[PATCH v1 3/4] can: cast: add driver for CAST CAN controller
William Qiu
william.qiu at starfivetech.com
Sun Jan 28 19:12:38 PST 2024
Add driver for CAST CAN Controller. And add compatibility code which
based on StarFive JH7110 SoC.
Signed-off-by: William Qiu <william.qiu at starfivetech.com>
---
MAINTAINERS | 7 +
drivers/net/can/Kconfig | 7 +
drivers/net/can/Makefile | 1 +
drivers/net/can/cast_can.c | 1215 ++++++++++++++++++++++++++++++++++++
4 files changed, 1230 insertions(+)
create mode 100644 drivers/net/can/cast_can.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 8d1052fa6a69..daa3af8b4f10 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4723,6 +4723,13 @@ S: Maintained
W: https://wireless.wiki.kernel.org/en/users/Drivers/carl9170
F: drivers/net/wireless/ath/carl9170/
+CAST CAN DRIVER
+M: William Qiu <william.qiu at starfivetech.com>
+L: linux-can at vger.kernel.org
+S: Supported
+F: Documentation/devicetree/bindings/net/can/cast,can.yaml
+F: drivers/net/can/cast_can.c
+
CAVIUM I2C DRIVER
M: Robert Richter <rric at kernel.org>
S: Odd Fixes
diff --git a/drivers/net/can/Kconfig b/drivers/net/can/Kconfig
index eb410714afc2..d98ad06c8ff3 100644
--- a/drivers/net/can/Kconfig
+++ b/drivers/net/can/Kconfig
@@ -124,6 +124,13 @@ config CAN_CAN327
If this driver is built as a module, it will be called can327.
+config CAN_CASTCAN
+ tristate "CAST CAN"
+ depends on ARCH_STARFIVE || COMPILE_TEST
+ depends on COMMON_CLK && HAS_IOMEM
+ help
+ CAST CAN driver. This driver supports both CAN and CANFD IP.
+
config CAN_FLEXCAN
tristate "Support for Freescale FLEXCAN based chips"
depends on OF || COLDFIRE || COMPILE_TEST
diff --git a/drivers/net/can/Makefile b/drivers/net/can/Makefile
index ff8f76295d13..d6fa47278859 100644
--- a/drivers/net/can/Makefile
+++ b/drivers/net/can/Makefile
@@ -16,6 +16,7 @@ obj-y += softing/
obj-$(CONFIG_CAN_AT91) += at91_can.o
obj-$(CONFIG_CAN_BXCAN) += bxcan.o
obj-$(CONFIG_CAN_CAN327) += can327.o
+obj-$(CONFIG_CAN_CASTCAN) += cast_can.o
obj-$(CONFIG_CAN_CC770) += cc770/
obj-$(CONFIG_CAN_C_CAN) += c_can/
obj-$(CONFIG_CAN_CTUCANFD) += ctucanfd/
diff --git a/drivers/net/can/cast_can.c b/drivers/net/can/cast_can.c
new file mode 100644
index 000000000000..404e050e41a0
--- /dev/null
+++ b/drivers/net/can/cast_can.c
@@ -0,0 +1,1215 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * CAST Controller Area Network Host Controller Driver
+ *
+ * Copyright (c) 2022-2023 StarFive Technology Co., Ltd.
+ */
+
+#include <linux/can/dev.h>
+#include <linux/can/error.h>
+#include <linux/clk.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/of_device.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <linux/skbuff.h>
+#include <linux/string.h>
+#include <linux/types.h>
+
+#define DRIVER_NAME "cast_can"
+
+/* CAN registers set */
+enum ccan_device_reg {
+ CCAN_RUBF_OFFSET = 0x00, /* Receive Buffer Registers 0x00-0x4f */
+ CCAN_RUBF_ID_OFFSET = 0x00,
+ CCAN_RBUF_CTL_OFFSET = 0x04,
+ CCAN_RBUF_DATA_OFFSET = 0x08,
+ CCAN_TBUF_OFFSET = 0x50, /* Transmit Buffer Registers 0x50-0x97 */
+ CCAN_TBUF_ID_OFFSET = 0x50,
+ CCAN_TBUF_CTL_OFFSET = 0x54,
+ CCAN_TBUF_DATA_OFFSET = 0x58,
+ CCAN_TTS_OFFSET = 0x98, /* Transmission Time Stamp 0x98-0x9f */
+ CCAN_CFG_STAT_OFFSET = 0xa0,
+ CCAN_TCMD_OFFSET = 0xa1,
+ CCAN_TCTRL_OFFSET = 0xa2,
+ CCAN_RCTRL_OFFSET = 0xa3,
+ CCAN_RTIE_OFFSET = 0xa4,
+ CCAN_RTIF_OFFSET = 0xa5,
+ CCAN_ERRINT_OFFSET = 0xa6,
+ CCAN_LIMIT_OFFSET = 0xa7,
+ CCAN_S_SEG_1_OFFSET = 0xa8,
+ CCAN_S_SEG_2_OFFSET = 0xa9,
+ CCAN_S_SJW_OFFSET = 0xaa,
+ CCAN_S_PRESC_OFFSET = 0xab,
+ CCAN_F_SEG_1_OFFSET = 0xac,
+ CCAN_F_SEG_2_OFFSET = 0xad,
+ CCAN_F_SJW_OFFSET = 0xae,
+ CCAN_F_PRESC_OFFSET = 0xaf,
+ CCAN_EALCAP_OFFSET = 0xb0,
+ CCAN_RECNT_OFFSET = 0xb2,
+ CCAN_TECNT_OFFSET = 0xb3,
+};
+
+enum ccan_reg_bitchange {
+ CCAN_SET_RST_MASK = 0x80, /* Set Reset Bit */
+ CCAN_OFF_RST_MASK = 0x7f, /* Reset Off Bit */
+ CCAN_SET_FULLCAN_MASK = 0x10, /* set TTTBM as 1->full TTCAN mode */
+ CCAN_OFF_FULLCAN_MASK = 0xef, /* set TTTBM as 0->separate PTB and STB mode */
+ CCAN_SET_FIFO_MASK = 0x20, /* set TSMODE as 1->FIFO mode */
+ CCAN_OFF_FIFO_MASK = 0xdf, /* set TSMODE as 0->Priority mode */
+ CCAN_SET_TSONE_MASK = 0x04,
+ CCAN_OFF_TSONE_MASK = 0xfb,
+ CCAN_SET_TSALL_MASK = 0x02,
+ CCAN_OFF_TSALL_MASK = 0xfd,
+ CCAN_LBMEMOD_MASK = 0x40, /* set loop back mode, external */
+ CCAN_LBMIMOD_MASK = 0x20, /* set loopback internal mode */
+ CCAN_SET_BUSOFF_MASK = 0x01,
+ CCAN_OFF_BUSOFF_MASK = 0xfe,
+ CCAN_SET_TTSEN_MASK = 0x80, /* set ttsen, tts update enable */
+ CCAN_SET_BRS_MASK = 0x10, /* can fd Bit Rate Switch mask */
+ CCAN_OFF_BRS_MASK = 0xef,
+ CCAN_SET_EDL_MASK = 0x20, /* Extended Data Length */
+ CCAN_OFF_EDL_MASK = 0xdf,
+ CCAN_SET_DLC_MASK = 0x0f,
+ CCAN_SET_TENEXT_MASK = 0x40,
+ CCAN_SET_IDE_MASK = 0x80,
+ CCAN_OFF_IDE_MASK = 0x7f,
+ CCAN_SET_RTR_MASK = 0x40,
+ CCAN_OFF_RTR_MASK = 0xbf,
+ CCAN_INTR_ALL_MASK = 0xff, /* all interrupts enable mask */
+ CCAN_SET_RIE_MASK = 0x80,
+ CCAN_OFF_RIE_MASK = 0x7f,
+ CCAN_SET_RFIE_MASK = 0x20,
+ CCAN_OFF_RFIE_MASK = 0xdf,
+ CCAN_SET_RAFIE_MASK = 0x10,
+ CCAN_OFF_RAFIE_MASK = 0xef,
+ CCAN_SET_EIE_MASK = 0x02,
+ CCAN_OFF_EIE_MASK = 0xfd,
+ CCAN_TASCTIVE_MASK = 0x02,
+ CCAN_RASCTIVE_MASK = 0x04,
+ CCAN_SET_TBSEL_MASK = 0x80, /* message writen in STB */
+ CCAN_OFF_TBSEL_MASK = 0x7f, /* message writen in PTB */
+ CCAN_SET_STBY_MASK = 0x20,
+ CCAN_OFF_STBY_MASK = 0xdf,
+ CCAN_SET_TPE_MASK = 0x10, /* Transmit primary enable */
+ CCAN_SET_TPA_MASK = 0x08,
+ CCAN_SET_SACK_MASK = 0x80,
+ CCAN_SET_RREL_MASK = 0x10,
+ CCAN_RSTAT_NOT_EMPTY_MASK = 0x03,
+ CCAN_SET_RIF_MASK = 0x80,
+ CCAN_OFF_RIF_MASK = 0x7f,
+ CCAN_SET_RAFIF_MASK = 0x10,
+ CCAN_SET_RFIF_MASK = 0x20,
+ CCAN_SET_TPIF_MASK = 0x08, /* Transmission Primary Interrupt Flag */
+ CCAN_SET_TSIF_MASK = 0x04,
+ CCAN_SET_EIF_MASK = 0x02,
+ CCAN_SET_AIF_MASK = 0x01,
+ CCAN_SET_EWARN_MASK = 0x80,
+ CCAN_SET_EPASS_MASK = 0x40,
+ CCAN_SET_EPIE_MASK = 0x20,
+ CCAN_SET_EPIF_MASK = 0x10,
+ CCAN_SET_ALIE_MASK = 0x08,
+ CCAN_SET_ALIF_MASK = 0x04,
+ CCAN_SET_BEIE_MASK = 0x02,
+ CCAN_SET_BEIF_MASK = 0x01,
+ CCAN_OFF_EPIE_MASK = 0xdf,
+ CCAN_OFF_BEIE_MASK = 0xfd,
+ CCAN_SET_AFWL_MASK = 0x40,
+ CCAN_SET_EWL_MASK = 0x0b,
+ CCAN_SET_KOER_MASK = 0xe0,
+ CCAN_SET_BIT_ERROR_MASK = 0x20,
+ CCAN_SET_FORM_ERROR_MASK = 0x40,
+ CCAN_SET_STUFF_ERROR_MASK = 0x60,
+ CCAN_SET_ACK_ERROR_MASK = 0x80,
+ CCAN_SET_CRC_ERROR_MASK = 0xa0,
+ CCAN_SET_OTH_ERROR_MASK = 0xc0,
+};
+
+/* seg1,seg2,sjw,prescaler all have 8 bits */
+#define BITS_OF_BITTIMING_REG 8
+
+/* in can_bittiming strucure every field has 32 bits---->u32 */
+#define FBITS_IN_BITTIMING_STR 32
+#define SEG_1_SHIFT 0
+#define SEG_2_SHIFT 8
+#define SJW_SHIFT 16
+#define PRESC_SHIFT 24
+
+/* TTSEN bit used for 32 bit register read or write */
+#define TTSEN_8_32_SHIFT 24
+#define RTR_32_8_SHIFT 24
+
+/* transmit mode */
+#define XMIT_FULL 0
+#define XMIT_SEP_FIFO 1
+#define XMIT_SEP_PRIO 2
+#define XMIT_PTB_MODE 3
+
+enum cast_can_type {
+ CAST_CAN_TYPE_CAN = 0,
+ CAST_CAN_TYPE_CANFD,
+};
+
+struct ccan_priv {
+ struct can_priv can;
+ struct napi_struct napi;
+ struct device *dev;
+ struct regmap *reg_syscon;
+ void __iomem *reg_base;
+ u32 (*read_reg)(const struct ccan_priv *priv, enum ccan_device_reg reg);
+ void (*write_reg)(const struct ccan_priv *priv, enum ccan_device_reg reg, u32 val);
+ struct clk *can_clk;
+ struct clk *host_clk;
+ struct clk *timer_clk;
+ u32 tx_mode;
+ struct reset_control *resets;
+ u32 cantype;
+ bool is_starfive;
+};
+
+struct cast_can_data {
+ enum cast_can_type cantype;
+ const struct can_bittiming_const *bittime_const;
+ int (*starfive_parse_dt)(struct ccan_priv *priv);
+};
+
+static struct can_bittiming_const ccan_bittiming_const = {
+ .name = DRIVER_NAME,
+ .tseg1_min = 2,
+ .tseg1_max = 16,
+ .tseg2_min = 2,
+ .tseg2_max = 8,
+ .sjw_max = 4,
+ .brp_min = 1,
+ .brp_max = 256,
+ .brp_inc = 1,
+};
+
+static struct can_bittiming_const ccan_bittiming_const_canfd = {
+ .name = DRIVER_NAME,
+ .tseg1_min = 2,
+ .tseg1_max = 64,
+ .tseg2_min = 2,
+ .tseg2_max = 16,
+ .sjw_max = 16,
+ .brp_min = 1,
+ .brp_max = 256,
+ .brp_inc = 1,
+};
+
+static struct can_bittiming_const ccan_data_bittiming_const_canfd = {
+ .name = DRIVER_NAME,
+ .tseg1_min = 1,
+ .tseg1_max = 16,
+ .tseg2_min = 2,
+ .tseg2_max = 8,
+ .sjw_max = 8,
+ .brp_min = 1,
+ .brp_max = 256,
+ .brp_inc = 1,
+};
+
+static void ccan_write_reg_le(const struct ccan_priv *priv,
+ enum ccan_device_reg reg, u32 val)
+{
+ iowrite32(val, priv->reg_base + reg);
+}
+
+static u32 ccan_read_reg_le(const struct ccan_priv *priv,
+ enum ccan_device_reg reg)
+{
+ return ioread32(priv->reg_base + reg);
+}
+
+static inline unsigned char ccan_ioread8(const void *addr)
+{
+ void *addr_down;
+ union val {
+ u8 val_8[4];
+ u32 val_32;
+ } val;
+ u32 offset = 0;
+
+ addr_down = (void *)ALIGN_DOWN((unsigned long)addr, 4);
+ offset = addr - addr_down;
+ val.val_32 = ioread32(addr_down);
+
+ return val.val_8[offset];
+}
+
+static inline void ccan_iowrite8(unsigned char value, void *addr)
+{
+ void *addr_down;
+ union val {
+ u8 val_8[4];
+ u32 val_32;
+ } val;
+ u8 offset = 0;
+
+ addr_down = (void *)ALIGN_DOWN((unsigned long)addr, 4);
+ offset = addr - addr_down;
+ val.val_32 = ioread32(addr_down);
+ val.val_8[offset] = value;
+ iowrite32(val.val_32, addr_down);
+}
+
+static void ccan_reigister_set_bit(const struct ccan_priv *priv,
+ enum ccan_device_reg reg,
+ enum ccan_reg_bitchange mask)
+{
+ void *addr_down;
+ union val {
+ u8 val_8[4];
+ u32 val_32;
+ } val;
+ u8 offset = 0;
+
+ addr_down = (void *)ALIGN_DOWN((unsigned long)(priv->reg_base + reg), 4);
+ offset = (priv->reg_base + reg) - addr_down;
+ val.val_32 = ioread32(addr_down);
+ val.val_8[offset] |= mask;
+ iowrite32(val.val_32, addr_down);
+}
+
+static void ccan_reigister_off_bit(const struct ccan_priv *priv,
+ enum ccan_device_reg reg,
+ enum ccan_reg_bitchange mask)
+{
+ void *addr_down;
+ union val {
+ u8 val_8[4];
+ u32 val_32;
+ } val;
+ u8 offset = 0;
+
+ addr_down = (void *)ALIGN_DOWN((unsigned long)(priv->reg_base + reg), 4);
+ offset = (priv->reg_base + reg) - addr_down;
+ val.val_32 = ioread32(addr_down);
+ val.val_8[offset] &= mask;
+ iowrite32(val.val_32, addr_down);
+}
+
+static int ccan_device_driver_bittime_configuration(struct net_device *ndev)
+{
+ struct ccan_priv *priv = netdev_priv(ndev);
+ struct can_bittiming *bt = &priv->can.bittiming;
+ struct can_bittiming *dbt = &priv->can.data_bittiming;
+ u32 reset_test, bittiming_temp, data_bittiming;
+
+ reset_test = ccan_ioread8(priv->reg_base + CCAN_CFG_STAT_OFFSET);
+
+ if (!(reset_test & CCAN_SET_RST_MASK)) {
+ netdev_alert(ndev, "Not in reset mode, cannot set bit timing\n");
+ return -EPERM;
+ }
+
+ bittiming_temp = ((bt->phase_seg1 + bt->prop_seg + 1 - 2) << SEG_1_SHIFT) |
+ ((bt->phase_seg2 - 1) << SEG_2_SHIFT) |
+ ((bt->sjw - 1) << SJW_SHIFT) |
+ ((bt->brp - 1) << PRESC_SHIFT);
+
+ /* Check the bittime parameter */
+ if ((((int)(bt->phase_seg1 + bt->prop_seg + 1) - 2) < 0) ||
+ (((int)(bt->phase_seg2) - 1) < 0) ||
+ (((int)(bt->sjw) - 1) < 0) ||
+ (((int)(bt->brp) - 1) < 0))
+ return -EINVAL;
+
+ priv->write_reg(priv, CCAN_S_SEG_1_OFFSET, bittiming_temp);
+
+ if (priv->cantype == CAST_CAN_TYPE_CANFD) {
+ data_bittiming = ((dbt->phase_seg1 + dbt->prop_seg + 1 - 2) << SEG_1_SHIFT) |
+ ((dbt->phase_seg2 - 1) << SEG_2_SHIFT) |
+ ((dbt->sjw - 1) << SJW_SHIFT) |
+ ((dbt->brp - 1) << PRESC_SHIFT);
+
+ if ((((int)(dbt->phase_seg1 + dbt->prop_seg + 1) - 2) < 0) ||
+ (((int)(dbt->phase_seg2) - 1) < 0) ||
+ (((int)(dbt->sjw) - 1) < 0) ||
+ (((int)(dbt->brp) - 1) < 0))
+ return -EINVAL;
+
+ priv->write_reg(priv, CCAN_F_SEG_1_OFFSET, data_bittiming);
+ }
+
+ ccan_reigister_off_bit(priv, CCAN_CFG_STAT_OFFSET, CCAN_OFF_RST_MASK);
+
+ netdev_dbg(ndev, "Slow bit rate: %08x\n", priv->read_reg(priv, CCAN_S_SEG_1_OFFSET));
+ netdev_dbg(ndev, "Fast bit rate: %08x\n", priv->read_reg(priv, CCAN_F_SEG_1_OFFSET));
+
+ return 0;
+}
+
+int ccan_get_freebuffer(struct ccan_priv *priv)
+{
+ /* Get next transmit buffer */
+ ccan_reigister_set_bit(priv, CCAN_TCTRL_OFFSET, CCAN_SET_TENEXT_MASK);
+
+ if (ccan_ioread8(priv->reg_base + CCAN_TCTRL_OFFSET) & CCAN_SET_TENEXT_MASK)
+ return -EPERM;
+
+ return 0;
+}
+
+static void ccan_tx_interrupt(struct net_device *ndev, u8 isr)
+{
+ struct ccan_priv *priv = netdev_priv(ndev);
+
+ /* wait till transmission of the PTB or STB finished */
+ while (isr & (CCAN_SET_TPIF_MASK | CCAN_SET_TSIF_MASK)) {
+ if (isr & CCAN_SET_TPIF_MASK)
+ ccan_reigister_set_bit(priv, CCAN_RTIF_OFFSET, CCAN_SET_TPIF_MASK);
+
+ if (isr & CCAN_SET_TSIF_MASK)
+ ccan_reigister_set_bit(priv, CCAN_RTIF_OFFSET, CCAN_SET_TSIF_MASK);
+
+ isr = ccan_ioread8(priv->reg_base + CCAN_RTIF_OFFSET);
+ }
+ netif_wake_queue(ndev);
+}
+
+static int ccan_rx(struct net_device *ndev)
+{
+ struct ccan_priv *priv = netdev_priv(ndev);
+ struct net_device_stats *stats = &ndev->stats;
+ struct can_frame *cf;
+ struct sk_buff *skb;
+ u32 can_id;
+ u8 dlc, control, rx_status;
+
+ rx_status = ccan_ioread8(priv->reg_base + CCAN_RCTRL_OFFSET);
+
+ if (!(rx_status & CCAN_RSTAT_NOT_EMPTY_MASK))
+ return 0;
+
+ control = ccan_ioread8(priv->reg_base + CCAN_RBUF_CTL_OFFSET);
+ can_id = priv->read_reg(priv, CCAN_RUBF_ID_OFFSET);
+ dlc = ccan_ioread8(priv->reg_base + CCAN_RBUF_CTL_OFFSET) & CCAN_SET_DLC_MASK;
+
+ skb = alloc_can_skb(ndev, (struct can_frame **)&cf);
+ if (!skb) {
+ stats->rx_dropped++;
+ return 0;
+ }
+ cf->can_dlc = can_cc_dlc2len(dlc);
+
+ /* change the CANFD id into socketcan id format */
+ cf->can_id = can_id;
+ if (control & CCAN_SET_IDE_MASK)
+ cf->can_id |= CAN_EFF_FLAG;
+ else
+ cf->can_id &= ~CAN_EFF_FLAG;
+
+ if (control & CCAN_SET_RTR_MASK)
+ cf->can_id |= CAN_RTR_FLAG;
+
+ if (!(control & CCAN_SET_RTR_MASK)) {
+ *((u32 *)(cf->data + 0)) = priv->read_reg(priv, CCAN_RBUF_DATA_OFFSET);
+ *((u32 *)(cf->data + 4)) = priv->read_reg(priv, CCAN_RBUF_DATA_OFFSET + 4);
+ }
+
+ ccan_reigister_set_bit(priv, CCAN_RCTRL_OFFSET, CCAN_SET_RREL_MASK);
+ stats->rx_bytes += can_fd_dlc2len(cf->can_dlc);
+ stats->rx_packets++;
+ netif_receive_skb(skb);
+
+ return 1;
+}
+
+static int ccanfd_rx(struct net_device *ndev)
+{
+ struct ccan_priv *priv = netdev_priv(ndev);
+ struct net_device_stats *stats = &ndev->stats;
+ struct canfd_frame *cf;
+ struct sk_buff *skb;
+ u32 can_id;
+ u8 dlc, control, rx_status;
+ int i;
+
+ rx_status = ccan_ioread8(priv->reg_base + CCAN_RCTRL_OFFSET);
+
+ if (!(rx_status & CCAN_RSTAT_NOT_EMPTY_MASK))
+ return 0;
+
+ control = ccan_ioread8(priv->reg_base + CCAN_RBUF_CTL_OFFSET);
+ can_id = priv->read_reg(priv, CCAN_RUBF_ID_OFFSET);
+ dlc = ccan_ioread8(priv->reg_base + CCAN_RBUF_CTL_OFFSET) & CCAN_SET_DLC_MASK;
+
+ if (control & CCAN_SET_EDL_MASK)
+ /* allocate sk_buffer for canfd frame */
+ skb = alloc_canfd_skb(ndev, &cf);
+ else
+ /* allocate sk_buffer for can frame */
+ skb = alloc_can_skb(ndev, (struct can_frame **)&cf);
+
+ if (!skb) {
+ stats->rx_dropped++;
+ return 0;
+ }
+
+ /* change the CANFD or CAN2.0 data into socketcan data format */
+ if (control & CCAN_SET_EDL_MASK)
+ cf->len = can_fd_dlc2len(dlc);
+ else
+ cf->len = can_cc_dlc2len(dlc);
+
+ /* change the CANFD id into socketcan id format */
+ cf->can_id = can_id;
+ if (control & CCAN_SET_IDE_MASK)
+ cf->can_id |= CAN_EFF_FLAG;
+ else
+ cf->can_id &= ~CAN_EFF_FLAG;
+
+ if (!(control & CCAN_SET_EDL_MASK))
+ if (control & CCAN_SET_RTR_MASK)
+ cf->can_id |= CAN_RTR_FLAG;
+
+ /* CANFD frames handed over to SKB */
+ if (control & CCAN_SET_EDL_MASK) {
+ for (i = 0; i < cf->len; i += 4)
+ *((u32 *)(cf->data + i)) = priv->read_reg(priv, CCAN_RBUF_DATA_OFFSET + i);
+ } else {
+ /* skb reads the received datas, if the RTR bit not set */
+ if (!(control & CCAN_SET_RTR_MASK)) {
+ *((u32 *)(cf->data + 0)) = priv->read_reg(priv, CCAN_RBUF_DATA_OFFSET);
+ *((u32 *)(cf->data + 4)) = priv->read_reg(priv, CCAN_RBUF_DATA_OFFSET + 4);
+ }
+ }
+
+ ccan_reigister_set_bit(priv, CCAN_RCTRL_OFFSET, CCAN_SET_RREL_MASK);
+
+ stats->rx_bytes += cf->len;
+ stats->rx_packets++;
+ netif_receive_skb(skb);
+
+ return 1;
+}
+
+static int ccan_rx_poll(struct napi_struct *napi, int quota)
+{
+ struct net_device *ndev = napi->dev;
+ struct ccan_priv *priv = netdev_priv(ndev);
+ int work_done = 0;
+ u8 rx_status = 0, control = 0;
+
+ control = ccan_ioread8(priv->reg_base + CCAN_RBUF_CTL_OFFSET);
+ rx_status = ccan_ioread8(priv->reg_base + CCAN_RCTRL_OFFSET);
+
+ /* clear receive interrupt and deal with all the received frames */
+ while ((rx_status & CCAN_RSTAT_NOT_EMPTY_MASK) && (work_done < quota)) {
+ if (control & CCAN_SET_EDL_MASK)
+ work_done += ccanfd_rx(ndev);
+ else
+ work_done += ccan_rx(ndev);
+
+ control = ccan_ioread8(priv->reg_base + CCAN_RBUF_CTL_OFFSET);
+ rx_status = ccan_ioread8(priv->reg_base + CCAN_RCTRL_OFFSET);
+ }
+
+ napi_complete(napi);
+ ccan_reigister_set_bit(priv, CCAN_RTIE_OFFSET, CCAN_SET_RIE_MASK);
+
+ return work_done;
+}
+
+static void ccan_rxfull_interrupt(struct net_device *ndev, u8 isr)
+{
+ struct ccan_priv *priv = netdev_priv(ndev);
+
+ if (isr & CCAN_SET_RAFIF_MASK)
+ ccan_reigister_set_bit(priv, CCAN_RTIF_OFFSET, CCAN_SET_RAFIF_MASK);
+
+ if (isr & (CCAN_SET_RAFIF_MASK | CCAN_SET_RFIF_MASK))
+ ccan_reigister_set_bit(priv, CCAN_RTIF_OFFSET,
+ (CCAN_SET_RAFIF_MASK | CCAN_SET_RFIF_MASK));
+}
+
+static int set_ccan_xmit_mode(struct net_device *ndev)
+{
+ struct ccan_priv *priv = netdev_priv(ndev);
+
+ switch (priv->tx_mode) {
+ case XMIT_FULL:
+ ccan_reigister_set_bit(priv, CCAN_TCTRL_OFFSET, CCAN_SET_FULLCAN_MASK);
+ break;
+ case XMIT_SEP_FIFO:
+ ccan_reigister_off_bit(priv, CCAN_TCTRL_OFFSET, CCAN_OFF_FULLCAN_MASK);
+ ccan_reigister_set_bit(priv, CCAN_TCTRL_OFFSET, CCAN_SET_FIFO_MASK);
+ ccan_reigister_off_bit(priv, CCAN_TCMD_OFFSET, CCAN_SET_TBSEL_MASK);
+ break;
+ case XMIT_SEP_PRIO:
+ ccan_reigister_off_bit(priv, CCAN_TCTRL_OFFSET, CCAN_OFF_FULLCAN_MASK);
+ ccan_reigister_off_bit(priv, CCAN_TCTRL_OFFSET, CCAN_OFF_FIFO_MASK);
+ ccan_reigister_off_bit(priv, CCAN_TCMD_OFFSET, CCAN_SET_TBSEL_MASK);
+ break;
+ case XMIT_PTB_MODE:
+ ccan_reigister_off_bit(priv, CCAN_TCMD_OFFSET, CCAN_OFF_TBSEL_MASK);
+ break;
+ default:
+ break;
+ }
+ return 0;
+}
+
+static netdev_tx_t ccan_driver_start_xmit(struct sk_buff *skb, struct net_device *ndev)
+{
+ struct ccan_priv *priv = netdev_priv(ndev);
+ struct canfd_frame *cf = (struct canfd_frame *)skb->data;
+ struct net_device_stats *stats = &ndev->stats;
+ u32 ttsen, id, ctl, addr_off;
+ int i;
+
+ priv->tx_mode = XMIT_PTB_MODE;
+
+ if (can_dropped_invalid_skb(ndev, skb))
+ return NETDEV_TX_OK;
+
+ switch (priv->tx_mode) {
+ case XMIT_FULL:
+ return NETDEV_TX_BUSY;
+ case XMIT_PTB_MODE:
+ set_ccan_xmit_mode(ndev);
+ ccan_reigister_off_bit(priv, CCAN_TCMD_OFFSET, CCAN_OFF_STBY_MASK);
+
+ if (cf->can_id & CAN_EFF_FLAG) {
+ id = cf->can_id & CAN_EFF_MASK;
+ ttsen = 0 << TTSEN_8_32_SHIFT;
+ id |= ttsen;
+ } else {
+ id = cf->can_id & CAN_SFF_MASK;
+ ttsen = 0 << TTSEN_8_32_SHIFT;
+ id |= ttsen;
+ }
+
+ ctl = can_fd_len2dlc(cf->len);
+
+ /* transmit can fd frame */
+ if (priv->cantype == CAST_CAN_TYPE_CANFD) {
+ if (can_is_canfd_skb(skb)) {
+ if (cf->can_id & CAN_EFF_FLAG)
+ ctl |= CCAN_SET_IDE_MASK;
+ else
+ ctl &= CCAN_OFF_IDE_MASK;
+
+ if (cf->flags & CANFD_BRS)
+ ctl |= CCAN_SET_BRS_MASK;
+
+ ctl |= CCAN_SET_EDL_MASK;
+
+ addr_off = CCAN_TBUF_DATA_OFFSET;
+
+ for (i = 0; i < cf->len; i += 4) {
+ priv->write_reg(priv, addr_off,
+ *((u32 *)(cf->data + i)));
+ addr_off += 4;
+ }
+ } else {
+ ctl &= (CCAN_OFF_EDL_MASK | CCAN_OFF_BRS_MASK);
+
+ if (cf->can_id & CAN_EFF_FLAG)
+ ctl |= CCAN_SET_IDE_MASK;
+ else
+ ctl &= CCAN_OFF_IDE_MASK;
+
+ if (cf->can_id & CAN_RTR_FLAG) {
+ ctl |= CCAN_SET_RTR_MASK;
+ priv->write_reg(priv,
+ CCAN_TBUF_ID_OFFSET, id);
+ priv->write_reg(priv,
+ CCAN_TBUF_CTL_OFFSET, ctl);
+ } else {
+ ctl &= CCAN_OFF_RTR_MASK;
+ addr_off = CCAN_TBUF_DATA_OFFSET;
+ priv->write_reg(priv, addr_off,
+ *((u32 *)(cf->data + 0)));
+ priv->write_reg(priv, addr_off + 4,
+ *((u32 *)(cf->data + 4)));
+ }
+ }
+ priv->write_reg(priv, CCAN_TBUF_ID_OFFSET, id);
+ priv->write_reg(priv, CCAN_TBUF_CTL_OFFSET, ctl);
+ addr_off = CCAN_TBUF_DATA_OFFSET;
+ } else {
+ ctl &= (CCAN_OFF_EDL_MASK | CCAN_OFF_BRS_MASK);
+
+ if (cf->can_id & CAN_EFF_FLAG)
+ ctl |= CCAN_SET_IDE_MASK;
+ else
+ ctl &= CCAN_OFF_IDE_MASK;
+
+ if (cf->can_id & CAN_RTR_FLAG) {
+ ctl |= CCAN_SET_RTR_MASK;
+ priv->write_reg(priv, CCAN_TBUF_ID_OFFSET, id);
+ priv->write_reg(priv, CCAN_TBUF_CTL_OFFSET, ctl);
+ } else {
+ ctl &= CCAN_OFF_RTR_MASK;
+ priv->write_reg(priv, CCAN_TBUF_ID_OFFSET, id);
+ priv->write_reg(priv, CCAN_TBUF_CTL_OFFSET, ctl);
+ addr_off = CCAN_TBUF_DATA_OFFSET;
+ priv->write_reg(priv, addr_off,
+ *((u32 *)(cf->data + 0)));
+ priv->write_reg(priv, addr_off + 4,
+ *((u32 *)(cf->data + 4)));
+ }
+ }
+ ccan_reigister_set_bit(priv, CCAN_TCMD_OFFSET, CCAN_SET_TPE_MASK);
+ stats->tx_bytes += cf->len;
+ break;
+ default:
+ break;
+ }
+
+ if (!(ndev->flags & IFF_ECHO) || (skb->protocol != htons(ETH_P_CAN) &&
+ skb->protocol != htons(ETH_P_CANFD))) {
+ kfree_skb(skb);
+ return 0;
+ }
+
+ skb = can_create_echo_skb(skb);
+ if (!skb)
+ return -ENOMEM;
+
+ /* make settings for echo to reduce code in irq context */
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+ skb->dev = ndev;
+
+ skb_tx_timestamp(skb);
+
+ return NETDEV_TX_OK;
+}
+
+static int set_reset_mode(struct net_device *ndev)
+{
+ struct ccan_priv *priv = netdev_priv(ndev);
+ u8 ret;
+
+ ret = ccan_ioread8(priv->reg_base + CCAN_CFG_STAT_OFFSET);
+ ret |= CCAN_SET_RST_MASK;
+ ccan_iowrite8(ret, priv->reg_base + CCAN_CFG_STAT_OFFSET);
+
+ return 0;
+}
+
+static void ccan_driver_stop(struct net_device *ndev)
+{
+ struct ccan_priv *priv = netdev_priv(ndev);
+ int ret;
+
+ ret = set_reset_mode(ndev);
+ if (ret)
+ netdev_err(ndev, "Mode resetting failed!\n");
+
+ priv->can.state = CAN_STATE_STOPPED;
+}
+
+static int ccan_driver_close(struct net_device *ndev)
+{
+ struct ccan_priv *priv = netdev_priv(ndev);
+
+ netif_stop_queue(ndev);
+ napi_disable(&priv->napi);
+ ccan_driver_stop(ndev);
+
+ close_candev(ndev);
+
+ return 0;
+}
+
+static enum can_state get_of_chip_status(struct net_device *ndev)
+{
+ struct ccan_priv *priv = netdev_priv(ndev);
+ u8 can_stat, eir;
+
+ can_stat = ccan_ioread8(priv->reg_base + CCAN_CFG_STAT_OFFSET);
+ eir = ccan_ioread8(priv->reg_base + CCAN_ERRINT_OFFSET);
+
+ if (can_stat & CCAN_SET_BUSOFF_MASK)
+ return CAN_STATE_BUS_OFF;
+
+ if ((eir & CCAN_SET_EPASS_MASK) && ~(can_stat & CCAN_SET_BUSOFF_MASK))
+ return CAN_STATE_ERROR_PASSIVE;
+
+ if (eir & CCAN_SET_EWARN_MASK && ~(eir & CCAN_SET_EPASS_MASK))
+ return CAN_STATE_ERROR_WARNING;
+
+ if (~(eir & CCAN_SET_EPASS_MASK))
+ return CAN_STATE_ERROR_ACTIVE;
+
+ return CAN_STATE_ERROR_ACTIVE;
+}
+
+static void ccan_error_interrupt(struct net_device *ndev, u8 isr, u8 eir)
+{
+ struct ccan_priv *priv = netdev_priv(ndev);
+ struct net_device_stats *stats = &ndev->stats;
+ struct can_frame *cf;
+ struct sk_buff *skb;
+ u8 koer, recnt = 0, tecnt = 0, can_stat = 0;
+
+ skb = alloc_can_err_skb(ndev, &cf);
+
+ koer = ccan_ioread8(priv->reg_base + CCAN_EALCAP_OFFSET) & CCAN_SET_KOER_MASK;
+ recnt = ccan_ioread8(priv->reg_base + CCAN_RECNT_OFFSET);
+ tecnt = ccan_ioread8(priv->reg_base + CCAN_TECNT_OFFSET);
+
+ /*Read can status*/
+ can_stat = ccan_ioread8(priv->reg_base + CCAN_CFG_STAT_OFFSET);
+
+ /* Bus off --->active error mode */
+ if ((isr & CCAN_SET_EIF_MASK) && priv->can.state == CAN_STATE_BUS_OFF)
+ priv->can.state = get_of_chip_status(ndev);
+
+ /* State selection */
+ if (can_stat & CCAN_SET_BUSOFF_MASK) {
+ priv->can.state = get_of_chip_status(ndev);
+ priv->can.can_stats.bus_off++;
+ ccan_reigister_set_bit(priv, CCAN_CFG_STAT_OFFSET, CCAN_SET_BUSOFF_MASK);
+ can_bus_off(ndev);
+ if (skb)
+ cf->can_id |= CAN_ERR_BUSOFF;
+
+ } else if ((eir & CCAN_SET_EPASS_MASK) && ~(can_stat & CCAN_SET_BUSOFF_MASK)) {
+ priv->can.state = get_of_chip_status(ndev);
+ priv->can.can_stats.error_passive++;
+ if (skb) {
+ cf->can_id |= CAN_ERR_CRTL;
+ cf->data[1] |= (recnt > 127) ? CAN_ERR_CRTL_RX_PASSIVE : 0;
+ cf->data[1] |= (tecnt > 127) ? CAN_ERR_CRTL_TX_PASSIVE : 0;
+ cf->data[6] = tecnt;
+ cf->data[7] = recnt;
+ }
+ } else if (eir & CCAN_SET_EWARN_MASK && ~(eir & CCAN_SET_EPASS_MASK)) {
+ priv->can.state = get_of_chip_status(ndev);
+ priv->can.can_stats.error_warning++;
+ if (skb) {
+ cf->can_id |= CAN_ERR_CRTL;
+ cf->data[1] |= (recnt > 95) ? CAN_ERR_CRTL_RX_WARNING : 0;
+ cf->data[1] |= (tecnt > 95) ? CAN_ERR_CRTL_TX_WARNING : 0;
+ cf->data[6] = tecnt;
+ cf->data[7] = recnt;
+ }
+ }
+
+ /* Check for in protocol defined error interrupt */
+ if (eir & CCAN_SET_BEIF_MASK) {
+ if (skb)
+ cf->can_id |= CAN_ERR_BUSERROR | CAN_ERR_PROT;
+
+ if (koer == CCAN_SET_BIT_ERROR_MASK) {
+ stats->tx_errors++;
+ if (skb)
+ cf->data[2] = CAN_ERR_PROT_BIT;
+ } else if (koer == CCAN_SET_FORM_ERROR_MASK) {
+ stats->rx_errors++;
+ if (skb)
+ cf->data[2] = CAN_ERR_PROT_FORM;
+ } else if (koer == CCAN_SET_STUFF_ERROR_MASK) {
+ stats->rx_errors++;
+ if (skb)
+ cf->data[3] = CAN_ERR_PROT_STUFF;
+ } else if (koer == CCAN_SET_ACK_ERROR_MASK) {
+ stats->tx_errors++;
+ if (skb)
+ cf->data[2] = CAN_ERR_PROT_LOC_ACK;
+ } else if (koer == CCAN_SET_CRC_ERROR_MASK) {
+ stats->rx_errors++;
+ if (skb)
+ cf->data[2] = CAN_ERR_PROT_LOC_CRC_SEQ;
+ }
+ priv->can.can_stats.bus_error++;
+ }
+
+ if (skb) {
+ stats->rx_packets++;
+ stats->rx_bytes += cf->can_dlc;
+ netif_rx(skb);
+ }
+
+ netdev_dbg(ndev, "Recnt is 0x%02x", ccan_ioread8(priv->reg_base + CCAN_RECNT_OFFSET));
+ netdev_dbg(ndev, "Tecnt is 0x%02x", ccan_ioread8(priv->reg_base + CCAN_TECNT_OFFSET));
+}
+
+static irqreturn_t ccan_interrupt(int irq, void *dev_id)
+{
+ struct net_device *ndev = (struct net_device *)dev_id;
+ struct ccan_priv *priv = netdev_priv(ndev);
+ u8 isr, eir;
+ u8 isr_handled = 0, eir_handled = 0;
+
+ /* read the value of interrupt status register */
+ isr = ccan_ioread8(priv->reg_base + CCAN_RTIF_OFFSET);
+
+ /* read the value of error interrupt register */
+ eir = ccan_ioread8(priv->reg_base + CCAN_ERRINT_OFFSET);
+
+ /* Check for Tx interrupt and Processing it */
+ if (isr & (CCAN_SET_TPIF_MASK | CCAN_SET_TSIF_MASK)) {
+ ccan_tx_interrupt(ndev, isr);
+ isr_handled |= (CCAN_SET_TPIF_MASK | CCAN_SET_TSIF_MASK);
+ }
+
+ if (isr & (CCAN_SET_RAFIF_MASK | CCAN_SET_RFIF_MASK)) {
+ ccan_rxfull_interrupt(ndev, isr);
+ isr_handled |= (CCAN_SET_RAFIF_MASK | CCAN_SET_RFIF_MASK);
+ }
+
+ /* Check Rx interrupt and Processing the receive interrupt routine */
+ if (isr & CCAN_SET_RIF_MASK) {
+ ccan_reigister_off_bit(priv, CCAN_RTIE_OFFSET, CCAN_OFF_RIE_MASK);
+ ccan_reigister_set_bit(priv, CCAN_RTIF_OFFSET, CCAN_SET_RIF_MASK);
+
+ napi_schedule(&priv->napi);
+ isr_handled |= CCAN_SET_RIF_MASK;
+ }
+
+ if ((isr & CCAN_SET_EIF_MASK) |
+ (eir & (CCAN_SET_EPIF_MASK | CCAN_SET_BEIF_MASK))) {
+ /* reset EPIF and BEIF. Reset EIF */
+ ccan_reigister_set_bit(priv, CCAN_ERRINT_OFFSET,
+ eir & (CCAN_SET_EPIF_MASK | CCAN_SET_BEIF_MASK));
+ ccan_reigister_set_bit(priv, CCAN_RTIF_OFFSET,
+ isr & CCAN_SET_EIF_MASK);
+
+ ccan_error_interrupt(ndev, isr, eir);
+
+ isr_handled |= CCAN_SET_EIF_MASK;
+ eir_handled |= (CCAN_SET_EPIF_MASK | CCAN_SET_BEIF_MASK);
+ }
+
+ if (isr_handled == 0 && eir_handled == 0) {
+ netdev_err(ndev, "Unhandled interrupt!\n");
+ return IRQ_NONE;
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int ccan_chip_start(struct net_device *ndev)
+{
+ struct ccan_priv *priv = netdev_priv(ndev);
+ int err;
+ u8 ret;
+
+ err = set_reset_mode(ndev);
+ if (err) {
+ netdev_err(ndev, "Mode resetting failed!\n");
+ return err;
+ }
+
+ err = ccan_device_driver_bittime_configuration(ndev);
+ if (err) {
+ netdev_err(ndev, "Bittime setting failed!\n");
+ return err;
+ }
+
+ /* Set Almost Full Warning Limit */
+ ccan_reigister_set_bit(priv, CCAN_LIMIT_OFFSET, CCAN_SET_AFWL_MASK);
+
+ /* Programmable Error Warning Limit = (EWL+1)*8. Set EWL=11->Error Warning=96 */
+ ccan_reigister_set_bit(priv, CCAN_LIMIT_OFFSET, CCAN_SET_EWL_MASK);
+
+ /* Interrupts enable */
+ ccan_iowrite8(CCAN_INTR_ALL_MASK, priv->reg_base + CCAN_RTIE_OFFSET);
+
+ /* Error Interrupts enable(Error Passive and Bus Error) */
+ ccan_reigister_set_bit(priv, CCAN_ERRINT_OFFSET, CCAN_SET_EPIE_MASK);
+
+ ret = ccan_ioread8(priv->reg_base + CCAN_CFG_STAT_OFFSET);
+
+ /* Check whether it is loopback mode or normal mode */
+ if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
+ ret |= CCAN_LBMIMOD_MASK;
+ else
+ ret &= ~(CCAN_LBMEMOD_MASK | CCAN_LBMIMOD_MASK);
+
+ ccan_iowrite8(ret, priv->reg_base + CCAN_CFG_STAT_OFFSET);
+
+ priv->can.state = CAN_STATE_ERROR_ACTIVE;
+
+ return 0;
+}
+
+static int ccan_do_set_mode(struct net_device *ndev, enum can_mode mode)
+{
+ int ret;
+
+ switch (mode) {
+ case CAN_MODE_START:
+ ret = ccan_chip_start(ndev);
+ if (ret) {
+ netdev_err(ndev, "Could not start CAN device !\n");
+ return ret;
+ }
+ netif_wake_queue(ndev);
+ break;
+ default:
+ ret = -EOPNOTSUPP;
+ break;
+ }
+
+ return ret;
+}
+
+static int ccan_driver_open(struct net_device *ndev)
+{
+ struct ccan_priv *priv = netdev_priv(ndev);
+ int ret;
+
+ /* Set chip into reset mode */
+ ret = set_reset_mode(ndev);
+ if (ret) {
+ netdev_err(ndev, "Mode resetting failed!\n");
+ return ret;
+ }
+
+ /* Common open */
+ ret = open_candev(ndev);
+ if (ret)
+ return ret;
+
+ /* Register interrupt handler */
+ ret = devm_request_irq(priv->dev, ndev->irq, ccan_interrupt, IRQF_SHARED,
+ ndev->name, ndev);
+ if (ret) {
+ netdev_err(ndev, "Request_irq err: %d\n", ret);
+ goto err;
+ }
+
+ ret = ccan_chip_start(ndev);
+ if (ret) {
+ netdev_err(ndev, "Could not start CAN device !\n");
+ goto err;
+ }
+
+ napi_enable(&priv->napi);
+ netif_start_queue(ndev);
+
+ return 0;
+
+err:
+ close_candev(ndev);
+ return ret;
+}
+
+static int ccan_starfive_parse_dt(struct ccan_priv *priv)
+{
+ struct of_phandle_args args;
+ u32 syscon_mask, syscon_shift;
+ u32 syscon_offset, regval;
+ int ret;
+
+ ret = of_parse_phandle_with_fixed_args(priv->dev->of_node,
+ "starfive,sys-syscon", 3, 0, &args);
+ if (ret) {
+ dev_err(priv->dev, "Failed to parse starfive,sys-syscon\n");
+ return -EINVAL;
+ }
+
+ priv->reg_syscon = syscon_node_to_regmap(args.np);
+ of_node_put(args.np);
+ if (IS_ERR(priv->reg_syscon))
+ return PTR_ERR(priv->reg_syscon);
+
+ syscon_offset = args.args[0];
+ syscon_shift = args.args[1];
+ syscon_mask = args.args[2];
+
+ /* enable can2.0/canfd function */
+ regval = priv->cantype << syscon_shift;
+ ret = regmap_update_bits(priv->reg_syscon, syscon_offset, syscon_mask, regval);
+ if (ret)
+ return ret;
+
+ priv->is_starfive = true;
+
+ return 0;
+}
+
+static const struct net_device_ops ccan_netdev_ops = {
+ .ndo_open = ccan_driver_open,
+ .ndo_stop = ccan_driver_close,
+ .ndo_start_xmit = ccan_driver_start_xmit,
+ .ndo_change_mtu = can_change_mtu,
+};
+
+static const struct cast_can_data ccan_can_data = {
+ .cantype = CAST_CAN_TYPE_CAN,
+ .bittime_const = &ccan_bittiming_const,
+};
+
+static const struct cast_can_data ccan_canfd_data = {
+ .cantype = CAST_CAN_TYPE_CANFD,
+ .bittime_const = &ccan_bittiming_const_canfd,
+};
+
+static const struct cast_can_data sfcan_can_data = {
+ .cantype = CAST_CAN_TYPE_CAN,
+ .bittime_const = &ccan_bittiming_const,
+ .starfive_parse_dt = ccan_starfive_parse_dt,
+};
+
+static const struct of_device_id ccan_of_match[] = {
+ { .compatible = "cast,can", .data = &ccan_can_data },
+ { .compatible = "cast,canfd", .data = &ccan_canfd_data },
+ { .compatible = "starfive,can", .data = &sfcan_can_data },
+ { /* end of list */ },
+};
+MODULE_DEVICE_TABLE(of, ccan_of_match);
+
+static int ccan_driver_probe(struct platform_device *pdev)
+{
+ struct net_device *ndev;
+ struct ccan_priv *priv;
+ const struct of_device_id *id;
+ const struct cast_can_data *ddata;
+ void __iomem *addr;
+ int ret;
+
+ addr = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(addr)) {
+ ret = PTR_ERR(addr);
+ goto exit;
+ }
+
+ id = of_match_device(ccan_of_match, &pdev->dev);
+ if (id && id->data)
+ ddata = id->data;
+
+ ndev = alloc_candev(sizeof(struct ccan_priv), 1);
+ if (!ndev) {
+ ret = -ENOMEM;
+ goto exit;
+ }
+
+ priv = netdev_priv(ndev);
+ priv->dev = &pdev->dev;
+ priv->is_starfive = false;
+
+ if (ddata) {
+ if (ddata->starfive_parse_dt) {
+ ret = ccan_starfive_parse_dt(priv);
+ if (ret)
+ goto free_exit;
+ }
+ }
+
+ priv->can_clk = devm_clk_get_enabled(&pdev->dev, "can_clk");
+ if (IS_ERR(priv->can_clk)) {
+ ret = dev_err_probe(&pdev->dev, PTR_ERR(priv->can_clk),
+ "Device clock not found\n");
+ goto free_exit;
+ }
+
+ priv->host_clk = devm_clk_get_enabled(&pdev->dev, "apb_clk");
+ if (IS_ERR(priv->host_clk)) {
+ ret = dev_err_probe(&pdev->dev, PTR_ERR(priv->host_clk),
+ "Host clock not found\n");
+ goto free_exit;
+ }
+
+ priv->timer_clk = devm_clk_get_enabled(&pdev->dev, "timer_clk");
+ if (IS_ERR(priv->timer_clk)) {
+ ret = dev_err_probe(&pdev->dev, PTR_ERR(priv->timer_clk),
+ "Timer clock not found\n");
+ goto free_exit;
+ }
+
+ priv->resets = devm_reset_control_array_get_exclusive(&pdev->dev);
+ if (IS_ERR(priv->resets)) {
+ ret = dev_err_probe(&pdev->dev, PTR_ERR(priv->resets),
+ "Failed to get CAN resets");
+ goto clk_exit;
+ }
+
+ ret = reset_control_deassert(priv->resets);
+ if (ret)
+ goto clk_exit;
+
+ priv->can.do_set_mode = ccan_do_set_mode;
+ priv->can.bittiming_const = ddata->bittime_const;
+ priv->cantype = ddata->cantype;
+
+ if (priv->cantype == CAST_CAN_TYPE_CANFD) {
+ priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK | CAN_CTRLMODE_FD;
+ priv->can.data_bittiming_const = &ccan_data_bittiming_const_canfd;
+ } else {
+ priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK;
+ }
+
+ priv->reg_base = addr;
+ priv->write_reg = ccan_write_reg_le;
+ priv->read_reg = ccan_read_reg_le;
+ priv->can.clock.freq = clk_get_rate(priv->can_clk);
+ ndev->irq = platform_get_irq(pdev, 0);
+
+ /* we support local echo */
+ ndev->flags |= IFF_ECHO;
+ ndev->netdev_ops = &ccan_netdev_ops;
+
+ platform_set_drvdata(pdev, ndev);
+ SET_NETDEV_DEV(ndev, &pdev->dev);
+
+ netif_napi_add_tx_weight(ndev, &priv->napi, ccan_rx_poll, 16);
+ ret = register_candev(ndev);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to register (err=%d)\n", ret);
+ goto reset_exit;
+ }
+
+ dev_dbg(&pdev->dev, "Driver registered: regs=%p, irp=%d, clock=%d\n",
+ priv->reg_base, ndev->irq, priv->can.clock.freq);
+
+ return 0;
+
+reset_exit:
+ reset_control_assert(priv->resets);
+clk_exit:
+ clk_disable_unprepare(priv->can_clk);
+ clk_disable_unprepare(priv->host_clk);
+ clk_disable_unprepare(priv->timer_clk);
+free_exit:
+ free_candev(ndev);
+exit:
+ return ret;
+}
+
+static int ccan_driver_remove(struct platform_device *pdev)
+{
+ struct net_device *ndev = platform_get_drvdata(pdev);
+ struct ccan_priv *priv = netdev_priv(ndev);
+
+ reset_control_assert(priv->resets);
+ clk_disable_unprepare(priv->can_clk);
+ clk_disable_unprepare(priv->host_clk);
+ clk_disable_unprepare(priv->timer_clk);
+
+ unregister_candev(ndev);
+ netif_napi_del(&priv->napi);
+ free_candev(ndev);
+
+ return 0;
+}
+
+static struct platform_driver ccan_driver = {
+ .probe = ccan_driver_probe,
+ .remove = ccan_driver_remove,
+ .driver = {
+ .name = DRIVER_NAME,
+ .of_match_table = ccan_of_match,
+ },
+};
+
+module_platform_driver(ccan_driver);
+
+MODULE_DESCRIPTION("CAST CAN Controller Driver");
+MODULE_AUTHOR("William Qiu<william.qiu at starfivetech.com");
+MODULE_LICENSE("GPL");
--
2.34.1
More information about the linux-riscv
mailing list