functionfs: add arpc handler

To be able to reply to arpc messages we need to add the arpc header
file, and also handle the arpc run with a request attached.

We use the previously introduces to_ap_arpc endpoint to send a response
to AP. Right now we just reply success to any command, that may change
in the future.

Signed-off-by: Rui Miguel Silva <rmfrfs@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Makefile.am

@@ -7,6 +7,7 @@ bin_PROGRAMS = \
 	gbsim
 
 gbsim_SOURCES = \
+	arpc.h \
 	config.h \
 	connection.c \
 	bootrom.c \

arpc.h

@@ -0,0 +1,109 @@
+/*
+ * This file is provided under a dual BSD/GPLv2 license.  When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright(c) 2016 Google Inc. All rights reserved.
+ * Copyright(c) 2016 Linaro Ltd. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * 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 version 2 for more details.
+ *
+ * BSD LICENSE
+ *
+ * Copyright(c) 2016 Google Inc. All rights reserved.
+ * Copyright(c) 2016 Linaro Ltd. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *  * Neither the name of Google Inc. or Linaro Ltd. nor the names of
+ *    its contributors may be used to endorse or promote products
+ *    derived from this software without specific prior written
+ *    permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GOOGLE INC. OR
+ * LINARO LTD. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __ARPC_H
+#define __ARPC_H
+
+/* APBridgeA RPC (ARPC) */
+
+enum arpc_result {
+	ARPC_SUCCESS		= 0x00,
+	ARPC_NO_MEMORY		= 0x01,
+	ARPC_INVALID		= 0x02,
+	ARPC_TIMEOUT		= 0x03,
+	ARPC_UNKNOWN_ERROR	= 0xff,
+};
+
+struct arpc_request_message {
+	__le16	id;		/* RPC unique id */
+	__le16	size;		/* Size in bytes of header + payload */
+	__u8	type;		/* RPC type */
+	__u8	data[0];	/* ARPC data */
+} __packed;
+
+struct arpc_response_message {
+	__le16	id;		/* RPC unique id */
+	__u8	result;		/* Result of RPC */
+} __packed;
+
+
+/* ARPC requests */
+#define ARPC_TYPE_CPORT_CONNECTED		0x01
+#define ARPC_TYPE_CPORT_QUIESCE			0x02
+#define ARPC_TYPE_CPORT_CLEAR			0x03
+#define ARPC_TYPE_CPORT_FLUSH			0x04
+#define ARPC_TYPE_CPORT_SHUTDOWN		0x05
+
+struct arpc_cport_connected_req {
+	__le16 cport_id;
+} __packed;
+
+struct arpc_cport_quiesce_req {
+	__le16 cport_id;
+	__le16 peer_space;
+	__le16 timeout;
+} __packed;
+
+struct arpc_cport_clear_req {
+	__le16 cport_id;
+} __packed;
+
+struct arpc_cport_flush_req {
+	__le16 cport_id;
+} __packed;
+
+struct arpc_cport_shutdown_req {
+	__le16 cport_id;
+	__le16 timeout;
+	__u8 phase;
+} __packed;
+
+#endif	/* __ARPC_H */

functionfs.c

@@ -25,6 +25,7 @@
 #include <linux/usb/functionfs.h>
 
 #include "gbsim.h"
+#include "arpc.h"
 #include "config.h"
 
 #define FFS_PREFIX		"/dev/ffs-gbsim/"
@@ -267,6 +268,46 @@ static int dump_control_msg(const struct usb_ctrlrequest *setup)
 	return count;
 }
 
+static void arpc_response_send(const struct usb_ctrlrequest *setup)
+{
+	uint8_t buf[256];
+	struct arpc_request_message *arpc_req;
+	struct arpc_response_message arpc_rsp;
+	uint16_t arpc_size;
+	int count;
+
+	arpc_size = le16toh(setup->wLength);
+	if (arpc_size < sizeof(*arpc_req))
+		gbsim_debug("arpc run received with the wrong size: %u : %lu\n",
+			    arpc_size, sizeof(*arpc_req));
+
+	count = read(control, buf, arpc_size);
+	if (count < 0) {
+		perror("ARPC: Failed to read\n");
+		return;
+	}
+
+	arpc_req = (struct arpc_request_message *)buf;
+	if (verbose) {
+		gbsim_debug("AP->ARPC message\n");
+		gbsim_debug("   id	= 0x%04x\n", le16toh(arpc_req->id));
+		gbsim_debug("   size	= 0x%04x\n", le16toh(arpc_req->size));
+		gbsim_debug("   type	= 0x%02x\n", arpc_req->type);
+	}
+
+	/*
+	 * we reply success to every arpc request, as we are not doing anything
+	 * with the it...yet.
+	 */
+	arpc_rsp.id = arpc_req->id;
+	arpc_rsp.result = ARPC_SUCCESS;
+
+	count = write(to_ap_arpc, &arpc_rsp,
+		      sizeof(struct arpc_response_message));
+	if (count < 0)
+		perror("ARPC: Failed to write\n");
+}
+
 static void handle_setup(const struct usb_ctrlrequest *setup)
 {
 	uint16_t count;
@@ -325,6 +366,9 @@ static void handle_setup(const struct usb_ctrlrequest *setup)
 		gbsim_debug("latency_tag_dis request for cport: %04x\n",
 			    le16toh(setup->wValue));
 		break;
+	case GB_APB_REQUEST_ARPC_RUN:
+		arpc_response_send(setup);
+		break;
 	default:
 		gbsim_error("Invalid request type %02x\n", setup->bRequest);
 	}