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-rw-r--r--arch/tile/kernel/entry.S22
1 files changed, 5 insertions, 17 deletions
diff --git a/arch/tile/kernel/entry.S b/arch/tile/kernel/entry.S
index fd8dc42..431e9ae6 100644
--- a/arch/tile/kernel/entry.S
+++ b/arch/tile/kernel/entry.S
@@ -38,12 +38,6 @@ STD_ENTRY(kernel_execve)
jrp lr
STD_ENDPROC(kernel_execve)
-/* Delay a fixed number of cycles. */
-STD_ENTRY(__delay)
- { addi r0, r0, -1; bnzt r0, . }
- jrp lr
- STD_ENDPROC(__delay)
-
/*
* We don't run this function directly, but instead copy it to a page
* we map into every user process. See vdso_setup().
@@ -97,23 +91,17 @@ STD_ENTRY(smp_nap)
/*
* Enable interrupts racelessly and then nap until interrupted.
+ * Architecturally, we are guaranteed that enabling interrupts via
+ * mtspr to INTERRUPT_CRITICAL_SECTION only interrupts at the next PC.
* This function's _cpu_idle_nap address is special; see intvec.S.
* When interrupted at _cpu_idle_nap, we bump the PC forward 8, and
* as a result return to the function that called _cpu_idle().
*/
STD_ENTRY(_cpu_idle)
- {
- lnk r0
- movei r1, KERNEL_PL
- }
- {
- addli r0, r0, _cpu_idle_nap - .
- mtspr INTERRUPT_CRITICAL_SECTION, r1
- }
+ movei r1, 1
+ mtspr INTERRUPT_CRITICAL_SECTION, r1
IRQ_ENABLE(r2, r3) /* unmask, but still with ICS set */
- mtspr SPR_EX_CONTEXT_K_1, r1 /* Kernel PL, ICS clear */
- mtspr SPR_EX_CONTEXT_K_0, r0
- iret
+ mtspr INTERRUPT_CRITICAL_SECTION, zero
.global _cpu_idle_nap
_cpu_idle_nap:
nap
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