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: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The patch uses eeh_unfreeze_pe() to replace the logic clearing
frozen IO and DMA, in order to simplify the code.
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

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: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

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: NWei Yang <weiyang@linux.vnet.ibm.com>
Acked-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

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: NGavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

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: NGavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The patch moves the common part of EEH core into arch/powerpc/kernel
directory so that we needn't PPC_PSERIES while compiling POWERNV
platform:

        * Move the EEH common part into arch/powerpc/kernel
        * Move the functions for PCI hotplug from pSeries platform to
          arch/powerpc/kernel/pci-hotplug.c
        * Move CONFIG_EEH from arch/powerpc/platforms/pseries/Kconfig to
          arch/powerpc/platforms/Kconfig
        * Adjust makefile accordingly
Signed-off-by: NGavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The patch removes the eeh related statistics for eeh device since
they have been maintained by the corresponding eeh PE. Also, the
flags used to trace the state of eeh device and PE have been reworked
for a little bit.
Signed-off-by: NGavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

With original EEH implementation, all EEH related statistics have
been put into struct pci_dn. We've introduced struct eeh_dev to
replace struct pci_dn in EEH core components, including EEH sysfs
component.

The patch shows EEH statistics from struct eeh_dev instead of struct
pci_dn in EEH sysfs component. Besides, it also fixed the EEH device
retrieval from PCI device, which was introduced by the previous patch
in the series of patch.
Signed-off-by: NGavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

There're several EEH aux components and the patch does some cleanup
for them so that they look more clean.

        * Duplicated comments have been removed from the header file.
        * Comments have been reorganized so that it looks more clean.
        * The leading comments of functions are adjusted for a little
          bit so that the result of "make pdfdocs" would be more
          unified.
        * Function calls "xxx ()" has been replaced by "xxx()".
Signed-off-by: NGavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

They get it via module.h (via device.h) but we want to clean that up.
When we do, we'll get things like:

ibmebus.c:314: error: 'S_IWUSR' undeclared here (not in a function)
vio.c:972: error: 'S_IWUSR' undeclared here (not in a function)

so add in the stat header it is using explicitly in advance.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

Remove kobject.h from files which don't need it, notably,
sched.h and fs.h.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Track and report the number of times we read an all-1s value (0xff,
0xffff or 0xffffffff) from each device which is valid data, not
indicating EEH isolation.
Signed-off-by: NLinas Vepstas <linas@austin.ibm.com>

----
 arch/powerpc/platforms/pseries/eeh.c       |    5 +++++
 arch/powerpc/platforms/pseries/eeh_sysfs.c |    3 +++
 include/asm-powerpc/pci-bridge.h           |    1 +
 3 files changed, 9 insertions(+)
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Add sysfs blinkenlights for EEH statistics.  Shuffle the
eeh_add_device_tree() call so that it appears in the correct
sequence.
Signed-off-by: NLinas Vepstas <linas@austin.ibm.com>

----
 arch/powerpc/platforms/pseries/Makefile    |    2
 arch/powerpc/platforms/pseries/eeh.c       |    4 +
 arch/powerpc/platforms/pseries/eeh_cache.c |    2
 arch/powerpc/platforms/pseries/eeh_sysfs.c |   84 +++++++++++++++++++++++++++++
 arch/powerpc/platforms/pseries/pci_dlpar.c |    7 +-
 include/asm-powerpc/ppc-pci.h              |    3 +
 6 files changed, 98 insertions(+), 4 deletions(-)
Signed-off-by: NPaul Mackerras <paulus@samba.org>