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2013-01-07ARM: 7616/1: cache-l2x0: aurora: Use writel_relaxed instead of writelGregory CLEMENT
The use of writel instead of writel_relaxed lead to deadlock in some situation (SMP on Armada 370 for instance). The use of writel_relaxed as it was done in the rest of this driver fixes this bug. Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Acked-by: Jason Cooper <jason@lakedaemon.net> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-01-07ARM: 7615/1: cache-l2x0: aurora: Invalidate during clean operation with WT ↵Gregory CLEMENT
enable This patch fixes a bug for Aurora L2 cache controller when the write-through mode is enable. For the clean operation even if we don't have to flush the lines we still need to invalidate them. Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Acked-by: Jason Cooper <jason@lakedaemon.net> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-01-02ARM: 7608/1: l2x0: Only set .set_debug on PL310 r3p0 and earlierRob Herring
PL310 errata work-arounds using .set_debug function are only needed on r3p0 and earlier, so check the rev and only set .set_debug on older revs. Avoiding debug register accesses fixes aborts on non-secure platforms like highbank. It is assumed that non-secure platforms needing these work-arounds have already implemented .set_debug with secure monitor calls. Signed-off-by: Rob Herring <rob.herring@calxeda.com> Acked-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-06ARM: 7547/4: cache-l2x0: add support for Aurora L2 cache ctrlGregory CLEMENT
Aurora Cache Controller was designed to be compatible with the ARM L2 Cache Controller. It comes with some difference or improvement such as: - no cache id part number available through hardware (need to get it by the DT). - always write through mode available. - two flavors of the controller outer cache and system cache (meaning maintenance operations on L1 are broadcasted to the L2 and L2 performs the same operation). - in outer cache mode, the cache maintenance operations are improved and can be done on a range inside a page and are not limited to a cache line. Tested-and-Reviewed-by: Lior Amsalem <alior@marvell.com> Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> Signed-off-by: Yehuda Yitschak <yehuday@marvell.com> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-10-18ARM: 7545/1: cache-l2x0: make outer_cache_fns a field of l2x0_of_dataGregory CLEMENT
Instead of having multiple functions belonging to outer_cache and filling this structure on the fly, use a outer_cache_fns field inside l2x0_of_data and just memcopy it into outer_cache depending of the type of the l2x0 cache. For non DT case, the former code was kept. [rmk: fixed a style issue] Tested-and-Reviewed-by: Yehuda Yitschak <yehuday@marvell.com> Tested-and-Reviewed-by: Lior Amsalem <alior@marvell.com> Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-10-07Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-armLinus Torvalds
Pull ARM updates from Russell King: "This is the first chunk of ARM updates for this merge window. Conflicts are expected in two files - asm/timex.h and mach-integrator/integrator_cp.c. Nothing particularly stands out more than anything else. Most of the growth is down to the opcodes stuff from Dave Martin, which is countered by Rob's patches to use more of the asm-generic headers on ARM." (A few more conflicts grew since then, but it all looked fairly trivial) * 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (44 commits) ARM: 7548/1: include linux/sched.h in syscall.h ARM: 7541/1: Add ARM ERRATA 775420 workaround ARM: ensure vm_struct has its phys_addr member filled in ARM: 7540/1: kexec: Check segment memory addresses ARM: 7539/1: kexec: scan for dtb magic in segments ARM: 7538/1: delay: add registration mechanism for delay timer sources ARM: 7536/1: smp: Formalize an IPI for wakeup ARM: 7525/1: ptrace: use updated syscall number for syscall auditing ARM: 7524/1: support syscall tracing ARM: 7519/1: integrator: convert platform devices to Device Tree ARM: 7518/1: integrator: convert AMBA devices to device tree ARM: 7517/1: integrator: initial device tree support ARM: 7516/1: plat-versatile: add DT support to FPGA IRQ ARM: 7515/1: integrator: check PL010 base address from resource ARM: 7514/1: integrator: call common init function from machine ARM: 7522/1: arch_timers: register a time/cycle counter ARM: 7523/1: arch_timers: enable the use of the virtual timer ARM: 7531/1: mark kernelmode mem{cpy,set} non-experimental ARM: 7520/1: Build dtb files in all target ARM: Fix build warning in arch/arm/mm/alignment.c ...
2012-09-15ARM: 7507/1: cache-l2x0.c: save the final aux ctrl value for resumingYilu Mao
There is a bug if l2x0 controller has been enabled when calling l2x0_init, the aux ctrl register will not be saved in l2x0_saved_regs. Therefore we will use uninitialized l2x0_saved_regs.aux_ctrl for resuming later. In this patch, the aux ctrl value is read and saved after it is initialized. So we have the real value being set for resuming. Link: http://lkml.kernel.org/r/1336046857-24133-1-git-send-email-ylmao@marvell.com Signed-off-by: Yilu Mao <ylmao@marvell.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-09-11ARM: cache-l2x0: add a const qualifierUwe Kleine-König
This prepares *of_device_id.data becoming const. Without this change the following warning would occur: arch/arm/mm/cache-l2x0.c: In function 'l2x0_of_init': arch/arm/mm/cache-l2x0.c:573:7: warning: assignment discards 'const' qualifier from pointer target type [enabled by default] though. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
2012-04-23ARM: 7398/1: l2x0: only write to debug registers on PL310Will Deacon
PL310 errata #588369 and #727915 require writes to the debug registers of the cache controller to work around known problems. Writing these registers on L220 may cause deadlock, so ensure that we only perform this operation when we identify a PL310 at probe time. Cc: stable@vger.kernel.org Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-04-23ARM: 7397/1: l2x0: only apply workaround for erratum #753970 on PL310Will Deacon
The workaround for PL310 erratum #753970 can lead to deadlock on systems with an L220 cache controller. This patch makes the workaround effective only when the cache controller is identified as a PL310 at probe time. Cc: stable@vger.kernel.org Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-01-20ARM: cache-l2x0.c: consistently use u32Russell King
__u32 exists to avoid namespace clashes with userspace programs. It should not be used outside header files, so convert to use u32 instead. Also, don't mix uint32_t and __u32 - use the same type throughout the file for consistency. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-11-21ARM: 7162/1: errata: tidy up Kconfig options for PL310 errata workaroundsWill Deacon
The Kconfig options for the PL310 errata workarounds do not use a consistent naming scheme for either the config option or the bool description. This patch tidies up the options by ensuring that the bool descriptions are prefixed with "PL310 errata:" and the config options are prefixed with PL310_ERRATA_, making it much clearer in menuconfig as to what the workarounds are for. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-10-26Merge branch 'core-locking-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits) rtmutex: Add missing rcu_read_unlock() in debug_rt_mutex_print_deadlock() lockdep: Comment all warnings lib: atomic64: Change the type of local lock to raw_spinlock_t locking, lib/atomic64: Annotate atomic64_lock::lock as raw locking, x86, iommu: Annotate qi->q_lock as raw locking, x86, iommu: Annotate irq_2_ir_lock as raw locking, x86, iommu: Annotate iommu->register_lock as raw locking, dma, ipu: Annotate bank_lock as raw locking, ARM: Annotate low level hw locks as raw locking, drivers/dca: Annotate dca_lock as raw locking, powerpc: Annotate uic->lock as raw locking, x86: mce: Annotate cmci_discover_lock as raw locking, ACPI: Annotate c3_lock as raw locking, oprofile: Annotate oprofilefs lock as raw locking, video: Annotate vga console lock as raw locking, latencytop: Annotate latency_lock as raw locking, timer_stats: Annotate table_lock as raw locking, rwsem: Annotate inner lock as raw locking, semaphores: Annotate inner lock as raw locking, sched: Annotate thread_group_cputimer as raw ... Fix up conflicts in kernel/posix-cpu-timers.c manually: making cputimer->cputime a raw lock conflicted with the ABBA fix in commit bcd5cff7216f ("cputimer: Cure lock inversion").
2011-10-17ARM: 7114/1: cache-l2x0: add resume entry for l2 in secure modeBarry Song
we save the l2x0 registers at the first initialization, and platform codes can get them to restore l2x0 status after wakeup. Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Tested-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-10-17ARM: 7090/1: CACHE-L2X0: filter start address can be 0 and is often 0Barry Song
this patch fixes the error in Rob Herring's ARM: 7009/1: l2x0: Add OF based initialization http://www.spinics.net/lists/arm-kernel/msg131123.html it has been in rmk/for-next with commit 41c86ff5b Cc: Shawn Guo <shawn.guo@linaro.org> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Barry Song <Baohua.Song@csr.com> Acked-by: Rob Herring <robherring2@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-10-17ARM: 7089/1: L2X0: add explicit cpu_relax() for busy wait loopBarry Song
using cpu_relax in busy loops is a well-known idiom in the kernel. It's more for documentation purposes than technically needed here. Signed-off-by: Barry Song <Baohua.Song@csr.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Jamie Iles <jamie@jamieiles.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-10-17ARM: 7009/1: l2x0: Add OF based initializationRob Herring
This adds probing for ARM L2x0 cache controllers via device tree. Support includes the L210, L220, and PL310 controllers. The binding allows setting up cache RAM latencies and filter addresses (PL310 only). Signed-off-by: Rob Herring <rob.herring@calxeda.com> Acked-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: Barry Song <21cnbao@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-09-13locking, ARM: Annotate low level hw locks as rawThomas Gleixner
Annotate the low level hardware locks which must not be preempted. In mainline this change documents the low level nature of the lock - otherwise there's no functional difference. Lockdep and Sparse checking will work as usual. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-09-07ARM: 7080/1: l2x0: make sure I&D are not locked down on initLinus Walleij
Fighting unfixed U-Boots and other beasts that may the cache in a locked-down state when starting the kernel, we make sure to disable all cache lock-down when initializing the l2x0 so we are in a known state. Cc: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com> Cc: Rabin Vincent <rabin.vincent@stericsson.com> Cc: Adrian Bunk <adrian.bunk@movial.com> Cc: Rob Herring <robherring2@gmail.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Reported-by: Jan Rinze <janrinze@gmail.com> Tested-by: Robert Marklund <robert.marklund@stericsson.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-07-06ARM: 6987/1: l2x0: fix disabling function to avoid deadlockWill Deacon
The l2x0_disable function attempts to writel with the l2x0_lock held. This results in deadlock when the writel contains an outer_sync call for the platform since the l2x0_lock is already held by the disable function. A further problem is that disabling the L2 without flushing it first can lead to the spin_lock operation becoming visible after the spin_unlock, causing any subsequent L2 maintenance to deadlock. This patch replaces the writel with a call to writel_relaxed in the disabling code and adds a flush before disabling in the control register, preventing livelock from occurring. 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>
2011-03-16Merge branch 'misc' into develRussell King
Conflicts: arch/arm/Kconfig
2011-03-09ARM: 6795/1: l2x0: Errata fix for flush by Way operation can cause data corruptiSantosh Shilimkar
PL310 implements the Clean & Invalidate by Way L2 cache maintenance operation (offset 0x7FC). This operation runs in background so that PL310 can handle normal accesses while it is in progress. Under very rare circumstances, due to this erratum, write data can be lost when PL310 treats a cacheable write transaction during a Clean & Invalidate by Way operation. Workaround: Disable Write-Back and Cache Linefill (Debug Control Register) Clean & Invalidate by Way (0x7FC) Re-enable Write-Back and Cache Linefill (Debug Control Register) This patch also removes any OMAP dependency on PL310 Errata's Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-19ARM: 6741/1: errata: pl310 cache sync operation may be faultySrinidhi Kasagar
The effect of cache sync operation is to drain the store buffer and wait for all internal buffers to be empty. In normal conditions, store buffer is able to merge the normal memory writes within its 32-byte data buffers. Due to this erratum present in r3p0, the effect of cache sync operation on the store buffer still remains when the operation completes. This means that the store buffer is always asked to drain and this prevents it from merging any further writes. This can severely affect performance on the write traffic esp. on Normal memory NC one. The proposed workaround is to replace the normal offset of cache sync operation(0x730) by another offset targeting an unmapped PL310 register 0x740. Signed-off-by: srinidhi kasagar <srinidhi.kasagar@stericsson.com> Acked-by: Linus Walleij <linus.walleij@stericsson.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-10-26ARM: l2x0: Optimise the range based operationsSantosh Shilimkar
For the big buffers which are in excess of cache size, the maintaince operations by PA are very slow. For such buffers the maintainace operations can be speeded up by using the WAY based method. Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Linus Walleij <linus.walleij@stericsson.com>
2010-10-26ARM: l2x0: Determine the cache sizeSantosh Shilimkar
The cache size is needed for to optimise range based maintainance operations Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Linus Walleij <linus.walleij@stericsson.com>
2010-10-26arm: Implement l2x0 cache disable functionsThomas Gleixner
Add flush_all, inv_all and disable functions to the l2x0 code. These functions are called from kexec code to prevent random crashes in the new kernel. Platforms like OMAP which control L2 enable/disable via SMI mode can override the outer_cache.disable() function to implement their own. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Linus Walleij <linus.walleij@stericsson.com>
2010-10-26ARM: Improve the L2 cache performance when PL310 is usedCatalin Marinas
With this L2 cache controller, the cache maintenance by PA and sync operations are atomic and do not require a "wait" loop. This patch conditionally defines the cache_wait() function. Since L2x0 cache controllers do not work with ARMv7 CPUs, the patch automatically enables CACHE_PL310 when only CPU_V7 is defined. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2010-07-29ARM: 6272/1: Convert L2x0 to use the IO relaxed operationsCatalin Marinas
This patch is in preparation for a subsequent patch which adds barriers to the I/O accessors. Since the mandatory barriers may do an L2 cache sync, this patch avoids a recursive call into l2x0_cache_sync() via the write*() accessors and wmb() and a call into l2x0_cache_sync() with the l2x0_lock held. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-07-09ARM: 6210/1: Do not rely on reset defaults of L2X0_AUX_CTRLSascha Hauer
On i.MX35 the L2X0_AUX_CTRL register does not have sensible reset default values. Allow them to be overwritten with the aux_val/aux_mask arguments passed to l2x0_init(). Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-05-17Merge branch 'devel-stable' into develRussell King
Conflicts: arch/arm/Kconfig arch/arm/include/asm/system.h arch/arm/mm/Kconfig
2010-05-15ARM: 6094/1: Extend cache-l2x0 to support the 16-way PL310Jason McMullan
The L310 cache controller's interface is almost identical to the L210. One major difference is that the PL310 can have up to 16 ways. This change uses the cache's part ID and the Associativity bits in the AUX_CTRL register to determine the number of ways. Also, this version prints out the CACHE_ID and AUX_CTRL registers. Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Jason S. McMullan <jason.mcmullan@netronome.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-03-25ARM: 5995/1: ARM: Add L2x0 outer_sync() support (3/4)Catalin Marinas
The L2x0 cache controllers need to explicitly drain their write buffer even for Normal Noncacheable memory accesses. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-02-15ARM: 5919/1: ARM: L2 : Errata 588369: Clean & Invalidate do not invalidate ↵Santosh Shilimkar
clean lines This patch implements the work-around for the errata 588369.The secure API is used to alter L2 debug register because of trust-zone. This version updated with comments from Russell and Catalin and generated against 2.6.33-rc6 mainline kernel. Detail comments can be found: http://www.spinics.net/lists/linux-omap/msg23431.html Signed-off-by: Woodruff Richard <r-woodruff2@ti.com> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-02-15ARM: 5916/1: ARM: L2 : Add maintainace by line helper functionsSantosh Shilimkar
This patch adds the cache maintainance by line helper functions. Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-12-14Merge branch 'pending-l2x0' into cacheRussell King
2009-12-14ARM: cache-l2x0: make better use of background cache handlingRussell King
There's no point having the hardware support background operations if we issue a cache operation, and then wait for it to complete before calculating the address of the next operation. We gain no advantage in the cache controller stalling the bus until completion. What we should be doing is using the 'wait' time productively by calculating the address of the next operation, and only then waiting for the previous operation to complete. This means that cache operations can occur in parallel with the CPU calculating the next address. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
2009-12-14ARM: cache-l2x0: avoid taking spinlock for every iterationRussell King
Taking the spinlock for every iteration is very expensive; instead, batch iterations up into 4K blocks, releasing and reacquiring the spinlock between each block. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
2009-12-03ARM: 5845/1: l2x0: check whether l2x0 already enabledSrinidhi Kasagar
If running in non-secure mode accessing some registers of l2x0 will fault. So check if l2x0 is already enabled, if so do not access those secure registers. Signed-off-by: srinidhi kasagar <srinidhi.kasagar@stericsson.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-09-06[ARM] Convert asm/io.h to linux/io.hRussell King
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-09-17[ARM] 4568/1: fix l2x0 cache invalidate handling of unaligned addressesRui Sousa
The l2x0_inv_range() function doesn't handle unaligned addresses correctly. It's necessary to clean the cache lines that are at the start and end of the invalidate range, if the addresses are not aligned, to prevent corruption of other data sharing the same cache line. Signed-off-by: Rui Sousa <rui.p.m.sousa@gmail.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-07-20[ARM] 4500/1: Add locking around the background L2x0 cache operationsCatalin Marinas
The background operations of the L2x0 cache controllers are aborted if another operation is issued on the same or different core. This patch protects the maintenance operation issuing/polling with a spinlock. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-02-11[ARM] 4135/1: Add support for the L210/L220 cache controllersCatalin Marinas
This patch adds the support for the L210/L220 (outer) cache controller. The cache range operations are done by index/way since L2 cache controller only accepts physical addresses. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>