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2015-07-27arm64: cmpxchg_dbl: patch in lse instructions when supported by the CPUWill Deacon3-51/+94
On CPUs which support the LSE atomic instructions introduced in ARMv8.1, it makes sense to use them in preference to ll/sc sequences. This patch introduces runtime patching of our cmpxchg_double primitives so that the LSE casp instruction is used instead. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64: cmpxchg: patch in lse instructions when supported by the CPUWill Deacon4-66/+98
On CPUs which support the LSE atomic instructions introduced in ARMv8.1, it makes sense to use them in preference to ll/sc sequences. This patch introduces runtime patching of our cmpxchg primitives so that the LSE cas instruction is used instead. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64: xchg: patch in lse instructions when supported by the CPUWill Deacon1-5/+33
On CPUs which support the LSE atomic instructions introduced in ARMv8.1, it makes sense to use them in preference to ll/sc sequences. This patch introduces runtime patching of our xchg primitives so that the LSE swp instruction (yes, you read right!) is used instead. Reviewed-by: Steve Capper <steve.capper@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64: bitops: patch in lse instructions when supported by the CPUWill Deacon2-21/+45
On CPUs which support the LSE atomic instructions introduced in ARMv8.1, it makes sense to use them in preference to ll/sc sequences. This patch introduces runtime patching of our bitops functions so that LSE atomic instructions are used instead. Reviewed-by: Steve Capper <steve.capper@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64: locks: patch in lse instructions when supported by the CPUWill Deacon1-29/+108
On CPUs which support the LSE atomic instructions introduced in ARMv8.1, it makes sense to use them in preference to ll/sc sequences. This patch introduces runtime patching of our locking functions so that LSE atomic instructions are used for spinlocks and rwlocks. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64: atomics: patch in lse instructions when supported by the CPUWill Deacon6-124/+342
On CPUs which support the LSE atomic instructions introduced in ARMv8.1, it makes sense to use them in preference to ll/sc sequences. This patch introduces runtime patching of atomic_t and atomic64_t routines so that the call-site for the out-of-line ll/sc sequences is patched with an LSE atomic instruction when we detect that the CPU supports it. If binutils is not recent enough to assemble the LSE instructions, then the ll/sc sequences are inlined as though CONFIG_ARM64_LSE_ATOMICS=n. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64: introduce CONFIG_ARM64_LSE_ATOMICS as fallback to ll/sc atomicsWill Deacon6-2/+224
In order to patch in the new atomic instructions at runtime, we need to generate wrappers around the out-of-line exclusive load/store atomics. This patch adds a new Kconfig option, CONFIG_ARM64_LSE_ATOMICS. which causes our atomic functions to branch to the out-of-line ll/sc implementations. To avoid the register spill overhead of the PCS, the out-of-line functions are compiled with specific compiler flags to force out-of-line save/restore of any registers that are usually caller-saved. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64: alternatives: add cpu feature for lse atomicsWill Deacon2-1/+3
Add a CPU feature for the LSE atomic instructions, so that they can be patched in at runtime when we detect that they are supported. Reviewed-by: Steve Capper <steve.capper@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64: elf: advertise 8.1 atomic instructions as new hwcapWill Deacon2-0/+15
The ARM v8.1 architecture introduces new atomic instructions to the A64 instruction set for things like cmpxchg, so advertise their availability to userspace using a hwcap. Reviewed-by: Steve Capper <steve.capper@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64: atomics: move ll/sc atomics into separate header fileWill Deacon2-174/+221
In preparation for the Large System Extension (LSE) atomic instructions introduced by ARM v8.1, move the current exclusive load/store (LL/SC) atomics into their own header file. Reviewed-by: Steve Capper <steve.capper@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64: cpufeature.h: add missing #include of kernel.hWill Deacon1-0/+2
cpufeature.h makes use of DECLARE_BITMAP, which in turn relies on the BITS_TO_LONGS and DIV_ROUND_UP macros. This patch includes kernel.h in cpufeature.h to prevent all users having to do the same thing. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64: rwlocks: don't fail trylock purely due to contentionWill Deacon1-6/+8
STXR can fail for a number of reasons, so don't fail an rwlock trylock operation simply because the STXR reported failure. I'm not aware of any issues with the current code, but this makes it consistent with spin_trylock and also other architectures (e.g. arch/arm). Reported-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27Merge branch 'locking/arch-atomic' of ↵Will Deacon65-1015/+841
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into aarch64/for-next/core Merge in PeterZ's logical atomic ops so that we can implement them in our subsequent LSE atomics.
2015-07-27atomic: Add simple atomic_t testsPeter Zijlstra1-21/+47
Add a few atomic_t tests, gets some compile coverage for the new operations. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27atomic: Replace atomic_{set,clear}_mask() usagePeter Zijlstra14-97/+97
Replace the deprecated atomic_{set,clear}_mask() usage with the now ubiquous atomic_{or,andnot}() functions. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27atomic: Collapse all atomic_{set,clear}_mask definitionsPeter Zijlstra16-174/+25
Move the now generic definitions of atomic_{set,clear}_mask() into linux/atomic.h to avoid endless and pointless repetition. Also, provide an atomic_andnot() wrapper for those few archs that can implement that. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27atomic: Provide atomic_{or,xor,and}Peter Zijlstra29-68/+19
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27tile: Provide atomic_{or,xor,and}Chris Metcalf4-0/+99
Implement atomic logic ops -- atomic_{or,xor,and}. For tilegx, these are relatively straightforward; the architecture provides atomic "or" and "and", both 32-bit and 64-bit. To support xor we provide a loop using "cmpexch". For the older 32-bit tilepro architecture, we have to extend the set of low-level assembly routines to include 32-bit "and", as well as all three 64-bit routines. Somewhat confusingly, some 32-bit versions are already used by the bitops inlines, with parameter types appropriate for bitops, so we have to do a bit of casting to match "int" to "unsigned long". Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: http://lkml.kernel.org/r/1436474297-32187-1-git-send-email-cmetcalf@ezchip.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27h8300: Provide atomic_{or,xor,and}Peter Zijlstra1-95/+40
Implement atomic logic ops -- atomic_{or,xor,and} These will replace the atomic_{set,clear}_mask functions that are available on some archs. Also rework the atomic implementation in terms of CPP macros to avoid the typical repetition -- I seem to have missed this arch the last time around when I did that. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27frv: Rewrite atomic implementationPeter Zijlstra9-355/+259
Mostly complete rewrite of the FRV atomic implementation, instead of using assembly files, use inline assembler. The out-of-line CONFIG option makes a bit of a mess of things, but a little CPP trickery gets that done too. FRV already had the atomic logic ops but under a non standard name, the reimplementation provides the generic names and provides the intermediate form required for the bitops implementation. The slightly inconsistent __atomic32_fetch_##op naming is because __atomic_fetch_##op conlicts with GCC builtin functions. The 64bit atomic ops use the inline assembly %Ln construct to access the low word register (r+1), afaik this construct was not previously used in the kernel and is completely undocumented, but I found it in the FRV GCC code and it seems to work. FRV had a non-standard definition of atomic_{clear,set}_mask() which would work types other than atomic_t, the one user relying on that (arch/frv/kernel/dma.c) got converted to use the new intermediate form. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27x86: Provide atomic_{or,xor,and}Peter Zijlstra3-8/+54
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27s390: Provide atomic_{or,xor,and}Peter Zijlstra1-14/+33
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27xtensa: Provide atomic_{or,xor,and}Peter Zijlstra1-69/+16
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27sparc: Provide atomic_{or,xor,and}Peter Zijlstra5-3/+38
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27sh: Provide atomic_{or,xor,and}Peter Zijlstra4-85/+22
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27powerpc: Provide atomic_{or,xor,and}Peter Zijlstra1-0/+9
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27parisc: Provide atomic_{or,xor,and}Peter Zijlstra1-0/+9
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27mn10300: Provide atomic_{or,xor,and}Peter Zijlstra1-47/+10
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27mips: Provide atomic_{or,xor,and}Peter Zijlstra1-0/+9
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Acked-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27metag: Provide atomic_{or,xor,and}Peter Zijlstra2-42/+17
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27m68k: Provide atomic_{or,xor,and}Peter Zijlstra1-4/+10
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27m32r: Provide atomic_{or,xor,and}Peter Zijlstra1-34/+10
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27ia64: Provide atomic_{or,xor,and}Peter Zijlstra1-4/+22
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27hexagon: Provide atomic_{or,xor,and}Peter Zijlstra1-0/+6
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27blackfin: Provide atomic_{or,xor,and}Peter Zijlstra3-25/+40
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. TODO: use inline asm or at least asm macros to collapse the lot. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27avr32: Provide atomic_{or,xor,and}Peter Zijlstra1-0/+14
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27arm64: Provide atomic_{or,xor,and}Peter Zijlstra1-0/+15
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27arm: Provide atomic_{or,xor,and}Peter Zijlstra1-0/+15
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27arc: Provide atomic_{or,xor,and}Peter Zijlstra1-2/+17
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Acked-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27alpha: Provide atomic_{or,xor,and}Peter Zijlstra1-15/+28
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27atomic: Prepare generic atomic implementation for logic opsPeter Zijlstra1-2/+10
Clean up the #ifdef guards a bit to prepare for architectures to supply their own logic ops. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27arm64: include linux/types.h in asm/spinlock_types.hWill Deacon1-0/+2
Our ticket-based spinlock structures rely on a definition of u16, so include linux/types.h explicitly to ensure the thing compiles. Found by a module build failure in -next: arch/arm64/include/asm/spinlock_types.h:27:2: error: unknown type name 'u16' arch/arm64/include/asm/spinlock_types.h:28:2: error: unknown type name 'u16' arch/arm64/include/asm/spinlock_types.h:33:13: error: expected declaration specifiers or '...' before numeric constant include/linux/spinlock_types.h:21:2: error: unknown type name 'arch_spinlock_t' arch/arm64/include/asm/spinlock.h:34:35: error: unknown type name 'arch_spinlock_t' arch/arm64/include/asm/spinlock.h:65:37: error: unknown type name 'arch_spinlock_t' Reported-by: Russell King <linux@arm.linux.org.uk> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64/BUG: Show explicit backtrace for WARNsDave P Martin1-0/+2
The generic slowpath WARN implementation prints a backtrace, but the report_bug() based implementation does not, opting to print the registers instead which is generally not as useful. Ideally, report_bug() should be fixed to make the behaviour more consistent, but in the meantime this patch generates a backtrace directly from the arm64 backend instead so that this functionality is not lost with the migration to report_bug(). As a side-effect, the backtrace will be outside the oops end marker, but that's hard to avoid without modifying generic code. This patch can go away if report_bug() grows the ability in the future to generate a backtrace directly or call an arch hook at the appropriate time. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64/BUG: Use BRK instruction for generic BUG trapsDave P Martin5-3/+142
Currently, the minimal default BUG() implementation from asm- generic is used for arm64. This patch uses the BRK software breakpoint instruction to generate a trap instead, similarly to most other arches, with the generic BUG code generating the dmesg boilerplate. This allows bug metadata to be moved to a separate table and reduces the amount of inline code at BUG and WARN sites. This also avoids clobbering any registers before they can be dumped. To mitigate the size of the bug table further, this patch makes use of the existing infrastructure for encoding addresses within the bug table as 32-bit offsets instead of absolute pointers. (Note that this limits the kernel size to 2GB.) Traps are registered at arch_initcall time for aarch64, but BUG has minimal real dependencies and it is desirable to be able to generate bug splats as early as possible. This patch redirects all debug exceptions caused by BRK directly to bug_handler() until the full debug exception support has been initialised. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64/debug: Add missing #includesDave P Martin2-0/+5
<asm/debug-monitors.h> relies on <asm/ptrace.h>, but doesn't declare this dependency. This becomes a problem once debug-monitors.h starts getting included all over the place to get the BRK immedates. The missing include of <asm/memory.h> (for UL()) in <asm/esr.h> is also added. The series no longer relies on this, but I spotted it during development and it may as well get fixed. No functional change. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64/debug: Simplify BRK insn opcode declarationsDave P Martin2-25/+10
The way the KGDB_DYN_BRK_INS_BYTEx macros are declared is more complex than it needs to be. Also, the macros are only used in one place, which is arch-specific anyway. This patch refactors the macros to simplify them, and exposes an argument so that we can have a single macro instead of 4. As a side effect, this patch also fixes some anomalous spellings of "KGDB". These changes alter the compile types of some integer constants that are harmless but trigger truncation warnings in gcc when assigning to 32-bit variables. This patch adds an explicit cast for the affected cases. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64/debug: Move BRK ESR template macro into <asm/esr.h>Dave P Martin2-7/+7
It makes sense to keep all the architectural exception syndrome definitions in the same place. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64/debug: More consistent naming for the BRK ESR template macroDave P Martin2-4/+5
The naming of DBG_ESR_VAL_BRK is inconsistent with the way other similar macros are named. This patch makes the naming more consistent, and appends "64" as a reminder that this ESR pattern only matches from AArch64 state. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64/debug: Eliminate magic number from ESR template definitionDave P Martin1-1/+3
<asm/esr.h> has perfectly good constants for defining ESR values already. Let's use them. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64/debug: Mask off all reserved bits from generated ESR valuesDave P Martin1-1/+1
There are only 16 comment bits in a BRK instruction, which correspond to ESR bits 15:0. Bits 24:16 of the ESR are RES0, and might have weird meanings in the future. This code inserts 16 bits of comment in the ESR value instead of 20 (almost certainly a typo in the original code). Signed-off-by: Dave Martin <Dave.Martin@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>