xref: /linux/drivers/net/wireless/ti/wlcore/rx.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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 	/*
78 	* Read the signal level and antenna diversity indication.
79 	* The msb in the signal level is always set as it is a
80 	* negative number.
81 	* The antenna indication is the msb of the rssi.
82 	*/
83 	status->signal = ((desc->rssi & RSSI_LEVEL_BITMASK) | BIT(7));
84 	status->antenna = ((desc->rssi & ANT_DIVERSITY_BITMASK) >> 7);
85 
86 	/*
87 	 * FIXME: In wl1251, the SNR should be divided by two.  In wl1271 we
88 	 * need to divide by two for now, but TI has been discussing about
89 	 * changing it.  This needs to be rechecked.
90 	 */
91 	wl->noise = desc->rssi - (desc->snr >> 1);
92 
93 	status->freq = ieee80211_channel_to_frequency(desc->channel,
94 						      status->band);
95 
96 	if (desc->flags & WL1271_RX_DESC_ENCRYPT_MASK) {
97 		u8 desc_err_code = desc->status & WL1271_RX_DESC_STATUS_MASK;
98 
99 		status->flag |= RX_FLAG_IV_STRIPPED | RX_FLAG_MMIC_STRIPPED |
100 				RX_FLAG_DECRYPTED;
101 
102 		if (unlikely(desc_err_code & WL1271_RX_DESC_MIC_FAIL)) {
103 			status->flag |= RX_FLAG_MMIC_ERROR;
104 			wl1271_warning("Michael MIC error. Desc: 0x%x",
105 				       desc_err_code);
106 		}
107 	}
108 
109 	if (beacon)
110 		wlcore_set_pending_regdomain_ch(wl, (u16)desc->channel,
111 						status->band);
112 }
113 
114 static int wl1271_rx_handle_data(struct wl1271 *wl, u8 *data, u32 length,
115 				 enum wl_rx_buf_align rx_align, u8 *hlid)
116 {
117 	struct wl1271_rx_descriptor *desc;
118 	struct sk_buff *skb;
119 	struct ieee80211_hdr *hdr;
120 	u8 *buf;
121 	u8 beacon = 0;
122 	u8 is_data = 0;
123 	u8 reserved = 0, offset_to_data = 0;
124 	u16 seq_num;
125 	u32 pkt_data_len;
126 
127 	/*
128 	 * In PLT mode we seem to get frames and mac80211 warns about them,
129 	 * workaround this by not retrieving them at all.
130 	 */
131 	if (unlikely(wl->plt))
132 		return -EINVAL;
133 
134 	pkt_data_len = wlcore_hw_get_rx_packet_len(wl, data, length);
135 	if (!pkt_data_len) {
136 		wl1271_error("Invalid packet arrived from HW. length %d",
137 			     length);
138 		return -EINVAL;
139 	}
140 
141 	if (rx_align == WLCORE_RX_BUF_UNALIGNED)
142 		reserved = RX_BUF_ALIGN;
143 	else if (rx_align == WLCORE_RX_BUF_PADDED)
144 		offset_to_data = RX_BUF_ALIGN;
145 
146 	/* the data read starts with the descriptor */
147 	desc = (struct wl1271_rx_descriptor *) data;
148 
149 	if (desc->packet_class == WL12XX_RX_CLASS_LOGGER) {
150 		size_t len = length - sizeof(*desc);
151 		wl12xx_copy_fwlog(wl, data + sizeof(*desc), len);
152 		wake_up_interruptible(&wl->fwlog_waitq);
153 		return 0;
154 	}
155 
156 	/* discard corrupted packets */
157 	if (desc->status & WL1271_RX_DESC_DECRYPT_FAIL) {
158 		hdr = (void *)(data + sizeof(*desc) + offset_to_data);
159 		wl1271_warning("corrupted packet in RX: status: 0x%x len: %d",
160 			       desc->status & WL1271_RX_DESC_STATUS_MASK,
161 			       pkt_data_len);
162 		wl1271_dump((DEBUG_RX|DEBUG_CMD), "PKT: ", data + sizeof(*desc),
163 			    min(pkt_data_len,
164 				ieee80211_hdrlen(hdr->frame_control)));
165 		return -EINVAL;
166 	}
167 
168 	/* skb length not including rx descriptor */
169 	skb = __dev_alloc_skb(pkt_data_len + reserved, GFP_KERNEL);
170 	if (!skb) {
171 		wl1271_error("Couldn't allocate RX frame");
172 		return -ENOMEM;
173 	}
174 
175 	/* reserve the unaligned payload(if any) */
176 	skb_reserve(skb, reserved);
177 
178 	buf = skb_put(skb, pkt_data_len);
179 
180 	/*
181 	 * Copy packets from aggregation buffer to the skbs without rx
182 	 * descriptor and with packet payload aligned care. In case of unaligned
183 	 * packets copy the packets in offset of 2 bytes guarantee IP header
184 	 * payload aligned to 4 bytes.
185 	 */
186 	memcpy(buf, data + sizeof(*desc), pkt_data_len);
187 	if (rx_align == WLCORE_RX_BUF_PADDED)
188 		skb_pull(skb, RX_BUF_ALIGN);
189 
190 	*hlid = desc->hlid;
191 
192 	hdr = (struct ieee80211_hdr *)skb->data;
193 	if (ieee80211_is_beacon(hdr->frame_control))
194 		beacon = 1;
195 	if (ieee80211_is_data_present(hdr->frame_control))
196 		is_data = 1;
197 
198 	wl1271_rx_status(wl, desc, IEEE80211_SKB_RXCB(skb), beacon);
199 	wlcore_hw_set_rx_csum(wl, desc, skb);
200 
201 	seq_num = (le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_SEQ) >> 4;
202 	wl1271_debug(DEBUG_RX, "rx skb 0x%p: %d B %s seq %d hlid %d", skb,
203 		     skb->len - desc->pad_len,
204 		     beacon ? "beacon" : "",
205 		     seq_num, *hlid);
206 
207 	skb_queue_tail(&wl->deferred_rx_queue, skb);
208 	queue_work(wl->freezable_wq, &wl->netstack_work);
209 
210 	return is_data;
211 }
212 
213 int wlcore_rx(struct wl1271 *wl, struct wl_fw_status *status)
214 {
215 	unsigned long active_hlids[BITS_TO_LONGS(WLCORE_MAX_LINKS)] = {0};
216 	u32 buf_size;
217 	u32 fw_rx_counter = status->fw_rx_counter % wl->num_rx_desc;
218 	u32 drv_rx_counter = wl->rx_counter % wl->num_rx_desc;
219 	u32 rx_counter;
220 	u32 pkt_len, align_pkt_len;
221 	u32 pkt_offset, des;
222 	u8 hlid;
223 	enum wl_rx_buf_align rx_align;
224 	int ret = 0;
225 
226 	while (drv_rx_counter != fw_rx_counter) {
227 		buf_size = 0;
228 		rx_counter = drv_rx_counter;
229 		while (rx_counter != fw_rx_counter) {
230 			des = le32_to_cpu(status->rx_pkt_descs[rx_counter]);
231 			pkt_len = wlcore_rx_get_buf_size(wl, des);
232 			align_pkt_len = wlcore_rx_get_align_buf_size(wl,
233 								     pkt_len);
234 			if (buf_size + align_pkt_len > wl->aggr_buf_size)
235 				break;
236 			buf_size += align_pkt_len;
237 			rx_counter++;
238 			rx_counter %= wl->num_rx_desc;
239 		}
240 
241 		if (buf_size == 0) {
242 			wl1271_warning("received empty data");
243 			break;
244 		}
245 
246 		/* Read all available packets at once */
247 		des = le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]);
248 		ret = wlcore_hw_prepare_read(wl, des, buf_size);
249 		if (ret < 0)
250 			goto out;
251 
252 		ret = wlcore_read_data(wl, REG_SLV_MEM_DATA, wl->aggr_buf,
253 				       buf_size, true);
254 		if (ret < 0)
255 			goto out;
256 
257 		/* Split data into separate packets */
258 		pkt_offset = 0;
259 		while (pkt_offset < buf_size) {
260 			des = le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]);
261 			pkt_len = wlcore_rx_get_buf_size(wl, des);
262 			rx_align = wlcore_hw_get_rx_buf_align(wl, des);
263 
264 			/*
265 			 * the handle data call can only fail in memory-outage
266 			 * conditions, in that case the received frame will just
267 			 * be dropped.
268 			 */
269 			if (wl1271_rx_handle_data(wl,
270 						  wl->aggr_buf + pkt_offset,
271 						  pkt_len, rx_align,
272 						  &hlid) == 1) {
273 				if (hlid < wl->num_links)
274 					__set_bit(hlid, active_hlids);
275 				else
276 					WARN(1,
277 					     "hlid (%d) exceeded MAX_LINKS\n",
278 					     hlid);
279 			}
280 
281 			wl->rx_counter++;
282 			drv_rx_counter++;
283 			drv_rx_counter %= wl->num_rx_desc;
284 			pkt_offset += wlcore_rx_get_align_buf_size(wl, pkt_len);
285 		}
286 	}
287 
288 	/*
289 	 * Write the driver's packet counter to the FW. This is only required
290 	 * for older hardware revisions
291 	 */
292 	if (wl->quirks & WLCORE_QUIRK_END_OF_TRANSACTION) {
293 		ret = wlcore_write32(wl, WL12XX_REG_RX_DRIVER_COUNTER,
294 				     wl->rx_counter);
295 		if (ret < 0)
296 			goto out;
297 	}
298 
299 	wl12xx_rearm_rx_streaming(wl, active_hlids);
300 
301 out:
302 	return ret;
303 }
304 
305 #ifdef CONFIG_PM
306 int wl1271_rx_filter_enable(struct wl1271 *wl,
307 			    int index, bool enable,
308 			    struct wl12xx_rx_filter *filter)
309 {
310 	int ret;
311 
312 	if (!!test_bit(index, wl->rx_filter_enabled) == enable) {
313 		wl1271_warning("Request to enable an already "
314 			     "enabled rx filter %d", index);
315 		return 0;
316 	}
317 
318 	ret = wl1271_acx_set_rx_filter(wl, index, enable, filter);
319 
320 	if (ret) {
321 		wl1271_error("Failed to %s rx data filter %d (err=%d)",
322 			     enable ? "enable" : "disable", index, ret);
323 		return ret;
324 	}
325 
326 	if (enable)
327 		__set_bit(index, wl->rx_filter_enabled);
328 	else
329 		__clear_bit(index, wl->rx_filter_enabled);
330 
331 	return 0;
332 }
333 
334 int wl1271_rx_filter_clear_all(struct wl1271 *wl)
335 {
336 	int i, ret = 0;
337 
338 	for (i = 0; i < WL1271_MAX_RX_FILTERS; i++) {
339 		if (!test_bit(i, wl->rx_filter_enabled))
340 			continue;
341 		ret = wl1271_rx_filter_enable(wl, i, 0, NULL);
342 		if (ret)
343 			goto out;
344 	}
345 
346 out:
347 	return ret;
348 }
349 #endif /* CONFIG_PM */
350