_params(info->ptr, ABS_X, 0, val, 0, 0); + + if (xenbus_scanf(XBT_NIL, info->xbdev->otherend, + "height", "%d", &val) > 0) + input_set_abs_params(info->ptr, ABS_Y, 0, val, 0, 0); + break; case XenbusStateClosing: diff --git a/drivers/video/xen-fbfront.c b/drivers/video/xen-fbfront.c index 291eef6..47ed39b 100644 --- a/drivers/video/xen-fbfront.c +++ b/drivers/video/xen-fbfront.c @@ -43,23 +43,47 @@ struct xenfb_info { struct xenfb_page *page; unsigned long *mfns; int update_wanted; /* XENFB_TYPE_UPDATE wanted */ + int feature_resize; /* XENFB_TYPE_RESIZE ok */ + struct xenfb_resize resize; /* protected by resize_lock */ + int resize_dpy; /* ditto */ + spinlock_t resize_lock; struct xenbus_device *xbdev; }; -static u32 xenfb_mem_len = XENFB_WIDTH * XENFB_HEIGHT * XENFB_DEPTH / 8; +#define XENFB_DEFAULT_FB_LEN (XENFB_WIDTH * XENFB_HEIGHT * XENFB_DEPTH / 8) + +enum { KPARAM_MEM, KPARAM_WIDTH, KPARAM_HEIGHT, KPARAM_CNT }; +static int video[KPARAM_CNT] = { 2, XENFB_WIDTH, XENFB_HEIGHT }; +module_param_array(video, int, NULL, 0); +MODULE_PARM_DESC(video, + "Video memory size in MB, width, height in pixels (default 2,800,600)"); static void xenfb_make_preferred_console(void); static int xenfb_remove(struct xenbus_device *); -static void xenfb_init_shared_page(struct xenfb_info *); +static void xenfb_init_shared_page(struct xenfb_info *, struct fb_info *); static int xenfb_connect_backend(struct xenbus_device *, struct xenfb_info *); static void xenfb_disconnect_backend(struct xenfb_info *); +static void xenfb_send_event(struct xenfb_info *info, + union xenfb_out_event *event) +{ + u32 prod; + + prod = info->page->out_prod; + /* caller ensures !xenfb_queue_full() */ + mb(); /* ensure ring space available */ + XENFB_OUT_RING_REF(info->page, prod) = *event; + wmb(); /* ensure ring contents visible */ + info->page->out_prod = prod + 1; + + notify_remote_via_irq(info->irq); +} + static void xenfb_do_update(struct xenfb_info *info, int x, int y, int w, int h) { union xenfb_out_event event; - u32 prod; memset(&event, 0, sizeof(event)); event.type = XENFB_TYPE_UPDATE; @@ -68,14 +92,19 @@ static void xenfb_do_update(struct xenfb_info *info, event.update.width = w; event.update.height = h; - prod = info->page->out_prod; /* caller ensures !xenfb_queue_full() */ - mb(); /* ensure ring space available */ - XENFB_OUT_RING_REF(info->page, prod) = event; - wmb(); /* ensure ring contents visible */ - info->page->out_prod = prod + 1; + xenfb_send_event(info, &event); +} - notify_remote_via_irq(info->irq); +static void xenfb_do_resize(struct xenfb_info *info) +{ + union xenfb_out_event event; + + memset(&event, 0, sizeof(event)); + event.resize = info->resize; + + /* caller ensures !xenfb_queue_full() */ + xenfb_send_event(info, &event); } static int xenfb_queue_full(struct xenfb_info *info) @@ -87,12 +116,28 @@ static int xenfb_queue_full(struct xenfb_info *info) return prod - cons == XENFB_OUT_RING_LEN; } +static void xenfb_handle_resize_dpy(struct xenfb_info *info) +{ + unsigned long flags; + + spin_lock_irqsave(&info->resize_lock, flags); + if (info->resize_dpy) { + if (!xenfb_queue_full(info)) { + info->resize_dpy = 0; + xenfb_do_resize(info); + } + } + spin_unlock_irqrestore(&info->resize_lock, flags); +} + static void xenfb_refresh(struct xenfb_info *info, int x1, int y1, int w, int h) { unsigned long flags; - int y2 = y1 + h - 1; int x2 = x1 + w - 1; + int y2 = y1 + h - 1; + + xenfb_handle_resize_dpy(info); if (!info->update_wanted) return; @@ -225,6 +270,57 @@ static ssize_t xenfb_write(struct fb_info *p, const char __user *buf, return res; } +static int +xenfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info) +{ + struct xenfb_info *xenfb_info; + int required_mem_len; + + xenfb_info = info->par; + + if (!xenfb_info->feature_resize) { + if (var->xres == video[KPARAM_WIDTH] && + var->yres == video[KPARAM_HEIGHT] && + var->bits_per_pixel == xenfb_info->page->depth) { + return 0; + } + return -EINVAL; + } + + /* Can't resize past initial width and height */ + if (var->xres > video[KPARAM_WIDTH] || var->yres > video[KPARAM_HEIGHT]) + return -EINVAL; + + required_mem_len = var->xres * var->yres * xenfb_info->page->depth / 8; + if (var->bits_per_pixel == xenfb_info->page->depth && + var->xres <= info->fix.line_length / (XENFB_DEPTH / 8) && + required_mem_len <= info->fix.smem_len) { + var->xres_virtual = var->xres; + var->yres_virtual = var->yres; + return 0; + } + return -EINVAL; +} + +static int xenfb_set_par(struct fb_info *info) +{ + struct xenfb_info *xenfb_info; + unsigned long flags; + + xenfb_info = info->par; + + spin_lock_irqsave(&xenfb_info->resize_lock, flags); + xenfb_info->resize.type = XENFB_TYPE_RESIZE; + xenfb_info->resize.width = info->var.xres; + xenfb_info->resize.height = info->var.yres; + xenfb_info->resize.stride = info->fix.line_length; + xenfb_info->resize.depth = info->var.bits_per_pixel; + xenfb_info->resize.offset = 0; + xenfb_info->resize_dpy = 1; + spin_unlock_irqrestore(&xenfb_info->resize_lock, flags); + return 0; +} + static struct fb_ops xenfb_fb_ops = { .owner = THIS_MODULE, .fb_read = fb_sys_read, @@ -233,6 +329,8 @@ static struct fb_ops xenfb_fb_ops = { .fb_fillrect = xenfb_fillrect, .fb_copyarea = xenfb_copyarea, .fb_imageblit = xenfb_imageblit, + .fb_check_var = xenfb_check_var, + .fb_set_par = xenfb_set_par, }; static irqreturn_t xenfb_event_handler(int rq, void *dev_id) @@ -261,6 +359,8 @@ static int __devinit xenfb_probe(struct xenbus_device *dev, { struct xenfb_info *info; struct fb_info *fb_info; + int fb_size; + int val; int ret; info = kzalloc(sizeof(*info), GFP_KERNEL); @@ -268,18 +368,35 @@ static int __devinit xenfb_probe(struct xenbus_device *dev, xenbus_dev_fatal(dev, -ENOMEM, "allocating info structure"); return -ENOMEM; } + + /* Limit kernel param videoram amount to what is in xenstore */ + if (xenbus_scanf(XBT_NIL, dev->otherend, "videoram", "%d", &val) == 1) { + if (val < video[KPARAM_MEM]) + video[KPARAM_MEM] = val; + } + + /* If requested res does not fit in available memory, use default */ + fb_size = video[KPARAM_MEM] * 1024 * 1024; + if (video[KPARAM_WIDTH] * video[KPARAM_HEIGHT] * XENFB_DEPTH / 8 + > fb_size) { + video[KPARAM_WIDTH] = XENFB_WIDTH; + video[KPARAM_HEIGHT] = XENFB_HEIGHT; + fb_size = XENFB_DEFAULT_FB_LEN; + } + dev->dev.driver_data = info; info->xbdev = dev; info->irq = -1; info->x1 = info->y1 = INT_MAX; spin_lock_init(&info->dirty_lock); + spin_lock_init(&info->resize_lock); - info->fb = vmalloc(xenfb_mem_len); + info->fb = vmalloc(fb_size); if (info->fb == NULL) goto error_nomem; - memset(info->fb, 0, xenfb_mem_len); + memset(info->fb, 0, fb_size); - info->nr_pages = (xenfb_mem_len + PAGE_SIZE - 1) >> PAGE_SHIFT; + info->nr_pages = (fb_size + PAGE_SIZE - 1) >> PAGE_SHIFT; info->mfns = vmalloc(sizeof(unsigned long) * info->nr_pages); if (!info->mfns) @@ -290,8 +407,6 @@ static int __devinit xenfb_probe(struct xenbus_device *dev, if (!info->page) goto error_nomem; - xenfb_init_shared_page(info); - /* abusing framebuffer_alloc() to allocate pseudo_palette */ fb_info = framebuffer_alloc(sizeof(u32) * 256, NULL); if (fb_info == NULL) @@ -304,9 +419,9 @@ static int __devinit xenfb_probe(struct xenbus_device *dev, fb_info->screen_base = info->fb; fb_info->fbops = &xenfb_fb_ops; - fb_info->var.xres_virtual = fb_info->var.xres = info->page->width; - fb_info->var.yres_virtual = fb_info->var.yres = info->page->height; - fb_info->var.bits_per_pixel = info->page->depth; + fb_info->var.xres_virtual = fb_info->var.xres = video[KPARAM_WIDTH]; + fb_info->var.yres_virtual = fb_info->var.yres = video[KPARAM_HEIGHT]; + fb_info->var.bits_per_pixel = XENFB_DEPTH; fb_info->var.red = (struct fb_bitfield){16, 8, 0}; fb_info->var.green = (struct fb_bitfield){8, 8, 0}; @@ -318,9 +433,9 @@ static int __devinit xenfb_probe(struct xenbus_device *dev, fb_info->var.vmode = FB_VMODE_NONINTERLACED; fb_info->fix.visual = FB_VISUAL_TRUECOLOR; - fb_info->fix.line_length = info->page->line_length; + fb_info->fix.line_length = fb_info->var.xres * XENFB_DEPTH / 8; fb_info->fix.smem_start = 0; - fb_info->fix.smem_len = xenfb_mem_len; + fb_info->fix.smem_len = fb_size; strcpy(fb_info->fix.id, "xen"); fb_info->fix.type = FB_TYPE_PACKED_PIXELS; fb_info->fix.accel = FB_ACCEL_NONE; @@ -337,6 +452,8 @@ static int __devinit xenfb_probe(struct xenbus_device *dev, fb_info->fbdefio = &xenfb_defio; fb_deferred_io_init(fb_info); + xenfb_init_shared_page(info, fb_info); + ret = register_framebuffer(fb_info); if (ret) { fb_deferred_io_cleanup(fb_info); @@ -389,7 +506,7 @@ static int xenfb_resume(struct xenbus_device *dev) struct xenfb_info *info = dev->dev.driver_data; xenfb_disconnect_backend(info); - xenfb_init_shared_page(info); + xenfb_init_shared_page(info, info->fb_info); return xenfb_connect_backend(dev, info); } @@ -417,20 +534,23 @@ static unsigned long vmalloc_to_mfn(void *address) return pfn_to_mfn(vmalloc_to_pfn(address)); } -static void xenfb_init_shared_page(struct xenfb_info *info) +static void xenfb_init_shared_page(struct xenfb_info *info, + struct fb_info *fb_info) { int i; + int epd = PAGE_SIZE / sizeof(info->mfns[0]); for (i = 0; i < info->nr_pages; i++) info->mfns[i] = vmalloc_to_mfn(info->fb + i * PAGE_SIZE); - info->page->pd[0] = vmalloc_to_mfn(info->mfns); - info->page->pd[1] = 0; - info->page->width = XENFB_WIDTH; - info->page->height = XENFB_HEIGHT; - info->page->depth = XENFB_DEPTH; - info->page->line_length = (info->page->depth / 8) * info->page->width; - info->page->mem_length = xenfb_mem_len; + for (i = 0; i * epd < info->nr_pages; i++) + info->page->pd[i] = vmalloc_to_mfn(&info->mfns[i * epd]); + + info->page->width = fb_info->var.xres; + info->page->height = fb_info->var.yres; + info->page->depth = fb_info->var.bits_per_pixel; + info->page->line_length = fb_info->fix.line_length; + info->page->mem_length = fb_info->fix.smem_len; info->page->in_cons = info->page->in_prod = 0; info->page->out_cons = info->page->out_prod = 0; } @@ -530,6 +650,11 @@ InitWait: val = 0; if (val) info->update_wanted = 1; + + if (xenbus_scanf(XBT_NIL, dev->otherend, + "feature-resize", "%d", &val) < 0) + val = 0; + info->feature_resize = val; break; case XenbusStateClosing: diff --git a/include/xen/interface/io/fbif.h b/include/xen/interface/io/fbif.h index 5a934dd..974a51e 100644 --- a/include/xen/interface/io/fbif.h +++ b/include/xen/interface/io/fbif.h @@ -49,11 +49,27 @@ struct xenfb_update { int32_t height; /* rect height */ }; +/* + * Framebuffer resize notification event + * Capable backend sets feature-resize in xenstore. + */ +#define XENFB_TYPE_RESIZE 3 + +struct xenfb_resize { + uint8_t type; /* XENFB_TYPE_RESIZE */ + int32_t width; /* width in pixels */ + int32_t height; /* height in pixels */ + int32_t stride; /* stride in bytes */ + int32_t depth; /* depth in bits */ + int32_t offset; /* start offset within framebuffer */ +}; + #define XENFB_OUT_EVENT_SIZE 40 union xenfb_out_event { uint8_t type; struct xenfb_update update; + struct xenfb_resize resize; char pad[XENFB_OUT_EVENT_SIZE]; }; @@ -105,15 +121,18 @@ struct xenfb_page { * Each directory page holds PAGE_SIZE / sizeof(*pd) * framebuffer pages, and can thus map up to PAGE_SIZE * * PAGE_SIZE / sizeof(*pd) bytes. With PAGE_SIZE == 4096 and - * sizeof(unsigned long) == 4, that's 4 Megs. Two directory - * pages should be enough for a while. + * sizeof(unsigned long) == 4/8, that's 4 Megs 32 bit and 2 + * Megs 64 bit. 256 directories give enough room for a 512 + * Meg framebuffer with a max resolution of 12,800x10,240. + * Should be enough for a while with room leftover for + * expansion. */ - unsigned long pd[2]; + unsigned long pd[256]; }; /* - * Wart: xenkbd needs to know resolution. Put it here until a better - * solution is found, but don't leak it to the backend. + * Wart: xenkbd needs to know default resolution. Put it here until a + * better solution is found, but don't leak it to the backend. */ #ifdef __KERNEL__ #define XENFB_WIDTH 800 -- 1.8.2.3