diff options
Diffstat (limited to 'drivers/net/wireless/wl1251/tx.c')
-rw-r--r-- | drivers/net/wireless/wl1251/tx.c | 570 |
1 files changed, 570 insertions, 0 deletions
diff --git a/drivers/net/wireless/wl1251/tx.c b/drivers/net/wireless/wl1251/tx.c new file mode 100644 index 000000000000..554b4f9a3d3e --- /dev/null +++ b/drivers/net/wireless/wl1251/tx.c @@ -0,0 +1,570 @@ +/* + * This file is part of wl1251 + * + * Copyright (c) 1998-2007 Texas Instruments Incorporated + * Copyright (C) 2008 Nokia Corporation + * + * 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. + * + * 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; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA + * 02110-1301 USA + * + */ + +#include <linux/kernel.h> +#include <linux/module.h> + +#include "wl1251.h" +#include "reg.h" +#include "tx.h" +#include "ps.h" +#include "io.h" + +static bool wl1251_tx_double_buffer_busy(struct wl1251 *wl, u32 data_out_count) +{ + int used, data_in_count; + + data_in_count = wl->data_in_count; + + if (data_in_count < data_out_count) + /* data_in_count has wrapped */ + data_in_count += TX_STATUS_DATA_OUT_COUNT_MASK + 1; + + used = data_in_count - data_out_count; + + WARN_ON(used < 0); + WARN_ON(used > DP_TX_PACKET_RING_CHUNK_NUM); + + if (used >= DP_TX_PACKET_RING_CHUNK_NUM) + return true; + else + return false; +} + +static int wl1251_tx_path_status(struct wl1251 *wl) +{ + u32 status, addr, data_out_count; + bool busy; + + addr = wl->data_path->tx_control_addr; + status = wl1251_mem_read32(wl, addr); + data_out_count = status & TX_STATUS_DATA_OUT_COUNT_MASK; + busy = wl1251_tx_double_buffer_busy(wl, data_out_count); + + if (busy) + return -EBUSY; + + return 0; +} + +static int wl1251_tx_id(struct wl1251 *wl, struct sk_buff *skb) +{ + int i; + + for (i = 0; i < FW_TX_CMPLT_BLOCK_SIZE; i++) + if (wl->tx_frames[i] == NULL) { + wl->tx_frames[i] = skb; + return i; + } + + return -EBUSY; +} + +static void wl1251_tx_control(struct tx_double_buffer_desc *tx_hdr, + struct ieee80211_tx_info *control, u16 fc) +{ + *(u16 *)&tx_hdr->control = 0; + + tx_hdr->control.rate_policy = 0; + + /* 802.11 packets */ + tx_hdr->control.packet_type = 0; + + if (control->flags & IEEE80211_TX_CTL_NO_ACK) + tx_hdr->control.ack_policy = 1; + + tx_hdr->control.tx_complete = 1; + + if ((fc & IEEE80211_FTYPE_DATA) && + ((fc & IEEE80211_STYPE_QOS_DATA) || + (fc & IEEE80211_STYPE_QOS_NULLFUNC))) + tx_hdr->control.qos = 1; +} + +/* RSN + MIC = 8 + 8 = 16 bytes (worst case - AES). */ +#define MAX_MSDU_SECURITY_LENGTH 16 +#define MAX_MPDU_SECURITY_LENGTH 16 +#define WLAN_QOS_HDR_LEN 26 +#define MAX_MPDU_HEADER_AND_SECURITY (MAX_MPDU_SECURITY_LENGTH + \ + WLAN_QOS_HDR_LEN) +#define HW_BLOCK_SIZE 252 +static void wl1251_tx_frag_block_num(struct tx_double_buffer_desc *tx_hdr) +{ + u16 payload_len, frag_threshold, mem_blocks; + u16 num_mpdus, mem_blocks_per_frag; + + frag_threshold = IEEE80211_MAX_FRAG_THRESHOLD; + tx_hdr->frag_threshold = cpu_to_le16(frag_threshold); + + payload_len = le16_to_cpu(tx_hdr->length) + MAX_MSDU_SECURITY_LENGTH; + + if (payload_len > frag_threshold) { + mem_blocks_per_frag = + ((frag_threshold + MAX_MPDU_HEADER_AND_SECURITY) / + HW_BLOCK_SIZE) + 1; + num_mpdus = payload_len / frag_threshold; + mem_blocks = num_mpdus * mem_blocks_per_frag; + payload_len -= num_mpdus * frag_threshold; + num_mpdus++; + + } else { + mem_blocks_per_frag = 0; + mem_blocks = 0; + num_mpdus = 1; + } + + mem_blocks += (payload_len / HW_BLOCK_SIZE) + 1; + + if (num_mpdus > 1) + mem_blocks += min(num_mpdus, mem_blocks_per_frag); + + tx_hdr->num_mem_blocks = mem_blocks; +} + +static int wl1251_tx_fill_hdr(struct wl1251 *wl, struct sk_buff *skb, + struct ieee80211_tx_info *control) +{ + struct tx_double_buffer_desc *tx_hdr; + struct ieee80211_rate *rate; + int id; + u16 fc; + + if (!skb) + return -EINVAL; + + id = wl1251_tx_id(wl, skb); + if (id < 0) + return id; + + fc = *(u16 *)skb->data; + tx_hdr = (struct tx_double_buffer_desc *) skb_push(skb, + sizeof(*tx_hdr)); + + tx_hdr->length = cpu_to_le16(skb->len - sizeof(*tx_hdr)); + rate = ieee80211_get_tx_rate(wl->hw, control); + tx_hdr->rate = cpu_to_le16(rate->hw_value); + tx_hdr->expiry_time = cpu_to_le32(1 << 16); + tx_hdr->id = id; + + tx_hdr->xmit_queue = wl1251_tx_get_queue(skb_get_queue_mapping(skb)); + + wl1251_tx_control(tx_hdr, control, fc); + wl1251_tx_frag_block_num(tx_hdr); + + return 0; +} + +/* We copy the packet to the target */ +static int wl1251_tx_send_packet(struct wl1251 *wl, struct sk_buff *skb, + struct ieee80211_tx_info *control) +{ + struct tx_double_buffer_desc *tx_hdr; + int len; + u32 addr; + + if (!skb) + return -EINVAL; + + tx_hdr = (struct tx_double_buffer_desc *) skb->data; + + if (control->control.hw_key && + control->control.hw_key->cipher == WLAN_CIPHER_SUITE_TKIP) { + int hdrlen; + __le16 fc; + u16 length; + u8 *pos; + + fc = *(__le16 *)(skb->data + sizeof(*tx_hdr)); + length = le16_to_cpu(tx_hdr->length) + WL1251_TKIP_IV_SPACE; + tx_hdr->length = cpu_to_le16(length); + + hdrlen = ieee80211_hdrlen(fc); + + pos = skb_push(skb, WL1251_TKIP_IV_SPACE); + memmove(pos, pos + WL1251_TKIP_IV_SPACE, + sizeof(*tx_hdr) + hdrlen); + } + + /* Revisit. This is a workaround for getting non-aligned packets. + This happens at least with EAPOL packets from the user space. + Our DMA requires packets to be aligned on a 4-byte boundary. + */ + if (unlikely((long)skb->data & 0x03)) { + int offset = (4 - (long)skb->data) & 0x03; + wl1251_debug(DEBUG_TX, "skb offset %d", offset); + + /* check whether the current skb can be used */ + if (!skb_cloned(skb) && (skb_tailroom(skb) >= offset)) { + unsigned char *src = skb->data; + + /* align the buffer on a 4-byte boundary */ + skb_reserve(skb, offset); + memmove(skb->data, src, skb->len); + tx_hdr = (struct tx_double_buffer_desc *) skb->data; + } else { + wl1251_info("No handler, fixme!"); + return -EINVAL; + } + } + + /* Our skb->data at this point includes the HW header */ + len = WL1251_TX_ALIGN(skb->len); + + if (wl->data_in_count & 0x1) + addr = wl->data_path->tx_packet_ring_addr + + wl->data_path->tx_packet_ring_chunk_size; + else + addr = wl->data_path->tx_packet_ring_addr; + + wl1251_mem_write(wl, addr, skb->data, len); + + wl1251_debug(DEBUG_TX, "tx id %u skb 0x%p payload %u rate 0x%x " + "queue %d", tx_hdr->id, skb, tx_hdr->length, + tx_hdr->rate, tx_hdr->xmit_queue); + + return 0; +} + +static void wl1251_tx_trigger(struct wl1251 *wl) +{ + u32 data, addr; + + if (wl->data_in_count & 0x1) { + addr = ACX_REG_INTERRUPT_TRIG_H; + data = INTR_TRIG_TX_PROC1; + } else { + addr = ACX_REG_INTERRUPT_TRIG; + data = INTR_TRIG_TX_PROC0; + } + + wl1251_reg_write32(wl, addr, data); + + /* Bumping data in */ + wl->data_in_count = (wl->data_in_count + 1) & + TX_STATUS_DATA_OUT_COUNT_MASK; +} + +/* caller must hold wl->mutex */ +static int wl1251_tx_frame(struct wl1251 *wl, struct sk_buff *skb) +{ + struct ieee80211_tx_info *info; + int ret = 0; + u8 idx; + + info = IEEE80211_SKB_CB(skb); + + if (info->control.hw_key) { + idx = info->control.hw_key->hw_key_idx; + if (unlikely(wl->default_key != idx)) { + ret = wl1251_acx_default_key(wl, idx); + if (ret < 0) + return ret; + } + } + + ret = wl1251_tx_path_status(wl); + if (ret < 0) + return ret; + + ret = wl1251_tx_fill_hdr(wl, skb, info); + if (ret < 0) + return ret; + + ret = wl1251_tx_send_packet(wl, skb, info); + if (ret < 0) + return ret; + + wl1251_tx_trigger(wl); + + return ret; +} + +void wl1251_tx_work(struct work_struct *work) +{ + struct wl1251 *wl = container_of(work, struct wl1251, tx_work); + struct sk_buff *skb; + bool woken_up = false; + int ret; + + mutex_lock(&wl->mutex); + + if (unlikely(wl->state == WL1251_STATE_OFF)) + goto out; + + while ((skb = skb_dequeue(&wl->tx_queue))) { + if (!woken_up) { + ret = wl1251_ps_elp_wakeup(wl); + if (ret < 0) + goto out; + woken_up = true; + } + + ret = wl1251_tx_frame(wl, skb); + if (ret == -EBUSY) { + skb_queue_head(&wl->tx_queue, skb); + goto out; + } else if (ret < 0) { + dev_kfree_skb(skb); + goto out; + } + } + +out: + if (woken_up) + wl1251_ps_elp_sleep(wl); + + mutex_unlock(&wl->mutex); +} + +static const char *wl1251_tx_parse_status(u8 status) +{ + /* 8 bit status field, one character per bit plus null */ + static char buf[9]; + int i = 0; + + memset(buf, 0, sizeof(buf)); + + if (status & TX_DMA_ERROR) + buf[i++] = 'm'; + if (status & TX_DISABLED) + buf[i++] = 'd'; + if (status & TX_RETRY_EXCEEDED) + buf[i++] = 'r'; + if (status & TX_TIMEOUT) + buf[i++] = 't'; + if (status & TX_KEY_NOT_FOUND) + buf[i++] = 'k'; + if (status & TX_ENCRYPT_FAIL) + buf[i++] = 'e'; + if (status & TX_UNAVAILABLE_PRIORITY) + buf[i++] = 'p'; + + /* bit 0 is unused apparently */ + + return buf; +} + +static void wl1251_tx_packet_cb(struct wl1251 *wl, + struct tx_result *result) +{ + struct ieee80211_tx_info *info; + struct sk_buff *skb; + int hdrlen, ret; + u8 *frame; + + skb = wl->tx_frames[result->id]; + if (skb == NULL) { + wl1251_error("SKB for packet %d is NULL", result->id); + return; + } + + info = IEEE80211_SKB_CB(skb); + + if (!(info->flags & IEEE80211_TX_CTL_NO_ACK) && + (result->status == TX_SUCCESS)) + info->flags |= IEEE80211_TX_STAT_ACK; + + info->status.rates[0].count = result->ack_failures + 1; + wl->stats.retry_count += result->ack_failures; + + /* + * We have to remove our private TX header before pushing + * the skb back to mac80211. + */ + frame = skb_pull(skb, sizeof(struct tx_double_buffer_desc)); + if (info->control.hw_key && + info->control.hw_key->cipher == WLAN_CIPHER_SUITE_TKIP) { + hdrlen = ieee80211_get_hdrlen_from_skb(skb); + memmove(frame + WL1251_TKIP_IV_SPACE, frame, hdrlen); + skb_pull(skb, WL1251_TKIP_IV_SPACE); + } + + wl1251_debug(DEBUG_TX, "tx status id %u skb 0x%p failures %u rate 0x%x" + " status 0x%x (%s)", + result->id, skb, result->ack_failures, result->rate, + result->status, wl1251_tx_parse_status(result->status)); + + + ieee80211_tx_status(wl->hw, skb); + + wl->tx_frames[result->id] = NULL; + + if (wl->tx_queue_stopped) { + wl1251_debug(DEBUG_TX, "cb: queue was stopped"); + + skb = skb_dequeue(&wl->tx_queue); + + /* The skb can be NULL because tx_work might have been + scheduled before the queue was stopped making the + queue empty */ + + if (skb) { + ret = wl1251_tx_frame(wl, skb); + if (ret == -EBUSY) { + /* firmware buffer is still full */ + wl1251_debug(DEBUG_TX, "cb: fw buffer " + "still full"); + skb_queue_head(&wl->tx_queue, skb); + return; + } else if (ret < 0) { + dev_kfree_skb(skb); + return; + } + } + + wl1251_debug(DEBUG_TX, "cb: waking queues"); + ieee80211_wake_queues(wl->hw); + wl->tx_queue_stopped = false; + } +} + +/* Called upon reception of a TX complete interrupt */ +void wl1251_tx_complete(struct wl1251 *wl) +{ + int i, result_index, num_complete = 0; + struct tx_result result[FW_TX_CMPLT_BLOCK_SIZE], *result_ptr; + unsigned long flags; + + if (unlikely(wl->state != WL1251_STATE_ON)) + return; + + /* First we read the result */ + wl1251_mem_read(wl, wl->data_path->tx_complete_addr, + result, sizeof(result)); + + result_index = wl->next_tx_complete; + + for (i = 0; i < ARRAY_SIZE(result); i++) { + result_ptr = &result[result_index]; + + if (result_ptr->done_1 == 1 && + result_ptr->done_2 == 1) { + wl1251_tx_packet_cb(wl, result_ptr); + + result_ptr->done_1 = 0; + result_ptr->done_2 = 0; + + result_index = (result_index + 1) & + (FW_TX_CMPLT_BLOCK_SIZE - 1); + num_complete++; + } else { + break; + } + } + + if (wl->tx_queue_stopped + && + skb_queue_len(&wl->tx_queue) <= WL1251_TX_QUEUE_LOW_WATERMARK){ + + /* firmware buffer has space, restart queues */ + wl1251_debug(DEBUG_TX, "tx_complete: waking queues"); + spin_lock_irqsave(&wl->wl_lock, flags); + ieee80211_wake_queues(wl->hw); + wl->tx_queue_stopped = false; + spin_unlock_irqrestore(&wl->wl_lock, flags); + ieee80211_queue_work(wl->hw, &wl->tx_work); + + } + + /* Every completed frame needs to be acknowledged */ + if (num_complete) { + /* + * If we've wrapped, we have to clear + * the results in 2 steps. + */ + if (result_index > wl->next_tx_complete) { + /* Only 1 write is needed */ + wl1251_mem_write(wl, + wl->data_path->tx_complete_addr + + (wl->next_tx_complete * + sizeof(struct tx_result)), + &result[wl->next_tx_complete], + num_complete * + sizeof(struct tx_result)); + + + } else if (result_index < wl->next_tx_complete) { + /* 2 writes are needed */ + wl1251_mem_write(wl, + wl->data_path->tx_complete_addr + + (wl->next_tx_complete * + sizeof(struct tx_result)), + &result[wl->next_tx_complete], + (FW_TX_CMPLT_BLOCK_SIZE - + wl->next_tx_complete) * + sizeof(struct tx_result)); + + wl1251_mem_write(wl, + wl->data_path->tx_complete_addr, + result, + (num_complete - + FW_TX_CMPLT_BLOCK_SIZE + + wl->next_tx_complete) * + sizeof(struct tx_result)); + + } else { + /* We have to write the whole array */ + wl1251_mem_write(wl, + wl->data_path->tx_complete_addr, + result, + FW_TX_CMPLT_BLOCK_SIZE * + sizeof(struct tx_result)); + } + + } + + wl->next_tx_complete = result_index; +} + +/* caller must hold wl->mutex */ +void wl1251_tx_flush(struct wl1251 *wl) +{ + int i; + struct sk_buff *skb; + struct ieee80211_tx_info *info; + + /* TX failure */ +/* control->flags = 0; FIXME */ + + while ((skb = skb_dequeue(&wl->tx_queue))) { + info = IEEE80211_SKB_CB(skb); + + wl1251_debug(DEBUG_TX, "flushing skb 0x%p", skb); + + if (!(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS)) + continue; + + ieee80211_tx_status(wl->hw, skb); + } + + for (i = 0; i < FW_TX_CMPLT_BLOCK_SIZE; i++) + if (wl->tx_frames[i] != NULL) { + skb = wl->tx_frames[i]; + info = IEEE80211_SKB_CB(skb); + + if (!(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS)) + continue; + + ieee80211_tx_status(wl->hw, skb); + wl->tx_frames[i] = NULL; + } +} |