ARM64: kernel: make cpu_ops hooks DT agnostic

[firefly-linux-kernel-4.4.55.git] / arch / arm64 / kernel / smp.c

diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index 2cb008177252f08d876875e08e4448b5b3260dde..98eb68b5660fa9cc57eee587f2c169cf2dcc1d8c 100644 (file)
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -318,6 +318,23 @@ void __init smp_prepare_boot_cpu(void)
        set_my_cpu_offset(per_cpu_offset(smp_processor_id()));
 }
 
+/*
+ * Initialize cpu operations for a logical cpu and
+ * set it in the possible mask on success
+ */
+static int __init smp_cpu_setup(int cpu)
+{
+       if (cpu_read_ops(cpu))
+               return -ENODEV;
+
+       if (cpu_ops[cpu]->cpu_init(cpu))
+               return -ENODEV;
+
+       set_cpu_possible(cpu, true);
+
+       return 0;
+}
+
 /*
  * Enumerate the possible CPU set from the device tree and build the
  * cpu logical map array containing MPIDR values related to logical
@@ -395,12 +412,6 @@ void __init of_smp_init_cpus(void)
                if (cpu >= NR_CPUS)
                        goto next;
 
-               if (cpu_read_ops(dn, cpu) != 0)
-                       goto next;
-
-               if (cpu_ops[cpu]->cpu_init(dn, cpu))
-                       goto next;
-
                pr_debug("cpu logical map 0x%llx\n", hwid);
                cpu_logical_map(cpu) = hwid;
 next:
@@ -418,12 +429,18 @@ next:
        }
 
        /*
-        * All the cpus that made it to the cpu_logical_map have been
-        * validated so set them as possible cpus.
+        * We need to set the cpu_logical_map entries before enabling
+        * the cpus so that cpu processor description entries (DT cpu nodes
+        * and ACPI MADT entries) can be retrieved by matching the cpu hwid
+        * with entries in cpu_logical_map while initializing the cpus.
+        * If the cpu set-up fails, invalidate the cpu_logical_map entry.
         */
-       for (i = 0; i < NR_CPUS; i++)
-               if (cpu_logical_map(i) != INVALID_HWID)
-                       set_cpu_possible(i, true);
+       for (i = 1; i < NR_CPUS; i++) {
+               if (cpu_logical_map(i) != INVALID_HWID) {
+                       if (smp_cpu_setup(i))
+                               cpu_logical_map(i) = INVALID_HWID;
+               }
+       }
 }
 
 void __init smp_prepare_cpus(unsigned int max_cpus)