linux/drivers/gpu/drm
Paulo Zanoni dce56b3c62 drm/i915: save some time when waiting the eDP timings
The eDP spec defines some points where after you do action A, you have
to wait some time before action B. The thing is that in our driver
action B does not happen exactly after action A, but we still use
msleep() calls directly. What this patch does is that we record the
timestamp of when action A happened, then, just before action B, we
look at how much time has passed and only sleep the remaining amount
needed.

With this change, I am able to save about 5-20ms (out of the total
200ms) of the backlight_off delay and completely skip the 1ms
backlight_on delay. The 600ms vdd_off delay doesn't happen during
normal usage anymore due to a previous patch.

v2: - Rename ironlake_wait_jiffies_delay to intel_wait_until_after and
      move it to intel_display.c
    - Fix the msleep call: diff is in jiffies
v3: - Use "tmp_jiffies" so we don't need to worry about the value of
      "jiffies" advancing while we're doing the math.
v4: - Rename function again.
    - Move function to i915_drv.h.
    - Store last_power_cycle at edp_panel_off too.
    - Use msecs_to_jiffies_timeout, then replace the msleep with an
      open-coded version that avoids the extra +1 jiffy.
    - Try to add units to every variable name so we don't confuse
      jiffies with milliseconds.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-01-24 17:22:46 +01:00
..
armada Merge branch 'drm-intel-next' of git://people.freedesktop.org/~danvet/drm-intel into drm-next 2014-01-20 10:21:54 +10:00
ast drivers: gpu: Mark functions as static in ast_ttm.c 2014-01-14 12:59:16 +10:00
bochs drm/bochs: new driver 2013-12-23 11:02:39 +10:00
cirrus drivers: gpu: Mark functions as static and remove unused function in cirrus_ttm.c 2014-01-14 12:59:19 +10:00
exynos drm/exynos: fix build error caused by removed drm core macros 2014-01-07 16:53:25 +09:00
gma500 drm/gma500: Remove unused function declaration 2014-01-14 12:38:40 +10:00
i2c drm/i2c: tda998x: set VIF for full range, underscanned display 2013-10-18 15:58:32 +01:00
i810 drm: kill DRIVER_REQUIRE_AGP 2013-12-18 11:17:53 +10:00
i915 drm/i915: save some time when waiting the eDP timings 2014-01-24 17:22:46 +01:00
mga drivers: gpu: Include appropriate header file in mga_ioc32.c 2014-01-14 12:59:24 +10:00
mgag200 drm/mgag200: fix oops in cursor code. 2014-01-16 14:43:04 +10:00
msm drm: store the gem vma offset manager in a typed pointer 2014-01-14 12:38:32 +10:00
nouveau Merge branch 'drm-intel-next' of git://people.freedesktop.org/~danvet/drm-intel into drm-next 2014-01-20 10:21:54 +10:00
omapdrm drm: store the gem vma offset manager in a typed pointer 2014-01-14 12:38:32 +10:00
panel drm/panel: Add support for Panasonic VVX10F004B0 2013-12-17 18:09:58 +01:00
qxl gpu: fix qxl missing crc32_le 2014-01-14 13:08:37 +10:00
r128 drivers: gpu: Include appropriate header file in r128_ioc32.c 2014-01-14 13:05:37 +10:00
radeon Merge branch 'drm-vbl-timestamp' of git://gitorious.org/vsyrjala/linux into drm-next 2014-01-22 09:13:13 +10:00
rcar-du Merge branch 'drm/next/du' of git://linuxtv.org/pinchartl/fbdev into drm-next 2013-12-23 10:42:36 +10:00
savage drm: Kill DRM_*MEMORYBARRIER 2013-12-18 11:35:21 +10:00
shmobile drm/shmob: call drm_put_dev directly from ->remove hook 2013-12-18 11:05:46 +10:00
sis drivers: gpu: Mark function as static in sis_drv.c 2014-01-14 13:04:33 +10:00
tdfx drm: rip out drm_core_has_MTRR checks 2013-08-19 14:11:44 +10:00
tegra drm/tegra: Changes for v3.14-rc1 2013-12-23 10:43:42 +10:00
tilcdc drm: store the gem vma offset manager in a typed pointer 2014-01-14 12:38:32 +10:00
ttm Merge branch 'drm-intel-next' of git://people.freedesktop.org/~danvet/drm-intel into drm-next 2014-01-20 10:21:54 +10:00
udl drm: Push dirtyfb ioctl kms locking down to drivers 2013-12-18 10:49:08 +10:00
via drivers: gpu: Mark function as static in via_drv.c 2014-01-14 13:05:00 +10:00
vmwgfx drm/vmwgfx: Fix recently introduced sparse / smatch warnings and errors 2014-01-21 13:22:18 +01:00
Kconfig drm/bochs: new driver 2013-12-23 11:02:39 +10:00
Makefile drm/bochs: new driver 2013-12-23 11:02:39 +10:00
README.drm
ati_pcigart.c
drm_agpsupport.c drm: rip out DRM_AGP_MEM and DRM_AGP_KERN 2013-12-18 11:32:55 +10:00
drm_auth.c
drm_buffer.c drm: Kill DRM_COPY_(TO|FROM)_USER 2013-12-18 11:35:01 +10:00
drm_bufs.c drm: rip out drm_core_has_AGP 2013-12-18 11:20:04 +10:00
drm_cache.c
drm_context.c drm: Kill ctx_count from struct drm_device 2013-10-09 15:55:32 +10:00
drm_crtc.c drm: Push dirtyfb ioctl kms locking down to drivers 2013-12-18 10:49:08 +10:00
drm_crtc_helper.c drm: Pass the display mode to drm_calc_timestamping_constants() 2014-01-20 11:04:46 +02:00
drm_debugfs.c drm: Make drm_debugfs_list const 2013-11-06 12:05:21 +10:00
drm_dma.c drm: mark dma setup/teardown as legacy systems 2013-08-19 10:04:21 +10:00
drm_dp_helper.c drm/dp: constify DP DPCD helpers 2013-10-01 15:28:57 +10:00
drm_drv.c drm: Kill file_priv->ioctl_count tracking 2013-12-18 11:42:13 +10:00
drm_edid.c drm/edid: Populate picture aspect ratio for CEA modes 2014-01-20 18:32:21 +01:00
drm_edid_load.c drm/edid: Make edid_load() return a void * 2013-12-18 10:42:13 +10:00
drm_encoder_slave.c drm: encoder_slave: Don't use i2c_client->driver 2013-10-03 22:28:28 +02:00
drm_fb_cma_helper.c drm: Make drm_fb_cma_describe() static 2013-08-21 12:47:41 +10:00
drm_fb_helper.c drm: do not steal the display if we have a master 2013-12-18 10:47:20 +10:00
drm_flip_work.c kfifo API type safety 2013-11-15 09:32:23 +09:00
drm_fops.c drm: remove dev->vma_count 2013-12-18 11:43:29 +10:00
drm_gem.c drm/gem: Always initialize the gem object in object_init 2014-01-21 10:19:58 +01:00
drm_gem_cma_helper.c Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2013-09-05 10:17:26 -07:00
drm_global.c drm: Remove unused variable in drm_global_item_ref() 2013-10-01 15:28:58 +10:00
drm_hashtab.c
drm_info.c drm: remove dev->vma_count 2013-12-18 11:43:29 +10:00
drm_ioc32.c
drm_ioctl.c drm: Add a STEREO_3D capability to the SET_CLIENT_CAP ioctl 2013-10-01 07:45:27 +02:00
drm_irq.c drm/radeon: Move the early vblank IRQ fixup to radeon_get_crtc_scanoutpos() 2014-01-20 12:21:35 +02:00
drm_lock.c drm: Kill drm perf counter leftovers 2013-10-09 15:55:33 +10:00
drm_memory.c drm: rip out DRM_AGP_MEM and DRM_AGP_KERN 2013-12-18 11:32:55 +10:00
drm_mipi_dsi.c drm: Add MIPI DSI bus support 2013-12-17 18:09:43 +01:00
drm_mm.c Merge tag 'drm-intel-next-2013-08-23' of git://people.freedesktop.org/~danvet/drm-intel into drm-next 2013-08-30 09:47:41 +10:00
drm_modes.c Revert "drm: copy mode type in drm_mode_connector_list_update()" 2014-01-14 12:50:49 +10:00
drm_panel.c drm: Add panel support 2013-12-17 18:09:46 +01:00
drm_pci.c drm: remove global_mutex locking around agp_init 2013-12-18 11:27:29 +10:00
drm_platform.c drm: restrict the device list for shadow attached drivers 2013-12-18 11:08:36 +10:00
drm_prime.c drm: Remove unused variable in drm_prime_sg_to_page_addr_arrays() 2013-10-01 15:28:58 +10:00
drm_rect.c
drm_scatter.c drm: disallow legacy sg ioctls for modesetting drivers 2013-08-19 10:04:06 +10:00
drm_stub.c Merge branch 'drm-intel-next' of git://people.freedesktop.org/~danvet/drm-intel into drm-next 2014-01-20 10:21:54 +10:00
drm_sysfs.c drm/sysfs: fix OOM verification 2013-11-28 14:35:23 +10:00
drm_trace.h
drm_trace_points.c
drm_usb.c drivers: gpu: Include appropriate header file in drm_usb.c 2014-01-14 12:53:41 +10:00
drm_vm.c drm: remove dev->vma_count 2013-12-18 11:43:29 +10:00
drm_vma_manager.c drm/vma: add access management helpers 2013-08-27 11:54:54 +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