diff options
Diffstat (limited to 'arch/sparc/lib/atomic_32.S')
-rw-r--r-- | arch/sparc/lib/atomic_32.S | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/arch/sparc/lib/atomic_32.S b/arch/sparc/lib/atomic_32.S new file mode 100644 index 000000000000..178cbb8ae1b9 --- /dev/null +++ b/arch/sparc/lib/atomic_32.S | |||
@@ -0,0 +1,99 @@ | |||
1 | /* atomic.S: Move this stuff here for better ICACHE hit rates. | ||
2 | * | ||
3 | * Copyright (C) 1996 David S. Miller (davem@caipfs.rutgers.edu) | ||
4 | */ | ||
5 | |||
6 | #include <asm/ptrace.h> | ||
7 | #include <asm/psr.h> | ||
8 | |||
9 | .text | ||
10 | .align 4 | ||
11 | |||
12 | .globl __atomic_begin | ||
13 | __atomic_begin: | ||
14 | |||
15 | #ifndef CONFIG_SMP | ||
16 | .globl ___xchg32_sun4c | ||
17 | ___xchg32_sun4c: | ||
18 | rd %psr, %g3 | ||
19 | andcc %g3, PSR_PIL, %g0 | ||
20 | bne 1f | ||
21 | nop | ||
22 | wr %g3, PSR_PIL, %psr | ||
23 | nop; nop; nop | ||
24 | 1: | ||
25 | andcc %g3, PSR_PIL, %g0 | ||
26 | ld [%g1], %g7 | ||
27 | bne 1f | ||
28 | st %g2, [%g1] | ||
29 | wr %g3, 0x0, %psr | ||
30 | nop; nop; nop | ||
31 | 1: | ||
32 | mov %g7, %g2 | ||
33 | jmpl %o7 + 8, %g0 | ||
34 | mov %g4, %o7 | ||
35 | |||
36 | .globl ___xchg32_sun4md | ||
37 | ___xchg32_sun4md: | ||
38 | swap [%g1], %g2 | ||
39 | jmpl %o7 + 8, %g0 | ||
40 | mov %g4, %o7 | ||
41 | #endif | ||
42 | |||
43 | /* Read asm-sparc/atomic.h carefully to understand how this works for SMP. | ||
44 | * Really, some things here for SMP are overly clever, go read the header. | ||
45 | */ | ||
46 | .globl ___atomic24_add | ||
47 | ___atomic24_add: | ||
48 | rd %psr, %g3 ! Keep the code small, old way was stupid | ||
49 | nop; nop; nop; ! Let the bits set | ||
50 | or %g3, PSR_PIL, %g7 ! Disable interrupts | ||
51 | wr %g7, 0x0, %psr ! Set %psr | ||
52 | nop; nop; nop; ! Let the bits set | ||
53 | #ifdef CONFIG_SMP | ||
54 | 1: ldstub [%g1 + 3], %g7 ! Spin on the byte lock for SMP. | ||
55 | orcc %g7, 0x0, %g0 ! Did we get it? | ||
56 | bne 1b ! Nope... | ||
57 | ld [%g1], %g7 ! Load locked atomic24_t | ||
58 | sra %g7, 8, %g7 ! Get signed 24-bit integer | ||
59 | add %g7, %g2, %g2 ! Add in argument | ||
60 | sll %g2, 8, %g7 ! Transpose back to atomic24_t | ||
61 | st %g7, [%g1] ! Clever: This releases the lock as well. | ||
62 | #else | ||
63 | ld [%g1], %g7 ! Load locked atomic24_t | ||
64 | add %g7, %g2, %g2 ! Add in argument | ||
65 | st %g2, [%g1] ! Store it back | ||
66 | #endif | ||
67 | wr %g3, 0x0, %psr ! Restore original PSR_PIL | ||
68 | nop; nop; nop; ! Let the bits set | ||
69 | jmpl %o7, %g0 ! NOTE: not + 8, see callers in atomic.h | ||
70 | mov %g4, %o7 ! Restore %o7 | ||
71 | |||
72 | .globl ___atomic24_sub | ||
73 | ___atomic24_sub: | ||
74 | rd %psr, %g3 ! Keep the code small, old way was stupid | ||
75 | nop; nop; nop; ! Let the bits set | ||
76 | or %g3, PSR_PIL, %g7 ! Disable interrupts | ||
77 | wr %g7, 0x0, %psr ! Set %psr | ||
78 | nop; nop; nop; ! Let the bits set | ||
79 | #ifdef CONFIG_SMP | ||
80 | 1: ldstub [%g1 + 3], %g7 ! Spin on the byte lock for SMP. | ||
81 | orcc %g7, 0x0, %g0 ! Did we get it? | ||
82 | bne 1b ! Nope... | ||
83 | ld [%g1], %g7 ! Load locked atomic24_t | ||
84 | sra %g7, 8, %g7 ! Get signed 24-bit integer | ||
85 | sub %g7, %g2, %g2 ! Subtract argument | ||
86 | sll %g2, 8, %g7 ! Transpose back to atomic24_t | ||
87 | st %g7, [%g1] ! Clever: This releases the lock as well | ||
88 | #else | ||
89 | ld [%g1], %g7 ! Load locked atomic24_t | ||
90 | sub %g7, %g2, %g2 ! Subtract argument | ||
91 | st %g2, [%g1] ! Store it back | ||
92 | #endif | ||
93 | wr %g3, 0x0, %psr ! Restore original PSR_PIL | ||
94 | nop; nop; nop; ! Let the bits set | ||
95 | jmpl %o7, %g0 ! NOTE: not + 8, see callers in atomic.h | ||
96 | mov %g4, %o7 ! Restore %o7 | ||
97 | |||
98 | .globl __atomic_end | ||
99 | __atomic_end: | ||