rockchip_canfd-tx.c

  1// SPDX-License-Identifier: GPL-2.0
  2//
  3// Copyright (c) 2023, 2024 Pengutronix,
  4//               Marc Kleine-Budde <kernel@pengutronix.de>
  5//
  6
  7#include <net/netdev_queues.h>
  8
  9#include "rockchip_canfd.h"
 10
 11static bool rkcanfd_tx_tail_is_eff(const struct rkcanfd_priv *priv)
 12{
 13	const struct canfd_frame *cfd;
 14	const struct sk_buff *skb;
 15	unsigned int tx_tail;
 16
 17	if (!rkcanfd_get_tx_pending(priv))
 18		return false;
 19
 20	tx_tail = rkcanfd_get_tx_tail(priv);
 21	skb = priv->can.echo_skb[tx_tail];
 22	if (!skb) {
 23		netdev_err(priv->ndev,
 24			   "%s: echo_skb[%u]=NULL tx_head=0x%08x tx_tail=0x%08x\n",
 25			   __func__, tx_tail,
 26			   priv->tx_head, priv->tx_tail);
 27
 28		return false;
 29	}
 30
 31	cfd = (struct canfd_frame *)skb->data;
 32
 33	return cfd->can_id & CAN_EFF_FLAG;
 34}
 35
 36unsigned int rkcanfd_get_effective_tx_free(const struct rkcanfd_priv *priv)
 37{
 38	if (priv->devtype_data.quirks & RKCANFD_QUIRK_RK3568_ERRATUM_6 &&
 39	    rkcanfd_tx_tail_is_eff(priv))
 40		return 0;
 41
 42	return rkcanfd_get_tx_free(priv);
 43}
 44
 45static void rkcanfd_start_xmit_write_cmd(const struct rkcanfd_priv *priv,
 46					 const u32 reg_cmd)
 47{
 48	if (priv->devtype_data.quirks & RKCANFD_QUIRK_RK3568_ERRATUM_12)
 49		rkcanfd_write(priv, RKCANFD_REG_MODE, priv->reg_mode_default |
 50			      RKCANFD_REG_MODE_SPACE_RX_MODE);
 51
 52	rkcanfd_write(priv, RKCANFD_REG_CMD, reg_cmd);
 53
 54	if (priv->devtype_data.quirks & RKCANFD_QUIRK_RK3568_ERRATUM_12)
 55		rkcanfd_write(priv, RKCANFD_REG_MODE, priv->reg_mode_default);
 56}
 57
 58void rkcanfd_xmit_retry(struct rkcanfd_priv *priv)
 59{
 60	const unsigned int tx_head = rkcanfd_get_tx_head(priv);
 61	const u32 reg_cmd = RKCANFD_REG_CMD_TX_REQ(tx_head);
 62
 63	rkcanfd_start_xmit_write_cmd(priv, reg_cmd);
 64}
 65
 66netdev_tx_t rkcanfd_start_xmit(struct sk_buff *skb, struct net_device *ndev)
 67{
 68	struct rkcanfd_priv *priv = netdev_priv(ndev);
 69	u32 reg_frameinfo, reg_id, reg_cmd;
 70	unsigned int tx_head, frame_len;
 71	const struct canfd_frame *cfd;
 72	int err;
 73	u8 i;
 74
 75	if (can_dev_dropped_skb(ndev, skb))
 76		return NETDEV_TX_OK;
 77
 78	if (!netif_subqueue_maybe_stop(priv->ndev, 0,
 79				       rkcanfd_get_effective_tx_free(priv),
 80				       RKCANFD_TX_STOP_THRESHOLD,
 81				       RKCANFD_TX_START_THRESHOLD)) {
 82		if (net_ratelimit())
 83			netdev_info(priv->ndev,
 84				    "Stopping tx-queue (tx_head=0x%08x, tx_tail=0x%08x, tx_pending=%d)\n",
 85				    priv->tx_head, priv->tx_tail,
 86				    rkcanfd_get_tx_pending(priv));
 87
 88		return NETDEV_TX_BUSY;
 89	}
 90
 91	cfd = (struct canfd_frame *)skb->data;
 92
 93	if (cfd->can_id & CAN_EFF_FLAG) {
 94		reg_frameinfo = RKCANFD_REG_FD_FRAMEINFO_FRAME_FORMAT;
 95		reg_id = FIELD_PREP(RKCANFD_REG_FD_ID_EFF, cfd->can_id);
 96	} else {
 97		reg_frameinfo = 0;
 98		reg_id = FIELD_PREP(RKCANFD_REG_FD_ID_SFF, cfd->can_id);
 99	}
100
101	if (cfd->can_id & CAN_RTR_FLAG)
102		reg_frameinfo |= RKCANFD_REG_FD_FRAMEINFO_RTR;
103
104	if (can_is_canfd_skb(skb)) {
105		reg_frameinfo |= RKCANFD_REG_FD_FRAMEINFO_FDF;
106
107		if (cfd->flags & CANFD_BRS)
108			reg_frameinfo |= RKCANFD_REG_FD_FRAMEINFO_BRS;
109
110		reg_frameinfo |= FIELD_PREP(RKCANFD_REG_FD_FRAMEINFO_DATA_LENGTH,
111					    can_fd_len2dlc(cfd->len));
112	} else {
113		reg_frameinfo |= FIELD_PREP(RKCANFD_REG_FD_FRAMEINFO_DATA_LENGTH,
114					    cfd->len);
115	}
116
117	tx_head = rkcanfd_get_tx_head(priv);
118	reg_cmd = RKCANFD_REG_CMD_TX_REQ(tx_head);
119
120	rkcanfd_write(priv, RKCANFD_REG_FD_TXFRAMEINFO, reg_frameinfo);
121	rkcanfd_write(priv, RKCANFD_REG_FD_TXID, reg_id);
122	for (i = 0; i < cfd->len; i += 4)
123		rkcanfd_write(priv, RKCANFD_REG_FD_TXDATA0 + i,
124			      *(u32 *)(cfd->data + i));
125
126	frame_len = can_skb_get_frame_len(skb);
127	err = can_put_echo_skb(skb, ndev, tx_head, frame_len);
128	if (!err)
129		netdev_sent_queue(priv->ndev, frame_len);
130
131	WRITE_ONCE(priv->tx_head, priv->tx_head + 1);
132
133	rkcanfd_start_xmit_write_cmd(priv, reg_cmd);
134
135	netif_subqueue_maybe_stop(priv->ndev, 0,
136				  rkcanfd_get_effective_tx_free(priv),
137				  RKCANFD_TX_STOP_THRESHOLD,
138				  RKCANFD_TX_START_THRESHOLD);
139
140	return NETDEV_TX_OK;
141}
142
143void rkcanfd_handle_tx_done_one(struct rkcanfd_priv *priv, const u32 ts,
144				unsigned int *frame_len_p)
145{
146	struct net_device_stats *stats = &priv->ndev->stats;
147	unsigned int tx_tail;
148	struct sk_buff *skb;
149
150	tx_tail = rkcanfd_get_tx_tail(priv);
151	skb = priv->can.echo_skb[tx_tail];
152
153	/* Manual handling of CAN Bus Error counters. See
154	 * rkcanfd_get_corrected_berr_counter() for detailed
155	 * explanation.
156	 */
157	if (priv->bec.txerr)
158		priv->bec.txerr--;
159
160	if (skb)
161		rkcanfd_skb_set_timestamp(priv, skb, ts);
162	stats->tx_bytes +=
163		can_rx_offload_get_echo_skb_queue_timestamp(&priv->offload,
164							    tx_tail, ts,
165							    frame_len_p);
166	stats->tx_packets++;
167}