1 #include <asm/assembler.h> 2 #include <asm/unwind.h> 3 4 #if __LINUX_ARM_ARCH__ >= 6 5 .macro bitop, name, instr 6 ENTRY( \name ) 7 UNWIND( .fnstart ) 8 ands ip, r1, #3 9 strneb r1, [ip] @ assert word-aligned 10 mov r2, #1 11 and r3, r0, #31 @ Get bit offset 12 mov r0, r0, lsr #5 13 add r1, r1, r0, lsl #2 @ Get word offset 14 #if __LINUX_ARM_ARCH__ >= 7 && defined(CONFIG_SMP) 15 .arch_extension mp 16 ALT_SMP(W(pldw) [r1]) 17 ALT_UP(W(nop)) 18 #endif 19 mov r3, r2, lsl r3 20 1: ldrex r2, [r1] 21 \instr r2, r2, r3 22 strex r0, r2, [r1] 23 cmp r0, #0 24 bne 1b 25 bx lr 26 UNWIND( .fnend ) 27 ENDPROC(\name ) 28 .endm 29 30 .macro testop, name, instr, store 31 ENTRY( \name ) 32 UNWIND( .fnstart ) 33 ands ip, r1, #3 34 strneb r1, [ip] @ assert word-aligned 35 mov r2, #1 36 and r3, r0, #31 @ Get bit offset 37 mov r0, r0, lsr #5 38 add r1, r1, r0, lsl #2 @ Get word offset 39 mov r3, r2, lsl r3 @ create mask 40 smp_dmb 41 #if __LINUX_ARM_ARCH__ >= 7 && defined(CONFIG_SMP) 42 .arch_extension mp 43 ALT_SMP(W(pldw) [r1]) 44 ALT_UP(W(nop)) 45 #endif 46 1: ldrex r2, [r1] 47 ands r0, r2, r3 @ save old value of bit 48 \instr r2, r2, r3 @ toggle bit 49 strex ip, r2, [r1] 50 cmp ip, #0 51 bne 1b 52 smp_dmb 53 cmp r0, #0 54 movne r0, #1 55 2: bx lr 56 UNWIND( .fnend ) 57 ENDPROC(\name ) 58 .endm 59 #else 60 .macro bitop, name, instr 61 ENTRY( \name ) 62 UNWIND( .fnstart ) 63 ands ip, r1, #3 64 strneb r1, [ip] @ assert word-aligned 65 and r2, r0, #31 66 mov r0, r0, lsr #5 67 mov r3, #1 68 mov r3, r3, lsl r2 69 save_and_disable_irqs ip 70 ldr r2, [r1, r0, lsl #2] 71 \instr r2, r2, r3 72 str r2, [r1, r0, lsl #2] 73 restore_irqs ip 74 ret lr 75 UNWIND( .fnend ) 76 ENDPROC(\name ) 77 .endm 78 79 /** 80 * testop - implement a test_and_xxx_bit operation. 81 * @instr: operational instruction 82 * @store: store instruction 83 * 84 * Note: we can trivially conditionalise the store instruction 85 * to avoid dirtying the data cache. 86 */ 87 .macro testop, name, instr, store 88 ENTRY( \name ) 89 UNWIND( .fnstart ) 90 ands ip, r1, #3 91 strneb r1, [ip] @ assert word-aligned 92 and r3, r0, #31 93 mov r0, r0, lsr #5 94 save_and_disable_irqs ip 95 ldr r2, [r1, r0, lsl #2]! 96 mov r0, #1 97 tst r2, r0, lsl r3 98 \instr r2, r2, r0, lsl r3 99 \store r2, [r1] 100 moveq r0, #0 101 restore_irqs ip 102 ret lr 103 UNWIND( .fnend ) 104 ENDPROC(\name ) 105 .endm 106 #endif 107