Commit Graph

172 Commits

Author SHA1 Message Date
Gavin Shan 0bd785873c powerpc/eeh: Replace device_node with pci_dn in eeh_ops
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: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2015-03-24 13:15:52 +11:00
Gavin Shan ff57b454dd powerpc/eeh: Do probe on pci_dn
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: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2015-03-24 13:15:52 +11:00
Gavin Shan 28158cd1b7 powerpc/eeh: Enhance pcibios_set_pcie_reset_state()
Function pcibios_set_pcie_reset_state() is possibly called by
pci_reset_function(), on which VFIO infrastructure depends to
issue reset. pcibios_set_pcie_reset_state() is issuing reset
on the parent PE of the indicated PCI device. The reset causes
state lost on all PCI devices except the indicated one as the
argument to pcibios_set_pcie_reset_state(). Also, sideband
MMIO access from guest when issuing reset would cause unexpected
EEH error.

For above two issues, the patch applies following enhancements
to pcibios_set_pcie_reset_state():

   * For all PCI devices except the indicated one, save their
     state prior to reset and restore state after that.
   * Explicitly freeze PE prior to reset and unfreeze it after
     that, in order to avoid unexpected EEH error.

Tested-by: Priya M. A <priyama2@in.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2015-03-17 10:31:18 +11:00
Gavin Shan 1b28f170d9 powerpc/eeh: Allow to set maximal frozen times
When PE's frozen count hits maximal allowed frozen times, which is
5 currently, it will be forced to be offline permanently. Once the
PE is removed permanently, rebooting machine is required to bring
the PE back. It's not convienent when testing EEH functionality.

The patch exports the maximal allowed frozen times through debugfs
entry (/sys/kernel/debug/powerpc/eeh_max_freezes).

Requested-by: Ryan Grimm <grimm@linux.vnet.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-01-23 14:02:54 +11:00
Greg Kurz 221195fb80 powerpc: Drop useless warning in eeh_init()
This is what we get in dmesg when booting a pseries guest and
the hypervisor doesn't provide EEH support.

[    0.166655] EEH functionality not supported
[    0.166778] eeh_init: Failed to call platform init function (-22)

Since both powernv_eeh_init() and pseries_eeh_init() already complain when
hitting an error, it is not needed to print more (especially such an
uninformative message).

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-12-02 11:03:45 +11:00
Gavin Shan a450e8f55a powerpc/eeh: Dump PHB diag-data early
On PowerNV platform, PHB diag-data is dumped after stopping device
drivers. In case of recursive EEH errors, the kernel is usually
crashed before dumping PHB diag-data for the second EEH error. It's
hard to locate the root cause of the second EEH error without PHB
diag-data.

The patch adds one more EEH option "eeh=early_log", which helps
dumping PHB diag-data immediately once frozen PE is detected, in
order to get the PHB diag-data for the second EEH error.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-12-02 11:03:26 +11:00
Gavin Shan b1d76a7d57 powerpc/eeh: Recover EEH error on ownership change for BCM5719
In PCI passthrou scenario, we need simulate EEH recovery for Emulex
adapters when their ownership changes, as we did in commit 5cfb20b96
("powerpc/eeh: Emulate EEH recovery for VFIO devices"). Broadcom
BCM5719 adpaters are facing same problem and needs same cure.

Reported-by: Rajeshkumar Subramanian <rajeshkumars@in.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-12-02 11:03:26 +11:00
Gavin Shan 28bf36f92a powerpc/eeh: Set EEH_PE_RESET on PE reset
The patch introduces additional flag EEH_PE_RESET to indicate the
corresponding PE is under reset. In turn, the PE retrieval bakcend
on PowerNV platform can return unfrozen state for the EEH core to
moving forward. Flag EEH_PE_CFG_BLOCKED isn't the correct one for
the purpose.

In PCI passthrou case, the problem is more worse: Guest doesn't
recover 6th EEH error. The PE is left in isolated (frozen) and
config blocked state on Broadcom adapters. We can't retrieve the
PE's state correctly any more, even from the host side via sysfs
/sys/bus/pci/devices/xxx/eeh_pe_state.

Reported-by: Rajeshkumar Subramanian <rajeshkumars@in.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-12-02 11:03:26 +11:00
Gavin Shan b85743ee95 powerpc/eeh: Refactor eeh_reset_pe()
The patch refactors eeh_reset_pe() in order for:

   * Varied return values for different failure cases.
   * Replace pr_err() with pr_warn() and print function name.
   * Coding style cleanup.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-12-02 11:03:26 +11:00
Gavin Shan c59004cc83 powerpc/eeh: Don't collect logs on PE with blocked config space
When the PE's config space is marked as blocked, PCI config read
requests always return 0xFF's. It's pointless to collect logs in
this case.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-10-15 11:27:21 +11:00
Gavin Shan 8a6b3710cc powerpc/eeh: Rename flag EEH_PE_RESET to EEH_PE_CFG_BLOCKED
The flag EEH_PE_RESET indicates blocking config space of the PE
during reset time. We potentially need block PE's config space
other than reset time. So it's reasonable to replace it with
EEH_PE_CFG_BLOCKED to indicate its usage.

There are no substantial code or logic changes in this patch.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-10-15 11:27:18 +11:00
Gavin Shan f2e0be5e76 powerpc/eeh: Dump PCI config space for all child devices
The PEs can be organized as nested. Current implementation doesn't
dump PCI config space for subordinate devices of child PEs. However,
the frozen PE could be caused by those subordinate devices of its
child PEs.

The patch dumps PCI config space for all subordinate devices of the
problematic PE.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-30 17:15:19 +10:00
Gavin Shan 5cfb20b96f powerpc/eeh: Emulate EEH recovery for VFIO devices
When enabling EEH functionality on passed through devices (PE)
with VFIO, the devices in the PE would be removed permanently
from guest side. In that case, the PE remains frozen state.
When returning PE to host, or restarting the guest again, we
had mechanism unfreezing the PE by clearing PESTA/B frozen
bits. However, that's not enough for some adapters, which are
indicated as following "lspci" shows. Those adapters require
hot reset on the parent bus to bring their firmware back to
workable state. Otherwise, those adaptrs won't be operative
and the host (for returning case) or the guest will fail to
load the drivers for those adapters without exception.

0000:01:00.0 Ethernet controller: Emulex Corporation OneConnect \
             10Gb NIC (be3) (rev 02)
0000:01:00.0 0200: 19a2:0710 (rev 02)
0001:03:00.0 Ethernet controller: Emulex Corporation OneConnect \
             NIC (Lancer) (rev 10)
0001:03:00.0 0200: 10df:e220 (rev 10)

The patch adds mechanism to emulate EEH recovery (for hot reset
on parent PCI bus) on 3 gates to fix the issue: open/release one
adapter of the PE, enable EEH functionality on one adapter of the
PE.

Reported-by:  Murilo Fossa Vicentini <muvic@br.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-30 17:15:18 +10:00
Gavin Shan 93e8b36d7b powerpc/eeh: Tag reset state for user owned PE
PE would be owned by userland, which probably request PE reset
done in host side. During the reset, we should drop the PCI
config accesses to the PE with help of flag EEH_PE_RESET.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-30 17:15:17 +10:00
Gavin Shan 9372dddb18 powerpc/eeh: Block PCI config access during reset
Function pcibios_set_pcie_reset_state() can be used to do PCI
reset. PCI config access during the reset usually causes EEH
errors unexpectedly. In order to avoid the EEH error, the patch
blocks PCI config access during reset with the help of flag
EEH_PE_RESET, which is similar to what we did in EEH PE reset
path.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-30 17:15:15 +10:00
Gavin Shan c9dd014397 powerpc/eeh: Use eeh_unfreeze_pe()
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 <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-30 17:15:14 +10:00
Gavin Shan 4eeeff0ebc powerpc/eeh: Unfreeze PE on enabling EEH functionality
When passing through PE to guest, that's possibly in frozen
state. The driver for the pass-through devices on guest side
can't be loaded successfully as reported. We already had one
gate in eeh_dev_open() to clear PE frozen state accordingly,
but that's not enough because the function is only called at
QEMU startup for once.

The patch adds another gate in eeh_pe_set_option() so that the
PE frozen state can be cleared at QEMU restart time.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-30 17:15:14 +10:00
Gavin Shan 4d4f577e4b powerpc/eeh: Fix improper condition in eeh_pci_enable()
The function eeh_pci_enable() is called to apply various requests
to one particular PE: Enabling EEH, Disabling EEH, Enabling IO,
Enabling DMA, Freezing PE. When enabling IO or DMA on one specific
PE, we need check that IO or DMA isn't enabled previously. But
the condition used to do the check isn't completely correct because
one PE would be in DMA frozen state with workable IO path, or vice
versa.

The patch fixes the improper condition.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-30 17:15:13 +10:00
Gavin Shan 404079c87e powerpc/eeh: Clear frozen state on passing device
When passing through device, its PE might have been put into frozen
state. One obvious example would be: the passed PE is forced to be
offline because of hitting maximal allowed EEH errors in userland.
In that case, the frozen state won't be cleared and then the PE is
returned back to host, which might not have chance detecting and
recovering from it.

The patch adds more check when passing through device and clear the
PE frozen state if necessary.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-30 17:15:08 +10:00
Gavin Shan 316233ff87 powerpc/eeh: Reenable PCI devices after reset
The PCI devices that have been passed through are enabled before
reset, we need restore to the enabled state after reset. Otherwise,
MMIO access might be issued to disabled devices after reset and
causes exceptional recursive EEH error.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-30 17:15:07 +10:00
Gavin Shan 0d5ee5205e powerpc/eeh: Freeze PE before PE reset
The patch adds one more option (EEH_OPT_FREEZE_PE) to set_option()
method to proactively freeze PE, which will be issued before resetting
pass-throughed PE to drop MMIO access during reset because it's
always contributing to recursive EEH error.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-30 17:15:07 +10:00
Gavin Shan 3e938052fb powerpc/eeh: Drop unused argument in eeh_check_failure()
eeh_check_failure() is used to check frozen state of the PE which
owns the indicated I/O address. The argument "val" of the function
isn't used. The patch drops it and return the frozen state of the
PE as expected.

Cc: Vishal Mansur <vmansur@linux.vnet.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-30 17:15:05 +10:00
Wei Yang 2a58222f82 powerpc/eeh: Fix kernel crash when passing through VF
When doing vfio passthrough a VF, the kernel will crash with following
message:

[  442.656459] Unable to handle kernel paging request for data at address 0x00000060
[  442.656593] Faulting instruction address: 0xc000000000038b88
[  442.656706] Oops: Kernel access of bad area, sig: 11 [#1]
[  442.656798] SMP NR_CPUS=1024 NUMA PowerNV
[  442.656890] Modules linked in: vfio_pci mlx4_core nf_conntrack_netbios_ns nf_conntrack_broadcast ipt_MASQUERADE ip6t_REJECT xt_conntrack bnep bluetooth rfkill ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw tg3 nfsd be2net nfs_acl ses lockd ptp enclosure pps_core kvm_hv kvm_pr shpchp binfmt_misc kvm sunrpc uinput lpfc scsi_transport_fc ipr scsi_tgt [last unloaded: mlx4_core]
[  442.658152] CPU: 40 PID: 14948 Comm: qemu-system-ppc Not tainted 3.10.42yw-pkvm+ #37
[  442.658219] task: c000000f7e2a9a00 ti: c000000f6dc3c000 task.ti: c000000f6dc3c000
[  442.658287] NIP: c000000000038b88 LR: c0000000004435a8 CTR: c000000000455bc0
[  442.658352] REGS: c000000f6dc3f580 TRAP: 0300   Not tainted  (3.10.42yw-pkvm+)
[  442.658419] MSR: 9000000000009032 <SF,HV,EE,ME,IR,DR,RI>  CR: 28004882  XER: 20000000
[  442.658577] CFAR: c00000000000908c DAR: 0000000000000060 DSISR: 40000000 SOFTE: 1
GPR00: c0000000004435a8 c000000f6dc3f800 c0000000012b1c10 c00000000da24000
GPR04: 0000000000000003 0000000000001004 00000000000015b3 000000000000ffff
GPR08: c00000000127f5d8 0000000000000000 000000000000ffff 0000000000000000
GPR12: c000000000068078 c00000000fdd6800 000001003c320c80 000001003c3607f0
GPR16: 0000000000000001 00000000105480c8 000000001055aaa8 000001003c31ab18
GPR20: 000001003c10fb40 000001003c360ae8 000000001063bcf0 000000001063bdb0
GPR24: 000001003c15ed70 0000000010548f40 c000001fe5514c88 c000001fe5514cb0
GPR28: c00000000da24000 0000000000000000 c00000000da24000 0000000000000003
[  442.659471] NIP [c000000000038b88] .pcibios_set_pcie_reset_state+0x28/0x130
[  442.659530] LR [c0000000004435a8] .pci_set_pcie_reset_state+0x28/0x40
[  442.659585] Call Trace:
[  442.659610] [c000000f6dc3f800] [00000000000719e0] 0x719e0 (unreliable)
[  442.659677] [c000000f6dc3f880] [c0000000004435a8] .pci_set_pcie_reset_state+0x28/0x40
[  442.659757] [c000000f6dc3f900] [c000000000455bf8] .reset_fundamental+0x38/0x80
[  442.659835] [c000000f6dc3f980] [c0000000004562a8] .pci_dev_specific_reset+0xa8/0xf0
[  442.659913] [c000000f6dc3fa00] [c0000000004448c4] .__pci_dev_reset+0x44/0x430
[  442.659980] [c000000f6dc3fab0] [c000000000444d5c] .pci_reset_function+0x7c/0xc0
[  442.660059] [c000000f6dc3fb30] [d00000001c141ab8] .vfio_pci_open+0xe8/0x2b0 [vfio_pci]
[  442.660139] [c000000f6dc3fbd0] [c000000000586c30] .vfio_group_fops_unl_ioctl+0x3a0/0x630
[  442.660219] [c000000f6dc3fc90] [c000000000255fbc] .do_vfs_ioctl+0x4ec/0x7c0
[  442.660286] [c000000f6dc3fd80] [c000000000256364] .SyS_ioctl+0xd4/0xf0
[  442.660354] [c000000f6dc3fe30] [c000000000009e54] syscall_exit+0x0/0x98
[  442.660420] Instruction dump:
[  442.660454] 4bfffce9 4bfffee4 7c0802a6 fbc1fff0 fbe1fff8 f8010010 f821ff81 7c7e1b78
[  442.660566] 7c9f2378 60000000 60000000 e93e02c8 <e8690060> 2fa30000 41de00c4 2b9f0002
[  442.660679] ---[ end trace a64ac9546bcf0328 ]---
[  442.660724]

The reason is current VF is not EEH enabled.

This patch introduces a macro to convert eeh_dev to eeh_pe. By doing so, it
will prevent converting with NULL pointer.

Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com>
Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
CC: Michael Ellerman <mpe@ellerman.id.au>

V3 -> V4:
   1. move the macro definition from include/linux/pci.h to
      arch/powerpc/include/asm/eeh.h

V2 -> V3:
   1. rebased on 3.17-rc4
   2. introduce a macro
   3. use this macro in several other places

V1 -> V2:
   1. code style and patch subject adjustment

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25 23:14:56 +10:00
Gavin Shan 537e5400a0 powerpc/eeh: Export eeh_iommu_group_to_pe()
The function is used by VFIO driver, which might be built as a
dynamic module. So it should be exported.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-07 13:00:02 +10:00
Benjamin Herrenschmidt 2194dc27bd powerpc/eeh: Add missing #ifdef CONFIG_IOMMU_API
Some new functions are exposed for use by the IOMMU code but
won't build when CONFIG_IOMMU_API isn't set, so shield them
appropriately.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05 18:52:59 +10:00
Gavin Shan 0dae27439a powerpc/eeh: Replace pr_warning() with pr_warn()
pr_warn() is equal to pr_warning(), but the former is a bit more
formal according to commit fc62f2f ("kernel.h: add pr_warn for
symmetry to dev_warn, netdev_warn").

The patch replaces pr_warning() with pr_warn().

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05 15:41:34 +10:00
Gavin Shan 0ed352dddb powerpc/eeh: Reduce lines of log dump
The patch prints 4 PCIE or AER config registers each line, which
is part of the EEH log so that it looks a bit more compact.

Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05 15:41:30 +10:00
Gavin Shan dc561fb9e7 powerpc/eeh: Selectively enable IO for error log
According to the experiment I did, PCI config access is blocked
on P7IOC frozen PE by hardware, but PHB3 doesn't do that. That
means we always get 0xFF's while dumping PCI config space of the
frozen PE on P7IOC. We don't have the problem on PHB3. So we have
to enable I/O prioir to collecting error log. Otherwise, meaningless
0xFF's are always returned.

The patch fixes it by EEH flag (EEH_ENABLE_IO_FOR_LOG), which is
selectively set to indicate the case for: P7IOC on PowerNV platform,
pSeries platform.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05 15:41:25 +10:00
Gavin Shan 05b1721d9f powerpc/eeh: Refactor EEH flag accessors
There are multiple global EEH flags. Almost each flag has its own
accessor, which doesn't make sense. The patch refactors EEH flag
accessors so that they look unified:

  eeh_add_flag():   Add EEH flag
  eeh_clear_flag(): Clear EEH flag
  eeh_has_flag():   Check if one specific flag has been set
  eeh_enabled():    Check if EEH functionality has been enabled

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05 15:41:21 +10:00
Gavin Shan a3032ca9f8 powerpc/eeh: Fetch IOMMU table in reliable way
Function eeh_iommu_group_to_pe() iterates each PCI device to check
the binding IOMMU group with get_iommu_table_base(), which possibly
fetches pdev->dev.archdata.dma_data.dma_offset. It's (0x1 << 59)
for "bypass" cases.

The patch fixes the issue by iterating devices hooked to the IOMMU
group and fetch IOMMU table there.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05 15:41:16 +10:00
Gavin Shan 212d16cdca powerpc/eeh: EEH support for VFIO PCI device
The patch exports functions to be used by new VFIO ioctl command,
which will be introduced in subsequent patch, to support EEH
functinality for VFIO PCI devices.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05 15:28:48 +10:00
Gavin Shan 05ec424e38 powerpc/eeh: Avoid event on passed PE
We must not handle EEH error on devices which are passed to somebody
else. Instead, we expect that the frozen device owner detects an EEH
error and recovers from it.

This avoids EEH error handling on passed through devices so the device
owner gets a chance to handle them.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05 15:28:47 +10:00
Gavin Shan 357b2f3dd9 powerpc/eeh: Dump PE location code
As Ben suggested, it's meaningful to dump PE's location code
for site engineers when hitting EEH errors. The patch introduces
function eeh_pe_loc_get() to retireve the location code from
dev-tree so that we can output it when hitting EEH errors.

If primary PE bus is root bus, the PHB's dev-node would be tried
prior to root port's dev-node. Otherwise, the upstream bridge's
dev-node of the primary PE bus will be check for the location code
directly.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-06-11 19:12:23 +10:00
Gavin Shan 1ad7a72c5e powerpc/eeh: Report frozen parent PE prior to child PE
When we have the corner case of frozen parent and child PE at the
same time, we have to handle the frozen parent PE prior to the
child. Without clearning the frozen state on parent PE, the child
PE can't be recovered successfully.

The patch searches the EEH PE hierarchy tree and returns the toppest
frozen PE to be handled. It ensures the frozen parent PE will be
handled prior to child PE.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-06-11 17:04:16 +10:00
Gavin Shan 1e54b9383c powerpc/eeh: Fix build error for celleb
Commit 7f52a526f ("powerpc/eeh: Allow to disable EEH") caused
following build error with "celleb_defconfig" as being catched
by Mikey on linux-next.

arch/powerpc/kernel/eeh.c: In function 'eeh_init_proc':
arch/powerpc/kernel/eeh.c:1173:37: error: 'powerpc_debugfs_root' \
undeclared (first use in this function)
arch/powerpc/kernel/eeh.c:1173:37: note: each undeclared identifier \
is reported only once for each function it appears in

Reported-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-05-20 10:54:04 +10:00
Gavin Shan 26833a5029 powerpc/eeh: Make the delay for PE reset unified
Basically, we have 3 types of resets to fulfil PE reset: fundamental,
hot and PHB reset. For the later 2 cases, we need PCI bus reset hold
and settlement delay as specified by PCI spec. PowerNV and pSeries
platforms are running on top of different firmware and some of the
delays have been covered by underly firmware (PowerNV).

The patch makes the delays unified to be done in backend, instead of
EEH core.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-04-28 17:34:48 +10:00
Gavin Shan 7f52a526f6 powerpc/eeh: Allow to disable EEH
The patch introduces bootarg "eeh=off" to disable EEH functinality.
Also, it creates /sys/kerenl/debug/powerpc/eeh_enable to disable
or enable EEH functionality. By default, we have the functionality
enabled.

For PowerNV platform, we will restore to have the conventional
mechanism of clearing frozen PE during PCI config access if we're
going to disable EEH functionality. Conversely, we will rely on
EEH for error recovery.

The patch also fixes the issue that we missed to cover the case
of disabled EEH functionality in function ioda_eeh_event(). Those
events driven by interrupt should be cleared to avoid endless
reporting.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-04-28 17:34:27 +10:00
Gavin Shan 8a5ad35686 powerpc/eeh: Cleanup EEH subsystem variables
There're 2 EEH subsystem variables: eeh_subsystem_enabled and
eeh_probe_mode. We needn't maintain 2 variables and we can just
have one variable and introduce different flags. The patch also
introduces additional flag EEH_FORCE_DISABLE, which will be used
to disable EEH subsystem via boot parameter ("eeh=off") in future.
Besides, the patch also introduces flag EEH_ENABLED, which is
changed to disable or enable EEH functionality on the fly through
debugfs entry in future.

With the patch applied, the creteria to check the enabled EEH
functionality is changed to:

!EEH_FORCE_DISABLED && EEH_ENABLED : Enabled
                       Other cases : Disabled

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-04-28 17:34:23 +10:00
Gavin Shan 2a18dfc6ee powerpc/eeh: Use cached capability for log dump
When calling into eeh_gather_pci_data() on pSeries platform, we
possiblly don't have pci_dev instance yet, but eeh_dev is always
ready. So we use cached capability from eeh_dev instead of pci_dev
for log dump there. In order to keep things unified, we also cache
PCI capability positions to eeh_dev for PowerNV as well.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-04-28 17:34:19 +10:00
Gavin Shan 2d86c385a1 powerpc/eeh: Cleanup eeh_gather_pci_data()
The patch replaces printk(KERN_WARNING ...) with pr_warn() in the
function eeh_gather_pci_data().

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-04-28 17:34:14 +10:00
Gavin Shan 7895470063 powerpc/eeh: Avoid I/O access during PE reset
We have suffered recrusive frozen PE a lot, which was caused
by IO accesses during the PE reset. Ben came up with the good
idea to keep frozen PE until recovery (BAR restore) gets done.
With that, IO accesses during PE reset are dropped by hardware
and wouldn't incur the recrusive frozen PE any more.

The patch implements the idea. We don't clear the frozen state
until PE reset is done completely. During the period, the EEH
core expects unfrozen state from backend to keep going. So we
have to reuse EEH_PE_RESET flag, which has been set during PE
reset, to return normal state from backend. The side effect is
we have to clear frozen state for towice (PE reset and clear it
explicitly), but that's harmless.

We have some limitations on pHyp. pHyp doesn't allow to enable
IO or DMA for unfrozen PE. So we don't enable them on unfrozen PE
in eeh_pci_enable(). We have to enable IO before grabbing logs on
pHyp. Otherwise, 0xFF's is always returned from PCI config space.
Also, we had wrong return value from eeh_pci_enable() for
EEH_OPT_THAW_DMA case. The patch fixes it too.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-04-28 17:34:10 +10:00
Gavin Shan 7b401850a1 powerpc/eeh: EEH_PE_ISOLATED not reflect HW state
When doing PE reset, EEH_PE_ISOLATED is cleared unconditionally.
However, We should remove that if the PE reset has cleared the
frozen state successfully. Otherwise, the flag should be kept.
The patch fixes the issue.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-04-28 17:33:57 +10:00
Gavin Shan 9e04937560 powerpc/eeh: Remove EEH_PE_PHB_DEAD
The PE state (for eeh_pe instance) EEH_PE_PHB_DEAD is duplicate to
EEH_PE_ISOLATED. Originally, those PHBs (PHB PE) with EEH_PE_PHB_DEAD
would be removed from the system. However, it's safe to replace
that with EEH_PE_ISOLATED.

The patch also clear EEH_PE_RECOVERING after fenced PHB has been handled,
either failure or success. It makes the PHB PE state consistent with:

	PHB functions normally		  NONE
	PHB has been removed		  EEH_PE_ISOLATED
	PHB fenced, recovery in progress  EEH_PE_ISOLATED | RECOVERING

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-04-28 17:33:39 +10:00
Gavin Shan 66f9af83e5 powerpc/eeh: Disable EEH on reboot
We possiblly detect EEH errors during reboot, particularly in kexec
path, but it's impossible for device drivers and EEH core to handle
or recover them properly.

The patch registers one reboot notifier for EEH and disable EEH
subsystem during reboot. That means the EEH errors is going to be
cleared by hardware reset or second kernel during early stage of
PCI probe.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-02-17 11:19:39 +11:00
Gavin Shan 2ec5a0adf6 powerpc/eeh: Cleanup on eeh_subsystem_enabled
The patch cleans up variable eeh_subsystem_enabled so that we needn't
refer the variable directly from external. Instead, we will use
function eeh_enabled() and eeh_set_enable() to operate the variable.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-02-17 11:19:39 +11:00
Gavin Shan f26c7a035b powerpc/eeh: Hotplug improvement
When EEH error comes to one specific PCI device before its driver
is loaded, we will apply hotplug to recover the error. During the
plug time, the PCI device will be probed and its driver is loaded.
Then we wrongly calls to the error handlers if the driver supports
EEH explicitly.

The patch intends to fix by introducing flag EEH_DEV_NO_HANDLER and
set it before we remove the PCI device. In turn, we can avoid wrongly
calls the error handlers of the PCI device after its driver loaded.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-01-15 13:58:29 +11:00
Brian King fb48dc2282 powerpc: Increase EEH recovery timeout for SR-IOV
In order to support concurrent adapter firmware download
to SR-IOV adapters on pSeries, each VF will see an EEH event
where the slot will remain in the unavailable state for
the duration of the adapter firmware update, which can take
as long as 5 minutes. Extend the EEH recovery timeout to
account for this.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Acked-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-05 16:08:20 +11:00
Gavin Shan bf898ec5cb powerpc/eeh: Enable PCI_COMMAND_MASTER for PCI bridges
On PHB3, we will fail to fetch IODA tables without PCI_COMMAND_MASTER
on PCI bridges. According to one experiment I had, the MSIx interrupts
didn't raise from the adapter without the bit applied to all upstream
PCI bridges including root port of the adapter. The patch forces to
have that bit enabled accordingly.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-11-21 10:33:35 +11:00
Linus Torvalds 2f466d33f5 PCI changes for the v3.13 merge window:
Resource management
     - Fix host bridge window coalescing (Alexey Neyman)
     - Pass type, width, and prefetchability for window alignment (Wei Yang)
 
   PCI device hotplug
     - Convert acpiphp, acpiphp_ibm to dynamic debug (Lan Tianyu)
 
   Power management
     - Remove pci_pm_complete() (Liu Chuansheng)
 
   MSI
     - Fail initialization if device is not in PCI_D0 (Yijing Wang)
 
   MPS (Max Payload Size)
     - Use pcie_get_mps() and pcie_set_mps() to simplify code (Yijing Wang)
     - Use pcie_set_readrq() to simplify code (Yijing Wang)
     - Use cached pci_dev->pcie_mpss to simplify code (Yijing Wang)
 
   SR-IOV
     - Enable upstream bridges even for VFs on virtual buses (Bjorn Helgaas)
     - Use pci_is_root_bus() to avoid catching virtual buses (Wei Yang)
 
   Virtualization
     - Add x86 MSI masking ops (Konrad Rzeszutek Wilk)
 
   Freescale i.MX6
     - Support i.MX6 PCIe controller (Sean Cross)
     - Increase link startup timeout (Marek Vasut)
     - Probe PCIe in fs_initcall() (Marek Vasut)
     - Fix imprecise abort handler (Tim Harvey)
     - Remove redundant of_match_ptr (Sachin Kamat)
 
   Renesas R-Car
     - Support Gen2 internal PCIe controller (Valentine Barshak)
 
   Samsung Exynos
     - Add MSI support (Jingoo Han)
     - Turn off power when link fails (Jingoo Han)
     - Add Jingoo Han as maintainer (Jingoo Han)
     - Add clk_disable_unprepare() on error path (Wei Yongjun)
     - Remove redundant of_match_ptr (Sachin Kamat)
 
   Synopsys DesignWare
     - Add irq_create_mapping() (Pratyush Anand)
     - Add header guards (Seungwon Jeon)
 
   Miscellaneous
     - Enable native PCIe services by default on non-ACPI (Andrew Murray)
     - Cleanup _OSC usage and messages (Bjorn Helgaas)
     - Remove pcibios_last_bus boot option on non-x86 (Bjorn Helgaas)
     - Convert bus code to use bus_, drv_, and dev_groups (Greg Kroah-Hartman)
     - Remove unused pci_mem_start (Myron Stowe)
     - Make sysfs functions static (Sachin Kamat)
     - Warn on invalid return from driver probe (Stephen M. Cameron)
     - Remove Intel Haswell D3 delays (Todd E Brandt)
     - Call pci_set_master() in core if driver doesn't do it (Yinghai Lu)
     - Use pci_is_pcie() to simplify code (Yijing Wang)
     - Use PCIe capability accessors to simplify code (Yijing Wang)
     - Use cached pci_dev->pcie_cap to simplify code (Yijing Wang)
     - Removed unused "is_pcie" from struct pci_dev (Yijing Wang)
     - Simplify sysfs CPU affinity implementation (Yijing Wang))
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.11 (GNU/Linux)
 
 iQIcBAABAgAGBQJSgUzsAAoJEFmIoMA60/r8wmsQAJhwmtkUYR2L4T1g9smAyjJz
 bLm5zoC6WdywFcbTpTBfsTrS1CHIQG5akRgkEXGdr99epiho5F2lwmagWsUR4ijL
 39Qn3knAUMgtNjoVXXI106h/DfTyxSmkZBfih2AQFyWobJq+0kg7hjQQA3+836b4
 8ssWr1+NSl6JJTqYQ0Paw1kSqvvYoXsu5rWFEfCHk8D0s/1bvr5ldAUpk2jTg93I
 uo9/5+O264yt1YoKZOMqAMZLUfd5DaWY1mV3yeF0Uauy1pBmol5csE8ckqJPDrES
 PRdJT1+PhBeLYWcgXANOBZsW58ddxA0pQ5jQV6VJHQWsm5cE82OBpYJf6xUZ2moV
 o6DZ0KRnCPVA3NllYYR16H+wbMfADwwO83QoA+QTIZJy/WgpDH3Cst+m8KePGqbL
 uFgDdXSws9Bs1BCFs7bfYzAM3OdkBFnn+ac7JoPXKP5ibgAp9nDlurgK2r90zRnp
 j15vHMx0mV+e8B8/iwiW5eRtg7NoCHYiNfFy7JalOlsPmYr2KFazBVKclp13Hng7
 fe/Jy6X4UhWoQPdqsy4ftvSQb0gm1MClxFJeZ3VAt6LY9j8OP6S/Vdf6lpAL85KR
 lAQoQzB+lOhTPdXxFY2xgGkITkqPDOQMjPfowYUYFwybqBuG6BHXZPJobL+niBlb
 Nh+M2WlUUA9Z3V6rWJB6
 =CTPk
 -----END PGP SIGNATURE-----

Merge tag 'pci-v3.13-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI changes from Bjorn Helgaas:
 "Resource management
    - Fix host bridge window coalescing (Alexey Neyman)
    - Pass type, width, and prefetchability for window alignment (Wei Yang)

  PCI device hotplug
    - Convert acpiphp, acpiphp_ibm to dynamic debug (Lan Tianyu)

  Power management
    - Remove pci_pm_complete() (Liu Chuansheng)

  MSI
    - Fail initialization if device is not in PCI_D0 (Yijing Wang)

  MPS (Max Payload Size)
    - Use pcie_get_mps() and pcie_set_mps() to simplify code (Yijing Wang)
    - Use pcie_set_readrq() to simplify code (Yijing Wang)
    - Use cached pci_dev->pcie_mpss to simplify code (Yijing Wang)

  SR-IOV
    - Enable upstream bridges even for VFs on virtual buses (Bjorn Helgaas)
    - Use pci_is_root_bus() to avoid catching virtual buses (Wei Yang)

  Virtualization
    - Add x86 MSI masking ops (Konrad Rzeszutek Wilk)

  Freescale i.MX6
    - Support i.MX6 PCIe controller (Sean Cross)
    - Increase link startup timeout (Marek Vasut)
    - Probe PCIe in fs_initcall() (Marek Vasut)
    - Fix imprecise abort handler (Tim Harvey)
    - Remove redundant of_match_ptr (Sachin Kamat)

  Renesas R-Car
    - Support Gen2 internal PCIe controller (Valentine Barshak)

  Samsung Exynos
    - Add MSI support (Jingoo Han)
    - Turn off power when link fails (Jingoo Han)
    - Add Jingoo Han as maintainer (Jingoo Han)
    - Add clk_disable_unprepare() on error path (Wei Yongjun)
    - Remove redundant of_match_ptr (Sachin Kamat)

  Synopsys DesignWare
    - Add irq_create_mapping() (Pratyush Anand)
    - Add header guards (Seungwon Jeon)

  Miscellaneous
    - Enable native PCIe services by default on non-ACPI (Andrew Murray)
    - Cleanup _OSC usage and messages (Bjorn Helgaas)
    - Remove pcibios_last_bus boot option on non-x86 (Bjorn Helgaas)
    - Convert bus code to use bus_, drv_, and dev_groups (Greg Kroah-Hartman)
    - Remove unused pci_mem_start (Myron Stowe)
    - Make sysfs functions static (Sachin Kamat)
    - Warn on invalid return from driver probe (Stephen M. Cameron)
    - Remove Intel Haswell D3 delays (Todd E Brandt)
    - Call pci_set_master() in core if driver doesn't do it (Yinghai Lu)
    - Use pci_is_pcie() to simplify code (Yijing Wang)
    - Use PCIe capability accessors to simplify code (Yijing Wang)
    - Use cached pci_dev->pcie_cap to simplify code (Yijing Wang)
    - Removed unused "is_pcie" from struct pci_dev (Yijing Wang)
    - Simplify sysfs CPU affinity implementation (Yijing Wang)"

* tag 'pci-v3.13-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (79 commits)
  PCI: Enable upstream bridges even for VFs on virtual buses
  PCI: Add pci_upstream_bridge()
  PCI: Add x86_msi.msi_mask_irq() and msix_mask_irq()
  PCI: Warn on driver probe return value greater than zero
  PCI: Drop warning about drivers that don't use pci_set_master()
  PCI: Workaround missing pci_set_master in pci drivers
  powerpc/pci: Use pci_is_pcie() to simplify code [fix]
  PCI: Update pcie_ports 'auto' behavior for non-ACPI platforms
  PCI: imx6: Probe the PCIe in fs_initcall()
  PCI: Add R-Car Gen2 internal PCI support
  PCI: imx6: Remove redundant of_match_ptr
  PCI: Report pci_pme_active() kmalloc failure
  mn10300/PCI: Remove useless pcibios_last_bus
  frv/PCI: Remove pcibios_last_bus
  PCI: imx6: Increase link startup timeout
  PCI: exynos: Remove redundant of_match_ptr
  PCI: imx6: Fix imprecise abort handler
  PCI: Fail MSI/MSI-X initialization if device is not in PCI_D0
  PCI: imx6: Remove redundant dev_err() in imx6_pcie_probe()
  x86/PCI: Coalesce multiple overlapping host bridge windows
  ...
2013-11-14 14:02:00 +09:00
Yijing Wang 9437eca181 powerpc/pci: Use pci_is_pcie() to simplify code [fix]
Fix f0308261b1 ("powerpc/pci: Use pci_is_pcie() to simplify code").  I
accidentally merged v2 instead of v3, so this adds the difference.  Without
this, "cap" is the left-over PCI-X capability offset, and we're using it as
the PCIe capability offset.

[bhelgaas: extracted v2->v3 diff]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-11-04 16:51:31 -07:00
Gavin Shan 5293bf97a2 powerpc/eeh: Reorder output messages
We already had some output messages from EEH core. Occasionally,
we can see the output messages from EEH core before the stack
dump. That's not what we expected. The patch fixes that and shows
the stack dump prior to output messages from EEH core.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-11 16:54:15 +11:00
Yijing Wang f0308261b1 powerpc/pci: Use pci_is_pcie() to simplify code
Use pci_is_pcie() to simplify code.

Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Reviewed-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Cc: Gavin Shan <shangw@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
2013-09-23 17:30:04 -06:00
Mike Qiu 144136dd7a powerpc/eeh: Add missing procfs entry for PowerNV
The procfs entry for global statistics has been missed on PowerNV
platform and the patch is going to add that.

Signed-off-by: Mike Qiu <qiudayu@linux.vnet.ibm.com>
Acked-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-08-09 18:06:47 +10:00
Gavin Shan ab55d2187d powerpc/eeh: Introdce flag to protect sysfs
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 <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-24 14:18:49 +10:00
Gavin Shan f5c57710dd powerpc/eeh: Use partial hotplug for EEH unaware drivers
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 <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-24 14:18:48 +10:00
Gavin Shan 9feed42e93 powerpc/eeh: Use safe list traversal when walking EEH devices
Currently, we're trasversing the EEH devices list using list_for_each_entry().
That's not safe enough because the EEH devices might be removed from
its parent PE while doing iteration. The patch replaces that with
list_for_each_entry_safe().

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-24 14:18:47 +10:00
Gavin Shan 807a827d4e powerpc/eeh: Keep PE during hotplug
When we do normal hotplug, the PE (shadow EEH structure) shouldn't be
kept around.

However, we need to keep it if the hotplug an artifial one caused by
EEH errors recovery.

Since we remove EEH device through the PCI hook pcibios_release_device(),
the flag "purge_pe" passed to various functions is meaningless. So the patch
removes the meaningless flag and introduce new flag "EEH_PE_KEEP"
to save the PE while doing hotplug during EEH error recovery.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-24 14:18:47 +10:00
Gavin Shan f2856491d2 powerpc/eeh: Export functions for hotplug
Make some functions public in order to support hotplug on either specific
PCI bus or PCI device in future.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-24 14:18:46 +10:00
Gavin Shan 0ba178888b powerpc/eeh: Remove reference to PCI device
We will rely on pcibios_release_device() to remove the EEH cache
and unbind EEH device for the specific PCI device. So we shouldn't
hold the reference to the PCI device from EEH cache and EEH device.
Otherwise, pcibios_release_device() won't be called as we expected.
The patch removes the reference to the PCI device in EEH core.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-24 14:18:46 +10:00
Gavin Shan eeb6361fdd powerpc/eeh: Avoid build warnings
The patch is for avoiding following build warnings:

   The function .pnv_pci_ioda_fixup() references
   the function __init .eeh_init().
   This is often because .pnv_pci_ioda_fixup lacks a __init

   The function .pnv_pci_ioda_fixup() references
   the function __init .eeh_addr_cache_build().
   This is often because .pnv_pci_ioda_fixup lacks a __init

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-01 11:10:33 +10:00
Gavin Shan 56ca4fde90 powerpc/eeh: Refactor the output message
We needn't the the whole backtrace other than one-line message in
the error reporting interrupt handler. For errors triggered by
access PCI config space or MMIO, we replace "WARN(1, ...)" with
pr_err() and dump_stack(). The patch also adds more output messages
to indicate what EEH core is doing. Besides, some printk() are
replaced with pr_warning().

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-01 11:10:33 +10:00
Gavin Shan c35ae1796b powerpc/eeh: Don't collect PCI-CFG data on PHB
When the PHB is fenced or dead, it's pointless to collect the data
from PCI config space of subordinate PCI devices since it should
return 0xFF's. The patch also fixes overwritten buffer while getting
PCI config data.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-01 11:10:31 +10:00
Gavin Shan ef6a285773 powerpc/eeh: Remove eeh_mutex
Originally, eeh_mutex was introduced to protect the PE hierarchy
tree and the attached EEH devices because EEH core was possiblly
running with multiple threads to access the PE hierarchy tree.
However, we now have only one kthread in EEH core. So we needn't
the eeh_mutex and just remove it.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-25 17:24:41 +10:00
Aneesh Kumar K.V 12bc9f6fc1 powerpc: Replace find_linux_pte with find_linux_pte_or_hugepte
Replace find_linux_pte with find_linux_pte_or_hugepte and explicitly
document why we don't need to handle transparent hugepages at callsites.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-21 16:01:54 +10:00
Gavin Shan b95cd2cd44 powerpc/eeh: Allow to check fenced PHB proactively
It's meaningless to handle frozen PE if we already had fenced PHB.
The patch intends to check the PHB state before checking PE. If the
PHB has been put into fenced state, we need take care of that firstly.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20 17:06:53 +10:00
Gavin Shan 4907581dc2 powerpc/eeh: Export confirm_error_lock
An EEH event is created and queued to the event queue for each
ingress EEH error. When there're mutiple EEH errors, we need serialize
the process to keep consistent PE state (flags). The spinlock
"confirm_error_lock" was introduced for the purpose. We'll inject
EEH event upon error reporting interrupts on PowerNV platform. So
we export the spinlock for that to use for consistent PE state.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20 17:06:11 +10:00
Gavin Shan c86085580d powerpc/eeh: Single kthread to handle events
We possiblly have multiple kthreads running for multiple EEH errors
(events) and use one spinlock to make the process of handling those
EEH events serialized. That's unnecessary and the patch creates only
one kthread, which is started during EEH core initialization time in
eeh_init(). A new semaphore introduced to count the number of existing
EEH events in the queue and the kthread waiting on the semaphore.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20 17:06:01 +10:00
Gavin Shan 26a74850b3 powerpc/eeh: Delay EEH probe during hotplug
While doing EEH recovery, the PCI devices of the problematic PE
should be removed and then added to the system again. During the
so-called hotplug event, the PCI devices of the problematic PE
will be probed through early/late phase. We would delay EEH probe
on late point for PowerNV platform since the PCI device isn't
available in early phase.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20 17:05:58 +10:00
Gavin Shan 326a98ea93 powerpc/eeh: Refactor eeh_reset_pe_once()
We shouldn't check that the returned PE status is exactly equal to
(EEH_STATE_MMIO_ACTIVE | EEH_STATE_DMA_ACTIVE) but instead only check
that they are both set.

[benh: changelog]
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20 17:05:54 +10:00
Gavin Shan 21fd21f590 powerpc/eeh: EEH post initialization operation
The patch adds new EEH operation post_init. It's used to notify
the platform that EEH core has completed the EEH probe. By that,
PowerNV platform starts to use the services supplied by EEH
functionality.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20 17:05:51 +10:00
Gavin Shan 51fb5f5632 powerpc/eeh: Make eeh_init() public
For EEH on PowerNV platform, we will do EEH probe based on the
real PCI devices. The PCI devices are available after PCI probe.
So we have to call eeh_init() explicitly on PowerNV platform
after PCI probe. The patch also does EEH probe for PowerNV platform
in eeh_init().

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20 17:05:48 +10:00
Gavin Shan 317f06de78 powerpc/eeh: Move common part to kernel directory
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: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20 17:05:35 +10:00