[PATCH v2 2/2] firmware: imx: sm-misc: Dump syslog info

Peng Fan
2025-10-11T11:34:21Z

Add debugfs interface to read System Manager syslog info

Signed-off-by: Peng Fan <peng.fan@nxp.com>
---
drivers/firmware/imx/sm-misc.c | 38 +++++++++++++++++++++++++++++++++++++-
1 file changed, 37 insertions(+), 1 deletion(-)

diff --git a/drivers/firmware/imx/sm-misc.c b/drivers/firmware/imx/sm-misc.c
index fc3ee12c2be878e0285183e3381c9514a63d5142..d99b9420277ed11b297234acb62a6e695576c844 100644
--- a/drivers/firmware/imx/sm-misc.c
+++ b/drivers/firmware/imx/sm-misc.c
@@ -3,12 +3,16 @@
* Copyright 2024 NXP
*/

+#include <linux/debugfs.h>
+#include <linux/device/devres.h>
#include <linux/firmware/imx/sm.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/scmi_protocol.h>
#include <linux/scmi_imx_protocol.h>
+#include <linux/seq_file.h>
+#include <linux/sizes.h>

static const struct scmi_imx_misc_proto_ops *imx_misc_ctrl_ops;
static struct scmi_protocol_handle *ph;
@@ -44,10 +48,39 @@ static int scmi_imx_misc_ctrl_notifier(struct notifier_block *nb,
return 0;
}

+static int syslog_show(struct seq_file *file, void *priv)
+{
+ /* 4KB is large enough for syslog */
+ void *syslog __free(kfree) = kmalloc(SZ_4K, GFP_KERNEL);
+ struct device *dev = file->private;
+ /* syslog API use num words, not num bytes */
+ u16 size = SZ_4K / 4;
+ int ret;
+
+ if (!ph)
+ return -ENODEV;
+
+ ret = imx_misc_ctrl_ops->misc_syslog(ph, &size, syslog);
+ if (ret)
+ return ret;
+
+ seq_hex_dump(file, " ", DUMP_PREFIX_NONE, 16, sizeof(u32), syslog, size * 4, false);
+ seq_putc(file, '\n');
+
+ return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(syslog);
+
+static void scmi_imx_misc_put(void *p)
+{
+ debugfs_remove((struct dentry *)p);
+}
+
static int scmi_imx_misc_ctrl_probe(struct scmi_device *sdev)
{
const struct scmi_handle *handle = sdev->handle;
struct device_node *np = sdev->dev.of_node;
+ struct dentry *scmi_imx_dentry;
u32 src_id, flags;
int ret, i, num;

@@ -98,7 +131,10 @@ static int scmi_imx_misc_ctrl_probe(struct scmi_device *sdev)
}
}

- return 0;
+ scmi_imx_dentry = debugfs_create_dir("scmi_imx", NULL);
+ debugfs_create_file("syslog", 0444, scmi_imx_dentry, &sdev->dev, &syslog_fops);
+
+ return devm_add_action_or_reset(&sdev->dev, scmi_imx_misc_put, scmi_imx_dentry);
}

static const struct scmi_device_id scmi_id_table[] = {

--
2.37.1