b43: finish removal of pio support

/*

  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);

}

#ifndef B43_PIO_H_

#define B43_PIO_H_

#include "b43.h"

#include <linux/interrupt.h>

#include <linux/io.h>

#include <linux/list.h>

#include <linux/skbuff.h>

#define B43_PIO_TXCTL		0x00

#define B43_PIO_TXDATA		0x02

#define B43_PIO_TXQBUFSIZE		0x04

#define B43_PIO_RXCTL		0x08

#define B43_PIO_RXDATA		0x0A

#define B43_PIO_TXCTL_WRITELO	(1 << 0)

#define B43_PIO_TXCTL_WRITEHI	(1 << 1)

#define B43_PIO_TXCTL_COMPLETE	(1 << 2)

#define B43_PIO_TXCTL_INIT		(1 << 3)

#define B43_PIO_TXCTL_SUSPEND	(1 << 7)

#define B43_PIO_RXCTL_DATAAVAILABLE	(1 << 0)

#define B43_PIO_RXCTL_READY		(1 << 1)

/* PIO constants */

#define B43_PIO_MAXTXDEVQPACKETS	31

#define B43_PIO_TXQADJUST		80

/* PIO tuning knobs */

#define B43_PIO_MAXTXPACKETS	256

#ifdef CONFIG_B43_PIO

struct b43_pioqueue;

struct b43_xmitstatus;

struct b43_pio_txpacket {