--- zzzz-none-000/linux-4.19.183/drivers/firmware/psci.c	2021-03-24 10:07:39.000000000 +0000
+++ bcm63-7530ax-756/linux-4.19.183/drivers/firmware/psci.c	2023-06-28 08:54:19.000000000 +0000
@@ -46,6 +46,11 @@
 #define PSCI_FN_NATIVE(version, name)	PSCI_##version##_FN_##name
 #endif
 
+#if defined(CONFIG_BCM_KF_ATF)
+void __weak pmc_spin_lock(void) {}
+void __weak pmc_spin_unlock(void) {}
+#endif
+
 /*
  * The CPU any Trusted OS is resident on. The trusted OS may reject CPU_OFF
  * calls to its resident CPU, so we must avoid issuing those. We never migrate
@@ -180,8 +185,14 @@
 	int err;
 	u32 fn;
 
+#if defined(CONFIG_BCM_KF_ATF)
+	pmc_spin_lock();
+#endif
 	fn = psci_function_id[PSCI_FN_CPU_ON];
 	err = invoke_psci_fn(fn, cpuid, entry_point, 0);
+#if defined(CONFIG_BCM_KF_ATF)
+	pmc_spin_unlock();
+#endif
 	return psci_to_linux_errno(err);
 }