The switch has registers which are useful for debugging issues:
* Trace registers
This can be helpful to trace why packets have been filtered or dropped or if
there any other serious problems.
* Memory registers
These registers provide the current switch internal RAM
utilization. Especially a unexpected workload with an not appropriate queue
setup packets might be dropped due to memory exhaustion.
Expose that registers via debugfs.
Signed-off-by: Kurt Kanzenbach <kurt@xxxxxxxxxxxxx>
---
drivers/net/dsa/hirschmann/hellcreek.c | 207 ++++++++++++++++++++++++-
drivers/net/dsa/hirschmann/hellcreek.h | 1 +
2 files changed, 205 insertions(+), 3 deletions(-)
diff --git a/drivers/net/dsa/hirschmann/hellcreek.c b/drivers/net/dsa/hirschmann/hellcreek.c
index 7e678b298f99..a56df65ae486 100644
--- a/drivers/net/dsa/hirschmann/hellcreek.c
+++ b/drivers/net/dsa/hirschmann/hellcreek.c
@@ -23,6 +23,7 @@
#include <linux/delay.h>
#include <linux/ktime.h>
#include <linux/time.h>
+#include <linux/debugfs.h>
#include <net/dsa.h>
#include <net/pkt_sched.h>
@@ -1371,6 +1372,195 @@ static int hellcreek_port_setup_tc(struct dsa_switch *ds, int port,
return hellcreek_port_del_schedule(ds, port);
}
+static ssize_t hellcreek_dbg_swtrc_cfg_write(struct file *filp,
+ const char __user *buffer,
+ size_t count, loff_t *ppos)
+{
+ struct hellcreek *hellcreek = filp->private_data;
+ int ret;
+ u16 reg;
+
+ ret = kstrtou16_from_user(buffer, count, 16, ®);
+ if (ret)
+ return ret;
+
+ hellcreek_write(hellcreek, reg, HR_SWTRC_CFG);
+
+ return count;
+}
+
+static ssize_t hellcreek_dbg_swtrc0_write(struct file *filp,
+ const char __user *buffer,
+ size_t count, loff_t *ppos)
+{
+ struct hellcreek *hellcreek = filp->private_data;
+ int ret;
+ u16 reg;
+
+ ret = kstrtou16_from_user(buffer, count, 16, ®);
+ if (ret)
+ return ret;
+
+ hellcreek_write(hellcreek, reg, HR_SWTRC0);
+
+ return count;
+}
+
+static ssize_t hellcreek_dbg_swtrc1_write(struct file *filp,
+ const char __user *buffer,
+ size_t count, loff_t *ppos)
+{
+ struct hellcreek *hellcreek = filp->private_data;
+ int ret;
+ u16 reg;
+
+ ret = kstrtou16_from_user(buffer, count, 16, ®);
+ if (ret)
+ return ret;
+
+ hellcreek_write(hellcreek, reg, HR_SWTRC1);
+
+ return count;
+}
+
+static ssize_t hellcreek_dbg_swtrc0_read(struct file *filp,
+ char __user *buffer,
+ size_t count, loff_t *ppos)
+{
+ struct hellcreek *hellcreek = filp->private_data;
+ char buf[32];
+ ssize_t desc = 0;
+ u16 reg;
+
+ reg = hellcreek_read(hellcreek, HR_SWTRC0);
+
+ desc += snprintf(buf, sizeof(buf), "0x%04x\n", reg);
+
+ return simple_read_from_buffer(buffer, count, ppos, buf, desc);
+}
+
+static ssize_t hellcreek_dbg_swtrc1_read(struct file *filp,
+ char __user *buffer,
+ size_t count, loff_t *ppos)
+{
+ struct hellcreek *hellcreek = filp->private_data;
+ char buf[32];
+ ssize_t desc = 0;
+ u16 reg;
+
+ reg = hellcreek_read(hellcreek, HR_SWTRC1);
+
+ desc += snprintf(buf, sizeof(buf), "0x%04x\n", reg);
+
+ return simple_read_from_buffer(buffer, count, ppos, buf, desc);
+}
+
+static ssize_t hellcreek_dbg_mfree_read(struct file *filp,
+ char __user *buffer,
+ size_t count, loff_t *ppos)
+{
+ struct hellcreek *hellcreek = filp->private_data;
+ char buf[32];
+ ssize_t desc = 0;
+ u16 reg;
+
+ reg = hellcreek_read(hellcreek, HR_MFREE);
+
+ desc += snprintf(buf, sizeof(buf), "0x%04x\n", reg);
+
+ return simple_read_from_buffer(buffer, count, ppos, buf, desc);
+}
+
+static ssize_t hellcreek_dbg_pfree_read(struct file *filp,
+ char __user *buffer,
+ size_t count, loff_t *ppos)
+{
+ struct hellcreek *hellcreek = filp->private_data;
+ char buf[32];
+ ssize_t desc = 0;
+ u16 reg;
+
+ reg = hellcreek_read(hellcreek, HR_PFREE);
+
+ desc += snprintf(buf, sizeof(buf), "0x%04x\n", reg);
+
+ return simple_read_from_buffer(buffer, count, ppos, buf, desc);
+}
+
+static const struct file_operations hellcreek_dbg_swtrc_cfg_fops = {
+ .owner = THIS_MODULE,
+ .open = simple_open,
+ .write = hellcreek_dbg_swtrc_cfg_write,
+};
+
+static const struct file_operations hellcreek_dbg_swtrc0_fops = {
+ .owner = THIS_MODULE,
+ .open = simple_open,
+ .read = hellcreek_dbg_swtrc0_read,
+ .write = hellcreek_dbg_swtrc0_write,
+};
+
+static const struct file_operations hellcreek_dbg_swtrc1_fops = {
+ .owner = THIS_MODULE,
+ .open = simple_open,
+ .read = hellcreek_dbg_swtrc1_read,
+ .write = hellcreek_dbg_swtrc1_write,
+};
+
+static const struct file_operations hellcreek_dbg_pfree_fops = {
+ .owner = THIS_MODULE,
+ .open = simple_open,
+ .read = hellcreek_dbg_pfree_read,
+};
+
+static const struct file_operations hellcreek_dbg_mfree_fops = {
+ .owner = THIS_MODULE,
+ .open = simple_open,
+ .read = hellcreek_dbg_mfree_read,
+};
+
+static int hellcreek_debugfs_init(struct hellcreek *hellcreek)
+{
+ struct dentry *file;
+
+ hellcreek->debug_dir = debugfs_create_dir(dev_name(hellcreek->dev),
+ NULL);
+ if (!hellcreek->debug_dir)
+ return -ENOMEM;
+
+ file = debugfs_create_file("swtrc_cfg", 0200, hellcreek->debug_dir,
+ hellcreek, &hellcreek_dbg_swtrc_cfg_fops);
+ if (!file)
+ return -ENOMEM;
+
+ file = debugfs_create_file("swtrc0", 0600, hellcreek->debug_dir,
+ hellcreek, &hellcreek_dbg_swtrc0_fops);
+ if (!file)
+ return -ENOMEM;
+
+ file = debugfs_create_file("swtrc1", 0600, hellcreek->debug_dir,
+ hellcreek, &hellcreek_dbg_swtrc1_fops);
+ if (!file)
+ return -ENOMEM;
+
+ file = debugfs_create_file("pfree", 0400, hellcreek->debug_dir,
+ hellcreek, &hellcreek_dbg_pfree_fops);
+ if (!file)
+ return -ENOMEM;
+
+ file = debugfs_create_file("mfree", 0400, hellcreek->debug_dir,
+ hellcreek, &hellcreek_dbg_mfree_fops);
+ if (!file)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static void hellcreek_debugfs_exit(struct hellcreek *hellcreek)
+{
+ debugfs_remove_recursive(hellcreek->debug_dir);
+}
+
static const struct dsa_switch_ops hellcreek_ds_ops = {
.get_tag_protocol = hellcreek_get_tag_protocol,
.setup = hellcreek_setup,
@@ -1475,9 +1665,17 @@ static int hellcreek_probe(struct platform_device *pdev)
hellcreek_feature_detect(hellcreek);
+ ret = hellcreek_debugfs_init(hellcreek);
+ if (ret) {
+ dev_err(dev, "Failed to initialize debugfs!\n");
+ goto err_debugfs;
+ }
+
hellcreek->ds = devm_kzalloc(dev, sizeof(*hellcreek->ds), GFP_KERNEL);
- if (!hellcreek->ds)
- return -ENOMEM;
+ if (!hellcreek->ds) {
+ ret = -ENOMEM;
+ goto err_debugfs;
+ }
hellcreek->ds->dev = dev;
hellcreek->ds->priv = hellcreek;
@@ -1488,7 +1686,7 @@ static int hellcreek_probe(struct platform_device *pdev)
ret = dsa_register_switch(hellcreek->ds);
if (ret) {
dev_err(dev, "Unable to register switch\n");
- return ret;
+ goto err_debugfs;
}
ret = hellcreek_ptp_setup(hellcreek);
@@ -1511,6 +1709,8 @@ static int hellcreek_probe(struct platform_device *pdev)
hellcreek_ptp_free(hellcreek);
err_ptp_setup:
dsa_unregister_switch(hellcreek->ds);
+err_debugfs:
+ hellcreek_debugfs_exit(hellcreek);
return ret;
}
@@ -1519,6 +1719,7 @@ static int hellcreek_remove(struct platform_device *pdev)
{
struct hellcreek *hellcreek = platform_get_drvdata(pdev);
+ hellcreek_debugfs_exit(hellcreek);
hellcreek_hwtstamp_free(hellcreek);
hellcreek_ptp_free(hellcreek);
dsa_unregister_switch(hellcreek->ds);
diff --git a/drivers/net/dsa/hirschmann/hellcreek.h b/drivers/net/dsa/hirschmann/hellcreek.h
index d3d1a1144857..59cc7b59ff2c 100644
--- a/drivers/net/dsa/hirschmann/hellcreek.h
+++ b/drivers/net/dsa/hirschmann/hellcreek.h
@@ -280,6 +280,7 @@ struct hellcreek {
struct ptp_clock_info ptp_clock_info;
struct hellcreek_port ports[4];
struct delayed_work overflow_work;
+ struct dentry *debug_dir;
spinlock_t reg_lock; /* Switch IP register lock */
spinlock_t ptp_lock; /* PTP IP register lock */
void __iomem *base;
--
2.20.1
