SPM: Implement global response buffer helpers

This buffer is where all the responses from Secure Partitions are stored
until they are requested.

Change-Id: Iafeb8f0848c5ff6f3e187060cd3a47702484dc45
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

diff --git a/include/plat/arm/common/arm_spm_def.h b/include/plat/arm/common/arm_spm_def.h
index 5c7ca90aba901cf7f771068a651d7462b52ca82b..bf3cb8fa03343bc5d6607333d00689d9bf2f5d07 100644 (file)
--- a/include/plat/arm/common/arm_spm_def.h
+++ b/include/plat/arm/common/arm_spm_def.h
@@ -139,5 +139,6 @@
 #define PLAT_SPM_SERVICES_MAX          U(30)
 
 #define PLAT_SPCI_HANDLES_MAX_NUM      U(20)
+#define PLAT_SPM_RESPONSES_MAX         U(30)
 
 #endif /* ARM_SPM_DEF_H */

diff --git a/services/std_svc/spm/spm.mk b/services/std_svc/spm/spm.mk
index a191f6ff11c70801ff7083a40cecddbd770c6787..b52292d6f48ade47e592d5dbf9c1a2bc6744112b 100644 (file)
--- a/services/std_svc/spm/spm.mk
+++ b/services/std_svc/spm/spm.mk
@@ -19,6 +19,7 @@ SPM_SOURCES   :=      $(addprefix services/std_svc/spm/,      \
                        sp_setup.c                              \
                        sp_xlat.c                               \
                        spci.c                                  \
+                       spm_buffers.c                           \
                        spm_main.c                              \
                        sprt.c)                                 \
                        ${SPRT_LIB_SOURCES}

diff --git a/services/std_svc/spm/spm_buffers.c b/services/std_svc/spm/spm_buffers.c
new file mode 100644 (file)
index 0000000..747337a
--- /dev/null
+++ b/services/std_svc/spm/spm_buffers.c
@@ -0,0 +1,108 @@
+/*
+ * Copyright (c) 2018, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <arch_helpers.h>
+#include <platform_def.h>
+#include <spinlock.h>
+#include <utils_def.h>
+
+/*******************************************************************************
+ * Secure Service response global array. All the responses to the requests done
+ * to the Secure Partition are stored here. They are removed from the array as
+ * soon as their value is read.
+ ******************************************************************************/
+struct sprt_response {
+       int is_valid;
+       uint32_t token;
+       uint16_t client_id, handle;
+       u_register_t x1, x2, x3;
+};
+
+static struct sprt_response responses[PLAT_SPM_RESPONSES_MAX];
+
+static spinlock_t responses_lock;
+
+/* Add response to the global response buffer. Returns 0 on success else -1. */
+int spm_response_add(uint16_t client_id, uint16_t handle, uint32_t token,
+                    u_register_t x1, u_register_t x2, u_register_t x3)
+{
+       spin_lock(&responses_lock);
+
+       /* Make sure that there isn't any other response with the same token. */
+       for (unsigned int i = 0U; i < ARRAY_SIZE(responses); i++) {
+               struct sprt_response *resp = &(responses[i]);
+
+               if ((resp->is_valid == 1) && (resp->token == token)) {
+                       return -1;
+               }
+       }
+
+       for (int i = 0; i < ARRAY_SIZE(responses); i++) {
+               struct sprt_response *resp = &(responses[i]);
+
+               if (resp->is_valid == 0) {
+                       resp->token = token;
+                       resp->client_id = client_id;
+                       resp->handle = handle;
+                       resp->x1 = x1;
+                       resp->x2 = x2;
+                       resp->x3 = x3;
+
+                       dmbish();
+
+                       resp->is_valid = 1;
+
+                       spin_unlock(&responses_lock);
+
+                       return 0;
+               }
+       }
+
+       spin_unlock(&responses_lock);
+
+       return -1;
+}
+
+/*
+ * Returns a response from the requests array and removes it from it. Returns 0
+ * on success, -1 if it wasn't found.
+ */
+int spm_response_get(uint16_t client_id, uint16_t handle, uint32_t token,
+                    u_register_t *x1, u_register_t *x2, u_register_t *x3)
+{
+       spin_lock(&responses_lock);
+
+       for (unsigned int i = 0U; i < ARRAY_SIZE(responses); i++) {
+               struct sprt_response *resp = &(responses[i]);
+
+               /* Ignore invalid entries */
+               if (resp->is_valid == 0) {
+                       continue;
+               }
+
+               /* Make sure that all the information matches the stored one */
+               if ((resp->token != token) || (resp->client_id != client_id) ||
+                   (resp->handle != handle)) {
+                       continue;
+               }
+
+               *x1 = resp->x1;
+               *x2 = resp->x2;
+               *x3 = resp->x3;
+
+               dmbish();
+
+               resp->is_valid = 0;
+
+               spin_unlock(&responses_lock);
+
+               return 0;
+       }
+
+       spin_unlock(&responses_lock);
+
+       return -1;
+}

diff --git a/services/std_svc/spm/spm_private.h b/services/std_svc/spm/spm_private.h
index a7bd760bd725463abae5d890209788df4a471252..7216003bfd62c283671153c4d6b2789d8059b24c 100644 (file)
--- a/services/std_svc/spm/spm_private.h
+++ b/services/std_svc/spm/spm_private.h
@@ -104,6 +104,12 @@ void spm_cpu_set_sp_ctx(unsigned int linear_id, sp_context_t *sp_ctx);
 sp_context_t *spm_cpu_get_sp_ctx(unsigned int linear_id);
 sp_context_t *spm_sp_get_by_uuid(const uint32_t (*svc_uuid)[4]);
 
+/* Functions to manipulate response and requests buffers */
+int spm_response_add(uint16_t client_id, uint16_t handle, uint32_t token,
+                    u_register_t x1, u_register_t x2, u_register_t x3);
+int spm_response_get(uint16_t client_id, uint16_t handle, uint32_t token,
+                    u_register_t *x1, u_register_t *x2, u_register_t *x3);
+
 #endif /* __ASSEMBLY__ */
 
 #endif /* SPM_PRIVATE_H */