diff options
-rw-r--r-- | arch/sparc64/kernel/sparc64_ksyms.c | 9 | ||||
-rw-r--r-- | arch/sparc64/lib/Makefile | 2 | ||||
-rw-r--r-- | arch/sparc64/lib/mb.S | 73 | ||||
-rw-r--r-- | include/asm-sparc64/system.h | 49 |
4 files changed, 43 insertions, 90 deletions
diff --git a/arch/sparc64/kernel/sparc64_ksyms.c b/arch/sparc64/kernel/sparc64_ksyms.c index d89fc24808d3..7d9a0f6c437d 100644 --- a/arch/sparc64/kernel/sparc64_ksyms.c +++ b/arch/sparc64/kernel/sparc64_ksyms.c | |||
@@ -403,12 +403,3 @@ EXPORT_SYMBOL(xor_vis_4); | |||
403 | EXPORT_SYMBOL(xor_vis_5); | 403 | EXPORT_SYMBOL(xor_vis_5); |
404 | 404 | ||
405 | EXPORT_SYMBOL(prom_palette); | 405 | EXPORT_SYMBOL(prom_palette); |
406 | |||
407 | /* memory barriers */ | ||
408 | EXPORT_SYMBOL(mb); | ||
409 | EXPORT_SYMBOL(rmb); | ||
410 | EXPORT_SYMBOL(wmb); | ||
411 | EXPORT_SYMBOL(membar_storeload); | ||
412 | EXPORT_SYMBOL(membar_storeload_storestore); | ||
413 | EXPORT_SYMBOL(membar_storeload_loadload); | ||
414 | EXPORT_SYMBOL(membar_storestore_loadstore); | ||
diff --git a/arch/sparc64/lib/Makefile b/arch/sparc64/lib/Makefile index 6201f1040982..40dbeec7e5d6 100644 --- a/arch/sparc64/lib/Makefile +++ b/arch/sparc64/lib/Makefile | |||
@@ -12,7 +12,7 @@ lib-y := PeeCeeI.o copy_page.o clear_page.o strlen.o strncmp.o \ | |||
12 | U1memcpy.o U1copy_from_user.o U1copy_to_user.o \ | 12 | U1memcpy.o U1copy_from_user.o U1copy_to_user.o \ |
13 | U3memcpy.o U3copy_from_user.o U3copy_to_user.o U3patch.o \ | 13 | U3memcpy.o U3copy_from_user.o U3copy_to_user.o U3patch.o \ |
14 | copy_in_user.o user_fixup.o memmove.o \ | 14 | copy_in_user.o user_fixup.o memmove.o \ |
15 | mcount.o ipcsum.o rwsem.o xor.o find_bit.o delay.o mb.o | 15 | mcount.o ipcsum.o rwsem.o xor.o find_bit.o delay.o |
16 | 16 | ||
17 | lib-$(CONFIG_DEBUG_SPINLOCK) += debuglocks.o | 17 | lib-$(CONFIG_DEBUG_SPINLOCK) += debuglocks.o |
18 | lib-$(CONFIG_HAVE_DEC_LOCK) += dec_and_lock.o | 18 | lib-$(CONFIG_HAVE_DEC_LOCK) += dec_and_lock.o |
diff --git a/arch/sparc64/lib/mb.S b/arch/sparc64/lib/mb.S deleted file mode 100644 index 4004f748619f..000000000000 --- a/arch/sparc64/lib/mb.S +++ /dev/null | |||
@@ -1,73 +0,0 @@ | |||
1 | /* mb.S: Out of line memory barriers. | ||
2 | * | ||
3 | * Copyright (C) 2005 David S. Miller (davem@davemloft.net) | ||
4 | */ | ||
5 | |||
6 | /* These are here in an effort to more fully work around | ||
7 | * Spitfire Errata #51. Essentially, if a memory barrier | ||
8 | * occurs soon after a mispredicted branch, the chip can stop | ||
9 | * executing instructions until a trap occurs. Therefore, if | ||
10 | * interrupts are disabled, the chip can hang forever. | ||
11 | * | ||
12 | * It used to be believed that the memory barrier had to be | ||
13 | * right in the delay slot, but a case has been traced | ||
14 | * recently wherein the memory barrier was one instruction | ||
15 | * after the branch delay slot and the chip still hung. The | ||
16 | * offending sequence was the following in sym_wakeup_done() | ||
17 | * of the sym53c8xx_2 driver: | ||
18 | * | ||
19 | * call sym_ccb_from_dsa, 0 | ||
20 | * movge %icc, 0, %l0 | ||
21 | * brz,pn %o0, .LL1303 | ||
22 | * mov %o0, %l2 | ||
23 | * membar #LoadLoad | ||
24 | * | ||
25 | * The branch has to be mispredicted for the bug to occur. | ||
26 | * Therefore, we put the memory barrier explicitly into a | ||
27 | * "branch always, predicted taken" delay slot to avoid the | ||
28 | * problem case. | ||
29 | */ | ||
30 | |||
31 | .text | ||
32 | |||
33 | 99: retl | ||
34 | nop | ||
35 | |||
36 | .globl mb | ||
37 | mb: ba,pt %xcc, 99b | ||
38 | membar #LoadLoad | #LoadStore | #StoreStore | #StoreLoad | ||
39 | .size mb, .-mb | ||
40 | |||
41 | .globl rmb | ||
42 | rmb: ba,pt %xcc, 99b | ||
43 | membar #LoadLoad | ||
44 | .size rmb, .-rmb | ||
45 | |||
46 | .globl wmb | ||
47 | wmb: ba,pt %xcc, 99b | ||
48 | membar #StoreStore | ||
49 | .size wmb, .-wmb | ||
50 | |||
51 | .globl membar_storeload | ||
52 | membar_storeload: | ||
53 | ba,pt %xcc, 99b | ||
54 | membar #StoreLoad | ||
55 | .size membar_storeload, .-membar_storeload | ||
56 | |||
57 | .globl membar_storeload_storestore | ||
58 | membar_storeload_storestore: | ||
59 | ba,pt %xcc, 99b | ||
60 | membar #StoreLoad | #StoreStore | ||
61 | .size membar_storeload_storestore, .-membar_storeload_storestore | ||
62 | |||
63 | .globl membar_storeload_loadload | ||
64 | membar_storeload_loadload: | ||
65 | ba,pt %xcc, 99b | ||
66 | membar #StoreLoad | #LoadLoad | ||
67 | .size membar_storeload_loadload, .-membar_storeload_loadload | ||
68 | |||
69 | .globl membar_storestore_loadstore | ||
70 | membar_storestore_loadstore: | ||
71 | ba,pt %xcc, 99b | ||
72 | membar #StoreStore | #LoadStore | ||
73 | .size membar_storestore_loadstore, .-membar_storestore_loadstore | ||
diff --git a/include/asm-sparc64/system.h b/include/asm-sparc64/system.h index 5e94c05dc2fc..b5417529f6f1 100644 --- a/include/asm-sparc64/system.h +++ b/include/asm-sparc64/system.h | |||
@@ -28,13 +28,48 @@ enum sparc_cpu { | |||
28 | #define ARCH_SUN4C_SUN4 0 | 28 | #define ARCH_SUN4C_SUN4 0 |
29 | #define ARCH_SUN4 0 | 29 | #define ARCH_SUN4 0 |
30 | 30 | ||
31 | extern void mb(void); | 31 | /* These are here in an effort to more fully work around Spitfire Errata |
32 | extern void rmb(void); | 32 | * #51. Essentially, if a memory barrier occurs soon after a mispredicted |
33 | extern void wmb(void); | 33 | * branch, the chip can stop executing instructions until a trap occurs. |
34 | extern void membar_storeload(void); | 34 | * Therefore, if interrupts are disabled, the chip can hang forever. |
35 | extern void membar_storeload_storestore(void); | 35 | * |
36 | extern void membar_storeload_loadload(void); | 36 | * It used to be believed that the memory barrier had to be right in the |
37 | extern void membar_storestore_loadstore(void); | 37 | * delay slot, but a case has been traced recently wherein the memory barrier |
38 | * was one instruction after the branch delay slot and the chip still hung. | ||
39 | * The offending sequence was the following in sym_wakeup_done() of the | ||
40 | * sym53c8xx_2 driver: | ||
41 | * | ||
42 | * call sym_ccb_from_dsa, 0 | ||
43 | * movge %icc, 0, %l0 | ||
44 | * brz,pn %o0, .LL1303 | ||
45 | * mov %o0, %l2 | ||
46 | * membar #LoadLoad | ||
47 | * | ||
48 | * The branch has to be mispredicted for the bug to occur. Therefore, we put | ||
49 | * the memory barrier explicitly into a "branch always, predicted taken" | ||
50 | * delay slot to avoid the problem case. | ||
51 | */ | ||
52 | #define membar_safe(type) \ | ||
53 | do { __asm__ __volatile__("ba,pt %%xcc, 1f\n\t" \ | ||
54 | " membar " type "\n" \ | ||
55 | "1:\n" \ | ||
56 | : : : "memory"); \ | ||
57 | } while (0) | ||
58 | |||
59 | #define mb() \ | ||
60 | membar_safe("#LoadLoad | #LoadStore | #StoreStore | #StoreLoad") | ||
61 | #define rmb() \ | ||
62 | membar_safe("#LoadLoad") | ||
63 | #define wmb() \ | ||
64 | membar_safe("#StoreStore") | ||
65 | #define membar_storeload() \ | ||
66 | membar_safe("#StoreLoad") | ||
67 | #define membar_storeload_storestore() \ | ||
68 | membar_safe("#StoreLoad | #StoreStore") | ||
69 | #define membar_storeload_loadload() \ | ||
70 | membar_safe("#StoreLoad | #LoadLoad") | ||
71 | #define membar_storestore_loadstore() \ | ||
72 | membar_safe("#StoreStore | #LoadStore") | ||
38 | 73 | ||
39 | #endif | 74 | #endif |
40 | 75 | ||