Add support for the i.MX28 EVK

This patch was originally put together in January 2011 by Roshni.

1 files changed, 361 insertions, 0 deletions

diff --git a/drivers/net/can/flexcan/mbm.c b/drivers/net/can/flexcan/mbm.c
new file mode 100644
index 000000000000..c846d97daadb
--- /dev/null
+++ b/drivers/net/can/flexcan/mbm.c
@@ -0,0 +1,361 @@
+/*
+ * Copyright 2008-2010 Freescale Semiconductor, Inc. All Rights Reserved.
+ */
+
+/*
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+/*!
+ * @file mbm.c
+ *
+ * @brief Driver for Freescale CAN Controller FlexCAN.
+ *
+ * @ingroup can
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/netdevice.h>
+#include <linux/if_arp.h>
+#include <linux/if_ether.h>
+#include <linux/platform_device.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+#include "flexcan.h"
+
+#define flexcan_swab32(x)	\
+	(((x) << 24) | ((x) >> 24) |\
+		(((x) & (__u32)0x0000ff00UL) << 8) |\
+		(((x) & (__u32)0x00ff0000UL) >> 8))
+
+static inline void flexcan_memcpy(void *dst, void *src, int len)
+{
+	int i;
+	unsigned int *d = (unsigned int *)dst, *s = (unsigned int *)src;
+	len = (len + 3) >> 2;
+	for (i = 0; i < len; i++, s++, d++)
+		*d = flexcan_swab32(*s);
+}
+
+static void flexcan_mb_bottom(struct net_device *dev, int index)
+{
+	struct flexcan_device *flexcan = netdev_priv(dev);
+	struct net_device_stats *stats = &dev->stats;
+	struct can_hw_mb *hwmb;
+	struct can_frame *frame;
+	struct sk_buff *skb;
+	unsigned int tmp;
+
+	hwmb = flexcan->hwmb + index;
+	if (flexcan->fifo || (index >= (flexcan->maxmb - flexcan->xmit_maxmb))) {
+		if ((hwmb->mb_cs & MB_CS_CODE_MASK) >> MB_CS_CODE_OFFSET ==
+							CAN_MB_TX_ABORT) {
+			hwmb->mb_cs &= ~MB_CS_CODE_MASK;
+			hwmb->mb_cs |= CAN_MB_TX_INACTIVE << MB_CS_CODE_OFFSET;
+		}
+
+		if (hwmb->mb_cs & (CAN_MB_TX_INACTIVE << MB_CS_CODE_OFFSET)) {
+			if (netif_queue_stopped(dev))
+				netif_start_queue(dev);
+			return;
+		}
+	}
+	skb = dev_alloc_skb(sizeof(struct can_frame));
+	if (skb) {
+		frame = (struct can_frame *)skb_put(skb, sizeof(*frame));
+		memset(frame, 0, sizeof(*frame));
+		if (hwmb->mb_cs & MB_CS_IDE_MASK)
+			frame->can_id =
+			    (hwmb->mb_id & CAN_EFF_MASK) | CAN_EFF_FLAG;
+		else
+			frame->can_id = (hwmb->mb_id >> 18) & CAN_SFF_MASK;
+
+		if (hwmb->mb_cs & MB_CS_RTR_MASK)
+			frame->can_id |= CAN_RTR_FLAG;
+
+		frame->can_dlc =
+		(hwmb->mb_cs & MB_CS_LENGTH_MASK) >> MB_CS_LENGTH_OFFSET;
+
+		if (frame->can_dlc && frame->can_dlc)
+			flexcan_memcpy(frame->data, hwmb->mb_data,
+				       frame->can_dlc);
+
+		if (flexcan->fifo
+		    || (index >= (flexcan->maxmb - flexcan->xmit_maxmb))) {
+			hwmb->mb_cs &= ~MB_CS_CODE_MASK;
+			hwmb->mb_cs |= CAN_MB_TX_INACTIVE << MB_CS_CODE_OFFSET;
+			if (netif_queue_stopped(dev))
+				netif_start_queue(dev);
+		}
+
+		tmp = __raw_readl(flexcan->io_base + CAN_HW_REG_TIMER);
+
+		dev->last_rx = jiffies;
+		stats->rx_packets++;
+		stats->rx_bytes += frame->can_dlc;
+
+		skb->dev = dev;
+		skb->protocol = __constant_htons(ETH_P_CAN);
+		skb->ip_summed = CHECKSUM_UNNECESSARY;
+		netif_rx(skb);
+	} else {
+		tmp = hwmb->mb_cs;
+		tmp = hwmb->mb_id;
+		tmp = hwmb->mb_data[0];
+		if (flexcan->fifo
+		    || (index >= (flexcan->maxmb - flexcan->xmit_maxmb))) {
+			hwmb->mb_cs &= ~MB_CS_CODE_MASK;
+			hwmb->mb_cs |= CAN_MB_TX_INACTIVE << MB_CS_CODE_OFFSET;
+			if (netif_queue_stopped(dev))
+				netif_start_queue(dev);
+		}
+		tmp = __raw_readl(flexcan->io_base + CAN_HW_REG_TIMER);
+		stats->rx_dropped++;
+	}
+}
+
+static void flexcan_fifo_isr(struct net_device *dev, unsigned int iflag1)
+{
+	struct flexcan_device *flexcan = dev ? netdev_priv(dev) : NULL;
+	struct net_device_stats *stats = &dev->stats;
+	struct sk_buff *skb;
+	struct can_hw_mb *hwmb = flexcan->hwmb;
+	struct can_frame *frame;
+	unsigned int tmp;
+
+	if (iflag1 & __FIFO_RDY_INT) {
+		skb = dev_alloc_skb(sizeof(struct can_frame));
+		if (skb) {
+			frame =
+			    (struct can_frame *)skb_put(skb, sizeof(*frame));
+			memset(frame, 0, sizeof(*frame));
+			if (hwmb->mb_cs & MB_CS_IDE_MASK)
+				frame->can_id =
+				    (hwmb->mb_id & CAN_EFF_MASK) | CAN_EFF_FLAG;
+			else
+				frame->can_id =
+				    (hwmb->mb_id >> 18) & CAN_SFF_MASK;
+
+			if (hwmb->mb_cs & MB_CS_RTR_MASK)
+				frame->can_id |= CAN_RTR_FLAG;
+
+			frame->can_dlc =
+				(hwmb->mb_cs & MB_CS_LENGTH_MASK) >>
+						MB_CS_LENGTH_OFFSET;
+
+			if (frame->can_dlc && (frame->can_dlc <= 8))
+				flexcan_memcpy(frame->data, hwmb->mb_data,
+					       frame->can_dlc);
+			tmp = __raw_readl(flexcan->io_base + CAN_HW_REG_TIMER);
+
+			dev->last_rx = jiffies;
+
+			stats->rx_packets++;
+			stats->rx_bytes += frame->can_dlc;
+
+			skb->dev = dev;
+			skb->protocol = __constant_htons(ETH_P_CAN);
+			skb->ip_summed = CHECKSUM_UNNECESSARY;
+			netif_rx(skb);
+		} else {
+			tmp = hwmb->mb_cs;
+			tmp = hwmb->mb_id;
+			tmp = hwmb->mb_data[0];
+			tmp = __raw_readl(flexcan->io_base + CAN_HW_REG_TIMER);
+		}
+	}
+
+	if (iflag1 & (__FIFO_OV_INT | __FIFO_WARN_INT)) {
+		skb = dev_alloc_skb(sizeof(struct can_frame));
+		if (skb) {
+			frame =
+			    (struct can_frame *)skb_put(skb, sizeof(*frame));
+			memset(frame, 0, sizeof(*frame));
+			frame->can_id = CAN_ERR_FLAG | CAN_ERR_CRTL;
+			frame->can_dlc = CAN_ERR_DLC;
+			if (iflag1 & __FIFO_WARN_INT)
+				frame->data[1] |=
+				    CAN_ERR_CRTL_TX_WARNING |
+				    CAN_ERR_CRTL_RX_WARNING;
+			if (iflag1 & __FIFO_OV_INT)
+				frame->data[1] |= CAN_ERR_CRTL_RX_OVERFLOW;
+
+			skb->dev = dev;
+			skb->protocol = __constant_htons(ETH_P_CAN);
+			skb->ip_summed = CHECKSUM_UNNECESSARY;
+			netif_rx(skb);
+		}
+	}
+}
+
+/*!
+ * @brief The function call by CAN ISR to handle mb events.
+ *
+ * @param dev		the pointer of network device.
+ *
+ * @return none
+ */
+void flexcan_mbm_isr(struct net_device *dev)
+{
+	int i, iflag1, iflag2, maxmb;
+	struct flexcan_device *flexcan = dev ? netdev_priv(dev) : NULL;
+
+	if (flexcan->maxmb > 31) {
+		maxmb = flexcan->maxmb + 1 - 32;
+		iflag1 = __raw_readl(flexcan->io_base + CAN_HW_REG_IFLAG1) &
+		    __raw_readl(flexcan->io_base + CAN_HW_REG_IMASK1);
+		iflag2 = __raw_readl(flexcan->io_base + CAN_HW_REG_IFLAG2) &
+		    __raw_readl(flexcan->io_base + CAN_HW_REG_IMASK2);
+		iflag2 &= (1 << maxmb) - 1;
+		maxmb = 32;
+	} else {
+		maxmb = flexcan->maxmb + 1;
+		iflag1 = __raw_readl(flexcan->io_base + CAN_HW_REG_IFLAG1) &
+		    __raw_readl(flexcan->io_base + CAN_HW_REG_IMASK1);
+		iflag1 &= (1 << maxmb) - 1;
+		iflag2 = 0;
+	}
+
+	__raw_writel(iflag1, flexcan->io_base + CAN_HW_REG_IFLAG1);
+	__raw_writel(iflag2, flexcan->io_base + CAN_HW_REG_IFLAG2);
+
+	if (flexcan->fifo) {
+		flexcan_fifo_isr(dev, iflag1);
+		iflag1 &= 0xFFFFFF00;
+	}
+	for (i = 0; iflag1 && (i < maxmb); i++) {
+		if (iflag1 & (1 << i)) {
+			iflag1 &= ~(1 << i);
+			flexcan_mb_bottom(dev, i);
+		}
+	}
+
+	for (i = maxmb; iflag2 && (i <= flexcan->maxmb); i++) {
+		if (iflag2 & (1 << (i - 32))) {
+			iflag2 &= ~(1 << (i - 32));
+			flexcan_mb_bottom(dev, i);
+		}
+	}
+}
+
+/*!
+ * @brief function to xmit message buffer
+ *
+ * @param flexcan	the pointer of can hardware device.
+ * @param frame		the pointer of can message frame.
+ *
+ * @return	Returns 0 if xmit is success. otherwise returns non-zero.
+ */
+int flexcan_mbm_xmit(struct flexcan_device *flexcan, struct can_frame *frame)
+{
+	int i = flexcan->xmit_mb;
+	struct can_hw_mb *hwmb = flexcan->hwmb;
+
+	do {
+		if ((hwmb[i].mb_cs & MB_CS_CODE_MASK) >> MB_CS_CODE_OFFSET ==
+							    CAN_MB_TX_INACTIVE)
+			break;
+		if ((++i) > flexcan->maxmb) {
+			if (flexcan->fifo)
+				i = FLEXCAN_MAX_FIFO_MB;
+			else
+				i = flexcan->xmit_maxmb + 1;
+		}
+		if (i == flexcan->xmit_mb)
+			return -1;
+	} while (1);
+
+	flexcan->xmit_mb = i + 1;
+	if (flexcan->xmit_mb > flexcan->maxmb) {
+		if (flexcan->fifo)
+			flexcan->xmit_mb = FLEXCAN_MAX_FIFO_MB;
+		else
+			flexcan->xmit_mb = flexcan->xmit_maxmb + 1;
+	}
+
+	if (frame->can_id & CAN_RTR_FLAG)
+		hwmb[i].mb_cs |= 1 << MB_CS_RTR_OFFSET;
+	else
+		hwmb[i].mb_cs &= ~MB_CS_RTR_MASK;
+
+	if (frame->can_id & CAN_EFF_FLAG) {
+		hwmb[i].mb_cs |= 1 << MB_CS_IDE_OFFSET;
+		hwmb[i].mb_cs |= 1 << MB_CS_SRR_OFFSET;
+		hwmb[i].mb_id = frame->can_id & CAN_EFF_MASK;
+	} else {
+		hwmb[i].mb_cs &= ~MB_CS_IDE_MASK;
+		hwmb[i].mb_id = (frame->can_id & CAN_SFF_MASK) << 18;
+	}
+
+	hwmb[i].mb_cs &= ~MB_CS_LENGTH_MASK;
+	hwmb[i].mb_cs |= frame->can_dlc << MB_CS_LENGTH_OFFSET;
+	flexcan_memcpy(hwmb[i].mb_data, frame->data, frame->can_dlc);
+	hwmb[i].mb_cs &= ~MB_CS_CODE_MASK;
+	hwmb[i].mb_cs |= CAN_MB_TX_ONCE << MB_CS_CODE_OFFSET;
+	return 0;
+}
+
+/*!
+ * @brief function to initial message buffer
+ *
+ * @param flexcan	the pointer of can hardware device.
+ *
+ * @return	none
+ */
+void flexcan_mbm_init(struct flexcan_device *flexcan)
+{
+	struct can_hw_mb *hwmb;
+	int rx_mb, i;
+
+	/* Set global mask to receive all messages */
+	__raw_writel(0, flexcan->io_base + CAN_HW_REG_RXGMASK);
+	__raw_writel(0, flexcan->io_base + CAN_HW_REG_RX14MASK);
+	__raw_writel(0, flexcan->io_base + CAN_HW_REG_RX15MASK);
+
+	memset(flexcan->hwmb, 0, sizeof(*hwmb) * FLEXCAN_MAX_MB);
+	/* Set individual mask to receive all messages */
+	memset(flexcan->rx_mask, 0, sizeof(unsigned int) * FLEXCAN_MAX_MB);
+
+	if (flexcan->fifo)
+		rx_mb = FLEXCAN_MAX_FIFO_MB;
+	else
+		rx_mb = flexcan->maxmb - flexcan->xmit_maxmb;
+
+	hwmb = flexcan->hwmb;
+	if (flexcan->fifo) {
+		unsigned long *id_table = flexcan->io_base + CAN_FIFO_BASE;
+		for (i = 0; i < rx_mb; i++)
+			id_table[i] = 0;
+	} else {
+		for (i = 0; i < rx_mb; i++) {
+			hwmb[i].mb_cs &= ~MB_CS_CODE_MASK;
+			hwmb[i].mb_cs |= CAN_MB_RX_EMPTY << MB_CS_CODE_OFFSET;
+			/*
+			 * IDE bit can not control by mask registers
+			 * So set message buffer to receive extend
+			 * or standard message.
+			 */
+			if (flexcan->ext_msg && flexcan->std_msg) {
+				hwmb[i].mb_cs &= ~MB_CS_IDE_MASK;
+				hwmb[i].mb_cs |= (i & 1) << MB_CS_IDE_OFFSET;
+			} else {
+				if (flexcan->ext_msg)
+					hwmb[i].mb_cs |= 1 << MB_CS_IDE_OFFSET;
+			}
+		}
+	}
+
+	for (; i <= flexcan->maxmb; i++) {
+		hwmb[i].mb_cs &= ~MB_CS_CODE_MASK;
+		hwmb[i].mb_cs |= CAN_MB_TX_INACTIVE << MB_CS_CODE_OFFSET;
+	}
+
+	flexcan->xmit_mb = rx_mb;
+}