/*
* Common code for mac80211 Prism54 drivers
*
* Copyright (c) 2006, Michael Wu <flamingice@sourmilk.net>
* Copyright (c) 2007-2009, Christian Lamparter <chunkeey@web.de>
* Copyright 2008, Johannes Berg <johannes@sipsolutions.net>
*
* Based on:
* - the islsm (softmac prism54) driver, which is:
* Copyright 2004-2006 Jean-Baptiste Note <jbnote@gmail.com>, et al.
* - stlc45xx driver
* Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies).
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/export.h>
#include <linux/firmware.h>
#include <linux/etherdevice.h>
#include <asm/div64.h>
#include <net/mac80211.h>
#include "p54.h"
#include "lmac.h"
#ifdef P54_MM_DEBUG
static void p54_dump_tx_queue(struct p54_common *priv)
{
unsigned long flags;
struct ieee80211_tx_info *info;
struct p54_tx_info *range;
struct sk_buff *skb;
struct p54_hdr *hdr;
unsigned int i = 0;
u32 prev_addr;
u32 largest_hole = 0, free;
spin_lock_irqsave(&priv->tx_queue.lock, flags);
wiphy_debug(priv->hw->wiphy, "/ --- tx queue dump (%d entries) ---\n",
skb_queue_len(&priv->tx_queue));
prev_addr = priv->rx_start;
skb_queue_walk(&priv->tx_queue, skb) {
info = IEEE80211_SKB_CB(skb);
range = (void *) info->rate_driver_data;
hdr = (void *) skb->data;
free = range->start_addr - prev_addr;
wiphy_debug(priv->hw->wiphy,
"| [%02d] => [skb:%p skb_len:0x%04x "
"hdr:{flags:%02x len:%04x req_id:%04x type:%02x} "
"mem:{start:%04x end:%04x, free:%d}]\n",
i++, skb, skb->len,
le16_to_cpu(hdr->flags), le16_to_cpu(hdr->len),
le32_to_cpu(hdr->req_id), le16_to_cpu(hdr->type),
range->start_addr, range->end_addr, free);
prev_addr = range->end_addr;
largest_hole = max(largest_hole, free);
}
free = priv->rx_end - prev_addr;
largest_hole = max(largest_hole, free);
wiphy_debug(priv->hw->wiphy,
"\\ --- [free: %d], largest free block: %d ---\n",
free, largest_hole);
spin_unlock_irqrestore(&priv->tx_queue.lock, flags);
}
#endif /* P54_MM_DEBUG */
/*
* So, the firmware is somewhat stupid and doesn't know what places in its
* memory incoming data should go to. By poking around in the firmware, we
* can find some unused memory to upload our packets to. However, data that we
* want the card to TX needs to stay intact until the card has told us that
* it is done with it. This function finds empty places we can upload to and
* marks allocated areas as reserved if necessary. p54_find_and_unlink_skb or
* p54_free_skb frees allocated areas.
*/
static int p54_assign_address(struct p54_common *priv, struct sk_buff *skb)
{
struct sk_buff *entry, *target_skb = NULL;
struct ieee80211_tx_info *info;
struct p54_tx_info *range;
struct p54_hdr *data = (void *) skb->data;
unsigned long flags;
u32 last_addr = priv->rx_start;
u32 target_addr = priv->rx_start;
u16 len = priv->headroom + skb->len + priv->tailroom + 3;
info = IEEE80211_SKB_CB(skb);
range = (void *) info->rate_driver_data;
len = (range->extra_len + len) & ~0x3;
spin_lock_irqsave(&priv->tx_queue.lock, flags);
if (unlikely(skb_queue_len(&priv->tx_queue) == 32)) {
/*
* The tx_queue is now really full.
*
* TODO: check if the device has crashed and reset it.
*/
spin_unlock_irqrestore(&priv->tx_queue.lock, flags);
return -EBUSY;
}
skb_queue_walk(&priv->tx_queue, entry) {
u32 hole_size;
info = IEEE80211_SKB_CB(entry);
range = (void *) info->rate_driver_data;
hole_size = range->start_addr - last_addr;
if (!target_skb && hole_size >= len) {
target_skb = entry->prev;
hole_size -= len;
target_addr = last_addr;
break;
}
last_addr = range->end_addr;
}
if (unlikely(!target_skb)) {
if (priv->rx_end - last_addr >= len) {
target_skb = priv->tx_queue.prev;
if (!skb_queue_empty(&priv->tx_queue)) {
info = IEEE80211_SKB_CB(target_skb);
range = (void *)info->rate_driver_data;
target_addr = range->end_addr;
}
} else {
spin_unlock_irqrestore(&priv->tx_queue.lock, flags);
return -ENOSPC;
}
}
info = IEEE80211_SKB_CB(skb);