diff --git a/arch/mips/kernel/smp-cps.c b/arch/mips/kernel/smp-cps.c index 90ecd099c4b0..f832e99ad4c3 100644 --- a/arch/mips/kernel/smp-cps.c +++ b/arch/mips/kernel/smp-cps.c @@ -490,6 +490,7 @@ static void cps_cpu_die(unsigned int cpu) { unsigned core = cpu_data[cpu].core; unsigned int vpe_id = cpu_vpe_id(&cpu_data[cpu]); + ktime_t fail_time; unsigned stat; int err; @@ -516,6 +517,7 @@ static void cps_cpu_die(unsigned int cpu) * state, the latter happening when a JTAG probe is connected * in which case the CPC will refuse to power down the core. */ + fail_time = ktime_add_ms(ktime_get(), 2000); do { mips_cm_lock_other(core, 0); mips_cpc_lock_other(core); @@ -523,9 +525,28 @@ static void cps_cpu_die(unsigned int cpu) stat &= CPC_Cx_STAT_CONF_SEQSTATE_MSK; mips_cpc_unlock_other(); mips_cm_unlock_other(); - } while (stat != CPC_Cx_STAT_CONF_SEQSTATE_D0 && - stat != CPC_Cx_STAT_CONF_SEQSTATE_D2 && - stat != CPC_Cx_STAT_CONF_SEQSTATE_U2); + + if (stat == CPC_Cx_STAT_CONF_SEQSTATE_D0 || + stat == CPC_Cx_STAT_CONF_SEQSTATE_D2 || + stat == CPC_Cx_STAT_CONF_SEQSTATE_U2) + break; + + /* + * The core ought to have powered down, but didn't & + * now we don't really know what state it's in. It's + * likely that its _pwr_up pin has been wired to logic + * 1 & it powered back up as soon as we powered it + * down... + * + * The best we can do is warn the user & continue in + * the hope that the core is doing nothing harmful & + * might behave properly if we online it later. + */ + if (WARN(ktime_after(ktime_get(), fail_time), + "CPU%u hasn't powered down, seq. state %u\n", + cpu, stat >> CPC_Cx_STAT_CONF_SEQSTATE_SHF)) + break; + } while (1); /* Indicate the core is powered off */ bitmap_clear(core_power, core, 1);