net: ethernet: qualcomm: Add PPE debugfs support for PPE counters

The PPE hardware counters maintain counters for packets handled by the
various functional blocks of PPE. They help in tracing the packets
passed through PPE and debugging any packet drops.

The counters displayed by this debugfs file are ones that are common
for all Ethernet ports, and they do not include the counters that are
specific for a MAC port. Hence they cannot be displayed using ethtool.
The per-MAC counters will be supported using "ethtool -S" along with
the netdevice driver.

The PPE hardware various type counters are made available through the
debugfs files under directory "/sys/kernel/debug/ppe/".

Signed-off-by: Luo Jie <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Paolo Abeni <[email protected]>

Author: Luo Jie

drivers/net/ethernet/qualcomm/ppe/Makefile

@@ -4,4 +4,4 @@
 #
 
 obj-$(CONFIG_QCOM_PPE) += qcom-ppe.o
-qcom-ppe-objs := ppe.o ppe_config.o
+qcom-ppe-objs := ppe.o ppe_config.o ppe_debugfs.o

drivers/net/ethernet/qualcomm/ppe/ppe.c

@@ -16,6 +16,7 @@
 
 #include "ppe.h"
 #include "ppe_config.h"
+#include "ppe_debugfs.h"
 
 #define PPE_PORT_MAX		8
 #define PPE_CLK_RATE		353000000
@@ -204,11 +205,20 @@ static int qcom_ppe_probe(struct platform_device *pdev)
 	if (ret)
 		return dev_err_probe(dev, ret, "PPE HW config failed\n");
 
+	ppe_debugfs_setup(ppe_dev);
 	platform_set_drvdata(pdev, ppe_dev);
 
 	return 0;
 }
 
+static void qcom_ppe_remove(struct platform_device *pdev)
+{
+	struct ppe_device *ppe_dev;
+
+	ppe_dev = platform_get_drvdata(pdev);
+	ppe_debugfs_teardown(ppe_dev);
+}
+
 static const struct of_device_id qcom_ppe_of_match[] = {
 	{ .compatible = "qcom,ipq9574-ppe" },
 	{}
@@ -221,6 +231,7 @@ static struct platform_driver qcom_ppe_driver = {
 		.of_match_table = qcom_ppe_of_match,
 	},
 	.probe	= qcom_ppe_probe,
+	.remove = qcom_ppe_remove,
 };
 module_platform_driver(qcom_ppe_driver);
 

drivers/net/ethernet/qualcomm/ppe/ppe.h

@@ -11,13 +11,15 @@
 
 struct device;
 struct regmap;
+struct dentry;
 
 /**
  * struct ppe_device - PPE device private data.
  * @dev: PPE device structure.
  * @regmap: PPE register map.
  * @clk_rate: PPE clock rate.
  * @num_ports: Number of PPE ports.
+ * @debugfs_root: Debugfs root entry.
  * @num_icc_paths: Number of interconnect paths.
  * @icc_paths: Interconnect path array.
  *
@@ -30,6 +32,7 @@ struct ppe_device {
 	struct regmap *regmap;
 	unsigned long clk_rate;
 	unsigned int num_ports;
+	struct dentry *debugfs_root;
 	unsigned int num_icc_paths;
 	struct icc_bulk_data icc_paths[] __counted_by(num_icc_paths);
 };