Add protocol version check during probing
To ensure that the Linux kernel NPU driver and the firmware used are
compatible, the NPU driver will now request and verify the protocol
version when setting up the device during the probing.
Change-Id: I13bca96bf6f98ca90dc79e11ae637c269c2a5eec
Signed-off-by: Mikael Olsson <mikael.olsson@arm.com>
diff --git a/kernel/ethosu_version.c b/kernel/ethosu_version.c
new file mode 100644
index 0000000..1a92dc2
--- /dev/null
+++ b/kernel/ethosu_version.c
@@ -0,0 +1,149 @@
+/*
+ * Copyright 2023 Arm Limited and/or its affiliates
+ *
+ * This program is free software and is provided to you under the terms of the
+ * GNU General Public License version 2 as published by the Free Software
+ * Foundation, and any use by you of this program is subject to the terms
+ * of such GNU licence.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ */
+
+/****************************************************************************
+ * Includes
+ ****************************************************************************/
+
+#include "ethosu_version.h"
+
+#include "ethosu_core_rpmsg.h"
+
+#include <linux/errno.h>
+
+/****************************************************************************
+ * Defines
+ ****************************************************************************/
+
+#define VERSION_RESP_TIMEOUT_MS 2000
+
+/****************************************************************************
+ * Functions
+ ****************************************************************************/
+
+static void ethosu_version_fail(struct ethosu_mailbox_msg *msg)
+{
+ struct ethosu_version *version =
+ container_of(msg, typeof(*version), msg);
+
+ if (completion_done(&version->done))
+ return;
+
+ version->errno = -EFAULT;
+ complete(&version->done);
+}
+
+void ethosu_version_rsp(struct ethosu_mailbox *mailbox,
+ int msg_id,
+ struct ethosu_core_msg_version_rsp *rsp)
+{
+ struct device *dev = mailbox->dev;
+ struct ethosu_mailbox_msg *msg;
+ struct ethosu_version *version;
+
+ msg = ethosu_mailbox_find(mailbox, msg_id,
+ ETHOSU_CORE_MSG_VERSION_REQ);
+ if (IS_ERR(msg)) {
+ dev_warn(dev,
+ "Id for version msg not found. Id=0x%0x: %ld\n",
+ msg_id, PTR_ERR(msg));
+
+ return;
+ }
+
+ version = container_of(msg, typeof(*version), msg);
+
+ if (completion_done(&version->done))
+ return;
+
+ if (rsp->major != ETHOSU_CORE_MSG_VERSION_MAJOR ||
+ rsp->minor != ETHOSU_CORE_MSG_VERSION_MINOR) {
+ dev_warn(dev,
+ "Msg: Protocol version mismatch. Expected %u.%u.X but got %u.%u.%u",
+ ETHOSU_CORE_MSG_VERSION_MAJOR,
+ ETHOSU_CORE_MSG_VERSION_MINOR,
+ rsp->major, rsp->minor, rsp->patch);
+ version->errno = -EPROTO;
+ } else {
+ version->errno = 0;
+ }
+
+ complete(&version->done);
+}
+
+int ethosu_version_check_request(struct device *dev,
+ struct ethosu_mailbox *mailbox)
+{
+ struct ethosu_version *version;
+ int ret;
+ int timeout;
+
+ version = devm_kzalloc(dev, sizeof(*version), GFP_KERNEL);
+ if (!version)
+ return -ENOMEM;
+
+ version->dev = dev;
+ init_completion(&version->done);
+ version->msg.fail = ethosu_version_fail;
+
+ ret = ethosu_mailbox_register(mailbox, &version->msg);
+ if (ret < 0)
+ goto free_version;
+
+ dev_dbg(dev, "Protocol version request created. Id=0x%x, handle=%pK\n",
+ version->msg.id, version);
+
+ ret = ethosu_mailbox_version_request(mailbox, &version->msg);
+ if (ret)
+ goto deregister;
+
+ /* Unlock the mutex to not block other messages while waiting */
+ device_unlock(dev);
+
+ /* Wait for version response */
+ timeout = wait_for_completion_timeout(&version->done,
+ msecs_to_jiffies(
+ VERSION_RESP_TIMEOUT_MS));
+
+ /* Take back the mutex before resuming to do anything */
+ device_lock(dev);
+
+ if (0 == timeout) {
+ dev_warn(dev, "Protocol version response timeout");
+ ret = -ETIME;
+ goto deregister;
+ }
+
+ if (version->errno) {
+ ret = version->errno;
+ goto deregister;
+ }
+
+deregister:
+ ethosu_mailbox_deregister(mailbox, &version->msg);
+
+free_version:
+ dev_dbg(dev, "Protocol version destroy. Id=0x%x, handle=%pK\n",
+ version->msg.id,
+ version);
+ devm_kfree(dev, version);
+
+ return ret;
+}