Currently, when the kernel is configured with LPAE support, but the
CPU doesn't support it, the error message is fairly cryptic:
Error: unrecognized/unsupported processor variant (0x561f5811).
This messages is normally shown when there is an issue when comparing
the processor ID (CP15 0, c0, c0) with the values/masks described in
proc-v7.S. However, the same message is displayed when LPAE support is
enabled in the kernel configuration, but not available in the CPU,
after looking at ID_MMFR0 (CP15 0, c0, c1, 4). Having the same error
message is highly misleading.
This commit improves this by showing a different error message when
this situation occurs:
Error: Kernel with LPAE support, but CPU does not support LPAE.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Commit ad6492b8 added much needed memblock_virt_alloc_low() and further
commit 07bacb3 {memblock, bootmem: restore goal for alloc_low} fixed
the issue with low memory limit thanks to Yinghai. But even after all
these fixes, there is still one case where the limit check done with
ARCH_LOW_ADDRESS_LIMIT for low memory fails. Russell pointed out the
issue with 32 bit LPAE machines in below thread.
https://lkml.org/lkml/2014/1/28/364
Since on some LPAE machines where memory start address is beyond 4GB,
the low memory marker in memblock will be set to default
ARCH_LOW_ADDRESS_LIMIT which is wrong. We can fix this by letting
architectures set the ARCH_LOW_ADDRESS_LIMIT using another export
similar to memblock_set_current_limit() but am not sure whether
its worth the trouble. Tell me if you think otherwise.
Rather am just trying to fix that one broken case using
memblock_virt_alloc() in setup code since the memblock.current_limit
is updated appropriately makes it work on all ARM 32 bit machines.
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Strashko, Grygorii <grygorii.strashko@ti.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The pgtbl macro couldn't handle the specific
(TEXT_OFFSET - PG_DIR_SIZE) value that the combination of
MSM platforms and LPAE created:
head.S:163: Error: invalid constant (203000) after fixup
Regardless of whether this combination of configuration options
will work on currently support platforms at run time, make it
at least assemble properly.
Signed-off-by: Christopher Covington <cov@codeaurora.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
__und_usr_thumb function deals with thumb2 opcodes. In case of BE
image, it needs to byteswap half word thumb2 encoded instructions
before further processing them.
Without this fix BE image user-land thread executing first VFP
instruction encoded in thumb2 fails with SIGILL, because kernel
does not recognize instruction and does not enable VFP.
Reported-by: Corey Melton <comelton@cisco.com>
Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org>
Tested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Some SoC have MMIO regions that are shared across orthogonal
subsystems. This commit implements a possible solution for the
thread-safe access of such regions through a spinlock-protected API.
Concurrent access is protected with a single spinlock for the
entire MMIO address space. While this protects shared-registers,
it also serializes access to unrelated/unshared registers.
We add relaxed and non-relaxed variants, by using writel_relaxed and writel,
respectively. The rationale for this is that some users may not require
register write completion but only thread-safe access to a register.
Tested-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Pull ARM updates from Russell King:
"In this set, we have:
- Refactoring of some of the old StrongARM-1100 GPIO code to make
things simpler by Dmitry Eremin-Solenikov
- Read-only and non-executable support for modules on ARM from Laura
Abbot
- Removal of unnecessary set_drvdata() calls in AMBA code
- Some non-executable support for kernel lowmem mappings at the 1MB
section granularity, and dumping of kernel page tables via debugfs
- Some improvements for the timer/clock code on Footbridge platforms,
and cleanup some of the LED code there
- Fix fls/ffs() signatures to match x86 to prevent build warnings,
particularly where these are used with min/max() macros
- Avoid using the bootmem allocator on ARM (patches from Santosh
Shilimkar)
- Various asid/unaligned access updates from Will Deacon"
* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (51 commits)
ARM: SMP implementations are not supposed to return from smp_ops.cpu_die()
ARM: ignore memory below PHYS_OFFSET
Fix select-induced Kconfig warning for ZBOOT_ROM
ARM: fix ffs/fls implementations to match x86
ARM: 7935/1: sa1100: collie: add gpio-keys configuration
ARM: 7932/1: bcm: Add DEBUG_LL console support
ARM: 7929/1: Remove duplicate SCHED_HRTICK config option
ARM: 7928/1: kconfig: select HAVE_EFFICIENT_UNALIGNED_ACCESS for CPUv6+ && MMU
ARM: 7927/1: dcache: select DCACHE_WORD_ACCESS for big-endian CPUs
ARM: 7926/1: mm: flesh out and fix the comments in the ASID allocator
ARM: 7925/1: mm: keep track of last ASID allocation to improve bitmap searching
ARM: 7924/1: mm: don't bother with reserved ttbr0 when running with LPAE
ARM: PCI: add legacy IDE IRQ implementation
ARM: footbridge: cleanup LEDs code
ARM: pgd allocation: retry on failure
ARM: footbridge: add one-shot mode for DC21285 timer
ARM: footbridge: add sched_clock implementation
ARM: 7922/1: l2x0: add Marvell Tauros3 support
ARM: 7877/1: use built-in byte swap function
ARM: 7921/1: mcpm: remove redundant dsb instructions prior to sev
...
Although we allow recovery in this case, this is not supposed to be
the normal path for hotplugging a CPU back in. This path only exists
to serve those rare platforms where it's not possible to power down
the CPU or reset the CPU. This patch causes the kernel to print a
message when a platform uses this path.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
If the kernel is loaded higher in physical memory than normal, and we
calculate PHYS_OFFSET higher than the start of RAM, this leads to
boot problems as we attempt to map part of this RAM into userspace.
Rather than struggle with this, just truncate the mapping.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Pull scheduler changes from Ingo Molnar:
- Add the initial implementation of SCHED_DEADLINE support: a real-time
scheduling policy where tasks that meet their deadlines and
periodically execute their instances in less than their runtime quota
see real-time scheduling and won't miss any of their deadlines.
Tasks that go over their quota get delayed (Available to privileged
users for now)
- Clean up and fix preempt_enable_no_resched() abuse all around the
tree
- Do sched_clock() performance optimizations on x86 and elsewhere
- Fix and improve auto-NUMA balancing
- Fix and clean up the idle loop
- Apply various cleanups and fixes
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (60 commits)
sched: Fix __sched_setscheduler() nice test
sched: Move SCHED_RESET_ON_FORK into attr::sched_flags
sched: Fix up attr::sched_priority warning
sched: Fix up scheduler syscall LTP fails
sched: Preserve the nice level over sched_setscheduler() and sched_setparam() calls
sched/core: Fix htmldocs warnings
sched/deadline: No need to check p if dl_se is valid
sched/deadline: Remove unused variables
sched/deadline: Fix sparse static warnings
m68k: Fix build warning in mac_via.h
sched, thermal: Clean up preempt_enable_no_resched() abuse
sched, net: Fixup busy_loop_us_clock()
sched, net: Clean up preempt_enable_no_resched() abuse
sched/preempt: Fix up missed PREEMPT_NEED_RESCHED folding
sched/preempt, locking: Rework local_bh_{dis,en}able()
sched/clock, x86: Avoid a runtime condition in native_sched_clock()
sched/clock: Fix up clear_sched_clock_stable()
sched/clock, x86: Use a static_key for sched_clock_stable
sched/clock: Remove local_irq_disable() from the clocks
sched/clock, x86: Rewrite cyc2ns() to avoid the need to disable IRQs
...
Add the syscalls needed for supporting scheduling algorithms
with extended scheduling parameters (e.g., SCHED_DEADLINE).
In general, it makes possible to specify a periodic/sporadic task,
that executes for a given amount of runtime at each instance, and is
scheduled according to the urgency of their own timing constraints,
i.e.:
- a (maximum/typical) instance execution time,
- a minimum interval between consecutive instances,
- a time constraint by which each instance must be completed.
Thus, both the data structure that holds the scheduling parameters of
the tasks and the system calls dealing with it must be extended.
Unfortunately, modifying the existing struct sched_param would break
the ABI and result in potentially serious compatibility issues with
legacy binaries.
For these reasons, this patch:
- defines the new struct sched_attr, containing all the fields
that are necessary for specifying a task in the computational
model described above;
- defines and implements the new scheduling related syscalls that
manipulate it, i.e., sched_setattr() and sched_getattr().
Syscalls are introduced for x86 (32 and 64 bits) and ARM only, as a
proof of concept and for developing and testing purposes. Making them
available on other architectures is straightforward.
Since no "user" for these new parameters is introduced in this patch,
the implementation of the new system calls is just identical to their
already existing counterpart. Future patches that implement scheduling
policies able to exploit the new data structure must also take care of
modifying the sched_*attr() calls accordingly with their own purposes.
Signed-off-by: Dario Faggioli <raistlin@linux.it>
[ Rewrote to use sched_attr. ]
Signed-off-by: Juri Lelli <juri.lelli@gmail.com>
[ Removed sched_setscheduler2() for now. ]
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1383831828-15501-3-git-send-email-juri.lelli@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently code has an inverted logic: opcode from user memory
is swapped to a proper endianness only in case of read error.
While normally opcode should be swapped only if it was read
correctly from user memory.
Reviewed-by: Victor Kamensky <victor.kamensky@linaro.org>
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
arch/arm/kernel/perf_event_cpu.c:274:25: warning: incorrect type in assignment (different modifiers)
arch/arm/kernel/perf_event_cpu.c:274:25: expected int ( *init_fn )( ... )
arch/arm/kernel/perf_event_cpu.c:274:25: got void const *const data
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The MPIDR contains specific bitfields(MPIDR.Aff{2..0}) which uniquely
identify a CPU, in addition to some non-identifying information and
reserved bits. The ARM cpu binding defines the 'reg' property to only
contain the affinity bits, and any cpu nodes with other bits set in
their 'reg' entry are skipped.
As such it is not necessary to mask the phys_id with MPIDR_HWID_BITMASK,
and doing so could lead to matching erroneous CPU nodes in the device
tree. This patch removes the masking of the physical identifier.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Enable the compiler intrinsic for byte swapping on arch ARM. This
allows the compiler to detect and be able to optimize out byte
swappings, and has a very modest benefit on vmlinux size (Linaro gcc
4.8):
text data bss dec hex filename
2840310 123932 61960 3026202 2e2d1a vmlinux-lart #orig
2840152 123932 61960 3026044 2e2c7c vmlinux-lart #builtin-bswap
6473120 314840 5616016 12403976 bd4508 vmlinux-mxs #orig
6472586 314848 5616016 12403450 bd42fa vmlinux-mxs #builtin-bswap
7419872 318372 379556 8117800 7bde28 vmlinux-imx_v6_v7 #orig
7419170 318364 379556 8117090 7bdb62 vmlinux-imx_v6_v7 #builtin-bswap
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
These symbols are only referenced in this source file so can be made
static, and the efficiency table is constant data so can be declared as
such. This avoids polluting the global namespace and fixes warnings
from sparse.
The function arch_scale_freq_power() is still not prototyped or static,
this is a separate issue as this is overriding a weak symbol from the
scheduler which neglects to provide a prototype.
Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We have a handy macro to replace open coded __cpuc_flush_dcache_area(()
and outer_clean_range() sequences. Let's use it. No functional change.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Clean up the setup ARM printks a bit. Add printk level to a few
that were missing (CPU: <...> ones, in particular), and switch from
printk(KERN_* ..) to pr_*().
Finally, un-wrap some long lines since it makes it harder to grep the
sources from where an error came from and tweak some cases of indentation.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
