ARM64: simplify cpu_read_bootcpu_ops using OF/DT helper

Once the cpu_logical_map for any logical cpu is populated with the
corresponding physical identifier(i.e. mpidr), it's device node can
be retrieved using the DT helper 'of_get_cpu_node'. Currently the
device tree parsing code to get boot cpu node is duplicated in
'cpu_read_bootcpu_ops'.

This patch replaces the code parsing the device tree for the boot
cpu with of_get_cpu_node.

Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

1 files changed, 5 insertions, 17 deletions

diff --git a/arch/arm64/kernel/cpu_ops.c b/arch/arm64/kernel/cpu_ops.c
index aa0c9e78dbe1..e2ba274612cf 100644
--- a/arch/arm64/kernel/cpu_ops.c
+++ b/arch/arm64/kernel/cpu_ops.c
@@ -78,22 +78,10 @@ int __init cpu_read_ops(struct device_node *dn, int cpu)
 
 void __init cpu_read_bootcpu_ops(void)
 {
-        struct device_node *dn = NULL;
-        u64 mpidr = cpu_logical_map(0);
-
-        while ((dn = of_find_node_by_type(dn, "cpu"))) {
-                u64 hwid;
-                const __be32 *prop;
-
-                prop = of_get_property(dn, "reg", NULL);
-                if (!prop)
-                        continue;
-
-                hwid = of_read_number(prop, of_n_addr_cells(dn));
-                if (hwid == mpidr) {
-                        cpu_read_ops(dn, 0);
-                        of_node_put(dn);
-                        return;
-                }
+        struct device_node *dn = of_get_cpu_node(0, NULL);
+        if (!dn) {
+                pr_err("Failed to find device node for boot cpu\n");
+                return;
         }
+        cpu_read_ops(dn, 0);
 }