Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / net / wireless / ti / wl1251 / rx.c
diff --git a/kernel/drivers/net/wireless/ti/wl1251/rx.c b/kernel/drivers/net/wireless/ti/wl1251/rx.c
new file mode 100644 (file)
index 0000000..cde0eaf
--- /dev/null
@@ -0,0 +1,235 @@
+/*
+ * This file is part of wl1251
+ *
+ * Copyright (c) 1998-2007 Texas Instruments Incorporated
+ * Copyright (C) 2008 Nokia Corporation
+ *
+ * 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/skbuff.h>
+#include <linux/gfp.h>
+#include <net/mac80211.h>
+
+#include "wl1251.h"
+#include "reg.h"
+#include "io.h"
+#include "rx.h"
+#include "cmd.h"
+#include "acx.h"
+
+static void wl1251_rx_header(struct wl1251 *wl,
+                            struct wl1251_rx_descriptor *desc)
+{
+       u32 rx_packet_ring_addr;
+
+       rx_packet_ring_addr = wl->data_path->rx_packet_ring_addr;
+       if (wl->rx_current_buffer)
+               rx_packet_ring_addr += wl->data_path->rx_packet_ring_chunk_size;
+
+       wl1251_mem_read(wl, rx_packet_ring_addr, desc, sizeof(*desc));
+}
+
+static void wl1251_rx_status(struct wl1251 *wl,
+                            struct wl1251_rx_descriptor *desc,
+                            struct ieee80211_rx_status *status,
+                            u8 beacon)
+{
+       u64 mactime;
+       int ret;
+
+       memset(status, 0, sizeof(struct ieee80211_rx_status));
+
+       status->band = IEEE80211_BAND_2GHZ;
+       status->mactime = desc->timestamp;
+
+       /*
+        * The rx status timestamp is a 32 bits value while the TSF is a
+        * 64 bits one.
+        * For IBSS merging, TSF is mandatory, so we have to get it
+        * somehow, so we ask for ACX_TSF_INFO.
+        * That could be moved to the get_tsf() hook, but unfortunately,
+        * this one must be atomic, while our SPI routines can sleep.
+        */
+       if ((wl->bss_type == BSS_TYPE_IBSS) && beacon) {
+               ret = wl1251_acx_tsf_info(wl, &mactime);
+               if (ret == 0)
+                       status->mactime = mactime;
+       }
+
+       status->signal = desc->rssi;
+
+       /*
+        * FIXME: guessing that snr needs to be divided by two, otherwise
+        * the values don't make any sense
+        */
+       wl->noise = desc->rssi - desc->snr / 2;
+
+       status->freq = ieee80211_channel_to_frequency(desc->channel,
+                                                     status->band);
+
+       status->flag |= RX_FLAG_MACTIME_START;
+
+       if (!wl->monitor_present && (desc->flags & RX_DESC_ENCRYPTION_MASK)) {
+               status->flag |= RX_FLAG_IV_STRIPPED | RX_FLAG_MMIC_STRIPPED;
+
+               if (likely(!(desc->flags & RX_DESC_DECRYPT_FAIL)))
+                       status->flag |= RX_FLAG_DECRYPTED;
+
+               if (unlikely(desc->flags & RX_DESC_MIC_FAIL))
+                       status->flag |= RX_FLAG_MMIC_ERROR;
+       }
+
+       if (unlikely(!(desc->flags & RX_DESC_VALID_FCS)))
+               status->flag |= RX_FLAG_FAILED_FCS_CRC;
+
+       switch (desc->rate) {
+               /* skip 1 and 12 Mbps because they have same value 0x0a */
+       case RATE_2MBPS:
+               status->rate_idx = 1;
+               break;
+       case RATE_5_5MBPS:
+               status->rate_idx = 2;
+               break;
+       case RATE_11MBPS:
+               status->rate_idx = 3;
+               break;
+       case RATE_6MBPS:
+               status->rate_idx = 4;
+               break;
+       case RATE_9MBPS:
+               status->rate_idx = 5;
+               break;
+       case RATE_18MBPS:
+               status->rate_idx = 7;
+               break;
+       case RATE_24MBPS:
+               status->rate_idx = 8;
+               break;
+       case RATE_36MBPS:
+               status->rate_idx = 9;
+               break;
+       case RATE_48MBPS:
+               status->rate_idx = 10;
+               break;
+       case RATE_54MBPS:
+               status->rate_idx = 11;
+               break;
+       }
+
+       /* for 1 and 12 Mbps we have to check the modulation */
+       if (desc->rate == RATE_1MBPS) {
+               if (!(desc->mod_pre & OFDM_RATE_BIT))
+                       /* CCK -> RATE_1MBPS */
+                       status->rate_idx = 0;
+               else
+                       /* OFDM -> RATE_12MBPS */
+                       status->rate_idx = 6;
+       }
+
+       if (desc->mod_pre & SHORT_PREAMBLE_BIT)
+               status->flag |= RX_FLAG_SHORTPRE;
+}
+
+static void wl1251_rx_body(struct wl1251 *wl,
+                          struct wl1251_rx_descriptor *desc)
+{
+       struct sk_buff *skb;
+       struct ieee80211_rx_status status;
+       u8 *rx_buffer, beacon = 0;
+       u16 length, *fc;
+       u32 curr_id, last_id_inc, rx_packet_ring_addr;
+
+       length = WL1251_RX_ALIGN(desc->length  - PLCP_HEADER_LENGTH);
+       curr_id = (desc->flags & RX_DESC_SEQNUM_MASK) >> RX_DESC_PACKETID_SHIFT;
+       last_id_inc = (wl->rx_last_id + 1) % (RX_MAX_PACKET_ID + 1);
+
+       if (last_id_inc != curr_id) {
+               wl1251_warning("curr ID:%d, last ID inc:%d",
+                              curr_id, last_id_inc);
+               wl->rx_last_id = curr_id;
+       } else {
+               wl->rx_last_id = last_id_inc;
+       }
+
+       rx_packet_ring_addr = wl->data_path->rx_packet_ring_addr +
+               sizeof(struct wl1251_rx_descriptor) + 20;
+       if (wl->rx_current_buffer)
+               rx_packet_ring_addr += wl->data_path->rx_packet_ring_chunk_size;
+
+       skb = __dev_alloc_skb(length, GFP_KERNEL);
+       if (!skb) {
+               wl1251_error("Couldn't allocate RX frame");
+               return;
+       }
+
+       rx_buffer = skb_put(skb, length);
+       wl1251_mem_read(wl, rx_packet_ring_addr, rx_buffer, length);
+
+       /* The actual length doesn't include the target's alignment */
+       skb_trim(skb, desc->length - PLCP_HEADER_LENGTH);
+
+       fc = (u16 *)skb->data;
+
+       if ((*fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_BEACON)
+               beacon = 1;
+
+       wl1251_rx_status(wl, desc, &status, beacon);
+
+       wl1251_debug(DEBUG_RX, "rx skb 0x%p: %d B %s", skb, skb->len,
+                    beacon ? "beacon" : "");
+
+       memcpy(IEEE80211_SKB_RXCB(skb), &status, sizeof(status));
+       ieee80211_rx_ni(wl->hw, skb);
+}
+
+static void wl1251_rx_ack(struct wl1251 *wl)
+{
+       u32 data, addr;
+
+       if (wl->rx_current_buffer) {
+               addr = ACX_REG_INTERRUPT_TRIG_H;
+               data = INTR_TRIG_RX_PROC1;
+       } else {
+               addr = ACX_REG_INTERRUPT_TRIG;
+               data = INTR_TRIG_RX_PROC0;
+       }
+
+       wl1251_reg_write32(wl, addr, data);
+
+       /* Toggle buffer ring */
+       wl->rx_current_buffer = !wl->rx_current_buffer;
+}
+
+
+void wl1251_rx(struct wl1251 *wl)
+{
+       struct wl1251_rx_descriptor *rx_desc;
+
+       if (wl->state != WL1251_STATE_ON)
+               return;
+
+       rx_desc = wl->rx_descriptor;
+
+       /* We first read the frame's header */
+       wl1251_rx_header(wl, rx_desc);
+
+       /* Now we can read the body */
+       wl1251_rx_body(wl, rx_desc);
+
+       /* Finally, we need to ACK the RX */
+       wl1251_rx_ack(wl);
+}