Linux-libre 3.5.4-gnu1
[librecmc/linux-libre.git] / drivers / net / wireless / ti / wlcore / 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 "wlcore.h"
28 #include "debug.h"
29 #include "acx.h"
30 #include "rx.h"
31 #include "tx.h"
32 #include "io.h"
33 #include "hw_ops.h"
34
35 /*
36  * TODO: this is here just for now, it must be removed when the data
37  * operations are in place.
38  */
39 #include "../wl12xx/reg.h"
40
41 static u32 wlcore_rx_get_buf_size(struct wl1271 *wl,
42                                   u32 rx_pkt_desc)
43 {
44         if (wl->quirks & WLCORE_QUIRK_RX_BLOCKSIZE_ALIGN)
45                 return (rx_pkt_desc & ALIGNED_RX_BUF_SIZE_MASK) >>
46                        ALIGNED_RX_BUF_SIZE_SHIFT;
47
48         return (rx_pkt_desc & RX_BUF_SIZE_MASK) >> RX_BUF_SIZE_SHIFT_DIV;
49 }
50
51 static u32 wlcore_rx_get_align_buf_size(struct wl1271 *wl, u32 pkt_len)
52 {
53         if (wl->quirks & WLCORE_QUIRK_RX_BLOCKSIZE_ALIGN)
54                 return ALIGN(pkt_len, WL12XX_BUS_BLOCK_SIZE);
55
56         return pkt_len;
57 }
58
59 static void wl1271_rx_status(struct wl1271 *wl,
60                              struct wl1271_rx_descriptor *desc,
61                              struct ieee80211_rx_status *status,
62                              u8 beacon)
63 {
64         memset(status, 0, sizeof(struct ieee80211_rx_status));
65
66         if ((desc->flags & WL1271_RX_DESC_BAND_MASK) == WL1271_RX_DESC_BAND_BG)
67                 status->band = IEEE80211_BAND_2GHZ;
68         else
69                 status->band = IEEE80211_BAND_5GHZ;
70
71         status->rate_idx = wlcore_rate_to_idx(wl, desc->rate, status->band);
72
73         /* 11n support */
74         if (desc->rate <= wl->hw_min_ht_rate)
75                 status->flag |= RX_FLAG_HT;
76
77         status->signal = desc->rssi;
78
79         /*
80          * FIXME: In wl1251, the SNR should be divided by two.  In wl1271 we
81          * need to divide by two for now, but TI has been discussing about
82          * changing it.  This needs to be rechecked.
83          */
84         wl->noise = desc->rssi - (desc->snr >> 1);
85
86         status->freq = ieee80211_channel_to_frequency(desc->channel,
87                                                       status->band);
88
89         if (desc->flags & WL1271_RX_DESC_ENCRYPT_MASK) {
90                 u8 desc_err_code = desc->status & WL1271_RX_DESC_STATUS_MASK;
91
92                 status->flag |= RX_FLAG_IV_STRIPPED | RX_FLAG_MMIC_STRIPPED |
93                                 RX_FLAG_DECRYPTED;
94
95                 if (unlikely(desc_err_code == WL1271_RX_DESC_MIC_FAIL)) {
96                         status->flag |= RX_FLAG_MMIC_ERROR;
97                         wl1271_warning("Michael MIC error");
98                 }
99         }
100 }
101
102 static int wl1271_rx_handle_data(struct wl1271 *wl, u8 *data, u32 length,
103                                  enum wl_rx_buf_align rx_align, u8 *hlid)
104 {
105         struct wl1271_rx_descriptor *desc;
106         struct sk_buff *skb;
107         struct ieee80211_hdr *hdr;
108         u8 *buf;
109         u8 beacon = 0;
110         u8 is_data = 0;
111         u8 reserved = 0;
112         u16 seq_num;
113         u32 pkt_data_len;
114
115         /*
116          * In PLT mode we seem to get frames and mac80211 warns about them,
117          * workaround this by not retrieving them at all.
118          */
119         if (unlikely(wl->plt))
120                 return -EINVAL;
121
122         pkt_data_len = wlcore_hw_get_rx_packet_len(wl, data, length);
123         if (!pkt_data_len) {
124                 wl1271_error("Invalid packet arrived from HW. length %d",
125                              length);
126                 return -EINVAL;
127         }
128
129         if (rx_align == WLCORE_RX_BUF_UNALIGNED)
130                 reserved = NET_IP_ALIGN;
131
132         /* the data read starts with the descriptor */
133         desc = (struct wl1271_rx_descriptor *) data;
134
135         if (desc->packet_class == WL12XX_RX_CLASS_LOGGER) {
136                 size_t len = length - sizeof(*desc);
137                 wl12xx_copy_fwlog(wl, data + sizeof(*desc), len);
138                 wake_up_interruptible(&wl->fwlog_waitq);
139                 return 0;
140         }
141
142         switch (desc->status & WL1271_RX_DESC_STATUS_MASK) {
143         /* discard corrupted packets */
144         case WL1271_RX_DESC_DRIVER_RX_Q_FAIL:
145         case WL1271_RX_DESC_DECRYPT_FAIL:
146                 wl1271_warning("corrupted packet in RX with status: 0x%x",
147                                desc->status & WL1271_RX_DESC_STATUS_MASK);
148                 return -EINVAL;
149         case WL1271_RX_DESC_SUCCESS:
150         case WL1271_RX_DESC_MIC_FAIL:
151                 break;
152         default:
153                 wl1271_error("invalid RX descriptor status: 0x%x",
154                              desc->status & WL1271_RX_DESC_STATUS_MASK);
155                 return -EINVAL;
156         }
157
158         /* skb length not including rx descriptor */
159         skb = __dev_alloc_skb(pkt_data_len + reserved, GFP_KERNEL);
160         if (!skb) {
161                 wl1271_error("Couldn't allocate RX frame");
162                 return -ENOMEM;
163         }
164
165         /* reserve the unaligned payload(if any) */
166         skb_reserve(skb, reserved);
167
168         buf = skb_put(skb, pkt_data_len);
169
170         /*
171          * Copy packets from aggregation buffer to the skbs without rx
172          * descriptor and with packet payload aligned care. In case of unaligned
173          * packets copy the packets in offset of 2 bytes guarantee IP header
174          * payload aligned to 4 bytes.
175          */
176         memcpy(buf, data + sizeof(*desc), pkt_data_len);
177         if (rx_align == WLCORE_RX_BUF_PADDED)
178                 skb_pull(skb, NET_IP_ALIGN);
179
180         *hlid = desc->hlid;
181
182         hdr = (struct ieee80211_hdr *)skb->data;
183         if (ieee80211_is_beacon(hdr->frame_control))
184                 beacon = 1;
185         if (ieee80211_is_data_present(hdr->frame_control))
186                 is_data = 1;
187
188         wl1271_rx_status(wl, desc, IEEE80211_SKB_RXCB(skb), beacon);
189
190         seq_num = (le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_SEQ) >> 4;
191         wl1271_debug(DEBUG_RX, "rx skb 0x%p: %d B %s seq %d hlid %d", skb,
192                      skb->len - desc->pad_len,
193                      beacon ? "beacon" : "",
194                      seq_num, *hlid);
195
196         skb_queue_tail(&wl->deferred_rx_queue, skb);
197         queue_work(wl->freezable_wq, &wl->netstack_work);
198
199         return is_data;
200 }
201
202 void wl12xx_rx(struct wl1271 *wl, struct wl_fw_status *status)
203 {
204         unsigned long active_hlids[BITS_TO_LONGS(WL12XX_MAX_LINKS)] = {0};
205         u32 buf_size;
206         u32 fw_rx_counter  = status->fw_rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
207         u32 drv_rx_counter = wl->rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
208         u32 rx_counter;
209         u32 pkt_len, align_pkt_len;
210         u32 pkt_offset, des;
211         u8 hlid;
212         enum wl_rx_buf_align rx_align;
213
214         while (drv_rx_counter != fw_rx_counter) {
215                 buf_size = 0;
216                 rx_counter = drv_rx_counter;
217                 while (rx_counter != fw_rx_counter) {
218                         des = le32_to_cpu(status->rx_pkt_descs[rx_counter]);
219                         pkt_len = wlcore_rx_get_buf_size(wl, des);
220                         align_pkt_len = wlcore_rx_get_align_buf_size(wl,
221                                                                      pkt_len);
222                         if (buf_size + align_pkt_len > WL1271_AGGR_BUFFER_SIZE)
223                                 break;
224                         buf_size += align_pkt_len;
225                         rx_counter++;
226                         rx_counter &= NUM_RX_PKT_DESC_MOD_MASK;
227                 }
228
229                 if (buf_size == 0) {
230                         wl1271_warning("received empty data");
231                         break;
232                 }
233
234                 /* Read all available packets at once */
235                 des = le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]);
236                 wlcore_hw_prepare_read(wl, des, buf_size);
237                 wlcore_read_data(wl, REG_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                         des = le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]);
244                         pkt_len = wlcore_rx_get_buf_size(wl, des);
245                         rx_align = wlcore_hw_get_rx_buf_align(wl, des);
246
247                         /*
248                          * the handle data call can only fail in memory-outage
249                          * conditions, in that case the received frame will just
250                          * be dropped.
251                          */
252                         if (wl1271_rx_handle_data(wl,
253                                                   wl->aggr_buf + pkt_offset,
254                                                   pkt_len, rx_align,
255                                                   &hlid) == 1) {
256                                 if (hlid < WL12XX_MAX_LINKS)
257                                         __set_bit(hlid, active_hlids);
258                                 else
259                                         WARN(1,
260                                              "hlid exceeded WL12XX_MAX_LINKS "
261                                              "(%d)\n", hlid);
262                         }
263
264                         wl->rx_counter++;
265                         drv_rx_counter++;
266                         drv_rx_counter &= NUM_RX_PKT_DESC_MOD_MASK;
267                         pkt_offset += wlcore_rx_get_align_buf_size(wl, pkt_len);
268                 }
269         }
270
271         /*
272          * Write the driver's packet counter to the FW. This is only required
273          * for older hardware revisions
274          */
275         if (wl->quirks & WLCORE_QUIRK_END_OF_TRANSACTION)
276                 wl1271_write32(wl, WL12XX_REG_RX_DRIVER_COUNTER,
277                                wl->rx_counter);
278
279         wl12xx_rearm_rx_streaming(wl, active_hlids);
280 }
281
282 #ifdef CONFIG_PM
283 int wl1271_rx_filter_enable(struct wl1271 *wl,
284                             int index, bool enable,
285                             struct wl12xx_rx_filter *filter)
286 {
287         int ret;
288
289         if (wl->rx_filter_enabled[index] == enable) {
290                 wl1271_warning("Request to enable an already "
291                              "enabled rx filter %d", index);
292                 return 0;
293         }
294
295         ret = wl1271_acx_set_rx_filter(wl, index, enable, filter);
296
297         if (ret) {
298                 wl1271_error("Failed to %s rx data filter %d (err=%d)",
299                              enable ? "enable" : "disable", index, ret);
300                 return ret;
301         }
302
303         wl->rx_filter_enabled[index] = enable;
304
305         return 0;
306 }
307
308 void wl1271_rx_filter_clear_all(struct wl1271 *wl)
309 {
310         int i;
311
312         for (i = 0; i < WL1271_MAX_RX_FILTERS; i++) {
313                 if (!wl->rx_filter_enabled[i])
314                         continue;
315                 wl1271_rx_filter_enable(wl, i, 0, NULL);
316         }
317 }
318 #endif /* CONFIG_PM */