fix(plat/arm): fix SP count limit without dual root CoT

Remove reserved range for platform provider owned SPs if the dual root
CoT is disabled and allow SPs to populate the range up to MAX_SP_IDS.

Signed-off-by: Imre Kis <imre.kis@arm.com>
Change-Id: Ib4ec18f6530d2515ada21d2c0c388d55aa479d26
diff --git a/plat/arm/common/fconf/arm_fconf_sp.c b/plat/arm/common/fconf/arm_fconf_sp.c
index 95e0873..18c83c7 100644
--- a/plat/arm/common/fconf/arm_fconf_sp.c
+++ b/plat/arm/common/fconf/arm_fconf_sp.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020-2021, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2020-2022, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -30,13 +30,16 @@
 	union uuid_helper_t uuid_helper;
 	unsigned int index = 0;
 	uint32_t val32;
-	bool is_plat_owned = false;
 	const unsigned int sip_start = SP_PKG1_ID;
 	unsigned int sip_index = sip_start;
+#if defined(ARM_COT_dualroot)
 	const unsigned int sip_end = sip_start + MAX_SP_IDS / 2;
+	/* Allocating index range for platform SPs */
 	const unsigned int plat_start = SP_PKG5_ID;
 	unsigned int plat_index = plat_start;
 	const unsigned int plat_end = plat_start + MAX_SP_IDS / 2;
+	bool is_plat_owned = false;
+#endif /* ARM_COT_dualroot */
 
 	/* As libfdt use void *, we can't avoid this cast */
 	const void *dtb = (void *)config;
@@ -51,12 +54,18 @@
 	}
 
 	fdt_for_each_subnode(sp_node, dtb, node) {
-		if ((index == MAX_SP_IDS) || (sip_index == sip_end)
-		    || (plat_index == plat_end)) {
+		if (index == MAX_SP_IDS) {
 			ERROR("FCONF: Reached max number of SPs\n");
 			return -1;
 		}
 
+#if defined(ARM_COT_dualroot)
+		if ((sip_index == sip_end) || (plat_index == plat_end)) {
+			ERROR("FCONF: Reached max number of plat/SiP SPs\n");
+			return -1;
+		}
+#endif /* ARM_COT_dualroot */
+
 		/* Read UUID */
 		err = fdtw_read_uuid(dtb, sp_node, "uuid", 16,
 				     (uint8_t *)&uuid_helper);
@@ -96,7 +105,7 @@
 		/* Owner is an optional field, no need to catch error */
 		fdtw_read_string(dtb, sp_node, "owner",
 				arm_sp.owner[index], ARM_SP_OWNER_NAME_LEN);
-#endif
+
 		/* If owner is empty mark it as SiP owned */
 		if ((strncmp(arm_sp.owner[index], "SiP",
 			     ARM_SP_OWNER_NAME_LEN) == 0) ||
@@ -121,7 +130,9 @@
 			policies[plat_index].dev_handle = &fip_dev_handle;
 			policies[plat_index].check = open_fip;
 			plat_index++;
-		} else {
+		} else
+#endif /* ARM_COT_dualroot */
+		{
 			sp_mem_params_descs[index].image_id = sip_index;
 			policies[sip_index].image_spec =
 						(uintptr_t)&arm_sp.uuids[index];