SPM: Implement SPCI open/close handle SMCs
Introduce SMCs that open and close handles according to the SPCI
specification.
Change-Id: I65f365f15612e01aa445e783e96e48ae275c39fd
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 630a29c..5c7ca90 100644
--- a/include/plat/arm/common/arm_spm_def.h
+++ b/include/plat/arm/common/arm_spm_def.h
@@ -138,4 +138,6 @@
#define PLAT_SPM_NOTIFICATIONS_MAX U(30)
#define PLAT_SPM_SERVICES_MAX U(30)
+#define PLAT_SPCI_HANDLES_MAX_NUM U(20)
+
#endif /* ARM_SPM_DEF_H */
diff --git a/services/std_svc/spm/spci.c b/services/std_svc/spm/spci.c
index 603523f..cb1b8fd 100644
--- a/services/std_svc/spm/spci.c
+++ b/services/std_svc/spm/spci.c
@@ -4,15 +4,245 @@
* SPDX-License-Identifier: BSD-3-Clause
*/
+#include <assert.h>
#include <debug.h>
#include <smccc.h>
#include <smccc_helpers.h>
#include <spci_svc.h>
+#include <spinlock.h>
+#include <string.h>
#include <utils.h>
#include "spm_private.h"
/*******************************************************************************
+ * Macros to print UUIDs.
+ ******************************************************************************/
+#define PRINT_UUID_FORMAT "%08x-%08x-%08x-%08x"
+#define PRINT_UUID_ARGS(x) x[0], x[1], x[2], x[3]
+
+/*******************************************************************************
+ * Array of structs that contains information about all handles of Secure
+ * Services that are currently open.
+ ******************************************************************************/
+typedef enum spci_handle_status {
+ HANDLE_STATUS_CLOSED = 0,
+ HANDLE_STATUS_OPEN,
+} spci_handle_status_t;
+
+typedef struct spci_handle {
+ /* 16-bit value used as reference in all SPCI calls */
+ uint16_t handle;
+
+ /* Client ID of the client that requested the handle */
+ uint16_t client_id;
+
+ /* Current status of the handle */
+ spci_handle_status_t status;
+
+ /*
+ * Context of the Secure Partition that provides the Secure Service
+ * referenced by this handle.
+ */
+ sp_context_t *sp_ctx;
+
+ /*
+ * The same handle might be used for multiple requests, keep a reference
+ * counter of them.
+ */
+ unsigned int num_active_requests;
+} spci_handle_t;
+
+static spci_handle_t spci_handles[PLAT_SPCI_HANDLES_MAX_NUM];
+static spinlock_t spci_handles_lock;
+
+/*
+ * Given a handle and a client ID, return the element of the spci_handles
+ * array that contains the information of the handle. It can only return open
+ * handles. It returns NULL if it couldn't find the element in the array.
+ */
+static spci_handle_t *spci_handle_info_get(uint16_t handle, uint16_t client_id)
+{
+ size_t i;
+
+ for (i = 0; i < ARRAY_SIZE(spci_handles); i++) {
+ spci_handle_t *h = &(spci_handles[i]);
+
+ /* Only check for open handles */
+ if (h->status == HANDLE_STATUS_CLOSED) {
+ continue;
+ }
+
+ /* Check if either the handle or the client ID are different */
+ if ((h->handle != handle) || (h->client_id != client_id)) {
+ continue;
+ }
+
+ return h;
+ }
+
+ return NULL;
+}
+
+/*
+ * Returns a unique value for a handle. This function must be called while
+ * spci_handles_lock is locked. It returns 0 on success, -1 on error.
+ */
+static int spci_create_handle_value(uint16_t *handle)
+{
+ /*
+ * Trivial implementation that relies on the fact that any handle will
+ * be closed before 2^16 more handles have been opened.
+ */
+ static uint16_t handle_count;
+
+ *handle = handle_count;
+
+ handle_count++;
+
+ return 0;
+}
+
+/*******************************************************************************
+ * This function looks for a Secure Partition that has a Secure Service
+ * identified by the given UUID. It returns a handle that the client can use to
+ * access the service, and an SPCI_*** error code.
+ ******************************************************************************/
+static uint64_t spci_service_handle_open_poll(void *handle, u_register_t x1,
+ u_register_t x2, u_register_t x3, u_register_t x4,
+ u_register_t x5, u_register_t x6, u_register_t x7)
+{
+ unsigned int i;
+ sp_context_t *sp_ptr;
+ uint16_t service_handle;
+
+ /* Bits 31:16 of w7 are reserved (MBZ). */
+ assert((x7 & 0xFFFF0000U) == 0);
+
+ uint16_t client_id = x7 & 0x0000FFFFU;
+ uint32_t uuid[4] = { x1, x2, x3, x4 };
+
+ /* Get pointer to the Secure Partition that handles this service */
+ sp_ptr = spm_sp_get_by_uuid(&uuid);
+ if (sp_ptr == NULL) {
+ WARN("SPCI: Service requested by client 0x%04x not found\n",
+ client_id);
+ WARN("SPCI: UUID: " PRINT_UUID_FORMAT "\n",
+ PRINT_UUID_ARGS(uuid));
+
+ SMC_RET2(handle, SPCI_NOT_PRESENT, 0);
+ }
+
+ /* Get lock of the array of handles */
+ spin_lock(&spci_handles_lock);
+
+ /*
+ * We need to record the client ID and Secure Partition that correspond
+ * to this handle. Look for the first free entry in the array.
+ */
+ for (i = 0; i < PLAT_SPCI_HANDLES_MAX_NUM; i++) {
+ if (spci_handles[i].status == HANDLE_STATUS_CLOSED) {
+ break;
+ }
+ }
+
+ if (i == PLAT_SPCI_HANDLES_MAX_NUM) {
+ spin_unlock(&spci_handles_lock);
+
+ WARN("SPCI: Can't open more handles. Client 0x%04x\n",
+ client_id);
+ WARN("SPCI: UUID: " PRINT_UUID_FORMAT "\n",
+ PRINT_UUID_ARGS(uuid));
+
+ SMC_RET2(handle, SPCI_NO_MEMORY, 0);
+ }
+
+ /* Create new handle value */
+ if (spci_create_handle_value(&service_handle) != 0) {
+ spin_unlock(&spci_handles_lock);
+
+ WARN("SPCI: Can't create a new handle value. Client 0x%04x\n",
+ client_id);
+ WARN("SPCI: UUID: " PRINT_UUID_FORMAT "\n",
+ PRINT_UUID_ARGS(uuid));
+
+ SMC_RET2(handle, SPCI_NO_MEMORY, 0);
+ }
+
+ /* Save all information about this handle */
+ spci_handles[i].status = HANDLE_STATUS_OPEN;
+ spci_handles[i].client_id = client_id;
+ spci_handles[i].handle = service_handle;
+ spci_handles[i].num_active_requests = 0U;
+ spci_handles[i].sp_ctx = sp_ptr;
+
+ /* Release lock of the array of handles */
+ spin_unlock(&spci_handles_lock);
+
+ VERBOSE("SPCI: Service handle request by client 0x%04x: 0x%04x\n",
+ client_id, service_handle);
+ VERBOSE("SPCI: UUID: " PRINT_UUID_FORMAT "\n", PRINT_UUID_ARGS(uuid));
+
+ /* The handle is returned in the top 16 bits of x1 */
+ SMC_RET2(handle, SPCI_SUCCESS, ((uint32_t)service_handle) << 16);
+}
+
+/*******************************************************************************
+ * This function closes a handle that a specific client uses to access a Secure
+ * Service. It returns a SPCI_*** error code.
+ ******************************************************************************/
+static uint64_t spci_service_handle_close(void *handle, u_register_t x1)
+{
+ spci_handle_t *handle_info;
+ uint16_t client_id = x1 & 0x0000FFFFU;
+ uint16_t service_handle = (x1 >> 16) & 0x0000FFFFU;
+
+ spin_lock(&spci_handles_lock);
+
+ handle_info = spci_handle_info_get(service_handle, client_id);
+
+ if (handle_info == NULL) {
+ spin_unlock(&spci_handles_lock);
+
+ WARN("SPCI: Tried to close invalid handle 0x%04x by client 0x%04x\n",
+ service_handle, client_id);
+
+ SMC_RET1(handle, SPCI_INVALID_PARAMETER);
+ }
+
+ if (handle_info->status != HANDLE_STATUS_OPEN) {
+ spin_unlock(&spci_handles_lock);
+
+ WARN("SPCI: Tried to close handle 0x%04x by client 0x%04x in status %d\n",
+ service_handle, client_id, handle_info->status);
+
+ SMC_RET1(handle, SPCI_INVALID_PARAMETER);
+ }
+
+ if (handle_info->num_active_requests != 0U) {
+ spin_unlock(&spci_handles_lock);
+
+ /* A handle can't be closed if there are requests left */
+ WARN("SPCI: Tried to close handle 0x%04x by client 0x%04x with %d requests left\n",
+ service_handle, client_id,
+ handle_info->num_active_requests);
+
+ SMC_RET1(handle, SPCI_BUSY);
+ }
+
+ memset(handle_info, 0, sizeof(spci_handle_t));
+
+ handle_info->status = HANDLE_STATUS_CLOSED;
+
+ spin_unlock(&spci_handles_lock);
+
+ VERBOSE("SPCI: Closed handle 0x%04x by client 0x%04x.\n",
+ service_handle, client_id);
+
+ SMC_RET1(handle, SPCI_SUCCESS);
+}
+
+/*******************************************************************************
* This function handles all SMCs in the range reserved for SPCI.
******************************************************************************/
uint64_t spci_smc_handler(uint32_t smc_fid, uint64_t x1, uint64_t x2,
@@ -37,6 +267,24 @@
case SPCI_FID_VERSION:
SMC_RET1(handle, SPCI_VERSION_COMPILED);
+ case SPCI_FID_SERVICE_HANDLE_OPEN:
+ {
+ if ((smc_fid & SPCI_SERVICE_HANDLE_OPEN_NOTIFY_BIT) != 0) {
+ /* Not supported for now */
+ WARN("SPCI_SERVICE_HANDLE_OPEN_NOTIFY not supported.\n");
+ SMC_RET1(handle, SPCI_INVALID_PARAMETER);
+ }
+
+ uint64_t x5 = SMC_GET_GP(handle, CTX_GPREG_X5);
+ uint64_t x6 = SMC_GET_GP(handle, CTX_GPREG_X6);
+ uint64_t x7 = SMC_GET_GP(handle, CTX_GPREG_X7);
+
+ return spci_service_handle_open_poll(handle, x1, x2, x3,
+ x4, x5, x6, x7);
+ }
+ case SPCI_FID_SERVICE_HANDLE_CLOSE:
+ return spci_service_handle_close(handle, x1);
+
default:
break;
}
diff --git a/services/std_svc/spm/spm_main.c b/services/std_svc/spm/spm_main.c
index e8dda0f..ed188d4 100644
--- a/services/std_svc/spm/spm_main.c
+++ b/services/std_svc/spm/spm_main.c
@@ -16,6 +16,7 @@
#include <smccc.h>
#include <smccc_helpers.h>
#include <spinlock.h>
+#include <string.h>
#include <spm_svc.h>
#include <utils.h>
#include <xlat_tables_v2.h>
@@ -45,6 +46,38 @@
}
/*******************************************************************************
+ * This function returns a pointer to the context of the Secure Partition that
+ * handles the service specified by an UUID. It returns NULL if the UUID wasn't
+ * found.
+ ******************************************************************************/
+sp_context_t *spm_sp_get_by_uuid(const uint32_t (*svc_uuid)[4])
+{
+ unsigned int i;
+
+ for (i = 0U; i < PLAT_SPM_MAX_PARTITIONS; i++) {
+
+ sp_context_t *sp_ctx = &sp_ctx_array[i];
+
+ if (sp_ctx->is_present == 0) {
+ continue;
+ }
+
+ struct sp_rd_sect_service *rdsvc;
+
+ for (rdsvc = sp_ctx->rd.service; rdsvc != NULL;
+ rdsvc = rdsvc->next) {
+ uint32_t *rd_uuid = (uint32_t *)(rdsvc->uuid);
+
+ if (memcmp(rd_uuid, svc_uuid, sizeof(rd_uuid)) == 0) {
+ return sp_ctx;
+ }
+ }
+ }
+
+ return NULL;
+}
+
+/*******************************************************************************
* Set state of a Secure Partition context.
******************************************************************************/
void sp_state_set(sp_context_t *sp_ptr, sp_state_t state)
diff --git a/services/std_svc/spm/spm_private.h b/services/std_svc/spm/spm_private.h
index cfd85a3..9a4e82b 100644
--- a/services/std_svc/spm/spm_private.h
+++ b/services/std_svc/spm/spm_private.h
@@ -84,6 +84,7 @@
/* Functions to handle Secure Partition contexts */
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]);
#endif /* __ASSEMBLY__ */