feat(psa): interface with RSS for NV counters

Adding AP/RSS interface for retrieving and incrementing non-volatile
counters.

The read interface implements the psa_call:
psa_call(RSS_PLATFORM_SERVICE_HANDLE,
         RSS_PLATFORM_API_ID_NV_READ,
         in_vec, 1, out_vec, 1);

where the in_vec indicates which of the 3 counters we want, and the
out_vec stores the counter value we get back from RSS.

The increment interface implements the psa_call:
psa_call(RSS_PLATFORM_SERVICE_HANDLE,
         RSS_PLATFORM_API_ID_NV_INCREMENT,
         in_vec, 1, (psa_outvec *)NULL, 0);

where, again, in_vec indicates the counter to increment, and we don't
get any output parameter from RSS.

Through this service, we will be able to get/increment any of the 3 NV
counters used on a CCA platform:
- NV counter for CCA firmware (BL2, BL31, RMM).
- NV counter for secure firmware.
- NV counter for non-secure firmware.

Signed-off-by: Lauren Wehrmeister <lauren.wehrmeister@arm.com>
Signed-off-by: Raef Coles <raef.coles@arm.com>
Change-Id: I4c1c7f4837ebff30de16bb0ce7ecd416b70b1f62

include/lib/psa/psa_manifest/sid.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019-2022, Arm Limited. All rights reserved.
+ * Copyright (c) 2019-2023, Arm Limited. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  *
@@ -8,6 +8,9 @@
 #ifndef PSA_MANIFEST_SID_H
 #define PSA_MANIFEST_SID_H
 
+/******** RSS_SP_PLATFORM ********/
+#define RSS_PLATFORM_SERVICE_HANDLE			(0x40000105U)
+
 /******** PSA_SP_MEASURED_BOOT ********/
 #define RSS_MEASURED_BOOT_HANDLE			(0x40000110U)
 

include/lib/psa/rss_platform_api.h

@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2023, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ */
+
+#ifndef RSS_PLATFORM_API_H
+#define RSS_PLATFORM_API_H
+
+#include <stdint.h>
+
+#include "psa/error.h"
+
+#define RSS_PLATFORM_API_ID_NV_READ       (1010)
+#define RSS_PLATFORM_API_ID_NV_INCREMENT  (1011)
+
+/*
+ * Increments the given non-volatile (NV) counter by one
+ *
+ * counter_id	NV counter ID.
+ *
+ * PSA_SUCCESS if the value is read correctly. Otherwise,
+ *	it returns a PSA_ERROR.
+ */
+psa_status_t
+rss_platform_nv_counter_increment(uint32_t counter_id);
+
+/*
+ * Reads the given non-volatile (NV) counter
+ *
+ * counter_id	NV counter ID.
+ * size		Size of the buffer to store NV counter value
+ *			in bytes.
+ * val		Pointer to store the current NV counter value.
+ *
+ * PSA_SUCCESS if the value is read correctly. Otherwise,
+ *	it returns a PSA_ERROR.
+ */
+psa_status_t
+rss_platform_nv_counter_read(uint32_t counter_id,
+		uint32_t size, uint8_t *val);
+
+#endif /* RSS_PLATFORM_API_H */

lib/psa/rss_platform.c

@@ -0,0 +1,43 @@
+/*
+ * Copyright (c) 2023, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ */
+
+#include <stdint.h>
+
+#include <psa/client.h>
+#include <psa_manifest/sid.h>
+#include <rss_platform_api.h>
+
+psa_status_t
+rss_platform_nv_counter_increment(uint32_t counter_id)
+{
+	struct psa_invec in_vec[1];
+
+	in_vec[0].base = &counter_id;
+	in_vec[0].len = sizeof(counter_id);
+
+	return psa_call(RSS_PLATFORM_SERVICE_HANDLE,
+			RSS_PLATFORM_API_ID_NV_INCREMENT,
+			in_vec, 1, NULL, 0);
+}
+
+psa_status_t
+rss_platform_nv_counter_read(uint32_t counter_id,
+		uint32_t size, uint8_t *val)
+{
+	struct psa_invec in_vec[1];
+	struct psa_outvec out_vec[1];
+
+	in_vec[0].base = &counter_id;
+	in_vec[0].len = sizeof(counter_id);
+
+	out_vec[0].base = val;
+	out_vec[0].len = size;
+
+	return psa_call(RSS_PLATFORM_SERVICE_HANDLE,
+			RSS_PLATFORM_API_ID_NV_READ,
+			in_vec, 1, out_vec, 1);
+}