If we set irq_work on a processor and immediately afterward, before the
irq work has a chance to be processed, we change the decrementer value,
we can seriously delay the handling of that irq_work.
Fix it by checking in a few places for pending irq work, first before
changing the decrementer in decrementer_set_next_event() and after
changing it in the same function and in timer_interrupt().
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Huge Dickins reported an issue that b5ff4211a8
"powerpc/book3s: Queue up and process delayed MCE events" breaks the
PowerMac G5 boot. This patch fixes it by moving the mce even processing
away from syscall exit, which was wrong to do that in first place, and
using irq work framework to delay processing of mce event.
Reported-by: Hugh Dickins <hughd@google.com
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Commit fbd7740fdfdf9475f(powerpc: Simplify pSeries idle loop) switched pseries cpu
idle handling from complete idle loops to ppc_md.powersave functions. Earlier to
this switch, ppc64_runlatch_off() had to be called in each of the idle routines.
But after the switch, this call is handled in arch_cpu_idle(),just before the call
to ppc_md.powersave, where platform specific idle routines are called.
As a consequence, the call to ppc64_runlatch_off() got duplicated in the
arch_cpu_idle() routine as well as in the some of the idle routines in
pseries and commit fbd7740fdf missed to get rid of these redundant
calls. These calls were carried over subsequent enhancements to the pseries
cpuidle routines.
Although multiple calls to ppc64_runlatch_off() is harmless, there is still some
overhead due to it. Besides that, these calls could also make way for a
misunderstanding that it is *necessary* to call ppc64_runlatch_off() multiple
times, when that is not the case. Hence this patch takes care of eliminating
this redundancy.
Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
add_system_ram_resources() is a subsys_initcall.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This makes ppc64_defconfig bootable without initrd on pasemi systems,
most of whom have MV SATA controllers. Some have SIL24, but that driver
is already enabled.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
At present we assume candidate image is <= 256MB. But in P8,
candidate image size can go up to 750MB. Hence increasing
candidate image max size to 1GB.
Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
There have been some weird bugs in the past where the kernel tried to associate
threads of the same core to different NUMA nodes, and things went haywire after
that point (as expected).
But unfortunately, root-causing such issues have been quite challenging, due to
the lack of appropriate debug checks in the kernel. These bugs usually lead to
some odd soft-lockups in the scheduler's build-sched-domain code in the CPU
hotplug path, which makes it very hard to trace it back to the incorrect
cpu-to-node mappings.
So add appropriate debug checks to catch such invalid cpu-to-node mappings
as early as possible.
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
On POWER platforms, the hypervisor can notify the guest kernel about dynamic
changes in the cpu-numa associativity (VPHN topology update). Hence the
cpu-to-node mappings that we got from the firmware during boot, may no longer
be valid after such updates. This is handled using the arch_update_cpu_topology()
hook in the scheduler, and the sched-domains are rebuilt according to the new
mappings.
But unfortunately, at the moment, CPU hotplug ignores these updated mappings
and instead queries the firmware for the cpu-to-numa relationships and uses
them during CPU online. So the kernel can end up assigning wrong NUMA nodes
to CPUs during subsequent CPU hotplug online operations (after booting).
Further, a particularly problematic scenario can result from this bug:
On POWER platforms, the SMT mode can be switched between 1, 2, 4 (and even 8)
threads per core. The switch to Single-Threaded (ST) mode is performed by
offlining all except the first CPU thread in each core. Switching back to
SMT mode involves onlining those other threads back, in each core.
Now consider this scenario:
1. During boot, the kernel gets the cpu-to-node mappings from the firmware
and assigns the CPUs to NUMA nodes appropriately, during CPU online.
2. Later on, the hypervisor updates the cpu-to-node mappings dynamically and
communicates this update to the kernel. The kernel in turn updates its
cpu-to-node associations and rebuilds its sched domains. Everything is
fine so far.
3. Now, the user switches the machine from SMT to ST mode (say, by running
ppc64_cpu --smt=1). This involves offlining all except 1 thread in each
core.
4. The user then tries to switch back from ST to SMT mode (say, by running
ppc64_cpu --smt=4), and this involves onlining those threads back. Since
CPU hotplug ignores the new mappings, it queries the firmware and tries to
associate the newly onlined sibling threads to the old NUMA nodes. This
results in sibling threads within the same core getting associated with
different NUMA nodes, which is incorrect.
The scheduler's build-sched-domains code gets thoroughly confused with this
and enters an infinite loop and causes soft-lockups, as explained in detail
in commit 3be7db6ab (powerpc: VPHN topology change updates all siblings).
So to fix this, use the numa_cpu_lookup_table to remember the updated
cpu-to-node mappings, and use them during CPU hotplug online operations.
Further, we also need to ensure that all threads in a core are assigned to a
common NUMA node, irrespective of whether all those threads were online during
the topology update. To achieve this, we take care not to use cpu_sibling_mask()
since it is not hotplug invariant. Instead, we use cpu_first_sibling_thread()
and set up the mappings manually using the 'threads_per_core' value for that
particular platform. This helps us ensure that we don't hit this bug with any
combination of CPU hotplug and SMT mode switching.
Cc: stable@vger.kernel.org
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Some devices, for example PCI root port, don't have IOMMU table and
group. We needn't detach them from their IOMMU group. Otherwise, it
potentially incurs kernel crash because of referring NULL IOMMU group
as following backtrace indicates:
.iommu_group_remove_device+0x74/0x1b0
.iommu_bus_notifier+0x94/0xb4
.notifier_call_chain+0x78/0xe8
.__blocking_notifier_call_chain+0x7c/0xbc
.blocking_notifier_call_chain+0x38/0x48
.device_del+0x50/0x234
.pci_remove_bus_device+0x88/0x138
.pci_stop_and_remove_bus_device+0x2c/0x40
.pcibios_remove_pci_devices+0xcc/0xfc
.pcibios_remove_pci_devices+0x3c/0xfc
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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>
The patch implements the EEH operation backend restore_config()
for PowerNV platform. That relies on OPAL API opal_pci_reinit()
where we reinitialize the error reporting properly after PE or
PHB reset.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
After reset on the specific PE or PHB, we never configure AER
correctly on PowerNV platform. We needn't care it on pSeries
platform. The patch introduces additional EEH operation eeh_ops::
restore_config() so that we have chance to configure AER correctly
for PowerNV platform.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We don't have IO ports on PHB3 and the assignment of variable
"iomap_off" on PHB3 is meaningless. The patch just removes the
unnecessary assignment to the variable. The code change should
have been part of commit c35d2a8c ("powerpc/powernv: Needn't IO
segment map for PHB3").
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
After reverting 25ebc45b93
("powerpc/pseries/iommu: remove default window before attempting DDW
manipulation"), we no longer remove the base window in enable_ddw.
Therefore, we no longer need to reset the DMA window state in
find_existing_ddw_windows(). We can instead go back to what was done
before, which simply reuses the previous configuration, if any. Further,
this removes the final caller of the reset-pe-dma-windows call, so
remove those functions.
This fixes an EEH on kdump with the ipr driver. The EEH occurs, because
the initcall removes the DDW configuration (64-bit DMA window), but
doesn't ensure the ops are via the IOMMU -- a DMA operation occurs
during probe (still investigating this) and we EEH.
This reverts commit 14b6f00f8a.
Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Ben rightfully pointed out that there is a race in the "newer" DDW code.
Presuming we are running on recent enough firmware that supports the
"reset" DDW manipulation call, we currently always remove the base
32-bit DMA window in order to maximize the resources for Phyp when
creating the 64-bit window. However, this can be problematic for the
case where multiple functions are in the same PE (partitionable
endpoint), where some funtions might be 32-bit DMA only. All of a
sudden, the only functional DMA window for such functions is gone. We
will have serious errors in such situations. The best solution is simply
to revert the extension to the DDW code where we ever remove the base
DMA window.
This reverts commit 25ebc45b93.
Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>. Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.
The one instance where we add an include for init.h covers off
a case where that file was implicitly getting it from another
header which itself didn't need it.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
GCC 4.8 now generates out-of-line vr save/restore functions when
optimizing for size. They are needed for the raid6 altivec support.
Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Merge tag 'v3.13-rc8' into core/locking
Refresh the tree with the latest fixes, before applying new changes.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull powerpc fix from Ben Herrenschmidt:
"Here's one regression fix for 3.13 that I would appreciate if you
could still pull in. It was an "interesting" one to debug, basically
it's an old bug that got somewhat "exposed" by new code breaking the
boot on PA Semi boards (yes, it does appear that some people are still
using these!)"
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc: Check return value of instance-to-package OF call
On PA-Semi firmware, the instance-to-package callback doesn't seem
to be implemented. We didn't check for error, however, thus
subsequently passed the -1 value returned into stdout_node to
thins like prom_getprop etc...
Thus caused the firmware to load values around 0 (physical) internally
as node structures. It somewhat "worked" as long as we had a NULL in the
right place (address 8) at the beginning of the kernel, we didn't "see"
the bug. But commit 5c0484e25e
"powerpc: Endian safe trampoline" changed the kernel entry point causing
that old bug to now cause a crash early during boot.
This fixes booting on PA-Semi board by properly checking the return
value from instance-to-package.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: Olof Johansson <olof@lixom.net>
---
improve the common clock support code for MPC512x
- expand the CCM register set declaration with MPC5125 related registers
(which reside in the previously "reserved" area)
- tell the MPC5121, MPC5123, and MPC5125 SoC variants apart, and derive
the availability of components and their clocks from the detected SoC
(MBX, AXE, VIU, SPDIF, PATA, SATA, PCI, second FEC, second SDHC,
number of PSC components, type of NAND flash controller,
interpretation of the CPMF bitfield, PSC/CAN mux0 stage input clocks,
output clocks on SoC pins)
- add backwards compatibility (allow operation against a device tree
which lacks clock related specs) for MPC5125 FECs, too
telling SoC variants apart and adjusting the clock tree's generation
occurs at runtime, a common generic binary supports all of the chips
the MPC5125 approach to the NFC clock (one register with two counters
for the high and low periods of the clock) is not implemented, as there
are no users and there is no common implementation which supports this
kind of clock -- the new implementation would be unused and could not
get verified, so it shall wait until there is demand
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
the SDHC clock is derived from CSB with a fractional divider which can
address "quarters"; the implementation multiplies CSB by 4 and divides
it by the (integer) divider value
a bug in the clock domain synchronisation requires that only even
divider values get setup; we achieve this by
- multiplying CSB by 2 only instead of 4
- registering with CCF the divider's bit field without bit0
- the divider's lowest bit remains clear as this is the reset value
and later operations won't touch it
this change keeps fully utilizing common clock primitives (needs no
additional support logic, and avoids an excessive divider table) and
satisfies the hardware's constraint of only supporting even divider
values
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
adjust (expand on or move) a few comments,
add markers for easier navigation around helpers
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
this change removes workarounds which have become obsolete after
migration to common clock support has completed
- remove clkdev registration calls (compatibility clock item aliases)
after all peripheral drivers were adjusted for device tree based
clock lookup
- remove pre-enable workarounds after all peripheral drivers were
adjusted to acquire their respective clock items
workarounds for these clock items get removed: FEC (ethernet), I2C,
PSC (UART, SPI), PSC FIFO, USB, NFC (NAND flash), VIU (video capture),
BDLC (CAN), CAN MCLK, DIU (video output)
these clkdev registered names won't be provided any longer by the
MPC512x platform's clock driver: "psc%d_mclk", "mscan%d_mclk",
"usb%d_clk", "nfc_clk", "viu_clk", "sys_clk", "ref_clk"
the pre-enable workaround for PCI remains, but depends on the presence
of PCI related device tree nodes (disables the PCI clock in the absence
of PCI nodes, keeps the PCI clock enabled in the presence of nodes) --
moving clock acquisition into the peripheral driver isn't possible for
PCI because its initialization takes place before the platform clock
driver gets initialized, thus the clock provider isn't available then
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
adapt the DIU clock initialization to the COMMON_CLK approach:
device tree based clock lookup, prepare and unprepare for clocks,
work with frequencies not dividers, call the appropriate clk_*()
routines and don't access CCM registers
the "best clock" determination now completely relies on the
platform's clock driver to pick a frequency close to what the
caller requests, and merely checks whether the desired frequency
was met (fits the tolerance of the monitor)
this approach shall succeed upon first try in the usual case,
will test a few less desirable yet acceptable frequencies in
edge cases, and will fallback to "best effort" if none of the
previously tried frequencies pass the test
provide a fallback clock lookup approach in case the OF based clock
lookup for the DIU fails, this allows for successful operation in
the presence of an outdated device tree which lacks clock specs
Cc: Anatolij Gustschin <agust@denx.de>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
the setup before the change was
- arch/powerpc/Kconfig had the PPC_CLOCK option, off by default
- depending on the PPC_CLOCK option the arch/powerpc/kernel/clock.c file
was built, which implements the clk.h API but always returns -ENOSYS
unless a platform registers specific callbacks
- the MPC52xx platform selected PPC_CLOCK but did not register any
callbacks, thus all clk.h API calls keep resulting in -ENOSYS errors
(which is OK, all peripheral drivers deal with the situation)
- the MPC512x platform selected PPC_CLOCK and registered specific
callbacks implemented in arch/powerpc/platforms/512x/clock.c, thus
provided real support for the clock API
- no other powerpc platform did select PPC_CLOCK
the situation after the change is
- the MPC512x platform implements the COMMON_CLK interface, and thus the
PPC_CLOCK approach in arch/powerpc/platforms/512x/clock.c has become
obsolete
- the MPC52xx platform still lacks genuine support for the clk.h API
while this is not a change against the previous situation (the error
code returned from COMMON_CLK stubs differs but every call still
results in an error)
- with all references gone, the arch/powerpc/kernel/clock.c wrapper and
the PPC_CLOCK option have become obsolete, as did the clk_interface.h
header file
the switch from PPC_CLOCK to COMMON_CLK is done for all platforms within
the same commit such that multiplatform kernels (the combination of 512x
and 52xx within one executable) keep working
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
this addresses the client side of device tree based clock lookups
add clock specifiers to the mbx, nfc, mscan, sdhc, i2c, axe, diu, viu,
mdio, fec, usb, pata, psc, psc fifo, and pci nodes in the shared
mpc5121.dtsi include
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: devicetree@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Reviewed-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
extend the recently added COMMON_CLK platform support for MPC512x such
that it works with incomplete device tree data which lacks clock specs
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Gerhard Sittig <gsi@denx.de>
[agust@denx.de: moved node macro definitions out of the function body]
Signed-off-by: Anatolij Gustschin <agust@denx.de>
this change implements a clock driver for the MPC512x PowerPC platform
which follows the COMMON_CLK approach and uses common clock drivers
shared with other platforms
this driver implements the publicly announced set of clocks (those
listed in the dt-bindings header file), as well as generates additional
'struct clk' items where the SoC hardware cannot easily get mapped to
the common primitives (shared code) of the clock API, or requires
"intermediate clock nodes" to represent clocks that have both gates and
dividers
the previous PPC_CLOCK implementation is kept in place and remains
active for the moment, the newly introduced CCF clock driver will
receive additional support for backwards compatibility in a subsequent
patch before it gets enabled and will replace the PPC_CLOCK approach
some of the clock items get pre-enabled in the clock driver to not have
them automatically disabled by the underlying clock subsystem because of
their being unused -- this approach is desirable because
- some of the clocks are useful to have for diagnostics and information
despite their not getting claimed by any drivers (CPU, internal and
external RAM, internal busses, boot media)
- some of the clocks aren't claimed by their peripheral drivers yet,
either because of missing driver support or because device tree specs
aren't available yet (but the workarounds will get removed as the
drivers get adjusted and the device tree provides the clock specs)
clkdev registration provides "alias names" for few clock items
- to not break those peripheral drivers which encode their component
index into the name that is used for clock lookup (UART, SPI, USB)
- to not break those drivers which use names for the clock lookup which
were encoded in the previous PPC_CLOCK implementation (NFC, VIU, CAN)
this workaround will get removed as these drivers get adjusted after
device tree based clock lookup has become available
the COMMON_CLK implementation copes with device trees which lack an
oscillator node (backwards compat), the REF clock is then derived from
the IPS bus frequency and multiplier values fetched from hardware
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
this addresses the clock driver aka provider's side of clocks
- introduce a 'clocks' subtree with an 'osc' node for the crystal
or oscillator SoC input (fixed frequency)
- the 'clock@f00' clock-control-module node references the 'osc' for
its input, and is another provider for all the clocks which the
CCM component manages
- prepare for future references to clocks from peripheral nodes
by means of the <&clks ID> syntax and symbolic ID names which a
header file provides
- provide default values with 33MHz oscillator frequency in the
common include (the 66MHz IPS bus already was there), and add
override values for the ifm AC14xx board which deviates from
the reference design (25MHz xtal, 80MHz IPS bus)
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: devicetree@vger.kernel.org
Reviewed-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
A number of situations currently require the heavyweight smp_mb(),
even though there is no need to order prior stores against later
loads. Many architectures have much cheaper ways to handle these
situations, but the Linux kernel currently has no portable way
to make use of them.
This commit therefore supplies smp_load_acquire() and
smp_store_release() to remedy this situation. The new
smp_load_acquire() primitive orders the specified load against
any subsequent reads or writes, while the new smp_store_release()
primitive orders the specifed store against any prior reads or
writes. These primitives allow array-based circular FIFOs to be
implemented without an smp_mb(), and also allow a theoretical
hole in rcu_assign_pointer() to be closed at no additional
expense on most architectures.
In addition, the RCU experience transitioning from explicit
smp_read_barrier_depends() and smp_wmb() to rcu_dereference()
and rcu_assign_pointer(), respectively resulted in substantial
improvements in readability. It therefore seems likely that
replacing other explicit barriers with smp_load_acquire() and
smp_store_release() will provide similar benefits. It appears
that roughly half of the explicit barriers in core kernel code
might be so replaced.
[Changelog by PaulMck]
Reviewed-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Victor Kaplansky <VICTORK@il.ibm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/20131213150640.908486364@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
It is now possible to use the common cpuidle_[un]register() routines
(instead of open-coding them) so do it.
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
pseries cpuidle driver sets dev->state_count to drv->state_count so
the default dev->state_count initialization in cpuidle_enable_device()
(called from cpuidle_register_device()) can be used instead.
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There are much pci compatible with version on existing platforms.
To stop putting version numbers in device tree later, we add a
generic compatible 'fsl,qoriq-pcie'.
The version number is readable directly from a register.
Signed-off-by: Shengzhou Liu <Shengzhou.Liu@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Add elo3-dma-2.dtsi to support the third DMA controller.
This is used on T2080, T4240, B4860, etc.
FSL MPIC v4.3 adds a new discontiguous address range for internal interrupts,
e.g. internal interrupt 0 is at offset 0x200 and thus interrupt number is:
0x200 >> 5 = 16 in the device tree. DMA controller 3 channel 0 internal
interrupt 240 is at offset 0x3a00, and thus the corresponding interrupt
number is: 0x3a00 >> 5 = 464, it's similar for other 7 interrupt numbers
of DMA 3 channels.
Signed-off-by: Shengzhou Liu <Shengzhou.Liu@freescale.com>
Signed-off-by: Hongbo Zhang <hongbo.zhang@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
On Freescale e6500 cores EPCR[DGTMI] controls whether guest supervisor
state can execute TLB management instructions. If EPCR[DGTMI]=0
tlbwe and tlbilx are allowed to execute normally in the guest state.
A hypervisor may choose to virtualize TLB1 and for this purpose it
may use IPROT to protect the entries for being invalidated by the
guest. However, because tlbwe and tlbilx execution in the guest state
are sharing the same bit, it is not possible to have a scenario where
tlbwe is allowed to be executed in guest state and tlbilx traps. When
guest TLB management instructions are allowed to be executed in guest
state the guest cannot use tlbilx to invalidate TLB1 guest entries.
Linux is using tlbilx in the boot code to invalidate the temporary
entries it creates when initializing the MMU. The patch is replacing
the usage of tlbilx in initialization code with tlbwe with VALID bit
cleared.
Linux is also using tlbilx in other contexts (like huge pages or
indirect entries) but removing the tlbilx from the initialization code
offers the possibility to have scenarios under hypervisor which are
not using huge pages or indirect entries.
Signed-off-by: Diana Craciun <Diana.Craciun@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
It was branching to the cleanup part of the non-bolted handler,
which would have been bad if there were any chips with tlbsrx.
that use the bolted handler.
Signed-off-by: Scott Wood <scottwood@freescale.com>
As of commit b81f18e55e ("powerpc/boot:
Only build board support files when required.") the two defconfigs
ep88xc_defconfig and storcenter_defconfig would fail final link as
follows:
WRAP arch/powerpc/boot/dtbImage.ep88xc
arch/powerpc/boot/wrapper.a(mpc8xx.o): In function `mpc885_get_clock':
arch/powerpc/boot/mpc8xx.c:30: undefined reference to `fsl_get_immr'
make[1]: *** [arch/powerpc/boot/dtbImage.ep88xc] Error 1
...and...
WRAP arch/powerpc/boot/cuImage.storcenter
arch/powerpc/boot/cuboot-pq2.o: In function `pq2_platform_fixups':
cuboot-pq2.c:(.text+0x324): undefined reference to `fsl_get_immr'
make[1]: *** [arch/powerpc/boot/cuImage.storcenter] Error 1
We need the fsl-soc board files built for these two platforms.
Cc: Tony Breeds <tony@bakeyournoodle.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Fixes: b81f18e55e ("powerpc/boot: Only build board support files when required.")
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
On P1020, P1021, P1022, and P1023, eLBC event interrupts are routed
to internal interrupt 3 while ELBC error interrupts are routed to
internal interrupt 0. We need to call request_irq for each.
Signed-off-by: Shaohui Xie <Shaohui.Xie@freescale.com>
Signed-off-by: Wang Dongsheng <dongsheng.wang@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
[scottwood@freescale.com: reworded commit message and fixed author]
Signed-off-by: Scott Wood <scottwood@freescale.com>
P1020, P1021, P1022, P1023 when the lbc get error, the error
interrupt will be triggered. The corresponding interrupt is
internal IRQ0. So system have to process the lbc IRQ0 interrupt.
The corresponding lbc general interrupt is internal IRQ3.
Signed-off-by: Wang Dongsheng <dongsheng.wang@freescale.com>
[scottwood@freescale.com: bracketed individual list elements]
Signed-off-by: Scott Wood <scottwood@freescale.com>
Add support for the Motorola/Emerson MVME5100 Single Board Computer.
The MVME5100 is a 6U form factor VME64 computer with:
- A single MPC7410 or MPC750 CPU
- A HAWK Processor Host Bridge (CPU to PCI) and
MultiProcessor Interrupt Controller (MPIC)
- Up to 500Mb of onboard memory
- A M48T37 Real Time Clock (RTC) and Non-Volatile Memory chip
- Two 16550 compatible UARTS
- Two Intel E100 Fast Ethernets
- Two PCI Mezzanine Card (PMC) Slots
- PPCBug Firmware
The HAWK PHB/MPIC is compatible with the MPC10x devices.
There is no onboard disk support. This is usually provided by installing a PMC
in first PMC slot.
This patch revives the board support, it was present in early 2.6
series kernels. The board support in those days was by Matt Porter of
MontaVista Software.
CSC Australia has around 31 of these boards in service. The kernel in use
for the boards is based on 2.6.31. The boards are operated without disks
from a file server.
This patch is based on linux-3.13-rc2 and has been boot tested.
Only boards with 512 Mb of memory are known to work.
Signed-off-by: Stephen Chivers <schivers@csc.com>
Tested-by: Alessio Igor Bogani <alessio.bogani@elettra.eu>
Signed-off-by: Scott Wood <scottwood@freescale.com>
This keeps usage coordinated for hugetlb and indirect entries, which
should make entry selection more predictable and probably improve overall
performance when mixing the two.
Signed-off-by: Scott Wood <scottwood@freescale.com>
There are a few things that make the existing hw tablewalk handlers
unsuitable for e6500:
- Indirect entries go in TLB1 (though the resulting direct entries go in
TLB0).
- It has threads, but no "tlbsrx." -- so we need a spinlock and
a normal "tlbsx". Because we need this lock, hardware tablewalk
is mandatory on e6500 unless we want to add spinlock+tlbsx to
the normal bolted TLB miss handler.
- TLB1 has no HES (nor next-victim hint) so we need software round robin
(TODO: integrate this round robin data with hugetlb/KVM)
- The existing tablewalk handlers map half of a page table at a time,
because IBM hardware has a fixed 1MiB indirect page size. e6500
has variable size indirect entries, with a minimum of 2MiB.
So we can't do the half-page indirect mapping, and even if we
could it would be less efficient than mapping the full page.
- Like on e5500, the linear mapping is bolted, so we don't need the
overhead of supporting nested tlb misses.
Note that hardware tablewalk does not work in rev1 of e6500.
We do not expect to support e6500 rev1 in mainline Linux.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Cc: Mihai Caraman <mihai.caraman@freescale.com>
There is no barrier between something like ioremap() writing to
a PTE, and returning the value to a caller that may then store the
pointer in a place that is visible to other CPUs. Such callers
generally don't perform barriers of their own.
Even if callers of ioremap() and similar things did use barriers,
the most logical choise would be smp_wmb(), which is not
architecturally sufficient when BookE hardware tablewalk is used. A
full sync is specified by the architecture.
For userspace mappings, OTOH, we generally already have an lwsync due
to locking, and if we occasionally take a spurious fault due to not
having a full sync with hardware tablewalk, it will not be fatal
because we will retry rather than oops.
Signed-off-by: Scott Wood <scottwood@freescale.com>
The RELOCATABLE is more flexible and without any alignment restriction.
And it is a superset of DYNAMIC_MEMSTART. So use it by default for
a kdump kernel.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
When booting above the 64M for a secondary cpu, we also face the
same issue as the boot cpu that the PAGE_OFFSET map two different
physical address for the init tlb and the final map. So we have to use
switch_to_as1/restore_to_as0 between the conversion of these two
maps. When restoring to as0 for a secondary cpu, we only need to
return to the caller. So add a new parameter for function
restore_to_as0 for this purpose.
Use LOAD_REG_ADDR_PIC to get the address of variables which may
be used before we set the final map in cams for the secondary cpu.
Move the setting of cams a bit earlier in order to avoid the
unnecessary using of LOAD_REG_ADDR_PIC.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
This is always true for a non-relocatable kernel. Otherwise the kernel
would get stuck. But for a relocatable kernel, it seems a little
complicated. When booting a relocatable kernel, we just align the
kernel start addr to 64M and map the PAGE_OFFSET from there. The
relocation will base on this virtual address. But if this address
is not the same as the memstart_addr, we will have to change the
map of PAGE_OFFSET to the real memstart_addr and do another relocation
again.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
[scottwood@freescale.com: make offset long and non-negative in simple case]
Signed-off-by: Scott Wood <scottwood@freescale.com>
Introduce this function so we can set both the physical and virtual
address for the map in cams. This will be used by the relocation code.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
For a relocatable kernel since it can be loaded at any place, there
is no any relation between the kernel start addr and the memstart_addr.
So we can't calculate the memstart_addr from kernel start addr. And
also we can't wait to do the relocation after we get the real
memstart_addr from device tree because it is so late. So introduce
a new function we can use to get the first memblock address and size
in a very early stage (before machine_init).
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
