diff options
| author | Manuel Lauss <manuel.lauss@gmail.com> | 2013-06-08 19:15:41 +0000 |
|---|---|---|
| committer | Ralf Baechle <ralf@linux-mips.org> | 2013-06-10 17:59:46 +0200 |
| commit | e63a24ddc79cc801766646fb643451ad366a1121 (patch) | |
| tree | cf2b75c0fae6e1ff1e036ae890a890ba8f4fb07e /arch | |
| parent | 317ddd256b9c24b0d78fa8018f80f1e495481a10 (diff) | |
| download | linux-e63a24ddc79cc801766646fb643451ad366a1121.tar.bz2 | |
MIPS: Alchemy: fix wait function
Only an interrupt can wake the core from 'wait', enable interrupts
locally before executing 'wait'.
[ralf@linux-mips.org: This leave the race between an interrupt that's
setting TIF_NEED_RESCHEd and entering the WAIT status. but at least it's
going to bring Alchemy back from the dead, so I'm going to apply this
patch.]
Signed-off-by: Manuel Lauss <manuel.lauss@gmail.com>
Cc: Linux-MIPS <linux-mips@linux-mips.org>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/5408/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/mips/kernel/idle.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/arch/mips/kernel/idle.c b/arch/mips/kernel/idle.c index 3b09b888afa9..0c655deeea4a 100644 --- a/arch/mips/kernel/idle.c +++ b/arch/mips/kernel/idle.c @@ -93,26 +93,27 @@ static void rm7k_wait_irqoff(void) } /* - * The Au1xxx wait is available only if using 32khz counter or - * external timer source, but specifically not CP0 Counter. - * alchemy/common/time.c may override cpu_wait! + * Au1 'wait' is only useful when the 32kHz counter is used as timer, + * since coreclock (and the cp0 counter) stops upon executing it. Only an + * interrupt can wake it, so they must be enabled before entering idle modes. */ static void au1k_wait(void) { + unsigned long c0status = read_c0_status() | 1; /* irqs on */ + __asm__( " .set mips3 \n" " cache 0x14, 0(%0) \n" " cache 0x14, 32(%0) \n" " sync \n" - " nop \n" + " mtc0 %1, $12 \n" /* wr c0status */ " wait \n" " nop \n" " nop \n" " nop \n" " nop \n" " .set mips0 \n" - : : "r" (au1k_wait)); - local_irq_enable(); + : : "r" (au1k_wait), "r" (c0status)); } static int __initdata nowait; |