https://github.com/torvalds/linux
Tip revision: e49d033bddf5b565044e2abe4241353959bc9120 authored by Linus Torvalds on 04 April 2021, 21:15:36 UTC
Linux 5.12-rc6
Linux 5.12-rc6
Tip revision: e49d033
qca_spi.c
/*
* 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_7k_common.h"
#include "qca_debug.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_WRITE_VERIFY_MIN 0
#define QCASPI_WRITE_VERIFY_MAX 3
static int wr_verify = QCASPI_WRITE_VERIFY_MIN;
module_param(wr_verify, int, 0);
MODULE_PARM_DESC(wr_verify, "SPI register write verify trails. Use 0-3.");
#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, wr_verify);
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, 0);
qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, intr_enable, wr_verify);
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;
struct spi_transfer transfer[2];
int ret;
memset(&transfer, 0, sizeof(transfer));
spi_message_init(&msg);
cmd = cpu_to_be16(QCA7K_SPI_WRITE | QCA7K_SPI_EXTERNAL);
transfer[0].tx_buf = &cmd;
transfer[0].len = QCASPI_CMD_LEN;
transfer[1].tx_buf = src;
transfer[1].len = len;
spi_message_add_tail(&transfer[0], &msg);
spi_message_add_tail(&transfer[1], &msg);
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;
struct spi_transfer transfer;
int ret;
memset(&transfer, 0, sizeof(transfer));
spi_message_init(&msg);
transfer.tx_buf = src;
transfer.len = len;
spi_message_add_tail(&transfer, &msg);
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;
__be16 cmd;
struct spi_transfer transfer[2];
int ret;
memset(&transfer, 0, sizeof(transfer));
spi_message_init(&msg);
cmd = cpu_to_be16(QCA7K_SPI_READ | QCA7K_SPI_EXTERNAL);
transfer[0].tx_buf = &cmd;
transfer[0].len = QCASPI_CMD_LEN;
transfer[1].rx_buf = dst;
transfer[1].len = len;
spi_message_add_tail(&transfer[0], &msg);
spi_message_add_tail(&transfer[1], &msg);
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;
struct spi_transfer transfer;
int ret;
memset(&transfer, 0, sizeof(transfer));
spi_message_init(&msg);
transfer.rx_buf = dst;
transfer.len = len;
spi_message_add_tail(&transfer, &msg);
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_cmd(struct qcaspi *qca, u16 cmd)
{
__be16 tx_data;
struct spi_message msg;
struct spi_transfer transfer;
int ret;
memset(&transfer, 0, sizeof(transfer));
spi_message_init(&msg);
tx_data = cpu_to_be16(cmd);
transfer.len = sizeof(cmd);
transfer.tx_buf = &tx_data;
spi_message_add_tail(&transfer, &msg);
ret = spi_sync(qca->spi_dev, &msg);
if (!ret)
ret = msg.status;
if (ret)
qcaspi_spi_error(qca);
return ret;
}
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, wr_verify);
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);
if (available > QCASPI_HW_BUF_LEN) {
/* This could only happen by interferences on the SPI line.
* So retry later ...
*/
qca->stats.buf_avail_err++;
return -1;
}
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_ip_align(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 > QCASPI_HW_BUF_LEN + QCASPI_HW_PKT_LEN) {
/* This could only happen by interferences on the SPI line.
* So retry later ...
*/
qca->stats.buf_avail_err++;
return -1;
} else 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, wr_verify);
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_ip_align(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_MAX_LEN < 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;
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, 0);
qca->sync = QCASPI_SYNC_RESET;
qca->stats.trig_reset++;
qca->reset_count = 0;
break;
case QCASPI_SYNC_RESET:
qca->reset_count++;
netdev_dbg(qca->net_dev, "sync: waiting for CPU on, count %u.\n",
qca->reset_count);
if (qca->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;
}
static 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_spi(&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;
}
/* SPI thread takes care of TX queue */
return 0;
}
static 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, wr_verify);
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_MIN_LEN)
pad_len = QCAFRM_MIN_LEN - 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) {
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_zero(skb, 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++;
}
netif_trans_update(dev);
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, unsigned int txqueue)
{
struct qcaspi *qca = netdev_priv(dev);
netdev_info(qca->net_dev, "Transmit timeout at %ld, latency %ld\n",
jiffies, jiffies - dev_trans_start(dev));
qca->net_dev->stats.tx_errors++;
/* Trigger tx queue flush and QCA7000 reset */
qca->sync = QCASPI_SYNC_UNKNOWN;
if (qca->spi_thread)
wake_up_process(qca->spi_thread);
}
static int
qcaspi_netdev_init(struct net_device *dev)
{
struct qcaspi *qca = netdev_priv(dev);
dev->mtu = QCAFRM_MAX_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_ip_align(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;
dev_kfree_skb(qca->rx_skb);
}
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_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->priv_flags &= ~IFF_TX_SKB_SHARING;
dev->tx_queue_len = 100;
/* MTU range: 46 - 1500 */
dev->min_mtu = QCAFRM_MIN_MTU;
dev->max_mtu = QCAFRM_MAX_MTU;
qca = netdev_priv(dev);
memset(qca, 0, sizeof(struct qcaspi));
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)
{
struct qcaspi *qca = NULL;
struct net_device *qcaspi_devs = NULL;
u8 legacy_mode = 0;
u16 signature;
const char *mac;
if (!spi->dev.of_node) {
dev_err(&spi->dev, "Missing device tree\n");
return -EINVAL;
}
legacy_mode = of_property_read_bool(spi->dev.of_node,
"qca,legacy-mode");
if (qcaspi_clkspeed == 0) {
if (spi->max_speed_hz)
qcaspi_clkspeed = spi->max_speed_hz;
else
qcaspi_clkspeed = QCASPI_CLK_SPEED;
}
if ((qcaspi_clkspeed < QCASPI_CLK_SPEED_MIN) ||
(qcaspi_clkspeed > QCASPI_CLK_SPEED_MAX)) {
dev_err(&spi->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_err(&spi->dev, "Invalid burst len: %d\n",
qcaspi_burst_len);
return -EINVAL;
}
if ((qcaspi_pluggable < QCASPI_PLUGGABLE_MIN) ||
(qcaspi_pluggable > QCASPI_PLUGGABLE_MAX)) {
dev_err(&spi->dev, "Invalid pluggable: %d\n",
qcaspi_pluggable);
return -EINVAL;
}
if (wr_verify < QCASPI_WRITE_VERIFY_MIN ||
wr_verify > QCASPI_WRITE_VERIFY_MAX) {
dev_err(&spi->dev, "Invalid write verify: %d\n",
wr_verify);
return -EINVAL;
}
dev_info(&spi->dev, "ver=%s, clkspeed=%d, burst_len=%d, pluggable=%d\n",
QCASPI_DRV_VERSION,
qcaspi_clkspeed,
qcaspi_burst_len,
qcaspi_pluggable);
spi->mode = SPI_MODE_3;
spi->max_speed_hz = qcaspi_clkspeed;
if (spi_setup(spi) < 0) {
dev_err(&spi->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);
SET_NETDEV_DEV(qcaspi_devs, &spi->dev);
qca = netdev_priv(qcaspi_devs);
if (!qca) {
free_netdev(qcaspi_devs);
dev_err(&spi->dev, "Fail to retrieve private structure\n");
return -ENOMEM;
}
qca->net_dev = qcaspi_devs;
qca->spi_dev = spi;
qca->legacy_mode = legacy_mode;
spi_set_drvdata(spi, qcaspi_devs);
mac = of_get_mac_address(spi->dev.of_node);
if (!IS_ERR(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->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->dev, "Invalid signature (0x%04X)\n",
signature);
free_netdev(qcaspi_devs);
return -EFAULT;
}
}
if (register_netdev(qcaspi_devs)) {
dev_err(&spi->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)
{
struct net_device *qcaspi_devs = spi_get_drvdata(spi);
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,
.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 QCA7000 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);