xref: /linux/drivers/net/wireless/ti/wlcore/rx.c (revision 93df8a1ed6231727c5db94a80b1a6bd5ee67cec3)
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. Desc: 0x%x",
98 				       desc_err_code);
99 		}
100 	}
101 
102 	if (beacon)
103 		wlcore_set_pending_regdomain_ch(wl, (u16)desc->channel,
104 						status->band);
105 }
106 
107 static int wl1271_rx_handle_data(struct wl1271 *wl, u8 *data, u32 length,
108 				 enum wl_rx_buf_align rx_align, u8 *hlid)
109 {
110 	struct wl1271_rx_descriptor *desc;
111 	struct sk_buff *skb;
112 	struct ieee80211_hdr *hdr;
113 	u8 *buf;
114 	u8 beacon = 0;
115 	u8 is_data = 0;
116 	u8 reserved = 0, offset_to_data = 0;
117 	u16 seq_num;
118 	u32 pkt_data_len;
119 
120 	/*
121 	 * In PLT mode we seem to get frames and mac80211 warns about them,
122 	 * workaround this by not retrieving them at all.
123 	 */
124 	if (unlikely(wl->plt))
125 		return -EINVAL;
126 
127 	pkt_data_len = wlcore_hw_get_rx_packet_len(wl, data, length);
128 	if (!pkt_data_len) {
129 		wl1271_error("Invalid packet arrived from HW. length %d",
130 			     length);
131 		return -EINVAL;
132 	}
133 
134 	if (rx_align == WLCORE_RX_BUF_UNALIGNED)
135 		reserved = RX_BUF_ALIGN;
136 	else if (rx_align == WLCORE_RX_BUF_PADDED)
137 		offset_to_data = RX_BUF_ALIGN;
138 
139 	/* the data read starts with the descriptor */
140 	desc = (struct wl1271_rx_descriptor *) data;
141 
142 	if (desc->packet_class == WL12XX_RX_CLASS_LOGGER) {
143 		size_t len = length - sizeof(*desc);
144 		wl12xx_copy_fwlog(wl, data + sizeof(*desc), len);
145 		wake_up_interruptible(&wl->fwlog_waitq);
146 		return 0;
147 	}
148 
149 	/* discard corrupted packets */
150 	if (desc->status & WL1271_RX_DESC_DECRYPT_FAIL) {
151 		hdr = (void *)(data + sizeof(*desc) + offset_to_data);
152 		wl1271_warning("corrupted packet in RX: status: 0x%x len: %d",
153 			       desc->status & WL1271_RX_DESC_STATUS_MASK,
154 			       pkt_data_len);
155 		wl1271_dump((DEBUG_RX|DEBUG_CMD), "PKT: ", data + sizeof(*desc),
156 			    min(pkt_data_len,
157 				ieee80211_hdrlen(hdr->frame_control)));
158 		return -EINVAL;
159 	}
160 
161 	/* skb length not including rx descriptor */
162 	skb = __dev_alloc_skb(pkt_data_len + reserved, GFP_KERNEL);
163 	if (!skb) {
164 		wl1271_error("Couldn't allocate RX frame");
165 		return -ENOMEM;
166 	}
167 
168 	/* reserve the unaligned payload(if any) */
169 	skb_reserve(skb, reserved);
170 
171 	buf = skb_put(skb, pkt_data_len);
172 
173 	/*
174 	 * Copy packets from aggregation buffer to the skbs without rx
175 	 * descriptor and with packet payload aligned care. In case of unaligned
176 	 * packets copy the packets in offset of 2 bytes guarantee IP header
177 	 * payload aligned to 4 bytes.
178 	 */
179 	memcpy(buf, data + sizeof(*desc), pkt_data_len);
180 	if (rx_align == WLCORE_RX_BUF_PADDED)
181 		skb_pull(skb, RX_BUF_ALIGN);
182 
183 	*hlid = desc->hlid;
184 
185 	hdr = (struct ieee80211_hdr *)skb->data;
186 	if (ieee80211_is_beacon(hdr->frame_control))
187 		beacon = 1;
188 	if (ieee80211_is_data_present(hdr->frame_control))
189 		is_data = 1;
190 
191 	wl1271_rx_status(wl, desc, IEEE80211_SKB_RXCB(skb), beacon);
192 	wlcore_hw_set_rx_csum(wl, desc, skb);
193 
194 	seq_num = (le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_SEQ) >> 4;
195 	wl1271_debug(DEBUG_RX, "rx skb 0x%p: %d B %s seq %d hlid %d", skb,
196 		     skb->len - desc->pad_len,
197 		     beacon ? "beacon" : "",
198 		     seq_num, *hlid);
199 
200 	skb_queue_tail(&wl->deferred_rx_queue, skb);
201 	queue_work(wl->freezable_wq, &wl->netstack_work);
202 
203 	return is_data;
204 }
205 
206 int wlcore_rx(struct wl1271 *wl, struct wl_fw_status *status)
207 {
208 	unsigned long active_hlids[BITS_TO_LONGS(WLCORE_MAX_LINKS)] = {0};
209 	u32 buf_size;
210 	u32 fw_rx_counter = status->fw_rx_counter % wl->num_rx_desc;
211 	u32 drv_rx_counter = wl->rx_counter % wl->num_rx_desc;
212 	u32 rx_counter;
213 	u32 pkt_len, align_pkt_len;
214 	u32 pkt_offset, des;
215 	u8 hlid;
216 	enum wl_rx_buf_align rx_align;
217 	int ret = 0;
218 
219 	while (drv_rx_counter != fw_rx_counter) {
220 		buf_size = 0;
221 		rx_counter = drv_rx_counter;
222 		while (rx_counter != fw_rx_counter) {
223 			des = le32_to_cpu(status->rx_pkt_descs[rx_counter]);
224 			pkt_len = wlcore_rx_get_buf_size(wl, des);
225 			align_pkt_len = wlcore_rx_get_align_buf_size(wl,
226 								     pkt_len);
227 			if (buf_size + align_pkt_len > wl->aggr_buf_size)
228 				break;
229 			buf_size += align_pkt_len;
230 			rx_counter++;
231 			rx_counter %= wl->num_rx_desc;
232 		}
233 
234 		if (buf_size == 0) {
235 			wl1271_warning("received empty data");
236 			break;
237 		}
238 
239 		/* Read all available packets at once */
240 		des = le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]);
241 		ret = wlcore_hw_prepare_read(wl, des, buf_size);
242 		if (ret < 0)
243 			goto out;
244 
245 		ret = wlcore_read_data(wl, REG_SLV_MEM_DATA, wl->aggr_buf,
246 				       buf_size, true);
247 		if (ret < 0)
248 			goto out;
249 
250 		/* Split data into separate packets */
251 		pkt_offset = 0;
252 		while (pkt_offset < buf_size) {
253 			des = le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]);
254 			pkt_len = wlcore_rx_get_buf_size(wl, des);
255 			rx_align = wlcore_hw_get_rx_buf_align(wl, des);
256 
257 			/*
258 			 * the handle data call can only fail in memory-outage
259 			 * conditions, in that case the received frame will just
260 			 * be dropped.
261 			 */
262 			if (wl1271_rx_handle_data(wl,
263 						  wl->aggr_buf + pkt_offset,
264 						  pkt_len, rx_align,
265 						  &hlid) == 1) {
266 				if (hlid < wl->num_links)
267 					__set_bit(hlid, active_hlids);
268 				else
269 					WARN(1,
270 					     "hlid (%d) exceeded MAX_LINKS\n",
271 					     hlid);
272 			}
273 
274 			wl->rx_counter++;
275 			drv_rx_counter++;
276 			drv_rx_counter %= wl->num_rx_desc;
277 			pkt_offset += wlcore_rx_get_align_buf_size(wl, pkt_len);
278 		}
279 	}
280 
281 	/*
282 	 * Write the driver's packet counter to the FW. This is only required
283 	 * for older hardware revisions
284 	 */
285 	if (wl->quirks & WLCORE_QUIRK_END_OF_TRANSACTION) {
286 		ret = wlcore_write32(wl, WL12XX_REG_RX_DRIVER_COUNTER,
287 				     wl->rx_counter);
288 		if (ret < 0)
289 			goto out;
290 	}
291 
292 	wl12xx_rearm_rx_streaming(wl, active_hlids);
293 
294 out:
295 	return ret;
296 }
297 
298 #ifdef CONFIG_PM
299 int wl1271_rx_filter_enable(struct wl1271 *wl,
300 			    int index, bool enable,
301 			    struct wl12xx_rx_filter *filter)
302 {
303 	int ret;
304 
305 	if (!!test_bit(index, wl->rx_filter_enabled) == enable) {
306 		wl1271_warning("Request to enable an already "
307 			     "enabled rx filter %d", index);
308 		return 0;
309 	}
310 
311 	ret = wl1271_acx_set_rx_filter(wl, index, enable, filter);
312 
313 	if (ret) {
314 		wl1271_error("Failed to %s rx data filter %d (err=%d)",
315 			     enable ? "enable" : "disable", index, ret);
316 		return ret;
317 	}
318 
319 	if (enable)
320 		__set_bit(index, wl->rx_filter_enabled);
321 	else
322 		__clear_bit(index, wl->rx_filter_enabled);
323 
324 	return 0;
325 }
326 
327 int wl1271_rx_filter_clear_all(struct wl1271 *wl)
328 {
329 	int i, ret = 0;
330 
331 	for (i = 0; i < WL1271_MAX_RX_FILTERS; i++) {
332 		if (!test_bit(i, wl->rx_filter_enabled))
333 			continue;
334 		ret = wl1271_rx_filter_enable(wl, i, 0, NULL);
335 		if (ret)
336 			goto out;
337 	}
338 
339 out:
340 	return ret;
341 }
342 #endif /* CONFIG_PM */
343