net: ethernet: mtk_eth_soc: support per-flow accounting on MT7988

NETSYS_V3 uses 64 bits for each counters while older SoCs are using
48/40 bits for each counter.
Support reading per-flow byte and package counters on NETSYS_V3.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/37a0928fa8c1253b197884c68ce1f54239421ac5.1690946442.git.daniel@makrotopia.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

drivers/net/ethernet/mediatek/mtk_eth_soc.c

@@ -5064,6 +5064,7 @@ static const struct mtk_soc_data mt7988_data = {
 	.version = 3,
 	.offload_version = 2,
 	.hash_offset = 4,
+	.has_accounting = true,
 	.foe_entry_size = MTK_FOE_ENTRY_V3_SIZE,
 	.txrx = {
 		.txd_size = sizeof(struct mtk_tx_dma_v2),

drivers/net/ethernet/mediatek/mtk_ppe.c

@@ -92,7 +92,6 @@ static int mtk_ppe_mib_wait_busy(struct mtk_ppe *ppe)
 
 static int mtk_mib_entry_read(struct mtk_ppe *ppe, u16 index, u64 *bytes, u64 *packets)
 {
-	u32 byte_cnt_low, byte_cnt_high, pkt_cnt_low, pkt_cnt_high;
 	u32 val, cnt_r0, cnt_r1, cnt_r2;
 	int ret;
 
@@ -107,12 +106,20 @@ static int mtk_mib_entry_read(struct mtk_ppe *ppe, u16 index, u64 *bytes, u64 *p
 	cnt_r1 = readl(ppe->base + MTK_PPE_MIB_SER_R1);
 	cnt_r2 = readl(ppe->base + MTK_PPE_MIB_SER_R2);
 
-	byte_cnt_low = FIELD_GET(MTK_PPE_MIB_SER_R0_BYTE_CNT_LOW, cnt_r0);
-	byte_cnt_high = FIELD_GET(MTK_PPE_MIB_SER_R1_BYTE_CNT_HIGH, cnt_r1);
-	pkt_cnt_low = FIELD_GET(MTK_PPE_MIB_SER_R1_PKT_CNT_LOW, cnt_r1);
-	pkt_cnt_high = FIELD_GET(MTK_PPE_MIB_SER_R2_PKT_CNT_HIGH, cnt_r2);
-	*bytes = ((u64)byte_cnt_high << 32) | byte_cnt_low;
-	*packets = (pkt_cnt_high << 16) | pkt_cnt_low;
+	if (mtk_is_netsys_v3_or_greater(ppe->eth)) {
+		/* 64 bit for each counter */
+		u32 cnt_r3 = readl(ppe->base + MTK_PPE_MIB_SER_R3);
+		*bytes = ((u64)cnt_r1 << 32) | cnt_r0;
+		*packets = ((u64)cnt_r3 << 32) | cnt_r2;
+	} else {
+		/* 48 bit byte counter, 40 bit packet counter */
+		u32 byte_cnt_low = FIELD_GET(MTK_PPE_MIB_SER_R0_BYTE_CNT_LOW, cnt_r0);
+		u32 byte_cnt_high = FIELD_GET(MTK_PPE_MIB_SER_R1_BYTE_CNT_HIGH, cnt_r1);
+		u32 pkt_cnt_low = FIELD_GET(MTK_PPE_MIB_SER_R1_PKT_CNT_LOW, cnt_r1);
+		u32 pkt_cnt_high = FIELD_GET(MTK_PPE_MIB_SER_R2_PKT_CNT_HIGH, cnt_r2);
+		*bytes = ((u64)byte_cnt_high << 32) | byte_cnt_low;
+		*packets = ((u64)pkt_cnt_high << 16) | pkt_cnt_low;
+	}
 
 	return 0;
 }

drivers/net/ethernet/mediatek/mtk_ppe_regs.h

@@ -163,6 +163,8 @@ enum {
 #define MTK_PPE_MIB_SER_R2			0x348
 #define MTK_PPE_MIB_SER_R2_PKT_CNT_HIGH		GENMASK(23, 0)
 
+#define MTK_PPE_MIB_SER_R3			0x34c
+
 #define MTK_PPE_MIB_CACHE_CTL			0x350
 #define MTK_PPE_MIB_CACHE_CTL_EN		BIT(0)
 #define MTK_PPE_MIB_CACHE_CTL_FLUSH		BIT(2)