diff options
Diffstat (limited to 'arch/arm/mach-vexpress/platsmp.c')
-rw-r--r-- | arch/arm/mach-vexpress/platsmp.c | 155 |
1 files changed, 153 insertions, 2 deletions
diff --git a/arch/arm/mach-vexpress/platsmp.c b/arch/arm/mach-vexpress/platsmp.c index a1ed6d68597..14ba1128ae8 100644 --- a/arch/arm/mach-vexpress/platsmp.c +++ b/arch/arm/mach-vexpress/platsmp.c @@ -12,6 +12,11 @@ #include <linux/errno.h> #include <linux/smp.h> #include <linux/io.h> +#include <linux/of_fdt.h> + +#include <asm/smp_scu.h> +#include <asm/hardware/gic.h> +#include <asm/mach/map.h> #include <mach/motherboard.h> @@ -19,13 +24,156 @@ extern void versatile_secondary_startup(void); +#if defined(CONFIG_OF) + +static enum { + GENERIC_SCU, + CORTEX_A9_SCU, +} vexpress_dt_scu __initdata = GENERIC_SCU; + +static struct map_desc vexpress_dt_cortex_a9_scu_map __initdata = { + .virtual = V2T_PERIPH, + /* .pfn set in vexpress_dt_init_cortex_a9_scu() */ + .length = SZ_128, + .type = MT_DEVICE, +}; + +static void *vexpress_dt_cortex_a9_scu_base __initdata; + +const static char *vexpress_dt_cortex_a9_match[] __initconst = { + "arm,cortex-a5-scu", + "arm,cortex-a9-scu", + NULL +}; + +static int __init vexpress_dt_find_scu(unsigned long node, + const char *uname, int depth, void *data) +{ + if (of_flat_dt_match(node, vexpress_dt_cortex_a9_match)) { + phys_addr_t phys_addr; + __be32 *reg = of_get_flat_dt_prop(node, "reg", NULL); + + if (WARN_ON(!reg)) + return -EINVAL; + + phys_addr = be32_to_cpup(reg); + vexpress_dt_scu = CORTEX_A9_SCU; + + vexpress_dt_cortex_a9_scu_map.pfn = __phys_to_pfn(phys_addr); + iotable_init(&vexpress_dt_cortex_a9_scu_map, 1); + vexpress_dt_cortex_a9_scu_base = ioremap(phys_addr, SZ_256); + if (WARN_ON(!vexpress_dt_cortex_a9_scu_base)) + return -EFAULT; + } + + return 0; +} + +void __init vexpress_dt_smp_map_io(void) +{ + if (initial_boot_params) + WARN_ON(of_scan_flat_dt(vexpress_dt_find_scu, NULL)); +} + +static int __init vexpress_dt_cpus_num(unsigned long node, const char *uname, + int depth, void *data) +{ + static int prev_depth = -1; + static int nr_cpus = -1; + + if (prev_depth > depth && nr_cpus > 0) + return nr_cpus; + + if (nr_cpus < 0 && strcmp(uname, "cpus") == 0) + nr_cpus = 0; + + if (nr_cpus >= 0) { + const char *device_type = of_get_flat_dt_prop(node, + "device_type", NULL); + + if (device_type && strcmp(device_type, "cpu") == 0) + nr_cpus++; + } + + prev_depth = depth; + + return 0; +} + +static void __init vexpress_dt_smp_init_cpus(void) +{ + int ncores = 0, i; + + switch (vexpress_dt_scu) { + case GENERIC_SCU: + ncores = of_scan_flat_dt(vexpress_dt_cpus_num, NULL); + break; + case CORTEX_A9_SCU: + ncores = scu_get_core_count(vexpress_dt_cortex_a9_scu_base); + break; + default: + WARN_ON(1); + break; + } + + if (ncores < 2) + return; + + if (ncores > nr_cpu_ids) { + pr_warn("SMP: %u cores greater than maximum (%u), clipping\n", + ncores, nr_cpu_ids); + ncores = nr_cpu_ids; + } + + for (i = 0; i < ncores; ++i) + set_cpu_possible(i, true); + + set_smp_cross_call(gic_raise_softirq); +} + +static void __init vexpress_dt_smp_prepare_cpus(unsigned int max_cpus) +{ + int i; + + switch (vexpress_dt_scu) { + case GENERIC_SCU: + for (i = 0; i < max_cpus; i++) + set_cpu_present(i, true); + break; + case CORTEX_A9_SCU: + scu_enable(vexpress_dt_cortex_a9_scu_base); + break; + default: + WARN_ON(1); + break; + } +} + +#else + +static void __init vexpress_dt_smp_init_cpus(void) +{ + WARN_ON(1); +} + +void __init vexpress_dt_smp_prepare_cpus(unsigned int max_cpus) +{ + WARN_ON(1); +} + +#endif + /* * Initialise the CPU possible map early - this describes the CPUs * which may be present or become present in the system. */ void __init smp_init_cpus(void) { - ct_desc->init_cpu_map(); + if (ct_desc) + ct_desc->init_cpu_map(); + else + vexpress_dt_smp_init_cpus(); + } void __init platform_smp_prepare_cpus(unsigned int max_cpus) @@ -34,7 +182,10 @@ void __init platform_smp_prepare_cpus(unsigned int max_cpus) * Initialise the present map, which describes the set of CPUs * actually populated at the present time. */ - ct_desc->smp_enable(max_cpus); + if (ct_desc) + ct_desc->smp_enable(max_cpus); + else + vexpress_dt_smp_prepare_cpus(max_cpus); /* * Write the address of secondary startup into the |