wwan/iosm/iosm_ipc_mux.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * Copyright (C) 2020-21 Intel Corporation.
0004  */
0005
0006 #include "iosm_ipc_mux_codec.h"
0007
0008 /* At the begin of the runtime phase the IP MUX channel shall created. */
0009 static int ipc_mux_channel_create(struct iosm_mux *ipc_mux)
0010 {
0011     int channel_id;
0012
0013     channel_id = ipc_imem_channel_alloc(ipc_mux->imem, ipc_mux->instance_id,
0014                         IPC_CTYPE_WWAN);
0015
0016     if (channel_id < 0) {
0017         dev_err(ipc_mux->dev,
0018             "allocation of the MUX channel id failed");
0019         ipc_mux->state = MUX_S_ERROR;
0020         ipc_mux->event = MUX_E_NOT_APPLICABLE;
0021         goto no_channel;
0022     }
0023
0024     /* Establish the MUX channel in blocking mode. */
0025     ipc_mux->channel = ipc_imem_channel_open(ipc_mux->imem, channel_id,
0026                          IPC_HP_NET_CHANNEL_INIT);
0027
0028     if (!ipc_mux->channel) {
0029         dev_err(ipc_mux->dev, "ipc_imem_channel_open failed");
0030         ipc_mux->state = MUX_S_ERROR;
0031         ipc_mux->event = MUX_E_NOT_APPLICABLE;
0032         return -ENODEV; /* MUX channel is not available. */
0033     }
0034
0035     /* Define the MUX active state properties. */
0036     ipc_mux->state = MUX_S_ACTIVE;
0037     ipc_mux->event = MUX_E_NO_ORDERS;
0038
0039 no_channel:
0040     return channel_id;
0041 }
0042
0043 /* Reset the session/if id state. */
0044 static void ipc_mux_session_free(struct iosm_mux *ipc_mux, int if_id)
0045 {
0046     struct mux_session *if_entry;
0047
0048     if_entry = &ipc_mux->session[if_id];
0049     /* Reset the session state. */
0050     if_entry->wwan = NULL;
0051 }
0052
0053 /* Create and send the session open command. */
0054 static struct mux_cmd_open_session_resp *
0055 ipc_mux_session_open_send(struct iosm_mux *ipc_mux, int if_id)
0056 {
0057     struct mux_cmd_open_session_resp *open_session_resp;
0058     struct mux_acb *acb = &ipc_mux->acb;
0059     union mux_cmd_param param;
0060
0061     /* open_session commands to one ACB and start transmission. */
0062     param.open_session.flow_ctrl = 0;
0063     param.open_session.ipv4v6_hints = 0;
0064     param.open_session.reserved2 = 0;
0065     param.open_session.dl_head_pad_len = cpu_to_le32(IPC_MEM_DL_ETH_OFFSET);
0066
0067     /* Finish and transfer ACB. The user thread is suspended.
0068      * It is a blocking function call, until CP responds or timeout.
0069      */
0070     acb->wanted_response = MUX_CMD_OPEN_SESSION_RESP;
0071     if (ipc_mux_dl_acb_send_cmds(ipc_mux, MUX_CMD_OPEN_SESSION, if_id, 0,
0072                      &param, sizeof(param.open_session), true,
0073                  false) ||
0074         acb->got_response != MUX_CMD_OPEN_SESSION_RESP) {
0075         dev_err(ipc_mux->dev, "if_id %d: OPEN_SESSION send failed",
0076             if_id);
0077         return NULL;
0078     }
0079
0080     open_session_resp = &ipc_mux->acb.got_param.open_session_resp;
0081     if (open_session_resp->response != cpu_to_le32(MUX_CMD_RESP_SUCCESS)) {
0082         dev_err(ipc_mux->dev,
0083             "if_id %d,session open failed,response=%d", if_id,
0084             open_session_resp->response);
0085         return NULL;
0086     }
0087
0088     return open_session_resp;
0089 }
0090
0091 /* Open the first IP session. */
0092 static bool ipc_mux_session_open(struct iosm_mux *ipc_mux,
0093                  struct mux_session_open *session_open)
0094 {
0095     struct mux_cmd_open_session_resp *open_session_resp;
0096     int if_id;
0097
0098     /* Search for a free session interface id. */
0099     if_id = le32_to_cpu(session_open->if_id);
0100     if (if_id < 0 || if_id >= IPC_MEM_MUX_IP_SESSION_ENTRIES) {
0101         dev_err(ipc_mux->dev, "invalid interface id=%d", if_id);
0102         return false;
0103     }
0104
0105     /* Create and send the session open command.
0106      * It is a blocking function call, until CP responds or timeout.
0107      */
0108     open_session_resp = ipc_mux_session_open_send(ipc_mux, if_id);
0109     if (!open_session_resp) {
0110         ipc_mux_session_free(ipc_mux, if_id);
0111         session_open->if_id = cpu_to_le32(-1);
0112         return false;
0113     }
0114
0115     /* Initialize the uplink skb accumulator. */
0116     skb_queue_head_init(&ipc_mux->session[if_id].ul_list);
0117
0118     ipc_mux->session[if_id].dl_head_pad_len = IPC_MEM_DL_ETH_OFFSET;
0119     ipc_mux->session[if_id].ul_head_pad_len =
0120         le32_to_cpu(open_session_resp->ul_head_pad_len);
0121     ipc_mux->session[if_id].wwan = ipc_mux->wwan;
0122
0123     /* Reset the flow ctrl stats of the session */
0124     ipc_mux->session[if_id].flow_ctl_en_cnt = 0;
0125     ipc_mux->session[if_id].flow_ctl_dis_cnt = 0;
0126     ipc_mux->session[if_id].ul_flow_credits = 0;
0127     ipc_mux->session[if_id].net_tx_stop = false;
0128     ipc_mux->session[if_id].flow_ctl_mask = 0;
0129
0130     /* Save and return the assigned if id. */
0131     session_open->if_id = cpu_to_le32(if_id);
0132     ipc_mux->nr_sessions++;
0133
0134     return true;
0135 }
0136
0137 /* Free pending session UL packet. */
0138 static void ipc_mux_session_reset(struct iosm_mux *ipc_mux, int if_id)
0139 {
0140     /* Reset the session/if id state. */
0141     ipc_mux_session_free(ipc_mux, if_id);
0142
0143     /* Empty the uplink skb accumulator. */
0144     skb_queue_purge(&ipc_mux->session[if_id].ul_list);
0145 }
0146
0147 static void ipc_mux_session_close(struct iosm_mux *ipc_mux,
0148                   struct mux_session_close *msg)
0149 {
0150     int if_id;
0151
0152     /* Copy the session interface id. */
0153     if_id = le32_to_cpu(msg->if_id);
0154
0155     if (if_id < 0 || if_id >= IPC_MEM_MUX_IP_SESSION_ENTRIES) {
0156         dev_err(ipc_mux->dev, "invalid session id %d", if_id);
0157         return;
0158     }
0159
0160     /* Create and send the session close command.
0161      * It is a blocking function call, until CP responds or timeout.
0162      */
0163     if (ipc_mux_dl_acb_send_cmds(ipc_mux, MUX_CMD_CLOSE_SESSION, if_id, 0,
0164                      NULL, 0, true, false))
0165         dev_err(ipc_mux->dev, "if_id %d: CLOSE_SESSION send failed",
0166             if_id);
0167
0168     /* Reset the flow ctrl stats of the session */
0169     ipc_mux->session[if_id].flow_ctl_en_cnt = 0;
0170     ipc_mux->session[if_id].flow_ctl_dis_cnt = 0;
0171     ipc_mux->session[if_id].flow_ctl_mask = 0;
0172
0173     ipc_mux_session_reset(ipc_mux, if_id);
0174     ipc_mux->nr_sessions--;
0175 }
0176
0177 static void ipc_mux_channel_close(struct iosm_mux *ipc_mux,
0178                   struct mux_channel_close *channel_close_p)
0179 {
0180     int i;
0181
0182     /* Free pending session UL packet. */
0183     for (i = 0; i < IPC_MEM_MUX_IP_SESSION_ENTRIES; i++)
0184         if (ipc_mux->session[i].wwan)
0185             ipc_mux_session_reset(ipc_mux, i);
0186
0187     ipc_imem_channel_close(ipc_mux->imem, ipc_mux->channel_id);
0188
0189     /* Reset the MUX object. */
0190     ipc_mux->state = MUX_S_INACTIVE;
0191     ipc_mux->event = MUX_E_INACTIVE;
0192 }
0193
0194 /* CP has interrupted AP. If AP is in IP MUX mode, execute the pending ops. */
0195 static int ipc_mux_schedule(struct iosm_mux *ipc_mux, union mux_msg *msg)
0196 {
0197     enum mux_event order;
0198     bool success;
0199     int ret = -EIO;
0200
0201     if (!ipc_mux->initialized) {
0202         ret = -EAGAIN;
0203         goto out;
0204     }
0205
0206     order = msg->common.event;
0207
0208     switch (ipc_mux->state) {
0209     case MUX_S_INACTIVE:
0210         if (order != MUX_E_MUX_SESSION_OPEN)
0211             goto out; /* Wait for the request to open a session */
0212
0213         if (ipc_mux->event == MUX_E_INACTIVE)
0214             /* Establish the MUX channel and the new state. */
0215             ipc_mux->channel_id = ipc_mux_channel_create(ipc_mux);
0216
0217         if (ipc_mux->state != MUX_S_ACTIVE) {
0218             ret = ipc_mux->channel_id; /* Missing the MUX channel */
0219             goto out;
0220         }
0221
0222         /* Disable the TD update timer and open the first IP session. */
0223         ipc_imem_td_update_timer_suspend(ipc_mux->imem, true);
0224         ipc_mux->event = MUX_E_MUX_SESSION_OPEN;
0225         success = ipc_mux_session_open(ipc_mux, &msg->session_open);
0226
0227         ipc_imem_td_update_timer_suspend(ipc_mux->imem, false);
0228         if (success)
0229             ret = ipc_mux->channel_id;
0230         goto out;
0231
0232     case MUX_S_ACTIVE:
0233         switch (order) {
0234         case MUX_E_MUX_SESSION_OPEN:
0235             /* Disable the TD update timer and open a session */
0236             ipc_imem_td_update_timer_suspend(ipc_mux->imem, true);
0237             ipc_mux->event = MUX_E_MUX_SESSION_OPEN;
0238             success = ipc_mux_session_open(ipc_mux,
0239                                &msg->session_open);
0240             ipc_imem_td_update_timer_suspend(ipc_mux->imem, false);
0241             if (success)
0242                 ret = ipc_mux->channel_id;
0243             goto out;
0244
0245         case MUX_E_MUX_SESSION_CLOSE:
0246             /* Release an IP session. */
0247             ipc_mux->event = MUX_E_MUX_SESSION_CLOSE;
0248             ipc_mux_session_close(ipc_mux, &msg->session_close);
0249             if (!ipc_mux->nr_sessions) {
0250                 ipc_mux->event = MUX_E_MUX_CHANNEL_CLOSE;
0251                 ipc_mux_channel_close(ipc_mux,
0252                               &msg->channel_close);
0253             }
0254             ret = ipc_mux->channel_id;
0255             goto out;
0256
0257         case MUX_E_MUX_CHANNEL_CLOSE:
0258             /* Close the MUX channel pipes. */
0259             ipc_mux->event = MUX_E_MUX_CHANNEL_CLOSE;
0260             ipc_mux_channel_close(ipc_mux, &msg->channel_close);
0261             ret = ipc_mux->channel_id;
0262             goto out;
0263
0264         default:
0265             /* Invalid order. */
0266             goto out;
0267         }
0268
0269     default:
0270         dev_err(ipc_mux->dev,
0271             "unexpected MUX transition: state=%d, event=%d",
0272             ipc_mux->state, ipc_mux->event);
0273     }
0274 out:
0275     return ret;
0276 }
0277
0278 struct iosm_mux *ipc_mux_init(struct ipc_mux_config *mux_cfg,
0279                   struct iosm_imem *imem)
0280 {
0281     struct iosm_mux *ipc_mux = kzalloc(sizeof(*ipc_mux), GFP_KERNEL);
0282     int i, j, ul_tds, ul_td_size;
0283     struct sk_buff_head *free_list;
0284     struct sk_buff *skb;
0285     int qlt_size;
0286
0287     if (!ipc_mux)
0288         return NULL;
0289
0290     ipc_mux->protocol = mux_cfg->protocol;
0291     ipc_mux->ul_flow = mux_cfg->ul_flow;
0292     ipc_mux->instance_id = mux_cfg->instance_id;
0293     ipc_mux->wwan_q_offset = 0;
0294
0295     ipc_mux->pcie = imem->pcie;
0296     ipc_mux->imem = imem;
0297     ipc_mux->ipc_protocol = imem->ipc_protocol;
0298     ipc_mux->dev = imem->dev;
0299     ipc_mux->wwan = imem->wwan;
0300
0301     /* Get the reference to the UL ADB list. */
0302     free_list = &ipc_mux->ul_adb.free_list;
0303
0304     /* Initialize the list with free ADB. */
0305     skb_queue_head_init(free_list);
0306
0307     ul_td_size = IPC_MEM_MAX_DL_MUX_LITE_BUF_SIZE;
0308
0309     ul_tds = IPC_MEM_MAX_TDS_MUX_LITE_UL;
0310
0311     ipc_mux->ul_adb.dest_skb = NULL;
0312
0313     ipc_mux->initialized = true;
0314     ipc_mux->adb_prep_ongoing = false;
0315     ipc_mux->size_needed = 0;
0316     ipc_mux->ul_data_pend_bytes = 0;
0317     ipc_mux->state = MUX_S_INACTIVE;
0318     ipc_mux->ev_mux_net_transmit_pending = false;
0319     ipc_mux->tx_transaction_id = 0;
0320     ipc_mux->rr_next_session = 0;
0321     ipc_mux->event = MUX_E_INACTIVE;
0322     ipc_mux->channel_id = -1;
0323     ipc_mux->channel = NULL;
0324
0325     if (ipc_mux->protocol != MUX_LITE) {
0326         qlt_size = offsetof(struct mux_qlth, ql) +
0327                 MUX_QUEUE_LEVEL * sizeof(struct mux_qlth_ql);
0328
0329         for (i = 0; i < IPC_MEM_MUX_IP_SESSION_ENTRIES; i++) {
0330             ipc_mux->ul_adb.pp_qlt[i] = kzalloc(qlt_size,
0331                                 GFP_ATOMIC);
0332             if (!ipc_mux->ul_adb.pp_qlt[i]) {
0333                 for (j = i - 1; j >= 0; j--)
0334                     kfree(ipc_mux->ul_adb.pp_qlt[j]);
0335                 return NULL;
0336             }
0337         }
0338
0339         ul_td_size = IPC_MEM_MAX_UL_ADB_BUF_SIZE;
0340         ul_tds = IPC_MEM_MAX_TDS_MUX_AGGR_UL;
0341     }
0342
0343     /* Allocate the list of UL ADB. */
0344     for (i = 0; i < ul_tds; i++) {
0345         dma_addr_t mapping;
0346
0347         skb = ipc_pcie_alloc_skb(ipc_mux->pcie, ul_td_size, GFP_ATOMIC,
0348                      &mapping, DMA_TO_DEVICE, 0);
0349         if (!skb) {
0350             ipc_mux_deinit(ipc_mux);
0351             return NULL;
0352         }
0353         /* Extend the UL ADB list. */
0354         skb_queue_tail(free_list, skb);
0355     }
0356
0357     return ipc_mux;
0358 }
0359
0360 /* Informs the network stack to restart transmission for all opened session if
0361  * Flow Control is not ON for that session.
0362  */
0363 static void ipc_mux_restart_tx_for_all_sessions(struct iosm_mux *ipc_mux)
0364 {
0365     struct mux_session *session;
0366     int idx;
0367
0368     for (idx = 0; idx < IPC_MEM_MUX_IP_SESSION_ENTRIES; idx++) {
0369         session = &ipc_mux->session[idx];
0370
0371         if (!session->wwan)
0372             continue;
0373
0374         /* If flow control of the session is OFF and if there was tx
0375          * stop then restart. Inform the network interface to restart
0376          * sending data.
0377          */
0378         if (session->flow_ctl_mask == 0) {
0379             session->net_tx_stop = false;
0380             ipc_mux_netif_tx_flowctrl(session, idx, false);
0381         }
0382     }
0383 }
0384
0385 /* Informs the network stack to stop sending further pkt for all opened
0386  * sessions
0387  */
0388 static void ipc_mux_stop_netif_for_all_sessions(struct iosm_mux *ipc_mux)
0389 {
0390     struct mux_session *session;
0391     int idx;
0392
0393     for (idx = 0; idx < IPC_MEM_MUX_IP_SESSION_ENTRIES; idx++) {
0394         session = &ipc_mux->session[idx];
0395
0396         if (!session->wwan)
0397             continue;
0398
0399         ipc_mux_netif_tx_flowctrl(session, session->if_id, true);
0400     }
0401 }
0402
0403 void ipc_mux_check_n_restart_tx(struct iosm_mux *ipc_mux)
0404 {
0405     if (ipc_mux->ul_flow == MUX_UL) {
0406         int low_thresh = IPC_MEM_MUX_UL_FLOWCTRL_LOW_B;
0407
0408         if (ipc_mux->ul_data_pend_bytes < low_thresh)
0409             ipc_mux_restart_tx_for_all_sessions(ipc_mux);
0410     }
0411 }
0412
0413 int ipc_mux_get_max_sessions(struct iosm_mux *ipc_mux)
0414 {
0415     return ipc_mux ? IPC_MEM_MUX_IP_SESSION_ENTRIES : -EFAULT;
0416 }
0417
0418 enum ipc_mux_protocol ipc_mux_get_active_protocol(struct iosm_mux *ipc_mux)
0419 {
0420     return ipc_mux ? ipc_mux->protocol : MUX_UNKNOWN;
0421 }
0422
0423 int ipc_mux_open_session(struct iosm_mux *ipc_mux, int session_nr)
0424 {
0425     struct mux_session_open *session_open;
0426     union mux_msg mux_msg;
0427
0428     session_open = &mux_msg.session_open;
0429     session_open->event = MUX_E_MUX_SESSION_OPEN;
0430
0431     session_open->if_id = cpu_to_le32(session_nr);
0432     ipc_mux->session[session_nr].flags |= IPC_MEM_WWAN_MUX;
0433     return ipc_mux_schedule(ipc_mux, &mux_msg);
0434 }
0435
0436 int ipc_mux_close_session(struct iosm_mux *ipc_mux, int session_nr)
0437 {
0438     struct mux_session_close *session_close;
0439     union mux_msg mux_msg;
0440     int ret_val;
0441
0442     session_close = &mux_msg.session_close;
0443     session_close->event = MUX_E_MUX_SESSION_CLOSE;
0444
0445     session_close->if_id = cpu_to_le32(session_nr);
0446     ret_val = ipc_mux_schedule(ipc_mux, &mux_msg);
0447     ipc_mux->session[session_nr].flags &= ~IPC_MEM_WWAN_MUX;
0448
0449     return ret_val;
0450 }
0451
0452 void ipc_mux_deinit(struct iosm_mux *ipc_mux)
0453 {
0454     struct mux_channel_close *channel_close;
0455     struct sk_buff_head *free_list;
0456     union mux_msg mux_msg;
0457     struct sk_buff *skb;
0458
0459     if (!ipc_mux->initialized)
0460         return;
0461     ipc_mux_stop_netif_for_all_sessions(ipc_mux);
0462
0463     if (ipc_mux->state == MUX_S_ACTIVE) {
0464         channel_close = &mux_msg.channel_close;
0465         channel_close->event = MUX_E_MUX_CHANNEL_CLOSE;
0466         ipc_mux_schedule(ipc_mux, &mux_msg);
0467     }
0468
0469     /* Empty the ADB free list. */
0470     free_list = &ipc_mux->ul_adb.free_list;
0471
0472     /* Remove from the head of the downlink queue. */
0473     while ((skb = skb_dequeue(free_list)))
0474         ipc_pcie_kfree_skb(ipc_mux->pcie, skb);
0475
0476     if (ipc_mux->channel) {
0477         ipc_mux->channel->ul_pipe.is_open = false;
0478         ipc_mux->channel->dl_pipe.is_open = false;
0479     }
0480
0481     kfree(ipc_mux);
0482 }