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* ARC: [optim] uaccess __{get,put}_user() optimisedVineet Gupta2013-02-11
| | | | | | | | | | | | | | | | | | | | | | | | Override asm-generic implementations. We basically gain on 2 fronts * checks for alignment no longer needed as we are only doing "unit" sized copies. (Careful observer could argue that While the kernel buffers are aligned, the user buffer in theory might not be - however in that case the user space is already broken when it tries to deref a hword/word straddling word boundary - so we are not making it any worse). * __copy_{to,from}_user( ) returns bytes that couldn't be copied, whereas get_user() returns 0 for success or -EFAULT (not size). Thus the code to do leftover bytes calculation can be avoided as well. The savings were significant: ~17k of code. bloat-o-meter vmlinux_uaccess_pre vmlinux_uaccess_post add/remove: 0/4 grow/shrink: 8/118 up/down: 1262/-18758 (-17496) ^^^^^^^^^ Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
* ARC: uaccess friendsVineet Gupta2013-02-11
| | | | Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: Atomic/bitops/cmpxchg/barriersVineet Gupta2013-02-11
| | | | | | | This covers the UP / SMP (with no hardware assist for atomic r-m-w) as well as ARC700 LLOCK/SCOND insns based. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: irqflags - Interrupt enabling/disabling at in-core intcVineet Gupta2013-02-11
| | | | | | | | | | | | | | | | | | | | ARC700 has an in-core intc which provides 2 priorities (a.k.a.) "levels" of interrupts (per IRQ) hencforth referred to as L1/L2 interrupts. CPU flags register STATUS32 has Interrupt Enable bits per level (E1/E2) to globally enable (or disable) all IRQs at a level. Hence the implementation of arch_local_irq_{save,restore,enable,disable}( ) The STATUS32 reg can be r/w only using the AUX Interface of ARC, hence the use of LR/SR instructions. Further, E1/E2 bits in there can only be updated using the FLAG insn. The intc supports 32 interrupts - and per IRQ enabling is controlled by a bit in the AUX_IENABLE register, hence the implmentation of arch_{,un}mask_irq( ) routines. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Thomas Gleixner <tglx@linutronix.de>
* ARC: Build system: Makefiles, Kconfig, Linker scriptVineet Gupta2013-02-11
| | | | | | | | | | | | | | | | | | | | Arnd in his review pointed out that arch Kconfig organisation has several deficiencies: * Build time entries for things which can be runtime extracted from DT (e.g. SDRAM size, core clk frequency..) * Not multi-platform-image-build friendly (choice .. endchoice constructs) * cpu variants support (750/770) is exclusive. The first 2 have been fixed in subsequent patches. Due to the nature of the 750 and 770, it is not possible to build for both together, w/o special runtime glue code which would hurt performance. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Sam Ravnborg <sam@ravnborg.org> Acked-by: Sam Ravnborg <sam@ravnborg.org>
* ARC: Generic HeadersVineet Gupta2013-01-28
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>