From e9467afb2d483ccec8f816902624d848e8f21d86 Mon Sep 17 00:00:00 2001
From: Manish V Badarkhe <Manish.Badarkhe@arm.com>
Date: Thu, 16 Jun 2022 13:46:43 +0100
Subject: [PATCH] feat(drtm): retrieve DRTM features

Retrieved below DRTM features via DRTM_FEATURES SMC call -
1. TPM features
2. Minimum memory requirement
3. Boot PE ID
4. DMA protection

Change-Id: Ia6dc497259541ce30a6550afa35d95d9a9a366af
Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
Signed-off-by: Lucian Paul-Trifu <lucian.paultrifu@gmail.com>
---
 include/services/drtm_svc.h       |  9 ++++-
 services/std_svc/drtm/drtm_main.c | 67 +++++++++++++++++++++++++++++++
 2 files changed, 75 insertions(+), 1 deletion(-)

diff --git a/include/services/drtm_svc.h b/include/services/drtm_svc.h
index 890cdbb0e..69b314f08 100644
--- a/include/services/drtm_svc.h
+++ b/include/services/drtm_svc.h
@@ -44,6 +44,12 @@
 #define ARM_DRTM_SVC_SET_TCB_HASH	DRTM_FID(DRTM_FNUM_SVC_SET_TCB_HASH)
 #define ARM_DRTM_SVC_LOCK_TCB_HASH	DRTM_FID(DRTM_FNUM_SVC_LOCK_TCB_HASH)
 
+#define ARM_DRTM_FEATURES_TPM		U(0x1)
+#define ARM_DRTM_FEATURES_MEM_REQ	U(0x2)
+#define ARM_DRTM_FEATURES_DMA_PROT	U(0x3)
+#define ARM_DRTM_FEATURES_BOOT_PE_ID	U(0x4)
+#define ARM_DRTM_FEATURES_TCB_HASHES	U(0x5)
+
 #define is_drtm_fid(_fid) \
 	(((_fid) >= ARM_DRTM_SVC_VERSION) && ((_fid) <= ARM_DRTM_SVC_LOCK_TCB_HASH))
 
@@ -62,9 +68,10 @@
 	ARM_DRTM_VERSION_MINOR_SHIFT))
 
 #define ARM_DRTM_FUNC_SHIFT	U(63)
-#define ARM_DRTM_FUNC_MASK	U(0x1)
+#define ARM_DRTM_FUNC_MASK	ULL(0x1)
 #define ARM_DRTM_FUNC_ID	U(0x0)
 #define ARM_DRTM_FEAT_ID	U(0x1)
+#define ARM_DRTM_FEAT_ID_MASK	ULL(0xff)
 
 /*
  * Definitions for DRTM features as per DRTM beta0 section 3.3,
diff --git a/services/std_svc/drtm/drtm_main.c b/services/std_svc/drtm/drtm_main.c
index 843fc5d35..867870bb5 100644
--- a/services/std_svc/drtm/drtm_main.c
+++ b/services/std_svc/drtm/drtm_main.c
@@ -119,6 +119,36 @@ int drtm_setup(void)
 	return 0;
 }
 
+static inline uint64_t drtm_features_tpm(void *ctx)
+{
+	SMC_RET2(ctx, 1ULL, /* TPM feature is supported */
+		 plat_drtm_features.tpm_features);
+}
+
+static inline uint64_t drtm_features_mem_req(void *ctx)
+{
+	SMC_RET2(ctx, 1ULL, /* memory req Feature is supported */
+		 plat_drtm_features.minimum_memory_requirement);
+}
+
+static inline uint64_t drtm_features_boot_pe_id(void *ctx)
+{
+	SMC_RET2(ctx, 1ULL, /* Boot PE feature is supported */
+		 plat_drtm_features.boot_pe_id);
+}
+
+static inline uint64_t drtm_features_dma_prot(void *ctx)
+{
+	SMC_RET2(ctx, 1ULL, /* DMA protection feature is supported */
+		 plat_drtm_features.dma_prot_features);
+}
+
+static inline uint64_t drtm_features_tcb_hashes(void *ctx)
+{
+	SMC_RET2(ctx, 1ULL, /* TCB hash feature is supported */
+		 plat_drtm_features.tcb_hash_features);
+}
+
 uint64_t drtm_smc_handler(uint32_t smc_fid,
 			  uint64_t x1,
 			  uint64_t x2,
@@ -192,6 +222,43 @@ uint64_t drtm_smc_handler(uint32_t smc_fid,
 				SMC_RET1(handle, NOT_SUPPORTED);
 				break;	/* not reached */
 			}
+		} else {
+			/* Dispatch feature-based queries. */
+			switch (x1 & ARM_DRTM_FEAT_ID_MASK) {
+			case ARM_DRTM_FEATURES_TPM:
+				INFO("++ DRTM service handler: TPM features\n");
+				return drtm_features_tpm(handle);
+				break;	/* not reached */
+
+			case ARM_DRTM_FEATURES_MEM_REQ:
+				INFO("++ DRTM service handler: Min. mem."
+				     " requirement features\n");
+				return drtm_features_mem_req(handle);
+				break;	/* not reached */
+
+			case ARM_DRTM_FEATURES_DMA_PROT:
+				INFO("++ DRTM service handler: "
+				     "DMA protection features\n");
+				return drtm_features_dma_prot(handle);
+				break;	/* not reached */
+
+			case ARM_DRTM_FEATURES_BOOT_PE_ID:
+				INFO("++ DRTM service handler: "
+				     "Boot PE ID features\n");
+				return drtm_features_boot_pe_id(handle);
+				break;	/* not reached */
+
+			case ARM_DRTM_FEATURES_TCB_HASHES:
+				INFO("++ DRTM service handler: "
+				     "TCB-hashes features\n");
+				return drtm_features_tcb_hashes(handle);
+				break;	/* not reached */
+
+			default:
+				ERROR("Unknown ARM DRTM service feature\n");
+				SMC_RET1(handle, NOT_SUPPORTED);
+				break;	/* not reached */
+			}
 		}
 
 	case ARM_DRTM_SVC_UNPROTECT_MEM:
-- 
2.39.5