The properties indicates that the hardware supports waking up via magic
packet.
Signed-off-by: Xie Xiaobo <X.Xie@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Fix typo introduced by "powerpc: Add TBI PHY node to first MDIO bus"
from Andy Fleming.
It's device_type rather than device-type, which causes the mdio probe to
fail thus making all gianfar ethernet interfaces unusable.
Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
This is here most likely since the FSL bsp. Back in the FSL bsp it was
set to 50Mhz and working. However the driver divided the SoC freq. only
by 2. According to the TRM the platform clock (which the manual refers
in its formula) is the system clock divided by two. So in the end it has
to divide by 4 and this is what the fsl-spi driver in tree is doing.
Since then the flash is not wokring I guess. After chaning the freq from
50Mhz to 40Mhz like others do then I can access the flash.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
It is not at 0xffa00000. According to current u-boot source the NAND
controller is always at 0xff800000 and it is either at CS0 or CS1
depending on NAND or NAND+NOR mode. In 36bit mode it is shifted to
0xfff800000 but it has always an eight there and never an A.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
For the file "arch/powerpc/sysdev/fsl_rmu.c", there will be some compile
errors while using the corenet64_smp_defconfig:
.../fsl_rmu.c:315: error: cast from pointer to integer of different size
.../fsl_rmu.c:320: error: cast to pointer from integer of different size
.../fsl_rmu.c:320: error: cast to pointer from integer of different size
.../fsl_rmu.c:320: error: cast to pointer from integer of different size
.../fsl_rmu.c:330: error: cast to pointer from integer of different size
.../fsl_rmu.c:332: error: cast to pointer from integer of different size
.../fsl_rmu.c:339: error: cast to pointer from integer of different size
.../fsl_rmu.c:340: error: cast to pointer from integer of different size
.../fsl_rmu.c:341: error: cast to pointer from integer of different size
.../fsl_rmu.c:348: error: cast to pointer from integer of different size
.../fsl_rmu.c:348: error: cast to pointer from integer of different size
.../fsl_rmu.c:348: error: cast to pointer from integer of different size
.../fsl_rmu.c:659: error: cast from pointer to integer of different size
.../fsl_rmu.c:659: error: format '%8.8x' expects type 'unsigned int',
but argument 5 has type 'size_t'
.../fsl_rmu.c:985: error: cast from pointer to integer of different size
.../fsl_rmu.c:997: error: cast to pointer from integer of different size
Rewrote the corresponding code with the support of 64bit building.
Signed-off-by: Liu Gang <Gang.Liu@freescale.com>
Signed-off-by: Shaohui Xie <Shaohui.Xie@freescale.com>
Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
For the file "arch/powerpc/sysdev/fsl_rio.c", there will be some relocation
errors while using the corenet64_smp_defconfig:
WARNING: modpost: Found 6 section mismatch(es).
To see full details build your kernel with:
'make CONFIG_DEBUG_SECTION_MISMATCH=y'
GEN .version
CHK include/generated/compile.h
UPD include/generated/compile.h
CC init/version.o
LD init/built-in.o
LD .tmp_vmlinux1
arch/powerpc/sysdev/built-in.o:(__ex_table+0x0):
relocation truncated to fit: R_PPC64_ADDR16 against `.text'+3208
arch/powerpc/sysdev/built-in.o:(__ex_table+0x2):
relocation truncated to fit: R_PPC64_ADDR16 against `.fixup'
arch/powerpc/sysdev/built-in.o:(__ex_table+0x4):
relocation truncated to fit: R_PPC64_ADDR16 against `.text'+3230
arch/powerpc/sysdev/built-in.o:(__ex_table+0x6):
relocation truncated to fit: R_PPC64_ADDR16 against `.fixup'+c
arch/powerpc/sysdev/built-in.o:(__ex_table+0x8):
relocation truncated to fit: R_PPC64_ADDR16 against `.text'+3250
arch/powerpc/sysdev/built-in.o:(__ex_table+0xa):
relocation truncated to fit: R_PPC64_ADDR16 against `.fixup'+18
Rewrote the corresponding code with the support of 64bit building.
Signed-off-by: Liu Gang <Gang.Liu@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
P1025RDB Overview
------------------
1Gbyte DDR3 SDRAM
32 Mbyte NAND flash
16Mbyte NOR flash
16 Mbyte SPI flash
SD connector to interface with the SD memory card
Real-time clock on I2C bus
PCIe:
- x1 PCIe slot
- x1 mini-PCIe slot
10/100/1000 BaseT Ethernet ports:
- eTSEC1, RGMII: one 10/100/1000 port using AtherosTM AR8021
- eTSEC2, SGMII: one 10/100/1000 port using VitesseTM VSC8221
- eTSEC3, RGMII: one 10/100/1000 port using AtherosTM AR8021
USB 2.0 port:
- Two USB2.0 Type A receptacles
- One USB2.0 signal to Mini PCIe slot
Dual RJ45 UART ports:
- DUART interface: supports two UARTs up to 115200 bps for console display
Signed-off-by: Zhicheng Fan <b32736@freescale.com>
Acked-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Add usb controller version info for the following:
MPC8536, P1010, P1020, P1021, P1022, P1023, P2020, P2041,
P3041, P3060, P5020
Signed-off-by: Ramneek Mehresh <ramneek.mehresh@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
P2020RDB-PC Board shares the same design(PCB) as P102x RDB style platforms.
The difference between this platform and the already existing P2020RDB
is mainly with respect to DDR. The P2020RDB-PC has a DDR3 memory.
The P2020RDB-PC also has a CPLD device connected to local bus.
The main differences from the P102x RDB-PC is 64-bit DDR and SYSCLK of
100Mhz.
Signed-off-by: Prabhakar Kushwaha <prabhakar@freescale.com>
Signed-off-by: Poonam Aggrwal <poonam.aggrwal@freescale.com>
Signed-off-by: Tang Yuantian <b29983@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
P1021RDB-PC Overview
-----------------
1Gbyte DDR3 (on board DDR)
16Mbyte NOR flash
32Mbyte eSLC NAND Flash
256 Kbit M24256 I2C EEPROM
128 Mbit SPI Flash memory
Real-time clock on I2C bus
SD/MMC connector to interface with the SD memory card
PCIex
- x1 PCIe slot or x1 PCIe to dual SATA controller
- x1 mini-PCIe slot
USB 2.0
- ULPI PHY interface: SMSC USB3300 USB PHY and Genesys Logic’s GL850A
- Two USB2.0 Type A receptacles
- One USB2.0 signal to Mini PCIe slot
eTSEC1: Connected to RGMII PHY VSC7385
eTSEC2: Connected to SGMII PHY VSC8221
eTSEC3: Connected to SGMII PHY AR8021
DUART interface: supports two UARTs up to 115200 bps for console display
Signed-off-by: Matthew McClintock <msm@freescale.com>
Signed-off-by: Xu Jiucheng <B37781@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
The registers that describe size supported by TLB are different on MMU
v2 as well as we support power of two page sizes. For now we continue
to assume that FSL variable size array supports all page sizes up to the
maximum one reported in TLB1PS.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
The SERIAL_8250_EXTENDED option just enables access to other
less regularly used options, like SERIAL_8250_SHARE_IRQ.
Select it to get rid of this warning when selecting the child
option living underneath it.
warning: (FSL_SOC_BOOKE && SERIAL_8250_RM9K) selects
SERIAL_8250_SHARE_IRQ which has unmet direct dependencies
(HAS_IOMEM && SERIAL_8250_EXTENDED)
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
The current implementation of lazy interrupts handling has some
issues that this tries to address.
We don't do the various workarounds we need to do when re-enabling
interrupts in some cases such as when returning from an interrupt
and thus we may still lose or get delayed decrementer or doorbell
interrupts.
The current scheme also makes it much harder to handle the external
"edge" interrupts provided by some BookE processors when using the
EPR facility (External Proxy) and the Freescale Hypervisor.
Additionally, we tend to keep interrupts hard disabled in a number
of cases, such as decrementer interrupts, external interrupts, or
when a masked decrementer interrupt is pending. This is sub-optimal.
This is an attempt at fixing it all in one go by reworking the way
we do the lazy interrupt disabling from the ground up.
The base idea is to replace the "hard_enabled" field with a
"irq_happened" field in which we store a bit mask of what interrupt
occurred while soft-disabled.
When re-enabling, either via arch_local_irq_restore() or when returning
from an interrupt, we can now decide what to do by testing bits in that
field.
We then implement replaying of the missed interrupts either by
re-using the existing exception frame (in exception exit case) or via
the creation of a new one from an assembly trampoline (in the
arch_local_irq_enable case).
This removes the need to play with the decrementer to try to create
fake interrupts, among others.
In addition, this adds a few refinements:
- We no longer hard disable decrementer interrupts that occur
while soft-disabled. We now simply bump the decrementer back to max
(on BookS) or leave it stopped (on BookE) and continue with hard interrupts
enabled, which means that we'll potentially get better sample quality from
performance monitor interrupts.
- Timer, decrementer and doorbell interrupts now hard-enable
shortly after removing the source of the interrupt, which means
they no longer run entirely hard disabled. Again, this will improve
perf sample quality.
- On Book3E 64-bit, we now make the performance monitor interrupt
act as an NMI like Book3S (the necessary C code for that to work
appear to already be present in the FSL perf code, notably calling
nmi_enter instead of irq_enter). (This also fixes a bug where BookE
perfmon interrupts could clobber r14 ... oops)
- We could make "masked" decrementer interrupts act as NMIs when doing
timer-based perf sampling to improve the sample quality.
Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---
v2:
- Add hard-enable to decrementer, timer and doorbells
- Fix CR clobber in masked irq handling on BookE
- Make embedded perf interrupt act as an NMI
- Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want
to retrigger an interrupt without preventing hard-enable
v3:
- Fix or vs. ori bug on Book3E
- Fix enabling of interrupts for some exceptions on Book3E
v4:
- Fix resend of doorbells on return from interrupt on Book3E
v5:
- Rebased on top of my latest series, which involves some significant
rework of some aspects of the patch.
v6:
- 32-bit compile fix
- more compile fixes with various .config combos
- factor out the asm code to soft-disable interrupts
- remove the C wrapper around preempt_schedule_irq
v7:
- Fix a bug with hard irq state tracking on native power7
With the original EEH implementation, the access to config space of
the corresponding PCI device is done by RTAS sensitive function. That
depends on pci_dn heavily. That would limit EEH extension to other
platforms like powernv because other platforms might have different
ways to access PCI config space.
The patch splits those functions used to access PCI config space
and implement them in platform related EEH component. It would be
helpful to support EEH on multiple platforms simutaneously in future.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
With the original EEH implementation, the EEH global statistics
are maintained by individual global variables. That makes the
code a little hard to maintain.
The patch introduces extra struct eeh_stats for the EEH global
statistics so that it can be maintained in collective fashion.
It's the rework on the corresponding v5 patch. According to
the comments from David Laight, the EEH global statistics have
been changed for a litte bit so that they have fixed-type of
"u64". Also, the format used to print them has been changed to
"%llu" based on David's suggestion. Also, the output format of
EEH global statistics should be kept as intacted according to
Michael's suggestion that there might be tools parsing them.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The pci_dn has been replaced with eeh_dev. In order to comply with
the rule, the EEH platform implementation on pSeries should also
be adjusted for a little bit so that it will depend on eeh_dev instead
of pci_dn.
The patch replaces pci_dn with eeh_dev. The corresponding information
will be retrieved from eeh_dev instead of pci_dn.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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 aux components like
event and driver. Also, the eeh_event struct has been adjusted for
a little bit since eeh_dev has linked the associated FDT (Flat Device
Tree) node and PCI device. It's not necessary for eeh_event struct to
trace FDT node and PCI device. We can just simply to trace eeh_dev in
eeh_event.
The patch also renames function pcid_name() to eeh_pcid_name(), which
should be missed in the previous patch where the EEH aux components
have been cleaned up.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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>
With original EEH implementation, struct pci_dn is used while building
PCI I/O address cache, which helps on searching the corresponding
PCI device according to the given physical I/O address. Besides, pci_dn
is associated with the corresponding PCI device while building its
I/O cache.
The patch replaces struct pci_dn with struct eeh_dev so that EEH address
cache won't depend on struct pci_dn. That will help EEH to become an
independent module in future. Besides, the binding of eeh_dev and PCI
device is done while building PCI device I/O cache.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
With original EEH implementation, all EEH related statistics have
been put into struct pci_dn. We've introduced struct eeh_dev to
replace struct pci_dn in EEH core components, including EEH sysfs
component.
The patch shows EEH statistics from struct eeh_dev instead of struct
pci_dn in EEH sysfs component. Besides, it also fixed the EEH device
retrieval from PCI device, which was introduced by the previous patch
in the series of patch.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Original EEH implementation depends on struct pci_dn heavily. However,
EEH shouldn't depend on that actually because EEH needn't share much
information with other PCI components. That's to say, EEH should have
worked independently.
The patch introduces struct eeh_dev so that EEH core components needn't
be working based on struct pci_dn in future. Also, struct pci_dn, struct
eeh_dev instances are created in dynamic fasion and the binding with EEH
device, OF node, PCI device is implemented as well.
The EEH devices are created after PHBs are detected and initialized, but
PCI emunation hasn't started yet. Apart from that, PHB might be created
dynamically through DLPAR component and the EEH devices should be creatd
as well. Another case might be OF node is created dynamically by DR
(Dynamic Reconfiguration), which has been defined by PAPR. For those OF
nodes created by DR, EEH devices should be also created accordingly. The
binding between EEH device and OF node is done while the EEH device is
initially created.
The binding between EEH device and PCI device should be done after PCI
emunation is done. Besides, PCI hotplug also needs the binding so that
the EEH devices could be traced from the newly coming PCI buses or PCI
devices.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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>
There're several EEH aux components and the patch does some cleanup
for them so that they look more clean.
* Duplicated comments have been removed from the header file.
* Comments have been reorganized so that it looks more clean.
* The leading comments of functions are adjusted for a little
bit so that the result of "make pdfdocs" would be more
unified.
* Function calls "xxx ()" has been replaced by "xxx()".
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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>
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>
On RTAS compliant pSeries platform, there is a dedicated RTAS call
(ibm,set-slot-reset) to reset the specified PE. Furthermore, two
types of resets are supported: hot and fundamental. the type of
reset is to be used actually depends on the included PCI device's
requirements.
The patch implements resetting PE on pSeries platform through RTAS
call. Besides, it has been abstracted through struct eeh_ops::reset
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>
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>
On pSeries platform, there're 2 dedicated RTAS calls introduced to
retrieve the corresponding PE's state: ibm,read-slot-reset-state and
ibm,read-slot-reset-state2.
The patch implements the retrieval of PE's state according to the
given PE address. Besides, the implementation has been abstracted by
struct eeh_ops::get_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>
There're 2 types of addresses used for EEH operations. The first
one would be BDF (Bus/Device/Function) address which is retrieved
from the reg property of the corresponding FDT node. Another one
is PE address that should be enquired from firmware through RTAS
call on pSeries platform. When issuing EEH operation, the PE address
has precedence over BDF address.
The patch implements retrieving PE address according to the given
BDF address on pSeries platform. Also, the struct eeh_early_enable_info
has been removed since the information can be figured out from
dn->pdn->phb->buid directly and that simplifies the code.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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>
The platform specific EEH operations have been abstracted by
struct eeh_ops. The individual platroms, including pSeries, needs
doing necessary initialization before the platform dependent EEH
operations work properly.
The patch is addressing that and do necessary platform initialization
for pSeries platform. More specificly, it will figure out the tokens
of EEH related RTAS calls.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
EEH has been implemented on RTAS-compliant pSeries platform.
That's to say, the EEH operations will be implemented through RTAS
calls eventually. The situation limited feasible extension on EEH.
In order to support EEH on multiple platforms like pseries and powernv
simutaneously. We have to split the platform dependent EEH options
up out of current implementation.
The patch addresses supporting EEH on multiple platforms. The pseries
platform dependent EEH operations will be abstracted by struct eeh_ops.
EEH core components will be built based on the registered EEH operations.
With the mechanism, what the individual platform needs to do is implement
platform dependent EEH operations.
For now, the pseries platform is covered under the mechanism. That means
we have to think about other platforms to support EEH, like powernv.
Besides, we only have framework for the mechanism and we have to implement
it for pseries platform later.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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>
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>
On 64-bit, the mfmsr instruction can be quite slow, slower
than loading a field from the cache-hot PACA, which happens
to already contain the value we want in most cases.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We were using CR0.EQ after EXCEPTION_COMMON, hoping it still
contained whether we came from userspace or kernel space.
However, under some circumstances, EXCEPTION_COMMON will
call C code and clobber non-volatile registers, so we really
need to re-load the previous MSR from the stackframe and
re-test.
While there, invert the condition to make the fast path more
obvious and remove the BUG_OPCODE which was a debugging
leftover and call .ret_from_except as we should.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When running under a hypervisor that supports stolen time accounting,
we may call C code from the macro EXCEPTION_PROLOG_COMMON in the
exception entry path, which clobbers CR0.
However, the FPU and vector traps rely on CR0 indicating whether we
are coming from userspace or kernel to decide what to do.
So we need to restore that value after the C call
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Also use local_paca instead of get_paca() to avoid getting into
the smp_processor_id() debugging code from the debugger
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Other architectures such as x86 and ARM have been growing
new support for features like retrying page faults after
dropping the mm semaphore to break contention, or being
able to return from a stuck page fault when a SIGKILL is
pending.
This refactors our implementation of do_page_fault() to
move the error handling out of line in a way similar to
x86 and adds support for those two features.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
If we get a floating point, altivec or vsx unavaible interrupt in
kernel, we trigger a kernel error. There is no point preserving
the interrupt state, in fact, that can even make debugging harder
as the processor state might change (we may even preempt) between
taking the exception and landing in a debugger.
So just make those 3 disable interrupts unconditionally.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---
v2: On BookE only disable when hitting the kernel unavailable
path, otherwise it will fail to restore softe as
fast_exception_return doesn't do it.
We currently turn interrupts back to their previous state before
calling do_page_fault(). This can be annoying when debugging as
a bad fault will potentially have lost some processor state before
getting into the debugger.
We also end up calling some generic code with interrupts enabled
such as notify_page_fault() with interrupts enabled, which could
be unexpected.
This changes our code to behave more like other architectures,
and make the assembly entry code call into do_page_faults() with
interrupts disabled. They are conditionally re-enabled from
within do_page_fault() in the same spot x86 does it.
While there, add the might_sleep() test in the case of a successful
trylock of the mmap semaphore, again like x86.
Also fix a bug in the existing assembly where r12 (_MSR) could get
clobbered by C calls (the DTL accounting in the exception common
macro and DISABLE_INTS) in some cases.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---
v2. Add the r12 clobber fix
Some exceptions would unconditionally disable interrupts on entry,
which is fine, but calling lockdep every time not only adds more
overhead than strictly needed, but also means we get quite a few
"redudant" disable logged, which makes it hard to spot the really
bad ones.
So instead, split the macro used by the exception code into a
normal one and a separate one used when CONFIG_TRACE_IRQFLAGS is
enabled, and make the later skip th tracing if interrupts were
already disabled.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We unconditionally hard enable interrupts. This is unnecessary as
syscalls are expected to always be called with interrupts enabled.
While at it, we add a WARN_ON if that is not the case and
CONFIG_TRACE_IRQFLAGS is enabled (we don't want to add overhead
to the fast path when this is not set though).
Thus let's remove the enabling (and associated irq tracing) from
the syscall entry path. Also on Book3S, replace a few mfmsr
instructions with loads of PACAMSR from the PACA, which should be
faster & schedule better.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
