summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--arch/xtensa/include/asm/traps.h44
-rw-r--r--arch/xtensa/kernel/entry.S60
2 files changed, 76 insertions, 28 deletions
diff --git a/arch/xtensa/include/asm/traps.h b/arch/xtensa/include/asm/traps.h
index 917488a0ab0..f2faa58f9a4 100644
--- a/arch/xtensa/include/asm/traps.h
+++ b/arch/xtensa/include/asm/traps.h
@@ -22,25 +22,37 @@ extern void do_unhandled(struct pt_regs *regs, unsigned long exccause);
static inline void spill_registers(void)
{
-
+#if XCHAL_NUM_AREGS > 16
__asm__ __volatile__ (
- "movi a14, "__stringify((1 << PS_EXCM_BIT) | LOCKLEVEL)"\n\t"
- "mov a12, a0\n\t"
- "rsr a13, sar\n\t"
- "xsr a14, ps\n\t"
- "movi a0, _spill_registers\n\t"
- "rsync\n\t"
- "callx0 a0\n\t"
- "mov a0, a12\n\t"
- "wsr a13, sar\n\t"
- "wsr a14, ps\n\t"
- : :
-#if defined(CONFIG_FRAME_POINTER)
- : "a2", "a3", "a4", "a11", "a12", "a13", "a14", "a15",
+ " call12 1f\n"
+ " _j 2f\n"
+ " retw\n"
+ " .align 4\n"
+ "1:\n"
+ " _entry a1, 48\n"
+ " addi a12, a0, 3\n"
+#if XCHAL_NUM_AREGS > 32
+ " .rept (" __stringify(XCHAL_NUM_AREGS) " - 32) / 12\n"
+ " _entry a1, 48\n"
+ " mov a12, a0\n"
+ " .endr\n"
+#endif
+ " _entry a1, 48\n"
+#if XCHAL_NUM_AREGS % 12 == 0
+ " mov a8, a8\n"
+#elif XCHAL_NUM_AREGS % 12 == 4
+ " mov a12, a12\n"
+#elif XCHAL_NUM_AREGS % 12 == 8
+ " mov a4, a4\n"
+#endif
+ " retw\n"
+ "2:\n"
+ : : : "a12", "a13", "memory");
#else
- : "a2", "a3", "a4", "a7", "a11", "a12", "a13", "a14", "a15",
+ __asm__ __volatile__ (
+ " mov a12, a12\n"
+ : : : "memory");
#endif
- "memory");
}
#endif /* _XTENSA_TRAPS_H */
diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S
index 5082507d563..aa7f9add7d7 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