kernel/git/stable/linux.git/Documentation/filesystems/sysfs-pci.txt, branch master

docs: filesystems: convert sysfs-pci.txt to ReST

2020-05-05T15:22:24+00:00

- Add a SPDX header; - Adjust document title; - Some whitespace fixes and new line breaks; - Mark literal blocks as such; - Add table markups; - Add it to filesystems/index.rst. Signed-off-by: Mauro Carvalho Chehab Link: https://lore.kernel.org/r/2a9d307753c97d1a843341a2ef1993d43a407ded.1588021877.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet

PCI: Add pci_mmap_resource_range() and use it for ARM64

2017-04-20T13:47:47+00:00

Starting to leave behind the legacy of the pci_mmap_page_range() interface which takes "user-visible" BAR addresses. This takes just the resource and offset. For now, both APIs coexist and depending on the platform, one is implemented as a wrapper around the other. Signed-off-by: David Woodhouse Signed-off-by: Bjorn Helgaas

PCI: Add arch_can_pci_mmap_io() on architectures which can mmap() I/O space

2017-04-18T18:02:26+00:00

This is relatively esoteric, and knowing that we don't have it makes life easier in some cases rather than just an eventual -EINVAL from pci_mmap_page_range(). Signed-off-by: David Woodhouse Signed-off-by: Bjorn Helgaas

PCI: Add arch_can_pci_mmap_wc() macro

2017-04-18T18:01:42+00:00

Most of the almost-identical versions of pci_mmap_page_range() silently ignore the 'write_combine' argument and give uncached mappings. Yet we allow the PCIIOC_WRITE_COMBINE ioctl in /proc/bus/pci, expose the 'resourceX_wc' file in sysfs, and allow an attempted mapping to apparently succeed. To fix this, introduce a macro arch_can_pci_mmap_wc() which indicates whether the platform can do a write-combining mapping. On x86 this ends up being pat_enabled(), while the few other platforms that support it can just set it to a literal '1'. Signed-off-by: David Woodhouse Signed-off-by: Bjorn Helgaas

PCI: Create revision file in sysfs

2016-11-21T22:25:32+00:00

Currently the revision isn't available via sysfs/libudev thus if one wants to know the value one needs to read through the config file, which can be quite time-consuming because it wakes/powers up the device. There are at least two userspace components which could make use the new file: libpciaccess and libdrm. The former wakes up _every_ PCI device, which can be observed via glxinfo when using Mesa 10.0+ drivers. The latter, in association with Mesa 13.0, can lead to 2-3 second delays while starting firefox, thunderbird or chromium. Link: https://bugs.freedesktop.org/show_bug.cgi?id=98502 Tested-by: Mauro Santos Signed-off-by: Emil Velikov Signed-off-by: Bjorn Helgaas Reviewed-by: Alex Deucher Reviewed-by: Daniel Vetter

PCI: Allow read/write access to sysfs I/O port resources

2010-07-30T16:32:08+00:00

PCI sysfs resource files currently only allow mmap'ing. On x86 this works fine for memory backed BARs, but doesn't work at all for I/O port backed BARs. Add read/write to I/O port PCI sysfs resource files to allow userspace access to these device regions. Acked-by: Chris Wright Signed-off-by: Alex Williamson Signed-off-by: Jesse Barnes

trivial: Miscellaneous documentation typo fixes

2009-06-12T16:01:47+00:00

Fix various typos in documentation txts. Signed-off-by: Matt LaPlante Signed-off-by: Jiri Kosina

PCI: Introduce /sys/bus/pci/devices/.../remove

2009-03-20T21:58:48+00:00

This patch adds an attribute named "remove" to a PCI device's sysfs directory. Writing a non-zero value to this attribute will remove the PCI device and any children of it. Trent Piepho wrote the original implementation and documentation. Thanks to Vegard Nossum for testing under kmemcheck and finding locking issues with the sysfs interface. Cc: Trent Piepho Tested-by: Vegard Nossum Signed-off-by: Alex Chiang Signed-off-by: Jesse Barnes

PCI: return error on failure to read PCI ROMs

2009-02-05T00:58:41+00:00

This patch makes the ROM reading code return an error to user space if the size of the ROM read is equal to 0. The patch also emits a warnings if the contents of the ROM are invalid, and documents the effects of the "enable" file on ROM reading. Signed-off-by: Timothy S. Nelson Acked-by: Alex Villacis-Lasso Signed-off-by: Jesse Barnes

x86: PAT export resource_wc in pci sysfs

2008-06-12T08:12:42+00:00

For the ranges with IORESOURCE_PREFETCH, export a new resource_wc interface in pci /sysfs along with resource (which is uncached). Signed-off-by: Venkatesh Pallipadi Signed-off-by: Suresh Siddha Acked-by: Jesse Barnes Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner