From: Richard Kuo Date: Mon, 31 Oct 2011 23:27:45 +0000 (-0500) Subject: Hexagon: Add bitops support X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=a86a7ce30ac04cfd6775dc9a0114d9c3924e682a;p=linux-beck.git Hexagon: Add bitops support Signed-off-by: Richard Kuo Acked-by: Arnd Bergmann Signed-off-by: Linus Torvalds --- diff --git a/arch/hexagon/include/asm/bitops.h b/arch/hexagon/include/asm/bitops.h new file mode 100644 index 000000000000..d23461e080ff --- /dev/null +++ b/arch/hexagon/include/asm/bitops.h @@ -0,0 +1,301 @@ +/* + * Bit operations for the Hexagon architecture + * + * Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved. + * + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA. + */ + +#ifndef _ASM_BITOPS_H +#define _ASM_BITOPS_H + +#include +#include +#include +#include + +#ifdef __KERNEL__ + +#define smp_mb__before_clear_bit() barrier() +#define smp_mb__after_clear_bit() barrier() + +/* + * The offset calculations for these are based on BITS_PER_LONG == 32 + * (i.e. I get to shift by #5-2 (32 bits per long, 4 bytes per access), + * mask by 0x0000001F) + * + * Typically, R10 is clobbered for address, R11 bit nr, and R12 is temp + */ + +/** + * test_and_clear_bit - clear a bit and return its old value + * @nr: bit number to clear + * @addr: pointer to memory + */ +static inline int test_and_clear_bit(int nr, volatile void *addr) +{ + int oldval; + + __asm__ __volatile__ ( + " {R10 = %1; R11 = asr(%2,#5); }\n" + " {R10 += asl(R11,#2); R11 = and(%2,#0x1f)}\n" + "1: R12 = memw_locked(R10);\n" + " { P0 = tstbit(R12,R11); R12 = clrbit(R12,R11); }\n" + " memw_locked(R10,P1) = R12;\n" + " {if !P1 jump 1b; %0 = mux(P0,#1,#0);}\n" + : "=&r" (oldval) + : "r" (addr), "r" (nr) + : "r10", "r11", "r12", "p0", "p1", "memory" + ); + + return oldval; +} + +/** + * test_and_set_bit - set a bit and return its old value + * @nr: bit number to set + * @addr: pointer to memory + */ +static inline int test_and_set_bit(int nr, volatile void *addr) +{ + int oldval; + + __asm__ __volatile__ ( + " {R10 = %1; R11 = asr(%2,#5); }\n" + " {R10 += asl(R11,#2); R11 = and(%2,#0x1f)}\n" + "1: R12 = memw_locked(R10);\n" + " { P0 = tstbit(R12,R11); R12 = setbit(R12,R11); }\n" + " memw_locked(R10,P1) = R12;\n" + " {if !P1 jump 1b; %0 = mux(P0,#1,#0);}\n" + : "=&r" (oldval) + : "r" (addr), "r" (nr) + : "r10", "r11", "r12", "p0", "p1", "memory" + ); + + + return oldval; + +} + +/** + * test_and_change_bit - toggle a bit and return its old value + * @nr: bit number to set + * @addr: pointer to memory + */ +static inline int test_and_change_bit(int nr, volatile void *addr) +{ + int oldval; + + __asm__ __volatile__ ( + " {R10 = %1; R11 = asr(%2,#5); }\n" + " {R10 += asl(R11,#2); R11 = and(%2,#0x1f)}\n" + "1: R12 = memw_locked(R10);\n" + " { P0 = tstbit(R12,R11); R12 = togglebit(R12,R11); }\n" + " memw_locked(R10,P1) = R12;\n" + " {if !P1 jump 1b; %0 = mux(P0,#1,#0);}\n" + : "=&r" (oldval) + : "r" (addr), "r" (nr) + : "r10", "r11", "r12", "p0", "p1", "memory" + ); + + return oldval; + +} + +/* + * Atomic, but doesn't care about the return value. + * Rewrite later to save a cycle or two. + */ + +static inline void clear_bit(int nr, volatile void *addr) +{ + test_and_clear_bit(nr, addr); +} + +static inline void set_bit(int nr, volatile void *addr) +{ + test_and_set_bit(nr, addr); +} + +static inline void change_bit(int nr, volatile void *addr) +{ + test_and_change_bit(nr, addr); +} + + +/* + * These are allowed to be non-atomic. In fact the generic flavors are + * in non-atomic.h. Would it be better to use intrinsics for this? + * + * OK, writes in our architecture do not invalidate LL/SC, so this has to + * be atomic, particularly for things like slab_lock and slab_unlock. + * + */ +static inline void __clear_bit(int nr, volatile unsigned long *addr) +{ + test_and_clear_bit(nr, addr); +} + +static inline void __set_bit(int nr, volatile unsigned long *addr) +{ + test_and_set_bit(nr, addr); +} + +static inline void __change_bit(int nr, volatile unsigned long *addr) +{ + test_and_change_bit(nr, addr); +} + +/* Apparently, at least some of these are allowed to be non-atomic */ +static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr) +{ + return test_and_clear_bit(nr, addr); +} + +static inline int __test_and_set_bit(int nr, volatile unsigned long *addr) +{ + return test_and_set_bit(nr, addr); +} + +static inline int __test_and_change_bit(int nr, volatile unsigned long *addr) +{ + return test_and_change_bit(nr, addr); +} + +static inline int __test_bit(int nr, const volatile unsigned long *addr) +{ + int retval; + + asm volatile( + "{P0 = tstbit(%1,%2); if (P0.new) %0 = #1; if (!P0.new) %0 = #0;}\n" + : "=&r" (retval) + : "r" (addr[BIT_WORD(nr)]), "r" (nr % BITS_PER_LONG) + : "p0" + ); + + return retval; +} + +#define test_bit(nr, addr) __test_bit(nr, addr) + +/* + * ffz - find first zero in word. + * @word: The word to search + * + * Undefined if no zero exists, so code should check against ~0UL first. + */ +static inline long ffz(int x) +{ + int r; + + asm("%0 = ct1(%1);\n" + : "=&r" (r) + : "r" (x)); + return r; +} + +/* + * fls - find last (most-significant) bit set + * @x: the word to search + * + * This is defined the same way as ffs. + * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32. + */ +static inline long fls(int x) +{ + int r; + + asm("{ %0 = cl0(%1);}\n" + "%0 = sub(#32,%0);\n" + : "=&r" (r) + : "r" (x) + : "p0"); + + return r; +} + +/* + * ffs - find first bit set + * @x: the word to search + * + * This is defined the same way as + * the libc and compiler builtin ffs routines, therefore + * differs in spirit from the above ffz (man ffs). + */ +static inline long ffs(int x) +{ + int r; + + asm("{ P0 = cmp.eq(%1,#0); %0 = ct0(%1);}\n" + "{ if P0 %0 = #0; if !P0 %0 = add(%0,#1);}\n" + : "=&r" (r) + : "r" (x) + : "p0"); + + return r; +} + +/* + * __ffs - find first bit in word. + * @word: The word to search + * + * Undefined if no bit exists, so code should check against 0 first. + * + * bits_per_long assumed to be 32 + * numbering starts at 0 I think (instead of 1 like ffs) + */ +static inline unsigned long __ffs(unsigned long word) +{ + int num; + + asm("%0 = ct0(%1);\n" + : "=&r" (num) + : "r" (word)); + + return num; +} + +/* + * __fls - find last (most-significant) set bit in a long word + * @word: the word to search + * + * Undefined if no set bit exists, so code should check against 0 first. + * bits_per_long assumed to be 32 + */ +static inline unsigned long __fls(unsigned long word) +{ + int num; + + asm("%0 = cl0(%1);\n" + "%0 = sub(#31,%0);\n" + : "=&r" (num) + : "r" (word)); + + return num; +} + +#include +#include + +#include +#include +#include + +#include +#include + +#endif /* __KERNEL__ */ +#endif