diff options
Diffstat (limited to 'arch/arm/mach-versatile/platsmp-vexpress.c')
-rw-r--r-- | arch/arm/mach-versatile/platsmp-vexpress.c | 93 |
1 files changed, 93 insertions, 0 deletions
diff --git a/arch/arm/mach-versatile/platsmp-vexpress.c b/arch/arm/mach-versatile/platsmp-vexpress.c new file mode 100644 index 000000000..1ee3c45e7 --- /dev/null +++ b/arch/arm/mach-versatile/platsmp-vexpress.c @@ -0,0 +1,93 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2002 ARM Ltd. + * All Rights Reserved + */ +#include <linux/init.h> +#include <linux/errno.h> +#include <linux/smp.h> +#include <linux/io.h> +#include <linux/of_address.h> +#include <linux/vexpress.h> + +#include <asm/mcpm.h> +#include <asm/smp_scu.h> +#include <asm/mach/map.h> + +#include "platsmp.h" +#include "vexpress.h" + +bool __init vexpress_smp_init_ops(void) +{ +#ifdef CONFIG_MCPM + int cpu; + struct device_node *cpu_node, *cci_node; + + /* + * The best way to detect a multi-cluster configuration + * is to detect if the kernel can take over CCI ports + * control. Loop over possible CPUs and check if CCI + * port control is available. + * Override the default vexpress_smp_ops if so. + */ + for_each_possible_cpu(cpu) { + bool available; + + cpu_node = of_get_cpu_node(cpu, NULL); + if (WARN(!cpu_node, "Missing cpu device node!")) + return false; + + cci_node = of_parse_phandle(cpu_node, "cci-control-port", 0); + available = cci_node && of_device_is_available(cci_node); + of_node_put(cci_node); + of_node_put(cpu_node); + + if (!available) + return false; + } + + mcpm_smp_set_ops(); + return true; +#else + return false; +#endif +} + +static const struct of_device_id vexpress_smp_dt_scu_match[] __initconst = { + { .compatible = "arm,cortex-a5-scu", }, + { .compatible = "arm,cortex-a9-scu", }, + {} +}; + +static void __init vexpress_smp_dt_prepare_cpus(unsigned int max_cpus) +{ + struct device_node *scu = of_find_matching_node(NULL, + vexpress_smp_dt_scu_match); + + if (scu) + scu_enable(of_iomap(scu, 0)); + + /* + * Write the address of secondary startup into the + * system-wide flags register. The boot monitor waits + * until it receives a soft interrupt, and then the + * secondary CPU branches to this address. + */ + vexpress_flags_set(__pa_symbol(versatile_secondary_startup)); +} + +#ifdef CONFIG_HOTPLUG_CPU +static void vexpress_cpu_die(unsigned int cpu) +{ + versatile_immitation_cpu_die(cpu, 0x40); +} +#endif + +const struct smp_operations vexpress_smp_dt_ops __initconst = { + .smp_prepare_cpus = vexpress_smp_dt_prepare_cpus, + .smp_secondary_init = versatile_secondary_init, + .smp_boot_secondary = versatile_boot_secondary, +#ifdef CONFIG_HOTPLUG_CPU + .cpu_die = vexpress_cpu_die, +#endif +}; |