linux/drivers/staging/mt7621-dma/hsdma-mt7621.c
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   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 *  Copyright (C) 2015, Michael Lee <igvtee@gmail.com>
   4 *  MTK HSDMA support
   5 */
   6
   7#include <linux/dmaengine.h>
   8#include <linux/dma-mapping.h>
   9#include <linux/err.h>
  10#include <linux/init.h>
  11#include <linux/list.h>
  12#include <linux/module.h>
  13#include <linux/platform_device.h>
  14#include <linux/slab.h>
  15#include <linux/spinlock.h>
  16#include <linux/irq.h>
  17#include <linux/of_dma.h>
  18#include <linux/reset.h>
  19#include <linux/of_device.h>
  20
  21#include "virt-dma.h"
  22
  23#define HSDMA_BASE_OFFSET               0x800
  24
  25#define HSDMA_REG_TX_BASE               0x00
  26#define HSDMA_REG_TX_CNT                0x04
  27#define HSDMA_REG_TX_CTX                0x08
  28#define HSDMA_REG_TX_DTX                0x0c
  29#define HSDMA_REG_RX_BASE               0x100
  30#define HSDMA_REG_RX_CNT                0x104
  31#define HSDMA_REG_RX_CRX                0x108
  32#define HSDMA_REG_RX_DRX                0x10c
  33#define HSDMA_REG_INFO                  0x200
  34#define HSDMA_REG_GLO_CFG               0x204
  35#define HSDMA_REG_RST_CFG               0x208
  36#define HSDMA_REG_DELAY_INT             0x20c
  37#define HSDMA_REG_FREEQ_THRES           0x210
  38#define HSDMA_REG_INT_STATUS            0x220
  39#define HSDMA_REG_INT_MASK              0x228
  40#define HSDMA_REG_SCH_Q01               0x280
  41#define HSDMA_REG_SCH_Q23               0x284
  42
  43#define HSDMA_DESCS_MAX                 0xfff
  44#define HSDMA_DESCS_NUM                 8
  45#define HSDMA_DESCS_MASK                (HSDMA_DESCS_NUM - 1)
  46#define HSDMA_NEXT_DESC(x)              (((x) + 1) & HSDMA_DESCS_MASK)
  47
  48/* HSDMA_REG_INFO */
  49#define HSDMA_INFO_INDEX_MASK           0xf
  50#define HSDMA_INFO_INDEX_SHIFT          24
  51#define HSDMA_INFO_BASE_MASK            0xff
  52#define HSDMA_INFO_BASE_SHIFT           16
  53#define HSDMA_INFO_RX_MASK              0xff
  54#define HSDMA_INFO_RX_SHIFT             8
  55#define HSDMA_INFO_TX_MASK              0xff
  56#define HSDMA_INFO_TX_SHIFT             0
  57
  58/* HSDMA_REG_GLO_CFG */
  59#define HSDMA_GLO_TX_2B_OFFSET          BIT(31)
  60#define HSDMA_GLO_CLK_GATE              BIT(30)
  61#define HSDMA_GLO_BYTE_SWAP             BIT(29)
  62#define HSDMA_GLO_MULTI_DMA             BIT(10)
  63#define HSDMA_GLO_TWO_BUF               BIT(9)
  64#define HSDMA_GLO_32B_DESC              BIT(8)
  65#define HSDMA_GLO_BIG_ENDIAN            BIT(7)
  66#define HSDMA_GLO_TX_DONE               BIT(6)
  67#define HSDMA_GLO_BT_MASK               0x3
  68#define HSDMA_GLO_BT_SHIFT              4
  69#define HSDMA_GLO_RX_BUSY               BIT(3)
  70#define HSDMA_GLO_RX_DMA                BIT(2)
  71#define HSDMA_GLO_TX_BUSY               BIT(1)
  72#define HSDMA_GLO_TX_DMA                BIT(0)
  73
  74#define HSDMA_BT_SIZE_16BYTES           (0 << HSDMA_GLO_BT_SHIFT)
  75#define HSDMA_BT_SIZE_32BYTES           (1 << HSDMA_GLO_BT_SHIFT)
  76#define HSDMA_BT_SIZE_64BYTES           (2 << HSDMA_GLO_BT_SHIFT)
  77#define HSDMA_BT_SIZE_128BYTES          (3 << HSDMA_GLO_BT_SHIFT)
  78
  79#define HSDMA_GLO_DEFAULT               (HSDMA_GLO_MULTI_DMA | \
  80                HSDMA_GLO_RX_DMA | HSDMA_GLO_TX_DMA | HSDMA_BT_SIZE_32BYTES)
  81
  82/* HSDMA_REG_RST_CFG */
  83#define HSDMA_RST_RX_SHIFT              16
  84#define HSDMA_RST_TX_SHIFT              0
  85
  86/* HSDMA_REG_DELAY_INT */
  87#define HSDMA_DELAY_INT_EN              BIT(15)
  88#define HSDMA_DELAY_PEND_OFFSET         8
  89#define HSDMA_DELAY_TIME_OFFSET         0
  90#define HSDMA_DELAY_TX_OFFSET           16
  91#define HSDMA_DELAY_RX_OFFSET           0
  92
  93#define HSDMA_DELAY_INIT(x)             (HSDMA_DELAY_INT_EN | \
  94                ((x) << HSDMA_DELAY_PEND_OFFSET))
  95#define HSDMA_DELAY(x)                  ((HSDMA_DELAY_INIT(x) << \
  96                HSDMA_DELAY_TX_OFFSET) | HSDMA_DELAY_INIT(x))
  97
  98/* HSDMA_REG_INT_STATUS */
  99#define HSDMA_INT_DELAY_RX_COH          BIT(31)
 100#define HSDMA_INT_DELAY_RX_INT          BIT(30)
 101#define HSDMA_INT_DELAY_TX_COH          BIT(29)
 102#define HSDMA_INT_DELAY_TX_INT          BIT(28)
 103#define HSDMA_INT_RX_MASK               0x3
 104#define HSDMA_INT_RX_SHIFT              16
 105#define HSDMA_INT_RX_Q0                 BIT(16)
 106#define HSDMA_INT_TX_MASK               0xf
 107#define HSDMA_INT_TX_SHIFT              0
 108#define HSDMA_INT_TX_Q0                 BIT(0)
 109
 110/* tx/rx dma desc flags */
 111#define HSDMA_PLEN_MASK                 0x3fff
 112#define HSDMA_DESC_DONE                 BIT(31)
 113#define HSDMA_DESC_LS0                  BIT(30)
 114#define HSDMA_DESC_PLEN0(_x)            (((_x) & HSDMA_PLEN_MASK) << 16)
 115#define HSDMA_DESC_TAG                  BIT(15)
 116#define HSDMA_DESC_LS1                  BIT(14)
 117#define HSDMA_DESC_PLEN1(_x)            ((_x) & HSDMA_PLEN_MASK)
 118
 119/* align 4 bytes */
 120#define HSDMA_ALIGN_SIZE                3
 121/* align size 128bytes */
 122#define HSDMA_MAX_PLEN                  0x3f80
 123
 124struct hsdma_desc {
 125        u32 addr0;
 126        u32 flags;
 127        u32 addr1;
 128        u32 unused;
 129};
 130
 131struct mtk_hsdma_sg {
 132        dma_addr_t src_addr;
 133        dma_addr_t dst_addr;
 134        u32 len;
 135};
 136
 137struct mtk_hsdma_desc {
 138        struct virt_dma_desc vdesc;
 139        unsigned int num_sgs;
 140        struct mtk_hsdma_sg sg[1];
 141};
 142
 143struct mtk_hsdma_chan {
 144        struct virt_dma_chan vchan;
 145        unsigned int id;
 146        dma_addr_t desc_addr;
 147        int tx_idx;
 148        int rx_idx;
 149        struct hsdma_desc *tx_ring;
 150        struct hsdma_desc *rx_ring;
 151        struct mtk_hsdma_desc *desc;
 152        unsigned int next_sg;
 153};
 154
 155struct mtk_hsdam_engine {
 156        struct dma_device ddev;
 157        struct device_dma_parameters dma_parms;
 158        void __iomem *base;
 159        struct tasklet_struct task;
 160        volatile unsigned long chan_issued;
 161
 162        struct mtk_hsdma_chan chan[1];
 163};
 164
 165static inline struct mtk_hsdam_engine *mtk_hsdma_chan_get_dev(
 166                struct mtk_hsdma_chan *chan)
 167{
 168        return container_of(chan->vchan.chan.device, struct mtk_hsdam_engine,
 169                        ddev);
 170}
 171
 172static inline struct mtk_hsdma_chan *to_mtk_hsdma_chan(struct dma_chan *c)
 173{
 174        return container_of(c, struct mtk_hsdma_chan, vchan.chan);
 175}
 176
 177static inline struct mtk_hsdma_desc *to_mtk_hsdma_desc(
 178                struct virt_dma_desc *vdesc)
 179{
 180        return container_of(vdesc, struct mtk_hsdma_desc, vdesc);
 181}
 182
 183static inline u32 mtk_hsdma_read(struct mtk_hsdam_engine *hsdma, u32 reg)
 184{
 185        return readl(hsdma->base + reg);
 186}
 187
 188static inline void mtk_hsdma_write(struct mtk_hsdam_engine *hsdma,
 189                                   unsigned int reg, u32 val)
 190{
 191        writel(val, hsdma->base + reg);
 192}
 193
 194static void mtk_hsdma_reset_chan(struct mtk_hsdam_engine *hsdma,
 195                                 struct mtk_hsdma_chan *chan)
 196{
 197        chan->tx_idx = 0;
 198        chan->rx_idx = HSDMA_DESCS_NUM - 1;
 199
 200        mtk_hsdma_write(hsdma, HSDMA_REG_TX_CTX, chan->tx_idx);
 201        mtk_hsdma_write(hsdma, HSDMA_REG_RX_CRX, chan->rx_idx);
 202
 203        mtk_hsdma_write(hsdma, HSDMA_REG_RST_CFG,
 204                        0x1 << (chan->id + HSDMA_RST_TX_SHIFT));
 205        mtk_hsdma_write(hsdma, HSDMA_REG_RST_CFG,
 206                        0x1 << (chan->id + HSDMA_RST_RX_SHIFT));
 207}
 208
 209static void hsdma_dump_reg(struct mtk_hsdam_engine *hsdma)
 210{
 211        dev_dbg(hsdma->ddev.dev,
 212                "tbase %08x, tcnt %08x, tctx %08x, tdtx: %08x, rbase %08x, rcnt %08x, rctx %08x, rdtx %08x\n",
 213                mtk_hsdma_read(hsdma, HSDMA_REG_TX_BASE),
 214                mtk_hsdma_read(hsdma, HSDMA_REG_TX_CNT),
 215                mtk_hsdma_read(hsdma, HSDMA_REG_TX_CTX),
 216                mtk_hsdma_read(hsdma, HSDMA_REG_TX_DTX),
 217                mtk_hsdma_read(hsdma, HSDMA_REG_RX_BASE),
 218                mtk_hsdma_read(hsdma, HSDMA_REG_RX_CNT),
 219                mtk_hsdma_read(hsdma, HSDMA_REG_RX_CRX),
 220                mtk_hsdma_read(hsdma, HSDMA_REG_RX_DRX));
 221
 222        dev_dbg(hsdma->ddev.dev,
 223                "info %08x, glo %08x, delay %08x, intr_stat %08x, intr_mask %08x\n",
 224                mtk_hsdma_read(hsdma, HSDMA_REG_INFO),
 225                mtk_hsdma_read(hsdma, HSDMA_REG_GLO_CFG),
 226                mtk_hsdma_read(hsdma, HSDMA_REG_DELAY_INT),
 227                mtk_hsdma_read(hsdma, HSDMA_REG_INT_STATUS),
 228                mtk_hsdma_read(hsdma, HSDMA_REG_INT_MASK));
 229}
 230
 231static void hsdma_dump_desc(struct mtk_hsdam_engine *hsdma,
 232                            struct mtk_hsdma_chan *chan)
 233{
 234        struct hsdma_desc *tx_desc;
 235        struct hsdma_desc *rx_desc;
 236        int i;
 237
 238        dev_dbg(hsdma->ddev.dev, "tx idx: %d, rx idx: %d\n",
 239                chan->tx_idx, chan->rx_idx);
 240
 241        for (i = 0; i < HSDMA_DESCS_NUM; i++) {
 242                tx_desc = &chan->tx_ring[i];
 243                rx_desc = &chan->rx_ring[i];
 244
 245                dev_dbg(hsdma->ddev.dev,
 246                        "%d tx addr0: %08x, flags %08x, tx addr1: %08x, rx addr0 %08x, flags %08x\n",
 247                        i, tx_desc->addr0, tx_desc->flags,
 248                        tx_desc->addr1, rx_desc->addr0, rx_desc->flags);
 249        }
 250}
 251
 252static void mtk_hsdma_reset(struct mtk_hsdam_engine *hsdma,
 253                            struct mtk_hsdma_chan *chan)
 254{
 255        int i;
 256
 257        /* disable dma */
 258        mtk_hsdma_write(hsdma, HSDMA_REG_GLO_CFG, 0);
 259
 260        /* disable intr */
 261        mtk_hsdma_write(hsdma, HSDMA_REG_INT_MASK, 0);
 262
 263        /* init desc value */
 264        for (i = 0; i < HSDMA_DESCS_NUM; i++) {
 265                chan->tx_ring[i].addr0 = 0;
 266                chan->tx_ring[i].flags = HSDMA_DESC_LS0 | HSDMA_DESC_DONE;
 267        }
 268        for (i = 0; i < HSDMA_DESCS_NUM; i++) {
 269                chan->rx_ring[i].addr0 = 0;
 270                chan->rx_ring[i].flags = 0;
 271        }
 272
 273        /* reset */
 274        mtk_hsdma_reset_chan(hsdma, chan);
 275
 276        /* enable intr */
 277        mtk_hsdma_write(hsdma, HSDMA_REG_INT_MASK, HSDMA_INT_RX_Q0);
 278
 279        /* enable dma */
 280        mtk_hsdma_write(hsdma, HSDMA_REG_GLO_CFG, HSDMA_GLO_DEFAULT);
 281}
 282
 283static int mtk_hsdma_terminate_all(struct dma_chan *c)
 284{
 285        struct mtk_hsdma_chan *chan = to_mtk_hsdma_chan(c);
 286        struct mtk_hsdam_engine *hsdma = mtk_hsdma_chan_get_dev(chan);
 287        unsigned long timeout;
 288        LIST_HEAD(head);
 289
 290        spin_lock_bh(&chan->vchan.lock);
 291        chan->desc = NULL;
 292        clear_bit(chan->id, &hsdma->chan_issued);
 293        vchan_get_all_descriptors(&chan->vchan, &head);
 294        spin_unlock_bh(&chan->vchan.lock);
 295
 296        vchan_dma_desc_free_list(&chan->vchan, &head);
 297
 298        /* wait dma transfer complete */
 299        timeout = jiffies + msecs_to_jiffies(2000);
 300        while (mtk_hsdma_read(hsdma, HSDMA_REG_GLO_CFG) &
 301                        (HSDMA_GLO_RX_BUSY | HSDMA_GLO_TX_BUSY)) {
 302                if (time_after_eq(jiffies, timeout)) {
 303                        hsdma_dump_desc(hsdma, chan);
 304                        mtk_hsdma_reset(hsdma, chan);
 305                        dev_err(hsdma->ddev.dev, "timeout, reset it\n");
 306                        break;
 307                }
 308                cpu_relax();
 309        }
 310
 311        return 0;
 312}
 313
 314static int mtk_hsdma_start_transfer(struct mtk_hsdam_engine *hsdma,
 315                                    struct mtk_hsdma_chan *chan)
 316{
 317        dma_addr_t src, dst;
 318        size_t len, tlen;
 319        struct hsdma_desc *tx_desc, *rx_desc;
 320        struct mtk_hsdma_sg *sg;
 321        unsigned int i;
 322        int rx_idx;
 323
 324        sg = &chan->desc->sg[0];
 325        len = sg->len;
 326        chan->desc->num_sgs = DIV_ROUND_UP(len, HSDMA_MAX_PLEN);
 327
 328        /* tx desc */
 329        src = sg->src_addr;
 330        for (i = 0; i < chan->desc->num_sgs; i++) {
 331                tx_desc = &chan->tx_ring[chan->tx_idx];
 332
 333                if (len > HSDMA_MAX_PLEN)
 334                        tlen = HSDMA_MAX_PLEN;
 335                else
 336                        tlen = len;
 337
 338                if (i & 0x1) {
 339                        tx_desc->addr1 = src;
 340                        tx_desc->flags |= HSDMA_DESC_PLEN1(tlen);
 341                } else {
 342                        tx_desc->addr0 = src;
 343                        tx_desc->flags = HSDMA_DESC_PLEN0(tlen);
 344
 345                        /* update index */
 346                        chan->tx_idx = HSDMA_NEXT_DESC(chan->tx_idx);
 347                }
 348
 349                src += tlen;
 350                len -= tlen;
 351        }
 352        if (i & 0x1)
 353                tx_desc->flags |= HSDMA_DESC_LS0;
 354        else
 355                tx_desc->flags |= HSDMA_DESC_LS1;
 356
 357        /* rx desc */
 358        rx_idx = HSDMA_NEXT_DESC(chan->rx_idx);
 359        len = sg->len;
 360        dst = sg->dst_addr;
 361        for (i = 0; i < chan->desc->num_sgs; i++) {
 362                rx_desc = &chan->rx_ring[rx_idx];
 363                if (len > HSDMA_MAX_PLEN)
 364                        tlen = HSDMA_MAX_PLEN;
 365                else
 366                        tlen = len;
 367
 368                rx_desc->addr0 = dst;
 369                rx_desc->flags = HSDMA_DESC_PLEN0(tlen);
 370
 371                dst += tlen;
 372                len -= tlen;
 373
 374                /* update index */
 375                rx_idx = HSDMA_NEXT_DESC(rx_idx);
 376        }
 377
 378        /* make sure desc and index all up to date */
 379        wmb();
 380        mtk_hsdma_write(hsdma, HSDMA_REG_TX_CTX, chan->tx_idx);
 381
 382        return 0;
 383}
 384
 385static int gdma_next_desc(struct mtk_hsdma_chan *chan)
 386{
 387        struct virt_dma_desc *vdesc;
 388
 389        vdesc = vchan_next_desc(&chan->vchan);
 390        if (!vdesc) {
 391                chan->desc = NULL;
 392                return 0;
 393        }
 394        chan->desc = to_mtk_hsdma_desc(vdesc);
 395        chan->next_sg = 0;
 396
 397        return 1;
 398}
 399
 400static void mtk_hsdma_chan_done(struct mtk_hsdam_engine *hsdma,
 401                                struct mtk_hsdma_chan *chan)
 402{
 403        struct mtk_hsdma_desc *desc;
 404        int chan_issued;
 405
 406        chan_issued = 0;
 407        spin_lock_bh(&chan->vchan.lock);
 408        desc = chan->desc;
 409        if (likely(desc)) {
 410                if (chan->next_sg == desc->num_sgs) {
 411                        list_del(&desc->vdesc.node);
 412                        vchan_cookie_complete(&desc->vdesc);
 413                        chan_issued = gdma_next_desc(chan);
 414                }
 415        } else {
 416                dev_dbg(hsdma->ddev.dev, "no desc to complete\n");
 417        }
 418
 419        if (chan_issued)
 420                set_bit(chan->id, &hsdma->chan_issued);
 421        spin_unlock_bh(&chan->vchan.lock);
 422}
 423
 424static irqreturn_t mtk_hsdma_irq(int irq, void *devid)
 425{
 426        struct mtk_hsdam_engine *hsdma = devid;
 427        u32 status;
 428
 429        status = mtk_hsdma_read(hsdma, HSDMA_REG_INT_STATUS);
 430        if (unlikely(!status))
 431                return IRQ_NONE;
 432
 433        if (likely(status & HSDMA_INT_RX_Q0))
 434                tasklet_schedule(&hsdma->task);
 435        else
 436                dev_dbg(hsdma->ddev.dev, "unhandle irq status %08x\n", status);
 437        /* clean intr bits */
 438        mtk_hsdma_write(hsdma, HSDMA_REG_INT_STATUS, status);
 439
 440        return IRQ_HANDLED;
 441}
 442
 443static void mtk_hsdma_issue_pending(struct dma_chan *c)
 444{
 445        struct mtk_hsdma_chan *chan = to_mtk_hsdma_chan(c);
 446        struct mtk_hsdam_engine *hsdma = mtk_hsdma_chan_get_dev(chan);
 447
 448        spin_lock_bh(&chan->vchan.lock);
 449        if (vchan_issue_pending(&chan->vchan) && !chan->desc) {
 450                if (gdma_next_desc(chan)) {
 451                        set_bit(chan->id, &hsdma->chan_issued);
 452                        tasklet_schedule(&hsdma->task);
 453                } else {
 454                        dev_dbg(hsdma->ddev.dev, "no desc to issue\n");
 455                }
 456        }
 457        spin_unlock_bh(&chan->vchan.lock);
 458}
 459
 460static struct dma_async_tx_descriptor *mtk_hsdma_prep_dma_memcpy(
 461                struct dma_chan *c, dma_addr_t dest, dma_addr_t src,
 462                size_t len, unsigned long flags)
 463{
 464        struct mtk_hsdma_chan *chan = to_mtk_hsdma_chan(c);
 465        struct mtk_hsdma_desc *desc;
 466
 467        if (len <= 0)
 468                return NULL;
 469
 470        desc = kzalloc(sizeof(*desc), GFP_ATOMIC);
 471        if (!desc) {
 472                dev_err(c->device->dev, "alloc memcpy decs error\n");
 473                return NULL;
 474        }
 475
 476        desc->sg[0].src_addr = src;
 477        desc->sg[0].dst_addr = dest;
 478        desc->sg[0].len = len;
 479
 480        return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
 481}
 482
 483static enum dma_status mtk_hsdma_tx_status(struct dma_chan *c,
 484                                           dma_cookie_t cookie,
 485                                           struct dma_tx_state *state)
 486{
 487        return dma_cookie_status(c, cookie, state);
 488}
 489
 490static void mtk_hsdma_free_chan_resources(struct dma_chan *c)
 491{
 492        vchan_free_chan_resources(to_virt_chan(c));
 493}
 494
 495static void mtk_hsdma_desc_free(struct virt_dma_desc *vdesc)
 496{
 497        kfree(container_of(vdesc, struct mtk_hsdma_desc, vdesc));
 498}
 499
 500static void mtk_hsdma_tx(struct mtk_hsdam_engine *hsdma)
 501{
 502        struct mtk_hsdma_chan *chan;
 503
 504        if (test_and_clear_bit(0, &hsdma->chan_issued)) {
 505                chan = &hsdma->chan[0];
 506                if (chan->desc)
 507                        mtk_hsdma_start_transfer(hsdma, chan);
 508                else
 509                        dev_dbg(hsdma->ddev.dev, "chan 0 no desc to issue\n");
 510        }
 511}
 512
 513static void mtk_hsdma_rx(struct mtk_hsdam_engine *hsdma)
 514{
 515        struct mtk_hsdma_chan *chan;
 516        int next_idx, drx_idx, cnt;
 517
 518        chan = &hsdma->chan[0];
 519        next_idx = HSDMA_NEXT_DESC(chan->rx_idx);
 520        drx_idx = mtk_hsdma_read(hsdma, HSDMA_REG_RX_DRX);
 521
 522        cnt = (drx_idx - next_idx) & HSDMA_DESCS_MASK;
 523        if (!cnt)
 524                return;
 525
 526        chan->next_sg += cnt;
 527        chan->rx_idx = (chan->rx_idx + cnt) & HSDMA_DESCS_MASK;
 528
 529        /* update rx crx */
 530        wmb();
 531        mtk_hsdma_write(hsdma, HSDMA_REG_RX_CRX, chan->rx_idx);
 532
 533        mtk_hsdma_chan_done(hsdma, chan);
 534}
 535
 536static void mtk_hsdma_tasklet(struct tasklet_struct *t)
 537{
 538        struct mtk_hsdam_engine *hsdma = from_tasklet(hsdma, t, task);
 539
 540        mtk_hsdma_rx(hsdma);
 541        mtk_hsdma_tx(hsdma);
 542}
 543
 544static int mtk_hsdam_alloc_desc(struct mtk_hsdam_engine *hsdma,
 545                                struct mtk_hsdma_chan *chan)
 546{
 547        int i;
 548
 549        chan->tx_ring = dma_alloc_coherent(hsdma->ddev.dev,
 550                                           2 * HSDMA_DESCS_NUM *
 551                                           sizeof(*chan->tx_ring),
 552                        &chan->desc_addr, GFP_ATOMIC | __GFP_ZERO);
 553        if (!chan->tx_ring)
 554                goto no_mem;
 555
 556        chan->rx_ring = &chan->tx_ring[HSDMA_DESCS_NUM];
 557
 558        /* init tx ring value */
 559        for (i = 0; i < HSDMA_DESCS_NUM; i++)
 560                chan->tx_ring[i].flags = HSDMA_DESC_LS0 | HSDMA_DESC_DONE;
 561
 562        return 0;
 563no_mem:
 564        return -ENOMEM;
 565}
 566
 567static void mtk_hsdam_free_desc(struct mtk_hsdam_engine *hsdma,
 568                                struct mtk_hsdma_chan *chan)
 569{
 570        if (chan->tx_ring) {
 571                dma_free_coherent(hsdma->ddev.dev,
 572                                  2 * HSDMA_DESCS_NUM * sizeof(*chan->tx_ring),
 573                                  chan->tx_ring, chan->desc_addr);
 574                chan->tx_ring = NULL;
 575                chan->rx_ring = NULL;
 576        }
 577}
 578
 579static int mtk_hsdma_init(struct mtk_hsdam_engine *hsdma)
 580{
 581        struct mtk_hsdma_chan *chan;
 582        int ret;
 583        u32 reg;
 584
 585        /* init desc */
 586        chan = &hsdma->chan[0];
 587        ret = mtk_hsdam_alloc_desc(hsdma, chan);
 588        if (ret)
 589                return ret;
 590
 591        /* tx */
 592        mtk_hsdma_write(hsdma, HSDMA_REG_TX_BASE, chan->desc_addr);
 593        mtk_hsdma_write(hsdma, HSDMA_REG_TX_CNT, HSDMA_DESCS_NUM);
 594        /* rx */
 595        mtk_hsdma_write(hsdma, HSDMA_REG_RX_BASE, chan->desc_addr +
 596                        (sizeof(struct hsdma_desc) * HSDMA_DESCS_NUM));
 597        mtk_hsdma_write(hsdma, HSDMA_REG_RX_CNT, HSDMA_DESCS_NUM);
 598        /* reset */
 599        mtk_hsdma_reset_chan(hsdma, chan);
 600
 601        /* enable rx intr */
 602        mtk_hsdma_write(hsdma, HSDMA_REG_INT_MASK, HSDMA_INT_RX_Q0);
 603
 604        /* enable dma */
 605        mtk_hsdma_write(hsdma, HSDMA_REG_GLO_CFG, HSDMA_GLO_DEFAULT);
 606
 607        /* hardware info */
 608        reg = mtk_hsdma_read(hsdma, HSDMA_REG_INFO);
 609        dev_info(hsdma->ddev.dev, "rx: %d, tx: %d\n",
 610                 (reg >> HSDMA_INFO_RX_SHIFT) & HSDMA_INFO_RX_MASK,
 611                 (reg >> HSDMA_INFO_TX_SHIFT) & HSDMA_INFO_TX_MASK);
 612
 613        hsdma_dump_reg(hsdma);
 614
 615        return ret;
 616}
 617
 618static void mtk_hsdma_uninit(struct mtk_hsdam_engine *hsdma)
 619{
 620        struct mtk_hsdma_chan *chan;
 621
 622        /* disable dma */
 623        mtk_hsdma_write(hsdma, HSDMA_REG_GLO_CFG, 0);
 624
 625        /* disable intr */
 626        mtk_hsdma_write(hsdma, HSDMA_REG_INT_MASK, 0);
 627
 628        /* free desc */
 629        chan = &hsdma->chan[0];
 630        mtk_hsdam_free_desc(hsdma, chan);
 631
 632        /* tx */
 633        mtk_hsdma_write(hsdma, HSDMA_REG_TX_BASE, 0);
 634        mtk_hsdma_write(hsdma, HSDMA_REG_TX_CNT, 0);
 635        /* rx */
 636        mtk_hsdma_write(hsdma, HSDMA_REG_RX_BASE, 0);
 637        mtk_hsdma_write(hsdma, HSDMA_REG_RX_CNT, 0);
 638        /* reset */
 639        mtk_hsdma_reset_chan(hsdma, chan);
 640}
 641
 642static const struct of_device_id mtk_hsdma_of_match[] = {
 643        { .compatible = "mediatek,mt7621-hsdma" },
 644        { },
 645};
 646
 647static int mtk_hsdma_probe(struct platform_device *pdev)
 648{
 649        const struct of_device_id *match;
 650        struct mtk_hsdma_chan *chan;
 651        struct mtk_hsdam_engine *hsdma;
 652        struct dma_device *dd;
 653        int ret;
 654        int irq;
 655        void __iomem *base;
 656
 657        ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 658        if (ret)
 659                return ret;
 660
 661        match = of_match_device(mtk_hsdma_of_match, &pdev->dev);
 662        if (!match)
 663                return -EINVAL;
 664
 665        hsdma = devm_kzalloc(&pdev->dev, sizeof(*hsdma), GFP_KERNEL);
 666        if (!hsdma)
 667                return -EINVAL;
 668
 669        base = devm_platform_ioremap_resource(pdev, 0);
 670        if (IS_ERR(base))
 671                return PTR_ERR(base);
 672        hsdma->base = base + HSDMA_BASE_OFFSET;
 673        tasklet_setup(&hsdma->task, mtk_hsdma_tasklet);
 674
 675        irq = platform_get_irq(pdev, 0);
 676        if (irq < 0)
 677                return -EINVAL;
 678        ret = devm_request_irq(&pdev->dev, irq, mtk_hsdma_irq,
 679                               0, dev_name(&pdev->dev), hsdma);
 680        if (ret) {
 681                dev_err(&pdev->dev, "failed to request irq\n");
 682                return ret;
 683        }
 684
 685        device_reset(&pdev->dev);
 686
 687        dd = &hsdma->ddev;
 688        dma_cap_set(DMA_MEMCPY, dd->cap_mask);
 689        dd->copy_align = HSDMA_ALIGN_SIZE;
 690        dd->device_free_chan_resources = mtk_hsdma_free_chan_resources;
 691        dd->device_prep_dma_memcpy = mtk_hsdma_prep_dma_memcpy;
 692        dd->device_terminate_all = mtk_hsdma_terminate_all;
 693        dd->device_tx_status = mtk_hsdma_tx_status;
 694        dd->device_issue_pending = mtk_hsdma_issue_pending;
 695        dd->dev = &pdev->dev;
 696        dd->dev->dma_parms = &hsdma->dma_parms;
 697        dma_set_max_seg_size(dd->dev, HSDMA_MAX_PLEN);
 698        INIT_LIST_HEAD(&dd->channels);
 699
 700        chan = &hsdma->chan[0];
 701        chan->id = 0;
 702        chan->vchan.desc_free = mtk_hsdma_desc_free;
 703        vchan_init(&chan->vchan, dd);
 704
 705        /* init hardware */
 706        ret = mtk_hsdma_init(hsdma);
 707        if (ret) {
 708                dev_err(&pdev->dev, "failed to alloc ring descs\n");
 709                return ret;
 710        }
 711
 712        ret = dma_async_device_register(dd);
 713        if (ret) {
 714                dev_err(&pdev->dev, "failed to register dma device\n");
 715                goto err_uninit_hsdma;
 716        }
 717
 718        ret = of_dma_controller_register(pdev->dev.of_node,
 719                                         of_dma_xlate_by_chan_id, hsdma);
 720        if (ret) {
 721                dev_err(&pdev->dev, "failed to register of dma controller\n");
 722                goto err_unregister;
 723        }
 724
 725        platform_set_drvdata(pdev, hsdma);
 726
 727        return 0;
 728
 729err_unregister:
 730        dma_async_device_unregister(dd);
 731err_uninit_hsdma:
 732        mtk_hsdma_uninit(hsdma);
 733        return ret;
 734}
 735
 736static int mtk_hsdma_remove(struct platform_device *pdev)
 737{
 738        struct mtk_hsdam_engine *hsdma = platform_get_drvdata(pdev);
 739
 740        mtk_hsdma_uninit(hsdma);
 741
 742        of_dma_controller_free(pdev->dev.of_node);
 743        dma_async_device_unregister(&hsdma->ddev);
 744
 745        return 0;
 746}
 747
 748static struct platform_driver mtk_hsdma_driver = {
 749        .probe = mtk_hsdma_probe,
 750        .remove = mtk_hsdma_remove,
 751        .driver = {
 752                .name = KBUILD_MODNAME,
 753                .of_match_table = mtk_hsdma_of_match,
 754        },
 755};
 756module_platform_driver(mtk_hsdma_driver);
 757
 758MODULE_AUTHOR("Michael Lee <igvtee@gmail.com>");
 759MODULE_DESCRIPTION("MTK HSDMA driver");
 760MODULE_LICENSE("GPL v2");
 761