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acrn-kernel/drivers/gpu/vga/Makefile

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PCI/GPU: implement VGA arbitration on Linux Background: Graphic devices are accessed through ranges in I/O or memory space. While most modern devices allow relocation of such ranges, some "Legacy" VGA devices implemented on PCI will typically have the same "hard-decoded" addresses as they did on ISA. For more details see "PCI Bus Binding to IEEE Std 1275-1994 Standard for Boot (Initialization Configuration) Firmware Revision 2.1" Section 7, Legacy Devices. The Resource Access Control (RAC) module inside the X server currently does the task of arbitration when more than one legacy device co-exists on the same machine. But the problem happens when these devices are trying to be accessed by different userspace clients (e.g. two server in parallel). Their address assignments conflict. Therefore an arbitration scheme _outside_ of the X server is needed to control the sharing of these resources. This document introduces the operation of the VGA arbiter implemented for Linux kernel. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Tiago Vignatti <tiago.vignatti@nokia.com> Signed-off-by: Dave Airlie <airlied@redhat.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-08-11 13:52:06 +08:00
obj-$(CONFIG_VGA_ARB) += vgaarb.o
vga_switcheroo: initial implementation (v15) Many new laptops now come with 2 gpus, one to be used for low power modes and one for gaming/on-ac applications. These GPUs are typically wired to the laptop panel and VGA ports via a multiplexer unit which is controlled via ACPI methods. 4 combinations of systems typically exist - with 2 ACPI methods. Intel/ATI - Lenovo W500/T500 - use ATPX ACPI method ATI/ATI - some ASUS - use ATPX ACPI Method Intel/Nvidia - - use _DSM ACPI method Nvidia/Nvidia - - use _DSM ACPI method. TODO: This patch adds support for the ATPX method and initial bits for the _DSM methods that need to written by someone with access to the hardware. Add a proper non-debugfs interface - need to get some proper testing first. v2: add power up/down support for both devices on W500 puts i915/radeon into D3 and cuts power to radeon. v3: redo probing methods, no DMI list, drm devices call to register with switcheroo, it tries to find an ATPX method on any device and once there is two devices + ATPX it inits the switcher. v4: ATPX msg handling using buffers - should work on more machines v5: rearchitect after more mjg59 discussion - move ATPX handling to radeon driver. v6: add file headers + initial nouveau bits (to be filled out). v7: merge delayed switcher code. v8: avoid suspend/resume of gpu that is off v9: rearchitect - mjg59 is always right. - move all ATPX code to radeon, should allow simpler DSM also proper ATRM handling v10: add ATRM support for radeon BIOS, add mutex to lock vgasr_priv v11: fix bug in resuming Intel for 2nd time. v12: start fixing up nvidia code blindly. v13: blindly guess at finishing nvidia code v14: remove radeon audio hacks - fix up intel resume more like upstream v15: clean up printks + remove unnecessary igd/dis pointers mount debugfs /sys/kernel/debug/vgaswitcheroo/switch - should exist if ATPX detected + 2 cards. DIS - immediate change to discrete IGD - immediate change to IGD DDIS - delayed change to discrete DIGD - delayed change to IGD ON - turn on not in use OFF - turn off not in use Tested on W500 (Intel/ATI) and T500 (Intel/ATI) Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-02-01 13:38:10 +08:00
obj-$(CONFIG_VGA_SWITCHEROO) += vga_switcheroo.o