@@ -6,6 +6,8 @@
* Copyright (c) 2017, Intel Corporation. All rights reserved.
* Copyright (C) 2020 Linaro Ltd. <sughosh.ganu@linaro.org>
* Copyright (C) 2020 Linaro Ltd. <ilias.apalodimas@linaro.org>
+ * (C) Copyright 2022 ARM Limited
+ * Abdellatif El Khlifi <abdellatif.elkhlifi@arm.com>
*/
#ifndef _MM_COMMUNICATION_H_
@@ -13,6 +15,9 @@
#include <part_efi.h>
+/* MM service UUID string (big-endian format). This UUID is common across all MM SPs */
+#define MM_SP_UUID "33d532ed-e699-0942-c09c-a798d9cd722d"
+
/*
* Interface to the pseudo Trusted Application (TA), which provides a
* communication channel with the Standalone MM (Management Mode)
@@ -55,13 +55,23 @@ config EFI_VARIABLE_FILE_STORE
stored as file /ubootefi.var on the EFI system partition.
config EFI_MM_COMM_TEE
- bool "UEFI variables storage service via OP-TEE"
- depends on OPTEE
+ bool "UEFI variables storage service via the trusted world"
+ depends on OPTEE || ARM_FFA_TRANSPORT
help
+ Allowing access to the MM SP services (SPs such as StandAlonneMM, smm-gateway).
+ When using the u-boot OP-TEE driver, StandAlonneMM is supported.
+ When using the u-boot FF-A driver any MM SP is supported.
+
If OP-TEE is present and running StandAloneMM, dispatch all UEFI
variable related operations to that. The application will verify,
authenticate and store the variables on an RPMB.
+ When ARM_FFA_TRANSPORT is used, dispatch all UEFI variable related
+ operations to the MM SP running in the secure world.
+ A door bell mechanism is used to notify the SP when there is data in the shared
+ MM buffer. The data is copied by u-boot to the shared buffer before issuing
+ the door bell event.
+
config EFI_VARIABLE_NO_STORE
bool "Don't persist non-volatile UEFI variables"
help
@@ -4,9 +4,12 @@
*
* Copyright (C) 2019 Linaro Ltd. <sughosh.ganu@linaro.org>
* Copyright (C) 2019 Linaro Ltd. <ilias.apalodimas@linaro.org>
+ * Copyright (C) 2022 ARM Limited
+ * Abdellatif El Khlifi <abdellatif.elkhlifi@arm.com>
*/
#include <common.h>
+#include <dm.h>
#include <efi.h>
#include <efi_api.h>
#include <efi_loader.h>
@@ -15,6 +18,36 @@
#include <malloc.h>
#include <mm_communication.h>
+#if (IS_ENABLED(CONFIG_ARM_FFA_TRANSPORT))
+
+#include <arm_ffa.h>
+#include <cpu_func.h>
+#include <mapmem.h>
+
+#ifndef FFA_SHARED_MM_BUFFER_SIZE
+#error "FFA_SHARED_MM_BUFFER_SIZE must be defined in include/configs/<board>.h"
+#define FFA_SHARED_MM_BUFFER_SIZE 0
+#endif
+
+#ifndef FFA_SHARED_MM_BUFFER_OFFSET
+#error "FFA_SHARED_MM_BUFFER_OFFSET must be defined in include/configs/<board>.h"
+#define FFA_SHARED_MM_BUFFER_OFFSET 0
+#endif
+
+#ifndef FFA_SHARED_MM_BUFFER_ADDR
+#error "FFA_SHARED_MM_BUFFER_ADDR must be defined in include/configs/<board>.h"
+#define FFA_SHARED_MM_BUFFER_ADDR 0
+#endif
+
+/* MM return codes */
+#define MM_SUCCESS (0)
+
+static const char *mm_sp_svc_uuid = MM_SP_UUID;
+
+static u16 mm_sp_id;
+
+#endif
+
extern struct efi_var_file __efi_runtime_data *efi_var_buf;
static efi_uintn_t max_buffer_size; /* comm + var + func + data */
static efi_uintn_t max_payload_size; /* func + data */
@@ -24,6 +57,7 @@ struct mm_connection {
u32 session;
};
+#if (IS_ENABLED(CONFIG_OPTEE))
/**
* get_connection() - Retrieve OP-TEE session for a specific UUID.
*
@@ -143,13 +177,248 @@ static efi_status_t optee_mm_communicate(void *comm_buf, ulong dsize)
return ret;
}
+#endif
+
+#if (IS_ENABLED(CONFIG_ARM_FFA_TRANSPORT))
/**
- * mm_communicate() - Adjust the cmonnucation buffer to StandAlonneMM and send
+ * ffa_notify_mm_sp() - Announce there is data in the shared buffer
+ *
+ * Notifies the MM partition in the trusted world that
+ * data is available in the shared buffer.
+ * This is a blocking call during which trusted world has exclusive access
+ * to the MM shared buffer.
+ *
+ * Return:
+ *
+ * 0 on success
+ */
+static int ffa_notify_mm_sp(void)
+{
+ struct ffa_send_direct_data msg = {0};
+ int ret;
+ int sp_event_ret = -1;
+
+ if (!ffa_bus_ops_get())
+ return -EINVAL;
+
+ msg.data0 = FFA_SHARED_MM_BUFFER_OFFSET; /* x3 */
+
+ ret = ffa_bus_ops_get()->sync_send_receive(NULL, mm_sp_id, &msg, 1);
+ if (ret != 0)
+ return ret;
+
+ sp_event_ret = msg.data0; /* x3 */
+
+ if (sp_event_ret == MM_SUCCESS)
+ return 0;
+
+ /*
+ * Failure to notify the MM SP
+ */
+
+ return -EACCES;
+}
+
+/**
+ * ffa_discover_mm_sp_id() - Query the MM partition ID
+ *
+ * Use the FF-A driver to get the MM partition ID.
+ * If multiple partitions are found, use the first one.
+ * This is a boot time function.
+ *
+ * Return:
+ *
+ * 0 on success
+ */
+static int ffa_discover_mm_sp_id(void)
+{
+ u32 count = 0;
+ int ret;
+ struct ffa_partition_info *parts_info;
+
+ if (!ffa_bus_ops_get())
+ return -EINVAL;
+
+ /*
+ * get from the driver the count of the SPs matching the UUID
+ */
+ ret = ffa_bus_ops_get()->partition_info_get(NULL, mm_sp_svc_uuid, &count, NULL);
+ if (ret != 0) {
+ log_err("EFI: Failure in querying partitions count (error code: %d)\n", ret);
+ return ret;
+ }
+
+ if (!count) {
+ log_info("EFI: No MM partition found\n");
+ return ret;
+ }
+
+ /*
+ * pre-allocate a buffer to be filled by the driver
+ * with ffa_partition_info structs
+ */
+
+ log_info("EFI: Pre-allocating %d partition(s) info structures\n", count);
+
+ parts_info = calloc(count, sizeof(*parts_info));
+ if (!parts_info)
+ return -ENOMEM;
+
+ /*
+ * ask the driver to fill the
+ * buffer with the SPs info
+ */
+ ret = ffa_bus_ops_get()->partition_info_get(NULL, mm_sp_svc_uuid, &count, parts_info);
+ if (ret) {
+ log_err("EFI: Failure in querying partition(s) info (error code: %d)\n", ret);
+ free(parts_info);
+ return ret;
+ }
+
+ /*
+ * MM SPs found , use the first one
+ */
+
+ mm_sp_id = parts_info[0].id;
+
+ log_info("EFI: MM partition ID 0x%x\n", mm_sp_id);
+
+ free(parts_info);
+
+ return 0;
+}
+
+/**
+ * ffa_mm_communicate() - Exchange EFI services data with the MM partition using FF-A
+ * @comm_buf: locally allocated communication buffer used for rx/tx
+ * @dsize: communication buffer size
+ *
+ * Issues a door bell event to notify the MM partition (SP) running in OP-TEE
+ * that there is data to read from the shared buffer.
+ * Communication with the MM SP is performed using FF-A transport.
+ * On the event, MM SP can read the data from the buffer and
+ * update the MM shared buffer with response data.
+ * The response data is copied back to the communication buffer.
+ *
+ * Return:
+ *
+ * EFI status code
+ */
+static efi_status_t ffa_mm_communicate(void *comm_buf, ulong comm_buf_size)
+{
+ ulong tx_data_size;
+ int ffa_ret;
+ efi_status_t efi_ret;
+ struct efi_mm_communicate_header *mm_hdr;
+ void *virt_shared_buf;
+
+ if (!comm_buf)
+ return EFI_INVALID_PARAMETER;
+
+ /* Discover MM partition ID at boot time */
+ if (!mm_sp_id && ffa_discover_mm_sp_id() != 0) {
+ log_err("EFI: Failure to discover MM partition ID at boot time\n");
+ return EFI_UNSUPPORTED;
+ }
+
+ mm_hdr = (struct efi_mm_communicate_header *)comm_buf;
+ tx_data_size = mm_hdr->message_len + sizeof(efi_guid_t) + sizeof(size_t);
+
+ if (comm_buf_size != tx_data_size || tx_data_size > FFA_SHARED_MM_BUFFER_SIZE)
+ return EFI_INVALID_PARAMETER;
+
+ /* Copy the data to the shared buffer */
+
+ virt_shared_buf = (void *)map_sysmem((phys_addr_t)FFA_SHARED_MM_BUFFER_ADDR, 0);
+ memcpy(virt_shared_buf, comm_buf, tx_data_size);
+
+ /*
+ * The secure world might have cache disabled for
+ * the device region used for shared buffer (which is the case for Optee).
+ * In this case, the secure world reads the data from DRAM.
+ * Let's flush the cache so the DRAM is updated with the latest data.
+ */
+ #ifdef CONFIG_ARM64
+ invalidate_dcache_all();
+ #endif
+
+ /* Announce there is data in the shared buffer */
+
+ ffa_ret = ffa_notify_mm_sp();
+
+ switch (ffa_ret) {
+ case 0:
+ {
+ ulong rx_data_size;
+ /* Copy the MM SP response from the shared buffer to the communication buffer */
+ rx_data_size = ((struct efi_mm_communicate_header *)virt_shared_buf)->message_len +
+ sizeof(efi_guid_t) +
+ sizeof(size_t);
+
+ if (rx_data_size > comm_buf_size) {
+ efi_ret = EFI_OUT_OF_RESOURCES;
+ break;
+ }
+
+ memcpy(comm_buf, virt_shared_buf, rx_data_size);
+ efi_ret = EFI_SUCCESS;
+ break;
+ }
+ case -EINVAL:
+ efi_ret = EFI_DEVICE_ERROR;
+ break;
+ case -EPERM:
+ efi_ret = EFI_INVALID_PARAMETER;
+ break;
+ case -EACCES:
+ efi_ret = EFI_ACCESS_DENIED;
+ break;
+ case -EBUSY:
+ efi_ret = EFI_OUT_OF_RESOURCES;
+ break;
+ default:
+ efi_ret = EFI_ACCESS_DENIED;
+ }
+
+ unmap_sysmem(virt_shared_buf);
+ return efi_ret;
+}
+#endif
+
+/**
+ * select_ffa_mm_comms() - checks FF-A support availability
+ *
+ * Making sure FF-A is compiled in. If that's the case try to discover
+ * the FF-A bus.
+ *
+ * Return:
+ *
+ * 0: FF-A ready for use. Otherwise, failure
+ */
+static efi_status_t select_ffa_mm_comms(void)
+{
+ efi_status_t ret = EFI_UNSUPPORTED;
+#if (IS_ENABLED(CONFIG_ARM_FFA_TRANSPORT))
+ ret = ffa_bus_discover(NULL);
+ if (ret)
+ ret = EFI_NOT_READY;
+#endif
+ return ret;
+}
+
+/**
+ * mm_communicate() - Adjust the communication buffer to the MM SP and send
* it to OP-TEE
*
- * @comm_buf: locally allocted communcation buffer
+ * @comm_buf: locally allocated communication buffer
* @dsize: buffer size
+ *
+ * The SP (also called partition) can be any MM SP such as StandAlonneMM or smm-gateway.
+ * The comm_buf format is the same for both partitions.
+ * When using the u-boot OP-TEE driver, StandAlonneMM is supported.
+ * When using the u-boot FF-A driver, any MM SP is supported.
+ *
* Return: status code
*/
static efi_status_t mm_communicate(u8 *comm_buf, efi_uintn_t dsize)
@@ -162,7 +431,17 @@ static efi_status_t mm_communicate(u8 *comm_buf, efi_uintn_t dsize)
mm_hdr = (struct efi_mm_communicate_header *)comm_buf;
var_hdr = (struct smm_variable_communicate_header *)mm_hdr->data;
- ret = optee_mm_communicate(comm_buf, dsize);
+ ret = select_ffa_mm_comms();
+ if (ret != EFI_SUCCESS) {
+#if (IS_ENABLED(CONFIG_OPTEE))
+ ret = optee_mm_communicate(comm_buf, dsize);
+#endif
+ } else {
+#if (IS_ENABLED(CONFIG_ARM_FFA_TRANSPORT))
+ ret = ffa_mm_communicate(comm_buf, dsize);
+#endif
+ }
+
if (ret != EFI_SUCCESS) {
log_err("%s failed!\n", __func__);
return ret;
@@ -258,6 +537,13 @@ efi_status_t EFIAPI get_max_payload(efi_uintn_t *size)
goto out;
}
*size = var_payload->size;
+
+ #if (IS_ENABLED(CONFIG_ARM_FFA_TRANSPORT))
+ if (*size > FFA_SHARED_MM_BUFFER_SIZE)
+ *size = FFA_SHARED_MM_BUFFER_SIZE - MM_COMMUNICATE_HEADER_SIZE -
+ MM_VARIABLE_COMMUNICATE_SIZE;
+ #endif
+
/*
* There seems to be a bug in EDK2 miscalculating the boundaries and
* size checks, so deduct 2 more bytes to fulfill this requirement. Fix
@@ -697,7 +983,7 @@ void efi_variables_boot_exit_notify(void)
ret = EFI_NOT_FOUND;
if (ret != EFI_SUCCESS)
- log_err("Unable to notify StMM for ExitBootServices\n");
+ log_err("Unable to notify the MM partition for ExitBootServices\n");
free(comm_buf);
/*