diff options
Diffstat (limited to 'drivers/net/wireless/b43/pio.c')
| -rw-r--r-- | drivers/net/wireless/b43/pio.c | 652 |
1 files changed, 652 insertions, 0 deletions
diff --git a/drivers/net/wireless/b43/pio.c b/drivers/net/wireless/b43/pio.c new file mode 100644 index 0000000..67752a2 --- /dev/null +++ b/drivers/net/wireless/b43/pio.c @@ -0,0 +1,652 @@ +/* + + 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); +} |