diff --git a/src/soc/amd/cezanne/fsp_m_params.c b/src/soc/amd/cezanne/fsp_m_params.c
index cfe934b64b..ba2663a413 100644
--- a/src/soc/amd/cezanne/fsp_m_params.c
+++ b/src/soc/amd/cezanne/fsp_m_params.c
@@ -150,7 +150,10 @@ void platform_fsp_memory_init_params_cb(FSPM_UPD *mupd, uint32_t version)
 	mcfg->sata_enable = is_dev_enabled(DEV_PTR(sata_0)) || is_dev_enabled(DEV_PTR(sata_1));
 
 	if (config->usb_phy_custom) {
-		mcfg->usb_phy = (struct usb_phy_config *)&config->usb_phy;
+		/* devicetree config is const, use local copy */
+		static struct usb_phy_config lcl_usb_phy;
+		lcl_usb_phy = config->usb_phy;
+		mcfg->usb_phy = &lcl_usb_phy;
 		mcfg->usb_phy->Version_Major = FSP_USB_STRUCT_MAJOR_VERSION;
 		mcfg->usb_phy->Version_Minor = FSP_USB_STRUCT_MINOR_VERSION;
 		mcfg->usb_phy->TableLength = sizeof(struct usb_phy_config);