xref: /linux/drivers/net/wireless/nxp/nxpwifi/11n_aggr.c (revision 91ec2035134982b98fab0609a9fd8480e8217dc1)

// SPDX-License-Identifier: GPL-2.0-only
/*
 * nxpwifi: 802.11n Aggregation
 *
 * Copyright 2011-2024 NXP
 */

#include "cfg.h"
#include "util.h"
#include "fw.h"
#include "main.h"
#include "wmm.h"
#include "11n.h"
#include "11n_aggr.h"

/*
 * Build an AMSDU subframe for aggregation, with fields
 * (DA | SA | Length | SNAP header | MSDU), and compute padding
 * to align the subframe to a 4-byte boundary.
 */
static int nxpwifi_11n_form_amsdu_pkt(struct sk_buff *skb_aggr,
				      struct sk_buff *skb_src, int *pad)

{
	int dt_offset;
	struct rfc_1042_hdr snap = {
		0xaa,		/* LLC DSAP */
		0xaa,		/* LLC SSAP */
		0x03,		/* LLC CTRL */
		{0x00, 0x00, 0x00},	/* SNAP OUI */
		0x0000		/* SNAP type */
		/* This field will be overwritten later with ethertype */
	};
	struct tx_packet_hdr *tx_header;

	tx_header = skb_put(skb_aggr, sizeof(*tx_header));

	/* Copy DA and SA */
	dt_offset = 2 * ETH_ALEN;
	memcpy(&tx_header->eth803_hdr, skb_src->data, dt_offset);

	/* Copy SNAP header */
	snap.snap_type = ((struct ethhdr *)skb_src->data)->h_proto;

	dt_offset += sizeof(__be16);

	memcpy(&tx_header->rfc1042_hdr, &snap, sizeof(struct rfc_1042_hdr));

	skb_pull(skb_src, dt_offset);

	/* Update Length field */
	tx_header->eth803_hdr.h_proto = htons(skb_src->len + LLC_SNAP_LEN);

	/* Add payload */
	skb_put_data(skb_aggr, skb_src->data, skb_src->len);

	/* Add padding for new MSDU to start from 4 byte boundary */
	*pad = (4 - ((unsigned long)skb_aggr->tail & 0x3)) % 4;

	return skb_aggr->len + *pad;
}

/*
 * Adds TxPD to AMSDU header. Each AMSDU packet will contain one TxPD at the
 * beginning, followed by multiple AMSDU subframes
 */
static void
nxpwifi_11n_form_amsdu_txpd(struct nxpwifi_private *priv,
			    struct sk_buff *skb)
{
	struct txpd *local_tx_pd;

	skb_push(skb, sizeof(*local_tx_pd));

	local_tx_pd = (struct txpd *)skb->data;
	memset(local_tx_pd, 0, sizeof(struct txpd));

	/* Original priority has been overwritten */
	local_tx_pd->priority = (u8)skb->priority;
	local_tx_pd->pkt_delay_2ms =
		nxpwifi_wmm_compute_drv_pkt_delay(priv, skb);
	local_tx_pd->bss_num = priv->bss_num;
	local_tx_pd->bss_type = priv->bss_type;
	/* Always zero as the data is followed by struct txpd */
	local_tx_pd->tx_pkt_offset = cpu_to_le16(sizeof(struct txpd));
	local_tx_pd->tx_pkt_type = cpu_to_le16(PKT_TYPE_AMSDU);
	local_tx_pd->tx_pkt_length = cpu_to_le16(skb->len -
						 sizeof(*local_tx_pd));

	if (local_tx_pd->tx_control == 0)
		/* TxCtrl set by user or default */
		local_tx_pd->tx_control = cpu_to_le32(priv->pkt_tx_ctrl);

	if (GET_BSS_ROLE(priv) == NXPWIFI_BSS_ROLE_STA &&
	    priv->adapter->pps_uapsd_mode) {
		if (nxpwifi_check_last_packet_indication(priv)) {
			priv->adapter->tx_lock_flag = true;
			local_tx_pd->flags =
				NXPWIFI_TxPD_POWER_MGMT_LAST_PACKET;
		}
	}
}

/*
 * Build an aggregated MSDU packet by encapsulating buffers from the RA
 * list as AMSDU subframes and concatenating them. A TxPD is prepended
 * before transmission to form the final AMSDU packet.
 */
int
nxpwifi_11n_aggregate_pkt(struct nxpwifi_private *priv,
			  struct nxpwifi_ra_list_tbl *pra_list,
			  int ptrindex)
			  __releases(&priv->wmm.ra_list_spinlock)
{
	struct nxpwifi_adapter *adapter = priv->adapter;
	struct sk_buff *skb_aggr, *skb_src;
	struct nxpwifi_txinfo *tx_info_aggr, *tx_info_src;
	int pad = 0, aggr_num = 0, ret;
	struct nxpwifi_tx_param tx_param;
	struct txpd *ptx_pd = NULL;
	int headroom = adapter->intf_hdr_len;

	skb_src = skb_peek(&pra_list->skb_head);
	if (!skb_src) {
		spin_unlock_bh(&priv->wmm.ra_list_spinlock);
		return 0;
	}

	tx_info_src = NXPWIFI_SKB_TXCB(skb_src);
	skb_aggr = nxpwifi_alloc_dma_align_buf(adapter->tx_buf_size,
					       GFP_ATOMIC);
	if (!skb_aggr) {
		spin_unlock_bh(&priv->wmm.ra_list_spinlock);
		return -ENOMEM;
	}

	/*
	 * skb_aggr->data already 64 byte align, just reserve bus interface
	 * header and txpd.
	 */
	skb_reserve(skb_aggr, headroom + sizeof(struct txpd));
	tx_info_aggr =  NXPWIFI_SKB_TXCB(skb_aggr);

	memset(tx_info_aggr, 0, sizeof(*tx_info_aggr));
	tx_info_aggr->bss_type = tx_info_src->bss_type;
	tx_info_aggr->bss_num = tx_info_src->bss_num;

	tx_info_aggr->flags |= NXPWIFI_BUF_FLAG_AGGR_PKT;
	skb_aggr->priority = skb_src->priority;
	skb_aggr->tstamp = skb_src->tstamp;

	do {
		/* Check if AMSDU can accommodate this MSDU */
		if ((skb_aggr->len + skb_src->len + LLC_SNAP_LEN) >
		    adapter->tx_buf_size)
			break;

		skb_src = skb_dequeue(&pra_list->skb_head);
		pra_list->total_pkt_count--;
		atomic_dec(&priv->wmm.tx_pkts_queued);
		aggr_num++;
		spin_unlock_bh(&priv->wmm.ra_list_spinlock);
		nxpwifi_11n_form_amsdu_pkt(skb_aggr, skb_src, &pad);

		nxpwifi_write_data_complete(adapter, skb_src, 0, 0);

		spin_lock_bh(&priv->wmm.ra_list_spinlock);

		if (!nxpwifi_is_ralist_valid(priv, pra_list, ptrindex)) {
			spin_unlock_bh(&priv->wmm.ra_list_spinlock);
			return -ENOENT;
		}

		if (skb_tailroom(skb_aggr) < pad) {
			pad = 0;
			break;
		}
		skb_put(skb_aggr, pad);

		skb_src = skb_peek(&pra_list->skb_head);

	} while (skb_src);

	spin_unlock_bh(&priv->wmm.ra_list_spinlock);

	/* Last AMSDU packet does not need padding */
	skb_trim(skb_aggr, skb_aggr->len - pad);

	/* Form AMSDU */
	nxpwifi_11n_form_amsdu_txpd(priv, skb_aggr);
	if (GET_BSS_ROLE(priv) == NXPWIFI_BSS_ROLE_STA)
		ptx_pd = (struct txpd *)skb_aggr->data;

	skb_push(skb_aggr, headroom);
	tx_info_aggr->aggr_num = aggr_num * 2;
	if (adapter->data_sent || adapter->tx_lock_flag) {
		atomic_add(aggr_num * 2, &adapter->tx_queued);
		skb_queue_tail(&adapter->tx_data_q, skb_aggr);
		return 0;
	}

	if (skb_src)
		tx_param.next_pkt_len = skb_src->len + sizeof(struct txpd);
	else
		tx_param.next_pkt_len = 0;

	ret = adapter->if_ops.host_to_card(adapter, NXPWIFI_TYPE_DATA,
					   skb_aggr, &tx_param);

	switch (ret) {
	case -EBUSY:
		spin_lock_bh(&priv->wmm.ra_list_spinlock);
		if (!nxpwifi_is_ralist_valid(priv, pra_list, ptrindex)) {
			spin_unlock_bh(&priv->wmm.ra_list_spinlock);
			nxpwifi_write_data_complete(adapter, skb_aggr, 1, -1);
			return -EINVAL;
		}
		if (GET_BSS_ROLE(priv) == NXPWIFI_BSS_ROLE_STA &&
		    adapter->pps_uapsd_mode && adapter->tx_lock_flag) {
			priv->adapter->tx_lock_flag = false;
			if (ptx_pd)
				ptx_pd->flags = 0;
		}

		skb_queue_tail(&pra_list->skb_head, skb_aggr);

		pra_list->total_pkt_count++;

		atomic_inc(&priv->wmm.tx_pkts_queued);

		tx_info_aggr->flags |= NXPWIFI_BUF_FLAG_REQUEUED_PKT;
		spin_unlock_bh(&priv->wmm.ra_list_spinlock);
		nxpwifi_dbg(adapter, ERROR, "data: -EBUSY is returned\n");
		break;
	case -EINPROGRESS:
		break;
	case 0:
		nxpwifi_write_data_complete(adapter, skb_aggr, 1, ret);
		break;
	default:
		nxpwifi_dbg(adapter, ERROR, "%s: host_to_card failed: %#x\n",
			    __func__, ret);
		adapter->dbg.num_tx_host_to_card_failure++;
		nxpwifi_write_data_complete(adapter, skb_aggr, 1, ret);
		break;
	}
	if (ret != -EBUSY)
		nxpwifi_rotate_priolists(priv, pra_list, ptrindex);

	return 0;
}