linux-toradex.git/arch/powerpc/platforms, branch v3.4.23

powerpc/eeh: Lock module while handling EEH event

2012-12-03T19:47:23+00:00

commit feadf7c0a1a7c08c74bebb4a13b755f8c40e3bbc upstream.

The EEH core is talking with the PCI device driver to determine the
action (purely reset, or PCI device removal). During the period, the
driver might be unloaded and in turn causes kernel crash as follows:

EEH: Detected PCI bus error on PHB#4-PE#10000
EEH: This PCI device has failed 3 times in the last hour
lpfc 0004:01:00.0: 0:2710 PCI channel disable preparing for reset
Unable to handle kernel paging request for data at address 0x00000490
Faulting instruction address: 0xd00000000e682c90
cpu 0x1: Vector: 300 (Data Access) at [c000000fc75ffa20]
    pc: d00000000e682c90: .lpfc_io_error_detected+0x30/0x240 [lpfc]
    lr: d00000000e682c8c: .lpfc_io_error_detected+0x2c/0x240 [lpfc]
    sp: c000000fc75ffca0
   msr: 8000000000009032
   dar: 490
 dsisr: 40000000
  current = 0xc000000fc79b88b0
  paca    = 0xc00000000edb0380	 softe: 0	 irq_happened: 0x00
    pid   = 3386, comm = eehd
enter ? for help
[c000000fc75ffca0] c000000fc75ffd30 (unreliable)
[c000000fc75ffd30] c00000000004fd3c .eeh_report_error+0x7c/0xf0
[c000000fc75ffdc0] c00000000004ee00 .eeh_pe_dev_traverse+0xa0/0x180
[c000000fc75ffe70] c00000000004ffd8 .eeh_handle_event+0x68/0x300
[c000000fc75fff00] c0000000000503a0 .eeh_event_handler+0x130/0x1a0
[c000000fc75fff90] c000000000020138 .kernel_thread+0x54/0x70
1:mon>

The patch increases the reference of the corresponding driver modules
while EEH core does the negotiation with PCI device driver so that the
corresponding driver modules can't be unloaded during the period and
we're safe to refer the callbacks.

Reported-by: Alexey Kardashevskiy 
Signed-off-by: Gavin Shan 
Signed-off-by: Benjamin Herrenschmidt 
[ herton: backported for 3.5, adjusted driver assignments, return 0
  instead of NULL, assume dev is not NULL ]
Signed-off-by: Herton Ronaldo Krzesinski 
Cc: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

powerpc/eeh: Fix crash on converting OF node to edev

2012-10-12T20:38:39+00:00

commit 1e38b7140185e384da216aff66a711df09b5afc9 upstream.

The kernel crash was reported by Alexy. He was testing some feature
with private kernel, in which Alexy added some code in pci_pm_reset()
to read the CSR after writting it. The bug could be reproduced on
Fiber Channel card (Fibre Channel: Emulex Corporation Saturn-X:
LightPulse Fibre Channel Host Adapter (rev 03)) by the following
commands.

	# echo 1 > /sys/devices/pci0004:01/0004:01:00.0/reset
	# rmmod lpfc
	# modprobe lpfc

The history behind the test case is that those additional config
space reading operations in pci_pm_reset() would cause EEH error,
but we didn't detect EEH error until "modprobe lpfc". For the case,
all the PCI devices on PCI bus (0004:01) were removed and added after
PE reset. Then the EEH devices would be figured out again based on
the OF nodes. Unfortunately, there were some child OF nodes under
PCI device (0004:01:00.0), but they didn't have attached PCI_DN since
they're invisible from PCI domain. However, we were still trying to
convert OF node to EEH device without checking on the attached PCI_DN.
Eventually, it caused the kernel crash as follows:

Unable to handle kernel paging request for data at address 0x00000030
Faulting instruction address: 0xc00000000004d888
cpu 0x0: Vector: 300 (Data Access) at [c000000fc797b950]
    pc: c00000000004d888: .eeh_add_device_tree_early+0x78/0x140
    lr: c00000000004d880: .eeh_add_device_tree_early+0x70/0x140
    sp: c000000fc797bbd0
   msr: 8000000000009032
   dar: 30
 dsisr: 40000000
  current = 0xc000000fc78d9f70
  paca    = 0xc00000000edb0000   softe: 0        irq_happened: 0x00
    pid   = 2951, comm = eehd
enter ? for help
[c000000fc797bc50] c00000000004d848 .eeh_add_device_tree_early+0x38/0x140
[c000000fc797bcd0] c00000000004d848 .eeh_add_device_tree_early+0x38/0x140
[c000000fc797bd50] c000000000051b54 .pcibios_add_pci_devices+0x34/0x190
[c000000fc797bde0] c00000000004fb10 .eeh_reset_device+0x100/0x160
[c000000fc797be70] c0000000000502dc .eeh_handle_event+0x19c/0x300
[c000000fc797bf00] c000000000050570 .eeh_event_handler+0x130/0x1a0
[c000000fc797bf90] c000000000020138 .kernel_thread+0x54/0x70

The patch changes of_node_to_eeh_dev() and just returns NULL if the
passed OF node doesn't have attached PCI_DN.

Reported-by: Alexey Kardashevskiy 
Signed-off-by: Gavin Shan 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

powerpc/85xx: p1022ds: fix DIU/LBC switching with NAND enabled

2012-10-02T17:30:37+00:00

commit 896c01cb4bb3cfc2c0ea9873fa7a9f8bd0a7c8d8 upstream.

In order for indirect mode on the PIXIS to work properly, both chip selects
need to be set to GPCM mode, otherwise writes to the chip select base
addresses will not actually post to the local bus -- they'll go to the
NAND controller instead.  Therefore, we need to set BR0 and BR1 to GPCM
mode before switching to indirect mode.

Signed-off-by: Timur Tabi 
Signed-off-by: Kumar Gala 
Signed-off-by: Greg Kroah-Hartman

powerpc/85xx: p1022ds: disable the NAND flash node if video is enabled

2012-10-02T17:30:37+00:00

commit 6269f2584a359766f53005c676daff8aee60cbed upstream.

The Freescale P1022 has a unique pin muxing "feature" where the DIU video
controller's video signals are muxed with 24 of the local bus address signals.
When the DIU is enabled, the bulk of the local bus is disabled, preventing
access to memory-mapped devices like NAND flash and the pixis FPGA.

Therefore, if the DIU is going to be enabled, then memory-mapped devices on
the localbus, like NAND flash, need to be disabled.

This patch is similar to "powerpc/85xx: p1022ds: disable the NOR flash node
if video is enabled", except that it disables the NAND flash node instead.
This PIXIS node needs to remain enabled because it is used by platform code
to switch into indirect mode.

Signed-off-by: Timur Tabi 
Signed-off-by: Kumar Gala 
Signed-off-by: Greg Kroah-Hartman

powerpc/85xx: use the BRx registers to enable indirect mode on the P1022DS

2012-08-09T15:31:27+00:00

commit 6bd825f02966be8ba544047cab313d6032c23819 upstream.

In order to enable the DIU video controller on the P1022DS, the FPGA needs
to be switched to "indirect mode", where the localbus is disabled and
the FPGA is accessed via writes to localbus chip select signals CS0 and CS1.

To obtain the address of CS0 and CS1, the platform driver uses an "indirect
pixis mode" device tree node.  This node assumes that the localbus 'ranges'
property is sorted in chip-select order.  That is, reg value 0 maps to
CS0, reg value 1 maps to CS1, etc.  This is how the 'ranges' property is
supposed to be arranged.

Unfortunately, the 'ranges' property is often mis-arranged, and not just on
the P1022DS.  Linux normally does not care, since it does not program the
localbus.  But the indirect-mode code on the P1022DS does care.

The "proper" fix is to have U-Boot fix the 'ranges' property, but this would
be too cumbersome.  The names and 'reg' properties of all the localbus
devices would also need to be updated, and determining which localbus device
maps to which chip select is board-specific.

Instead, we determine the CS0/CS1 base addresses the same way that U-boot
does -- by reading the BRx registers directly and mapping them to physical
addresses.  This code is simpler and more reliable, and it does not require
a U-boot or device tree change.

Since the indirect pixis device tree node is no longer needed, the node is
deleted from the DTS.

Signed-off-by: Timur Tabi 
Signed-off-by: Kumar Gala 
Signed-off-by: Greg Kroah-Hartman

powerpc/eeh: Check handle_eeh_events() return value

2012-08-09T15:31:27+00:00

commit 10db8d212864cb6741df7d7fafda5ab6661f6f88 upstream.

Function eeh_event_handler() dereferences the pointer returned by
handle_eeh_events() without checking, causing a crash if NULL was
returned, which is expected in some situations.

This patch fixes this bug by checking for the value returned by
handle_eeh_events() before dereferencing it.

Signed-off-by: Kleber Sacilotto de Souza 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

powerpc: More fixes for lazy IRQ vs. idle

2012-07-16T16:03:49+00:00

commit be2cf20a5ad31ebb13562c1c866ecc626fbd721e upstream.

Looks like we still have issues with pSeries and Cell idle code
vs. the lazy irq state. In fact, the reset fixes that went upstream
are exposing the problem more by causing BUG_ON() to trigger (which
this patch turns into a WARN_ON instead).

We need to be careful when using a variant of low power state that
has the side effect of turning interrupts back on, to properly set
all the SW & lazy state to look as if everything is enabled before
we enter the low power state with MSR:EE off as we will return with
MSR:EE on. If not, we have a discrepancy of state which can cause
things to go very wrong later on.

This patch moves the logic into a helper and uses it from the
pseries and cell idle code. The power4/970 idle code already got
things right (in assembly even !) so I'm not touching it. The power7
"bare metal" idle code is subtly different and correct. Remains PA6T
and some hypervisor based Cell platforms which have questionable
code in there, but they are mostly dead platforms so I'll fix them
when I manage to get final answers from the respective maintainers
about how the low power state actually works on them.

Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

powerpc: check_and_cede_processor() never cedes

2012-07-16T16:03:21+00:00

commit 0b17ba7258db83cd02da560884e053b85de371f2 upstream.

Commit f948501b36c6 ("Make hard_irq_disable() actually hard-disable
interrupts") caused check_and_cede_processor to stop working.
->irq_happened will never be zero right after a hard_irq_disable
so the compiler removes the call to cede_processor completely.

The bug was introduced back in the lazy interrupt handling rework
of 3.4 but was hidden until recently because hard_irq_disable did
nothing.

This issue will eventually appear in 3.4 stable since the
hard_irq_disable fix is marked stable, so mark this one for stable
too.

Signed-off-by: Anton Blanchard 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

powerpc/pseries: Fix software invalidate TCE

2012-07-16T16:03:21+00:00

commit bc6dc752f35488160ffac07ae91bed1bddaea32a upstream.

The following added support for powernv but broke pseries/BML:
 1f1616e powerpc/powernv: Add TCE SW invalidation support

TCE_PCI_SW_INVAL was split into FREE and CREATE flags but the tests in
the pseries code were not updated to reflect this.

Signed-off-by: Michael Neuling 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

powerpc/pseries: Rivet CONFIG_EEH for pSeries platform

2012-04-30T00:45:26+00:00

Recently, Ryan Wang tried to compile PPC pSeries platform without
CONFIG_EEH and eventually run into errors. Nishanth Aravamudan
helped to narrow down the root cause. Actually, the pSeries platform
depends on CONFIG_EEH heavily and that won't work properly without
EEH support.

According to Ben's suggestion, the patch make CONFIG_EEH invisible
and keep it as always selected on pSeries platform.

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