From 05774088391c7430f6a4c1d5d18196ef17bb3ba9 Mon Sep 17 00:00:00 2001 From: Stefano Stabellini Date: Tue, 21 May 2013 14:24:11 +0000 Subject: arm: introduce psci_smp_ops Rename virt_smp_ops to psci_smp_ops and move them to arch/arm/kernel/psci_smp.c. Remove mach-virt/platsmp.c, now unused. Compile psci_smp if CONFIG_ARM_PSCI and CONFIG_SMP. Add a cpu_die smp_op based on psci_ops.cpu_off. Initialize PSCI before setting smp_ops in setup_arch. If PSCI is available on the platform, prefer psci_smp_ops over the platform smp_ops. Signed-off-by: Stefano Stabellini Acked-by: Will Deacon CC: arnd@arndb.de CC: marc.zyngier@arm.com CC: linux@arm.linux.org.uk CC: nico@linaro.org CC: rob.herring@calxeda.com --- arch/arm/kernel/psci_smp.c | 84 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 84 insertions(+) create mode 100644 arch/arm/kernel/psci_smp.c (limited to 'arch/arm/kernel/psci_smp.c') diff --git a/arch/arm/kernel/psci_smp.c b/arch/arm/kernel/psci_smp.c new file mode 100644 index 000000000000..23a11424c568 --- /dev/null +++ b/arch/arm/kernel/psci_smp.c @@ -0,0 +1,84 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * Copyright (C) 2012 ARM Limited + * + * Author: Will Deacon + */ + +#include +#include +#include +#include + +#include +#include + +/* + * psci_smp assumes that the following is true about PSCI: + * + * cpu_suspend Suspend the execution on a CPU + * @state we don't currently describe affinity levels, so just pass 0. + * @entry_point the first instruction to be executed on return + * returns 0 success, < 0 on failure + * + * cpu_off Power down a CPU + * @state we don't currently describe affinity levels, so just pass 0. + * no return on successful call + * + * cpu_on Power up a CPU + * @cpuid cpuid of target CPU, as from MPIDR + * @entry_point the first instruction to be executed on return + * returns 0 success, < 0 on failure + * + * migrate Migrate the context to a different CPU + * @cpuid cpuid of target CPU, as from MPIDR + * returns 0 success, < 0 on failure + * + */ + +extern void secondary_startup(void); + +static int __cpuinit psci_boot_secondary(unsigned int cpu, + struct task_struct *idle) +{ + if (psci_ops.cpu_on) + return psci_ops.cpu_on(cpu_logical_map(cpu), + __pa(secondary_startup)); + return -ENODEV; +} + +#ifdef CONFIG_HOTPLUG_CPU +void __ref psci_cpu_die(unsigned int cpu) +{ + const struct psci_power_state ps = { + .type = PSCI_POWER_STATE_TYPE_POWER_DOWN, + }; + + if (psci_ops.cpu_off) + psci_ops.cpu_off(ps); + + /* We should never return */ + panic("psci: cpu %d failed to shutdown\n", cpu); +} +#else +#define psci_cpu_die NULL +#endif + +bool __init psci_smp_available(void) +{ + /* is cpu_on available at least? */ + return (psci_ops.cpu_on != NULL); +} + +struct smp_operations __initdata psci_smp_ops = { + .smp_boot_secondary = psci_boot_secondary, + .cpu_die = psci_cpu_die, +}; -- cgit v1.2.3 From fdeb94b5dc5bf9db7b3e36f3f38089a554f6a108 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Mon, 3 Jun 2013 23:09:14 +0100 Subject: ARM: 7745/1: psci: fix building without HOTPLUG_CPU The cpu_die field in smp_operations is not valid with CONFIG_HOTPLUG_CPU, so we must enclose it in #ifdef, but at least that lets us remove two other lines. Signed-off-by: Arnd Bergmann Cc: Stefano Stabellini Cc: Will Deacon Signed-off-by: Russell King --- arch/arm/kernel/psci_smp.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/arm/kernel/psci_smp.c') diff --git a/arch/arm/kernel/psci_smp.c b/arch/arm/kernel/psci_smp.c index 23a11424c568..219f1d73572a 100644 --- a/arch/arm/kernel/psci_smp.c +++ b/arch/arm/kernel/psci_smp.c @@ -68,8 +68,6 @@ void __ref psci_cpu_die(unsigned int cpu) /* We should never return */ panic("psci: cpu %d failed to shutdown\n", cpu); } -#else -#define psci_cpu_die NULL #endif bool __init psci_smp_available(void) @@ -80,5 +78,7 @@ bool __init psci_smp_available(void) struct smp_operations __initdata psci_smp_ops = { .smp_boot_secondary = psci_boot_secondary, +#ifdef CONFIG_HOTPLUG_CPU .cpu_die = psci_cpu_die, +#endif }; -- cgit v1.2.3 From 8bd26e3a7e49af2697449bbcb7187a39dc85d672 Mon Sep 17 00:00:00 2001 From: Paul Gortmaker Date: Mon, 17 Jun 2013 15:43:14 -0400 Subject: arm: delete __cpuinit/__CPUINIT usage from all ARM users The __cpuinit type of throwaway sections might have made sense some time ago when RAM was more constrained, but now the savings do not offset the cost and complications. For example, the fix in commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time") is a good example of the nasty type of bugs that can be created with improper use of the various __init prefixes. After a discussion on LKML[1] it was decided that cpuinit should go the way of devinit and be phased out. Once all the users are gone, we can then finally remove the macros themselves from linux/init.h. Note that some harmless section mismatch warnings may result, since notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c) and are flagged as __cpuinit -- so if we remove the __cpuinit from the arch specific callers, we will also get section mismatch warnings. As an intermediate step, we intend to turn the linux/init.h cpuinit related content into no-ops as early as possible, since that will get rid of these warnings. In any case, they are temporary and harmless. This removes all the ARM uses of the __cpuinit macros from C code, and all __CPUINIT from assembly code. It also had two ".previous" section statements that were paired off against __CPUINIT (aka .section ".cpuinit.text") that also get removed here. [1] https://lkml.org/lkml/2013/5/20/589 Cc: Russell King Cc: Will Deacon Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Paul Gortmaker --- arch/arm/kernel/psci_smp.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'arch/arm/kernel/psci_smp.c') diff --git a/arch/arm/kernel/psci_smp.c b/arch/arm/kernel/psci_smp.c index 219f1d73572a..70ded3fb42d9 100644 --- a/arch/arm/kernel/psci_smp.c +++ b/arch/arm/kernel/psci_smp.c @@ -46,8 +46,7 @@ extern void secondary_startup(void); -static int __cpuinit psci_boot_secondary(unsigned int cpu, - struct task_struct *idle) +static int psci_boot_secondary(unsigned int cpu, struct task_struct *idle) { if (psci_ops.cpu_on) return psci_ops.cpu_on(cpu_logical_map(cpu), -- cgit v1.2.3