diff options
Diffstat (limited to 'arch/sparc/include/asm/switch_to_32.h')
| -rw-r--r-- | arch/sparc/include/asm/switch_to_32.h | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/arch/sparc/include/asm/switch_to_32.h b/arch/sparc/include/asm/switch_to_32.h new file mode 100644 index 00000000000..e32e82b76ee --- /dev/null +++ b/arch/sparc/include/asm/switch_to_32.h | |||
| @@ -0,0 +1,106 @@ | |||
| 1 | #ifndef __SPARC_SWITCH_TO_H | ||
| 2 | #define __SPARC_SWITCH_TO_H | ||
| 3 | |||
| 4 | #include <asm/smp.h> | ||
| 5 | |||
| 6 | extern struct thread_info *current_set[NR_CPUS]; | ||
| 7 | |||
| 8 | /* | ||
| 9 | * Flush windows so that the VM switch which follows | ||
| 10 | * would not pull the stack from under us. | ||
| 11 | * | ||
| 12 | * SWITCH_ENTER and SWITH_DO_LAZY_FPU do not work yet (e.g. SMP does not work) | ||
| 13 | * XXX WTF is the above comment? Found in late teen 2.4.x. | ||
| 14 | */ | ||
| 15 | #ifdef CONFIG_SMP | ||
| 16 | #define SWITCH_ENTER(prv) \ | ||
| 17 | do { \ | ||
| 18 | if (test_tsk_thread_flag(prv, TIF_USEDFPU)) { \ | ||
| 19 | put_psr(get_psr() | PSR_EF); \ | ||
| 20 | fpsave(&(prv)->thread.float_regs[0], &(prv)->thread.fsr, \ | ||
| 21 | &(prv)->thread.fpqueue[0], &(prv)->thread.fpqdepth); \ | ||
| 22 | clear_tsk_thread_flag(prv, TIF_USEDFPU); \ | ||
| 23 | (prv)->thread.kregs->psr &= ~PSR_EF; \ | ||
| 24 | } \ | ||
| 25 | } while(0) | ||
| 26 | |||
| 27 | #define SWITCH_DO_LAZY_FPU(next) /* */ | ||
| 28 | #else | ||
| 29 | #define SWITCH_ENTER(prv) /* */ | ||
| 30 | #define SWITCH_DO_LAZY_FPU(nxt) \ | ||
| 31 | do { \ | ||
| 32 | if (last_task_used_math != (nxt)) \ | ||
| 33 | (nxt)->thread.kregs->psr&=~PSR_EF; \ | ||
| 34 | } while(0) | ||
| 35 | #endif | ||
| 36 | |||
| 37 | #define prepare_arch_switch(next) do { \ | ||
| 38 | __asm__ __volatile__( \ | ||
| 39 | ".globl\tflush_patch_switch\nflush_patch_switch:\n\t" \ | ||
| 40 | "save %sp, -0x40, %sp; save %sp, -0x40, %sp; save %sp, -0x40, %sp\n\t" \ | ||
| 41 | "save %sp, -0x40, %sp; save %sp, -0x40, %sp; save %sp, -0x40, %sp\n\t" \ | ||
| 42 | "save %sp, -0x40, %sp\n\t" \ | ||
| 43 | "restore; restore; restore; restore; restore; restore; restore"); \ | ||
| 44 | } while(0) | ||
| 45 | |||
| 46 | /* Much care has gone into this code, do not touch it. | ||
| 47 | * | ||
| 48 | * We need to loadup regs l0/l1 for the newly forked child | ||
| 49 | * case because the trap return path relies on those registers | ||
| 50 | * holding certain values, gcc is told that they are clobbered. | ||
| 51 | * Gcc needs registers for 3 values in and 1 value out, so we | ||
| 52 | * clobber every non-fixed-usage register besides l2/l3/o4/o5. -DaveM | ||
| 53 | * | ||
| 54 | * Hey Dave, that do not touch sign is too much of an incentive | ||
| 55 | * - Anton & Pete | ||
| 56 | */ | ||
| 57 | #define switch_to(prev, next, last) do { \ | ||
| 58 | SWITCH_ENTER(prev); \ | ||
| 59 | SWITCH_DO_LAZY_FPU(next); \ | ||
| 60 | cpumask_set_cpu(smp_processor_id(), mm_cpumask(next->active_mm)); \ | ||
| 61 | __asm__ __volatile__( \ | ||
| 62 | "sethi %%hi(here - 0x8), %%o7\n\t" \ | ||
| 63 | "mov %%g6, %%g3\n\t" \ | ||
| 64 | "or %%o7, %%lo(here - 0x8), %%o7\n\t" \ | ||
| 65 | "rd %%psr, %%g4\n\t" \ | ||
| 66 | "std %%sp, [%%g6 + %4]\n\t" \ | ||
| 67 | "rd %%wim, %%g5\n\t" \ | ||
| 68 | "wr %%g4, 0x20, %%psr\n\t" \ | ||
| 69 | "nop\n\t" \ | ||
| 70 | "std %%g4, [%%g6 + %3]\n\t" \ | ||
| 71 | "ldd [%2 + %3], %%g4\n\t" \ | ||
| 72 | "mov %2, %%g6\n\t" \ | ||
| 73 | ".globl patchme_store_new_current\n" \ | ||
| 74 | "patchme_store_new_current:\n\t" \ | ||
| 75 | "st %2, [%1]\n\t" \ | ||
| 76 | "wr %%g4, 0x20, %%psr\n\t" \ | ||
| 77 | "nop\n\t" \ | ||
| 78 | "nop\n\t" \ | ||
| 79 | "nop\n\t" /* LEON needs all 3 nops: load to %sp depends on CWP. */ \ | ||
| 80 | "ldd [%%g6 + %4], %%sp\n\t" \ | ||
| 81 | "wr %%g5, 0x0, %%wim\n\t" \ | ||
| 82 | "ldd [%%sp + 0x00], %%l0\n\t" \ | ||
| 83 | "ldd [%%sp + 0x38], %%i6\n\t" \ | ||
| 84 | "wr %%g4, 0x0, %%psr\n\t" \ | ||
| 85 | "nop\n\t" \ | ||
| 86 | "nop\n\t" \ | ||
| 87 | "jmpl %%o7 + 0x8, %%g0\n\t" \ | ||
| 88 | " ld [%%g3 + %5], %0\n\t" \ | ||
| 89 | "here:\n" \ | ||
| 90 | : "=&r" (last) \ | ||
| 91 | : "r" (&(current_set[hard_smp_processor_id()])), \ | ||
| 92 | "r" (task_thread_info(next)), \ | ||
| 93 | "i" (TI_KPSR), \ | ||
| 94 | "i" (TI_KSP), \ | ||
| 95 | "i" (TI_TASK) \ | ||
| 96 | : "g1", "g2", "g3", "g4", "g5", "g7", \ | ||
| 97 | "l0", "l1", "l3", "l4", "l5", "l6", "l7", \ | ||
| 98 | "i0", "i1", "i2", "i3", "i4", "i5", \ | ||
| 99 | "o0", "o1", "o2", "o3", "o7"); \ | ||
| 100 | } while(0) | ||
| 101 | |||
| 102 | extern void fpsave(unsigned long *fpregs, unsigned long *fsr, | ||
| 103 | void *fpqueue, unsigned long *fpqdepth); | ||
| 104 | extern void synchronize_user_stack(void); | ||
| 105 | |||
| 106 | #endif /* __SPARC_SWITCH_TO_H */ | ||