[Patch net-next v2 3/7] r8169: add support for new interrupt mapping

[javen <javen_xu@realsil.com.cn>]

From: Javen Xu <javen_xu@realsil.com.cn>

To support RSS, the number of hardware interrupt bits should match the
interrupt of software. So we add support for new interrupt mapping here.
ISR_VER_MAP_REG is the hardware register to indicate interrupt status.
IMR_SET_VEC_MAP_REG is interrupt mask which is set to enable irq.

Signed-off-by: Javen Xu <javen_xu@realsil.com.cn>
---
 drivers/net/ethernet/realtek/r8169_main.c | 158 ++++++++++++++++++++--
 1 file changed, 147 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index 29fcd469eebb..bb72a2030f44 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -77,6 +77,7 @@
 #define R8169_TX_STOP_THRS	(MAX_SKB_FRAGS + 1)
 #define R8169_TX_START_THRS	(2 * R8169_TX_STOP_THRS)
 #define R8169_MAX_RX_QUEUES	8
+#define R8127_MAX_TX_QUEUES	8
 #define R8169_MAX_MSIX_VEC	32
 #define R8127_MAX_RX_QUEUES	8
 #define R8169_DEFAULT_RX_QUEUES	1
@@ -452,8 +453,13 @@ enum rtl8125_registers {
 	RSS_CTRL_8125		= 0x4500,
 	Q_NUM_CTRL_8125		= 0x4800,
 	EEE_TXIDLE_TIMER_8125	= 0x6048,
+	IMR_CLEAR_VEC_MAP_REG	= 0x0d00,
+	ISR_VEC_MAP_REG		= 0x0d04,
+	IMR_SET_VEC_MAP_REG	= 0x0d0c,
 };
 
+#define MSIX_ID_VEC_MAP_LINKCHG	29
+#define RTL_VEC_MAP_ENABLE	BIT(0)
 #define LEDSEL_MASK_8125	0x23f
 
 #define RX_VLAN_INNER_8125	BIT(22)
@@ -584,6 +590,9 @@ enum rtl_register_content {
 
 	/* magic enable v2 */
 	MagicPacket_v2	= (1 << 16),	/* Wake up when receives a Magic Packet */
+#define	ISRIMR_LINKCHG	BIT(29)
+#define	ISRIMR_TOK_Q0	BIT(8)
+#define	ISRIMR_ROK_Q0	BIT(0)
 };
 
 enum rtl_desc_bit {
@@ -750,6 +759,7 @@ struct rtl8169_rx_ring {
 struct rtl8169_napi {
 	struct napi_struct napi;
 	void *priv;
+	int index;
 };
 
 struct rtl8169_irq {
@@ -787,6 +797,7 @@ struct rtl8169_private {
 	u8 hw_curr_isr_ver;
 	u8 irq_nvecs;
 	bool recheck_desc_ownbit;
+	unsigned int features;
 	int irq;
 	struct clk *clk;
 
@@ -1685,26 +1696,36 @@ static u32 rtl_get_events(struct rtl8169_private *tp)
 
 static void rtl_ack_events(struct rtl8169_private *tp, u32 bits)
 {
-	if (rtl_is_8125(tp))
+	if (rtl_is_8125(tp)) {
 		RTL_W32(tp, IntrStatus_8125, bits);
-	else
+		if (tp->features & RTL_VEC_MAP_ENABLE)
+			RTL_W32(tp, ISR_VEC_MAP_REG, 0xffffffff);
+	} else {
 		RTL_W16(tp, IntrStatus, bits);
+	}
 }
 
 static void rtl_irq_disable(struct rtl8169_private *tp)
 {
-	if (rtl_is_8125(tp))
+	if (rtl_is_8125(tp)) {
 		RTL_W32(tp, IntrMask_8125, 0);
-	else
+		if (tp->features & RTL_VEC_MAP_ENABLE)
+			RTL_W32(tp, IMR_CLEAR_VEC_MAP_REG, 0xffffffff);
+	} else {
 		RTL_W16(tp, IntrMask, 0);
+	}
 }
 
 static void rtl_irq_enable(struct rtl8169_private *tp)
 {
-	if (rtl_is_8125(tp))
-		RTL_W32(tp, IntrMask_8125, tp->irq_mask);
-	else
+	if (rtl_is_8125(tp)) {
+		if (tp->features & RTL_VEC_MAP_ENABLE)
+			RTL_W32(tp, IMR_SET_VEC_MAP_REG, tp->irq_mask);
+		else
+			RTL_W32(tp, IntrMask_8125, tp->irq_mask);
+	} else {
 		RTL_W16(tp, IntrMask, tp->irq_mask);
+	}
 }
 
 static void rtl8169_irq_mask_and_ack(struct rtl8169_private *tp)
@@ -5080,6 +5101,44 @@ static void rtl8169_free_irq(struct rtl8169_private *tp)
 	}
 }
 
+static void rtl8169_disable_hw_interrupt_msix(struct rtl8169_private *tp, int message_id)
+{
+	RTL_W32(tp, IMR_CLEAR_VEC_MAP_REG, BIT(message_id));
+}
+
+static void rtl8169_clear_hw_isr(struct rtl8169_private *tp, int message_id)
+{
+	RTL_W32(tp, ISR_VEC_MAP_REG, BIT(message_id));
+}
+
+static void rtl8169_enable_hw_interrupt_msix(struct rtl8169_private *tp, int message_id)
+{
+	RTL_W32(tp, IMR_SET_VEC_MAP_REG, BIT(message_id));
+}
+
+static irqreturn_t rtl8169_interrupt_msix(int irq, void *dev_instance)
+{
+	struct rtl8169_napi *napi = dev_instance;
+	struct rtl8169_private *tp = napi->priv;
+	int message_id = napi->index;
+
+	rtl8169_disable_hw_interrupt_msix(tp, message_id);
+
+	rtl8169_clear_hw_isr(tp, message_id);
+
+	if (message_id == MSIX_ID_VEC_MAP_LINKCHG) {
+		phy_mac_interrupt(tp->phydev);
+		rtl8169_enable_hw_interrupt_msix(tp, message_id);
+		return IRQ_HANDLED;
+	}
+
+	tp->recheck_desc_ownbit = true;
+
+	napi_schedule(&napi->napi);
+
+	return IRQ_HANDLED;
+}
+
 static int rtl8169_request_irq(struct rtl8169_private *tp)
 {
 	struct net_device *dev = tp->dev;
@@ -5089,8 +5148,11 @@ static int rtl8169_request_irq(struct rtl8169_private *tp)
 
 	for (int i = 0; i < tp->irq_nvecs; i++) {
 		irq = &tp->irq_tbl[i];
+		if (tp->features & RTL_VEC_MAP_ENABLE && tp->hw_curr_isr_ver > 1)
+			irq->handler = rtl8169_interrupt_msix;
+		else
+			irq->handler = rtl8169_interrupt;
 		napi = &tp->r8169napi[i];
-		irq->handler = rtl8169_interrupt;
 		rc = pci_request_irq(tp->pci_dev, i, irq->handler,
 				     NULL, napi, "%s-%d", dev->name, i);
 		if (rc)
@@ -5539,10 +5601,16 @@ static const struct net_device_ops rtl_netdev_ops = {
 
 static void rtl_set_irq_mask(struct rtl8169_private *tp)
 {
-	tp->irq_mask = RxOK | RxErr | TxOK | TxErr | LinkChg;
+	if (tp->features & RTL_VEC_MAP_ENABLE) {
+		tp->irq_mask = ISRIMR_LINKCHG | ISRIMR_TOK_Q0;
+		for (int i = 0; i < tp->num_rx_rings; i++)
+			tp->irq_mask |= ISRIMR_ROK_Q0 << i;
+	} else {
+		tp->irq_mask = RxOK | RxErr | TxOK | TxErr | LinkChg;
 
-	if (tp->mac_version <= RTL_GIGA_MAC_VER_06)
-		tp->irq_mask |= SYSErr | RxFIFOOver;
+		if (tp->mac_version <= RTL_GIGA_MAC_VER_06)
+			tp->irq_mask |= SYSErr | RxFIFOOver;
+	}
 }
 
 static int rtl_alloc_irq(struct rtl8169_private *tp)
@@ -5573,6 +5641,9 @@ static int rtl_alloc_irq(struct rtl8169_private *tp)
 	tp->irq = pci_irq_vector(pdev, 0);
 	tp->irq_nvecs = nvecs;
 
+	if (nvecs > 1)
+		tp->features |= RTL_VEC_MAP_ENABLE;
+
 	return 0;
 }
 
@@ -5839,6 +5910,53 @@ static bool rtl_aspm_is_safe(struct rtl8169_private *tp)
 	return false;
 }
 
+static int rtl8169_poll_msix_rx(struct napi_struct *napi, int budget)
+{
+	struct rtl8169_napi *r8169_napi = container_of(napi, struct rtl8169_napi, napi);
+	struct rtl8169_private *tp = r8169_napi->priv;
+	const int message_id = r8169_napi->index;
+	struct net_device *dev = tp->dev;
+	int work_done = 0;
+
+	if (message_id < tp->num_rx_rings)
+		work_done += rtl_rx(dev, tp, &tp->rx_ring[message_id], budget);
+
+	if (work_done < budget && napi_complete_done(napi, work_done))
+		rtl8169_enable_hw_interrupt_msix(tp, message_id);
+
+	return work_done;
+}
+
+static int rtl8169_poll_msix_tx(struct napi_struct *napi, int budget)
+{
+	struct rtl8169_napi *r8169_napi = container_of(napi, struct rtl8169_napi, napi);
+	struct rtl8169_private *tp = r8169_napi->priv;
+	const int message_id = r8169_napi->index;
+	int tx_ring_idx = message_id - 8;
+	struct net_device *dev = tp->dev;
+	unsigned int work_done = 0;
+
+	if (tx_ring_idx >= 0)
+		rtl_tx(dev, tp, budget);
+
+	if (work_done < budget && napi_complete_done(napi, work_done))
+		rtl8169_enable_hw_interrupt_msix(tp, message_id);
+
+	return work_done;
+}
+
+static int rtl8169_poll_msix_other(struct napi_struct *napi, int budget)
+{
+	struct rtl8169_napi *r8169_napi = container_of(napi, struct rtl8169_napi, napi);
+	struct rtl8169_private *tp = r8169_napi->priv;
+	const int message_id = r8169_napi->index;
+
+	napi_complete_done(napi, budget);
+	rtl8169_enable_hw_interrupt_msix(tp, message_id);
+
+	return 1;
+}
+
 static void r8169_init_napi(struct rtl8169_private *tp)
 {
 	for (int i = 0; i < tp->irq_nvecs; i++) {
@@ -5846,8 +5964,25 @@ static void r8169_init_napi(struct rtl8169_private *tp)
 		int (*poll)(struct napi_struct *napi, int budget);
 
 		poll = rtl8169_poll;
+		if (tp->features & RTL_VEC_MAP_ENABLE) {
+			switch (tp->hw_curr_isr_ver) {
+			case 6:
+				if (i < R8127_MAX_RX_QUEUES)
+					poll = rtl8169_poll_msix_rx;
+				else if (i >= R8127_MAX_RX_QUEUES &&
+					 i < (R8127_MAX_RX_QUEUES +
+					 R8127_MAX_TX_QUEUES))
+					poll = rtl8169_poll_msix_tx;
+				else
+					poll = rtl8169_poll_msix_other;
+				break;
+			default:
+				break;
+			}
+		}
 		netif_napi_add(tp->dev, &r8169napi->napi, poll);
 		r8169napi->priv = tp;
+		r8169napi->index = i;
 	}
 }
 
@@ -5975,6 +6110,7 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 	if (!tp->rss_support) {
 		netif_napi_add(dev, &tp->r8169napi[0].napi, rtl8169_poll);
 		tp->r8169napi[0].priv = tp;
+		tp->r8169napi[0].index = 0;
 	} else {
 		r8169_init_napi(tp);
 	}
-- 
2.43.0