diff options
| -rw-r--r-- | arch/arm64/include/asm/cputype.h | 2 | ||||
| -rw-r--r-- | arch/arm64/include/asm/smp_plat.h | 30 | ||||
| -rw-r--r-- | arch/arm64/kernel/setup.c | 4 | ||||
| -rw-r--r-- | arch/arm64/kernel/smp.c | 92 |
4 files changed, 121 insertions, 7 deletions
diff --git a/arch/arm64/include/asm/cputype.h b/arch/arm64/include/asm/cputype.h index 9397a17bec0..3780b2e7f88 100644 --- a/arch/arm64/include/asm/cputype.h +++ b/arch/arm64/include/asm/cputype.h @@ -28,6 +28,8 @@ #define INVALID_HWID ULONG_MAX +#define MPIDR_HWID_BITMASK 0xff00ffffff + #define read_cpuid(reg) ({ \ u64 __val; \ asm("mrs %0, " reg : "=r" (__val)); \ diff --git a/arch/arm64/include/asm/smp_plat.h b/arch/arm64/include/asm/smp_plat.h new file mode 100644 index 00000000000..ed43a0d2b1b --- /dev/null +++ b/arch/arm64/include/asm/smp_plat.h @@ -0,0 +1,30 @@ +/* + * Definitions specific to SMP platforms. + * + * Copyright (C) 2013 ARM Ltd. + * + * 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/>. + */ + +#ifndef __ASM_SMP_PLAT_H +#define __ASM_SMP_PLAT_H + +#include <asm/types.h> + +/* + * Logical CPU mapping. + */ +extern u64 __cpu_logical_map[NR_CPUS]; +#define cpu_logical_map(cpu) __cpu_logical_map[cpu] + +#endif /* __ASM_SMP_PLAT_H */ diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index 9c023d714f4..6a9a5329259 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -47,6 +47,7 @@ #include <asm/cputable.h> #include <asm/sections.h> #include <asm/setup.h> +#include <asm/smp_plat.h> #include <asm/cacheflush.h> #include <asm/tlbflush.h> #include <asm/traps.h> @@ -241,6 +242,8 @@ static void __init request_standard_resources(void) } } +u64 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID_HWID }; + void __init setup_arch(char **cmdline_p) { setup_processor(); @@ -265,6 +268,7 @@ void __init setup_arch(char **cmdline_p) psci_init(); + cpu_logical_map(0) = read_cpuid_mpidr() & MPIDR_HWID_BITMASK; #ifdef CONFIG_SMP smp_init_cpus(); #endif diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index a57a373d305..d4dcc651525 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -43,6 +43,7 @@ #include <asm/pgtable.h> #include <asm/pgalloc.h> #include <asm/processor.h> +#include <asm/smp_plat.h> #include <asm/sections.h> #include <asm/tlbflush.h> #include <asm/ptrace.h> @@ -96,7 +97,7 @@ static int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle) /* * Update the pen release flag. */ - write_pen_release(cpu); + write_pen_release(cpu_logical_map(cpu)); /* * Send an event, causing the secondaries to read pen_release. @@ -257,15 +258,77 @@ static const struct smp_enable_ops * __init smp_get_enable_ops(const char *name) } /* - * Enumerate the possible CPU set from the device tree. + * Enumerate the possible CPU set from the device tree and build the + * cpu logical map array containing MPIDR values related to logical + * cpus. Assumes that cpu_logical_map(0) has already been initialized. */ void __init smp_init_cpus(void) { const char *enable_method; struct device_node *dn = NULL; - int cpu = 0; + int i, cpu = 1; + bool bootcpu_valid = false; while ((dn = of_find_node_by_type(dn, "cpu"))) { + u64 hwid; + + /* + * A cpu node with missing "reg" property is + * considered invalid to build a cpu_logical_map + * entry. + */ + if (of_property_read_u64(dn, "reg", &hwid)) { + pr_err("%s: missing reg property\n", dn->full_name); + goto next; + } + + /* + * Non affinity bits must be set to 0 in the DT + */ + if (hwid & ~MPIDR_HWID_BITMASK) { + pr_err("%s: invalid reg property\n", dn->full_name); + goto next; + } + + /* + * Duplicate MPIDRs are a recipe for disaster. Scan + * all initialized entries and check for + * duplicates. If any is found just ignore the cpu. + * cpu_logical_map was initialized to INVALID_HWID to + * avoid matching valid MPIDR values. + */ + for (i = 1; (i < cpu) && (i < NR_CPUS); i++) { + if (cpu_logical_map(i) == hwid) { + pr_err("%s: duplicate cpu reg properties in the DT\n", + dn->full_name); + goto next; + } + } + + /* + * The numbering scheme requires that the boot CPU + * must be assigned logical id 0. Record it so that + * the logical map built from DT is validated and can + * be used. + */ + if (hwid == cpu_logical_map(0)) { + if (bootcpu_valid) { + pr_err("%s: duplicate boot cpu reg property in DT\n", + dn->full_name); + goto next; + } + + bootcpu_valid = true; + + /* + * cpu_logical_map has already been + * initialized and the boot cpu doesn't need + * the enable-method so continue without + * incrementing cpu. + */ + continue; + } + if (cpu >= NR_CPUS) goto next; @@ -274,22 +337,24 @@ void __init smp_init_cpus(void) */ enable_method = of_get_property(dn, "enable-method", NULL); if (!enable_method) { - pr_err("CPU %d: missing enable-method property\n", cpu); + pr_err("%s: missing enable-method property\n", + dn->full_name); goto next; } smp_enable_ops[cpu] = smp_get_enable_ops(enable_method); if (!smp_enable_ops[cpu]) { - pr_err("CPU %d: invalid enable-method property: %s\n", - cpu, enable_method); + pr_err("%s: invalid enable-method property: %s\n", + dn->full_name, enable_method); goto next; } if (smp_enable_ops[cpu]->init_cpu(dn, cpu)) goto next; - set_cpu_possible(cpu, true); + pr_debug("cpu logical map 0x%llx\n", hwid); + cpu_logical_map(cpu) = hwid; next: cpu++; } @@ -298,6 +363,19 @@ next: if (cpu > NR_CPUS) pr_warning("no. of cores (%d) greater than configured maximum of %d - clipping\n", cpu, NR_CPUS); + + if (!bootcpu_valid) { + pr_err("DT missing boot CPU MPIDR, not enabling secondaries\n"); + return; + } + + /* + * All the cpus that made it to the cpu_logical_map have been + * validated so set them as possible cpus. + */ + for (i = 0; i < NR_CPUS; i++) + if (cpu_logical_map(i) != INVALID_HWID) + set_cpu_possible(i, true); } void __init smp_prepare_cpus(unsigned int max_cpus) |