[RFC 4/4] samples/rpmsg: add the imx pingpong rpmsg sample

Richard Zhu
2016-01-06T08:25:25Z

From: Richard Zhu <Richard.Zhu@freescale.com>

Add one pingpong rpmsg sample, that demostrate the
how to communicate with an AMP-configured remote
processor over rpmsg bus.

In this sample, A# core of imx AMP SOC would
send out one unsigned int data "rpmsg_pingpong",
the initialized value is "0",
to the remote M# core when this driver is loaded.

The "rpmsg_pingpong" would be plus one at M# core side,
then sent back to A# core.
A# would do the same operations, after receive the
"rpmsg_pingpong" sent out by M# core, then send it
back to M#.

The demonstration would be stopped after 10000 times

Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
---
samples/Kconfig | 8 +++
samples/rpmsg/Makefile | 1 +
samples/rpmsg/imx_rpmsg_pingpong.c | 99 ++++++++++++++++++++++++++++++++++++++
3 files changed, 108 insertions(+)
create mode 100644 samples/rpmsg/imx_rpmsg_pingpong.c

diff --git a/samples/Kconfig b/samples/Kconfig
index d54f28c..49e0b62 100644
--- a/samples/Kconfig
+++ b/samples/Kconfig
@@ -63,6 +63,14 @@ config SAMPLE_RPMSG_CLIENT
to communicate with an AMP-configured remote processor over
the rpmsg bus.

+config IMX_RPMSG_PINGPONG
+ tristate "Build imx rpmsg pingpong sample -- loadable modules only"
+ depends on RPMSG && m
+ help
+ Build an imx rpmsg pingpong sample driver, which demonstrates
+ the data transactions on the AMP-configured imx processor over
+ the rpmsg bus.
+
config SAMPLE_LIVEPATCH
tristate "Build live patching sample -- loadable modules only"
depends on LIVEPATCH && m
diff --git a/samples/rpmsg/Makefile b/samples/rpmsg/Makefile
index 2d4973c..c01daae 100644
--- a/samples/rpmsg/Makefile
+++ b/samples/rpmsg/Makefile
@@ -1 +1,2 @@
obj-$(CONFIG_SAMPLE_RPMSG_CLIENT) += rpmsg_client_sample.o
+obj-$(CONFIG_IMX_RPMSG_PINGPONG) += imx_rpmsg_pingpong.o
diff --git a/samples/rpmsg/imx_rpmsg_pingpong.c b/samples/rpmsg/imx_rpmsg_pingpong.c
new file mode 100644
index 0000000..f46ebe1
--- /dev/null
+++ b/samples/rpmsg/imx_rpmsg_pingpong.c
@@ -0,0 +1,99 @@
+/*
+ * Copyright (C) 2016 Freescale Semiconductor, Inc.
+ *
+ * derived from the omap-rpmsg implementation.
+ * Remote processor messaging transport - pingpong driver
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/virtio.h>
+#include <linux/rpmsg.h>
+
+#define MSG_LIMIT 100000
+static unsigned int rpmsg_pingpong;
+static int rx_count;
+
+static void rpmsg_pingpong_cb(struct rpmsg_channel *rpdev, void *data, int len,
+ void *priv, u32 src)
+{
+ int err;
+
+ /* reply */
+ rpmsg_pingpong = *(unsigned int *)data;
+ pr_info("get %d (src: 0x%x)\n",
+ rpmsg_pingpong, src);
+ rx_count++;
+
+ /* pingpongs should not live forever */
+ if (rx_count >= MSG_LIMIT) {
+ dev_info(&rpdev->dev, "goodbye!\n");
+ return;
+ }
+ rpmsg_pingpong++;
+ err = rpmsg_sendto(rpdev, (void *)(&rpmsg_pingpong), 4, src);
+
+ if (err)
+ dev_err(&rpdev->dev, "rpmsg_send failed: %d\n", err);
+}
+
+static int rpmsg_pingpong_probe(struct rpmsg_channel *rpdev)
+{
+ int err;
+
+ dev_info(&rpdev->dev, "new channel: 0x%x -> 0x%x!\n",
+ rpdev->src, rpdev->dst);
+
+ rpmsg_pingpong = 0;
+ rx_count = 0;
+ err = rpmsg_sendto(rpdev, (void *)(&rpmsg_pingpong), 4, rpdev->dst);
+ if (err) {
+ dev_err(&rpdev->dev, "rpmsg_send failed: %d\n", err);
+ return err;
+ }
+
+ return 0;
+}
+
+static void rpmsg_pingpong_remove(struct rpmsg_channel *rpdev)
+{
+ dev_info(&rpdev->dev, "rpmsg pingpong driver is removed\n");
+}
+
+static struct rpmsg_device_id rpmsg_driver_pingpong_id_table[] = {
+ { .name = "rpmsg-openamp-demo-channel" },
+ { },
+};
+MODULE_DEVICE_TABLE(rpmsg, rpmsg_driver_pingpong_id_table);
+
+static struct rpmsg_driver rpmsg_pingpong_driver = {
+ .drv.name = KBUILD_MODNAME,
+ .drv.owner = THIS_MODULE,
+ .id_table = rpmsg_driver_pingpong_id_table,
+ .probe = rpmsg_pingpong_probe,
+ .callback = rpmsg_pingpong_cb,
+ .remove = rpmsg_pingpong_remove,
+};
+
+static int __init init(void)
+{
+ return register_rpmsg_driver(&rpmsg_pingpong_driver);
+}
+
+static void __exit fini(void)
+{
+ unregister_rpmsg_driver(&rpmsg_pingpong_driver);
+}
+module_init(init);
+module_exit(fini);
+
+MODULE_AUTHOR("Freescale Semiconductor, Inc.");
+MODULE_DESCRIPTION("iMX virtio remote processor messaging pingpong driver");
+MODULE_LICENSE("GPL v2");
--
1.9.1