Diagnostic data for PHBs currently works by allocated a fixed-sized buffer.
This is simple, but either wastes memory (though only a few kilobytes) or
in the case of PHB4 isn't enough to fit the whole data blob.

For machines that don't describe the diagnostic data size in the device
tree, use the hardcoded buffer size as before.  For those that do, only
allocate exactly what's needed.

In the special case of P7IOC (which has two types of diag data), the larger
should be specified in the device tree.
Signed-off-by: NRussell Currey <ruscur@russell.cc>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Similar to what is done in commit b6541db1 ("powerpc/eeh: Block
PCI config access upon frozen PE"), we need block PCI config access
for BCM5719 when recovering frozen error on them. Otherwise, an
unexpected recursive fenced PHB error is observed.

   0001:06:00.0 Ethernet controller: Broadcom Corporation \
                NetXtreme BCM5718 Gigabit Ethernet PCIe (rev 10)
   0001:06:00.1 Ethernet controller: Broadcom Corporation \
                NetXtreme BCM5718 Gigabit Ethernet PCIe (rev 10)
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

pnv_eeh_reset() has special handling for PEs whose primary bus is the
root bus or the bus immediately underneath the root port.

The cxl bi-modal card support added in b0b5e591 ("cxl: Add
cxl_check_and_switch_mode() API to switch bi-modal cards") relies on
this behaviour when hot-resetting the CAPI adapter following a mode
switch.  Document this in pnv_eeh_reset() so we don't accidentally break
it.
Suggested-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

PHB, PE (and by association MVE) numbers are printed as a mix of decimal
and hexadecimal throughout the kernel.  This can be misleading, so make
them all hexadecimal.

Standardising on hex instead of dec because:

 - PHB numbers are presented in hex in sysfs/debugfs (and lspci, etc)
 - PE numbers are presented as hex in sysfs and parsed in hex in debugfs

The only place I think this could cause confusing are the messages during
boot, i.e.

	pci 000a:01     : [PE# 000] Secondary bus 1 associated with PE#0

which can be a quick way to check PE numbers.  pe_level_printk() will
only print two characters instead of three, so the above would be

	pci 000a:01     : [PE# 00] Secondary bus 1 associated with PE#0

which gives a hint it's in hex.
Signed-off-by: NRussell Currey <ruscur@russell.cc>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The hub diag-data type is filled with big-endian data by OPAL call
opal_pci_get_hub_diag_data(). We need convert it to CPU-endian value
before using it. The issue is reported by sparse as pointed by Michael
Ellerman:

  eeh-powernv.c:1309:21: warning: restricted __be16 degrades to integer

This converts hub diag-data type to CPU-endian before using it in
pnv_eeh_get_and_dump_hub_diag().

Fixes: 2a485ad7 ("powerpc/powernv: Drop PHB operation next_error()")
Cc: stable@vger.kernel.org # v4.1+
Suggested-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: NRussell Currey <ruscur@russell.cc>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The PE number (@frozen_pe_no), filled by opal_pci_next_error() is in
big-endian format. It should be converted to CPU-endian before it is
passed to opal_pci_eeh_freeze_clear() when clearing the frozen state if
the PE is invalid one. As Michael Ellerman pointed out, the issue is
also detected by sparse:

  eeh-powernv.c:1541:41: warning: incorrect type in argument 2 (different base types)

This passes CPU-endian PE number to opal_pci_eeh_freeze_clear() and it
should be part of commit <0f36db77> ("powerpc/eeh: Fix wrong printed
PE number"), which was merged to 4.3 kernel.

Fixes: 71b540ad ("powerpc/powernv: Don't escalate non-existing frozen PE")
Cc: stable@vger.kernel.org # v4.3+
Suggested-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: NRussell Currey <ruscur@russell.cc>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

When issuing PHB reset, OPAL API opal_pci_poll() is called to drive
the state machine in OPAL forward. However, we needn't always call
the function under some circumstances like reset deassert.

This avoids calling opal_pci_poll() when OPAL_SUCCESS is returned
from opal_pci_reset(). Except the overhead introduced by additional
one unnecessary OPAL call, I didn't run into real issue because of
this.
Reported-by: NPridhiviraj Paidipeddi <ppaiddipe@in.ibm.com>
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

When the PE used in pnv_eeh_reset() is that of a VF,
pnv_eeh_reset_vf_pe() is used.  Unlike the other reset functions called
in pnv_eeh_reset(), the VF reset doesn't require a bus, and if a bus was
missing the function would error out before resetting the VF PE.

To avoid this, reorder the VF reset function to occur before finding and
checking the bus.
Signed-off-by: NRussell Currey <ruscur@russell.cc>
Reviewed-by: NAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

eeh_pe_bus_get() can return NULL if a PCI bus isn't found for a given PE.
Some callers don't check this, and can cause a null pointer dereference
under certain circumstances.

Fix this by checking NULL everywhere eeh_pe_bus_get() is called.

Fixes: 8a6b1bc7 ("powerpc/eeh: EEH core to handle special event")
Cc: stable@vger.kernel.org # v3.11+
Signed-off-by: NRussell Currey <ruscur@russell.cc>
Reviewed-by: NAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The (OPAL) firmware might provide the PCI slot reset capability
which is identified by property "ibm,reset-by-firmware" on the
PCI slot associated device node.

This routes the reset request to firmware if "ibm,reset-by-firmware"
exists in the PCI slot device node. Otherwise, the reset is done
inside kernel as before.
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The reset and poll functionality from (OPAL) firmware supports
PHB and PCI slot at same time. They are identified by ID. This
supports PCI slot ID by:

   * Rename the argument name for opal_pci_reset() and opal_pci_poll()
     accordingly
   * Rename pnv_eeh_phb_poll() to pnv_eeh_poll() and adjust its argument
     name.
   * One macro is added to produce PCI slot ID.
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This reverts commit c8ceacc2.

Gavin says: I missed the fact that it affects the PCI passthrou path as
reported by Alexey: When passing GPU (0003:01:00.0) which seats behind
the root port, the reset request is routed to skiboot in original code.
In skiboot, the link bouncing events are masked during the reset. So we
don't see EEH (freeze all) error even link bouncing happens. With the
changes included, the reset is done by kernel and the link bouncing
events aren't masked by altering content of PHB3 (or P7IOC) specific
hardware registers which are invisible to kernel (skiboot hides the
hardware specific). It means the link bouncing is seen by the root port
and it causes a EEH (freeze all) error. The PCI passthrough on GPU
device cannot work.
Requested-by: NAlexey Kardashevskiy <aik@ozlabs.ru>
Requested-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The function pnv_pci_reset_secondary_bus() is called like below.
It's impossible for call the function on root bus. So it's safe
to remove the root bus case in the function. No functional changes
introduced.

   pci_parent_bus_reset() / pci_bus_reset() / pci_try_reset_bus()
   pci_reset_bridge_secondary_bus()
   pcibios_reset_secondary_bus()
   pnv_pci_reset_secondary_bus()
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: NDaniel Axtens <dja@axtens.net>
Reviewed-by: NAlexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This drops unnecessary nested if statements in pnv_eeh_reset() to
improve the code readability. After the changes, the unused local
variable "ret" is dropped as well. No logical changes introduced.
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: NAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: NAlexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This renames the fields related to PE number in "struct pnv_phb"
for better reflecting of their usages as Alexey suggested. No
logical changes introduced.
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: NAlexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

After PE reset, OPAL API opal_pci_reinit() is called on all devices
contained in the PE to reinitialize them. While skiboot is not aware of
VFs, we have to implement the function in kernel to reinitialize VFs after
reset on PE for VFs.

In this patch, two functions pnv_pci_fixup_vf_mps() and
pnv_eeh_restore_vf_config() both manipulate the MPS of the VF, since for a
VF it has three cases.

1. Normal creation for a VF
   In this case, pnv_pci_fixup_vf_mps() is called to make the MPS a proper
   value compared with its parent.
2. EEH recovery without VF removed
   In this case, MPS is stored in pci_dn and pnv_eeh_restore_vf_config() is
   called to restore it and reinitialize other part.
3. EEH recovery with VF removed
   In this case, VF will be removed then re-created. Both functions are
   called. First pnv_pci_fixup_vf_mps() is called to store the proper MPS
   to pci_dn and then pnv_eeh_restore_vf_config() is called to do proper
   thing.

This introduces two functions: pnv_pci_fixup_vf_mps() to fixup the VF's
MPS to make sure it is equal to parent's and store this value in pci_dn
for future use. pnv_eeh_restore_vf_config() to re-initialize on VF by
restoring MPS, disabling completion timeout, enabling SERR, etc.
Signed-off-by: NWei Yang <weiyang@linux.vnet.ibm.com>
Acked-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

PEs for VFs don't have primary bus. So they have to have their own reset
backend, which is used during EEH recovery. The patch implements the reset
backend for VF's PE by issuing FLR or AF FLR to the VFs, which are contained
in the PE.
Signed-off-by: NWei Yang <weiyang@linux.vnet.ibm.com>
Acked-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This creates PEs for VFs in the weak function pcibios_bus_add_device().
Those PEs for VFs are identified with newly introduced flag EEH_PE_VF
so that we treat them differently during EEH recovery.
Signed-off-by: NWei Yang <weiyang@linux.vnet.ibm.com>
Acked-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

When PE is created, its primary bus is cached to pe->bus. At later
point, the cached primary bus is returned from eeh_pe_bus_get().
However, we could get stale cached primary bus and run into kernel
crash in one case: full hotplug as part of fenced PHB error recovery
releases all PCI busses under the PHB at unplugging time and recreate
them at plugging time. pe->bus is still dereferencing the PCI bus
that was released.

This adds another PE flag (EEH_PE_PRI_BUS) to represent the validity
of pe->bus. pe->bus is updated when its first child EEH device is
online and the flag is set. Before unplugging in full hotplug for
error recovery, the flag is cleared.

Fixes: 8cdb2833 ("powerpc/eeh: Trace PCI bus from PE")
Cc: stable@vger.kernel.org #v3.11+
Reported-by: NAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Reported-by: NPradipta Ghosh <pradghos@in.ibm.com>
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Tested-by: NAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The EEH debugfs handlers have same prototype. This introduces
a macro to define them, then to simplify the code. No logical
changes.
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Long ago, only in the lab, there was OPALv1 and OPALv2. Now there is
just OPALv3, with nobody ever expecting anything on pre-OPALv3 to
be cared about or supported by mainline kernels.

So, let's remove FW_FEATURE_OPALv3 and instead use FW_FEATURE_OPAL
exclusively.
Signed-off-by: NStewart Smith <stewart@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Similar to commit b6541db1 ("powerpc/eeh: Block PCI config access
upon frozen PE"), this blocks the PCI config space of Broadcom
Shiner adapter until PE reset is completed, to avoid recursive
fenced PHB when dumping PCI config registers during the period
of error recovery.

   ~# lspci -ns 0003:03:00.0
   0003:03:00.0 0200: 14e4:168a (rev 10)
   ~# lspci -s 0003:03:00.0
   0003:03:00.0 Ethernet controller: Broadcom Corporation \
                NetXtreme II BCM57800 1/10 Gigabit Ethernet (rev 10)
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This simplifies pnv_eeh_set_option() to avoid unnecessary nested
if statements, to improve readability. No functional changes.
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: NAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This moves the logic of pnv_eeh_cap_start() to pnv_eeh_find_cap()
as the function is only called by pnv_eeh_find_cap(). The logic
of both functions are pretty simple. No need to have separate
functions.
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: NAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This applies cleanup on eeh-powernv.c, no functional changes:

   * Remove unnecessary comments and empty line.
   * Correct inaccurate comments.
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

pnv_eeh_next_error() re-enables the eeh opal event interrupt but it
gets called from a loop if there are more outstanding events to
process, resulting in a warning due to enabling an already enabled
interrupt. Instead the interrupt should only be re-enabled once the
last outstanding event has been processed.
Tested-by: NDaniel Axtens <dja@axtens.net>
Reported-by: NDaniel Axtens <dja@axtens.net>
Signed-off-by: NAlistair Popple <alistair@popple.id.au>
Acked-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

When detecting EEH error on non-existing PE, including the reserved
one, the PE is simply unfrozen without dumping the PHB diag-data,
which is useful for locating the root cause of the EEH error. The
patch dumps the PHB diag-data when non-existing PE reports error.
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

On LE kernel, the non-existing PE number in BE format derived from
skiboot firmware isn't converted to LE format properly as following
kernel log indicates:

   EEH: Clear non-existing PHB#4-PE#200000000000000
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The eeh code currently uses the old notifier method to get eeh events
from OPAL. It also contains some logic to filter opal events which has
been moved into the virtual irqchip. This patch converts the eeh code
to the new event interface which simplifies event handling.
Signed-off-by: NAlistair Popple <alistair@popple.id.au>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

As the comment indicates, powernv_eeh_get_state() will inform EEH core to
delay 1 second. This means the delay doesn't happen when
powernv_eeh_get_state() returns.

This patch moves the delay subtraction just before msleep(), which is the
same logic in pseries_eeh_wait_state().
Signed-off-by: NWei Yang <weiyang@linux.vnet.ibm.com>
Acked-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

To retrieve the PCI slot state, EEH driver would set a timeout for that.
While current comment is not aligned to what the code does.

This patch fixes those comments according to the code.
Signed-off-by: NWei Yang <weiyang@linux.vnet.ibm.com>
Acked-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

There are 3 EEH operations whose arguments contain device_node:
read_config(), write_config() and restore_config(). The patch
replaces device_node with pci_dn.
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Originally, EEH core probes on device_node or pci_dev to populate
EEH devices and PEs, which conflicts with the fact: SRIOV VFs are
usually enabled and created by PF's driver and they don't have the
corresponding device_nodes. Instead, SRIOV VFs have dynamically
created pci_dn, which can be used for EEH probe.

The patch reworks EEH probe for PowerNV and pSeries platforms to
do probing based on pci_dn, instead of pci_dev or device_node any
more.
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The PCI config accessors previously relied on device_node.  Unfortunately,
VFs don't have a corresponding device_node, so change the accessors to use
pci_dn instead.

[bhelgaas: changelog]
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The patch drops PHB EEH operation reset() and merges its logic to
eeh_ops::reset().
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The patch drops PHB EEH operation next_error() and merges its
logic to eeh_ops::next_error().
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The patch drops PHB EEH operation get_state() and merges its logic
to eeh_ops::get_state().
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The patch drops PHB EEH operation set_option() and merges its
logic to eeh_ops::set_option().
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The patch drops PHB EEH operation configure_bridge() and merges
its logic to eeh_ops::configure_bridge().
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The patch drops PHB operation get_log() and merges its logic to
eeh_ops::get_log().
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>