[PATCH v8 1/2] arm: introduce psci_smp_ops
From: Stefano Stabellini
Date: Wed Apr 24 2013 - 14:40:36 EST
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.
Use psci_smp_ops if the platform doesn't provide its own smp_ops.
If PSCI is available on the platform, prefer psci_smp_ops over the
platform smp_ops.
Changes in v8:
- merge "prefer psci_smp_ops over mdesc->smp" into this patch.
Changes in v6:
- fixed return values for psci_smp_available and psci_init ifndef
CONFIG_ARM_PSCI.
Changes in v5:
- document psci_operations;
- psci_init returns NULL.
Signed-off-by: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>
---
arch/arm/include/asm/psci.h | 29 ++++++++++++++++++
arch/arm/kernel/Makefile | 5 ++-
arch/arm/kernel/psci.c | 7 ++--
arch/arm/kernel/psci_smp.c | 67 ++++++++++++++++++++++++++++++++++++++++++
arch/arm/kernel/setup.c | 7 ++++-
arch/arm/mach-virt/Makefile | 1 -
arch/arm/mach-virt/platsmp.c | 58 ------------------------------------
arch/arm/mach-virt/virt.c | 3 --
8 files changed, 109 insertions(+), 68 deletions(-)
create mode 100644 arch/arm/kernel/psci_smp.c
delete mode 100644 arch/arm/mach-virt/platsmp.c
diff --git a/arch/arm/include/asm/psci.h b/arch/arm/include/asm/psci.h
index ce0dbe7..fa44417 100644
--- a/arch/arm/include/asm/psci.h
+++ b/arch/arm/include/asm/psci.h
@@ -23,6 +23,26 @@ struct psci_power_state {
u8 affinity_level;
};
+/*
+ * 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
+ *
+ */
struct psci_operations {
int (*cpu_suspend)(struct psci_power_state state,
unsigned long entry_point);
@@ -32,5 +52,14 @@ struct psci_operations {
};
extern struct psci_operations psci_ops;
+extern struct smp_operations psci_smp_ops;
+
+#ifdef CONFIG_ARM_PSCI
+void psci_init(void);
+bool psci_smp_available(void);
+#else
+static inline void psci_init(void) { }
+static inline bool psci_smp_available(void) { return false; }
+#endif
#endif /* __ASM_ARM_PSCI_H */
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
index 5f3338e..dd9d90a 100644
--- a/arch/arm/kernel/Makefile
+++ b/arch/arm/kernel/Makefile
@@ -82,6 +82,9 @@ obj-$(CONFIG_DEBUG_LL) += debug.o
obj-$(CONFIG_EARLY_PRINTK) += early_printk.o
obj-$(CONFIG_ARM_VIRT_EXT) += hyp-stub.o
-obj-$(CONFIG_ARM_PSCI) += psci.o
+ifeq ($(CONFIG_ARM_PSCI),y)
+obj-y += psci.o
+obj-$(CONFIG_SMP) += psci_smp.o
+endif
extra-y := $(head-y) vmlinux.lds
diff --git a/arch/arm/kernel/psci.c b/arch/arm/kernel/psci.c
index 3653164..4693188 100644
--- a/arch/arm/kernel/psci.c
+++ b/arch/arm/kernel/psci.c
@@ -158,7 +158,7 @@ static const struct of_device_id psci_of_match[] __initconst = {
{},
};
-static int __init psci_init(void)
+void __init psci_init(void)
{
struct device_node *np;
const char *method;
@@ -166,7 +166,7 @@ static int __init psci_init(void)
np = of_find_matching_node(NULL, psci_of_match);
if (!np)
- return 0;
+ return;
pr_info("probing function IDs from device-tree\n");
@@ -206,6 +206,5 @@ static int __init psci_init(void)
out_put_node:
of_node_put(np);
- return 0;
+ return;
}
-early_initcall(psci_init);
diff --git a/arch/arm/kernel/psci_smp.c b/arch/arm/kernel/psci_smp.c
new file mode 100644
index 0000000..66b0f77
--- /dev/null
+++ b/arch/arm/kernel/psci_smp.c
@@ -0,0 +1,67 @@
+/*
+ * 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 <will.deacon@xxxxxxx>
+ */
+
+#include <linux/init.h>
+#include <linux/irqchip/arm-gic.h>
+#include <linux/smp.h>
+#include <linux/of.h>
+
+#include <asm/psci.h>
+#include <asm/smp_plat.h>
+
+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;
+}
+
+static void __cpuinit psci_secondary_init(unsigned int cpu)
+{
+ gic_secondary_init(0);
+}
+
+#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_secondary_init = psci_secondary_init,
+ .smp_boot_secondary = psci_boot_secondary,
+ .cpu_die = psci_cpu_die,
+};
diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index 3f6cbb2..dad3048 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -36,6 +36,7 @@
#include <asm/cputype.h>
#include <asm/elf.h>
#include <asm/procinfo.h>
+#include <asm/psci.h>
#include <asm/sections.h>
#include <asm/setup.h>
#include <asm/smp_plat.h>
@@ -766,9 +767,13 @@ void __init setup_arch(char **cmdline_p)
unflatten_device_tree();
arm_dt_init_cpu_maps();
+ psci_init();
#ifdef CONFIG_SMP
if (is_smp()) {
- smp_set_ops(mdesc->smp);
+ if (psci_smp_available())
+ smp_set_ops(&psci_smp_ops);
+ else if (mdesc->smp)
+ smp_set_ops(mdesc->smp);
smp_init_cpus();
}
#endif
diff --git a/arch/arm/mach-virt/Makefile b/arch/arm/mach-virt/Makefile
index 042afc1..7ddbfa6 100644
--- a/arch/arm/mach-virt/Makefile
+++ b/arch/arm/mach-virt/Makefile
@@ -3,4 +3,3 @@
#
obj-y := virt.o
-obj-$(CONFIG_SMP) += platsmp.o
diff --git a/arch/arm/mach-virt/platsmp.c b/arch/arm/mach-virt/platsmp.c
deleted file mode 100644
index 8badaab..0000000
--- a/arch/arm/mach-virt/platsmp.c
+++ /dev/null
@@ -1,58 +0,0 @@
-/*
- * Dummy Virtual Machine - does what it says on the tin.
- *
- * Copyright (C) 2012 ARM Ltd
- * Author: Will Deacon <will.deacon@xxxxxxx>
- *
- * 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.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- */
-
-#include <linux/init.h>
-#include <linux/smp.h>
-#include <linux/of.h>
-
-#include <linux/irqchip/arm-gic.h>
-
-#include <asm/psci.h>
-#include <asm/smp_plat.h>
-
-extern void secondary_startup(void);
-
-static void __init virt_smp_init_cpus(void)
-{
-}
-
-static void __init virt_smp_prepare_cpus(unsigned int max_cpus)
-{
-}
-
-static int __cpuinit virt_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;
-}
-
-static void __cpuinit virt_secondary_init(unsigned int cpu)
-{
- gic_secondary_init(0);
-}
-
-struct smp_operations __initdata virt_smp_ops = {
- .smp_init_cpus = virt_smp_init_cpus,
- .smp_prepare_cpus = virt_smp_prepare_cpus,
- .smp_secondary_init = virt_secondary_init,
- .smp_boot_secondary = virt_boot_secondary,
-};
diff --git a/arch/arm/mach-virt/virt.c b/arch/arm/mach-virt/virt.c
index 31666f6..4438ed0 100644
--- a/arch/arm/mach-virt/virt.c
+++ b/arch/arm/mach-virt/virt.c
@@ -43,12 +43,9 @@ static const char *virt_dt_match[] = {
NULL
};
-extern struct smp_operations virt_smp_ops;
-
DT_MACHINE_START(VIRT, "Dummy Virtual Machine")
.init_irq = irqchip_init,
.init_time = virt_timer_init,
.init_machine = virt_init,
- .smp = smp_ops(virt_smp_ops),
.dt_compat = virt_dt_match,
MACHINE_END
--
1.7.2.5
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