diff options
Diffstat (limited to 'drivers/net/wireless/bcm43xx/bcm43xx_pio.c')
| -rw-r--r-- | drivers/net/wireless/bcm43xx/bcm43xx_pio.c | 592 |
1 files changed, 592 insertions, 0 deletions
diff --git a/drivers/net/wireless/bcm43xx/bcm43xx_pio.c b/drivers/net/wireless/bcm43xx/bcm43xx_pio.c new file mode 100644 index 0000000000000..9a55e9d005284 --- /dev/null +++ b/drivers/net/wireless/bcm43xx/bcm43xx_pio.c @@ -0,0 +1,592 @@ +/* + + Broadcom BCM43xx wireless driver + + PIO Transmission + + Copyright (c) 2005 Michael Buesch <mbuesch@freenet.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 "bcm43xx.h" +#include "bcm43xx_pio.h" +#include "bcm43xx_main.h" + +#include <linux/delay.h> + + +static inline +u16 bcm43xx_pio_read(struct bcm43xx_pioqueue *queue, + u16 offset) +{ + return bcm43xx_read16(queue->bcm, queue->mmio_base + offset); +} + +static inline +void bcm43xx_pio_write(struct bcm43xx_pioqueue *queue, + u16 offset, u16 value) +{ + bcm43xx_write16(queue->bcm, queue->mmio_base + offset, value); +} + +static inline +void tx_start(struct bcm43xx_pioqueue *queue) +{ + bcm43xx_pio_write(queue, BCM43xx_PIO_TXCTL, BCM43xx_PIO_TXCTL_INIT); +} + +static inline +void tx_octet(struct bcm43xx_pioqueue *queue, + u8 octet) +{ + if (queue->bcm->current_core->rev < 3) { + bcm43xx_pio_write(queue, BCM43xx_PIO_TXDATA, octet); + bcm43xx_pio_write(queue, BCM43xx_PIO_TXCTL, BCM43xx_PIO_TXCTL_WRITEHI); + } else { + bcm43xx_pio_write(queue, BCM43xx_PIO_TXCTL, BCM43xx_PIO_TXCTL_WRITEHI); + bcm43xx_pio_write(queue, BCM43xx_PIO_TXDATA, octet); + } +} + +static inline +void tx_data(struct bcm43xx_pioqueue *queue, + u8 *packet, + unsigned int octets) +{ + u16 data; + unsigned int i = 0; + + if (queue->bcm->current_core->rev < 3) { + data = be16_to_cpu( *((u16 *)packet) ); + bcm43xx_pio_write(queue, BCM43xx_PIO_TXDATA, data); + i += 2; + } + bcm43xx_pio_write(queue, BCM43xx_PIO_TXCTL, + BCM43xx_PIO_TXCTL_WRITELO | BCM43xx_PIO_TXCTL_WRITEHI); + for ( ; i < octets - 1; i += 2) { + data = be16_to_cpu( *((u16 *)(packet + i)) ); + bcm43xx_pio_write(queue, BCM43xx_PIO_TXDATA, data); + } + if (octets % 2) + tx_octet(queue, packet[octets - 1]); +} + +static inline +void tx_complete(struct bcm43xx_pioqueue *queue, + struct sk_buff *skb) +{ + u16 data; + + if (queue->bcm->current_core->rev < 3) { + data = be16_to_cpu( *((u16 *)(skb->data + skb->len - 2)) ); + bcm43xx_pio_write(queue, BCM43xx_PIO_TXDATA, data); + bcm43xx_pio_write(queue, BCM43xx_PIO_TXCTL, + BCM43xx_PIO_TXCTL_WRITEHI | BCM43xx_PIO_TXCTL_COMPLETE); + } else { + bcm43xx_pio_write(queue, BCM43xx_PIO_TXCTL, BCM43xx_PIO_TXCTL_COMPLETE); + } +} + +static inline +u16 generate_cookie(struct bcm43xx_pioqueue *queue, + int packetindex) +{ + u16 cookie = 0x0000; + + /* 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) { + default: + assert(0); + case BCM43xx_MMIO_PIO1_BASE: + break; + case BCM43xx_MMIO_PIO2_BASE: + cookie = 0x1000; + break; + case BCM43xx_MMIO_PIO3_BASE: + cookie = 0x2000; + break; + case BCM43xx_MMIO_PIO4_BASE: + cookie = 0x3000; + break; + } + assert(((u16)packetindex & 0xF000) == 0x0000); + cookie |= (u16)packetindex; + + return cookie; +} + +static inline +struct bcm43xx_pioqueue * parse_cookie(struct bcm43xx_private *bcm, + u16 cookie, + struct bcm43xx_pio_txpacket **packet) +{ + struct bcm43xx_pioqueue *queue = NULL; + int packetindex; + + switch (cookie & 0xF000) { + case 0x0000: + queue = bcm->current_core->pio->queue0; + break; + case 0x1000: + queue = bcm->current_core->pio->queue1; + break; + case 0x2000: + queue = bcm->current_core->pio->queue2; + break; + case 0x3000: + queue = bcm->current_core->pio->queue3; + break; + default: + assert(0); + } + + packetindex = (cookie & 0x0FFF); + assert(packetindex >= 0 && packetindex < BCM43xx_PIO_MAXTXPACKETS); + *packet = queue->__tx_packets_cache + packetindex; + + return queue; +} + +static inline +void pio_tx_write_fragment(struct bcm43xx_pioqueue *queue, + struct sk_buff *skb, + struct bcm43xx_pio_txpacket *packet) +{ + unsigned int octets; + + assert(skb_shinfo(skb)->nr_frags == 0); + assert(skb_headroom(skb) >= sizeof(struct bcm43xx_txhdr)); + + __skb_push(skb, sizeof(struct bcm43xx_txhdr)); + bcm43xx_generate_txhdr(queue->bcm, + (struct bcm43xx_txhdr *)skb->data, + skb->data + sizeof(struct bcm43xx_txhdr), + skb->len - sizeof(struct bcm43xx_txhdr), + (packet->xmitted_frags == 0), + generate_cookie(queue, pio_txpacket_getindex(packet))); + + tx_start(queue); + octets = skb->len; + if (queue->bcm->current_core->rev < 3) //FIXME: && this is the last packet in the queue. + octets -= 2; + tx_data(queue, (u8 *)skb->data, octets); + tx_complete(queue, skb); +} + +static inline +int pio_tx_packet(struct bcm43xx_pio_txpacket *packet) +{ + struct bcm43xx_pioqueue *queue = packet->queue; + struct ieee80211_txb *txb = packet->txb; + struct sk_buff *skb; + u16 octets; + int i; + + for (i = packet->xmitted_frags; i < txb->nr_frags; i++) { + skb = txb->fragments[i]; + + octets = (u16)skb->len + sizeof(struct bcm43xx_txhdr); + + assert(queue->tx_devq_size >= octets); + assert(queue->tx_devq_packets <= BCM43xx_PIO_MAXTXDEVQPACKETS); + assert(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-work-handler + * retry later. + */ + if (queue->tx_devq_packets == BCM43xx_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); + + /* Account for the packet size. + * (We must not overflow the device TX queue) + */ + queue->tx_devq_packets++; + queue->tx_devq_used += octets; + + assert(packet->xmitted_frags <= packet->txb->nr_frags); + packet->xmitted_frags++; + packet->xmitted_octets += octets; + } + list_move_tail(&packet->list, &queue->txrunning); + + return 0; +} + +static void free_txpacket(struct bcm43xx_pio_txpacket *packet) +{ + struct bcm43xx_pioqueue *queue = packet->queue; + + ieee80211_txb_free(packet->txb); + + list_move(&packet->list, &packet->queue->txfree); + + assert(queue->tx_devq_used >= packet->xmitted_octets); + queue->tx_devq_used -= packet->xmitted_octets; + assert(queue->tx_devq_packets >= packet->xmitted_frags); + queue->tx_devq_packets -= packet->xmitted_frags; +} + +static void txwork_handler(void *d) +{ + struct bcm43xx_pioqueue *queue = d; + unsigned long flags; + struct bcm43xx_pio_txpacket *packet, *tmp_packet; + int err; + + spin_lock_irqsave(&queue->txlock, flags); + list_for_each_entry_safe(packet, tmp_packet, &queue->txqueue, list) { + assert(packet->xmitted_frags < packet->txb->nr_frags); + if (packet->xmitted_frags == 0) { + int i; + struct sk_buff *skb; + + /* Check if the device queue is big + * enough for every fragment. If not, drop the + * whole packet. + */ + for (i = 0; i < packet->txb->nr_frags; i++) { + skb = packet->txb->fragments[i]; + if (unlikely(skb->len > queue->tx_devq_size)) { + dprintkl(KERN_ERR PFX "PIO TX device queue too small. " + "Dropping packet...\n"); + free_txpacket(packet); + goto next_packet; + } + } + } + /* Now try to transmit the packet. + * This may not completely succeed. + */ + err = pio_tx_packet(packet); + if (err) + break; +next_packet: + continue; + } + spin_unlock_irqrestore(&queue->txlock, flags); +} + +static void setup_txqueues(struct bcm43xx_pioqueue *queue) +{ + struct bcm43xx_pio_txpacket *packet; + int i; + + for (i = 0; i < BCM43xx_PIO_MAXTXPACKETS; i++) { + packet = queue->__tx_packets_cache + i; + + packet->queue = queue; + INIT_LIST_HEAD(&packet->list); + + list_add(&packet->list, &queue->txfree); + } +} + +static +struct bcm43xx_pioqueue * bcm43xx_setup_pioqueue(struct bcm43xx_private *bcm, + u16 pio_mmio_base) +{ + struct bcm43xx_pioqueue *queue; + u32 value; + u16 qsize; + + queue = kmalloc(sizeof(*queue), GFP_KERNEL); + if (!queue) + goto out; + memset(queue, 0, sizeof(*queue)); + + queue->bcm = bcm; + queue->mmio_base = pio_mmio_base; + + INIT_LIST_HEAD(&queue->txfree); + INIT_LIST_HEAD(&queue->txqueue); + INIT_LIST_HEAD(&queue->txrunning); + spin_lock_init(&queue->txlock); + INIT_WORK(&queue->txwork, txwork_handler, queue); + + value = bcm43xx_read32(bcm, BCM43xx_MMIO_STATUS_BITFIELD); + value |= BCM43xx_SBF_XFER_REG_BYTESWAP; + bcm43xx_write32(bcm, BCM43xx_MMIO_STATUS_BITFIELD, value); + + qsize = bcm43xx_read16(bcm, queue->mmio_base + BCM43xx_PIO_TXQBUFSIZE); + if (qsize <= BCM43xx_PIO_TXQADJUST) { + printk(KERN_ERR PFX "PIO tx queue too small (%u)\n", qsize); + goto err_freequeue; + } + qsize -= BCM43xx_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 bcm43xx_pioqueue *queue) +{ + struct bcm43xx_pio_txpacket *packet, *tmp_packet; + + netif_tx_disable(queue->bcm->net_dev); + assert(queue->bcm->shutting_down); + cancel_delayed_work(&queue->txwork); + flush_workqueue(queue->bcm->workqueue); + + 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 bcm43xx_destroy_pioqueue(struct bcm43xx_pioqueue *queue) +{ + if (!queue) + return; + + cancel_transfers(queue); + kfree(queue); +} + +void bcm43xx_pio_free(struct bcm43xx_private *bcm) +{ + bcm43xx_destroy_pioqueue(bcm->current_core->pio->queue3); + bcm->current_core->pio->queue3 = NULL; + bcm43xx_destroy_pioqueue(bcm->current_core->pio->queue2); + bcm->current_core->pio->queue2 = NULL; + bcm43xx_destroy_pioqueue(bcm->current_core->pio->queue1); + bcm->current_core->pio->queue1 = NULL; + bcm43xx_destroy_pioqueue(bcm->current_core->pio->queue0); + bcm->current_core->pio->queue0 = NULL; +} + +int bcm43xx_pio_init(struct bcm43xx_private *bcm) +{ + struct bcm43xx_pioqueue *queue; + int err = -ENOMEM; + + queue = bcm43xx_setup_pioqueue(bcm, BCM43xx_MMIO_PIO1_BASE); + if (!queue) + goto out; + bcm->current_core->pio->queue0 = queue; + + queue = bcm43xx_setup_pioqueue(bcm, BCM43xx_MMIO_PIO2_BASE); + if (!queue) + goto err_destroy0; + bcm->current_core->pio->queue1 = queue; + + queue = bcm43xx_setup_pioqueue(bcm, BCM43xx_MMIO_PIO3_BASE); + if (!queue) + goto err_destroy1; + bcm->current_core->pio->queue2 = queue; + + queue = bcm43xx_setup_pioqueue(bcm, BCM43xx_MMIO_PIO4_BASE); + if (!queue) + goto err_destroy2; + bcm->current_core->pio->queue3 = queue; + + if (bcm->current_core->rev < 3) + bcm->irq_savedstate |= BCM43xx_IRQ_PIO_WORKAROUND; + + dprintk(KERN_INFO PFX "PIO initialized\n"); + err = 0; +out: + return err; + +err_destroy2: + bcm43xx_destroy_pioqueue(bcm->current_core->pio->queue2); + bcm->current_core->pio->queue2 = NULL; +err_destroy1: + bcm43xx_destroy_pioqueue(bcm->current_core->pio->queue1); + bcm->current_core->pio->queue1 = NULL; +err_destroy0: + bcm43xx_destroy_pioqueue(bcm->current_core->pio->queue0); + bcm->current_core->pio->queue0 = NULL; + goto out; +} + +static inline +int pio_transfer_txb(struct bcm43xx_pioqueue *queue, + struct ieee80211_txb *txb) +{ + struct bcm43xx_pio_txpacket *packet; + unsigned long flags; + u16 tmp; + + spin_lock_irqsave(&queue->txlock, flags); + assert(!queue->tx_suspended); + assert(!list_empty(&queue->txfree)); + + tmp = bcm43xx_pio_read(queue, BCM43xx_PIO_TXCTL); + if (tmp & BCM43xx_PIO_TXCTL_SUSPEND) { + spin_unlock_irqrestore(&queue->txlock, flags); + return -EBUSY; + } + + packet = list_entry(queue->txfree.next, struct bcm43xx_pio_txpacket, list); + + packet->txb = txb; + list_move_tail(&packet->list, &queue->txqueue); + packet->xmitted_octets = 0; + packet->xmitted_frags = 0; + + /* Suspend TX, if we are out of packets in the "free" queue. */ + if (unlikely(list_empty(&queue->txfree))) { + netif_stop_queue(queue->bcm->net_dev); + queue->tx_suspended = 1; + } + + spin_unlock_irqrestore(&queue->txlock, flags); + queue_work(queue->bcm->workqueue, &queue->txwork); + + return 0; +} + +int fastcall bcm43xx_pio_transfer_txb(struct bcm43xx_private *bcm, + struct ieee80211_txb *txb) +{ + return pio_transfer_txb(bcm->current_core->pio->queue1, txb); +} + +void fastcall +bcm43xx_pio_handle_xmitstatus(struct bcm43xx_private *bcm, + struct bcm43xx_xmitstatus *status) +{ + struct bcm43xx_pioqueue *queue; + struct bcm43xx_pio_txpacket *packet; + unsigned long flags; + + queue = parse_cookie(bcm, status->cookie, &packet); + assert(queue); + spin_lock_irqsave(&queue->txlock, flags); + free_txpacket(packet); + if (unlikely(queue->tx_suspended)) { + queue->tx_suspended = 0; + netif_wake_queue(queue->bcm->net_dev); + } + + /* If there are packets on the txqueue, + * start the work handler again. + */ + if (!list_empty(&queue->txqueue)) { + queue_work(queue->bcm->workqueue, + &queue->txwork); + } + spin_unlock_irqrestore(&queue->txlock, flags); +} + +static void pio_rx_error(struct bcm43xx_pioqueue *queue, + const char *error) +{ + printk("PIO RX error: %s\n", error); + bcm43xx_pio_write(queue, BCM43xx_PIO_RXCTL, BCM43xx_PIO_RXCTL_READY); +} + +void fastcall +bcm43xx_pio_rx(struct bcm43xx_pioqueue *queue) +{ + u16 preamble[21] = { 0 }; + struct bcm43xx_rxhdr *rxhdr; + u16 tmp; + u16 len; + int i, err; + int preamble_readwords; + struct sk_buff *skb; + + tmp = bcm43xx_pio_read(queue, BCM43xx_PIO_RXCTL); + if (!(tmp & BCM43xx_PIO_RXCTL_DATAAVAILABLE)) { + dprintkl(KERN_ERR PFX "PIO RX: No data available\n"); + return; + } + bcm43xx_pio_write(queue, BCM43xx_PIO_RXCTL, BCM43xx_PIO_RXCTL_DATAAVAILABLE); + + for (i = 0; i < 10; i++) { + tmp = bcm43xx_pio_read(queue, BCM43xx_PIO_RXCTL); + if (tmp & BCM43xx_PIO_RXCTL_READY) + goto data_ready; + udelay(10); + } + dprintkl(KERN_ERR PFX "PIO RX timed out\n"); + return; +data_ready: + + len = le16_to_cpu(bcm43xx_pio_read(queue, BCM43xx_PIO_RXDATA)); + if (unlikely(len > 0x700)) { + pio_rx_error(queue, "len > 0x700"); + return; + } + if (unlikely(len == 0 && queue->mmio_base != BCM43xx_MMIO_PIO4_BASE)) { + pio_rx_error(queue, "len == 0"); + return; + } + preamble[0] = cpu_to_le16(len); + if (queue->mmio_base == BCM43xx_MMIO_PIO4_BASE) + preamble_readwords = 14 / sizeof(u16); + else + preamble_readwords = 18 / sizeof(u16); + for (i = 0; i < preamble_readwords; i++) { + tmp = bcm43xx_pio_read(queue, BCM43xx_PIO_RXDATA); + preamble[i + 1] = cpu_to_be16(tmp); + } + rxhdr = (struct bcm43xx_rxhdr *)preamble; + if (unlikely(rxhdr->flags2 & BCM43xx_RXHDR_FLAGS2_INVALIDFRAME)) { + pio_rx_error(queue, "invalid frame"); + if (queue->mmio_base == BCM43xx_MMIO_PIO1_BASE) { + for (i = 0; i < 15; i++) + bcm43xx_pio_read(queue, BCM43xx_PIO_RXDATA); /* dummy read. */ + } + return; + } +//FIXME +#if 0 + if (queue->mmio_base == BCM43xx_MMIO_PIO4_BASE) { + bcm43xx_rx_transmitstatus(queue->bcm, + (const struct bcm43xx_hwxmitstatus *)(preamble + 1)); + return; + } +#endif + skb = dev_alloc_skb(len); + if (unlikely(!skb)) { + pio_rx_error(queue, "out of memory"); + return; + } + skb_put(skb, len); + for (i = 0; i < len - 1; i += 2) { + tmp = cpu_to_be16(bcm43xx_pio_read(queue, BCM43xx_PIO_RXDATA)); + *((u16 *)(skb->data + i)) = tmp; + } + if (len % 2) { + tmp = cpu_to_be16(bcm43xx_pio_read(queue, BCM43xx_PIO_RXDATA)); + skb->data[len - 1] = (tmp & 0x00FF); + skb->data[0] = (tmp & 0xFF00) >> 8; + } + err = bcm43xx_rx(queue->bcm, skb, rxhdr); + if (unlikely(err)) + dev_kfree_skb_irq(skb); +} + +/* vim: set ts=8 sw=8 sts=8: */ |