Merge branch 'for-2.6.39' of git://linux-nfs.org/~bfields/linux
[pandora-kernel.git] / drivers / net / wireless / wl12xx / rx.c
1 /*
2  * This file is part of wl1271
3  *
4  * Copyright (C) 2009 Nokia Corporation
5  *
6  * Contact: Luciano Coelho <luciano.coelho@nokia.com>
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License
10  * version 2 as published by the Free Software Foundation.
11  *
12  * This program is distributed in the hope that it will be useful, but
13  * WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
20  * 02110-1301 USA
21  *
22  */
23
24 #include <linux/gfp.h>
25
26 #include "wl12xx.h"
27 #include "acx.h"
28 #include "reg.h"
29 #include "rx.h"
30 #include "io.h"
31
32 static u8 wl1271_rx_get_mem_block(struct wl1271_fw_common_status *status,
33                                   u32 drv_rx_counter)
34 {
35         return le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]) &
36                 RX_MEM_BLOCK_MASK;
37 }
38
39 static u32 wl1271_rx_get_buf_size(struct wl1271_fw_common_status *status,
40                                  u32 drv_rx_counter)
41 {
42         return (le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]) &
43                 RX_BUF_SIZE_MASK) >> RX_BUF_SIZE_SHIFT_DIV;
44 }
45
46 static void wl1271_rx_status(struct wl1271 *wl,
47                              struct wl1271_rx_descriptor *desc,
48                              struct ieee80211_rx_status *status,
49                              u8 beacon)
50 {
51         enum ieee80211_band desc_band;
52
53         memset(status, 0, sizeof(struct ieee80211_rx_status));
54
55         status->band = wl->band;
56
57         if ((desc->flags & WL1271_RX_DESC_BAND_MASK) == WL1271_RX_DESC_BAND_BG)
58                 desc_band = IEEE80211_BAND_2GHZ;
59         else
60                 desc_band = IEEE80211_BAND_5GHZ;
61
62         status->rate_idx = wl1271_rate_to_idx(desc->rate, desc_band);
63
64 #ifdef CONFIG_WL12XX_HT
65         /* 11n support */
66         if (desc->rate <= CONF_HW_RXTX_RATE_MCS0)
67                 status->flag |= RX_FLAG_HT;
68 #endif
69
70         status->signal = desc->rssi;
71
72         /*
73          * FIXME: In wl1251, the SNR should be divided by two.  In wl1271 we
74          * need to divide by two for now, but TI has been discussing about
75          * changing it.  This needs to be rechecked.
76          */
77         wl->noise = desc->rssi - (desc->snr >> 1);
78
79         status->freq = ieee80211_channel_to_frequency(desc->channel, desc_band);
80
81         if (desc->flags & WL1271_RX_DESC_ENCRYPT_MASK) {
82                 status->flag |= RX_FLAG_IV_STRIPPED | RX_FLAG_MMIC_STRIPPED;
83
84                 if (likely(!(desc->status & WL1271_RX_DESC_DECRYPT_FAIL)))
85                         status->flag |= RX_FLAG_DECRYPTED;
86                 if (unlikely(desc->status & WL1271_RX_DESC_MIC_FAIL))
87                         status->flag |= RX_FLAG_MMIC_ERROR;
88         }
89 }
90
91 static int wl1271_rx_handle_data(struct wl1271 *wl, u8 *data, u32 length)
92 {
93         struct wl1271_rx_descriptor *desc;
94         struct sk_buff *skb;
95         struct ieee80211_hdr *hdr;
96         u8 *buf;
97         u8 beacon = 0;
98
99         /*
100          * In PLT mode we seem to get frames and mac80211 warns about them,
101          * workaround this by not retrieving them at all.
102          */
103         if (unlikely(wl->state == WL1271_STATE_PLT))
104                 return -EINVAL;
105
106         skb = __dev_alloc_skb(length, GFP_KERNEL);
107         if (!skb) {
108                 wl1271_error("Couldn't allocate RX frame");
109                 return -ENOMEM;
110         }
111
112         buf = skb_put(skb, length);
113         memcpy(buf, data, length);
114
115         /* the data read starts with the descriptor */
116         desc = (struct wl1271_rx_descriptor *) buf;
117
118         /* now we pull the descriptor out of the buffer */
119         skb_pull(skb, sizeof(*desc));
120
121         hdr = (struct ieee80211_hdr *)skb->data;
122         if (ieee80211_is_beacon(hdr->frame_control))
123                 beacon = 1;
124
125         wl1271_rx_status(wl, desc, IEEE80211_SKB_RXCB(skb), beacon);
126
127         wl1271_debug(DEBUG_RX, "rx skb 0x%p: %d B %s", skb, skb->len,
128                      beacon ? "beacon" : "");
129
130         skb_trim(skb, skb->len - desc->pad_len);
131
132         skb_queue_tail(&wl->deferred_rx_queue, skb);
133         ieee80211_queue_work(wl->hw, &wl->netstack_work);
134
135         return 0;
136 }
137
138 void wl1271_rx(struct wl1271 *wl, struct wl1271_fw_common_status *status)
139 {
140         struct wl1271_acx_mem_map *wl_mem_map = wl->target_mem_map;
141         u32 buf_size;
142         u32 fw_rx_counter  = status->fw_rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
143         u32 drv_rx_counter = wl->rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
144         u32 rx_counter;
145         u32 mem_block;
146         u32 pkt_length;
147         u32 pkt_offset;
148
149         while (drv_rx_counter != fw_rx_counter) {
150                 buf_size = 0;
151                 rx_counter = drv_rx_counter;
152                 while (rx_counter != fw_rx_counter) {
153                         pkt_length = wl1271_rx_get_buf_size(status, rx_counter);
154                         if (buf_size + pkt_length > WL1271_AGGR_BUFFER_SIZE)
155                                 break;
156                         buf_size += pkt_length;
157                         rx_counter++;
158                         rx_counter &= NUM_RX_PKT_DESC_MOD_MASK;
159                 }
160
161                 if (buf_size == 0) {
162                         wl1271_warning("received empty data");
163                         break;
164                 }
165
166                 /*
167                  * Choose the block we want to read
168                  * For aggregated packets, only the first memory block should
169                  * be retrieved. The FW takes care of the rest.
170                  */
171                 mem_block = wl1271_rx_get_mem_block(status, drv_rx_counter);
172                 wl->rx_mem_pool_addr.addr = (mem_block << 8) +
173                         le32_to_cpu(wl_mem_map->packet_memory_pool_start);
174                 wl->rx_mem_pool_addr.addr_extra =
175                         wl->rx_mem_pool_addr.addr + 4;
176                 wl1271_write(wl, WL1271_SLV_REG_DATA, &wl->rx_mem_pool_addr,
177                                 sizeof(wl->rx_mem_pool_addr), false);
178
179                 /* Read all available packets at once */
180                 wl1271_read(wl, WL1271_SLV_MEM_DATA, wl->aggr_buf,
181                                 buf_size, true);
182
183                 /* Split data into separate packets */
184                 pkt_offset = 0;
185                 while (pkt_offset < buf_size) {
186                         pkt_length = wl1271_rx_get_buf_size(status,
187                                         drv_rx_counter);
188                         /*
189                          * the handle data call can only fail in memory-outage
190                          * conditions, in that case the received frame will just
191                          * be dropped.
192                          */
193                         wl1271_rx_handle_data(wl,
194                                               wl->aggr_buf + pkt_offset,
195                                               pkt_length);
196                         wl->rx_counter++;
197                         drv_rx_counter++;
198                         drv_rx_counter &= NUM_RX_PKT_DESC_MOD_MASK;
199                         pkt_offset += pkt_length;
200                 }
201         }
202
203         /*
204          * Write the driver's packet counter to the FW. This is only required
205          * for older hardware revisions
206          */
207         if (wl->quirks & WL12XX_QUIRK_END_OF_TRANSACTION)
208                 wl1271_write32(wl, RX_DRIVER_COUNTER_ADDRESS, wl->rx_counter);
209 }
210
211 void wl1271_set_default_filters(struct wl1271 *wl)
212 {
213         if (wl->bss_type == BSS_TYPE_AP_BSS) {
214                 wl->rx_config = WL1271_DEFAULT_AP_RX_CONFIG;
215                 wl->rx_filter = WL1271_DEFAULT_AP_RX_FILTER;
216         } else {
217                 wl->rx_config = WL1271_DEFAULT_STA_RX_CONFIG;
218                 wl->rx_filter = WL1271_DEFAULT_STA_RX_FILTER;
219         }
220 }