summaryrefslogtreecommitdiff
path: root/drivers/net/wireless/wl12xx/rx.c
blob: ec8d843d41cfd4198f3dd4c7fe25f43d244a2e02 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
/*
 * This file is part of wl1271
 *
 * Copyright (C) 2009 Nokia Corporation
 *
 * Contact: Luciano Coelho <luciano.coelho@nokia.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 *
 */

#include <linux/gfp.h>

#include "wl12xx.h"
#include "acx.h"
#include "reg.h"
#include "rx.h"
#include "io.h"

static u8 wl1271_rx_get_mem_block(struct wl1271_fw_status *status,
				  u32 drv_rx_counter)
{
	return le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]) &
		RX_MEM_BLOCK_MASK;
}

static u32 wl1271_rx_get_buf_size(struct wl1271_fw_status *status,
				 u32 drv_rx_counter)
{
	return (le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]) &
		RX_BUF_SIZE_MASK) >> RX_BUF_SIZE_SHIFT_DIV;
}

static void wl1271_rx_status(struct wl1271 *wl,
			     struct wl1271_rx_descriptor *desc,
			     struct ieee80211_rx_status *status,
			     u8 beacon)
{
	enum ieee80211_band desc_band;

	memset(status, 0, sizeof(struct ieee80211_rx_status));

	status->band = wl->band;

	if ((desc->flags & WL1271_RX_DESC_BAND_MASK) == WL1271_RX_DESC_BAND_BG)
		desc_band = IEEE80211_BAND_2GHZ;
	else
		desc_band = IEEE80211_BAND_5GHZ;

	status->rate_idx = wl1271_rate_to_idx(desc->rate, desc_band);

#ifdef CONFIG_WL12XX_HT
	/* 11n support */
	if (desc->rate <= CONF_HW_RXTX_RATE_MCS0)
		status->flag |= RX_FLAG_HT;
#endif

	status->signal = desc->rssi;

	/*
	 * FIXME: In wl1251, the SNR should be divided by two.  In wl1271 we
	 * need to divide by two for now, but TI has been discussing about
	 * changing it.  This needs to be rechecked.
	 */
	wl->noise = desc->rssi - (desc->snr >> 1);

	status->freq = ieee80211_channel_to_frequency(desc->channel, desc_band);

	if (desc->flags & WL1271_RX_DESC_ENCRYPT_MASK) {
		status->flag |= RX_FLAG_IV_STRIPPED | RX_FLAG_MMIC_STRIPPED;

		if (likely(!(desc->status & WL1271_RX_DESC_DECRYPT_FAIL)))
			status->flag |= RX_FLAG_DECRYPTED;
		if (unlikely(desc->status & WL1271_RX_DESC_MIC_FAIL))
			status->flag |= RX_FLAG_MMIC_ERROR;
	}
}

static int wl1271_rx_handle_data(struct wl1271 *wl, u8 *data, u32 length)
{
	struct wl1271_rx_descriptor *desc;
	struct sk_buff *skb;
	u16 *fc;
	u8 *buf;
	u8 beacon = 0;

	/*
	 * In PLT mode we seem to get frames and mac80211 warns about them,
	 * workaround this by not retrieving them at all.
	 */
	if (unlikely(wl->state == WL1271_STATE_PLT))
		return -EINVAL;

	skb = __dev_alloc_skb(length, GFP_KERNEL);
	if (!skb) {
		wl1271_error("Couldn't allocate RX frame");
		return -ENOMEM;
	}

	buf = skb_put(skb, length);
	memcpy(buf, data, length);

	/* the data read starts with the descriptor */
	desc = (struct wl1271_rx_descriptor *) buf;

	/* now we pull the descriptor out of the buffer */
	skb_pull(skb, sizeof(*desc));

	fc = (u16 *)skb->data;
	if ((*fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_BEACON)
		beacon = 1;

	wl1271_rx_status(wl, desc, IEEE80211_SKB_RXCB(skb), beacon);

	wl1271_debug(DEBUG_RX, "rx skb 0x%p: %d B %s", skb, skb->len,
		     beacon ? "beacon" : "");

	skb_trim(skb, skb->len - desc->pad_len);

	ieee80211_rx_ni(wl->hw, skb);

	return 0;
}

void wl1271_rx(struct wl1271 *wl, struct wl1271_fw_status *status)
{
	struct wl1271_acx_mem_map *wl_mem_map = wl->target_mem_map;
	u32 buf_size;
	u32 fw_rx_counter  = status->fw_rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
	u32 drv_rx_counter = wl->rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
	u32 rx_counter;
	u32 mem_block;
	u32 pkt_length;
	u32 pkt_offset;

	while (drv_rx_counter != fw_rx_counter) {
		buf_size = 0;
		rx_counter = drv_rx_counter;
		while (rx_counter != fw_rx_counter) {
			pkt_length = wl1271_rx_get_buf_size(status, rx_counter);
			if (buf_size + pkt_length > WL1271_AGGR_BUFFER_SIZE)
				break;
			buf_size += pkt_length;
			rx_counter++;
			rx_counter &= NUM_RX_PKT_DESC_MOD_MASK;
		}

		if (buf_size == 0) {
			wl1271_warning("received empty data");
			break;
		}

		/*
		 * Choose the block we want to read
		 * For aggregated packets, only the first memory block should
		 * be retrieved. The FW takes care of the rest.
		 */
		mem_block = wl1271_rx_get_mem_block(status, drv_rx_counter);
		wl->rx_mem_pool_addr.addr = (mem_block << 8) +
			le32_to_cpu(wl_mem_map->packet_memory_pool_start);
		wl->rx_mem_pool_addr.addr_extra =
			wl->rx_mem_pool_addr.addr + 4;
		wl1271_write(wl, WL1271_SLV_REG_DATA, &wl->rx_mem_pool_addr,
				sizeof(wl->rx_mem_pool_addr), false);

		/* Read all available packets at once */
		wl1271_read(wl, WL1271_SLV_MEM_DATA, wl->aggr_buf,
				buf_size, true);

		/* Split data into separate packets */
		pkt_offset = 0;
		while (pkt_offset < buf_size) {
			pkt_length = wl1271_rx_get_buf_size(status,
					drv_rx_counter);
			/*
			 * the handle data call can only fail in memory-outage
			 * conditions, in that case the received frame will just
			 * be dropped.
			 */
			wl1271_rx_handle_data(wl,
					      wl->aggr_buf + pkt_offset,
					      pkt_length);
			wl->rx_counter++;
			drv_rx_counter++;
			drv_rx_counter &= NUM_RX_PKT_DESC_MOD_MASK;
			pkt_offset += pkt_length;
		}
	}
	wl1271_write32(wl, RX_DRIVER_COUNTER_ADDRESS,
			cpu_to_le32(wl->rx_counter));
}