/*
Broadcom B43 wireless driver
PIO Transmission
Copyright (c) 2005 Michael Buesch <mb@bu3sch.de>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; see the file COPYING. If not, write to
the Free Software Foundation, Inc., 51 Franklin Steet, Fifth Floor,
Boston, MA 02110-1301, USA.
*/
#include "b43.h"
#include "pio.h"
#include "main.h"
#include "xmit.h"
#include <linux/delay.h>
static void tx_start(struct b43_pioqueue *queue)
{
b43_pio_write(queue, B43_PIO_TXCTL, B43_PIO_TXCTL_INIT);
}
static void tx_octet(struct b43_pioqueue *queue, u8 octet)
{
if (queue->need_workarounds) {
b43_pio_write(queue, B43_PIO_TXDATA, octet);
b43_pio_write(queue, B43_PIO_TXCTL, B43_PIO_TXCTL_WRITELO);
} else {
b43_pio_write(queue, B43_PIO_TXCTL, B43_PIO_TXCTL_WRITELO);
b43_pio_write(queue, B43_PIO_TXDATA, octet);
}
}
static u16 tx_get_next_word(const u8 * txhdr,
const u8 * packet,
size_t txhdr_size, unsigned int *pos)
{
const u8 *source;
unsigned int i = *pos;
u16 ret;
if (i < txhdr_size) {
source = txhdr;
} else {
source = packet;
i -= txhdr_size;
}
ret = le16_to_cpu(*((__le16 *)(source + i)));
*pos += 2;
return ret;
}
static void tx_data(struct b43_pioqueue *queue,
u8 * txhdr, const u8 * packet, unsigned int octets)
{
u16 data;
unsigned int i = 0;
if (queue->need_workarounds) {
data = tx_get_next_word(txhdr, packet,
sizeof(struct b43_txhdr_fw4), &i);
b43_pio_write(queue, B43_PIO_TXDATA, data);
}
b43_pio_write(queue, B43_PIO_TXCTL,
B43_PIO_TXCTL_WRITELO | B43_PIO_TXCTL_WRITEHI);
while (i < octets - 1) {
data = tx_get_next_word(txhdr, packet,
sizeof(struct b43_txhdr_fw4), &i);
b43_pio_write(queue, B43_PIO_TXDATA, data);
}
if (octets % 2)
tx_octet(queue,
packet[octets - sizeof(struct b43_txhdr_fw4) - 1]);
}
static void tx_complete(struct b43_pioqueue *queue, struct sk_buff *skb)
{
if (queue->need_workarounds) {
b43_pio_write(queue, B43_PIO_TXDATA, skb->data[skb->len - 1]);
b43_pio_write(queue, B43_PIO_TXCTL,
B43_PIO_TXCTL_WRITELO | B43_PIO_TXCTL_COMPLETE);
} else {
b43_pio_write(queue, B43_PIO_TXCTL, B43_PIO_TXCTL_COMPLETE);
}
}
static u16 generate_cookie(struct b43_pioqueue *queue,
struct b43_pio_txpacket *packet)
{
u16 cookie = 0x0000;
u16 packetindex;
/* We use the upper 4 bits for the PIO
* controller ID and the lower 12 bits
* for the packet index (in the cache).
*/
switch (queue->mmio_base) {
case B43_MMIO_PIO1_BASE:
break;
case B43_MMIO_PIO2_BASE:
cookie = 0x1000;
break;
case B43_MMIO_PIO3_BASE:
cookie = 0x2000;
break;
case B43_MMIO_PIO4_BASE:
cookie = 0x3000;
break;
default:
B43_WARN_ON(1);
}
packetindex = packet->index;
B43_WARN_ON(packetindex & ~0x0FFF);
cookie |= (u16) packetindex;
return cookie;
}
static
struct b43_pioqueue *parse_cookie(struct b43_wldev *dev,
u16 cookie, struct b43_pio_txpacket **packet)
{
struct b43_pio *pio = &dev->pio;
struct b43_pioqueue *queue = NULL;
int packetindex;
switch (cookie & 0xF000) {
case 0x0000:
queue = pio->queue0;
break;
case 0x1000:
queue = pio->queue1;
break;
case 0x2000:
queue = pio->queue2;
break;
case 0x3000:
queue = pio->queue3;
break;
default:
B43_WARN_ON(1);
}
packetindex = (cookie & 0x0FFF);
B43_WARN_ON(!(packetindex >= 0 && packetindex < B43_PIO_MAXTXPACKETS));
*packet = &(queue->tx_packets_cache[packetindex]);
return queue;
}
union txhdr_union {
struct b43_txhdr_fw4 txhdr_fw4;
};
static void pio_tx_write_fragment(struct b43_pioqueue *queue,
struct sk_buff *skb,
struct b43_pio_txpacket *packet,
size_t txhdr_size)
{
union txhdr_union txhdr_data;
u8 *txhdr = NULL;
unsigned int octets;
txhdr = (u8 *) (&txhdr_data.txhdr_fw4);
B43_WARN_ON(skb_shinfo(skb)->nr_frags);
b43_generate_txhdr(queue->dev,
txhdr, skb->data, skb->len,
&packet->txstat.control,
generate_cookie(queue, packet));
tx_start(queue);
octets = skb->len + txhdr_size;
if (queue->need_workarounds)
octets--;
tx_data(queue, txhdr, (u8 *) skb->data, octets);
tx_complete(queue, skb);
}
static void free_txpacket(struct b43_pio_txpacket *packet)
{
struct b43_pioqueue *queue = packet->queue;
if (packet->skb)
dev_kfree_skb_any(packet->skb);
list_move(&packet->list, &queue->txfree);
queue->nr_txfree++;
}
static int pio_tx_packet(struct b43_pio_txpacket *packet)
{
struct b43_pioqueue *queue = packet->queue;
struct sk_buff *skb = packet->skb;
u16 octets;
octets = (u16) skb->len + sizeof(struct b43_txhdr_fw4);
if (queue->tx_devq_size < octets) {
b43warn(queue->dev->wl, "PIO queue too small. "
"Dropping packet.\n");
/* Drop it silently (return success) */
free_txpacket(packet);
return 0;
}
B43_WARN_ON(queue->tx_devq_packets > B43_PIO_MAXTXDEVQPACKETS);
B43_WARN_ON(queue->tx_devq_used > queue->tx_devq_size);
/* Check if there is sufficient free space on the device
* TX queue. If not, return and let the TX tasklet
* retry later.
*/
if (queue->tx_devq_packets == B43_PIO_MAXTXDEVQPACKETS)
return -EBUSY;
if (queue->tx_devq_used + octets > queue->tx_devq_size)
return -EBUSY;
/* Now poke the device. */
pio_tx_write_fragment(queue, skb, packet, sizeof(struct b43_txhdr_fw4));
/* Account for the packet size.
* (We must not overflow the device TX queue)
*/
queue->tx_devq_packets++;
queue->tx_devq_used += octets;
/* Transmission started, everything ok, move the
* packet to the txrunning list.
*/
list_move_tail(&packet->list, &queue->txrunning);
return 0;
}
static void tx_tasklet(unsigned long d)
{
struct b43_pioqueue *queue = (struct b43_pioqueue *)d;
struct b43_wldev *dev = queue->dev;
unsigned long flags;
struct b43_pio_txpacket *packet, *tmp_packet;
int err;
u16 txctl;
spin_lock_irqsave(&dev->wl->irq_lock, flags);
if (queue->tx_frozen)
goto out_unlock;
txctl = b43_pio_read(queue, B43_PIO_TXCTL);
if (txctl & B43_PIO_TXCTL_SUSPEND)
goto out_unlock;
list_for_each_entry_safe(packet, tmp_packet, &queue->txqueue, list) {
/* Try to transmit the packet. This can fail, if
* the device queue is full. In case of failure, the
* packet is left in the txqueue.
* If transmission succeed, the packet is moved to txrunning.
* If it is impossible to transmit the packet, it
* is dropped.
*/
err = pio_tx_packet(packet);
if (err)
break;
}
out_unlock:
spin_unlock_irqrestore(&dev->wl->irq_lock, flags);
}
static void setup_txqueues(struct b43_pioqueue *queue)
{
struct b43_pio_txpacket *packet;
int i;
queue->nr_txfree = B43_PIO_MAXTXPACKETS;
for (i = 0; i < B43_PIO_MAXTXPACKETS; i++) {
packet = &(queue->tx_packets_cache[i]);
packet->queue = queue;
INIT_LIST_HEAD(&packet->list);
packet->index = i;
list_add(&packet->list, &queue->txfree);
}
}
static
struct b43_pioqueue *b43_setup_pioqueue(struct b43_wldev *dev,
u16 pio_mmio_base)
{
struct b43_pioqueue *queue;
u16 qsize;
queue = kzalloc(sizeof(*queue), GFP_KERNEL);
if (!queue)
goto out;
queue->dev = dev;
queue->mmio_base = pio_mmio_base;
queue->need_workarounds = (dev->dev->id.revision < 3);
INIT_LIST_HEAD(&queue->txfree);
INIT_LIST_HEAD(&queue->txqueue);
INIT_LIST_HEAD(&queue->txrunning);
tasklet_init(&queue->txtask, tx_tasklet, (unsigned long)queue);
b43_write32(dev, B43_MMIO_MACCTL, b43_read32(dev, B43_MMIO_MACCTL)
& ~B43_MACCTL_BE);
qsize = b43_read16(dev, queue->mmio_base + B43_PIO_TXQBUFSIZE);
if (qsize == 0) {
b43err(dev->wl, "This card does not support PIO "
"operation mode. Please use DMA mode "
"(module parameter pio=0).\n");
goto err_freequeue;
}
if (qsize <= B43_PIO_TXQADJUST) {
b43err(dev->wl, "PIO tx device-queue too small (%u)\n", qsize);
goto err_freequeue;
}
qsize -= B43_PIO_TXQADJUST;
queue->tx_devq_size = qsize;
setup_txqueues(queue);
out:
return queue;
err_freequeue:
kfree(queue);
queue = NULL;
goto out;
}
static void cancel_transfers(struct b43_pioqueue *queue)
{
struct b43_pio_txpacket *packet, *tmp_packet;
tasklet_disable(&queue->txtask);
list_for_each_entry_safe(packet, tmp_packet, &queue->txrunning, list)
free_txpacket(packet);
list_for_each_entry_safe(packet, tmp_packet, &queue->txqueue, list)
free_txpacket(packet);
}
static void b43_destroy_pioqueue(struct b43_pioqueue *queue)
{
if (!queue)
return;
cancel_transfers(queue);
kfree(queue);
}
void b43_pio_free(struct b43_wldev *dev)
{
struct b43_pio *pio;
if (!b43_using_pio(dev))
return;
pio = &dev->pio;
b43_destroy_pioqueue(pio->queue3);
pio->queue3 = NULL;
b43_destroy_pioqueue(pio->queue2);
pio->queue2 = NULL;
b43_destroy_pioqueue(pio->queue1);
pio->queue1 = NULL;
b43_destroy_pioqueue(pio->queue0);
pio->queue0 = NULL;
}
int b43_pio_init(struct b43_wldev *dev)
{
struct b43_pio *pio = &dev->pio;
struct b43_pioqueue *queue;
int err = -ENOMEM;
queue = b43_setup_pioqueue(dev, B43_MMIO_PIO1_BASE);
if (!queue)
goto out;
pio->queue0 = queue;
queue = b43_setup_pioqueue(dev, B43_MMIO_PIO2_BASE);
if (!queue)
goto err_destroy0;
pio->queue1 = queue;
queue = b43_setup_pioqueue(dev, B43_MMIO_PIO3_BASE);
if (!queue)
goto err_destroy1;
pio->queue2 = queue;
queue = b43_setup_pioqueue(dev, B43_MMIO_PIO4_BASE);
if (!queue)
goto err_destroy2;
pio->queue3 = queue;
if (dev->dev->id.revision < 3)
dev->irq_savedstate |= B43_IRQ_PIO_WORKAROUND;
b43dbg(dev->wl, "PIO initialized\n");
err = 0;
out:
return err;
err_destroy2:
b43_destroy_pioqueue(pio->queue2);
pio->queue2 = NULL;
err_destroy1:
b43_destroy_pioqueue(pio->queue1);
pio->queue1 = NULL;
err_destroy0:
b43_destroy_pioqueue(pio->queue0);
pio->queue0 = NULL;
goto out;
}
int b43_pio_tx(struct b43_wldev *dev,
struct sk_buff *skb, struct ieee80211_tx_control *ctl)
{
struct b43_pioqueue *queue = dev->pio.queue1;
struct b43_pio_txpacket *packet;
B43_WARN_ON(queue->tx_suspended);
B43_WARN_ON(list_empty(&queue->txfree));
packet = list_entry(queue->txfree.next, struct b43_pio_txpacket, list);
packet->skb = skb;
memset(&packet->txstat, 0, sizeof(packet->txstat));
memcpy(&packet->txstat.control, ctl, sizeof(*ctl));
list_move_tail(&packet->list, &queue->txqueue);
queue->nr_txfree--;
queue->nr_tx_packets++;
B43_WARN_ON(queue->nr_txfree >= B43_PIO_MAXTXPACKETS);
tasklet_schedule(&queue->txtask);
return 0;
}
void b43_pio_handle_txstatus(struct b43_wldev *dev,
const struct b43_txstatus *status)
{
struct b43_pioqueue *queue;
struct b43_pio_txpacket *packet;
queue = parse_cookie(dev, status->cookie, &packet);
if (B43_WARN_ON(!queue))
return;
queue->tx_devq_packets--;
queue->tx_devq_used -=
(packet->skb->len + sizeof(struct b43_txhdr_fw4));
if (status->acked) {
packet->txstat.flags |= IEEE80211_TX_STATUS_ACK;
} else {
if (!(packet->txstat.control.flags & IEEE80211_TXCTL_NO_ACK))
packet->txstat.excessive_retries = 1;
}
if (status->frame_count == 0) {
/* The frame was not transmitted at all. */
packet->txstat.retry_count = 0;
} else
packet->txstat.retry_count = status->frame_count - 1;
ieee80211_tx_status_irqsafe(dev->wl->hw, packet->skb,
&(packet->txstat));
packet->skb = NULL;
free_txpacket(packet);
/* If there are packets on the txqueue, poke the tasklet
* to transmit them.
*/
if (!list_empty(&queue->txqueue))
tasklet_schedule(&queue->txtask);
}
void b43_pio_get_tx_stats(struct b43_wldev *dev,
struct ieee80211_tx_queue_stats *stats)
{
struct b43_pio *pio = &dev->pio;
struct b43_pioqueue *queue;
struct ieee80211_tx_queue_stats_data *data;
queue = pio->queue1;
data = &(stats->data[0]);
data->len = B43_PIO_MAXTXPACKETS - queue->nr_txfree;
data->limit = B43_PIO_MAXTXPACKETS;
data->count = queue->nr_tx_packets;
}
static void pio_rx_error(struct b43_pioqueue *queue,
int clear_buffers, const char *error)
{
int i;
b43err(queue->dev->wl, "PIO RX error: %s\n", error);
b43_pio_write(queue, B43_PIO_RXCTL, B43_PIO_RXCTL_READY);
if (clear_buffers) {
B43_WARN_ON(queue->mmio_base != B43_MMIO_PIO1_BASE);
for (i = 0; i < 15; i++) {
/* Dummy read. */
b43_pio_read(queue, B43_PIO_RXDATA);
}
}
}
void b43_pio_rx(struct b43_pioqueue *queue)
{
__le16 preamble[21] = { 0 };
struct b43_rxhdr_fw4 *rxhdr;
u16 tmp, len;
u32 macstat;
int i, preamble_readwords;
struct sk_buff *skb;
tmp = b43_pio_read(queue, B43_PIO_RXCTL);
if (!(tmp & B43_PIO_RXCTL_DATAAVAILABLE))
return;
b43_pio_write(queue, B43_PIO_RXCTL, B43_PIO_RXCTL_DATAAVAILABLE);
for (i = 0; i < 10; i++) {
tmp = b43_pio_read(queue, B43_PIO_RXCTL);
if (tmp & B43_PIO_RXCTL_READY)
goto data_ready;
udelay(10);
}
b43dbg(queue->dev->wl, "PIO RX timed out\n");
return;
data_ready:
len = b43_pio_read(queue, B43_PIO_RXDATA);
if (unlikely(len > 0x700)) {
pio_rx_error(queue, 0, "len > 0x700");
return;
}
if (unlikely(len == 0 && queue->mmio_base != B43_MMIO_PIO4_BASE)) {
pio_rx_error(queue, 0, "len == 0");
return;
}
preamble[0] = cpu_to_le16(len);
if (queue->mmio_base == B43_MMIO_PIO4_BASE)
preamble_readwords = 14 / sizeof(u16);
else
preamble_readwords = 18 / sizeof(u16);
for (i = 0; i < preamble_readwords; i++) {
tmp = b43_pio_read(queue, B43_PIO_RXDATA);
preamble[i + 1] = cpu_to_le16(tmp);
}
rxhdr = (struct b43_rxhdr_fw4 *)preamble;
macstat = le32_to_cpu(rxhdr->mac_status);
if (macstat & B43_RX_MAC_FCSERR) {
pio_rx_error(queue,
(queue->mmio_base == B43_MMIO_PIO1_BASE),
"Frame FCS error");
return;
}
if (queue->mmio_base == B43_MMIO_PIO4_BASE) {
/* We received an xmit status. */
struct b43_hwtxstatus *hw;
hw = (struct b43_hwtxstatus *)(preamble + 1);
b43_handle_hwtxstatus(queue->dev, hw);
return;
}
skb = dev_alloc_skb(len);
if (unlikely(!skb)) {
pio_rx_error(queue, 1, "OOM");
return;
}
skb_put(skb, len);
for (i = 0; i < len - 1; i += 2) {
tmp = b43_pio_read(queue, B43_PIO_RXDATA);
*((__le16 *)(skb->data + i)) = cpu_to_le16(tmp);
}
if (len % 2) {
tmp = b43_pio_read(queue, B43_PIO_RXDATA);
skb->data[len - 1] = (tmp & 0x00FF);
/* The specs say the following is required, but
* it is wrong and corrupts the PLCP. If we don't do
* this, the PLCP seems to be correct. So ifdef it out for now.
*/
#if 0
if (rxflags2 & B43_RXHDR_FLAGS2_TYPE2FRAME)
skb->data[2] = (tmp & 0xFF00) >> 8;
else
skb->data[0] = (tmp & 0xFF00) >> 8;
#endif
}
b43_rx(queue->dev, skb, rxhdr);
}
void b43_pio_tx_suspend(struct b43_pioqueue *queue)
{
b43_power_saving_ctl_bits(queue->dev, B43_PS_AWAKE);
b43_pio_write(queue, B43_PIO_TXCTL, b43_pio_read(queue, B43_PIO_TXCTL)
| B43_PIO_TXCTL_SUSPEND);
}
void b43_pio_tx_resume(struct b43_pioqueue *queue)
{
b43_pio_write(queue, B43_PIO_TXCTL, b43_pio_read(queue, B43_PIO_TXCTL)
& ~B43_PIO_TXCTL_SUSPEND);
b43_power_saving_ctl_bits(queue->dev, 0);
tasklet_schedule(&queue->txtask);
}
void b43_pio_freeze_txqueues(struct b43_wldev *dev)
{
struct b43_pio *pio;
B43_WARN_ON(!b43_using_pio(dev));
pio = &dev->pio;
pio->queue0->tx_frozen = 1;
pio->queue1->tx_frozen = 1;
pio->queue2->tx_frozen = 1;
pio->queue3->tx_frozen = 1;
}
void b43_pio_thaw_txqueues(struct b43_wldev *dev)
{
struct b43_pio *pio;
B43_WARN_ON(!b43_using_pio(dev));
pio = &dev->pio;
pio->queue0->tx_frozen = 0;
pio->queue1->tx_frozen = 0;
pio->queue2->tx_frozen = 0;
pio->queue3->tx_frozen = 0;
if (!list_empty(&pio->queue0->txqueue))
tasklet_schedule(&pio->queue0->txtask);
if (!list_empty(&pio->queue1->txqueue))
tasklet_schedule(&pio->queue1->txtask);
if (!list_empty(&pio->queue2->txqueue))
tasklet_schedule(&pio->queue2->txtask);
if (!list_empty(&pio->queue3->txqueue))
tasklet_schedule(&pio->queue3->txtask);
}
