mediatek: add patches for MT7622 WED (wireless ethernet dispatch)

This series also contains other improvement for hardware flow offload support

Signed-off-by: Felix Fietkau <nbd@nbd.name>
(cherry-picked from commit 0f029b3d2b505b40aca9a24a002838ed1060f83d)

1 files changed, 424 insertions, 0 deletions

diff --git a/target/linux/generic/pending-5.10/701-08-net-ethernet-mtk_eth_soc-rework-hardware-flow-table-.patch b/target/linux/generic/pending-5.10/701-08-net-ethernet-mtk_eth_soc-rework-hardware-flow-table-.patch
new file mode 100644
index 0000000000..ac67f8078c
--- /dev/null
+++ b/target/linux/generic/pending-5.10/701-08-net-ethernet-mtk_eth_soc-rework-hardware-flow-table-.patch
@@ -0,0 +1,424 @@
+From: Felix Fietkau <nbd@nbd.name>
+Date: Mon, 21 Feb 2022 15:39:18 +0100
+Subject: [PATCH] net: ethernet: mtk_eth_soc: rework hardware flow table
+ management
+
+The hardware was designed to handle flow detection and creation of flow entries
+by itself, relying on the software primarily for filling in egress routing
+information.
+When there is a hash collision between multiple flows, this allows the hardware
+to maintain the entry for the most active flow.
+Additionally, the hardware only keeps offloading active for entries with at
+least 30 packets per second.
+
+With this rework, the code no longer creates a hardware entries directly.
+Instead, the hardware entry is only created when the PPE reports a matching
+unbound flow with the minimum target rate.
+In order to reduce CPU overhead, looking for flows belonging to a hash entry
+is rate limited to once every 100ms.
+
+This rework is also used as preparation for emulating bridge offload by
+managing L4 offload entries on demand.
+
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+
+--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
++++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+@@ -21,6 +21,7 @@
+ #include <linux/pinctrl/devinfo.h>
+ #include <linux/phylink.h>
+ #include <linux/jhash.h>
++#include <linux/bitfield.h>
+ #include <net/dsa.h>
+ 
+ #include "mtk_eth_soc.h"
+@@ -1274,7 +1275,7 @@ static int mtk_poll_rx(struct napi_struc
+ 		struct net_device *netdev;
+ 		unsigned int pktlen;
+ 		dma_addr_t dma_addr;
+-		u32 hash;
++		u32 hash, reason;
+ 		int mac;
+ 
+ 		ring = mtk_get_rx_ring(eth);
+@@ -1350,6 +1351,11 @@ static int mtk_poll_rx(struct napi_struc
+ 			skb_set_hash(skb, hash, PKT_HASH_TYPE_L4);
+ 		}
+ 
++		reason = FIELD_GET(MTK_RXD4_PPE_CPU_REASON, trxd.rxd4);
++		if (reason == MTK_PPE_CPU_REASON_HIT_UNBIND_RATE_REACHED)
++			mtk_ppe_check_skb(eth->ppe, skb,
++					  trxd.rxd4 & MTK_RXD4_FOE_ENTRY);
++
+ 		if (netdev->features & NETIF_F_HW_VLAN_CTAG_RX &&
+ 		    (trxd.rxd2 & RX_DMA_VTAG))
+ 			__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
+@@ -3265,7 +3271,7 @@ static int mtk_probe(struct platform_dev
+ 	}
+ 
+ 	if (eth->soc->offload_version) {
+-		eth->ppe = mtk_ppe_init(eth->dev, eth->base + MTK_ETH_PPE_BASE, 2);
++		eth->ppe = mtk_ppe_init(eth, eth->base + MTK_ETH_PPE_BASE, 2);
+ 		if (!eth->ppe) {
+ 			err = -ENOMEM;
+ 			goto err_free_dev;
+--- a/drivers/net/ethernet/mediatek/mtk_ppe.c
++++ b/drivers/net/ethernet/mediatek/mtk_ppe.c
+@@ -6,9 +6,12 @@
+ #include <linux/iopoll.h>
+ #include <linux/etherdevice.h>
+ #include <linux/platform_device.h>
++#include "mtk_eth_soc.h"
+ #include "mtk_ppe.h"
+ #include "mtk_ppe_regs.h"
+ 
++static DEFINE_SPINLOCK(ppe_lock);
++
+ static void ppe_w32(struct mtk_ppe *ppe, u32 reg, u32 val)
+ {
+ 	writel(val, ppe->base + reg);
+@@ -41,6 +44,11 @@ static u32 ppe_clear(struct mtk_ppe *ppe
+ 	return ppe_m32(ppe, reg, val, 0);
+ }
+ 
++static u32 mtk_eth_timestamp(struct mtk_eth *eth)
++{
++	return mtk_r32(eth, 0x0010) & MTK_FOE_IB1_BIND_TIMESTAMP;
++}
++
+ static int mtk_ppe_wait_busy(struct mtk_ppe *ppe)
+ {
+ 	int ret;
+@@ -353,26 +361,59 @@ static inline bool mtk_foe_entry_usable(
+ 	       FIELD_GET(MTK_FOE_IB1_STATE, entry->ib1) != MTK_FOE_STATE_BIND;
+ }
+ 
+-int mtk_foe_entry_commit(struct mtk_ppe *ppe, struct mtk_foe_entry *entry,
+-			 u16 timestamp)
++static bool
++mtk_flow_entry_match(struct mtk_flow_entry *entry, struct mtk_foe_entry *data)
++{
++	int type, len;
++
++	if ((data->ib1 ^ entry->data.ib1) & MTK_FOE_IB1_UDP)
++		return false;
++
++	type = FIELD_GET(MTK_FOE_IB1_PACKET_TYPE, entry->data.ib1);
++	if (type > MTK_PPE_PKT_TYPE_IPV4_DSLITE)
++		len = offsetof(struct mtk_foe_entry, ipv6._rsv);
++	else
++		len = offsetof(struct mtk_foe_entry, ipv4.ib2);
++
++	return !memcmp(&entry->data.data, &data->data, len - 4);
++}
++
++static void
++mtk_flow_entry_update(struct mtk_ppe *ppe, struct mtk_flow_entry *entry)
+ {
+ 	struct mtk_foe_entry *hwe;
+-	u32 hash;
++	struct mtk_foe_entry foe;
+ 
++	spin_lock_bh(&ppe_lock);
++	if (entry->hash == 0xffff)
++		goto out;
++
++	hwe = &ppe->foe_table[entry->hash];
++	memcpy(&foe, hwe, sizeof(foe));
++	if (!mtk_flow_entry_match(entry, &foe)) {
++		entry->hash = 0xffff;
++		goto out;
++	}
++
++	entry->data.ib1 = foe.ib1;
++
++out:
++	spin_unlock_bh(&ppe_lock);
++}
++
++static void
++__mtk_foe_entry_commit(struct mtk_ppe *ppe, struct mtk_foe_entry *entry,
++		       u16 hash)
++{
++	struct mtk_foe_entry *hwe;
++	u16 timestamp;
++
++	timestamp = mtk_eth_timestamp(ppe->eth);
+ 	timestamp &= MTK_FOE_IB1_BIND_TIMESTAMP;
+ 	entry->ib1 &= ~MTK_FOE_IB1_BIND_TIMESTAMP;
+ 	entry->ib1 |= FIELD_PREP(MTK_FOE_IB1_BIND_TIMESTAMP, timestamp);
+ 
+-	hash = mtk_ppe_hash_entry(entry);
+ 	hwe = &ppe->foe_table[hash];
+-	if (!mtk_foe_entry_usable(hwe)) {
+-		hwe++;
+-		hash++;
+-
+-		if (!mtk_foe_entry_usable(hwe))
+-			return -ENOSPC;
+-	}
+-
+ 	memcpy(&hwe->data, &entry->data, sizeof(hwe->data));
+ 	wmb();
+ 	hwe->ib1 = entry->ib1;
+@@ -380,13 +421,77 @@ int mtk_foe_entry_commit(struct mtk_ppe
+ 	dma_wmb();
+ 
+ 	mtk_ppe_cache_clear(ppe);
++}
+ 
+-	return hash;
++void mtk_foe_entry_clear(struct mtk_ppe *ppe, struct mtk_flow_entry *entry)
++{
++	spin_lock_bh(&ppe_lock);
++	hlist_del_init(&entry->list);
++	if (entry->hash != 0xffff) {
++		ppe->foe_table[entry->hash].ib1 &= ~MTK_FOE_IB1_STATE;
++		ppe->foe_table[entry->hash].ib1 |= FIELD_PREP(MTK_FOE_IB1_STATE,
++							      MTK_FOE_STATE_BIND);
++		dma_wmb();
++	}
++	entry->hash = 0xffff;
++	spin_unlock_bh(&ppe_lock);
++}
++
++int mtk_foe_entry_commit(struct mtk_ppe *ppe, struct mtk_flow_entry *entry)
++{
++	u32 hash = mtk_ppe_hash_entry(&entry->data);
++
++	entry->hash = 0xffff;
++	spin_lock_bh(&ppe_lock);
++	hlist_add_head(&entry->list, &ppe->foe_flow[hash / 2]);
++	spin_unlock_bh(&ppe_lock);
++
++	return 0;
++}
++
++void __mtk_ppe_check_skb(struct mtk_ppe *ppe, struct sk_buff *skb, u16 hash)
++{
++	struct hlist_head *head = &ppe->foe_flow[hash / 2];
++	struct mtk_flow_entry *entry;
++	struct mtk_foe_entry *hwe = &ppe->foe_table[hash];
++	bool found = false;
++
++	if (hlist_empty(head))
++		return;
++
++	spin_lock_bh(&ppe_lock);
++	hlist_for_each_entry(entry, head, list) {
++		if (found || !mtk_flow_entry_match(entry, hwe)) {
++			if (entry->hash != 0xffff)
++				entry->hash = 0xffff;
++			continue;
++		}
++
++		entry->hash = hash;
++		__mtk_foe_entry_commit(ppe, &entry->data, hash);
++		found = true;
++	}
++	spin_unlock_bh(&ppe_lock);
++}
++
++int mtk_foe_entry_idle_time(struct mtk_ppe *ppe, struct mtk_flow_entry *entry)
++{
++	u16 now = mtk_eth_timestamp(ppe->eth) & MTK_FOE_IB1_BIND_TIMESTAMP;
++	u16 timestamp;
++
++	mtk_flow_entry_update(ppe, entry);
++	timestamp = entry->data.ib1 & MTK_FOE_IB1_BIND_TIMESTAMP;
++
++	if (timestamp > now)
++		return MTK_FOE_IB1_BIND_TIMESTAMP + 1 - timestamp + now;
++	else
++		return now - timestamp;
+ }
+ 
+-struct mtk_ppe *mtk_ppe_init(struct device *dev, void __iomem *base,
++struct mtk_ppe *mtk_ppe_init(struct mtk_eth *eth, void __iomem *base,
+ 		 int version)
+ {
++	struct device *dev = eth->dev;
+ 	struct mtk_foe_entry *foe;
+ 	struct mtk_ppe *ppe;
+ 
+@@ -398,6 +503,7 @@ struct mtk_ppe *mtk_ppe_init(struct devi
+ 	 * not coherent.
+ 	 */
+ 	ppe->base = base;
++	ppe->eth = eth;
+ 	ppe->dev = dev;
+ 	ppe->version = version;
+ 
+--- a/drivers/net/ethernet/mediatek/mtk_ppe.h
++++ b/drivers/net/ethernet/mediatek/mtk_ppe.h
+@@ -235,7 +235,17 @@ enum {
+ 	MTK_PPE_CPU_REASON_INVALID			= 0x1f,
+ };
+ 
++struct mtk_flow_entry {
++	struct rhash_head node;
++	struct hlist_node list;
++	unsigned long cookie;
++	struct mtk_foe_entry data;
++	u16 hash;
++	s8 wed_index;
++};
++
+ struct mtk_ppe {
++	struct mtk_eth *eth;
+ 	struct device *dev;
+ 	void __iomem *base;
+ 	int version;
+@@ -243,18 +253,33 @@ struct mtk_ppe {
+ 	struct mtk_foe_entry *foe_table;
+ 	dma_addr_t foe_phys;
+ 
++	u16 foe_check_time[MTK_PPE_ENTRIES];
++	struct hlist_head foe_flow[MTK_PPE_ENTRIES / 2];
++
+ 	void *acct_table;
+ };
+ 
+-struct mtk_ppe *mtk_ppe_init(struct device *dev, void __iomem *base, int version);
++struct mtk_ppe *mtk_ppe_init(struct mtk_eth *eth, void __iomem *base, int version);
+ int mtk_ppe_start(struct mtk_ppe *ppe);
+ int mtk_ppe_stop(struct mtk_ppe *ppe);
+ 
++void __mtk_ppe_check_skb(struct mtk_ppe *ppe, struct sk_buff *skb, u16 hash);
++
+ static inline void
+-mtk_foe_entry_clear(struct mtk_ppe *ppe, u16 hash)
++mtk_ppe_check_skb(struct mtk_ppe *ppe, struct sk_buff *skb, u16 hash)
+ {
+-	ppe->foe_table[hash].ib1 = 0;
+-	dma_wmb();
++	u16 now, diff;
++
++	if (!ppe)
++		return;
++
++	now = (u16)jiffies;
++	diff = now - ppe->foe_check_time[hash];
++	if (diff < HZ / 10)
++		return;
++
++	ppe->foe_check_time[hash] = now;
++	__mtk_ppe_check_skb(ppe, skb, hash);
+ }
+ 
+ static inline int
+@@ -282,8 +307,9 @@ int mtk_foe_entry_set_vlan(struct mtk_fo
+ int mtk_foe_entry_set_pppoe(struct mtk_foe_entry *entry, int sid);
+ int mtk_foe_entry_set_wdma(struct mtk_foe_entry *entry, int wdma_idx, int txq,
+ 			   int bss, int wcid);
+-int mtk_foe_entry_commit(struct mtk_ppe *ppe, struct mtk_foe_entry *entry,
+-			 u16 timestamp);
++int mtk_foe_entry_commit(struct mtk_ppe *ppe, struct mtk_flow_entry *entry);
++void mtk_foe_entry_clear(struct mtk_ppe *ppe, struct mtk_flow_entry *entry);
++int mtk_foe_entry_idle_time(struct mtk_ppe *ppe, struct mtk_flow_entry *entry);
+ int mtk_ppe_debugfs_init(struct mtk_ppe *ppe);
+ 
+ #endif
+--- a/drivers/net/ethernet/mediatek/mtk_ppe_offload.c
++++ b/drivers/net/ethernet/mediatek/mtk_ppe_offload.c
+@@ -43,13 +43,6 @@ struct mtk_flow_data {
+ 	} pppoe;
+ };
+ 
+-struct mtk_flow_entry {
+-	struct rhash_head node;
+-	unsigned long cookie;
+-	u16 hash;
+-	s8 wed_index;
+-};
+-
+ static const struct rhashtable_params mtk_flow_ht_params = {
+ 	.head_offset = offsetof(struct mtk_flow_entry, node),
+ 	.key_offset = offsetof(struct mtk_flow_entry, cookie),
+@@ -57,12 +50,6 @@ static const struct rhashtable_params mt
+ 	.automatic_shrinking = true,
+ };
+ 
+-static u32
+-mtk_eth_timestamp(struct mtk_eth *eth)
+-{
+-	return mtk_r32(eth, 0x0010) & MTK_FOE_IB1_BIND_TIMESTAMP;
+-}
+-
+ static int
+ mtk_flow_set_ipv4_addr(struct mtk_foe_entry *foe, struct mtk_flow_data *data,
+ 		       bool egress)
+@@ -238,10 +225,8 @@ mtk_flow_offload_replace(struct mtk_eth
+ 	int offload_type = 0;
+ 	int wed_index = -1;
+ 	u16 addr_type = 0;
+-	u32 timestamp;
+ 	u8 l4proto = 0;
+ 	int err = 0;
+-	int hash;
+ 	int i;
+ 
+ 	if (rhashtable_lookup(&eth->flow_table, &f->cookie, mtk_flow_ht_params))
+@@ -411,23 +396,21 @@ mtk_flow_offload_replace(struct mtk_eth
+ 		return -ENOMEM;
+ 
+ 	entry->cookie = f->cookie;
+-	timestamp = mtk_eth_timestamp(eth);
+-	hash = mtk_foe_entry_commit(eth->ppe, &foe, timestamp);
+-	if (hash < 0) {
+-		err = hash;
++	memcpy(&entry->data, &foe, sizeof(entry->data));
++	entry->wed_index = wed_index;
++
++	if (mtk_foe_entry_commit(eth->ppe, entry) < 0)
+ 		goto free;
+-	}
+ 
+-	entry->hash = hash;
+-	entry->wed_index = wed_index;
+ 	err = rhashtable_insert_fast(&eth->flow_table, &entry->node,
+ 				     mtk_flow_ht_params);
+ 	if (err < 0)
+-		goto clear_flow;
++		goto clear;
+ 
+ 	return 0;
+-clear_flow:
+-	mtk_foe_entry_clear(eth->ppe, hash);
++
++clear:
++	mtk_foe_entry_clear(eth->ppe, entry);
+ free:
+ 	kfree(entry);
+ 	if (wed_index >= 0)
+@@ -445,7 +428,7 @@ mtk_flow_offload_destroy(struct mtk_eth
+ 	if (!entry)
+ 		return -ENOENT;
+ 
+-	mtk_foe_entry_clear(eth->ppe, entry->hash);
++	mtk_foe_entry_clear(eth->ppe, entry);
+ 	rhashtable_remove_fast(&eth->flow_table, &entry->node,
+ 			       mtk_flow_ht_params);
+ 	if (entry->wed_index >= 0)
+@@ -459,7 +442,6 @@ static int
+ mtk_flow_offload_stats(struct mtk_eth *eth, struct flow_cls_offload *f)
+ {
+ 	struct mtk_flow_entry *entry;
+-	int timestamp;
+ 	u32 idle;
+ 
+ 	entry = rhashtable_lookup(&eth->flow_table, &f->cookie,
+@@ -467,11 +449,7 @@ mtk_flow_offload_stats(struct mtk_eth *e
+ 	if (!entry)
+ 		return -ENOENT;
+ 
+-	timestamp = mtk_foe_entry_timestamp(eth->ppe, entry->hash);
+-	if (timestamp < 0)
+-		return -ETIMEDOUT;
+-
+-	idle = mtk_eth_timestamp(eth) - timestamp;
++	idle = mtk_foe_entry_idle_time(eth->ppe, entry);
+ 	f->stats.lastused = jiffies - idle * HZ;
+ 
+ 	return 0;