diff options
| -rw-r--r-- | Documentation/devicetree/bindings/chosen.txt | 8 | ||||
| -rw-r--r-- | arch/powerpc/kernel/setup_64.c | 17 |
2 files changed, 24 insertions, 1 deletions
diff --git a/Documentation/devicetree/bindings/chosen.txt b/Documentation/devicetree/bindings/chosen.txt index ed838f453f7a..6ae9d82d4c37 100644 --- a/Documentation/devicetree/bindings/chosen.txt +++ b/Documentation/devicetree/bindings/chosen.txt @@ -44,3 +44,11 @@ Implementation note: Linux will look for the property "linux,stdout-path" or on PowerPC "stdout" if "stdout-path" is not found. However, the "linux,stdout-path" and "stdout" properties are deprecated. New platforms should only use the "stdout-path" property. + +linux,booted-from-kexec +----------------------- + +This property is set (currently only on PowerPC, and only needed on +book3e) by some versions of kexec-tools to tell the new kernel that it +is being booted by kexec, as the booting environment may differ (e.g. +a different secondary CPU release mechanism) diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c index 505ec2c698e0..5c03a6a9b054 100644 --- a/arch/powerpc/kernel/setup_64.c +++ b/arch/powerpc/kernel/setup_64.c @@ -340,11 +340,26 @@ void early_setup_secondary(void) #endif /* CONFIG_SMP */ #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC) +static bool use_spinloop(void) +{ + if (!IS_ENABLED(CONFIG_PPC_BOOK3E)) + return true; + + /* + * When book3e boots from kexec, the ePAPR spin table does + * not get used. + */ + return of_property_read_bool(of_chosen, "linux,booted-from-kexec"); +} + void smp_release_cpus(void) { unsigned long *ptr; int i; + if (!use_spinloop()) + return; + DBG(" -> smp_release_cpus()\n"); /* All secondary cpus are spinning on a common spinloop, release them @@ -524,7 +539,7 @@ void __init setup_system(void) * Freescale Book3e parts spin in a loop provided by firmware, * so smp_release_cpus() does nothing for them */ -#if defined(CONFIG_SMP) && !defined(CONFIG_PPC_FSL_BOOK3E) +#if defined(CONFIG_SMP) /* Release secondary cpus out of their spinloops at 0x60 now that * we can map physical -> logical CPU ids */ |