diff options
Diffstat (limited to 'arch/xtensa/kernel/entry.S')
| -rw-r--r-- | arch/xtensa/kernel/entry.S | 60 |
1 files changed, 48 insertions, 12 deletions
diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S index 5082507d5631..aa7f9add7d77 100644 --- a/arch/xtensa/kernel/entry.S +++ b/arch/xtensa/kernel/entry.S @@ -1912,6 +1912,43 @@ ENTRY(system_call) ENDPROC(system_call) +/* + * Spill live registers on the kernel stack macro. + * + * Entry condition: ps.woe is set, ps.excm is cleared + * Exit condition: windowstart has single bit set + * May clobber: a12, a13 + */ + .macro spill_registers_kernel + +#if XCHAL_NUM_AREGS > 16 + call12 1f + _j 2f + retw + .align 4 +1: + _entry a1, 48 + addi a12, a0, 3 +#if XCHAL_NUM_AREGS > 32 + .rept (XCHAL_NUM_AREGS - 32) / 12 + _entry a1, 48 + mov a12, a0 + .endr +#endif + _entry a1, 48 +#if XCHAL_NUM_AREGS % 12 == 0 + mov a8, a8 +#elif XCHAL_NUM_AREGS % 12 == 4 + mov a12, a12 +#elif XCHAL_NUM_AREGS % 12 == 8 + mov a4, a4 +#endif + retw +2: +#else + mov a12, a12 +#endif + .endm /* * Task switch. @@ -1924,21 +1961,20 @@ ENTRY(_switch_to) entry a1, 16 - mov a12, a2 # preserve 'prev' (a2) - mov a13, a3 # and 'next' (a3) + mov a10, a2 # preserve 'prev' (a2) + mov a11, a3 # and 'next' (a3) l32i a4, a2, TASK_THREAD_INFO l32i a5, a3, TASK_THREAD_INFO - save_xtregs_user a4 a6 a8 a9 a10 a11 THREAD_XTREGS_USER + save_xtregs_user a4 a6 a8 a9 a12 a13 THREAD_XTREGS_USER - s32i a0, a12, THREAD_RA # save return address - s32i a1, a12, THREAD_SP # save stack pointer + s32i a0, a10, THREAD_RA # save return address + s32i a1, a10, THREAD_SP # save stack pointer /* Disable ints while we manipulate the stack pointer. */ - movi a14, (1 << PS_EXCM_BIT) | LOCKLEVEL - xsr a14, ps + rsil a14, LOCKLEVEL rsr a3, excsave1 rsync s32i a3, a3, EXC_TABLE_FIXUP /* enter critical section */ @@ -1953,7 +1989,7 @@ ENTRY(_switch_to) /* Flush register file. */ - call0 _spill_registers # destroys a3, a4, and SAR + spill_registers_kernel /* Set kernel stack (and leave critical section) * Note: It's save to set it here. The stack will not be overwritten @@ -1969,13 +2005,13 @@ ENTRY(_switch_to) /* restore context of the task 'next' */ - l32i a0, a13, THREAD_RA # restore return address - l32i a1, a13, THREAD_SP # restore stack pointer + l32i a0, a11, THREAD_RA # restore return address + l32i a1, a11, THREAD_SP # restore stack pointer - load_xtregs_user a5 a6 a8 a9 a10 a11 THREAD_XTREGS_USER + load_xtregs_user a5 a6 a8 a9 a12 a13 THREAD_XTREGS_USER wsr a14, ps - mov a2, a12 # return 'prev' + mov a2, a10 # return 'prev' rsync retw |