linux_dsm_epyc7002

mirror of https://github.com/AuxXxilium/linux_dsm_epyc7002.git synced 2024-12-28 11:18:45 +07:00

History

Jiri Kosina c12aba5aa0 drm/i915: stop using GMBUS IRQs on Gen4 chips Commit `28c70f162` ("drm/i915: use the gmbus irq for waits") switched to using GMBUS irqs instead of GPIO bit-banging for chipset generations 4 and above. It turns out though that on many systems this leads to spurious interrupts being generated, long after the register write to disable the IRQs has been issued. Typically this results in the spurious interrupt source getting disabled: [ 9.636345] irq 16: nobody cared (try booting with the "irqpoll" option) [ 9.637915] Pid: 4157, comm: ifup Tainted: GF 3.9.0-rc2-00341-g0863702 #422 [ 9.639484] Call Trace: [ 9.640731] <IRQ> [<ffffffff8109b40d>] __report_bad_irq+0x1d/0xc7 [ 9.640731] [<ffffffff8109b7db>] note_interrupt+0x15b/0x1e8 [ 9.640731] [<ffffffff810999f7>] handle_irq_event_percpu+0x1bf/0x214 [ 9.640731] [<ffffffff81099a88>] handle_irq_event+0x3c/0x5c [ 9.640731] [<ffffffff8109c139>] handle_fasteoi_irq+0x7a/0xb0 [ 9.640731] [<ffffffff8100400e>] handle_irq+0x1a/0x24 [ 9.640731] [<ffffffff81003d17>] do_IRQ+0x48/0xaf [ 9.640731] [<ffffffff8142f1ea>] common_interrupt+0x6a/0x6a [ 9.640731] <EOI> [<ffffffff8142f952>] ? system_call_fastpath+0x16/0x1b [ 9.640731] handlers: [ 9.640731] [<ffffffffa000d771>] usb_hcd_irq [usbcore] [ 9.640731] [<ffffffffa0306189>] yenta_interrupt [yenta_socket] [ 9.640731] Disabling IRQ #16 The really curious thing is now that irq 16 is _not_ the interrupt for the i915 driver when using MSI, but it _is_ the interrupt when not using MSI. So by all indications it seems like gmbus is able to generate a legacy (shared) interrupt in MSI mode on some configurations. I've tried to reproduce this and the differentiating thing seems to be that on unaffected systems no other device uses irq 16 (which seems to be the non-MSI intel gfx interrupt on all gm45). I have no idea how that even can happen. To avoid tempting this elephant into a rage, just disable gmbus interrupt support on gen 4. v2: Improve the commit message with exact details of what's going on. Also add a comment in the code to warn against this particular elephant in the room. v3: Move the comment explaing how gen4 blows up next to the definition of HAS_GMBUS_IRQ to keep the code-flow straight. Suggested by Chris Wilson. Signed-off-by: Jiri Kosina <jkosina@suse.cz> (v1) Acked-by: Chris Wilson <chris@chris-wilson.co.uk> References: https://lkml.org/lkml/2013/3/8/325 Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>		2013-03-20 00:03:16 +01:00
..
ast
cirrus
exynos
gma500
i2c
i810
i915	drm/i915: stop using GMBUS IRQs on Gen4 chips	2013-03-20 00:03:16 +01:00
mga
mgag200	drm/mgag200: Bug fix: Renesas board now selects native resolution.	2013-03-08 08:31:49 +10:00
nouveau	drm/nv50-: prevent some races between modesetting and page flipping	2013-03-04 11:46:35 +10:00
omapdrm
r128
radeon	drm/radeon: don't check mipmap alignment if MIP_ADDRESS is FMASK	2013-03-07 12:58:59 -05:00
savage
shmobile
sis
tdfx
tegra	drm/tegra: drop "select DRM_HDMI"	2013-03-08 08:36:01 +10:00
tilcdc
ttm
udl
via
vmwgfx
ati_pcigart.c
drm_agpsupport.c
drm_auth.c
drm_buffer.c
drm_bufs.c
drm_cache.c
drm_context.c
drm_crtc_helper.c
drm_crtc.c
drm_debugfs.c
drm_dma.c
drm_dp_helper.c
drm_drv.c
drm_edid_load.c
drm_edid.c
drm_encoder_slave.c
drm_fb_cma_helper.c
drm_fb_helper.c
drm_fops.c
drm_gem_cma_helper.c
drm_gem.c
drm_global.c
drm_hashtab.c
drm_info.c
drm_ioc32.c
drm_ioctl.c
drm_irq.c
drm_lock.c
drm_memory.c
drm_mm.c
drm_modes.c
drm_pci.c
drm_platform.c
drm_prime.c
drm_proc.c
drm_scatter.c
drm_stub.c
drm_sysfs.c
drm_trace_points.c
drm_trace.h
drm_usb.c
drm_vm.c
Kconfig
Makefile
README.drm

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