diff options
Diffstat (limited to 'arch/arm/kernel/devtree.c')
| -rw-r--r-- | arch/arm/kernel/devtree.c | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/arch/arm/kernel/devtree.c b/arch/arm/kernel/devtree.c index bee7f9d47f0..a4662b1c3fd 100644 --- a/arch/arm/kernel/devtree.c +++ b/arch/arm/kernel/devtree.c @@ -19,8 +19,10 @@ #include <linux/of_irq.h> #include <linux/of_platform.h> +#include <asm/cputype.h> #include <asm/setup.h> #include <asm/page.h> +#include <asm/smp_plat.h> #include <asm/mach/arch.h> #include <asm/mach-types.h> @@ -61,6 +63,44 @@ void __init arm_dt_memblock_reserve(void) } } +/* + * arm_dt_init_cpu_maps - Function retrieves cpu nodes from the device tree + * and builds the cpu logical map array containing MPIDR values related to + * logical cpus + * + * Updates the cpu possible mask with the number of parsed cpu nodes + */ +void __init arm_dt_init_cpu_maps(void) +{ + struct device_node *dn = NULL; + int i, cpu = 1; + + while ((dn = of_find_node_by_type(dn, "cpu")) && cpu <= nr_cpu_ids) { + const u32 *hwid; + int len; + + pr_debug(" * %s...\n", dn->full_name); + + hwid = of_get_property(dn, "reg", &len); + + if (!hwid || len != 4) { + pr_err(" * %s missing reg property\n", dn->full_name); + continue; + } + + i = (be32_to_cpup(hwid) == (read_cpuid_mpidr() & 0xffffff)) + ? 0 : cpu++; + + if (!i) + printk(KERN_INFO "Booting Linux on CPU HWID 0x%x\n", + be32_to_cpup(hwid)); + + cpu_logical_map(i) = be32_to_cpup(hwid); + + set_cpu_possible(i, true); + } +} + /** * setup_machine_fdt - Machine setup when an dtb was passed to the kernel * @dt_phys: physical address of dt blob |