[PATCH v2 6/6] [RFC] arm: use PSCI if available
Stefano Stabellini
stefano.stabellini at eu.citrix.com
Tue Mar 26 10:41:15 EDT 2013
Check for the presence of PSCI before setting smp_ops, use PSCI if it is
available.
This is useful because at least when running on Xen it's possible to have a
PSCI node for example on a Versatile Express or an Exynos5 machine. In these
cases the PSCI SMP calls should be the ones to be called.
Remove virt_smp_ops and platsmp.c from mach-virt because they aren't needed
anymore.
Signed-off-by: Stefano Stabellini <stefano.stabellini at eu.citrix.com>
CC: will.deacon at arm.com
CC: arnd at arndb.de
CC: marc.zyngier at arm.com
CC: linux at arm.linux.org.uk
CC: nico at linaro.org
---
arch/arm/include/asm/psci.h | 1 +
arch/arm/kernel/psci.c | 42 +++++++++++++++++++++++++++---
arch/arm/kernel/smp.c | 7 ++++-
arch/arm/mach-virt/Makefile | 1 -
arch/arm/mach-virt/platsmp.c | 58 ------------------------------------------
arch/arm/mach-virt/virt.c | 3 --
6 files changed, 45 insertions(+), 67 deletions(-)
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..e64ea84 100644
--- a/arch/arm/include/asm/psci.h
+++ b/arch/arm/include/asm/psci.h
@@ -32,5 +32,6 @@ struct psci_operations {
};
extern struct psci_operations psci_ops;
+int psci_init(struct smp_operations *ops);
#endif /* __ASM_ARM_PSCI_H */
diff --git a/arch/arm/kernel/psci.c b/arch/arm/kernel/psci.c
index 3653164..6f66d93 100644
--- a/arch/arm/kernel/psci.c
+++ b/arch/arm/kernel/psci.c
@@ -16,6 +16,7 @@
#define pr_fmt(fmt) "psci: " fmt
#include <linux/init.h>
+#include <linux/irqchip/arm-gic.h>
#include <linux/of.h>
#include <asm/compiler.h>
@@ -23,7 +24,9 @@
#include <asm/opcodes-sec.h>
#include <asm/opcodes-virt.h>
#include <asm/psci.h>
+#include <asm/smp_plat.h>
+extern void secondary_startup(void);
struct psci_operations psci_ops;
static int (*invoke_psci_fn)(u32, u32, u32, u32);
@@ -153,20 +156,50 @@ static int psci_migrate(unsigned long cpuid)
return psci_to_linux_errno(err);
}
+static void __init psci_smp_init_cpus(void)
+{
+}
+
+static void __init psci_smp_prepare_cpus(unsigned int max_cpus)
+{
+}
+
+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);
+}
+
+struct smp_operations __initdata psci_smp_ops = {
+ .smp_init_cpus = psci_smp_init_cpus,
+ .smp_prepare_cpus = psci_smp_prepare_cpus,
+ .smp_secondary_init = psci_secondary_init,
+ .smp_boot_secondary = psci_boot_secondary,
+};
+
static const struct of_device_id psci_of_match[] __initconst = {
{ .compatible = "arm,psci", },
{},
};
-static int __init psci_init(void)
+int __init psci_init(struct smp_operations *ops)
{
struct device_node *np;
const char *method;
u32 id;
+ int rc = -EINVAL;
np = of_find_matching_node(NULL, psci_of_match);
if (!np)
- return 0;
+ return -ENODEV;
pr_info("probing function IDs from device-tree\n");
@@ -203,9 +236,10 @@ static int __init psci_init(void)
psci_function_id[PSCI_FN_MIGRATE] = id;
psci_ops.migrate = psci_migrate;
}
+ *ops = psci_smp_ops;
+ rc = 0;
out_put_node:
of_node_put(np);
- return 0;
+ return rc;
}
-early_initcall(psci_init);
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index 31644f1..09eda3c 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -38,6 +38,7 @@
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/processor.h>
+#include <asm/psci.h>
#include <asm/sections.h>
#include <asm/tlbflush.h>
#include <asm/ptrace.h>
@@ -74,7 +75,11 @@ static struct smp_operations smp_ops;
void __init smp_set_ops(struct smp_operations *ops)
{
- if (ops)
+ int rc = -ENODEV;
+#ifdef CONFIG_ARM_PSCI
+ rc = psci_init(&smp_ops);
+#endif
+ if (rc && ops)
smp_ops = *ops;
};
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 at arm.com>
- *
- * 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 528c05e..c417752 100644
--- a/arch/arm/mach-virt/virt.c
+++ b/arch/arm/mach-virt/virt.c
@@ -44,12 +44,9 @@ 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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