This patch adds serveral new ioctls and a new query to get_param query to
support PCI MGA cards.
Two ioctls were added to implement interrupt based waiting. With this
change, the client-side driver no longer needs to map the primary DMA
region or the MMIO region. Previously, end-of-frame waiting was done by
busy waiting in the client-side driver until one of the MMIO registers
(the current DMA pointer) matched a pointer to the end of primary DMA
space. By using interrupts, the busy waiting and the extra mappings are
removed.
A third ioctl was added to bootstrap DMA. This ioctl, which is used by the
X-server, moves a *LOT* of code from the X-server into the kernel. This
allows the kernel to do whatever needs to be done to setup DMA buffers.
The entire process and the locations of the buffers are hidden from
user-mode.
Additionally, a get_param query was added to differentiate between G4x0
cards and G550 cards. A gap was left in the numbering sequence so that,
if needed, G450 cards could be distinguished from G400 cards. According
to Ville Syrjälä, the G4x0 cards and the G550 cards handle
anisotropic filtering differently. This seems the most compatible way
to let the client-side driver know which card it's own. Doing this very
small change now eliminates the need to bump the DRM minor version
twice.
http://marc.theaimsgroup.com/?l=dri-devel&m=106625815319773&w=2
A number of ioctl handlers in linux-core were also modified so that they
could be called in-kernel. In these cases, the in-kernel callable
version kept the existing name (e.g., drm_agp_acquire) and the ioctl
handler added _ioctl to the name (e.g., drm_agp_acquire_ioctl).
This patch also replaces the drm_agp_do_release function with
drm_agp_release. drm_agp_release (drm_core_agp_release in the previous
patch) is very similar to drm_agp_do_release, and I saw no reason to
have both.
This commit *breaks the build* on BSD. Eric said that he would make the
required updates to the BSD side soon.
Xorg bug: 3259 Reviewed by: Eric Anholt
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* For the very latest on DRI development, please see: *
* http://dri.sourceforge.net/ *
************************************************************
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://precisioninsight.com/piinsights.html
For specific information about kernel-level support, see:
The Direct Rendering Manager, Kernel Support for the Direct Rendering
Infrastructure
http://precisioninsight.com/dr/drm.html
Hardware Locking for the Direct Rendering Infrastructure
http://precisioninsight.com/dr/locking.html
A Security Analysis of the Direct Rendering Infrastructure
http://precisioninsight.com/dr/security.html
************************************************************
* For the very latest on DRI development, please see: *
* http://dri.sourceforge.net/ *
************************************************************