user/sven/linux.git/include/video, branch v4.19.115

udlfb: introduce a rendering mutex

2019-05-25T16:23:30Z

commit babc250e278eac7b0e671bdaedf833759b43bb78 upstream. Rendering calls may be done simultaneously from the workqueue, dlfb_ops_write, dlfb_ops_ioctl, dlfb_ops_set_par and dlfb_dpy_deferred_io. The code is robust enough so that it won't crash on concurrent rendering. However, concurrent rendering may cause display corruption if the same pixel is simultaneously being rendered. In order to avoid this corruption, this patch adds a mutex around the rendering calls. Signed-off-by: Mikulas Patocka Cc: Bernie Thompson Cc: Ladislav Michl Cc: [b.zolnierkie: replace "dlfb:" with "uldfb:" in the patch summary] Signed-off-by: Bartlomiej Zolnierkiewicz Signed-off-by: Greg Kroah-Hartman

udlfb: fix sleeping inside spinlock

2019-05-25T16:23:29Z

commit 6b11f9d8433b471fdd3ebed232b43a4b723be6ff upstream. If a framebuffer device is used as a console, the rendering calls (copyarea, fillrect, imageblit) may be done with the console spinlock held. On udlfb, these function call dlfb_handle_damage that takes a blocking semaphore before acquiring an URB. In order to fix the bug, this patch changes the calls copyarea, fillrect and imageblit to offload USB work to a workqueue. A side effect of this patch is 3x improvement in console scrolling speed because the device doesn't have to be updated after each copyarea call. Signed-off-by: Mikulas Patocka Cc: Bernie Thompson Cc: Ladislav Michl Cc: Signed-off-by: Bartlomiej Zolnierkiewicz Signed-off-by: Greg Kroah-Hartman

udlfb: handle unplug properly

2019-02-27T09:09:03Z

commit 68a958a915ca912b8ce71b9eea7445996f6e681e upstream. The udlfb driver maintained an open count and cleaned up itself when the count reached zero. But the console is also counted in the reference count - so, if the user unplugged the device, the open count would not drop to zero and the driver stayed loaded with console attached. If the user re-plugged the adapter, it would create a device /dev/fb1, show green screen and the access to the console would be lost. The framebuffer subsystem has reference counting on its own - in order to fix the unplug bug, we rely the framebuffer reference counting. When the user unplugs the adapter, we call unregister_framebuffer unconditionally. unregister_framebuffer will unbind the console, wait until all users stop using the framebuffer and then call the fb_destroy method. The fb_destroy cleans up the USB driver. This patch makes the following changes: * Drop dlfb->kref and rely on implicit framebuffer reference counting instead. * dlfb_usb_disconnect calls unregister_framebuffer, the rest of driver cleanup is done in the function dlfb_ops_destroy. dlfb_ops_destroy will be called by the framebuffer subsystem when no processes have the framebuffer open or mapped. * We don't use workqueue during initialization, but initialize directly from dlfb_usb_probe. The workqueue could race with dlfb_usb_disconnect and this racing would produce various kinds of memory corruption. * We use usb_get_dev and usb_put_dev to make sure that the USB subsystem doesn't free the device under us. Signed-off-by: Mikulas Patocka cc: Dave Airlie Cc: Bernie Thompson , Cc: Ladislav Michl Signed-off-by: Bartlomiej Zolnierkiewicz Signed-off-by: Greg Kroah-Hartman

Merge tag 'fbdev-v4.19' of https://github.com/bzolnier/linux

2018-08-23T22:44:58Z

Pull fbdev updates from Bartlomiej Zolnierkiewicz: "Mostly small fixes and cleanups for fb drivers (the biggest updates are for udlfb and pxafb drivers). This also adds deferred console takeover support to the console code and efifb driver. Summary: - add support for deferred console takeover, when enabled defers fbcon taking over the console from the dummy console until the first text is displayed on the console - together with the "quiet" kernel commandline option this allows fbcon to still be used together with a smooth graphical bootup (Hans de Goede) - improve console locking debugging code (Thomas Zimmermann) - copy the ACPI BGRT boot graphics to the framebuffer when deferred console takeover support is used in efifb driver (Hans de Goede) - update udlfb driver - fix lost console when the user unplugs a USB adapter, fix the screen corruption issue, fix locking and add some performance optimizations (Mikulas Patocka) - update pxafb driver - fix using uninitialized memory, switch to devm_* API, handle initialization errors and add support for lcd-supply regulator (Daniel Mack) - add support for boards booted with a DeviceTree in pxa3xx_gcu driver (Daniel Mack) - rename omap2 module to omap2fb.ko to avoid conflicts with omap1 driver (Arnd Bergmann) - enable ACPI-based enumeration for goldfishfb driver (Yu Ning) - fix goldfishfb driver to make user space Android code use 60 fps (Christoffer Dall) - print big fat warning when nomodeset kernel parameter is used in vgacon driver (Lyude Paul) - remove VLA usage from fsl-diu-fb driver (Kees Cook) - misc fixes (Julia Lawall, Geert Uytterhoeven, Fredrik Noring, Yisheng Xie, Dan Carpenter, Daniel Vetter, Anton Vasilyev, Randy Dunlap, Gustavo A. R. Silva, Colin Ian King, Fengguang Wu) - misc cleanups (Roman Kiryanov, Yisheng Xie, Colin Ian King)" * tag 'fbdev-v4.19' of https://github.com/bzolnier/linux: (54 commits) Documentation/fb: corrections for fbcon.txt fbcon: Do not takeover the console from atomic context dummycon: Stop exporting dummycon_[un]register_output_notifier fbcon: Only defer console takeover if the current console driver is the dummycon fbcon: Only allow FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER if fbdev is builtin fbdev: omap2: omapfb: fix ifnullfree.cocci warnings fbdev: omap2: omapfb: fix bugon.cocci warnings fbdev: omap2: omapfb: fix boolreturn.cocci warnings fb: amifb: fix build warnings when not builtin fbdev/core: Disable console-lock warnings when fb.lockless_register_fb is set console: Replace #if 0 with atomic var 'ignore_console_lock_warning' udlfb: use spin_lock_irq instead of spin_lock_irqsave udlfb: avoid prefetch udlfb: optimization - test the backing buffer udlfb: allow reallocating the framebuffer udlfb: set line_length in dlfb_ops_set_par udlfb: handle allocation failure udlfb: set optimal write delay udlfb: make a local copy of fb_ops udlfb: don't switch if we are switching to the same videomode ...

udlfb: allow reallocating the framebuffer

2018-07-25T13:41:56Z

This patch changes udlfb so that it may reallocate the framebuffer when setting higher-resolution mode. If we boot the system without monitor attached, udlfb creates a framebuffer with the size 800x600. This patch makes it possible to select higher videomode with the fbset command when a monitor is attached. Note that there is no reliable way to prevent the system from touching the old framebuffer, so we must not free it. We add it to the list dlfb->deferred_free and free it when the driver is unloaded. Signed-off-by: Mikulas Patocka [b.zolnierkie: sparse fixes] Signed-off-by: Bartlomiej Zolnierkiewicz

udlfb: set optimal write delay

2018-07-25T13:41:55Z

The default delay 5 jiffies is too much when the kernel is compiled with HZ=100 - it results in jumpy cursor in Xwindow. In order to find out the optimal delay, I benchmarked the driver on 1280x720x30fps video. I found out that with HZ=1000, 10ms is acceptable, but with HZ=250 or HZ=300, we need 4ms, so that the video is played without any frame skips. This patch changes the delay to this value. Signed-off-by: Mikulas Patocka Cc: stable@vger.kernel.org Signed-off-by: Bartlomiej Zolnierkiewicz

udlfb: make a local copy of fb_ops

2018-07-25T13:41:55Z

The defio subsystem overwrites the method fb_osp->mmap. That method is stored in module's static data - and that means that if we have multiple diplaylink adapters, they will over write each other's method. In order to avoid interference between multiple adapters, we copy the fb_ops structure to a device-local memory. Signed-off-by: Mikulas Patocka Cc: stable@vger.kernel.org Signed-off-by: Bartlomiej Zolnierkiewicz

udlfb: don't switch if we are switching to the same videomode

2018-07-25T13:41:55Z

The udlfb driver reprograms the hardware everytime the user switches the console, that makes quite unusable when working on the console. This patch makes the driver remember the videomode we are in and avoid reprogramming the hardware if we switch to the same videomode. We mask the "activate" field and the "FB_VMODE_SMOOTH_XPAN" flag when comparing the videomode, because they cause spurious switches when switching to and from the Xserver. Signed-off-by: Mikulas Patocka Cc: stable@vger.kernel.org Signed-off-by: Bartlomiej Zolnierkiewicz

udlfb: fix semaphore value leak

2018-07-25T13:41:54Z

I observed that the performance of the udl fb driver degrades over time. On a freshly booted machine, it takes 6 seconds to do "ls -la /usr/bin"; after some time of use, the same operation takes 14 seconds. The reason is that the value of "limit_sem" decays over time. The udl driver uses a semaphore "limit_set" to specify how many free urbs are there on dlfb->urbs.list. If the count is zero, the "down" operation will sleep until some urbs are added to the freelist. In order to avoid some hypothetical deadlock, the driver will not call "up" immediately, but it will offload it to a workqueue. The problem is that if we call "schedule_delayed_work" on the same work item multiple times, the work item may only be executed once. This is happening: * some urb completes * dlfb_urb_completion adds it to the free list * dlfb_urb_completion calls schedule_delayed_work to schedule the function dlfb_release_urb_work to increase the semaphore count * as the urb is on the free list, some other task grabs it and submits it * the submitted urb completes, dlfb_urb_completion is called again * dlfb_urb_completion calls schedule_delayed_work, but the work is already scheduled, so it does nothing * finally, dlfb_release_urb_work is called, it increases the semaphore count by 1, although it should increase it by 2 So, the semaphore count is decreasing over time, and this causes gradual performance degradation. Note that in the current kernel, the "up" function may be called from interrupt and it may race with the "down" function called by another thread, so we don't have to offload the call of "up" to a workqueue at all. This patch removes the workqueue code. The patch also changes "down_interruptible" to "down" in dlfb_free_urb_list, so that we will clean up the driver properly even if a signal arrives. With this patch, the performance of udlfb no longer degrades. Signed-off-by: Mikulas Patocka Cc: stable@vger.kernel.org [b.zolnierkie: fix immediatelly -> immediately typo] Signed-off-by: Bartlomiej Zolnierkiewicz

drm: Add support for pps and compression mode command packet

2018-07-25T11:51:05Z

After enabling DSC we need to send compression mode command packet and pps data packet, for which 2 new data types are added 07h Compression Mode Data Type Write , short write, 2 parameters 0Ah PPS Long Write (word count determines number of bytes) This patch adds support to send these packets. Cc: David Airlie Cc: Jean-Christophe Plagniol-Villard Cc: Tomi Valkeinen Cc: dri-devel@lists.freedesktop.org Cc: linux-kernel@vger.kernel.org Cc: linux-fbdev@vger.kernel.org Changes in v3: - None Signed-off-by: vkorjani [seanpaul removed pps_write_buffer fn, added types to packet_format helpers] Signed-off-by: Sean Paul Signed-off-by: Rob Clark