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Diffstat (limited to 'kernel/drivers/net/ethernet/qualcomm/qca_spi.c')
-rw-r--r--kernel/drivers/net/ethernet/qualcomm/qca_spi.c990
1 files changed, 990 insertions, 0 deletions
diff --git a/kernel/drivers/net/ethernet/qualcomm/qca_spi.c b/kernel/drivers/net/ethernet/qualcomm/qca_spi.c
new file mode 100644
index 000000000..6af028d5f
--- /dev/null
+++ b/kernel/drivers/net/ethernet/qualcomm/qca_spi.c
@@ -0,0 +1,990 @@
+/*
+ * Copyright (c) 2011, 2012, Qualcomm Atheros Communications Inc.
+ * Copyright (c) 2014, I2SE GmbH
+ *
+ * Permission to use, copy, modify, and/or distribute this software
+ * for any purpose with or without fee is hereby granted, provided
+ * that the above copyright notice and this permission notice appear
+ * in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
+ * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
+ * THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+ * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
+ * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/* This module implements the Qualcomm Atheros SPI protocol for
+ * kernel-based SPI device; it is essentially an Ethernet-to-SPI
+ * serial converter;
+ */
+
+#include <linux/errno.h>
+#include <linux/etherdevice.h>
+#include <linux/if_arp.h>
+#include <linux/if_ether.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/netdevice.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_net.h>
+#include <linux/sched.h>
+#include <linux/skbuff.h>
+#include <linux/spi/spi.h>
+#include <linux/types.h>
+
+#include "qca_7k.h"
+#include "qca_debug.h"
+#include "qca_framing.h"
+#include "qca_spi.h"
+
+#define MAX_DMA_BURST_LEN 5000
+
+/* Modules parameters */
+#define QCASPI_CLK_SPEED_MIN 1000000
+#define QCASPI_CLK_SPEED_MAX 16000000
+#define QCASPI_CLK_SPEED 8000000
+static int qcaspi_clkspeed;
+module_param(qcaspi_clkspeed, int, 0);
+MODULE_PARM_DESC(qcaspi_clkspeed, "SPI bus clock speed (Hz). Use 1000000-16000000.");
+
+#define QCASPI_BURST_LEN_MIN 1
+#define QCASPI_BURST_LEN_MAX MAX_DMA_BURST_LEN
+static int qcaspi_burst_len = MAX_DMA_BURST_LEN;
+module_param(qcaspi_burst_len, int, 0);
+MODULE_PARM_DESC(qcaspi_burst_len, "Number of data bytes per burst. Use 1-5000.");
+
+#define QCASPI_PLUGGABLE_MIN 0
+#define QCASPI_PLUGGABLE_MAX 1
+static int qcaspi_pluggable = QCASPI_PLUGGABLE_MIN;
+module_param(qcaspi_pluggable, int, 0);
+MODULE_PARM_DESC(qcaspi_pluggable, "Pluggable SPI connection (yes/no).");
+
+#define QCASPI_MTU QCAFRM_ETHMAXMTU
+#define QCASPI_TX_TIMEOUT (1 * HZ)
+#define QCASPI_QCA7K_REBOOT_TIME_MS 1000
+
+static void
+start_spi_intr_handling(struct qcaspi *qca, u16 *intr_cause)
+{
+ *intr_cause = 0;
+
+ qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, 0);
+ qcaspi_read_register(qca, SPI_REG_INTR_CAUSE, intr_cause);
+ netdev_dbg(qca->net_dev, "interrupts: 0x%04x\n", *intr_cause);
+}
+
+static void
+end_spi_intr_handling(struct qcaspi *qca, u16 intr_cause)
+{
+ u16 intr_enable = (SPI_INT_CPU_ON |
+ SPI_INT_PKT_AVLBL |
+ SPI_INT_RDBUF_ERR |
+ SPI_INT_WRBUF_ERR);
+
+ qcaspi_write_register(qca, SPI_REG_INTR_CAUSE, intr_cause);
+ qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, intr_enable);
+ netdev_dbg(qca->net_dev, "acking int: 0x%04x\n", intr_cause);
+}
+
+static u32
+qcaspi_write_burst(struct qcaspi *qca, u8 *src, u32 len)
+{
+ __be16 cmd;
+ struct spi_message *msg = &qca->spi_msg2;
+ struct spi_transfer *transfer = &qca->spi_xfer2[0];
+ int ret;
+
+ cmd = cpu_to_be16(QCA7K_SPI_WRITE | QCA7K_SPI_EXTERNAL);
+ transfer->tx_buf = &cmd;
+ transfer->rx_buf = NULL;
+ transfer->len = QCASPI_CMD_LEN;
+ transfer = &qca->spi_xfer2[1];
+ transfer->tx_buf = src;
+ transfer->rx_buf = NULL;
+ transfer->len = len;
+
+ ret = spi_sync(qca->spi_dev, msg);
+
+ if (ret || (msg->actual_length != QCASPI_CMD_LEN + len)) {
+ qcaspi_spi_error(qca);
+ return 0;
+ }
+
+ return len;
+}
+
+static u32
+qcaspi_write_legacy(struct qcaspi *qca, u8 *src, u32 len)
+{
+ struct spi_message *msg = &qca->spi_msg1;
+ struct spi_transfer *transfer = &qca->spi_xfer1;
+ int ret;
+
+ transfer->tx_buf = src;
+ transfer->rx_buf = NULL;
+ transfer->len = len;
+
+ ret = spi_sync(qca->spi_dev, msg);
+
+ if (ret || (msg->actual_length != len)) {
+ qcaspi_spi_error(qca);
+ return 0;
+ }
+
+ return len;
+}
+
+static u32
+qcaspi_read_burst(struct qcaspi *qca, u8 *dst, u32 len)
+{
+ struct spi_message *msg = &qca->spi_msg2;
+ __be16 cmd;
+ struct spi_transfer *transfer = &qca->spi_xfer2[0];
+ int ret;
+
+ cmd = cpu_to_be16(QCA7K_SPI_READ | QCA7K_SPI_EXTERNAL);
+ transfer->tx_buf = &cmd;
+ transfer->rx_buf = NULL;
+ transfer->len = QCASPI_CMD_LEN;
+ transfer = &qca->spi_xfer2[1];
+ transfer->tx_buf = NULL;
+ transfer->rx_buf = dst;
+ transfer->len = len;
+
+ ret = spi_sync(qca->spi_dev, msg);
+
+ if (ret || (msg->actual_length != QCASPI_CMD_LEN + len)) {
+ qcaspi_spi_error(qca);
+ return 0;
+ }
+
+ return len;
+}
+
+static u32
+qcaspi_read_legacy(struct qcaspi *qca, u8 *dst, u32 len)
+{
+ struct spi_message *msg = &qca->spi_msg1;
+ struct spi_transfer *transfer = &qca->spi_xfer1;
+ int ret;
+
+ transfer->tx_buf = NULL;
+ transfer->rx_buf = dst;
+ transfer->len = len;
+
+ ret = spi_sync(qca->spi_dev, msg);
+
+ if (ret || (msg->actual_length != len)) {
+ qcaspi_spi_error(qca);
+ return 0;
+ }
+
+ return len;
+}
+
+static int
+qcaspi_tx_frame(struct qcaspi *qca, struct sk_buff *skb)
+{
+ u32 count;
+ u32 written;
+ u32 offset;
+ u32 len;
+
+ len = skb->len;
+
+ qcaspi_write_register(qca, SPI_REG_BFR_SIZE, len);
+ if (qca->legacy_mode)
+ qcaspi_tx_cmd(qca, QCA7K_SPI_WRITE | QCA7K_SPI_EXTERNAL);
+
+ offset = 0;
+ while (len) {
+ count = len;
+ if (count > qca->burst_len)
+ count = qca->burst_len;
+
+ if (qca->legacy_mode) {
+ written = qcaspi_write_legacy(qca,
+ skb->data + offset,
+ count);
+ } else {
+ written = qcaspi_write_burst(qca,
+ skb->data + offset,
+ count);
+ }
+
+ if (written != count)
+ return -1;
+
+ offset += count;
+ len -= count;
+ }
+
+ return 0;
+}
+
+static int
+qcaspi_transmit(struct qcaspi *qca)
+{
+ struct net_device_stats *n_stats = &qca->net_dev->stats;
+ u16 available = 0;
+ u32 pkt_len;
+ u16 new_head;
+ u16 packets = 0;
+
+ if (qca->txr.skb[qca->txr.head] == NULL)
+ return 0;
+
+ qcaspi_read_register(qca, SPI_REG_WRBUF_SPC_AVA, &available);
+
+ while (qca->txr.skb[qca->txr.head]) {
+ pkt_len = qca->txr.skb[qca->txr.head]->len + QCASPI_HW_PKT_LEN;
+
+ if (available < pkt_len) {
+ if (packets == 0)
+ qca->stats.write_buf_miss++;
+ break;
+ }
+
+ if (qcaspi_tx_frame(qca, qca->txr.skb[qca->txr.head]) == -1) {
+ qca->stats.write_err++;
+ return -1;
+ }
+
+ packets++;
+ n_stats->tx_packets++;
+ n_stats->tx_bytes += qca->txr.skb[qca->txr.head]->len;
+ available -= pkt_len;
+
+ /* remove the skb from the queue */
+ /* XXX After inconsistent lock states netif_tx_lock()
+ * has been replaced by netif_tx_lock_bh() and so on.
+ */
+ netif_tx_lock_bh(qca->net_dev);
+ dev_kfree_skb(qca->txr.skb[qca->txr.head]);
+ qca->txr.skb[qca->txr.head] = NULL;
+ qca->txr.size -= pkt_len;
+ new_head = qca->txr.head + 1;
+ if (new_head >= qca->txr.count)
+ new_head = 0;
+ qca->txr.head = new_head;
+ if (netif_queue_stopped(qca->net_dev))
+ netif_wake_queue(qca->net_dev);
+ netif_tx_unlock_bh(qca->net_dev);
+ }
+
+ return 0;
+}
+
+static int
+qcaspi_receive(struct qcaspi *qca)
+{
+ struct net_device *net_dev = qca->net_dev;
+ struct net_device_stats *n_stats = &net_dev->stats;
+ u16 available = 0;
+ u32 bytes_read;
+ u8 *cp;
+
+ /* Allocate rx SKB if we don't have one available. */
+ if (!qca->rx_skb) {
+ qca->rx_skb = netdev_alloc_skb(net_dev,
+ net_dev->mtu + VLAN_ETH_HLEN);
+ if (!qca->rx_skb) {
+ netdev_dbg(net_dev, "out of RX resources\n");
+ qca->stats.out_of_mem++;
+ return -1;
+ }
+ }
+
+ /* Read the packet size. */
+ qcaspi_read_register(qca, SPI_REG_RDBUF_BYTE_AVA, &available);
+ netdev_dbg(net_dev, "qcaspi_receive: SPI_REG_RDBUF_BYTE_AVA: Value: %08x\n",
+ available);
+
+ if (available == 0) {
+ netdev_dbg(net_dev, "qcaspi_receive called without any data being available!\n");
+ return -1;
+ }
+
+ qcaspi_write_register(qca, SPI_REG_BFR_SIZE, available);
+
+ if (qca->legacy_mode)
+ qcaspi_tx_cmd(qca, QCA7K_SPI_READ | QCA7K_SPI_EXTERNAL);
+
+ while (available) {
+ u32 count = available;
+
+ if (count > qca->burst_len)
+ count = qca->burst_len;
+
+ if (qca->legacy_mode) {
+ bytes_read = qcaspi_read_legacy(qca, qca->rx_buffer,
+ count);
+ } else {
+ bytes_read = qcaspi_read_burst(qca, qca->rx_buffer,
+ count);
+ }
+
+ netdev_dbg(net_dev, "available: %d, byte read: %d\n",
+ available, bytes_read);
+
+ if (bytes_read) {
+ available -= bytes_read;
+ } else {
+ qca->stats.read_err++;
+ return -1;
+ }
+
+ cp = qca->rx_buffer;
+
+ while ((bytes_read--) && (qca->rx_skb)) {
+ s32 retcode;
+
+ retcode = qcafrm_fsm_decode(&qca->frm_handle,
+ qca->rx_skb->data,
+ skb_tailroom(qca->rx_skb),
+ *cp);
+ cp++;
+ switch (retcode) {
+ case QCAFRM_GATHER:
+ case QCAFRM_NOHEAD:
+ break;
+ case QCAFRM_NOTAIL:
+ netdev_dbg(net_dev, "no RX tail\n");
+ n_stats->rx_errors++;
+ n_stats->rx_dropped++;
+ break;
+ case QCAFRM_INVLEN:
+ netdev_dbg(net_dev, "invalid RX length\n");
+ n_stats->rx_errors++;
+ n_stats->rx_dropped++;
+ break;
+ default:
+ qca->rx_skb->dev = qca->net_dev;
+ n_stats->rx_packets++;
+ n_stats->rx_bytes += retcode;
+ skb_put(qca->rx_skb, retcode);
+ qca->rx_skb->protocol = eth_type_trans(
+ qca->rx_skb, qca->rx_skb->dev);
+ qca->rx_skb->ip_summed = CHECKSUM_UNNECESSARY;
+ netif_rx_ni(qca->rx_skb);
+ qca->rx_skb = netdev_alloc_skb(net_dev,
+ net_dev->mtu + VLAN_ETH_HLEN);
+ if (!qca->rx_skb) {
+ netdev_dbg(net_dev, "out of RX resources\n");
+ n_stats->rx_errors++;
+ qca->stats.out_of_mem++;
+ break;
+ }
+ }
+ }
+ }
+
+ return 0;
+}
+
+/* Check that tx ring stores only so much bytes
+ * that fit into the internal QCA buffer.
+ */
+
+static int
+qcaspi_tx_ring_has_space(struct tx_ring *txr)
+{
+ if (txr->skb[txr->tail])
+ return 0;
+
+ return (txr->size + QCAFRM_ETHMAXLEN < QCASPI_HW_BUF_LEN) ? 1 : 0;
+}
+
+/* Flush the tx ring. This function is only safe to
+ * call from the qcaspi_spi_thread.
+ */
+
+static void
+qcaspi_flush_tx_ring(struct qcaspi *qca)
+{
+ int i;
+
+ /* XXX After inconsistent lock states netif_tx_lock()
+ * has been replaced by netif_tx_lock_bh() and so on.
+ */
+ netif_tx_lock_bh(qca->net_dev);
+ for (i = 0; i < TX_RING_MAX_LEN; i++) {
+ if (qca->txr.skb[i]) {
+ dev_kfree_skb(qca->txr.skb[i]);
+ qca->txr.skb[i] = NULL;
+ qca->net_dev->stats.tx_dropped++;
+ }
+ }
+ qca->txr.tail = 0;
+ qca->txr.head = 0;
+ qca->txr.size = 0;
+ netif_tx_unlock_bh(qca->net_dev);
+}
+
+static void
+qcaspi_qca7k_sync(struct qcaspi *qca, int event)
+{
+ u16 signature = 0;
+ u16 spi_config;
+ u16 wrbuf_space = 0;
+ static u16 reset_count;
+
+ if (event == QCASPI_EVENT_CPUON) {
+ /* Read signature twice, if not valid
+ * go back to unknown state.
+ */
+ qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
+ qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
+ if (signature != QCASPI_GOOD_SIGNATURE) {
+ qca->sync = QCASPI_SYNC_UNKNOWN;
+ netdev_dbg(qca->net_dev, "sync: got CPU on, but signature was invalid, restart\n");
+ } else {
+ /* ensure that the WRBUF is empty */
+ qcaspi_read_register(qca, SPI_REG_WRBUF_SPC_AVA,
+ &wrbuf_space);
+ if (wrbuf_space != QCASPI_HW_BUF_LEN) {
+ netdev_dbg(qca->net_dev, "sync: got CPU on, but wrbuf not empty. reset!\n");
+ qca->sync = QCASPI_SYNC_UNKNOWN;
+ } else {
+ netdev_dbg(qca->net_dev, "sync: got CPU on, now in sync\n");
+ qca->sync = QCASPI_SYNC_READY;
+ return;
+ }
+ }
+ }
+
+ switch (qca->sync) {
+ case QCASPI_SYNC_READY:
+ /* Read signature, if not valid go to unknown state. */
+ qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
+ if (signature != QCASPI_GOOD_SIGNATURE) {
+ qca->sync = QCASPI_SYNC_UNKNOWN;
+ netdev_dbg(qca->net_dev, "sync: bad signature, restart\n");
+ /* don't reset right away */
+ return;
+ }
+ break;
+ case QCASPI_SYNC_UNKNOWN:
+ /* Read signature, if not valid stay in unknown state */
+ qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
+ if (signature != QCASPI_GOOD_SIGNATURE) {
+ netdev_dbg(qca->net_dev, "sync: could not read signature to reset device, retry.\n");
+ return;
+ }
+
+ /* TODO: use GPIO to reset QCA7000 in legacy mode*/
+ netdev_dbg(qca->net_dev, "sync: resetting device.\n");
+ qcaspi_read_register(qca, SPI_REG_SPI_CONFIG, &spi_config);
+ spi_config |= QCASPI_SLAVE_RESET_BIT;
+ qcaspi_write_register(qca, SPI_REG_SPI_CONFIG, spi_config);
+
+ qca->sync = QCASPI_SYNC_RESET;
+ qca->stats.trig_reset++;
+ reset_count = 0;
+ break;
+ case QCASPI_SYNC_RESET:
+ reset_count++;
+ netdev_dbg(qca->net_dev, "sync: waiting for CPU on, count %u.\n",
+ reset_count);
+ if (reset_count >= QCASPI_RESET_TIMEOUT) {
+ /* reset did not seem to take place, try again */
+ qca->sync = QCASPI_SYNC_UNKNOWN;
+ qca->stats.reset_timeout++;
+ netdev_dbg(qca->net_dev, "sync: reset timeout, restarting process.\n");
+ }
+ break;
+ }
+}
+
+static int
+qcaspi_spi_thread(void *data)
+{
+ struct qcaspi *qca = data;
+ u16 intr_cause = 0;
+
+ netdev_info(qca->net_dev, "SPI thread created\n");
+ while (!kthread_should_stop()) {
+ set_current_state(TASK_INTERRUPTIBLE);
+ if ((qca->intr_req == qca->intr_svc) &&
+ (qca->txr.skb[qca->txr.head] == NULL) &&
+ (qca->sync == QCASPI_SYNC_READY))
+ schedule();
+
+ set_current_state(TASK_RUNNING);
+
+ netdev_dbg(qca->net_dev, "have work to do. int: %d, tx_skb: %p\n",
+ qca->intr_req - qca->intr_svc,
+ qca->txr.skb[qca->txr.head]);
+
+ qcaspi_qca7k_sync(qca, QCASPI_EVENT_UPDATE);
+
+ if (qca->sync != QCASPI_SYNC_READY) {
+ netdev_dbg(qca->net_dev, "sync: not ready %u, turn off carrier and flush\n",
+ (unsigned int)qca->sync);
+ netif_stop_queue(qca->net_dev);
+ netif_carrier_off(qca->net_dev);
+ qcaspi_flush_tx_ring(qca);
+ msleep(QCASPI_QCA7K_REBOOT_TIME_MS);
+ }
+
+ if (qca->intr_svc != qca->intr_req) {
+ qca->intr_svc = qca->intr_req;
+ start_spi_intr_handling(qca, &intr_cause);
+
+ if (intr_cause & SPI_INT_CPU_ON) {
+ qcaspi_qca7k_sync(qca, QCASPI_EVENT_CPUON);
+
+ /* not synced. */
+ if (qca->sync != QCASPI_SYNC_READY)
+ continue;
+
+ qca->stats.device_reset++;
+ netif_wake_queue(qca->net_dev);
+ netif_carrier_on(qca->net_dev);
+ }
+
+ if (intr_cause & SPI_INT_RDBUF_ERR) {
+ /* restart sync */
+ netdev_dbg(qca->net_dev, "===> rdbuf error!\n");
+ qca->stats.read_buf_err++;
+ qca->sync = QCASPI_SYNC_UNKNOWN;
+ continue;
+ }
+
+ if (intr_cause & SPI_INT_WRBUF_ERR) {
+ /* restart sync */
+ netdev_dbg(qca->net_dev, "===> wrbuf error!\n");
+ qca->stats.write_buf_err++;
+ qca->sync = QCASPI_SYNC_UNKNOWN;
+ continue;
+ }
+
+ /* can only handle other interrupts
+ * if sync has occurred
+ */
+ if (qca->sync == QCASPI_SYNC_READY) {
+ if (intr_cause & SPI_INT_PKT_AVLBL)
+ qcaspi_receive(qca);
+ }
+
+ end_spi_intr_handling(qca, intr_cause);
+ }
+
+ if (qca->sync == QCASPI_SYNC_READY)
+ qcaspi_transmit(qca);
+ }
+ set_current_state(TASK_RUNNING);
+ netdev_info(qca->net_dev, "SPI thread exit\n");
+
+ return 0;
+}
+
+static irqreturn_t
+qcaspi_intr_handler(int irq, void *data)
+{
+ struct qcaspi *qca = data;
+
+ qca->intr_req++;
+ if (qca->spi_thread &&
+ qca->spi_thread->state != TASK_RUNNING)
+ wake_up_process(qca->spi_thread);
+
+ return IRQ_HANDLED;
+}
+
+int
+qcaspi_netdev_open(struct net_device *dev)
+{
+ struct qcaspi *qca = netdev_priv(dev);
+ int ret = 0;
+
+ if (!qca)
+ return -EINVAL;
+
+ qca->intr_req = 1;
+ qca->intr_svc = 0;
+ qca->sync = QCASPI_SYNC_UNKNOWN;
+ qcafrm_fsm_init(&qca->frm_handle);
+
+ qca->spi_thread = kthread_run((void *)qcaspi_spi_thread,
+ qca, "%s", dev->name);
+
+ if (IS_ERR(qca->spi_thread)) {
+ netdev_err(dev, "%s: unable to start kernel thread.\n",
+ QCASPI_DRV_NAME);
+ return PTR_ERR(qca->spi_thread);
+ }
+
+ ret = request_irq(qca->spi_dev->irq, qcaspi_intr_handler, 0,
+ dev->name, qca);
+ if (ret) {
+ netdev_err(dev, "%s: unable to get IRQ %d (irqval=%d).\n",
+ QCASPI_DRV_NAME, qca->spi_dev->irq, ret);
+ kthread_stop(qca->spi_thread);
+ return ret;
+ }
+
+ netif_start_queue(qca->net_dev);
+
+ return 0;
+}
+
+int
+qcaspi_netdev_close(struct net_device *dev)
+{
+ struct qcaspi *qca = netdev_priv(dev);
+
+ netif_stop_queue(dev);
+
+ qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, 0);
+ free_irq(qca->spi_dev->irq, qca);
+
+ kthread_stop(qca->spi_thread);
+ qca->spi_thread = NULL;
+ qcaspi_flush_tx_ring(qca);
+
+ return 0;
+}
+
+static netdev_tx_t
+qcaspi_netdev_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ u32 frame_len;
+ u8 *ptmp;
+ struct qcaspi *qca = netdev_priv(dev);
+ u16 new_tail;
+ struct sk_buff *tskb;
+ u8 pad_len = 0;
+
+ if (skb->len < QCAFRM_ETHMINLEN)
+ pad_len = QCAFRM_ETHMINLEN - skb->len;
+
+ if (qca->txr.skb[qca->txr.tail]) {
+ netdev_warn(qca->net_dev, "queue was unexpectedly full!\n");
+ netif_stop_queue(qca->net_dev);
+ qca->stats.ring_full++;
+ return NETDEV_TX_BUSY;
+ }
+
+ if ((skb_headroom(skb) < QCAFRM_HEADER_LEN) ||
+ (skb_tailroom(skb) < QCAFRM_FOOTER_LEN + pad_len)) {
+ tskb = skb_copy_expand(skb, QCAFRM_HEADER_LEN,
+ QCAFRM_FOOTER_LEN + pad_len, GFP_ATOMIC);
+ if (!tskb) {
+ netdev_dbg(qca->net_dev, "could not allocate tx_buff\n");
+ qca->stats.out_of_mem++;
+ return NETDEV_TX_BUSY;
+ }
+ dev_kfree_skb(skb);
+ skb = tskb;
+ }
+
+ frame_len = skb->len + pad_len;
+
+ ptmp = skb_push(skb, QCAFRM_HEADER_LEN);
+ qcafrm_create_header(ptmp, frame_len);
+
+ if (pad_len) {
+ ptmp = skb_put(skb, pad_len);
+ memset(ptmp, 0, pad_len);
+ }
+
+ ptmp = skb_put(skb, QCAFRM_FOOTER_LEN);
+ qcafrm_create_footer(ptmp);
+
+ netdev_dbg(qca->net_dev, "Tx-ing packet: Size: 0x%08x\n",
+ skb->len);
+
+ qca->txr.size += skb->len + QCASPI_HW_PKT_LEN;
+
+ new_tail = qca->txr.tail + 1;
+ if (new_tail >= qca->txr.count)
+ new_tail = 0;
+
+ qca->txr.skb[qca->txr.tail] = skb;
+ qca->txr.tail = new_tail;
+
+ if (!qcaspi_tx_ring_has_space(&qca->txr)) {
+ netif_stop_queue(qca->net_dev);
+ qca->stats.ring_full++;
+ }
+
+ dev->trans_start = jiffies;
+
+ if (qca->spi_thread &&
+ qca->spi_thread->state != TASK_RUNNING)
+ wake_up_process(qca->spi_thread);
+
+ return NETDEV_TX_OK;
+}
+
+static void
+qcaspi_netdev_tx_timeout(struct net_device *dev)
+{
+ struct qcaspi *qca = netdev_priv(dev);
+
+ netdev_info(qca->net_dev, "Transmit timeout at %ld, latency %ld\n",
+ jiffies, jiffies - dev->trans_start);
+ qca->net_dev->stats.tx_errors++;
+ /* wake the queue if there is room */
+ if (qcaspi_tx_ring_has_space(&qca->txr))
+ netif_wake_queue(dev);
+}
+
+static int
+qcaspi_netdev_init(struct net_device *dev)
+{
+ struct qcaspi *qca = netdev_priv(dev);
+
+ dev->mtu = QCASPI_MTU;
+ dev->type = ARPHRD_ETHER;
+ qca->clkspeed = qcaspi_clkspeed;
+ qca->burst_len = qcaspi_burst_len;
+ qca->spi_thread = NULL;
+ qca->buffer_size = (dev->mtu + VLAN_ETH_HLEN + QCAFRM_HEADER_LEN +
+ QCAFRM_FOOTER_LEN + 4) * 4;
+
+ memset(&qca->stats, 0, sizeof(struct qcaspi_stats));
+
+ qca->rx_buffer = kmalloc(qca->buffer_size, GFP_KERNEL);
+ if (!qca->rx_buffer)
+ return -ENOBUFS;
+
+ qca->rx_skb = netdev_alloc_skb(dev, qca->net_dev->mtu + VLAN_ETH_HLEN);
+ if (!qca->rx_skb) {
+ kfree(qca->rx_buffer);
+ netdev_info(qca->net_dev, "Failed to allocate RX sk_buff.\n");
+ return -ENOBUFS;
+ }
+
+ return 0;
+}
+
+static void
+qcaspi_netdev_uninit(struct net_device *dev)
+{
+ struct qcaspi *qca = netdev_priv(dev);
+
+ kfree(qca->rx_buffer);
+ qca->buffer_size = 0;
+ if (qca->rx_skb)
+ dev_kfree_skb(qca->rx_skb);
+}
+
+static int
+qcaspi_netdev_change_mtu(struct net_device *dev, int new_mtu)
+{
+ if ((new_mtu < QCAFRM_ETHMINMTU) || (new_mtu > QCAFRM_ETHMAXMTU))
+ return -EINVAL;
+
+ dev->mtu = new_mtu;
+
+ return 0;
+}
+
+static const struct net_device_ops qcaspi_netdev_ops = {
+ .ndo_init = qcaspi_netdev_init,
+ .ndo_uninit = qcaspi_netdev_uninit,
+ .ndo_open = qcaspi_netdev_open,
+ .ndo_stop = qcaspi_netdev_close,
+ .ndo_start_xmit = qcaspi_netdev_xmit,
+ .ndo_change_mtu = qcaspi_netdev_change_mtu,
+ .ndo_set_mac_address = eth_mac_addr,
+ .ndo_tx_timeout = qcaspi_netdev_tx_timeout,
+ .ndo_validate_addr = eth_validate_addr,
+};
+
+static void
+qcaspi_netdev_setup(struct net_device *dev)
+{
+ struct qcaspi *qca = NULL;
+
+ dev->netdev_ops = &qcaspi_netdev_ops;
+ qcaspi_set_ethtool_ops(dev);
+ dev->watchdog_timeo = QCASPI_TX_TIMEOUT;
+ dev->flags = IFF_MULTICAST;
+ dev->tx_queue_len = 100;
+
+ qca = netdev_priv(dev);
+ memset(qca, 0, sizeof(struct qcaspi));
+
+ memset(&qca->spi_xfer1, 0, sizeof(struct spi_transfer));
+ memset(&qca->spi_xfer2, 0, sizeof(struct spi_transfer) * 2);
+
+ spi_message_init(&qca->spi_msg1);
+ spi_message_add_tail(&qca->spi_xfer1, &qca->spi_msg1);
+
+ spi_message_init(&qca->spi_msg2);
+ spi_message_add_tail(&qca->spi_xfer2[0], &qca->spi_msg2);
+ spi_message_add_tail(&qca->spi_xfer2[1], &qca->spi_msg2);
+
+ memset(&qca->txr, 0, sizeof(qca->txr));
+ qca->txr.count = TX_RING_MAX_LEN;
+}
+
+static const struct of_device_id qca_spi_of_match[] = {
+ { .compatible = "qca,qca7000" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, qca_spi_of_match);
+
+static int
+qca_spi_probe(struct spi_device *spi_device)
+{
+ struct qcaspi *qca = NULL;
+ struct net_device *qcaspi_devs = NULL;
+ u8 legacy_mode = 0;
+ u16 signature;
+ const char *mac;
+
+ if (!spi_device->dev.of_node) {
+ dev_err(&spi_device->dev, "Missing device tree\n");
+ return -EINVAL;
+ }
+
+ legacy_mode = of_property_read_bool(spi_device->dev.of_node,
+ "qca,legacy-mode");
+
+ if (qcaspi_clkspeed == 0) {
+ if (spi_device->max_speed_hz)
+ qcaspi_clkspeed = spi_device->max_speed_hz;
+ else
+ qcaspi_clkspeed = QCASPI_CLK_SPEED;
+ }
+
+ if ((qcaspi_clkspeed < QCASPI_CLK_SPEED_MIN) ||
+ (qcaspi_clkspeed > QCASPI_CLK_SPEED_MAX)) {
+ dev_info(&spi_device->dev, "Invalid clkspeed: %d\n",
+ qcaspi_clkspeed);
+ return -EINVAL;
+ }
+
+ if ((qcaspi_burst_len < QCASPI_BURST_LEN_MIN) ||
+ (qcaspi_burst_len > QCASPI_BURST_LEN_MAX)) {
+ dev_info(&spi_device->dev, "Invalid burst len: %d\n",
+ qcaspi_burst_len);
+ return -EINVAL;
+ }
+
+ if ((qcaspi_pluggable < QCASPI_PLUGGABLE_MIN) ||
+ (qcaspi_pluggable > QCASPI_PLUGGABLE_MAX)) {
+ dev_info(&spi_device->dev, "Invalid pluggable: %d\n",
+ qcaspi_pluggable);
+ return -EINVAL;
+ }
+
+ dev_info(&spi_device->dev, "ver=%s, clkspeed=%d, burst_len=%d, pluggable=%d\n",
+ QCASPI_DRV_VERSION,
+ qcaspi_clkspeed,
+ qcaspi_burst_len,
+ qcaspi_pluggable);
+
+ spi_device->mode = SPI_MODE_3;
+ spi_device->max_speed_hz = qcaspi_clkspeed;
+ if (spi_setup(spi_device) < 0) {
+ dev_err(&spi_device->dev, "Unable to setup SPI device\n");
+ return -EFAULT;
+ }
+
+ qcaspi_devs = alloc_etherdev(sizeof(struct qcaspi));
+ if (!qcaspi_devs)
+ return -ENOMEM;
+
+ qcaspi_netdev_setup(qcaspi_devs);
+
+ qca = netdev_priv(qcaspi_devs);
+ if (!qca) {
+ free_netdev(qcaspi_devs);
+ dev_err(&spi_device->dev, "Fail to retrieve private structure\n");
+ return -ENOMEM;
+ }
+ qca->net_dev = qcaspi_devs;
+ qca->spi_dev = spi_device;
+ qca->legacy_mode = legacy_mode;
+
+ spi_set_drvdata(spi_device, qcaspi_devs);
+
+ mac = of_get_mac_address(spi_device->dev.of_node);
+
+ if (mac)
+ ether_addr_copy(qca->net_dev->dev_addr, mac);
+
+ if (!is_valid_ether_addr(qca->net_dev->dev_addr)) {
+ eth_hw_addr_random(qca->net_dev);
+ dev_info(&spi_device->dev, "Using random MAC address: %pM\n",
+ qca->net_dev->dev_addr);
+ }
+
+ netif_carrier_off(qca->net_dev);
+
+ if (!qcaspi_pluggable) {
+ qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
+ qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
+
+ if (signature != QCASPI_GOOD_SIGNATURE) {
+ dev_err(&spi_device->dev, "Invalid signature (0x%04X)\n",
+ signature);
+ free_netdev(qcaspi_devs);
+ return -EFAULT;
+ }
+ }
+
+ if (register_netdev(qcaspi_devs)) {
+ dev_info(&spi_device->dev, "Unable to register net device %s\n",
+ qcaspi_devs->name);
+ free_netdev(qcaspi_devs);
+ return -EFAULT;
+ }
+
+ qcaspi_init_device_debugfs(qca);
+
+ return 0;
+}
+
+static int
+qca_spi_remove(struct spi_device *spi_device)
+{
+ struct net_device *qcaspi_devs = spi_get_drvdata(spi_device);
+ struct qcaspi *qca = netdev_priv(qcaspi_devs);
+
+ qcaspi_remove_device_debugfs(qca);
+
+ unregister_netdev(qcaspi_devs);
+ free_netdev(qcaspi_devs);
+
+ return 0;
+}
+
+static const struct spi_device_id qca_spi_id[] = {
+ { "qca7000", 0 },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(spi, qca_spi_id);
+
+static struct spi_driver qca_spi_driver = {
+ .driver = {
+ .name = QCASPI_DRV_NAME,
+ .owner = THIS_MODULE,
+ .of_match_table = qca_spi_of_match,
+ },
+ .id_table = qca_spi_id,
+ .probe = qca_spi_probe,
+ .remove = qca_spi_remove,
+};
+module_spi_driver(qca_spi_driver);
+
+MODULE_DESCRIPTION("Qualcomm Atheros SPI Driver");
+MODULE_AUTHOR("Qualcomm Atheros Communications");
+MODULE_AUTHOR("Stefan Wahren <stefan.wahren@i2se.com>");
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_VERSION(QCASPI_DRV_VERSION);