linux/drivers/gpu/drm
Chris Wilson 7782de3bd6 drm/i915: Disable FBC across page-flipping
Page-flipping updates the scanout address, nukes the FBC compressed
image and so forces an FBC update so that the displayed image remains
consistent. However, page-flipping does not update the FBC registers
themselves, which remain pointing to both the old address and the old
CPU fence. Future updates to the new front-buffer (scanout) are then
undetected!

This first approach to demonstrate the issue and highlight the fix,
simply disables FBC upon page-flip (a recompression will be forced on
every flip so FBC becomes immaterial) and then re-enables FBC in the
page-flip finish work function, so that the FBC registers are now
pointing to the new framebuffer and front-buffer rendering works once
more.

Ideally, we want to only re-enable FBC after page-flipping is complete,
as otherwise we are just wasting cycles and power (with needless
recompression) whilst the page-flipping application is still running.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=33487
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Keith Packard <keithp@keithp.com>
2011-07-08 10:23:15 -07:00
..
i2c
i810 drm: rework PCI/platform driver interface. 2011-02-07 13:09:36 +10:00
i915 drm/i915: Disable FBC across page-flipping 2011-07-08 10:23:15 -07:00
mga alpha, drm: Remove obsolete Alpha support in MGA DRM code 2011-06-14 09:32:56 +10:00
nouveau Revert "drm/nvc0: recognise 0xdX chipsets as NV_C0" 2011-07-02 07:10:20 +10:00
r128 drm: rework PCI/platform driver interface. 2011-02-07 13:09:36 +10:00
radeon drm/radeon/kms: fix typo in cayman reg offset 2011-07-02 07:09:19 +10:00
savage savage: remove unnecessary if statement 2011-06-14 09:29:12 +10:00
sis drm: rework PCI/platform driver interface. 2011-02-07 13:09:36 +10:00
tdfx drm: rework PCI/platform driver interface. 2011-02-07 13:09:36 +10:00
ttm drm/ttm: use shmem_read_mapping_page 2011-06-27 18:00:13 -07:00
via drm: rework PCI/platform driver interface. 2011-02-07 13:09:36 +10:00
vmwgfx Fix common misspellings 2011-03-31 11:26:23 -03:00
ati_pcigart.c
drm_agpsupport.c drm: kill drm_agp_chipset_flush 2010-11-23 20:14:44 +00:00
drm_auth.c
drm_buffer.c
drm_bufs.c drm: Compare only lower 32 bits of framebuffer map offsets 2011-06-14 11:09:54 +10:00
drm_cache.c
drm_context.c
drm_crtc_helper.c drm: bpp and depth changes require full mode sets 2011-07-07 13:20:49 -07:00
drm_crtc.c drm: fix fbs in DRM_IOCTL_MODE_GETRESOURCES ioctl 2011-06-09 14:31:09 +10:00
drm_debugfs.c
drm_dma.c
drm_dp_i2c_helper.c
drm_drv.c drm/core: add ioctl to query device/driver capabilities 2011-03-04 14:47:30 +10:00
drm_edid_modes.h drm: Mark constant arrays of drm_display_mode const 2011-02-23 11:13:11 +10:00
drm_edid.c drm/radeon: workaround a hw bug on some radeon chipsets with all-0 EDIDs. 2011-06-16 16:30:54 +10:00
drm_encoder_slave.c
drm_fb_helper.c drm: Take lock around probes for drm_fb_helper_hotplug_event 2011-05-16 12:01:43 +10:00
drm_fops.c drm/switcheroo: track state of switch in drivers. 2011-01-05 13:45:30 +10:00
drm_gem.c drm/i915: use shmem_read_mapping_page 2011-06-27 18:00:13 -07:00
drm_global.c
drm_hashtab.c drm: Remove unused members from struct drm_open_hash 2011-02-23 11:16:40 +10:00
drm_info.c Merge remote branch 'intel/drm-intel-next' of ../drm-next into drm-core-next 2011-03-14 14:15:13 +10:00
drm_ioc32.c drivers/gpu/drm: use printk_ratelimited instead of printk_ratelimit 2011-06-16 16:32:15 +10:00
drm_ioctl.c drm/vblank: update recently added vbl interface to be more future proof. 2011-03-24 21:28:46 +10:00
drm_irq.c Merge remote branch 'keithp/drm-intel-next' of /ssd/git/drm-next into drm-core-next 2011-05-16 10:45:40 +10:00
drm_lock.c
drm_memory.c
drm_mm.c drm: mm: fix debug output 2011-05-09 09:14:45 +10:00
drm_modes.c drm/fb: fix CONFIG_DRM=m && CONFIG_FB=n 2011-05-04 13:08:58 +10:00
drm_pci.c drm: populate irq_by_busid-member for pci 2011-06-16 16:26:45 +10:00
drm_platform.c drm: rework PCI/platform driver interface. 2011-02-07 13:09:36 +10:00
drm_proc.c
drm_scatter.c
drm_sman.c GPU DRM: Remove unnecessary casts of void ptr returning alloc function return values 2011-01-19 15:24:49 +01:00
drm_stub.c drm: Create and use drm_err 2011-04-28 14:53:02 +10:00
drm_sysfs.c drm: Hold the mode mutex whilst probing for sysfs status 2011-03-16 11:23:04 +10:00
drm_trace_points.c
drm_trace.h
drm_usb.c drm: add usb framework 2011-02-07 13:09:42 +10:00
drm_vm.c alpha/drm: Cleanup Alpha support in DRM generic code 2011-06-14 09:31:37 +10:00
Kconfig drm: select FRAMEBUFFER_CONSOLE_PRIMARY if we have FRAMEBUFFER_CONSOLE 2011-04-27 16:54:06 +10:00
Makefile drm: add usb framework 2011-02-07 13:09:42 +10:00
README.drm

************************************************************
* For the very latest on DRI development, please see:      *
*     http://dri.freedesktop.org/                          *
************************************************************

The Direct Rendering Manager (drm) is a device-independent kernel-level
device driver that provides support for the XFree86 Direct Rendering
Infrastructure (DRI).

The DRM supports the Direct Rendering Infrastructure (DRI) in four major
ways:

    1. The DRM provides synchronized access to the graphics hardware via
       the use of an optimized two-tiered lock.

    2. The DRM enforces the DRI security policy for access to the graphics
       hardware by only allowing authenticated X11 clients access to
       restricted regions of memory.

    3. The DRM provides a generic DMA engine, complete with multiple
       queues and the ability to detect the need for an OpenGL context
       switch.

    4. The DRM is extensible via the use of small device-specific modules
       that rely extensively on the API exported by the DRM module.


Documentation on the DRI is available from:
    http://dri.freedesktop.org/wiki/Documentation
    http://sourceforge.net/project/showfiles.php?group_id=387
    http://dri.sourceforge.net/doc/

For specific information about kernel-level support, see:

    The Direct Rendering Manager, Kernel Support for the Direct Rendering
    Infrastructure
    http://dri.sourceforge.net/doc/drm_low_level.html

    Hardware Locking for the Direct Rendering Infrastructure
    http://dri.sourceforge.net/doc/hardware_locking_low_level.html

    A Security Analysis of the Direct Rendering Infrastructure
    http://dri.sourceforge.net/doc/security_low_level.html