Le 19/10/2015 11:44, Petri Gynther a écrit : > BCM7425 CPU Interface Zephyr Processor, pages 5-309 and 5-310 > BCM7428B0 CPU Interface Zephyr Processor, pages 5-337 and 5-338 > > WAIT instruction: > Thread enters wait state. No instructions are executed until an > interrupt occurs. The processor's clocks are stopped if both threads > are in idle mode. > > Description: > Execution of this instruction puts the thread into wait state, an idle > mode in which no instructions are fetched or executed. The thread remains > in wait state until an interrupt occurs that is not masked by the > interrupt mask field in the Status register. Then, if interrupts are > enabled by the IE bit in the Status register, the interrupt is serviced. > The ERET instruction returns to the instruction following the WAIT > instruction. If interrupts are disabled, the processor resumes executing > instructions with the next sequential instruction. > > Programming notes: > The WAIT instruction should be executed while interrupts are disabled > by the IE bit in the Status register. This avoids a potential timing > hazard, which occurs if an interrupt is taken between testing the counter > and executing the WAIT instruction. In this hazard case, the interrupt > will have been completed before the WAIT instruction is executed, so > the processor will remain indefinitely in wait state until the next > interrupt. > > Signed-off-by: Petri Gynther <pgynther@xxxxxxxxxx> Reviewed-by: Florian Fainelli <f.fainelli@xxxxxxxxx> > --- > arch/mips/kernel/idle.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/arch/mips/kernel/idle.c b/arch/mips/kernel/idle.c > index ab1478d..d636c70 100644 > --- a/arch/mips/kernel/idle.c > +++ b/arch/mips/kernel/idle.c > @@ -160,7 +160,6 @@ void __init check_wait(void) > case CPU_BMIPS3300: > case CPU_BMIPS4350: > case CPU_BMIPS4380: > - case CPU_BMIPS5000: > case CPU_CAVIUM_OCTEON: > case CPU_CAVIUM_OCTEON_PLUS: > case CPU_CAVIUM_OCTEON2: > @@ -171,7 +170,9 @@ void __init check_wait(void) > case CPU_XLP: > cpu_wait = r4k_wait; > break; > - > + case CPU_BMIPS5000: > + cpu_wait = r4k_wait_irqoff; > + break; > case CPU_RM7000: > cpu_wait = rm7k_wait_irqoff; > break; > -- Florian
