net: airoha: Add FLOW_CLS_STATS callback support

Introduce per-flow stats accounting to the flowtable hw offload in
the airoha_eth driver. Flow stats are split in the PPE and NPU modules:
- PPE: accounts for high 32bit of per-flow stats
- NPU: accounts for low 32bit of per-flow stats

FLOW_CLS_STATS can be enabled or disabled at compile time.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250516-airoha-en7581-flowstats-v2-2-06d5fbf28984@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: LorenzoBianconi

drivers/net/ethernet/airoha/Kconfig

@@ -24,4 +24,11 @@ config NET_AIROHA
 	  This driver supports the gigabit ethernet MACs in the
 	  Airoha SoC family.
 
+config NET_AIROHA_FLOW_STATS
+	default y
+	bool "Airoha flow stats"
+	depends on NET_AIROHA && NET_AIROHA_NPU
+	help
+	  Enable Aiorha flowtable statistic counters.
+
 endif #NET_VENDOR_AIROHA

drivers/net/ethernet/airoha/airoha_eth.h

@@ -50,6 +50,14 @@
 #define PPE_NUM				2
 #define PPE1_SRAM_NUM_ENTRIES		(8 * 1024)
 #define PPE_SRAM_NUM_ENTRIES		(2 * PPE1_SRAM_NUM_ENTRIES)
+#ifdef CONFIG_NET_AIROHA_FLOW_STATS
+#define PPE1_STATS_NUM_ENTRIES		(4 * 1024)
+#else
+#define PPE1_STATS_NUM_ENTRIES		0
+#endif /* CONFIG_NET_AIROHA_FLOW_STATS */
+#define PPE_STATS_NUM_ENTRIES		(2 * PPE1_STATS_NUM_ENTRIES)
+#define PPE1_SRAM_NUM_DATA_ENTRIES	(PPE1_SRAM_NUM_ENTRIES - PPE1_STATS_NUM_ENTRIES)
+#define PPE_SRAM_NUM_DATA_ENTRIES	(2 * PPE1_SRAM_NUM_DATA_ENTRIES)
 #define PPE_DRAM_NUM_ENTRIES		(16 * 1024)
 #define PPE_NUM_ENTRIES			(PPE_SRAM_NUM_ENTRIES + PPE_DRAM_NUM_ENTRIES)
 #define PPE_HASH_MASK			(PPE_NUM_ENTRIES - 1)
@@ -261,6 +269,8 @@ struct airoha_foe_mac_info {
 
 	u16 pppoe_id;
 	u16 src_mac_lo;
+
+	u32 meter;
 };
 
 #define AIROHA_FOE_IB1_UNBIND_PREBIND		BIT(24)
@@ -296,6 +306,11 @@ struct airoha_foe_mac_info {
 #define AIROHA_FOE_TUNNEL			BIT(6)
 #define AIROHA_FOE_TUNNEL_ID			GENMASK(5, 0)
 
+#define AIROHA_FOE_TUNNEL_MTU			GENMASK(31, 16)
+#define AIROHA_FOE_ACNT_GRP3			GENMASK(15, 9)
+#define AIROHA_FOE_METER_GRP3			GENMASK(8, 5)
+#define AIROHA_FOE_METER_GRP2			GENMASK(4, 0)
+
 struct airoha_foe_bridge {
 	u32 dest_mac_hi;
 
@@ -379,6 +394,8 @@ struct airoha_foe_ipv6 {
 	u32 ib2;
 
 	struct airoha_foe_mac_info_common l2;
+
+	u32 meter;
 };
 
 struct airoha_foe_entry {
@@ -397,6 +414,16 @@ struct airoha_foe_entry {
 	};
 };
 
+struct airoha_foe_stats {
+	u32 bytes;
+	u32 packets;
+};
+
+struct airoha_foe_stats64 {
+	u64 bytes;
+	u64 packets;
+};
+
 struct airoha_flow_data {
 	struct ethhdr eth;
 
@@ -447,6 +474,7 @@ struct airoha_flow_table_entry {
 	struct hlist_node l2_subflow_node; /* PPE L2 subflow entry */
 	u32 hash;
 
+	struct airoha_foe_stats64 stats;
 	enum airoha_flow_entry_type type;
 
 	struct rhash_head node;
@@ -523,6 +551,9 @@ struct airoha_ppe {
 	struct hlist_head *foe_flow;
 	u16 foe_check_time[PPE_NUM_ENTRIES];
 
+	struct airoha_foe_stats *foe_stats;
+	dma_addr_t foe_stats_dma;
+
 	struct dentry *debugfs_dir;
 };
 
@@ -582,6 +613,8 @@ int airoha_ppe_init(struct airoha_eth *eth);
 void airoha_ppe_deinit(struct airoha_eth *eth);
 struct airoha_foe_entry *airoha_ppe_foe_get_entry(struct airoha_ppe *ppe,
 						  u32 hash);
+void airoha_ppe_foe_entry_get_stats(struct airoha_ppe *ppe, u32 hash,
+				    struct airoha_foe_stats64 *stats);
 
 #ifdef CONFIG_DEBUG_FS
 int airoha_ppe_debugfs_init(struct airoha_ppe *ppe);

drivers/net/ethernet/airoha/airoha_npu.c

@@ -12,6 +12,7 @@
 #include <linux/of_reserved_mem.h>
 #include <linux/regmap.h>
 
+#include "airoha_eth.h"
 #include "airoha_npu.h"
 
 #define NPU_EN7581_FIRMWARE_DATA		"airoha/en7581_npu_data.bin"
@@ -72,6 +73,7 @@ enum {
 	PPE_FUNC_SET_WAIT_HWNAT_INIT,
 	PPE_FUNC_SET_WAIT_HWNAT_DEINIT,
 	PPE_FUNC_SET_WAIT_API,
+	PPE_FUNC_SET_WAIT_FLOW_STATS_SETUP,
 };
 
 enum {
@@ -115,6 +117,10 @@ struct ppe_mbox_data {
 			u32 size;
 			u32 data;
 		} set_info;
+		struct {
+			u32 npu_stats_addr;
+			u32 foe_stats_addr;
+		} stats_info;
 	};
 };
 
@@ -351,7 +357,40 @@ static int airoha_npu_foe_commit_entry(struct airoha_npu *npu,
 	return err;
 }
 
-struct airoha_npu *airoha_npu_get(struct device *dev)
+static int airoha_npu_stats_setup(struct airoha_npu *npu,
+				  dma_addr_t foe_stats_addr)
+{
+	int err, size = PPE_STATS_NUM_ENTRIES * sizeof(*npu->stats);
+	struct ppe_mbox_data *ppe_data;
+
+	if (!size) /* flow stats are disabled */
+		return 0;
+
+	ppe_data = kzalloc(sizeof(*ppe_data), GFP_ATOMIC);
+	if (!ppe_data)
+		return -ENOMEM;
+
+	ppe_data->func_type = NPU_OP_SET;
+	ppe_data->func_id = PPE_FUNC_SET_WAIT_FLOW_STATS_SETUP;
+	ppe_data->stats_info.foe_stats_addr = foe_stats_addr;
+
+	err = airoha_npu_send_msg(npu, NPU_FUNC_PPE, ppe_data,
+				  sizeof(*ppe_data));
+	if (err)
+		goto out;
+
+	npu->stats = devm_ioremap(npu->dev,
+				  ppe_data->stats_info.npu_stats_addr,
+				  size);
+	if (!npu->stats)
+		err = -ENOMEM;
+out:
+	kfree(ppe_data);
+
+	return err;
+}
+
+struct airoha_npu *airoha_npu_get(struct device *dev, dma_addr_t *stats_addr)
 {
 	struct platform_device *pdev;
 	struct device_node *np;
@@ -389,6 +428,17 @@ struct airoha_npu *airoha_npu_get(struct device *dev)
 		goto error_module_put;
 	}
 
+	if (stats_addr) {
+		int err;
+
+		err = airoha_npu_stats_setup(npu, *stats_addr);
+		if (err) {
+			dev_err(dev, "failed to allocate npu stats buffer\n");
+			npu = ERR_PTR(err);
+			goto error_module_put;
+		}
+	}
+
 	return npu;
 
 error_module_put:

drivers/net/ethernet/airoha/airoha_npu.h

@@ -17,6 +17,8 @@ struct airoha_npu {
 		struct work_struct wdt_work;
 	} cores[NPU_NUM_CORES];
 
+	struct airoha_foe_stats __iomem *stats;
+
 	struct {
 		int (*ppe_init)(struct airoha_npu *npu);
 		int (*ppe_deinit)(struct airoha_npu *npu);
@@ -30,5 +32,5 @@ struct airoha_npu {
 	} ops;
 };
 
-struct airoha_npu *airoha_npu_get(struct device *dev);
+struct airoha_npu *airoha_npu_get(struct device *dev, dma_addr_t *stats_addr);
 void airoha_npu_put(struct airoha_npu *npu);