xref: /openbmc/linux/drivers/net/wireless/ti/wlcore/rx.c (revision eb96f841)
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 = RX_BUF_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, RX_BUF_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 	wlcore_hw_set_rx_csum(wl, desc, skb);
190 
191 	seq_num = (le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_SEQ) >> 4;
192 	wl1271_debug(DEBUG_RX, "rx skb 0x%p: %d B %s seq %d hlid %d", skb,
193 		     skb->len - desc->pad_len,
194 		     beacon ? "beacon" : "",
195 		     seq_num, *hlid);
196 
197 	skb_queue_tail(&wl->deferred_rx_queue, skb);
198 	queue_work(wl->freezable_wq, &wl->netstack_work);
199 
200 	return is_data;
201 }
202 
203 int wlcore_rx(struct wl1271 *wl, struct wl_fw_status_1 *status)
204 {
205 	unsigned long active_hlids[BITS_TO_LONGS(WL12XX_MAX_LINKS)] = {0};
206 	u32 buf_size;
207 	u32 fw_rx_counter = status->fw_rx_counter % wl->num_rx_desc;
208 	u32 drv_rx_counter = wl->rx_counter % wl->num_rx_desc;
209 	u32 rx_counter;
210 	u32 pkt_len, align_pkt_len;
211 	u32 pkt_offset, des;
212 	u8 hlid;
213 	enum wl_rx_buf_align rx_align;
214 	int ret = 0;
215 
216 	while (drv_rx_counter != fw_rx_counter) {
217 		buf_size = 0;
218 		rx_counter = drv_rx_counter;
219 		while (rx_counter != fw_rx_counter) {
220 			des = le32_to_cpu(status->rx_pkt_descs[rx_counter]);
221 			pkt_len = wlcore_rx_get_buf_size(wl, des);
222 			align_pkt_len = wlcore_rx_get_align_buf_size(wl,
223 								     pkt_len);
224 			if (buf_size + align_pkt_len > WL1271_AGGR_BUFFER_SIZE)
225 				break;
226 			buf_size += align_pkt_len;
227 			rx_counter++;
228 			rx_counter %= wl->num_rx_desc;
229 		}
230 
231 		if (buf_size == 0) {
232 			wl1271_warning("received empty data");
233 			break;
234 		}
235 
236 		/* Read all available packets at once */
237 		des = le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]);
238 		ret = wlcore_hw_prepare_read(wl, des, buf_size);
239 		if (ret < 0)
240 			goto out;
241 
242 		ret = wlcore_read_data(wl, REG_SLV_MEM_DATA, wl->aggr_buf,
243 				       buf_size, true);
244 		if (ret < 0)
245 			goto out;
246 
247 		/* Split data into separate packets */
248 		pkt_offset = 0;
249 		while (pkt_offset < buf_size) {
250 			des = le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]);
251 			pkt_len = wlcore_rx_get_buf_size(wl, des);
252 			rx_align = wlcore_hw_get_rx_buf_align(wl, des);
253 
254 			/*
255 			 * the handle data call can only fail in memory-outage
256 			 * conditions, in that case the received frame will just
257 			 * be dropped.
258 			 */
259 			if (wl1271_rx_handle_data(wl,
260 						  wl->aggr_buf + pkt_offset,
261 						  pkt_len, rx_align,
262 						  &hlid) == 1) {
263 				if (hlid < WL12XX_MAX_LINKS)
264 					__set_bit(hlid, active_hlids);
265 				else
266 					WARN(1,
267 					     "hlid exceeded WL12XX_MAX_LINKS "
268 					     "(%d)\n", hlid);
269 			}
270 
271 			wl->rx_counter++;
272 			drv_rx_counter++;
273 			drv_rx_counter %= wl->num_rx_desc;
274 			pkt_offset += wlcore_rx_get_align_buf_size(wl, pkt_len);
275 		}
276 	}
277 
278 	/*
279 	 * Write the driver's packet counter to the FW. This is only required
280 	 * for older hardware revisions
281 	 */
282 	if (wl->quirks & WLCORE_QUIRK_END_OF_TRANSACTION)
283 		wl1271_write32(wl, WL12XX_REG_RX_DRIVER_COUNTER,
284 			       wl->rx_counter);
285 
286 	wl12xx_rearm_rx_streaming(wl, active_hlids);
287 
288 out:
289 	return ret;
290 }
291 
292 #ifdef CONFIG_PM
293 int wl1271_rx_filter_enable(struct wl1271 *wl,
294 			    int index, bool enable,
295 			    struct wl12xx_rx_filter *filter)
296 {
297 	int ret;
298 
299 	if (wl->rx_filter_enabled[index] == enable) {
300 		wl1271_warning("Request to enable an already "
301 			     "enabled rx filter %d", index);
302 		return 0;
303 	}
304 
305 	ret = wl1271_acx_set_rx_filter(wl, index, enable, filter);
306 
307 	if (ret) {
308 		wl1271_error("Failed to %s rx data filter %d (err=%d)",
309 			     enable ? "enable" : "disable", index, ret);
310 		return ret;
311 	}
312 
313 	wl->rx_filter_enabled[index] = enable;
314 
315 	return 0;
316 }
317 
318 void wl1271_rx_filter_clear_all(struct wl1271 *wl)
319 {
320 	int i;
321 
322 	for (i = 0; i < WL1271_MAX_RX_FILTERS; i++) {
323 		if (!wl->rx_filter_enabled[i])
324 			continue;
325 		wl1271_rx_filter_enable(wl, i, 0, NULL);
326 	}
327 }
328 #endif /* CONFIG_PM */
329