| Message ID | 20210322155720.2161941-1-bruce.mitchell@linux.vnet.ibm.com |
|---|---|
| State | New |
| Headers | show |
| Series | [linux-next,tag:,next-20210322] ARM: aspeed: Add CPU hotplug callbacks for kexec support | expand |
On 3/22/2021 08:57, Bruce Mitchell wrote: > These callbacks are required for kexec to function. The AST2600 does not > expose any controls for powering down it's CPU cores, so we borrow the > approach taken from socfpga and wait in the idle loop. > > Author: Joel Stanley <joel@jms.id.au> > > Signed-off-by: Bruce Mitchell <bruce.mitchell@linux.vnet.ibm.com> > --- > arch/arm/mach-aspeed/platsmp.c | 20 ++++++++++++++++++++ > 1 file changed, 20 insertions(+) > > diff --git a/arch/arm/mach-aspeed/platsmp.c b/arch/arm/mach-aspeed/platsmp.c > index 2324becf7991..1ae3ff5a9701 100644 > --- a/arch/arm/mach-aspeed/platsmp.c > +++ b/arch/arm/mach-aspeed/platsmp.c > @@ -7,6 +7,8 @@ > #include <linux/of.h> > #include <linux/smp.h> > > +#include <asm/proc-fns.h> > + > #define BOOT_ADDR 0x00 > #define BOOT_SIG 0x04 > > @@ -53,9 +55,27 @@ static void __init aspeed_g6_smp_prepare_cpus(unsigned int max_cpus) > iounmap(base); > } > > +#ifdef CONFIG_HOTPLUG_CPU > +static void aspeed_g6_cpu_die(unsigned int cpu) > +{ > + /* Do WFI. If we wake up early, go back into WFI */ > + while (1) > + cpu_do_idle(); > +} > + > +static int aspeed_g6_cpu_kill(unsigned int cpu) > +{ > + return 1; > +} > +#endif > + > static const struct smp_operations aspeed_smp_ops __initconst = { > .smp_prepare_cpus = aspeed_g6_smp_prepare_cpus, > .smp_boot_secondary = aspeed_g6_boot_secondary, > +#ifdef CONFIG_HOTPLUG_CPU > + .cpu_die = aspeed_g6_cpu_die, > + .cpu_kill = aspeed_g6_cpu_kill, > +#endif > }; > > CPU_METHOD_OF_DECLARE(aspeed_smp, "aspeed,ast2600-smp", &aspeed_smp_ops); > Adding Andrew Jeffery and Eddie James to the CC list.
On 3/22/2021 09:40, Bruce Mitchell wrote: > On 3/22/2021 08:57, Bruce Mitchell wrote: >> These callbacks are required for kexec to function. The AST2600 does not >> expose any controls for powering down it's CPU cores, so we borrow the >> approach taken from socfpga and wait in the idle loop. >> >> Author: Joel Stanley <joel@jms.id.au> >> >> Signed-off-by: Bruce Mitchell <bruce.mitchell@linux.vnet.ibm.com> >> --- >> arch/arm/mach-aspeed/platsmp.c | 20 ++++++++++++++++++++ >> 1 file changed, 20 insertions(+) >> >> diff --git a/arch/arm/mach-aspeed/platsmp.c >> b/arch/arm/mach-aspeed/platsmp.c >> index 2324becf7991..1ae3ff5a9701 100644 >> --- a/arch/arm/mach-aspeed/platsmp.c >> +++ b/arch/arm/mach-aspeed/platsmp.c >> @@ -7,6 +7,8 @@ >> #include <linux/of.h> >> #include <linux/smp.h> >> >> +#include <asm/proc-fns.h> >> + >> #define BOOT_ADDR 0x00 >> #define BOOT_SIG 0x04 >> >> @@ -53,9 +55,27 @@ static void __init >> aspeed_g6_smp_prepare_cpus(unsigned int max_cpus) >> iounmap(base); >> } >> >> +#ifdef CONFIG_HOTPLUG_CPU >> +static void aspeed_g6_cpu_die(unsigned int cpu) >> +{ >> + /* Do WFI. If we wake up early, go back into WFI */ >> + while (1) >> + cpu_do_idle(); >> +} >> + >> +static int aspeed_g6_cpu_kill(unsigned int cpu) >> +{ >> + return 1; >> +} >> +#endif >> + >> static const struct smp_operations aspeed_smp_ops __initconst = { >> .smp_prepare_cpus = aspeed_g6_smp_prepare_cpus, >> .smp_boot_secondary = aspeed_g6_boot_secondary, >> +#ifdef CONFIG_HOTPLUG_CPU >> + .cpu_die = aspeed_g6_cpu_die, >> + .cpu_kill = aspeed_g6_cpu_kill, >> +#endif >> }; >> >> CPU_METHOD_OF_DECLARE(aspeed_smp, "aspeed,ast2600-smp", >> &aspeed_smp_ops); >> > > Adding Andrew Jeffery and Eddie James to the CC list. > Adding linux-kernel@vger.kernel.org and linux-arm-kernel@lists.infradead.org based feedback.
diff --git a/arch/arm/mach-aspeed/platsmp.c b/arch/arm/mach-aspeed/platsmp.c index 2324becf7991..1ae3ff5a9701 100644 --- a/arch/arm/mach-aspeed/platsmp.c +++ b/arch/arm/mach-aspeed/platsmp.c @@ -7,6 +7,8 @@ #include <linux/of.h> #include <linux/smp.h> +#include <asm/proc-fns.h> + #define BOOT_ADDR 0x00 #define BOOT_SIG 0x04 @@ -53,9 +55,27 @@ static void __init aspeed_g6_smp_prepare_cpus(unsigned int max_cpus) iounmap(base); } +#ifdef CONFIG_HOTPLUG_CPU +static void aspeed_g6_cpu_die(unsigned int cpu) +{ + /* Do WFI. If we wake up early, go back into WFI */ + while (1) + cpu_do_idle(); +} + +static int aspeed_g6_cpu_kill(unsigned int cpu) +{ + return 1; +} +#endif + static const struct smp_operations aspeed_smp_ops __initconst = { .smp_prepare_cpus = aspeed_g6_smp_prepare_cpus, .smp_boot_secondary = aspeed_g6_boot_secondary, +#ifdef CONFIG_HOTPLUG_CPU + .cpu_die = aspeed_g6_cpu_die, + .cpu_kill = aspeed_g6_cpu_kill, +#endif }; CPU_METHOD_OF_DECLARE(aspeed_smp, "aspeed,ast2600-smp", &aspeed_smp_ops);
These callbacks are required for kexec to function. The AST2600 does not expose any controls for powering down it's CPU cores, so we borrow the approach taken from socfpga and wait in the idle loop. Author: Joel Stanley <joel@jms.id.au> Signed-off-by: Bruce Mitchell <bruce.mitchell@linux.vnet.ibm.com> --- arch/arm/mach-aspeed/platsmp.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+)