Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
[cascardo/linux.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 #include <linux/sched.h>
26
27 #include "wl12xx.h"
28 #include "acx.h"
29 #include "reg.h"
30 #include "rx.h"
31 #include "io.h"
32
33 static u8 wl12xx_rx_get_mem_block(struct wl12xx_fw_status *status,
34                                   u32 drv_rx_counter)
35 {
36         return le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]) &
37                 RX_MEM_BLOCK_MASK;
38 }
39
40 static u32 wl12xx_rx_get_buf_size(struct wl12xx_fw_status *status,
41                                  u32 drv_rx_counter)
42 {
43         return (le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]) &
44                 RX_BUF_SIZE_MASK) >> RX_BUF_SIZE_SHIFT_DIV;
45 }
46
47 static bool wl12xx_rx_get_unaligned(struct wl12xx_fw_status *status,
48                                     u32 drv_rx_counter)
49 {
50         /* Convert the value to bool */
51         return !!(le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]) &
52                 RX_BUF_UNALIGNED_PAYLOAD);
53 }
54
55 static void wl1271_rx_status(struct wl1271 *wl,
56                              struct wl1271_rx_descriptor *desc,
57                              struct ieee80211_rx_status *status,
58                              u8 beacon)
59 {
60         memset(status, 0, sizeof(struct ieee80211_rx_status));
61
62         if ((desc->flags & WL1271_RX_DESC_BAND_MASK) == WL1271_RX_DESC_BAND_BG)
63                 status->band = IEEE80211_BAND_2GHZ;
64         else
65                 status->band = IEEE80211_BAND_5GHZ;
66
67         status->rate_idx = wl1271_rate_to_idx(desc->rate, status->band);
68
69         /* 11n support */
70         if (desc->rate <= CONF_HW_RXTX_RATE_MCS0)
71                 status->flag |= RX_FLAG_HT;
72
73         status->signal = desc->rssi;
74
75         /*
76          * FIXME: In wl1251, the SNR should be divided by two.  In wl1271 we
77          * need to divide by two for now, but TI has been discussing about
78          * changing it.  This needs to be rechecked.
79          */
80         wl->noise = desc->rssi - (desc->snr >> 1);
81
82         status->freq = ieee80211_channel_to_frequency(desc->channel,
83                                                       status->band);
84
85         if (desc->flags & WL1271_RX_DESC_ENCRYPT_MASK) {
86                 u8 desc_err_code = desc->status & WL1271_RX_DESC_STATUS_MASK;
87
88                 status->flag |= RX_FLAG_IV_STRIPPED | RX_FLAG_MMIC_STRIPPED |
89                                 RX_FLAG_DECRYPTED;
90
91                 if (unlikely(desc_err_code == WL1271_RX_DESC_MIC_FAIL)) {
92                         status->flag |= RX_FLAG_MMIC_ERROR;
93                         wl1271_warning("Michael MIC error");
94                 }
95         }
96 }
97
98 static int wl1271_rx_handle_data(struct wl1271 *wl, u8 *data, u32 length,
99                                  bool unaligned)
100 {
101         struct wl1271_rx_descriptor *desc;
102         struct sk_buff *skb;
103         struct ieee80211_hdr *hdr;
104         u8 *buf;
105         u8 beacon = 0;
106         u8 is_data = 0;
107         u8 reserved = unaligned ? NET_IP_ALIGN : 0;
108         u16 seq_num;
109
110         /*
111          * In PLT mode we seem to get frames and mac80211 warns about them,
112          * workaround this by not retrieving them at all.
113          */
114         if (unlikely(wl->state == WL1271_STATE_PLT))
115                 return -EINVAL;
116
117         /* the data read starts with the descriptor */
118         desc = (struct wl1271_rx_descriptor *) data;
119
120         if (desc->packet_class == WL12XX_RX_CLASS_LOGGER) {
121                 size_t len = length - sizeof(*desc);
122                 wl12xx_copy_fwlog(wl, data + sizeof(*desc), len);
123                 wake_up_interruptible(&wl->fwlog_waitq);
124                 return 0;
125         }
126
127         switch (desc->status & WL1271_RX_DESC_STATUS_MASK) {
128         /* discard corrupted packets */
129         case WL1271_RX_DESC_DRIVER_RX_Q_FAIL:
130         case WL1271_RX_DESC_DECRYPT_FAIL:
131                 wl1271_warning("corrupted packet in RX with status: 0x%x",
132                                desc->status & WL1271_RX_DESC_STATUS_MASK);
133                 return -EINVAL;
134         case WL1271_RX_DESC_SUCCESS:
135         case WL1271_RX_DESC_MIC_FAIL:
136                 break;
137         default:
138                 wl1271_error("invalid RX descriptor status: 0x%x",
139                              desc->status & WL1271_RX_DESC_STATUS_MASK);
140                 return -EINVAL;
141         }
142
143         /* skb length not included rx descriptor */
144         skb = __dev_alloc_skb(length + reserved - sizeof(*desc), GFP_KERNEL);
145         if (!skb) {
146                 wl1271_error("Couldn't allocate RX frame");
147                 return -ENOMEM;
148         }
149
150         /* reserve the unaligned payload(if any) */
151         skb_reserve(skb, reserved);
152
153         buf = skb_put(skb, length - sizeof(*desc));
154
155         /*
156          * Copy packets from aggregation buffer to the skbs without rx
157          * descriptor and with packet payload aligned care. In case of unaligned
158          * packets copy the packets in offset of 2 bytes guarantee IP header
159          * payload aligned to 4 bytes.
160          */
161         memcpy(buf, data + sizeof(*desc), length - sizeof(*desc));
162
163         hdr = (struct ieee80211_hdr *)skb->data;
164         if (ieee80211_is_beacon(hdr->frame_control))
165                 beacon = 1;
166         if (ieee80211_is_data_present(hdr->frame_control))
167                 is_data = 1;
168
169         wl1271_rx_status(wl, desc, IEEE80211_SKB_RXCB(skb), beacon);
170
171         seq_num = (le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_SEQ) >> 4;
172         wl1271_debug(DEBUG_RX, "rx skb 0x%p: %d B %s seq %d", skb,
173                      skb->len - desc->pad_len,
174                      beacon ? "beacon" : "",
175                      seq_num);
176
177         skb_trim(skb, skb->len - desc->pad_len);
178
179         skb_queue_tail(&wl->deferred_rx_queue, skb);
180         queue_work(wl->freezable_wq, &wl->netstack_work);
181
182         return is_data;
183 }
184
185 void wl12xx_rx(struct wl1271 *wl, struct wl12xx_fw_status *status)
186 {
187         struct wl1271_acx_mem_map *wl_mem_map = wl->target_mem_map;
188         u32 buf_size;
189         u32 fw_rx_counter  = status->fw_rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
190         u32 drv_rx_counter = wl->rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
191         u32 rx_counter;
192         u32 mem_block;
193         u32 pkt_length;
194         u32 pkt_offset;
195         bool is_ap = (wl->bss_type == BSS_TYPE_AP_BSS);
196         bool had_data = false;
197         bool unaligned = false;
198
199         while (drv_rx_counter != fw_rx_counter) {
200                 buf_size = 0;
201                 rx_counter = drv_rx_counter;
202                 while (rx_counter != fw_rx_counter) {
203                         pkt_length = wl12xx_rx_get_buf_size(status, rx_counter);
204                         if (buf_size + pkt_length > WL1271_AGGR_BUFFER_SIZE)
205                                 break;
206                         buf_size += pkt_length;
207                         rx_counter++;
208                         rx_counter &= NUM_RX_PKT_DESC_MOD_MASK;
209                 }
210
211                 if (buf_size == 0) {
212                         wl1271_warning("received empty data");
213                         break;
214                 }
215
216                 if (wl->chip.id != CHIP_ID_1283_PG20) {
217                         /*
218                          * Choose the block we want to read
219                          * For aggregated packets, only the first memory block
220                          * should be retrieved. The FW takes care of the rest.
221                          */
222                         mem_block = wl12xx_rx_get_mem_block(status,
223                                                             drv_rx_counter);
224
225                         wl->rx_mem_pool_addr.addr = (mem_block << 8) +
226                            le32_to_cpu(wl_mem_map->packet_memory_pool_start);
227
228                         wl->rx_mem_pool_addr.addr_extra =
229                                 wl->rx_mem_pool_addr.addr + 4;
230
231                         wl1271_write(wl, WL1271_SLV_REG_DATA,
232                                      &wl->rx_mem_pool_addr,
233                                      sizeof(wl->rx_mem_pool_addr), false);
234                 }
235
236                 /* Read all available packets at once */
237                 wl1271_read(wl, WL1271_SLV_MEM_DATA, wl->aggr_buf,
238                                 buf_size, true);
239
240                 /* Split data into separate packets */
241                 pkt_offset = 0;
242                 while (pkt_offset < buf_size) {
243                         pkt_length = wl12xx_rx_get_buf_size(status,
244                                         drv_rx_counter);
245
246                         unaligned = wl12xx_rx_get_unaligned(status,
247                                         drv_rx_counter);
248
249                         /*
250                          * the handle data call can only fail in memory-outage
251                          * conditions, in that case the received frame will just
252                          * be dropped.
253                          */
254                         if (wl1271_rx_handle_data(wl,
255                                                   wl->aggr_buf + pkt_offset,
256                                                   pkt_length, unaligned) == 1)
257                                 had_data = true;
258
259                         wl->rx_counter++;
260                         drv_rx_counter++;
261                         drv_rx_counter &= NUM_RX_PKT_DESC_MOD_MASK;
262                         pkt_offset += pkt_length;
263                 }
264         }
265
266         /*
267          * Write the driver's packet counter to the FW. This is only required
268          * for older hardware revisions
269          */
270         if (wl->quirks & WL12XX_QUIRK_END_OF_TRANSACTION)
271                 wl1271_write32(wl, RX_DRIVER_COUNTER_ADDRESS, wl->rx_counter);
272
273         if (!is_ap && wl->conf.rx_streaming.interval && had_data &&
274             (wl->conf.rx_streaming.always ||
275              test_bit(WL1271_FLAG_SOFT_GEMINI, &wl->flags))) {
276                 u32 timeout = wl->conf.rx_streaming.duration;
277
278                 /* restart rx streaming */
279                 if (!test_bit(WL1271_FLAG_RX_STREAMING_STARTED, &wl->flags))
280                         ieee80211_queue_work(wl->hw,
281                                              &wl->rx_streaming_enable_work);
282
283                 mod_timer(&wl->rx_streaming_timer,
284                           jiffies + msecs_to_jiffies(timeout));
285         }
286 }