1 files changed, 486 insertions, 0 deletions

diff --git a/drivers/net/ethernet/microchip/sparx5/sparx5_fdma.c b/drivers/net/ethernet/microchip/sparx5/sparx5_fdma.c
new file mode 100644
index 000000000000..dbe86f937b21
--- /dev/null
+++ b/drivers/net/ethernet/microchip/sparx5/sparx5_fdma.c
@@ -0,0 +1,486 @@
+// SPDX-License-Identifier: GPL-2.0+
+/* Microchip Sparx5 Switch driver
+ *
+ * Copyright (c) 2021 Microchip Technology Inc. and its subsidiaries.
+ *
+ * The Sparx5 Chip Register Model can be browsed at this location:
+ * https://github.com/microchip-ung/sparx-5_reginfo
+ */
+
+#include <linux/types.h>
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include <linux/interrupt.h>
+#include <linux/ip.h>
+#include <linux/dma-mapping.h>
+
+#include "sparx5_main_regs.h"
+#include "sparx5_main.h"
+#include "sparx5_port.h"
+
+#define FDMA_XTR_BUFFER_SIZE		2048
+#define FDMA_WEIGHT			4
+
+static int sparx5_fdma_tx_dataptr_cb(struct fdma *fdma, int dcb, int db,
+				     u64 *dataptr)
+{
+	*dataptr = fdma->dma + (sizeof(struct fdma_dcb) * fdma->n_dcbs) +
+		   ((dcb * fdma->n_dbs + db) * fdma->db_size);
+
+	return 0;
+}
+
+static int sparx5_fdma_rx_dataptr_cb(struct fdma *fdma, int dcb, int db,
+				     u64 *dataptr)
+{
+	struct sparx5 *sparx5 = fdma->priv;
+	struct sparx5_rx *rx = &sparx5->rx;
+	struct sk_buff *skb;
+
+	skb = __netdev_alloc_skb(rx->ndev, fdma->db_size, GFP_ATOMIC);
+	if (unlikely(!skb))
+		return -ENOMEM;
+
+	*dataptr = virt_to_phys(skb->data);
+
+	rx->skb[dcb][db] = skb;
+
+	return 0;
+}
+
+static void sparx5_fdma_rx_activate(struct sparx5 *sparx5, struct sparx5_rx *rx)
+{
+	struct fdma *fdma = &rx->fdma;
+
+	/* Write the buffer address in the LLP and LLP1 regs */
+	spx5_wr(((u64)fdma->dma) & GENMASK(31, 0), sparx5,
+		FDMA_DCB_LLP(fdma->channel_id));
+	spx5_wr(((u64)fdma->dma) >> 32, sparx5,
+		FDMA_DCB_LLP1(fdma->channel_id));
+
+	/* Set the number of RX DBs to be used, and DB end-of-frame interrupt */
+	spx5_wr(FDMA_CH_CFG_CH_DCB_DB_CNT_SET(fdma->n_dbs) |
+		FDMA_CH_CFG_CH_INTR_DB_EOF_ONLY_SET(1) |
+		FDMA_CH_CFG_CH_INJ_PORT_SET(XTR_QUEUE),
+		sparx5, FDMA_CH_CFG(fdma->channel_id));
+
+	/* Set the RX Watermark to max */
+	spx5_rmw(FDMA_XTR_CFG_XTR_FIFO_WM_SET(31), FDMA_XTR_CFG_XTR_FIFO_WM,
+		 sparx5,
+		 FDMA_XTR_CFG);
+
+	/* Start RX fdma */
+	spx5_rmw(FDMA_PORT_CTRL_XTR_STOP_SET(0), FDMA_PORT_CTRL_XTR_STOP,
+		 sparx5, FDMA_PORT_CTRL(0));
+
+	/* Enable RX channel DB interrupt */
+	spx5_rmw(BIT(fdma->channel_id),
+		 BIT(fdma->channel_id) & FDMA_INTR_DB_ENA_INTR_DB_ENA,
+		 sparx5, FDMA_INTR_DB_ENA);
+
+	/* Activate the RX channel */
+	spx5_wr(BIT(fdma->channel_id), sparx5, FDMA_CH_ACTIVATE);
+}
+
+static void sparx5_fdma_rx_deactivate(struct sparx5 *sparx5, struct sparx5_rx *rx)
+{
+	struct fdma *fdma = &rx->fdma;
+
+	/* Deactivate the RX channel */
+	spx5_rmw(0, BIT(fdma->channel_id) & FDMA_CH_ACTIVATE_CH_ACTIVATE,
+		 sparx5, FDMA_CH_ACTIVATE);
+
+	/* Disable RX channel DB interrupt */
+	spx5_rmw(0, BIT(fdma->channel_id) & FDMA_INTR_DB_ENA_INTR_DB_ENA,
+		 sparx5, FDMA_INTR_DB_ENA);
+
+	/* Stop RX fdma */
+	spx5_rmw(FDMA_PORT_CTRL_XTR_STOP_SET(1), FDMA_PORT_CTRL_XTR_STOP,
+		 sparx5, FDMA_PORT_CTRL(0));
+}
+
+static void sparx5_fdma_tx_activate(struct sparx5 *sparx5, struct sparx5_tx *tx)
+{
+	struct fdma *fdma = &tx->fdma;
+
+	/* Write the buffer address in the LLP and LLP1 regs */
+	spx5_wr(((u64)fdma->dma) & GENMASK(31, 0), sparx5,
+		FDMA_DCB_LLP(fdma->channel_id));
+	spx5_wr(((u64)fdma->dma) >> 32, sparx5,
+		FDMA_DCB_LLP1(fdma->channel_id));
+
+	/* Set the number of TX DBs to be used, and DB end-of-frame interrupt */
+	spx5_wr(FDMA_CH_CFG_CH_DCB_DB_CNT_SET(fdma->n_dbs) |
+		FDMA_CH_CFG_CH_INTR_DB_EOF_ONLY_SET(1) |
+		FDMA_CH_CFG_CH_INJ_PORT_SET(INJ_QUEUE),
+		sparx5, FDMA_CH_CFG(fdma->channel_id));
+
+	/* Start TX fdma */
+	spx5_rmw(FDMA_PORT_CTRL_INJ_STOP_SET(0), FDMA_PORT_CTRL_INJ_STOP,
+		 sparx5, FDMA_PORT_CTRL(0));
+
+	/* Activate the channel */
+	spx5_wr(BIT(fdma->channel_id), sparx5, FDMA_CH_ACTIVATE);
+}
+
+static void sparx5_fdma_tx_deactivate(struct sparx5 *sparx5, struct sparx5_tx *tx)
+{
+	/* Disable the channel */
+	spx5_rmw(0, BIT(tx->fdma.channel_id) & FDMA_CH_ACTIVATE_CH_ACTIVATE,
+		 sparx5, FDMA_CH_ACTIVATE);
+}
+
+void sparx5_fdma_reload(struct sparx5 *sparx5, struct fdma *fdma)
+{
+	/* Reload the RX channel */
+	spx5_wr(BIT(fdma->channel_id), sparx5, FDMA_CH_RELOAD);
+}
+
+static bool sparx5_fdma_rx_get_frame(struct sparx5 *sparx5, struct sparx5_rx *rx)
+{
+	struct fdma *fdma = &rx->fdma;
+	struct sparx5_port *port;
+	struct fdma_db *db_hw;
+	struct frame_info fi;
+	struct sk_buff *skb;
+
+	/* Check if the DCB is done */
+	db_hw = fdma_db_next_get(fdma);
+	if (unlikely(!fdma_db_is_done(db_hw)))
+		return false;
+	skb = rx->skb[fdma->dcb_index][fdma->db_index];
+	skb_put(skb, fdma_db_len_get(db_hw));
+	/* Now do the normal processing of the skb */
+	sparx5_ifh_parse(sparx5, (u32 *)skb->data, &fi);
+	/* Map to port netdev */
+	port = fi.src_port < sparx5->data->consts->n_ports ?
+		       sparx5->ports[fi.src_port] :
+		       NULL;
+	if (!port || !port->ndev) {
+		dev_err(sparx5->dev, "Data on inactive port %d\n", fi.src_port);
+		sparx5_xtr_flush(sparx5, XTR_QUEUE);
+		return false;
+	}
+	skb->dev = port->ndev;
+	skb_pull(skb, IFH_LEN * sizeof(u32));
+	if (likely(!(skb->dev->features & NETIF_F_RXFCS)))
+		skb_trim(skb, skb->len - ETH_FCS_LEN);
+
+	sparx5_ptp_rxtstamp(sparx5, skb, fi.timestamp);
+	skb->protocol = eth_type_trans(skb, skb->dev);
+	/* Everything we see on an interface that is in the HW bridge
+	 * has already been forwarded
+	 */
+	if (test_bit(port->portno, sparx5->bridge_mask))
+		skb->offload_fwd_mark = 1;
+	skb->dev->stats.rx_bytes += skb->len;
+	skb->dev->stats.rx_packets++;
+	rx->packets++;
+	netif_receive_skb(skb);
+	return true;
+}
+
+int sparx5_fdma_napi_callback(struct napi_struct *napi, int weight)
+{
+	struct sparx5_rx *rx = container_of(napi, struct sparx5_rx, napi);
+	struct sparx5 *sparx5 = container_of(rx, struct sparx5, rx);
+	struct fdma *fdma = &rx->fdma;
+	int counter = 0;
+
+	while (counter < weight && sparx5_fdma_rx_get_frame(sparx5, rx)) {
+		fdma_db_advance(fdma);
+		counter++;
+		/* Check if the DCB can be reused */
+		if (fdma_dcb_is_reusable(fdma))
+			continue;
+		fdma_dcb_add(fdma, fdma->dcb_index,
+			     FDMA_DCB_INFO_DATAL(fdma->db_size),
+			     FDMA_DCB_STATUS_INTR);
+		fdma_db_reset(fdma);
+		fdma_dcb_advance(fdma);
+	}
+	if (counter < weight) {
+		napi_complete_done(&rx->napi, counter);
+		spx5_rmw(BIT(fdma->channel_id),
+			 BIT(fdma->channel_id) & FDMA_INTR_DB_ENA_INTR_DB_ENA,
+			 sparx5, FDMA_INTR_DB_ENA);
+	}
+	if (counter)
+		sparx5_fdma_reload(sparx5, fdma);
+	return counter;
+}
+
+int sparx5_fdma_xmit(struct sparx5 *sparx5, u32 *ifh, struct sk_buff *skb,
+		     struct net_device *dev)
+{
+	struct sparx5_tx *tx = &sparx5->tx;
+	struct fdma *fdma = &tx->fdma;
+	void *virt_addr;
+
+	fdma_dcb_advance(fdma);
+	if (!fdma_db_is_done(fdma_db_get(fdma, fdma->dcb_index, 0)))
+		return -EINVAL;
+
+	/* Get the virtual address of the dataptr for the next DB */
+	virt_addr = ((u8 *)fdma->dcbs +
+		     (sizeof(struct fdma_dcb) * fdma->n_dcbs) +
+		     ((fdma->dcb_index * fdma->n_dbs) * fdma->db_size));
+
+	memcpy(virt_addr, ifh, IFH_LEN * 4);
+	memcpy(virt_addr + IFH_LEN * 4, skb->data, skb->len);
+
+	fdma_dcb_add(fdma, fdma->dcb_index, 0,
+		     FDMA_DCB_STATUS_SOF |
+		     FDMA_DCB_STATUS_EOF |
+		     FDMA_DCB_STATUS_BLOCKO(0) |
+		     FDMA_DCB_STATUS_BLOCKL(skb->len + IFH_LEN * 4 + 4));
+
+	sparx5_fdma_reload(sparx5, fdma);
+
+	return NETDEV_TX_OK;
+}
+
+static int sparx5_fdma_rx_alloc(struct sparx5 *sparx5)
+{
+	struct sparx5_rx *rx = &sparx5->rx;
+	struct fdma *fdma = &rx->fdma;
+	int err;
+
+	err = fdma_alloc_phys(fdma);
+	if (err)
+		return err;
+
+	fdma_dcbs_init(fdma, FDMA_DCB_INFO_DATAL(fdma->db_size),
+		       FDMA_DCB_STATUS_INTR);
+
+	return 0;
+}
+
+static int sparx5_fdma_tx_alloc(struct sparx5 *sparx5)
+{
+	struct sparx5_tx *tx = &sparx5->tx;
+	struct fdma *fdma = &tx->fdma;
+	int err;
+
+	err = fdma_alloc_phys(fdma);
+	if (err)
+		return err;
+
+	fdma_dcbs_init(fdma, FDMA_DCB_INFO_DATAL(fdma->db_size),
+		       FDMA_DCB_STATUS_DONE);
+
+	return 0;
+}
+
+static void sparx5_fdma_rx_init(struct sparx5 *sparx5,
+				struct sparx5_rx *rx, int channel)
+{
+	struct fdma *fdma = &rx->fdma;
+	int idx;
+
+	fdma->channel_id = channel;
+	fdma->n_dcbs = FDMA_DCB_MAX;
+	fdma->n_dbs = FDMA_RX_DCB_MAX_DBS;
+	fdma->priv = sparx5;
+	fdma->db_size = ALIGN(FDMA_XTR_BUFFER_SIZE, PAGE_SIZE);
+	fdma->size = fdma_get_size(&sparx5->rx.fdma);
+	fdma->ops.dataptr_cb = &sparx5_fdma_rx_dataptr_cb;
+	fdma->ops.nextptr_cb = &fdma_nextptr_cb;
+	/* Fetch a netdev for SKB and NAPI use, any will do */
+	for (idx = 0; idx < sparx5->data->consts->n_ports; ++idx) {
+		struct sparx5_port *port = sparx5->ports[idx];
+
+		if (port && port->ndev) {
+			rx->ndev = port->ndev;
+			break;
+		}
+	}
+}
+
+static void sparx5_fdma_tx_init(struct sparx5 *sparx5,
+				struct sparx5_tx *tx, int channel)
+{
+	struct fdma *fdma = &tx->fdma;
+
+	fdma->channel_id = channel;
+	fdma->n_dcbs = FDMA_DCB_MAX;
+	fdma->n_dbs = FDMA_TX_DCB_MAX_DBS;
+	fdma->priv = sparx5;
+	fdma->db_size = ALIGN(FDMA_XTR_BUFFER_SIZE, PAGE_SIZE);
+	fdma->size = fdma_get_size_contiguous(&sparx5->tx.fdma);
+	fdma->ops.dataptr_cb = &sparx5_fdma_tx_dataptr_cb;
+	fdma->ops.nextptr_cb = &fdma_nextptr_cb;
+}
+
+irqreturn_t sparx5_fdma_handler(int irq, void *args)
+{
+	struct sparx5 *sparx5 = args;
+	u32 db = 0, err = 0;
+
+	db = spx5_rd(sparx5, FDMA_INTR_DB);
+	err = spx5_rd(sparx5, FDMA_INTR_ERR);
+	/* Clear interrupt */
+	if (db) {
+		spx5_wr(0, sparx5, FDMA_INTR_DB_ENA);
+		spx5_wr(db, sparx5, FDMA_INTR_DB);
+		napi_schedule(&sparx5->rx.napi);
+	}
+	if (err) {
+		u32 err_type = spx5_rd(sparx5, FDMA_ERRORS);
+
+		dev_err_ratelimited(sparx5->dev,
+				    "ERR: int: %#x, type: %#x\n",
+				    err, err_type);
+		spx5_wr(err, sparx5, FDMA_INTR_ERR);
+		spx5_wr(err_type, sparx5, FDMA_ERRORS);
+	}
+	return IRQ_HANDLED;
+}
+
+void sparx5_fdma_injection_mode(struct sparx5 *sparx5)
+{
+	const int byte_swap = 1;
+	int portno;
+	int urgency;
+
+	/* Change mode to fdma extraction and injection */
+	spx5_wr(QS_XTR_GRP_CFG_MODE_SET(2) |
+		QS_XTR_GRP_CFG_STATUS_WORD_POS_SET(1) |
+		QS_XTR_GRP_CFG_BYTE_SWAP_SET(byte_swap),
+		sparx5, QS_XTR_GRP_CFG(XTR_QUEUE));
+	spx5_wr(QS_INJ_GRP_CFG_MODE_SET(2) |
+		QS_INJ_GRP_CFG_BYTE_SWAP_SET(byte_swap),
+		sparx5, QS_INJ_GRP_CFG(INJ_QUEUE));
+
+	/* CPU ports capture setup */
+	for (portno = sparx5_get_internal_port(sparx5, SPX5_PORT_CPU_0);
+	     portno <= sparx5_get_internal_port(sparx5, SPX5_PORT_CPU_1);
+	     portno++) {
+		/* ASM CPU port: No preamble, IFH, enable padding */
+		spx5_wr(ASM_PORT_CFG_PAD_ENA_SET(1) |
+			ASM_PORT_CFG_NO_PREAMBLE_ENA_SET(1) |
+			ASM_PORT_CFG_INJ_FORMAT_CFG_SET(1), /* 1 = IFH */
+			sparx5, ASM_PORT_CFG(portno));
+
+		/* Reset WM cnt to unclog queued frames */
+		spx5_rmw(DSM_DEV_TX_STOP_WM_CFG_DEV_TX_CNT_CLR_SET(1),
+			 DSM_DEV_TX_STOP_WM_CFG_DEV_TX_CNT_CLR,
+			 sparx5,
+			 DSM_DEV_TX_STOP_WM_CFG(portno));
+
+		/* Set Disassembler Stop Watermark level */
+		spx5_rmw(DSM_DEV_TX_STOP_WM_CFG_DEV_TX_STOP_WM_SET(100),
+			 DSM_DEV_TX_STOP_WM_CFG_DEV_TX_STOP_WM,
+			 sparx5,
+			 DSM_DEV_TX_STOP_WM_CFG(portno));
+
+		/* Enable port in queue system */
+		urgency = sparx5_port_fwd_urg(sparx5, SPEED_2500);
+		spx5_rmw(QFWD_SWITCH_PORT_MODE_PORT_ENA_SET(1) |
+			 QFWD_SWITCH_PORT_MODE_FWD_URGENCY_SET(urgency),
+			 QFWD_SWITCH_PORT_MODE_PORT_ENA |
+			 QFWD_SWITCH_PORT_MODE_FWD_URGENCY,
+			 sparx5,
+			 QFWD_SWITCH_PORT_MODE(portno));
+
+		/* Disable Disassembler buffer underrun watchdog
+		 * to avoid truncated packets in XTR
+		 */
+		spx5_rmw(DSM_BUF_CFG_UNDERFLOW_WATCHDOG_DIS_SET(1),
+			 DSM_BUF_CFG_UNDERFLOW_WATCHDOG_DIS,
+			 sparx5,
+			 DSM_BUF_CFG(portno));
+
+		/* Disabling frame aging */
+		spx5_rmw(HSCH_PORT_MODE_AGE_DIS_SET(1),
+			 HSCH_PORT_MODE_AGE_DIS,
+			 sparx5,
+			 HSCH_PORT_MODE(portno));
+	}
+}
+
+int sparx5_fdma_init(struct sparx5 *sparx5)
+{
+	int err;
+
+	/* Reset FDMA state */
+	spx5_wr(FDMA_CTRL_NRESET_SET(0), sparx5, FDMA_CTRL);
+	spx5_wr(FDMA_CTRL_NRESET_SET(1), sparx5, FDMA_CTRL);
+
+	/* Force ACP caching but disable read/write allocation */
+	spx5_rmw(CPU_PROC_CTRL_ACP_CACHE_FORCE_ENA_SET(1) |
+		 CPU_PROC_CTRL_ACP_AWCACHE_SET(0) |
+		 CPU_PROC_CTRL_ACP_ARCACHE_SET(0),
+		 CPU_PROC_CTRL_ACP_CACHE_FORCE_ENA |
+		 CPU_PROC_CTRL_ACP_AWCACHE |
+		 CPU_PROC_CTRL_ACP_ARCACHE,
+		 sparx5, CPU_PROC_CTRL);
+
+	sparx5_fdma_injection_mode(sparx5);
+	sparx5_fdma_rx_init(sparx5, &sparx5->rx, FDMA_XTR_CHANNEL);
+	sparx5_fdma_tx_init(sparx5, &sparx5->tx, FDMA_INJ_CHANNEL);
+	err = sparx5_fdma_rx_alloc(sparx5);
+	if (err) {
+		dev_err(sparx5->dev, "Could not allocate RX buffers: %d\n", err);
+		return err;
+	}
+	err = sparx5_fdma_tx_alloc(sparx5);
+	if (err) {
+		dev_err(sparx5->dev, "Could not allocate TX buffers: %d\n", err);
+		return err;
+	}
+	return err;
+}
+
+int sparx5_fdma_deinit(struct sparx5 *sparx5)
+{
+	sparx5_fdma_stop(sparx5);
+	fdma_free_phys(&sparx5->rx.fdma);
+	fdma_free_phys(&sparx5->tx.fdma);
+
+	return 0;
+}
+
+static u32 sparx5_fdma_port_ctrl(struct sparx5 *sparx5)
+{
+	return spx5_rd(sparx5, FDMA_PORT_CTRL(0));
+}
+
+int sparx5_fdma_start(struct sparx5 *sparx5)
+{
+	const struct sparx5_ops *ops = sparx5->data->ops;
+	struct sparx5_rx *rx = &sparx5->rx;
+	struct sparx5_tx *tx = &sparx5->tx;
+
+	netif_napi_add_weight(rx->ndev,
+			      &rx->napi,
+			      ops->fdma_poll,
+			      FDMA_WEIGHT);
+
+	napi_enable(&rx->napi);
+
+	sparx5_fdma_rx_activate(sparx5, rx);
+	sparx5_fdma_tx_activate(sparx5, tx);
+
+	return 0;
+}
+
+int sparx5_fdma_stop(struct sparx5 *sparx5)
+{
+	struct sparx5_rx *rx = &sparx5->rx;
+	struct sparx5_tx *tx = &sparx5->tx;
+	u32 val;
+
+	napi_disable(&rx->napi);
+
+	/* Stop the fdma and channel interrupts */
+	sparx5_fdma_rx_deactivate(sparx5, rx);
+	sparx5_fdma_tx_deactivate(sparx5, tx);
+
+	/* Wait for the RX channel to stop */
+	read_poll_timeout(sparx5_fdma_port_ctrl, val,
+			  FDMA_PORT_CTRL_XTR_BUF_IS_EMPTY_GET(val) == 0,
+			  500, 10000, 0, sparx5);
+
+	return 0;
+}