Commit a7b3d5a7 authored by Jisheng Zhang's avatar Jisheng Zhang Committed by Sebastian Hesselbarth

arm: berlin: add CPU hotplug support

Add cpu hotplug support for berlin SoCs such as BG2 and BG2Q. These SoC
don't support power off cpu independently, but we also want cpu hotplug
support in these SoCs. We achieve this goal by putting the dying CPU in
WFI state after the coherency is disabled, then asserting the dying CPU
reset bit to put the CPU in reset state.
Signed-off-by: default avatarJisheng Zhang <jszhang@marvell.com>
Signed-off-by: default avatarSebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
parent ac7fc233
...@@ -14,6 +14,7 @@ ...@@ -14,6 +14,7 @@
#include <linux/of_address.h> #include <linux/of_address.h>
#include <asm/cacheflush.h> #include <asm/cacheflush.h>
#include <asm/cp15.h>
#include <asm/smp_plat.h> #include <asm/smp_plat.h>
#include <asm/smp_scu.h> #include <asm/smp_scu.h>
...@@ -98,8 +99,32 @@ static void __init berlin_smp_prepare_cpus(unsigned int max_cpus) ...@@ -98,8 +99,32 @@ static void __init berlin_smp_prepare_cpus(unsigned int max_cpus)
iounmap(scu_base); iounmap(scu_base);
} }
#ifdef CONFIG_HOTPLUG_CPU
static void berlin_cpu_die(unsigned int cpu)
{
v7_exit_coherency_flush(louis);
while (1)
cpu_do_idle();
}
static int berlin_cpu_kill(unsigned int cpu)
{
u32 val;
val = readl(cpu_ctrl + CPU_RESET_NON_SC);
val &= ~BIT(cpu_logical_map(cpu));
writel(val, cpu_ctrl + CPU_RESET_NON_SC);
return 1;
}
#endif
static struct smp_operations berlin_smp_ops __initdata = { static struct smp_operations berlin_smp_ops __initdata = {
.smp_prepare_cpus = berlin_smp_prepare_cpus, .smp_prepare_cpus = berlin_smp_prepare_cpus,
.smp_boot_secondary = berlin_boot_secondary, .smp_boot_secondary = berlin_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
.cpu_die = berlin_cpu_die,
.cpu_kill = berlin_cpu_kill,
#endif
}; };
CPU_METHOD_OF_DECLARE(berlin_smp, "marvell,berlin-smp", &berlin_smp_ops); CPU_METHOD_OF_DECLARE(berlin_smp, "marvell,berlin-smp", &berlin_smp_ops);
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