powerpc/pseries/iommu: DLPAR add doesn't completely initialize pci_controller

When a PCI device is dynamically added, the kernel oopses with a NULL
pointer dereference:

BUG: Kernel NULL pointer dereference on read at 0x00000030
Faulting instruction address: 0xc0000000006bbe5c
Oops: Kernel access of bad area, sig: 11 [#1]
LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries
Modules linked in: rpadlpar_io rpaphp rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache netfs xsk_diag bonding nft_compat nf_tables nfnetlink rfkill binfmt_misc dm_multipath rpcrdma sunrpc rdma_ucm ib_srpt ib_isert iscsi_target_mod target_core_mod ib_umad ib_iser libiscsi scsi_transport_iscsi ib_ipoib rdma_cm iw_cm ib_cm mlx5_ib ib_uverbs ib_core pseries_rng drm drm_panel_orientation_quirks xfs libcrc32c mlx5_core mlxfw sd_mod t10_pi sg tls ibmvscsi ibmveth scsi_transport_srp vmx_crypto pseries_wdt psample dm_mirror dm_region_hash dm_log dm_mod fuse
CPU: 17 PID: 2685 Comm: drmgr Not tainted 6.7.0-203405+ #66
Hardware name: IBM,9080-HEX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1060.00 (NH1060_008) hv:phyp pSeries
NIP: c0000000006bbe5c LR: c000000000a13e68 CTR: c0000000000579f8
REGS: c00000009924f240 TRAP: 0300 Not tainted (6.7.0-203405+)
MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE> CR: 24002220 XER: 20040006
CFAR: c000000000a13e64 DAR: 0000000000000030 DSISR: 40000000 IRQMASK: 0
...
NIP sysfs_add_link_to_group+0x34/0x94
LR iommu_device_link+0x5c/0x118
Call Trace:
iommu_init_device+0x26c/0x318 (unreliable)
iommu_device_link+0x5c/0x118
iommu_init_device+0xa8/0x318
iommu_probe_device+0xc0/0x134
iommu_bus_notifier+0x44/0x104
notifier_call_chain+0xb8/0x19c
blocking_notifier_call_chain+0x64/0x98
bus_notify+0x50/0x7c
device_add+0x640/0x918
pci_device_add+0x23c/0x298
of_create_pci_dev+0x400/0x884
of_scan_pci_dev+0x124/0x1b0
__of_scan_bus+0x78/0x18c
pcibios_scan_phb+0x2a4/0x3b0
init_phb_dynamic+0xb8/0x110
dlpar_add_slot+0x170/0x3b8 [rpadlpar_io]
add_slot_store.part.0+0xb4/0x130 [rpadlpar_io]
kobj_attr_store+0x2c/0x48
sysfs_kf_write+0x64/0x78
kernfs_fop_write_iter+0x1b0/0x290
vfs_write+0x350/0x4a0
ksys_write+0x84/0x140
system_call_exception+0x124/0x330
system_call_vectored_common+0x15c/0x2ec

Commit a940904443e4 ("powerpc/iommu: Add iommu_ops to report capabilities
and allow blocking domains") broke DLPAR add of PCI devices.

The above added iommu_device structure to pci_controller. During
system boot, PCI devices are discovered and this newly added iommu_device
structure is initialized by a call to iommu_device_register().

During DLPAR add of a PCI device, a new pci_controller structure is
allocated but there are no calls made to iommu_device_register()
interface.

Fix is to register the iommu device during DLPAR add as well.

Fixes: a940904443e4 ("powerpc/iommu: Add iommu_ops to report capabilities and allow blocking domains")
Signed-off-by: Gaurav Batra <gbatra@linux.ibm.com>
Reviewed-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240215221833.4817-1-gbatra@linux.ibm.com

Revert "powerpc/pseries/iommu: Fix iommu initialisation during DLPAR add"

This reverts commit ed8b94f6e0acd652ce69bd69d678a0c769172df8.

Gaurav reported that there are still problems with the patch and it
should be reverted pending a fuller fix.

Link: https://lore.kernel.org/all/4f6fc1ac-7a76-4447-9d0e-f55c0be373f8@linux.ibm.com/
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/pseries/iommu: Fix iommu initialisation during DLPAR add

When a PCI device is dynamically added, the kernel oopses with a NULL
pointer dereference:

BUG: Kernel NULL pointer dereference on read at 0x00000030
Faulting instruction address: 0xc0000000006bbe5c
Oops: Kernel access of bad area, sig: 11 [#1]
LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries
Modules linked in: rpadlpar_io rpaphp rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache netfs xsk_diag bonding nft_compat nf_tables nfnetlink rfkill binfmt_misc dm_multipath rpcrdma sunrpc rdma_ucm ib_srpt ib_isert iscsi_target_mod target_core_mod ib_umad ib_iser libiscsi scsi_transport_iscsi ib_ipoib rdma_cm iw_cm ib_cm mlx5_ib ib_uverbs ib_core pseries_rng drm drm_panel_orientation_quirks xfs libcrc32c mlx5_core mlxfw sd_mod t10_pi sg tls ibmvscsi ibmveth scsi_transport_srp vmx_crypto pseries_wdt psample dm_mirror dm_region_hash dm_log dm_mod fuse
CPU: 17 PID: 2685 Comm: drmgr Not tainted 6.7.0-203405+ #66
Hardware name: IBM,9080-HEX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1060.00 (NH1060_008) hv:phyp pSeries
NIP: c0000000006bbe5c LR: c000000000a13e68 CTR: c0000000000579f8
REGS: c00000009924f240 TRAP: 0300 Not tainted (6.7.0-203405+)
MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE> CR: 24002220 XER: 20040006
CFAR: c000000000a13e64 DAR: 0000000000000030 DSISR: 40000000 IRQMASK: 0
...
NIP sysfs_add_link_to_group+0x34/0x94
LR iommu_device_link+0x5c/0x118
Call Trace:
iommu_init_device+0x26c/0x318 (unreliable)
iommu_device_link+0x5c/0x118
iommu_init_device+0xa8/0x318
iommu_probe_device+0xc0/0x134
iommu_bus_notifier+0x44/0x104
notifier_call_chain+0xb8/0x19c
blocking_notifier_call_chain+0x64/0x98
bus_notify+0x50/0x7c
device_add+0x640/0x918
pci_device_add+0x23c/0x298
of_create_pci_dev+0x400/0x884
of_scan_pci_dev+0x124/0x1b0
__of_scan_bus+0x78/0x18c
pcibios_scan_phb+0x2a4/0x3b0
init_phb_dynamic+0xb8/0x110
dlpar_add_slot+0x170/0x3b8 [rpadlpar_io]
add_slot_store.part.0+0xb4/0x130 [rpadlpar_io]
kobj_attr_store+0x2c/0x48
sysfs_kf_write+0x64/0x78
kernfs_fop_write_iter+0x1b0/0x290
vfs_write+0x350/0x4a0
ksys_write+0x84/0x140
system_call_exception+0x124/0x330
system_call_vectored_common+0x15c/0x2ec

Commit a940904443e4 ("powerpc/iommu: Add iommu_ops to report capabilities
and allow blocking domains") broke DLPAR add of PCI devices.

The above added iommu_device structure to pci_controller. During
system boot, PCI devices are discovered and this newly added iommu_device
structure is initialized by a call to iommu_device_register().

During DLPAR add of a PCI device, a new pci_controller structure is
allocated but there are no calls made to iommu_device_register()
interface.

Fix is to register the iommu device during DLPAR add as well.

Fixes: a940904443e4 ("powerpc/iommu: Add iommu_ops to report capabilities and allow blocking domains")
Signed-off-by: Gaurav Batra <gbatra@linux.ibm.com>
[mpe: Trim oops and tweak some change log wording]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240122222407.39603-1-gbatra@linux.ibm.com

powerpc/rtas_pci: rename and properly expose config access APIs

The rtas_read_config() and rtas_write_config() functions in
kernel/rtas_pci.c have external linkage and two users in arch/powerpc:
the rtas_pci code itself and the pseries platform's "enhanced error
handling" (EEH) support code.

The prototypes for these functions in asm/ppc-pci.h have until now
been guarded by CONFIG_EEH since the only external caller is the
pseries EEH code. However, this presumably has always generated
warnings when built with !CONFIG_EEH and -Wmissing-prototypes:

arch/powerpc/kernel/rtas_pci.c:46:5: error: no previous prototype for
function 'rtas_read_config' [-Werror,-Wmissing-prototypes]
46 | int rtas_read_config(struct pci_dn *pdn, int where,
int size, u32 *val)

arch/powerpc/kernel/rtas_pci.c:98:5: error: no previous prototype for
function 'rtas_write_config' [-Werror,-Wmissing-prototypes]
98 | int rtas_write_config(struct pci_dn *pdn, int where,
int size, u32 val)

The introduction of commit c6345dfa6e3e ("Makefile.extrawarn: turn on
missing-prototypes globally") forces the issue.

The efika and chrp platform code have (static) functions with the same
names but different signatures. We may as well eliminate the potential
for conflicts and confusion by renaming the globally visible versions
as their prototypes get moved out of the CONFIG_EEH-guarded region;
their current names are too generic anyway. Since they operate on
objects of the type 'struct pci_dn *', give them the slightly more
verbose prefix "rtas_pci_dn_" and fix up all the call sites.

Fixes: c6345dfa6e3e ("Makefile.extrawarn: turn on missing-prototypes globally")
Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
Closes: https://lore.kernel.org/linuxppc-dev/CA+G9fYt0LLXtjSz+Hkf3Fhm-kf0ZQanrhUS+zVZGa3O+Wt2+vg@mail.gmail.com/
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231127-rtas-pci-rw-config-v1-1-385d29ace3df@linux.ibm.com

powerpc/fsl_uli1575: Mark uli_exclude_device() as static

Function uli_exclude_device() is not used outside of the fsl_uli1575.c
source file anymore. So mark it as static and remove public prototype.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230409000812.18904-9-pali@kernel.org

powerpc/85xx: mpc85xx_ds: Move uli_init() code into its own driver file

Move uli_init() function into existing driver fsl_uli1575.c file in order
to share its code between more platforms and board files.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230409000812.18904-5-pali@kernel.org

powerpc/fsl_uli1575: Misc cleanup

Use a single line for uli_exclude_device().

Add uli_exclude_device() prototype in ppc-pci.h and guard it.

Remove that prototype from mpc85xx_ds.c and mpc86xx_hpcn.c files.

Make uli_pirq_to_irq[] static as it is used only in that file.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230409000812.18904-2-pali@kernel.org

powerpc/eeh: Use dev_driver_string() instead of struct pci_dev->driver->name

Replace pdev->driver->name by dev_driver_string() for the corresponding
struct device. This is a step toward removing pci_dev->driver.

Move the function nearer its only user and instead of the ?: operator use a
normal "if" which is more readable.

Link: https://lore.kernel.org/r/20211004125935.2300113-6-u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

powerpc/pci: Remove unimplemented prototypes

The corresponding definitions were deleted in commit 3d5134ee8341
("[POWERPC] Rewrite IO allocation & mapping on powerpc64") which
was merged a mere 13 years ago.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200902035138.1762531-1-oohall@gmail.com

powerpc/pci: Delete traverse_pci_dn()

Nothing uses it.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200902035121.1762475-1-oohall@gmail.com

powerpc/eeh: Convert log messages to eeh_edev_* macros

Convert existing messages, where appropriate, to use the eeh_edev_*
logging macros.

The only effect should be minor adjustments to the log messages, apart
from:

- A new message in pseries_eeh_probe() "Probing device" to match the
powernv case.
- The "Probing device" message in pnv_eeh_probe() is now generated
slightly later, which will mean that it is no longer emitted for
devices that aren't probed due to the initial checks.

Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ce505a0a7a4a5b0367f0f40f8b26e7c0a9cf4cb7.1565930772.git.sbobroff@linux.ibm.com

powerpc/eeh: Add bdfn field to eeh_dev

Preparation for removing pci_dn from the powernv EEH code. The only
thing we really use pci_dn for is to get the bdfn of the device for
config space accesses, so adding that information to eeh_dev reduces
the need to carry around the pci_dn.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
[SB: Re-wrapped commit message, fixed whitespace damage.]
Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/e458eb69a1f591d8a120782f23a8506b15d3c654.1565930772.git.sbobroff@linux.ibm.com

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

powerpc/eeh: Improve recovery of passed-through devices

Currently, the EEH recovery process considers passed-through devices
as if they were not EEH-aware, which can cause them to be removed as
part of recovery. Because device removal requires cooperation from
the guest, this may lead to the process stalling or deadlocking.
Also, if devices are removed on the host side, they will be removed
from their IOMMU group, making recovery in the guest impossible.

Therefore, alter the recovery process so that passed-through devices
are not removed but are instead left frozen (and marked isolated)
until the guest performs it's own recovery. If firmware thaws a
passed-through PE because it's parent PE has been thawed (because it
was not passed through), re-freeze it.

Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/eeh: Add include_passed to eeh_pe_state_clear()

Add a parameter to eeh_pe_state_clear() that allows passed-through PEs
to be excluded. Update callers to always pass true so that there is no
change in behaviour.

Also refactor to use direct traversal, to allow the removal of some
boilerplate.

This is to prepare for follow-up work for passed-through devices.

Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/eeh: Cleanup eeh_pe_state_mark()

Currently, eeh_pe_state_mark() marks a PE (and it's children) with a
state and then performs additional processing if that state included
EEH_PE_ISOLATED.

The state parameter is always a constant at the call site, so
rearrange eeh_pe_state_mark() into two functions and just call the
appropriate one at each site.

Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/eeh: Refactor EEH PE reset functions

eeh_pe_reset and eeh_reset_pe are two different functions in the same
file which do mostly the same thing. Not only is this confusing, but
potentially causes disrepancies in functionality, notably eeh_reset_pe
as it does not check return values for failure.

Refactor this into the following:

- eeh_pe_reset(): stays as is, performs a single operation, exported
- eeh_pe_reset_full(): new, full reset process that calls eeh_pe_reset()
- eeh_reset_pe(): removed and replaced by eeh_pe_reset_full()
- eeh_reset_pe_once(): removed

Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/pci: Delay populating pdn

The pdn (struct pci_dn) instances are allocated from memblock or
bootmem when creating PCI controller (hoses) in setup_arch(). PCI
hotplug, which will be supported by proceeding patches, releases
PCI device nodes and their corresponding pdn on unplugging event.
The memory chunks for pdn instances allocated from memblock or
bootmem are hard to reused after being released.

This delays creating pdn by pci_devs_phb_init() from setup_arch()
to core_initcall() so that they are allocated from slab. The memory
consumed by pdn can be released to system without problem during
PCI unplugging time. It indicates that pci_dn is unavailable in
setup_arch() and the the fixup on pdn (like AGP's) can't be carried
out that time. We have to do that in pcibios_root_bridge_prepare()
on maple/pasemi/powermac platforms where/when the pdn is available.
pcibios_root_bridge_prepare is called from subsys_initcall() which
is executed after core_initcall() so the code flow does not change.

At the mean while, the EEH device is created when pdn is populated,
meaning pdn and EEH device have same life cycle. In turn, we needn't
call eeh_dev_init() to create EEH device explicitly.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/pci: Export pci_traverse_device_nodes()

This renames traverse_pci_devices() to pci_traverse_device_nodes().
The function traverses all subordinate device nodes of the specified
one. Also, below cleanup applied to the function. No logical changes
introduced.

* Rename "pre" to "fn".
* Avoid assignment in if condition reported from checkpatch.pl.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/eeh: Disable automatically blocked PCI config

pcibios_set_pcie_reset_state() could be called to complete
reset request when passing through PCI device, flag
EEH_PE_ISOLATED is set before saving the PCI config sapce.
On some Broadcom adapters, EEH_PE_CFG_BLOCKED is automatically
set when the flag EEH_PE_ISOLATED is marked. It caused bogus
data saved from the PCI config space, which will be restored
to the PCI adapter after the reset. Eventually, the hardware
can't work with corrupted data in PCI config space.

The patch fixes the issue with eeh_pe_state_mark_no_cfg(), which
doesn't set EEH_PE_CFG_BLOCKED when seeing EEH_PE_ISOLATED on the
PE, in order to avoid the bogus data saved and restored to the PCI
config space.

Reported-by: Rajanikanth H. Adaveeshaiah <rajanikanth.ha@in.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc: move find_and_init_phbs() to pSeries specific code

Previously, find_and_init_phbs() was used in both PowerNV and pSeries
setup. However, since RTAS support has been dropped from PowerNV, we
can move it into a platform-specific file.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/eeh: Create eeh_dev from pci_dn instead of device_node

The patch adds function traverse_pci_dn(), which is similar to
traverse_pci_devices() except it takes pci_dn, not device_node
as parameter. The pci_dev.c has been reworked to create eeh_dev
from pci_dn, instead of device_node.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc/eeh: No hotplug on permanently removed dev

The issue was detected in a bit complicated test case where
we have multiple hierarchical PEs shown as following figure:

+-----------------+
| PE#3 p2p#0 |
| p2p#1 |
+-----------------+
|
+-----------------+
| PE#4 pdev#0 |
| pdev#1 |
+-----------------+

PE#4 (have 2 PCI devices) is the child of PE#3, which has 2 p2p
bridges. We accidentally had less-known scenario: PE#4 was removed
permanently from the system because of permanent failure (e.g.
exceeding the max allowd failure times in last hour), then we detects
EEH errors on PE#3 and tried to recover it. However, eeh_dev instances
for pdev#0/1 were not detached from PE#4, which was still connected to
PE#3. All of that was because of the fact that we rely on count-based
pcibios_release_device(), which isn't reliable enough. When doing
recovery for PE#3, we still apply hotplug on PE#4 and pdev#0/1, which
are not valid any more. Eventually, we run into kernel crash.

The patch fixes above issue from two aspects. For unplug, we simply
skip those permanently removed PE, whose state is (EEH_PE_STATE_ISOLATED
&& !EEH_PE_STATE_RECOVERING) and its frozen count should be greater
than EEH_MAX_ALLOWED_FREEZES. For plug, we marked all permanently
removed EEH devices with EEH_DEV_REMOVED and return 0xFF's on read
its PCI config so that PCI core will omit them.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc/eeh: Cleanup on EEH PCI address cache

The patch does cleanup on EEH PCI address cache based on the fact
EEH core is the only user of the component.

* Cleanup on function names so that they all have prefix
"eeh" and looks more short.
* Function printk() has been replaced with pr_debug() or
pr_warning() accordingly.

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

powerpc/eeh: Trace eeh device from I/O cache

The idea comes from Benjamin Herrenschmidt. The eeh cache helps
fetching the pci device according to the given I/O address. Since
the eeh cache is serving for eeh, it's reasonable for eeh cache
to trace eeh device except pci device.

The patch make eeh cache to trace eeh device. Also, the major
eeh entry function eeh_dn_check_failure has been renamed to
eeh_dev_check_failure since it will take eeh device as input
parameter.

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

powerpc/eeh: Probe mode support

While EEH module is installed, PCI devices is checked one by one
to see if it supports eeh. On different platforms, the PCI devices
are referred through different ways when the EEH module is loaded.
For example, on pSeries platform, that is done by OF node. However,
we would do that by real PCI devices (struct pci_dev) on PowerNV
platform in future. So we needs some mechanism to differentiate
those cases by classifying them to probe modes, either from OF
nodes or real PCI devices.

The patch implements the support to eeh probe mode. Also, the
EEH on pSeries has set it into EEH_PROBE_MODE_DEVTREE. That means
the probe will be done based on OF nodes on pSeries platform.

In addition, On pSeries platform, it's done by OF nodes. The patch
moves the the probe function from EEH core to platform dependent
backend and some cleanup applied.

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

powerpc/eeh: Do reset based on PE

The patch implements reset based on PE instead of eeh device. Also,
The functions used to retrieve the reset type, either hot or fundamental
reset, have been reworked for a little bit. More specificly, it's
implemented based the the eeh device traverse function.

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

powerpc/eeh: I/O enable and log retrival based on PE

The patch refactors the original implementation in order to enable
I/O and retrieve EEH log based on PE.

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

powerpc/eeh: Device bars restore based on PE

The patch introduces the function to traverse the devices of the
specified PE and its child PEs. Also, the restore on device bars
is implemented based on the traverse function.

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

powerpc/eeh: Trace error based on PE from beginning

There're 2 conditions to trigger EEH error detection: invalid value
returned from reading I/O or config space. On each case, the function
eeh_dn_check_failure will be called to initialize EEH event and put
it into the poll for further processing.

The patch changes the function for a little bit so that the EEH error
will be traced based on PE instead of EEH device any more. Also, the
function eeh_find_device_pe() has been removed since the eeh device
is tracing the PE by struct eeh_dev::pe.

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

powerpc/eeh: Trace EEH state based on PE

Since we've introduced dedicated struct to trace individual PEs,
it's reasonable to trace its state through the dedicated struct
instead of using "eeh_dev" any more.

The patches implements the state tracing based on PE. It's notable
that the PE state will be applied to the specified PE as well as
its child PEs. That complies with the rule that problematic parent
PE will prevent those child PEs from working properly.

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

powerpc/eeh: Replace pci_dn with eeh_dev for EEH core

The original EEH implementation is heavily depending on struct pci_dn.
We have to put EEH related information to pci_dn. Actually, we could
split struct pci_dn so that the EEH sensitive information to form an
individual struct, then EEH looks more independent.

The patch replaces pci_dn with eeh_dev for EEH core.

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

powerpc/eeh: Cleanup function names in EEH aux components

The patch does some cleanup on the function names of EEH
aux components. Currently, only couple of function names from
eeh_cache have been adjusted so that:

* The function name has prefix "eeh_addr_cache".
* Move around pci_addr_cache_build() in the header file
to reflect function call sequence.

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

powerpc/eeh: pseries platform EEH configure bridge

In order to enable particular PCI device, which has been included
in the parent PE. The involved PCI bridges should be enabled explicitly
if there has. On pSeries platform, there're dedicated RTAS calls
to fulfil the purpose.

The patch implements the function of configuring PCI bridges through
the dedicated RTAS calls. Besides, the function has been abstracted
by struct eeh_ops::configure_bridge so that the EEH core components
could support multiple platforms in future.

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

powerpc/eeh: pseries platform EEH error log retrieval

On RTAS compliant pSeries platform, one dedicated RTAS call has
been introduced to retrieve EEH temporary or permanent error log.

The patch implements the function of retriving EEH error log through
RTAS call. Besides, it has been abstracted by struct eeh_ops::get_log
so that EEH core components could support multiple platforms in future.

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

powerpc/eeh: pseries platform EEH wait PE state

On pSeries platform, the PE state might be temporarily unavailable.
In that case, the firmware will return the corresponding wait time.
That means the kernel has to wait for appropriate time in order to
get the PE state.

The patch does the implementation for that. Besides, the function
has been abstracted through struct eeh_ops::wait_state so that EEH core
components could support multiple platforms in future.

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

powerpc/eeh: pseries platform EEH operations

There're 4 EEH operations that are covered by the dedicated RTAS
call <ibm,set-eeh-option>: enable or disable EEH, enable MMIO and
enable DMA. At early stage of system boot, the EEH would be tried
to enable on PCI device related device node. MMIO and DMA for
particular PE should be enabled when doing recovery on EEH errors
so that the PE could function properly again.

The patch implements it and abstract that through struct
eeh_ops::set_eeh. It would be help for EEH to support multiple
platforms in future.

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

powerpc/eeh: Cleanup function names in the EEH core

The EEH has been implemented on pSeries platform. The original
code looks a little bit nasty. The patch does cleanup on the
current EEH implementation so that it looks more clean.

* Try adding prefix "eeh" for functions.
* Some function names have been adjusted so that they looks
shorter and meaningful.

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

powerpc/eeh: Cleanup comments in the EEH core

The EEH has been implemented on pSeries platform. The original
code looks a little bit nasty. The patch does cleanup on the
current EEH implementation so that it looks more clean.

* Duplicated comments have been removed from the corresponding
header files.
* 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 definitions and calls have unified format as "xxx()".
That means the format "xxx ()" has been replaced by "xxx()".
* There're multiple functions implemented for resetting PE. The
position of those functions have been move around so that they
are adjacent to each other to reflect their relationship.

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

powerpc/PCI: replace pci_probe_only with pci_flags

We already use pci_flags, so this just sets pci_flags directly and removes
the intermediate step of figuring out pci_probe_only, then using it to set
pci_flags.

The PCI core provides a pci_flags definition (currently __weak), so drop
the powerpc definitions in favor of that.

CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

powerpc/pseries/eeh: Fix crash when error happens during device probe

EEH may happen during a PCI driver probe. If the driver is trying to
access some register in a loop, the EEH code will try to print the
driver name. But the driver pointer in struct pci_dev is not set until
probe returns successfully.

Use a function to test if the device and the driver pointer is NULL
before accessing the driver's name.

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc/pci: Fix return type of BUID_{HI,LO} macros

BUID_HI and BUID_LO are used to pass data to call_rtas, which expects
ints or u32s. But the macro doesn't cast the return, so the result is
still u64. Use the upper_32_bits and lower_32_bits macros that have been
added to kernel.h.

Found by getting printf format errors trying to debug print the args, no
actual code change for 64 bit kernels where the macros are actually
used.

Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Acked-by: Linas Vepstas <linasvepstas@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc/eeh: Fix a bug when pci structure is null

During a EEH recover, the pci_dev structure can be null, mainly if an
eeh event is detected during cpi config operation. In this case, the
pci_dev will not be known (and will be null) the kernel will crash
with the following message:

Unable to handle kernel paging request for data at address 0x000000a0
Faulting instruction address: 0xc00000000006b8b4
Oops: Kernel access of bad area, sig: 11 [#1]

NIP [c00000000006b8b4] .eeh_event_handler+0x10c/0x1a0
LR [c00000000006b8a8] .eeh_event_handler+0x100/0x1a0
Call Trace:
[c0000003a80dff00] [c00000000006b8a8] .eeh_event_handler+0x100/0x1a0
[c0000003a80dff90] [c000000000031f1c] .kernel_thread+0x54/0x70

The bug occurs because pci_name() tries to access a null pointer.
This patch just guarantee that pci_name() is not called on Null pointers.

Signed-off-by: Breno Leitao <leitao@linux.vnet.ibm.com>
Signed-off-by: Linas Vepstas <linasvepstas@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc/pci: Merge ppc32 and ppc64 versions of phb_scan()

The two versions are doing almost exactly the same thing. No need to
maintain them as separate files. This patch also has the side effect
of making the PCI device tree scanning code available to 32 bit powerpc
machines, but no board ports actually make use of this feature at this
point.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc: Move include files to arch/powerpc/include/asm

from include/asm-powerpc. This is the result of a

mkdir arch/powerpc/include/asm
git mv include/asm-powerpc/* arch/powerpc/include/asm

Followed by a few documentation/comment fixups and a couple of places
where <asm-powepc/...> was being used explicitly. Of the latter only
one was outside the arch code and it is a driver only built for powerpc.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>