diff --git a/docs/porting-guide.rst b/docs/porting-guide.rst
index 1250071..8182f91 100644
--- a/docs/porting-guide.rst
+++ b/docs/porting-guide.rst
@@ -2818,6 +2818,17 @@
 for the higher power domain levels depending on the result of state
 coordination. The generic code expects the handler to succeed.
 
+plat_psci_ops.pwr_domain_validate_suspend() [optional]
+......................................................
+
+This is an optional function that is only compiled into the build if the build
+option ``PSCI_OS_INIT_MODE`` is enabled.
+
+If implemented, this function allows the platform to perform platform specific
+validations based on hardware states. The generic code expects this function to
+return PSCI_E_SUCCESS on success, or either PSCI_E_DENIED or
+PSCI_E_INVALID_PARAMS as appropriate for any invalid requests.
+
 plat_psci_ops.pwr_domain_suspend_pwrdown_early() [optional]
 ...........................................................
 
@@ -2876,10 +2887,6 @@
 data, for example in DRAM. The Distributor can then be powered down using an
 implementation-defined sequence.
 
-If the build option ``PSCI_OS_INIT_MODE`` is enabled, the generic code expects
-the platform to return PSCI_E_SUCCESS on success, or either PSCI_E_DENIED or
-PSCI_E_INVALID_PARAMS as appropriate for any invalid requests.
-
 plat_psci_ops.pwr_domain_pwr_down_wfi()
 .......................................