linux.git/arch/powerpc/kernel/eeh_sysfs.c, branch v4.18

powerpc/eeh: Add EEH notify resume sysfs

2018-01-27T09:02:52+00:00

Introduce a method for notify resume to be called from sysfs. In this
patch one can now call notify resume from sysfs when is supported by
platform.

Signed-off-by: Bryant G. Ly 
Signed-off-by: Juan J. Alvarez 
Acked-by: Russell Currey 
[mpe: Add NULL check, add empty versions to avoid #ifdefs]
Signed-off-by: Michael Ellerman

powerpc: Use octal numbers for file permissions

2018-01-21T18:48:33+00:00

Symbolic macros are unintuitive and hard to read, whereas octal constants
are much easier to interpret.  Replace macros for the basic permission
flags (user/group/other read/write/execute) with numeric constants
instead, across the whole powerpc tree.

Introducing a significant number of changes across the tree for no runtime
benefit isn't exactly desirable, but so long as these macros are still
used in the tree people will keep sending patches that add them.  Not only
are they hard to parse at a glance, there are multiple ways of coming to
the same value (as you can see with 0444 and 0644 in this patch) which
hurts readability.

Signed-off-by: Russell Currey 
Reviewed-by: Cyril Bur 
Signed-off-by: Michael Ellerman

powerpc/eeh: Remove unnecessary config_addr from eeh_dev

2017-08-31T04:26:09+00:00

The eeh_dev struct hold a config space address of an associated node
and the very same address is also stored in the pci_dn struct which
is always present during the eeh_dev lifetime.

This uses bus:devfn directly from pci_dn instead of cached and packed
config_addr.

Since config_addr is made from device's bus:dev.fn, there is no point
in keeping it in the debugfs either so remove that too.

Signed-off-by: Alexey Kardashevskiy 
Signed-off-by: Michael Ellerman

powerpc/eeh: Fix PE state format

2014-11-26T22:32:58+00:00

Obviously I had wrong format given to the PE state output from
/sys/bus/pci/devices/xxxx/eeh_pe_state with some typoes, which
was introduced by commit 2013add4ce73. The patch fixes it up.

Fixes: 2013add4ce73 ("powerpc/eeh: Show hex prefix for PE state sysfs")
Signed-off-by: Gavin Shan 
Signed-off-by: Michael Ellerman

powerpc/eeh: Show hex prefix for PE state sysfs

2014-10-01T12:23:34+00:00

As Michael suggested, the hex prefix for the output of EEH PE
state sysfs entry (/sys/bus/pci/devices/xxx/eeh_pe_state) is
always informative to users.

Suggested-by: Michael Ellerman 
Signed-off-by: Gavin Shan 
Signed-off-by: Michael Ellerman

powerpc/eeh: Use eeh_unfreeze_pe()

2014-09-30T07:15:14+00:00

The patch uses eeh_unfreeze_pe() to replace the logic clearing
frozen IO and DMA, in order to simplify the code.

Signed-off-by: Gavin Shan 
Signed-off-by: Michael Ellerman

powerpc/eeh: Add eeh_pe_state sysfs entry

2014-09-30T07:15:06+00:00

The patch adds sysfs entry "eeh_pe_state". Reading on it returns
the PE's state while writing to it clears the frozen state. It's
used to check or clear the PE frozen state from userland for
debugging purpose.

The patch also replaces printk(KERN_WARNING ...) with pr_warn() in
eeh_sysfs.c

Signed-off-by: Gavin Shan 
Signed-off-by: Michael Ellerman

powerpc/eeh: Skip eeh sysfs when eeh is disabled

2014-06-05T03:20:38+00:00

When eeh is not enabled, and hotplug two pci devices on the same bus, eeh
related sysfs would be added twice for the first added pci device. Since the
eeh_dev is not created when eeh is not enabled.

This patch adds the check, if eeh is not enabled, eeh sysfs will not be
created.

After applying this patch, following warnings are reduced:

sysfs: cannot create duplicate filename '/devices/pci0000:00/0000:00:00.0/eeh_mode'
sysfs: cannot create duplicate filename '/devices/pci0000:00/0000:00:00.0/eeh_config_addr'
sysfs: cannot create duplicate filename '/devices/pci0000:00/0000:00:00.0/eeh_pe_config_addr'

Signed-off-by: Wei Yang 
Acked-by: Gavin Shan 
Signed-off-by: Benjamin Herrenschmidt

powerpc/eeh: Introdce flag to protect sysfs

2013-07-24T04:18:49+00:00

The patch introduces flag EEH_DEV_SYSFS to keep track that the sysfs
entries for the corresponding EEH device (then PCI device) has been
added or removed, in order to avoid race condition.

Signed-off-by: Gavin Shan 
Signed-off-by: Benjamin Herrenschmidt

powerpc/eeh: Use partial hotplug for EEH unaware drivers

2013-07-24T04:18:48+00:00

When EEH error happens to one specific PE, some devices with drivers
supporting EEH won't except hotplug on the device. However, there
might have other deivces without driver, or with driver without EEH
support. For the case, we need do partial hotplug in order to make
sure that the PE becomes absolutely quite during reset. Otherise,
the PE reset might fail and leads to failure of error recovery.

The current code doesn't handle that 'mixed' case properly, it either
uses the error callbacks to the drivers, or tries hotplug, but doesn't
handle a PE (EEH domain) composed of a combination of the two.

The patch intends to support so-called "partial" hotplug for EEH:
Before we do reset, we stop and remove those PCI devices without
EEH sensitive driver. The corresponding EEH devices are not detached
from its PE, but with special flag. After the reset is done, those
EEH devices with the special flag will be scanned one by one.

Signed-off-by: Gavin Shan 
Signed-off-by: Benjamin Herrenschmidt