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>

diff --git a/arch/arm64/kernel/cpu_ops.c b/arch/arm64/kernel/cpu_ops.c
index aa0c9e7..e2ba274 100644 (file)
--- 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);
 }