drivers/mailbox/imx-mailbox.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2018 Pengutronix, Oleksij Rempel <o.rempel@pengutronix.de>
   4  * Copyright 2022 NXP, Peng Fan <peng.fan@nxp.com>
   5  */
   6
   7 #include <linux/clk.h>
   8 #include <linux/firmware/imx/ipc.h>
   9 #include <linux/firmware/imx/s4.h>
  10 #include <linux/interrupt.h>
  11 #include <linux/io.h>
  12 #include <linux/iopoll.h>
  13 #include <linux/jiffies.h>
  14 #include <linux/kernel.h>
  15 #include <linux/mailbox_controller.h>
  16 #include <linux/module.h>
  17 #include <linux/of_device.h>
  18 #include <linux/pm_runtime.h>
  19 #include <linux/suspend.h>
  20 #include <linux/slab.h>
  21
  22 #define IMX_MU_CHANS            17
  23 /* TX0/RX0/RXDB[0-3] */
  24 #define IMX_MU_SCU_CHANS        6
  25 /* TX0/RX0 */
  26 #define IMX_MU_S4_CHANS         2
  27 #define IMX_MU_CHAN_NAME_SIZE   20
  28
  29 #define IMX_MU_NUM_RR           4
  30
  31 #define IMX_MU_SECO_TX_TOUT (msecs_to_jiffies(3000))
  32 #define IMX_MU_SECO_RX_TOUT (msecs_to_jiffies(3000))
  33
  34 /* Please not change TX & RX */
  35 enum imx_mu_chan_type {
  36         IMX_MU_TYPE_TX          = 0, /* Tx */
  37         IMX_MU_TYPE_RX          = 1, /* Rx */
  38         IMX_MU_TYPE_TXDB        = 2, /* Tx doorbell */
  39         IMX_MU_TYPE_RXDB        = 3, /* Rx doorbell */
  40         IMX_MU_TYPE_RST         = 4, /* Reset */
  41 };
  42
  43 enum imx_mu_xcr {
  44         IMX_MU_CR,
  45         IMX_MU_GIER,
  46         IMX_MU_GCR,
  47         IMX_MU_TCR,
  48         IMX_MU_RCR,
  49         IMX_MU_xCR_MAX,
  50 };
  51
  52 enum imx_mu_xsr {
  53         IMX_MU_SR,
  54         IMX_MU_GSR,
  55         IMX_MU_TSR,
  56         IMX_MU_RSR,
  57         IMX_MU_xSR_MAX,
  58 };
  59
  60 struct imx_sc_rpc_msg_max {
  61         struct imx_sc_rpc_msg hdr;
  62         u32 data[30];
  63 };
  64
  65 struct imx_s4_rpc_msg_max {
  66         struct imx_s4_rpc_msg hdr;
  67         u32 data[254];
  68 };
  69
  70 struct imx_mu_con_priv {
  71         unsigned int            idx;
  72         char                    irq_desc[IMX_MU_CHAN_NAME_SIZE];
  73         enum imx_mu_chan_type   type;
  74         struct mbox_chan        *chan;
  75         struct tasklet_struct   txdb_tasklet;
  76 };
  77
  78 struct imx_mu_priv {
  79         struct device           *dev;
  80         void __iomem            *base;
  81         void                    *msg;
  82         spinlock_t              xcr_lock; /* control register lock */
  83
  84         struct mbox_controller  mbox;
  85         struct mbox_chan        mbox_chans[IMX_MU_CHANS];
  86
  87         struct imx_mu_con_priv  con_priv[IMX_MU_CHANS];
  88         const struct imx_mu_dcfg        *dcfg;
  89         struct clk              *clk;
  90         int                     irq[IMX_MU_CHANS];
  91         bool                    suspend;
  92
  93         u32 xcr[IMX_MU_xCR_MAX];
  94
  95         bool                    side_b;
  96 };
  97
  98 enum imx_mu_type {
  99         IMX_MU_V1,
 100         IMX_MU_V2 = BIT(1),
 101         IMX_MU_V2_S4 = BIT(15),
 102         IMX_MU_V2_IRQ = BIT(16),
 103 };
 104
 105 struct imx_mu_dcfg {
 106         int (*tx)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp, void *data);
 107         int (*rx)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp);
 108         int (*rxdb)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp);
 109         void (*init)(struct imx_mu_priv *priv);
 110         enum imx_mu_type type;
 111         u32     xTR;            /* Transmit Register0 */
 112         u32     xRR;            /* Receive Register0 */
 113         u32     xSR[IMX_MU_xSR_MAX];    /* Status Registers */
 114         u32     xCR[IMX_MU_xCR_MAX];    /* Control Registers */
 115 };
 116
 117 #define IMX_MU_xSR_GIPn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(28 + (3 - (x))))
 118 #define IMX_MU_xSR_RFn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(24 + (3 - (x))))
 119 #define IMX_MU_xSR_TEn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(20 + (3 - (x))))
 120
 121 /* General Purpose Interrupt Enable */
 122 #define IMX_MU_xCR_GIEn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(28 + (3 - (x))))
 123 /* Receive Interrupt Enable */
 124 #define IMX_MU_xCR_RIEn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(24 + (3 - (x))))
 125 /* Transmit Interrupt Enable */
 126 #define IMX_MU_xCR_TIEn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(20 + (3 - (x))))
 127 /* General Purpose Interrupt Request */
 128 #define IMX_MU_xCR_GIRn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(16 + (3 - (x))))
 129 /* MU reset */
 130 #define IMX_MU_xCR_RST(type)    (type & IMX_MU_V2 ? BIT(0) : BIT(5))
 131 #define IMX_MU_xSR_RST(type)    (type & IMX_MU_V2 ? BIT(0) : BIT(7))
 132
 133
 134 static struct imx_mu_priv *to_imx_mu_priv(struct mbox_controller *mbox)
 135 {
 136         return container_of(mbox, struct imx_mu_priv, mbox);
 137 }
 138
 139 static void imx_mu_write(struct imx_mu_priv *priv, u32 val, u32 offs)
 140 {
 141         iowrite32(val, priv->base + offs);
 142 }
 143
 144 static u32 imx_mu_read(struct imx_mu_priv *priv, u32 offs)
 145 {
 146         return ioread32(priv->base + offs);
 147 }
 148
 149 static int imx_mu_tx_waiting_write(struct imx_mu_priv *priv, u32 val, u32 idx)
 150 {
 151         u64 timeout_time = get_jiffies_64() + IMX_MU_SECO_TX_TOUT;
 152         u32 status;
 153         u32 can_write;
 154
 155         dev_dbg(priv->dev, "Trying to write %.8x to idx %d\n", val, idx);
 156
 157         do {
 158                 status = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_TSR]);
 159                 can_write = status & IMX_MU_xSR_TEn(priv->dcfg->type, idx % 4);
 160         } while (!can_write && time_is_after_jiffies64(timeout_time));
 161
 162         if (!can_write) {
 163                 dev_err(priv->dev, "timeout trying to write %.8x at %d(%.8x)\n",
 164                         val, idx, status);
 165                 return -ETIME;
 166         }
 167
 168         imx_mu_write(priv, val, priv->dcfg->xTR + (idx % 4) * 4);
 169
 170         return 0;
 171 }
 172
 173 static int imx_mu_rx_waiting_read(struct imx_mu_priv *priv, u32 *val, u32 idx)
 174 {
 175         u64 timeout_time = get_jiffies_64() + IMX_MU_SECO_RX_TOUT;
 176         u32 status;
 177         u32 can_read;
 178
 179         dev_dbg(priv->dev, "Trying to read from idx %d\n", idx);
 180
 181         do {
 182                 status = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_RSR]);
 183                 can_read = status & IMX_MU_xSR_RFn(priv->dcfg->type, idx % 4);
 184         } while (!can_read && time_is_after_jiffies64(timeout_time));
 185
 186         if (!can_read) {
 187                 dev_err(priv->dev, "timeout trying to read idx %d (%.8x)\n",
 188                         idx, status);
 189                 return -ETIME;
 190         }
 191
 192         *val = imx_mu_read(priv, priv->dcfg->xRR + (idx % 4) * 4);
 193         dev_dbg(priv->dev, "Read %.8x\n", *val);
 194
 195         return 0;
 196 }
 197
 198 static u32 imx_mu_xcr_rmw(struct imx_mu_priv *priv, enum imx_mu_xcr type, u32 set, u32 clr)
 199 {
 200         unsigned long flags;
 201         u32 val;
 202
 203         spin_lock_irqsave(&priv->xcr_lock, flags);
 204         val = imx_mu_read(priv, priv->dcfg->xCR[type]);
 205         val &= ~clr;
 206         val |= set;
 207         imx_mu_write(priv, val, priv->dcfg->xCR[type]);
 208         spin_unlock_irqrestore(&priv->xcr_lock, flags);
 209
 210         return val;
 211 }
 212
 213 static int imx_mu_generic_tx(struct imx_mu_priv *priv,
 214                              struct imx_mu_con_priv *cp,
 215                              void *data)
 216 {
 217         u32 *arg = data;
 218
 219         switch (cp->type) {
 220         case IMX_MU_TYPE_TX:
 221                 imx_mu_write(priv, *arg, priv->dcfg->xTR + cp->idx * 4);
 222                 imx_mu_xcr_rmw(priv, IMX_MU_TCR, IMX_MU_xCR_TIEn(priv->dcfg->type, cp->idx), 0);
 223                 break;
 224         case IMX_MU_TYPE_TXDB:
 225                 imx_mu_xcr_rmw(priv, IMX_MU_GCR, IMX_MU_xCR_GIRn(priv->dcfg->type, cp->idx), 0);
 226                 tasklet_schedule(&cp->txdb_tasklet);
 227                 break;
 228         default:
 229                 dev_warn_ratelimited(priv->dev, "Send data on wrong channel type: %d\n", cp->type);
 230                 return -EINVAL;
 231         }
 232
 233         return 0;
 234 }
 235
 236 static int imx_mu_generic_rx(struct imx_mu_priv *priv,
 237                              struct imx_mu_con_priv *cp)
 238 {
 239         u32 dat;
 240
 241         dat = imx_mu_read(priv, priv->dcfg->xRR + (cp->idx) * 4);
 242         mbox_chan_received_data(cp->chan, (void *)&dat);
 243
 244         return 0;
 245 }
 246
 247 static int imx_mu_generic_rxdb(struct imx_mu_priv *priv,
 248                                struct imx_mu_con_priv *cp)
 249 {
 250         imx_mu_write(priv, IMX_MU_xSR_GIPn(priv->dcfg->type, cp->idx),
 251                      priv->dcfg->xSR[IMX_MU_GSR]);
 252         mbox_chan_received_data(cp->chan, NULL);
 253
 254         return 0;
 255 }
 256
 257 static int imx_mu_specific_tx(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp, void *data)
 258 {
 259         u32 *arg = data;
 260         int i, ret;
 261         u32 xsr;
 262         u32 size, max_size, num_tr;
 263
 264         if (priv->dcfg->type & IMX_MU_V2_S4) {
 265                 size = ((struct imx_s4_rpc_msg_max *)data)->hdr.size;
 266                 max_size = sizeof(struct imx_s4_rpc_msg_max);
 267                 num_tr = 8;
 268         } else {
 269                 size = ((struct imx_sc_rpc_msg_max *)data)->hdr.size;
 270                 max_size = sizeof(struct imx_sc_rpc_msg_max);
 271                 num_tr = 4;
 272         }
 273
 274         switch (cp->type) {
 275         case IMX_MU_TYPE_TX:
 276                 /*
 277                  * msg->hdr.size specifies the number of u32 words while
 278                  * sizeof yields bytes.
 279                  */
 280
 281                 if (size > max_size / 4) {
 282                         /*
 283                          * The real message size can be different to
 284                          * struct imx_sc_rpc_msg_max/imx_s4_rpc_msg_max size
 285                          */
 286                         dev_err(priv->dev, "Maximal message size (%u bytes) exceeded on TX; got: %i bytes\n", max_size, size << 2);
 287                         return -EINVAL;
 288                 }
 289
 290                 for (i = 0; i < num_tr && i < size; i++)
 291                         imx_mu_write(priv, *arg++, priv->dcfg->xTR + (i % num_tr) * 4);
 292                 for (; i < size; i++) {
 293                         ret = readl_poll_timeout(priv->base + priv->dcfg->xSR[IMX_MU_TSR],
 294                                                  xsr,
 295                                                  xsr & IMX_MU_xSR_TEn(priv->dcfg->type, i % num_tr),
 296                                                  0, 5 * USEC_PER_SEC);
 297                         if (ret) {
 298                                 dev_err(priv->dev, "Send data index: %d timeout\n", i);
 299                                 return ret;
 300                         }
 301                         imx_mu_write(priv, *arg++, priv->dcfg->xTR + (i % num_tr) * 4);
 302                 }
 303
 304                 imx_mu_xcr_rmw(priv, IMX_MU_TCR, IMX_MU_xCR_TIEn(priv->dcfg->type, cp->idx), 0);
 305                 break;
 306         default:
 307                 dev_warn_ratelimited(priv->dev, "Send data on wrong channel type: %d\n", cp->type);
 308                 return -EINVAL;
 309         }
 310
 311         return 0;
 312 }
 313
 314 static int imx_mu_specific_rx(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp)
 315 {
 316         u32 *data;
 317         int i, ret;
 318         u32 xsr;
 319         u32 size, max_size;
 320
 321         data = (u32 *)priv->msg;
 322
 323         imx_mu_xcr_rmw(priv, IMX_MU_RCR, 0, IMX_MU_xCR_RIEn(priv->dcfg->type, 0));
 324         *data++ = imx_mu_read(priv, priv->dcfg->xRR);
 325
 326         if (priv->dcfg->type & IMX_MU_V2_S4) {
 327                 size = ((struct imx_s4_rpc_msg_max *)priv->msg)->hdr.size;
 328                 max_size = sizeof(struct imx_s4_rpc_msg_max);
 329         } else {
 330                 size = ((struct imx_sc_rpc_msg_max *)priv->msg)->hdr.size;
 331                 max_size = sizeof(struct imx_sc_rpc_msg_max);
 332         }
 333
 334         if (size > max_size / 4) {
 335                 dev_err(priv->dev, "Maximal message size (%u bytes) exceeded on RX; got: %i bytes\n", max_size, size << 2);
 336                 return -EINVAL;
 337         }
 338
 339         for (i = 1; i < size; i++) {
 340                 ret = readl_poll_timeout(priv->base + priv->dcfg->xSR[IMX_MU_RSR], xsr,
 341                                          xsr & IMX_MU_xSR_RFn(priv->dcfg->type, i % 4), 0,
 342                                          5 * USEC_PER_SEC);
 343                 if (ret) {
 344                         dev_err(priv->dev, "timeout read idx %d\n", i);
 345                         return ret;
 346                 }
 347                 *data++ = imx_mu_read(priv, priv->dcfg->xRR + (i % 4) * 4);
 348         }
 349
 350         imx_mu_xcr_rmw(priv, IMX_MU_RCR, IMX_MU_xCR_RIEn(priv->dcfg->type, 0), 0);
 351         mbox_chan_received_data(cp->chan, (void *)priv->msg);
 352
 353         return 0;
 354 }
 355
 356 static int imx_mu_seco_tx(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp,
 357                           void *data)
 358 {
 359         struct imx_sc_rpc_msg_max *msg = data;
 360         u32 *arg = data;
 361         u32 byte_size;
 362         int err;
 363         int i;
 364
 365         dev_dbg(priv->dev, "Sending message\n");
 366
 367         switch (cp->type) {
 368         case IMX_MU_TYPE_TXDB:
 369                 byte_size = msg->hdr.size * sizeof(u32);
 370                 if (byte_size > sizeof(*msg)) {
 371                         /*
 372                          * The real message size can be different to
 373                          * struct imx_sc_rpc_msg_max size
 374                          */
 375                         dev_err(priv->dev,
 376                                 "Exceed max msg size (%zu) on TX, got: %i\n",
 377                                 sizeof(*msg), byte_size);
 378                         return -EINVAL;
 379                 }
 380
 381                 print_hex_dump_debug("from client ", DUMP_PREFIX_OFFSET, 4, 4,
 382                                      data, byte_size, false);
 383
 384                 /* Send first word */
 385                 dev_dbg(priv->dev, "Sending header\n");
 386                 imx_mu_write(priv, *arg++, priv->dcfg->xTR);
 387
 388                 /* Send signaling */
 389                 dev_dbg(priv->dev, "Sending signaling\n");
 390                 imx_mu_xcr_rmw(priv, IMX_MU_GCR,
 391                                IMX_MU_xCR_GIRn(priv->dcfg->type, cp->idx), 0);
 392
 393                 /* Send words to fill the mailbox */
 394                 for (i = 1; i < 4 && i < msg->hdr.size; i++) {
 395                         dev_dbg(priv->dev, "Sending word %d\n", i);
 396                         imx_mu_write(priv, *arg++,
 397                                      priv->dcfg->xTR + (i % 4) * 4);
 398                 }
 399
 400                 /* Send rest of message waiting for remote read */
 401                 for (; i < msg->hdr.size; i++) {
 402                         dev_dbg(priv->dev, "Sending word %d\n", i);
 403                         err = imx_mu_tx_waiting_write(priv, *arg++, i);
 404                         if (err) {
 405                                 dev_err(priv->dev, "Timeout tx %d\n", i);
 406                                 return err;
 407                         }
 408                 }
 409
 410                 /* Simulate hack for mbox framework */
 411                 tasklet_schedule(&cp->txdb_tasklet);
 412
 413                 break;
 414         default:
 415                 dev_warn_ratelimited(priv->dev,
 416                                      "Send data on wrong channel type: %d\n",
 417                                      cp->type);
 418                 return -EINVAL;
 419         }
 420
 421         return 0;
 422 }
 423
 424 static int imx_mu_seco_rxdb(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp)
 425 {
 426         struct imx_sc_rpc_msg_max msg;
 427         u32 *data = (u32 *)&msg;
 428         u32 byte_size;
 429         int err = 0;
 430         int i;
 431
 432         dev_dbg(priv->dev, "Receiving message\n");
 433
 434         /* Read header */
 435         dev_dbg(priv->dev, "Receiving header\n");
 436         *data++ = imx_mu_read(priv, priv->dcfg->xRR);
 437         byte_size = msg.hdr.size * sizeof(u32);
 438         if (byte_size > sizeof(msg)) {
 439                 dev_err(priv->dev, "Exceed max msg size (%zu) on RX, got: %i\n",
 440                         sizeof(msg), byte_size);
 441                 err = -EINVAL;
 442                 goto error;
 443         }
 444
 445         /* Read message waiting they are written */
 446         for (i = 1; i < msg.hdr.size; i++) {
 447                 dev_dbg(priv->dev, "Receiving word %d\n", i);
 448                 err = imx_mu_rx_waiting_read(priv, data++, i);
 449                 if (err) {
 450                         dev_err(priv->dev, "Timeout rx %d\n", i);
 451                         goto error;
 452                 }
 453         }
 454
 455         /* Clear GIP */
 456         imx_mu_write(priv, IMX_MU_xSR_GIPn(priv->dcfg->type, cp->idx),
 457                      priv->dcfg->xSR[IMX_MU_GSR]);
 458
 459         print_hex_dump_debug("to client ", DUMP_PREFIX_OFFSET, 4, 4,
 460                              &msg, byte_size, false);
 461
 462         /* send data to client */
 463         dev_dbg(priv->dev, "Sending message to client\n");
 464         mbox_chan_received_data(cp->chan, (void *)&msg);
 465
 466         goto exit;
 467
 468 error:
 469         mbox_chan_received_data(cp->chan, ERR_PTR(err));
 470
 471 exit:
 472         return err;
 473 }
 474
 475 static void imx_mu_txdb_tasklet(unsigned long data)
 476 {
 477         struct imx_mu_con_priv *cp = (struct imx_mu_con_priv *)data;
 478
 479         mbox_chan_txdone(cp->chan, 0);
 480 }
 481
 482 static irqreturn_t imx_mu_isr(int irq, void *p)
 483 {
 484         struct mbox_chan *chan = p;
 485         struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
 486         struct imx_mu_con_priv *cp = chan->con_priv;
 487         u32 val, ctrl;
 488
 489         switch (cp->type) {
 490         case IMX_MU_TYPE_TX:
 491                 ctrl = imx_mu_read(priv, priv->dcfg->xCR[IMX_MU_TCR]);
 492                 val = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_TSR]);
 493                 val &= IMX_MU_xSR_TEn(priv->dcfg->type, cp->idx) &
 494                         (ctrl & IMX_MU_xCR_TIEn(priv->dcfg->type, cp->idx));
 495                 break;
 496         case IMX_MU_TYPE_RX:
 497                 ctrl = imx_mu_read(priv, priv->dcfg->xCR[IMX_MU_RCR]);
 498                 val = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_RSR]);
 499                 val &= IMX_MU_xSR_RFn(priv->dcfg->type, cp->idx) &
 500                         (ctrl & IMX_MU_xCR_RIEn(priv->dcfg->type, cp->idx));
 501                 break;
 502         case IMX_MU_TYPE_RXDB:
 503                 ctrl = imx_mu_read(priv, priv->dcfg->xCR[IMX_MU_GIER]);
 504                 val = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_GSR]);
 505                 val &= IMX_MU_xSR_GIPn(priv->dcfg->type, cp->idx) &
 506                         (ctrl & IMX_MU_xCR_GIEn(priv->dcfg->type, cp->idx));
 507                 break;
 508         case IMX_MU_TYPE_RST:
 509                 return IRQ_NONE;
 510         default:
 511                 dev_warn_ratelimited(priv->dev, "Unhandled channel type %d\n",
 512                                      cp->type);
 513                 return IRQ_NONE;
 514         }
 515
 516         if (!val)
 517                 return IRQ_NONE;
 518
 519         if ((val == IMX_MU_xSR_TEn(priv->dcfg->type, cp->idx)) &&
 520             (cp->type == IMX_MU_TYPE_TX)) {
 521                 imx_mu_xcr_rmw(priv, IMX_MU_TCR, 0, IMX_MU_xCR_TIEn(priv->dcfg->type, cp->idx));
 522                 mbox_chan_txdone(chan, 0);
 523         } else if ((val == IMX_MU_xSR_RFn(priv->dcfg->type, cp->idx)) &&
 524                    (cp->type == IMX_MU_TYPE_RX)) {
 525                 priv->dcfg->rx(priv, cp);
 526         } else if ((val == IMX_MU_xSR_GIPn(priv->dcfg->type, cp->idx)) &&
 527                    (cp->type == IMX_MU_TYPE_RXDB)) {
 528                 priv->dcfg->rxdb(priv, cp);
 529         } else {
 530                 dev_warn_ratelimited(priv->dev, "Not handled interrupt\n");
 531                 return IRQ_NONE;
 532         }
 533
 534         if (priv->suspend)
 535                 pm_system_wakeup();
 536
 537         return IRQ_HANDLED;
 538 }
 539
 540 static int imx_mu_send_data(struct mbox_chan *chan, void *data)
 541 {
 542         struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
 543         struct imx_mu_con_priv *cp = chan->con_priv;
 544
 545         return priv->dcfg->tx(priv, cp, data);
 546 }
 547
 548 static int imx_mu_startup(struct mbox_chan *chan)
 549 {
 550         struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
 551         struct imx_mu_con_priv *cp = chan->con_priv;
 552         unsigned long irq_flag = 0;
 553         int ret;
 554
 555         pm_runtime_get_sync(priv->dev);
 556         if (cp->type == IMX_MU_TYPE_TXDB) {
 557                 /* Tx doorbell don't have ACK support */
 558                 tasklet_init(&cp->txdb_tasklet, imx_mu_txdb_tasklet,
 559                              (unsigned long)cp);
 560                 return 0;
 561         }
 562
 563         /* IPC MU should be with IRQF_NO_SUSPEND set */
 564         if (!priv->dev->pm_domain)
 565                 irq_flag |= IRQF_NO_SUSPEND;
 566
 567         if (!(priv->dcfg->type & IMX_MU_V2_IRQ))
 568                 irq_flag |= IRQF_SHARED;
 569
 570         ret = request_irq(priv->irq[cp->type], imx_mu_isr, irq_flag, cp->irq_desc, chan);
 571         if (ret) {
 572                 dev_err(priv->dev, "Unable to acquire IRQ %d\n", priv->irq[cp->type]);
 573                 return ret;
 574         }
 575
 576         switch (cp->type) {
 577         case IMX_MU_TYPE_RX:
 578                 imx_mu_xcr_rmw(priv, IMX_MU_RCR, IMX_MU_xCR_RIEn(priv->dcfg->type, cp->idx), 0);
 579                 break;
 580         case IMX_MU_TYPE_RXDB:
 581                 imx_mu_xcr_rmw(priv, IMX_MU_GIER, IMX_MU_xCR_GIEn(priv->dcfg->type, cp->idx), 0);
 582                 break;
 583         default:
 584                 break;
 585         }
 586
 587         return 0;
 588 }
 589
 590 static void imx_mu_shutdown(struct mbox_chan *chan)
 591 {
 592         struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
 593         struct imx_mu_con_priv *cp = chan->con_priv;
 594         int ret;
 595         u32 sr;
 596
 597         if (cp->type == IMX_MU_TYPE_TXDB) {
 598                 tasklet_kill(&cp->txdb_tasklet);
 599                 pm_runtime_put_sync(priv->dev);
 600                 return;
 601         }
 602
 603         switch (cp->type) {
 604         case IMX_MU_TYPE_TX:
 605                 imx_mu_xcr_rmw(priv, IMX_MU_TCR, 0, IMX_MU_xCR_TIEn(priv->dcfg->type, cp->idx));
 606                 break;
 607         case IMX_MU_TYPE_RX:
 608                 imx_mu_xcr_rmw(priv, IMX_MU_RCR, 0, IMX_MU_xCR_RIEn(priv->dcfg->type, cp->idx));
 609                 break;
 610         case IMX_MU_TYPE_RXDB:
 611                 imx_mu_xcr_rmw(priv, IMX_MU_GIER, 0, IMX_MU_xCR_GIEn(priv->dcfg->type, cp->idx));
 612                 break;
 613         case IMX_MU_TYPE_RST:
 614                 imx_mu_xcr_rmw(priv, IMX_MU_CR, IMX_MU_xCR_RST(priv->dcfg->type), 0);
 615                 ret = readl_poll_timeout(priv->base + priv->dcfg->xSR[IMX_MU_SR], sr,
 616                                          !(sr & IMX_MU_xSR_RST(priv->dcfg->type)), 1, 5);
 617                 if (ret)
 618                         dev_warn(priv->dev, "RST channel timeout\n");
 619                 break;
 620         default:
 621                 break;
 622         }
 623
 624         free_irq(priv->irq[cp->type], chan);
 625         pm_runtime_put_sync(priv->dev);
 626 }
 627
 628 static const struct mbox_chan_ops imx_mu_ops = {
 629         .send_data = imx_mu_send_data,
 630         .startup = imx_mu_startup,
 631         .shutdown = imx_mu_shutdown,
 632 };
 633
 634 static struct mbox_chan *imx_mu_specific_xlate(struct mbox_controller *mbox,
 635                                                const struct of_phandle_args *sp)
 636 {
 637         u32 type, idx, chan;
 638
 639         if (sp->args_count != 2) {
 640                 dev_err(mbox->dev, "Invalid argument count %d\n", sp->args_count);
 641                 return ERR_PTR(-EINVAL);
 642         }
 643
 644         type = sp->args[0]; /* channel type */
 645         idx = sp->args[1]; /* index */
 646
 647         switch (type) {
 648         case IMX_MU_TYPE_TX:
 649         case IMX_MU_TYPE_RX:
 650                 if (idx != 0)
 651                         dev_err(mbox->dev, "Invalid chan idx: %d\n", idx);
 652                 chan = type;
 653                 break;
 654         case IMX_MU_TYPE_RXDB:
 655                 chan = 2 + idx;
 656                 break;
 657         default:
 658                 dev_err(mbox->dev, "Invalid chan type: %d\n", type);
 659                 return ERR_PTR(-EINVAL);
 660         }
 661
 662         if (chan >= mbox->num_chans) {
 663                 dev_err(mbox->dev, "Not supported channel number: %d. (type: %d, idx: %d)\n", chan, type, idx);
 664                 return ERR_PTR(-EINVAL);
 665         }
 666
 667         return &mbox->chans[chan];
 668 }
 669
 670 static struct mbox_chan * imx_mu_xlate(struct mbox_controller *mbox,
 671                                        const struct of_phandle_args *sp)
 672 {
 673         u32 type, idx, chan;
 674
 675         if (sp->args_count != 2) {
 676                 dev_err(mbox->dev, "Invalid argument count %d\n", sp->args_count);
 677                 return ERR_PTR(-EINVAL);
 678         }
 679
 680         type = sp->args[0]; /* channel type */
 681         idx = sp->args[1]; /* index */
 682         chan = type * 4 + idx;
 683
 684         if (chan >= mbox->num_chans) {
 685                 dev_err(mbox->dev, "Not supported channel number: %d. (type: %d, idx: %d)\n", chan, type, idx);
 686                 return ERR_PTR(-EINVAL);
 687         }
 688
 689         return &mbox->chans[chan];
 690 }
 691
 692 static struct mbox_chan *imx_mu_seco_xlate(struct mbox_controller *mbox,
 693                                            const struct of_phandle_args *sp)
 694 {
 695         u32 type;
 696
 697         if (sp->args_count < 1) {
 698                 dev_err(mbox->dev, "Invalid argument count %d\n", sp->args_count);
 699                 return ERR_PTR(-EINVAL);
 700         }
 701
 702         type = sp->args[0]; /* channel type */
 703
 704         /* Only supports TXDB and RXDB */
 705         if (type == IMX_MU_TYPE_TX || type == IMX_MU_TYPE_RX) {
 706                 dev_err(mbox->dev, "Invalid type: %d\n", type);
 707                 return ERR_PTR(-EINVAL);
 708         }
 709
 710         return imx_mu_xlate(mbox, sp);
 711 }
 712
 713 static void imx_mu_init_generic(struct imx_mu_priv *priv)
 714 {
 715         unsigned int i;
 716         unsigned int val;
 717
 718         for (i = 0; i < IMX_MU_CHANS; i++) {
 719                 struct imx_mu_con_priv *cp = &priv->con_priv[i];
 720
 721                 cp->idx = i % 4;
 722                 cp->type = i >> 2;
 723                 cp->chan = &priv->mbox_chans[i];
 724                 priv->mbox_chans[i].con_priv = cp;
 725                 snprintf(cp->irq_desc, sizeof(cp->irq_desc),
 726                          "imx_mu_chan[%i-%i]", cp->type, cp->idx);
 727         }
 728
 729         priv->mbox.num_chans = IMX_MU_CHANS;
 730         priv->mbox.of_xlate = imx_mu_xlate;
 731
 732         if (priv->side_b)
 733                 return;
 734
 735         /* Set default MU configuration */
 736         for (i = 0; i < IMX_MU_xCR_MAX; i++)
 737                 imx_mu_write(priv, 0, priv->dcfg->xCR[i]);
 738
 739         /* Clear any pending GIP */
 740         val = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_GSR]);
 741         imx_mu_write(priv, val, priv->dcfg->xSR[IMX_MU_GSR]);
 742
 743         /* Clear any pending RSR */
 744         for (i = 0; i < IMX_MU_NUM_RR; i++)
 745                 imx_mu_read(priv, priv->dcfg->xRR + (i % 4) * 4);
 746 }
 747
 748 static void imx_mu_init_specific(struct imx_mu_priv *priv)
 749 {
 750         unsigned int i;
 751         int num_chans = priv->dcfg->type & IMX_MU_V2_S4 ? IMX_MU_S4_CHANS : IMX_MU_SCU_CHANS;
 752
 753         for (i = 0; i < num_chans; i++) {
 754                 struct imx_mu_con_priv *cp = &priv->con_priv[i];
 755
 756                 cp->idx = i < 2 ? 0 : i - 2;
 757                 cp->type = i < 2 ? i : IMX_MU_TYPE_RXDB;
 758                 cp->chan = &priv->mbox_chans[i];
 759                 priv->mbox_chans[i].con_priv = cp;
 760                 snprintf(cp->irq_desc, sizeof(cp->irq_desc),
 761                          "imx_mu_chan[%i-%i]", cp->type, cp->idx);
 762         }
 763
 764         priv->mbox.num_chans = num_chans;
 765         priv->mbox.of_xlate = imx_mu_specific_xlate;
 766
 767         /* Set default MU configuration */
 768         for (i = 0; i < IMX_MU_xCR_MAX; i++)
 769                 imx_mu_write(priv, 0, priv->dcfg->xCR[i]);
 770 }
 771
 772 static void imx_mu_init_seco(struct imx_mu_priv *priv)
 773 {
 774         imx_mu_init_generic(priv);
 775         priv->mbox.of_xlate = imx_mu_seco_xlate;
 776 }
 777
 778 static int imx_mu_probe(struct platform_device *pdev)
 779 {
 780         struct device *dev = &pdev->dev;
 781         struct device_node *np = dev->of_node;
 782         struct imx_mu_priv *priv;
 783         const struct imx_mu_dcfg *dcfg;
 784         int i, ret;
 785         u32 size;
 786
 787         priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 788         if (!priv)
 789                 return -ENOMEM;
 790
 791         priv->dev = dev;
 792
 793         priv->base = devm_platform_ioremap_resource(pdev, 0);
 794         if (IS_ERR(priv->base))
 795                 return PTR_ERR(priv->base);
 796
 797         dcfg = of_device_get_match_data(dev);
 798         if (!dcfg)
 799                 return -EINVAL;
 800         priv->dcfg = dcfg;
 801         if (priv->dcfg->type & IMX_MU_V2_IRQ) {
 802                 priv->irq[IMX_MU_TYPE_TX] = platform_get_irq_byname(pdev, "tx");
 803                 if (priv->irq[IMX_MU_TYPE_TX] < 0)
 804                         return priv->irq[IMX_MU_TYPE_TX];
 805                 priv->irq[IMX_MU_TYPE_RX] = platform_get_irq_byname(pdev, "rx");
 806                 if (priv->irq[IMX_MU_TYPE_RX] < 0)
 807                         return priv->irq[IMX_MU_TYPE_RX];
 808         } else {
 809                 ret = platform_get_irq(pdev, 0);
 810                 if (ret < 0)
 811                         return ret;
 812
 813                 for (i = 0; i < IMX_MU_CHANS; i++)
 814                         priv->irq[i] = ret;
 815         }
 816
 817         if (priv->dcfg->type & IMX_MU_V2_S4)
 818                 size = sizeof(struct imx_s4_rpc_msg_max);
 819         else
 820                 size = sizeof(struct imx_sc_rpc_msg_max);
 821
 822         priv->msg = devm_kzalloc(dev, size, GFP_KERNEL);
 823         if (!priv->msg)
 824                 return -ENOMEM;
 825
 826         priv->clk = devm_clk_get(dev, NULL);
 827         if (IS_ERR(priv->clk)) {
 828                 if (PTR_ERR(priv->clk) != -ENOENT)
 829                         return PTR_ERR(priv->clk);
 830
 831                 priv->clk = NULL;
 832         }
 833
 834         ret = clk_prepare_enable(priv->clk);
 835         if (ret) {
 836                 dev_err(dev, "Failed to enable clock\n");
 837                 return ret;
 838         }
 839
 840         priv->side_b = of_property_read_bool(np, "fsl,mu-side-b");
 841
 842         priv->dcfg->init(priv);
 843
 844         spin_lock_init(&priv->xcr_lock);
 845
 846         priv->mbox.dev = dev;
 847         priv->mbox.ops = &imx_mu_ops;
 848         priv->mbox.chans = priv->mbox_chans;
 849         priv->mbox.txdone_irq = true;
 850
 851         platform_set_drvdata(pdev, priv);
 852
 853         ret = devm_mbox_controller_register(dev, &priv->mbox);
 854         if (ret) {
 855                 clk_disable_unprepare(priv->clk);
 856                 return ret;
 857         }
 858
 859         pm_runtime_enable(dev);
 860
 861         ret = pm_runtime_resume_and_get(dev);
 862         if (ret < 0)
 863                 goto disable_runtime_pm;
 864
 865         ret = pm_runtime_put_sync(dev);
 866         if (ret < 0)
 867                 goto disable_runtime_pm;
 868
 869         clk_disable_unprepare(priv->clk);
 870
 871         return 0;
 872
 873 disable_runtime_pm:
 874         pm_runtime_disable(dev);
 875         clk_disable_unprepare(priv->clk);
 876         return ret;
 877 }
 878
 879 static int imx_mu_remove(struct platform_device *pdev)
 880 {
 881         struct imx_mu_priv *priv = platform_get_drvdata(pdev);
 882
 883         pm_runtime_disable(priv->dev);
 884
 885         return 0;
 886 }
 887
 888 static const struct imx_mu_dcfg imx_mu_cfg_imx6sx = {
 889         .tx     = imx_mu_generic_tx,
 890         .rx     = imx_mu_generic_rx,
 891         .rxdb   = imx_mu_generic_rxdb,
 892         .init   = imx_mu_init_generic,
 893         .xTR    = 0x0,
 894         .xRR    = 0x10,
 895         .xSR    = {0x20, 0x20, 0x20, 0x20},
 896         .xCR    = {0x24, 0x24, 0x24, 0x24, 0x24},
 897 };
 898
 899 static const struct imx_mu_dcfg imx_mu_cfg_imx7ulp = {
 900         .tx     = imx_mu_generic_tx,
 901         .rx     = imx_mu_generic_rx,
 902         .rxdb   = imx_mu_generic_rxdb,
 903         .init   = imx_mu_init_generic,
 904         .xTR    = 0x20,
 905         .xRR    = 0x40,
 906         .xSR    = {0x60, 0x60, 0x60, 0x60},
 907         .xCR    = {0x64, 0x64, 0x64, 0x64},
 908 };
 909
 910 static const struct imx_mu_dcfg imx_mu_cfg_imx8ulp = {
 911         .tx     = imx_mu_generic_tx,
 912         .rx     = imx_mu_generic_rx,
 913         .rxdb   = imx_mu_generic_rxdb,
 914         .init   = imx_mu_init_generic,
 915         .type   = IMX_MU_V2,
 916         .xTR    = 0x200,
 917         .xRR    = 0x280,
 918         .xSR    = {0xC, 0x118, 0x124, 0x12C},
 919         .xCR    = {0x8, 0x110, 0x114, 0x120, 0x128},
 920 };
 921
 922 static const struct imx_mu_dcfg imx_mu_cfg_imx8ulp_s4 = {
 923         .tx     = imx_mu_specific_tx,
 924         .rx     = imx_mu_specific_rx,
 925         .init   = imx_mu_init_specific,
 926         .type   = IMX_MU_V2 | IMX_MU_V2_S4,
 927         .xTR    = 0x200,
 928         .xRR    = 0x280,
 929         .xSR    = {0xC, 0x118, 0x124, 0x12C},
 930         .xCR    = {0x110, 0x114, 0x120, 0x128},
 931 };
 932
 933 static const struct imx_mu_dcfg imx_mu_cfg_imx93_s4 = {
 934         .tx     = imx_mu_specific_tx,
 935         .rx     = imx_mu_specific_rx,
 936         .init   = imx_mu_init_specific,
 937         .type   = IMX_MU_V2 | IMX_MU_V2_S4 | IMX_MU_V2_IRQ,
 938         .xTR    = 0x200,
 939         .xRR    = 0x280,
 940         .xSR    = {0xC, 0x118, 0x124, 0x12C},
 941         .xCR    = {0x110, 0x114, 0x120, 0x128},
 942 };
 943
 944 static const struct imx_mu_dcfg imx_mu_cfg_imx8_scu = {
 945         .tx     = imx_mu_specific_tx,
 946         .rx     = imx_mu_specific_rx,
 947         .init   = imx_mu_init_specific,
 948         .rxdb   = imx_mu_generic_rxdb,
 949         .xTR    = 0x0,
 950         .xRR    = 0x10,
 951         .xSR    = {0x20, 0x20, 0x20, 0x20},
 952         .xCR    = {0x24, 0x24, 0x24, 0x24},
 953 };
 954
 955 static const struct imx_mu_dcfg imx_mu_cfg_imx8_seco = {
 956         .tx     = imx_mu_seco_tx,
 957         .rx     = imx_mu_generic_rx,
 958         .rxdb   = imx_mu_seco_rxdb,
 959         .init   = imx_mu_init_seco,
 960         .xTR    = 0x0,
 961         .xRR    = 0x10,
 962         .xSR    = {0x20, 0x20, 0x20, 0x20},
 963         .xCR    = {0x24, 0x24, 0x24, 0x24},
 964 };
 965
 966 static const struct of_device_id imx_mu_dt_ids[] = {
 967         { .compatible = "fsl,imx7ulp-mu", .data = &imx_mu_cfg_imx7ulp },
 968         { .compatible = "fsl,imx6sx-mu", .data = &imx_mu_cfg_imx6sx },
 969         { .compatible = "fsl,imx8ulp-mu", .data = &imx_mu_cfg_imx8ulp },
 970         { .compatible = "fsl,imx8ulp-mu-s4", .data = &imx_mu_cfg_imx8ulp_s4 },
 971         { .compatible = "fsl,imx93-mu-s4", .data = &imx_mu_cfg_imx93_s4 },
 972         { .compatible = "fsl,imx8-mu-scu", .data = &imx_mu_cfg_imx8_scu },
 973         { .compatible = "fsl,imx8-mu-seco", .data = &imx_mu_cfg_imx8_seco },
 974         { },
 975 };
 976 MODULE_DEVICE_TABLE(of, imx_mu_dt_ids);
 977
 978 static int __maybe_unused imx_mu_suspend_noirq(struct device *dev)
 979 {
 980         struct imx_mu_priv *priv = dev_get_drvdata(dev);
 981         int i;
 982
 983         if (!priv->clk) {
 984                 for (i = 0; i < IMX_MU_xCR_MAX; i++)
 985                         priv->xcr[i] = imx_mu_read(priv, priv->dcfg->xCR[i]);
 986         }
 987
 988         priv->suspend = true;
 989
 990         return 0;
 991 }
 992
 993 static int __maybe_unused imx_mu_resume_noirq(struct device *dev)
 994 {
 995         struct imx_mu_priv *priv = dev_get_drvdata(dev);
 996         int i;
 997
 998         /*
 999          * ONLY restore MU when context lost, the TIE could
1000          * be set during noirq resume as there is MU data
1001          * communication going on, and restore the saved
1002          * value will overwrite the TIE and cause MU data
1003          * send failed, may lead to system freeze. This issue
1004          * is observed by testing freeze mode suspend.
1005          */
1006         if (!priv->clk && !imx_mu_read(priv, priv->dcfg->xCR[0])) {
1007                 for (i = 0; i < IMX_MU_xCR_MAX; i++)
1008                         imx_mu_write(priv, priv->xcr[i], priv->dcfg->xCR[i]);
1009         }
1010
1011         priv->suspend = false;
1012
1013         return 0;
1014 }
1015
1016 static int __maybe_unused imx_mu_runtime_suspend(struct device *dev)
1017 {
1018         struct imx_mu_priv *priv = dev_get_drvdata(dev);
1019
1020         clk_disable_unprepare(priv->clk);
1021
1022         return 0;
1023 }
1024
1025 static int __maybe_unused imx_mu_runtime_resume(struct device *dev)
1026 {
1027         struct imx_mu_priv *priv = dev_get_drvdata(dev);
1028         int ret;
1029
1030         ret = clk_prepare_enable(priv->clk);
1031         if (ret)
1032                 dev_err(dev, "failed to enable clock\n");
1033
1034         return ret;
1035 }
1036
1037 static const struct dev_pm_ops imx_mu_pm_ops = {
1038         SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx_mu_suspend_noirq,
1039                                       imx_mu_resume_noirq)
1040         SET_RUNTIME_PM_OPS(imx_mu_runtime_suspend,
1041                            imx_mu_runtime_resume, NULL)
1042 };
1043
1044 static struct platform_driver imx_mu_driver = {
1045         .probe          = imx_mu_probe,
1046         .remove         = imx_mu_remove,
1047         .driver = {
1048                 .name   = "imx_mu",
1049                 .of_match_table = imx_mu_dt_ids,
1050                 .pm = &imx_mu_pm_ops,
1051         },
1052 };
1053 module_platform_driver(imx_mu_driver);
1054
1055 MODULE_AUTHOR("Oleksij Rempel <o.rempel@pengutronix.de>");
1056 MODULE_DESCRIPTION("Message Unit driver for i.MX");
1057 MODULE_LICENSE("GPL v2");