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2011-02-15ARM: 6674/1: LPAE: use long long format when printing physical addresses and ↵Will Deacon
ptes For the Kernel to support 2 level and 3 level page tables, physical addresses (and also page table entries) need to be 32 or 64-bits depending upon the configuration. This patch uses the %08llx conversion specifier for physical addresses and page table entries, ensuring that they are cast to (long long) so that common code can be used regardless of the datatype widths. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-12ARM: move cache/processor/fault glue to separate include filesRussell King
This allows the cache/processor/fault glue to be more easily used from assembler code. Tested on Assabet and Tegra 2. Tested-by: Colin Cross <ccross@android.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-11ARM: 6657/1: hw_breakpoint: fix ptrace breakpoint advertising on unsupported ↵Will Deacon
arch The ptrace debug information register was advertising breakpoint and watchpoint resources for unsupported debug architectures. This meant that setting breakpoints on these architectures would appear to succeed, although they would never fire in reality. This patch fixes the breakpoint slot probing so that it returns 0 when running on an unsupported debug architecture. Reported-by: Ulrich Weigand <ulrich.weigand@de.ibm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-11ARM: 6656/1: hw_breakpoint: avoid UNPREDICTABLE behaviour when reading DBGDSCRWill Deacon
Reading baseline CP14 registers, other than DBGDIDR, when the OS Lock is set leads to UNPREDICTABLE behaviour. This patch ensures that we clear the OS lock before accessing anything other than the DBGDIDR, thereby avoiding this behaviour. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-11ARM: pm: add function to set WFI low-power mode for SMP CPUsRussell King
Add a function to set the SCU low-power mode for SMP CPUs. This centralizes this functionality rather than having to expose the SCU register definitions to each platform. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-10ARM: 6654/1: perf/oprofile: fix off-by-one in stack checkRabin Vincent
Since tail is the previous fp - 1, we need to compare the new fp with tail + 1 to ensure that we don't end up passing in the same tail again, in order to avoid a potential infinite loop in the perf interrupt handler (which has been observed to occur). A similar fix seems to be needed in the OProfile code. Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-10ARM: fixup SMP alternatives in modulesRussell King
With certain configurations, we inline the unlock functions in modules, which results in SMP alternatives being created in modules. We need to fix those up when loading a module to prevent undefined instruction faults. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-02ARM: v6k: select clear exclusive code seqences according to V6 variantsRussell King
If CONFIG_CPU_V6 is enabled, then the kernel must support ARMv6 CPUs which don't have the V6K extensions implemented. Always use the dummy store-exclusive method to ensure that the exclusive monitors are cleared. If CONFIG_CPU_V6 is not set, but CONFIG_CPU_32v6K is enabled, then we have the K extensions available on all CPUs we're building support for, so we can use the new clear-exclusive instruction. Acked-by: Tony Lindgren <tony@atomide.com> Tested-by: Sourav Poddar <sourav.poddar@ti.com> Tested-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-02ARM: v6k: introduce CPU_V6K optionRussell King
Introduce a CPU_V6K configuration option for platforms to select if they have a V6K CPU core. This allows us to identify whether we need to support ARMv6 CPUs without the V6K SMP extensions at build time. Currently CPU_V6K is just an alias for CPU_V6, and all places which reference CPU_V6 are replaced by (CPU_V6 || CPU_V6K). Select CPU_V6K from platforms which are known to be V6K-only. Acked-by: Tony Lindgren <tony@atomide.com> Tested-by: Sourav Poddar <sourav.poddar@ti.com> Tested-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-02ARM: bitops: switch set/clear/change bitops to use ldrex/strexRussell King
Switch the set/clear/change bitops to use the word-based exclusive operations, which are only present in a wider range of ARM architectures than the byte-based exclusive operations. Tested record: - Nicolas Pitre: ext3,rw,le - Sourav Poddar: nfs,le - Will Deacon: ext3,rw,le - Tony Lindgren: ext3+nfs,le Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org> Tested-by: Sourav Poddar <sourav.poddar@ti.com> Tested-by: Will Deacon <will.deacon@arm.com> Tested-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-01-31ARM: smp_on_up: allow non-ARM SMP processorsRussell King
Allow non-ARM SMP processors to use the SMP_ON_UP feature. CPUs supporting SMP must have the new CPU ID format, so check for this first. Then check for ARM11MPCore, which fails the MPIDR check. Lastly check the MPIDR reports multiprocessing extensions and that the CPU is part of a multiprocessing system. Cc: <stable@kernel.org> Reported-and-Tested-by: Stephen Boyd <sboyd@codeaurora.org> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-01-31arm: Switch from do_timer() to xtime_update()Torben Hohn
xtime_update takes the xtime_lock itself. Signed-off-by: Torben Hohn <torbenh@gmx.de> Cc: Russell King <linux@arm.linux.org.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: johnstul@us.ibm.com Cc: hch@infradead.org Cc: yong.zhang0@gmail.com LKML-Reference: <20110127145920.23248.75541.stgit@localhost> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-01-25ARM: twd: ensure timer reload is reprogrammed on entry to periodic modeRussell King
Ensure that the twd timer reload value is reprogrammed each time we enter periodic mode. This ensures that the reload value is always reset correctly. Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Colin Cross <ccross@android.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-01-25percpu: align percpu readmostly subsection to cachelineTejun Heo
Currently percpu readmostly subsection may share cachelines with other percpu subsections which may result in unnecessary cacheline bounce and performance degradation. This patch adds @cacheline parameter to PERCPU() and PERCPU_VADDR() linker macros, makes each arch linker scripts specify its cacheline size and use it to align percpu subsections. This is based on Shaohua's x86 only patch. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Shaohua Li <shaohua.li@intel.com>
2011-01-15Merge branch 'devel-stable' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds
* 'devel-stable' of master.kernel.org:/home/rmk/linux-2.6-arm: (161 commits) ARM: pxa: fix building issue of missing physmap.h ARM: mmp: PXA910 drive strength FAST using wrong value ARM: mmp: MMP2 drive strength FAST using wrong value ARM: pxa: fix recursive calls in pxa_low_gpio_chip AT91: Support for gsia18s board AT91: Acme Systems FOX Board G20 board files AT91: board-sam9m10g45ek.c: Remove duplicate inclusion of mach/hardware.h ARM: pxa: fix suspend/resume array index miscalculation ARM: pxa: use cpu_has_ipr() consistently in irq.c ARM: pxa: remove unused variable in clock-pxa3xx.c ARM: pxa: fix warning in zeus.c ARM: sa1111: fix typo in sa1111_retrigger_lowirq() ARM mxs: clkdev related compile fixes ARM i.MX mx31_3ds: Fix MC13783 regulator names ARM: plat-stmp3xxx: irq_data conversion. ARM: plat-spear: irq_data conversion. ARM: plat-orion: irq_data conversion. ARM: plat-omap: irq_data conversion. ARM: plat-nomadik: irq_data conversion. ARM: plat-mxc: irq_data conversion. ... Fix up trivial conflict in arch/arm/plat-omap/gpio.c (Lennert Buytenhek's irq_data conversion clashing with some omap irq updates)
2011-01-15Merge branch 'fixes' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds
* 'fixes' of master.kernel.org:/home/rmk/linux-2.6-arm: ARM: fix missing branch in __error_a ARM: fix /proc/$PID/stack on SMP ARM: Fix build regression on SA11x0, PXA, and H720x targets ARM: 6625/1: use memblock memory regions for "System RAM" I/O resources ARM: fix wrongly patched constants ARM: 6624/1: fix dependency for CONFIG_SMP_ON_UP ARM: 6623/1: Thumb-2: Fix out-of-range offset for Thumb-2 in proc-v7.S ARM: 6622/1: fix dma_unmap_sg() documentation ARM: 6621/1: bitops: remove condition code clobber for CLZ ARM: 6620/1: Change misleading warning when CONFIG_CMDLINE_FORCE is used ARM: 6619/1: nommu: avoid mapping vectors page when !CONFIG_MMU ARM: sched_clock: make minsec argument to clocks_calc_mult_shift() zero ARM: sched_clock: allow init_sched_clock() to be called early ARM: integrator: fix compile warning in cpu.c ARM: 6616/1: Fix ep93xx-fb init/exit annotations ARM: twd: fix display of twd frequency ARM: udelay: prevent math rounding resulting in short udelays
2011-01-15ARM: fix missing branch in __error_aRussell King
When DEBUG_LL is not set, we don't want __error_a re-entering __lookup_machine_type - we want it to go to the error function. This used to be the case before we reorganized the layout for hotplug cpu, as we used to fall through to __error. With the changed layout, we need an explicit branch here instead. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-01-15ARM: fix /proc/$PID/stack on SMPRussell King
Rabin Vincent reports: | On SMP, this BUG() in save_stack_trace_tsk() can be easily triggered | from user space by reading /proc/$PID/stack, where $PID is any pid but | the current process: | | if (tsk != current) { | #ifdef CONFIG_SMP | /* | * What guarantees do we have here that 'tsk' | * is not running on another CPU? | */ | BUG(); | #else Fix this by replacing the BUG() with an entry to terminate the stack trace, returning an empty trace - I'd rather not expose the dwarf unwinder to a volatile stack of a running thread. Reported-by: Rabin Vincent <rabin@rab.in> Tested-by: Rabin Vincent <rabin@rab.in> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-01-14ARM: 6625/1: use memblock memory regions for "System RAM" I/O resourcesDima Zavin
Do not use memory bank info to request the "system ram" resources as they do not track holes created by memblock_remove inside machine's reserve callback. If the removed memory is passed as platform_device's ioresource, then drivers that call request_mem_region would fail due to a conflict with the incorrectly configured system ram resource. Instead, iterate through the regions of memblock.memory and add those as "System RAM" resources. Signed-off-by: Dima Zavin <dima@android.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-01-13mm: unify module_alloc code for vmallocDavid Rientjes
Four architectures (arm, mips, sparc, x86) use __vmalloc_area() for module_init(). Much of the code is duplicated and can be generalized in a globally accessible function, __vmalloc_node_range(). __vmalloc_node() now calls into __vmalloc_node_range() with a range of [VMALLOC_START, VMALLOC_END) for functionally equivalent behavior. Each architecture may then use __vmalloc_node_range() directly to remove the duplication of code. Signed-off-by: David Rientjes <rientjes@google.com> Cc: Christoph Lameter <cl@linux.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13ARM: ecard: irq_data conversion.Lennert Buytenhek
Signed-off-by: Lennert Buytenhek <buytenh@secretlab.ca> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-01-13ARM: core irq_data conversion.Lennert Buytenhek
Signed-off-by: Lennert Buytenhek <buytenh@secretlab.ca>
2011-01-12ARM: 6620/1: Change misleading warning when CONFIG_CMDLINE_FORCE is usedAlexander Holler
When CONFIG_CMDLINE_FORCE is used, the warning Ignoring unrecognised tag 0x54410009 was displayed. Change this to Ignoring tag cmdline (using the default kernel command line) Signed-off-by: Alexander Holler <holler@ahsoftware.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-01-11ARM: 6619/1: nommu: avoid mapping vectors page when !CONFIG_MMUWill Deacon
When running without an MMU, we do not need to install a mapping for the vectors page. Attempting to do so causes a compile-time error because install_special_mapping is not defined. This patch adds compile-time guards to the vector mapping functions so that we can build nommu configurations once more. Acked-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-01-11ARM: sched_clock: make minsec argument to clocks_calc_mult_shift() zeroRussell King
The purpose of the minsec argument is to prevent 64-bit math overflow when the number of cycles is multiplied up. However, the multipler is 32-bit, and in the sched_clock() case, the cycle counter is up to 32-bit as well. So the math can never overflow. With a value of 60, and clock rates greater than 71MHz, the calculated multiplier is unnecessarily reduced in value, which reduces accuracy by maybe 70ppt. It's almost not worth bothering with as the oscillator driving the counter won't be any more than 1ppm - unless you're using a rubidium lamp or caesium fountain frequency standard. So, set the minsec argument to zero. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-01-11ARM: sched_clock: allow init_sched_clock() to be called earlyRussell King
sched_clock is supposed to be initialized early - in the recently added init_early platform hook. However, in doing so we end up calling mod_timer() before the timer lists are initialized, resulting in an oops. Split the initialization in two - the part which the platform calls early which starts things off. The addition of the timer can be delayed until after we have more of the kernel initialized - when the normal time sources are initialized. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-01-11ARM: twd: fix display of twd frequencyRussell King
The fraction of MHz was not being displayed correctly as the calculation was a factor of 10 out. Fix this. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-01-06Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (416 commits) ARM: DMA: add support for DMA debugging ARM: PL011: add DMA burst threshold support for ST variants ARM: PL011: Add support for transmit DMA ARM: PL011: Ensure IRQs are disabled in UART interrupt handler ARM: PL011: Separate hardware FIFO size from TTY FIFO size ARM: PL011: Allow better handling of vendor data ARM: PL011: Ensure error flags are clear at startup ARM: PL011: include revision number in boot-time port printk ARM: vexpress: add sched_clock() for Versatile Express ARM i.MX53: Make MX53 EVK bootable ARM i.MX53: Some bug fix about MX53 MSL code ARM: 6607/1: sa1100: Update platform device registration ARM: 6606/1: sa1100: Fix platform device registration ARM i.MX51: rename IPU irqs ARM i.MX51: Add ipu clock support ARM: imx/mx27_3ds: Add PMIC support ARM: DMA: Replace page_to_dma()/dma_to_page() with pfn_to_dma()/dma_to_pfn() mx51: fix usb clock support MX51: Add support for usb host 2 arch/arm/plat-mxc/ehci.c: fix errors/typos ...
2011-01-06Merge branch 'devel-stable' into develRussell King
Conflicts: arch/arm/mach-pxa/clock.c arch/arm/mach-pxa/clock.h
2011-01-06Merge branch 'pgt' (early part) into develRussell King
2011-01-06Merge branch 'misc' into develRussell King
Conflicts: arch/arm/Kconfig arch/arm/common/Makefile arch/arm/kernel/Makefile arch/arm/kernel/smp.c
2011-01-06Merge branch 'smp' into miscRussell King
Conflicts: arch/arm/kernel/entry-armv.S arch/arm/mm/ioremap.c
2011-01-05Merge branch 'clksrc' into develRussell King
Conflicts: arch/arm/mach-vexpress/v2m.c arch/arm/plat-omap/counter_32k.c arch/arm/plat-versatile/Makefile
2011-01-05Merge branches 'ftrace', 'gic', 'io', 'kexec', 'mod', 'sa11x0', 'sh' and ↵Russell King
'versatile' into devel
2011-01-05Merge commit 'v2.6.37' into perf/coreIngo Molnar
Merge reason: Add the final .37 tree. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-12-24ARM: provide an early platform initialization hookRussell King
This allows platforms to hook into the initialization early to setup things like scheduler clocks, etc. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-24ARM: simplify early machine init hooksRussell King
Rather than storing each machine init hook separately, store a pointer to the machine description record and dereference this instead. This pointer is only available while the init sections are present, which is not a problem as we only use it from init code. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-24ARM: 6538/1: Subarch IRQ handler macros V3Magnus Damm
Per subarch interrupt handler macros V3. This patch breaks out code from the irq_handler macro into arch_irq_handler and arch_irq_handler_default. The macros are put in the header file "entry-macro-multi.S" The arch_irq_handler_default macro is designed to be used by irq_handler in entry-armv.S while arch_irq_handler is suitable for per-subarch use. Signed-off-by: Magnus Damm <damm@opensource.se> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-24ARM: 6532/1: Allow machine to specify it's own IRQ handlers at run-timeeric miao
Normally different ARM platform has different way to decode the IRQ hardware status and demultiplex to the corresponding IRQ handler. This is highly optimized by macro irq_handler in entry-armv.S, and each machine defines their own macro to decode the IRQ number. However, this prevents multiple machine classes to be built into a single kernel. By allowing each machine to specify thier own handler, and making function pointer 'handle_arch_irq' to point to it at run time, this can be solved. And introduce CONFIG_MULTI_IRQ_HANDLER to allow both solutions to work. Comparing with the highly optimized macro of irq_handler, the new function must be written with care not to lose too much performance. And the IPI stuff on SMP is expected to move to the provided arch IRQ handler as well. The assembly code to invoke handle_arch_irq is optimized by Russell King. Signed-off-by: Eric Miao <eric.miao@canonical.com> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-24ARM: 6540/1: Stop irqsoff trace on return to userTodd Android Poynor
If the irqsoff tracer is in use, stop tracing the interrupt disable interval when returning to userspace. Tracing userspace execution time as interrupts disabled time is not helpful for kernel performance analysis purposes. Only do so if the irqsoff tracer is enabled, to avoid overhead for lockdep, which doesn't care. Signed-off-by: Todd Poynor <toddpoynor@google.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-22Merge branch 'devel' of ↵Russell King
git://git.kernel.org/pub/scm/linux/kernel/git/ycmiao/pxa-linux-2.6 into devel-stable
2010-12-22ARM: sched_clock: provide common infrastructure for sched_clock()Russell King
Provide common sched_clock() infrastructure for platforms to use to create a 64-bit ns based sched_clock() implementation from a counter running at a non-variable clock rate. This implementation is based upon maintaining an epoch for the counter and an epoch for the nanosecond time. When we desire a sched_clock() time, we calculate the number of counter ticks since the last epoch update, convert this to nanoseconds and add to the epoch nanoseconds. We regularly refresh these epochs within the counter wrap interval. We perform a similar calculation as above, and store the new epochs. We read and write the epochs in such a way that sched_clock() can easily (and locklessly) detect when an update is in progress, and repeat the loading of these constants when they're known not to be stable. The one caveat is that sched_clock() is not called in the middle of an update. We achieve that by disabling IRQs. Finally, if the clock rate is known at compile time, the counter to ns conversion factors can be specified, allowing sched_clock() to be tightly optimized. We ensure that these factors are correct by providing an initialization function which performs a run-time check. Acked-by: Peter Zijlstra <peterz@infradead.org> Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Tested-by: Will Deacon <will.deacon@arm.com> Tested-by: Mikael Pettersson <mikpe@it.uu.se> Tested-by: Eric Miao <eric.y.miao@gmail.com> Tested-by: Olof Johansson <olof@lixom.net> Tested-by: Jamie Iles <jamie@jamieiles.com> Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-22ARM: pgtable: collect up identity mapping functionsRussell King
We have two places where we create identity mappings - one when we bring secondary CPUs online, and one where we setup some mappings for soft- reboot. Combine these two into a single implementation. Also collect the identity mapping deletion function. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-22ARM: pgtable: remove L2 cache flushes for SMP page table bring-upRussell King
The MMU is always configured to read page tables from the L2 cache so there's little point flushing them out of the L2 cache back to RAM. Remove these flushes. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: SMP: ensure frame pointer is reinitialized for soft-CPU hotplugRussell King
When we soft-CPU hotplug a CPU, we reset the stack pointer and jump back to start_secondary(). This allows us to restart as if the CPU was actually reset. However, we weren't resetting the frame pointer, which could cause problems with backtracing. Reset the frame pointer to zero (which means no parent frame) just like the early assembly code also does. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: SMP: split out software TLB maintainence broadcastingRussell King
smp.c is becoming too large, so split out the TLB maintainence broadcasting into a separate smp_tlb.c file. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: localtimer: clean up local timer on hot unplugRussell King
When a CPU is hot unplugged, the generic tick code cleans up the clock event device, but fails to call down to the device's set_mode function to actually shut the device down. To work around this, we've historically had a local_timer_stop() callback out of the hotplug code. However, this adds needless complexity when we have the clock event device itself available. Explicitly call the clock event device's set_mode function with CLOCK_EVT_MODE_UNUSED, so that the hardware can be cleanly shutdown without any special external callbacks. When/if the generic code is fixed, percpu_timer_stop() can be killed off. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: smp: improve CPU bringup failure diagnosticsRussell King
We used to print a bland error message which gave no clue as to the failure when we failed to bring up a secondary CPU. Resolve this by separating the two failure cases. If boot_secondary() fails, we print a message indicating the returned error code from boot_secondary(): "CPU%u: failed to boot: %d\n", cpu, ret. However, if boot_secondary() succeeded, but the CPU did not appear to mark itself online within the timeout, indicate that it failed to come online: "CPU%u: failed to come online\n", cpu Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: 6516/1: Allow SMP_ON_UP to work with Thumb-2 kernels.Dave Martin
* __fixup_smp_on_up has been modified with support for the THUMB2_KERNEL case. For THUMB2_KERNEL only, fixups are split into halfwords in case of misalignment, since we can't rely on unaligned accesses working before turning the MMU on. No attempt is made to optimise the aligned case, since the number of fixups is typically small, and it seems best to keep the code as simple as possible. * Add a rotate in the fixup_smp code in order to support CPU_BIG_ENDIAN, as suggested by Nicolas Pitre. * Add an assembly-time sanity-check to ALT_UP() to ensure that the content really is the right size (4 bytes). (No check is done for ALT_SMP(). Possibly, this could be fixed by splitting the two uses ot ALT_SMP() (ALT_SMP...SMP_UP versus ALT_SMP...SMP_UP_B) into two macros. In the first case, ALT_SMP needs to expand to >= 4 bytes, not == 4.) * smp_mpidr.h (which implements ALT_SMP()/ALT_UP() manually due to macro limitations) has not been modified: the affected instruction (mov) has no 16-bit encoding, so the correct instruction size is satisfied in this case. * A "mode" parameter has been added to smp_dmb: smp_dmb arm @ assumes 4-byte instructions (for ARM code, e.g. kuser) smp_dmb @ uses W() to ensure 4-byte instructions for ALT_SMP() This avoids assembly failures due to use of W() inside smp_dmb, when assembling pure-ARM code in the vectors page. There might be a better way to achieve this. * Kconfig: make SMP_ON_UP depend on (!THUMB2_KERNEL || !BIG_ENDIAN) i.e., THUMB2_KERNEL is now supported, but only if !BIG_ENDIAN (The fixup code for Thumb-2 currently assumes little-endian order.) Tested using a single generic realview kernel on: ARM RealView PB-A8 (CONFIG_THUMB2_KERNEL={n,y}) ARM RealView PBX-A9 (SMP) Signed-off-by: Dave Martin <dave.martin@linaro.org> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: CPU hotplug: ensure correct ordering of unplugRussell King
Don't call idle_task_exit() with interrupts disabled, and ensure that we have a memory barrier after interrupts are disabled but before signalling that this CPU has shut down. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>