drivers/dma/qcom/bam_dma.c

   1 /*
   2  * Copyright (c) 2013-2014, The Linux Foundation. All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 and
   6  * only version 2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  */
  14 /*
  15  * QCOM BAM DMA engine driver
  16  *
  17  * QCOM BAM DMA blocks are distributed amongst a number of the on-chip
  18  * peripherals on the MSM 8x74.  The configuration of the channels are dependent
  19  * on the way they are hard wired to that specific peripheral.  The peripheral
  20  * device tree entries specify the configuration of each channel.
  21  *
  22  * The DMA controller requires the use of external memory for storage of the
  23  * hardware descriptors for each channel.  The descriptor FIFO is accessed as a
  24  * circular buffer and operations are managed according to the offset within the
  25  * FIFO.  After pipe/channel reset, all of the pipe registers and internal state
  26  * are back to defaults.
  27  *
  28  * During DMA operations, we write descriptors to the FIFO, being careful to
  29  * handle wrapping and then write the last FIFO offset to that channel's
  30  * P_EVNT_REG register to kick off the transaction.  The P_SW_OFSTS register
  31  * indicates the current FIFO offset that is being processed, so there is some
  32  * indication of where the hardware is currently working.
  33  */
  34
  35 #include <linux/kernel.h>
  36 #include <linux/io.h>
  37 #include <linux/init.h>
  38 #include <linux/slab.h>
  39 #include <linux/module.h>
  40 #include <linux/interrupt.h>
  41 #include <linux/dma-mapping.h>
  42 #include <linux/scatterlist.h>
  43 #include <linux/device.h>
  44 #include <linux/platform_device.h>
  45 #include <linux/of.h>
  46 #include <linux/of_address.h>
  47 #include <linux/of_irq.h>
  48 #include <linux/of_dma.h>
  49 #include <linux/clk.h>
  50 #include <linux/dmaengine.h>
  51 #include <linux/pm_runtime.h>
  52
  53 #include "../dmaengine.h"
  54 #include "../virt-dma.h"
  55
  56 struct bam_desc_hw {
  57         __le32 addr;            /* Buffer physical address */
  58         __le16 size;            /* Buffer size in bytes */
  59         __le16 flags;
  60 };
  61
  62 #define BAM_DMA_AUTOSUSPEND_DELAY 100
  63
  64 #define DESC_FLAG_INT BIT(15)
  65 #define DESC_FLAG_EOT BIT(14)
  66 #define DESC_FLAG_EOB BIT(13)
  67 #define DESC_FLAG_NWD BIT(12)
  68
  69 struct bam_async_desc {
  70         struct virt_dma_desc vd;
  71
  72         u32 num_desc;
  73         u32 xfer_len;
  74
  75         /* transaction flags, EOT|EOB|NWD */
  76         u16 flags;
  77
  78         struct bam_desc_hw *curr_desc;
  79
  80         enum dma_transfer_direction dir;
  81         size_t length;
  82         struct bam_desc_hw desc[0];
  83 };
  84
  85 enum bam_reg {
  86         BAM_CTRL,
  87         BAM_REVISION,
  88         BAM_NUM_PIPES,
  89         BAM_DESC_CNT_TRSHLD,
  90         BAM_IRQ_SRCS,
  91         BAM_IRQ_SRCS_MSK,
  92         BAM_IRQ_SRCS_UNMASKED,
  93         BAM_IRQ_STTS,
  94         BAM_IRQ_CLR,
  95         BAM_IRQ_EN,
  96         BAM_CNFG_BITS,
  97         BAM_IRQ_SRCS_EE,
  98         BAM_IRQ_SRCS_MSK_EE,
  99         BAM_P_CTRL,
 100         BAM_P_RST,
 101         BAM_P_HALT,
 102         BAM_P_IRQ_STTS,
 103         BAM_P_IRQ_CLR,
 104         BAM_P_IRQ_EN,
 105         BAM_P_EVNT_DEST_ADDR,
 106         BAM_P_EVNT_REG,
 107         BAM_P_SW_OFSTS,
 108         BAM_P_DATA_FIFO_ADDR,
 109         BAM_P_DESC_FIFO_ADDR,
 110         BAM_P_EVNT_GEN_TRSHLD,
 111         BAM_P_FIFO_SIZES,
 112 };
 113
 114 struct reg_offset_data {
 115         u32 base_offset;
 116         unsigned int pipe_mult, evnt_mult, ee_mult;
 117 };
 118
 119 static const struct reg_offset_data bam_v1_3_reg_info[] = {
 120         [BAM_CTRL]              = { 0x0F80, 0x00, 0x00, 0x00 },
 121         [BAM_REVISION]          = { 0x0F84, 0x00, 0x00, 0x00 },
 122         [BAM_NUM_PIPES]         = { 0x0FBC, 0x00, 0x00, 0x00 },
 123         [BAM_DESC_CNT_TRSHLD]   = { 0x0F88, 0x00, 0x00, 0x00 },
 124         [BAM_IRQ_SRCS]          = { 0x0F8C, 0x00, 0x00, 0x00 },
 125         [BAM_IRQ_SRCS_MSK]      = { 0x0F90, 0x00, 0x00, 0x00 },
 126         [BAM_IRQ_SRCS_UNMASKED] = { 0x0FB0, 0x00, 0x00, 0x00 },
 127         [BAM_IRQ_STTS]          = { 0x0F94, 0x00, 0x00, 0x00 },
 128         [BAM_IRQ_CLR]           = { 0x0F98, 0x00, 0x00, 0x00 },
 129         [BAM_IRQ_EN]            = { 0x0F9C, 0x00, 0x00, 0x00 },
 130         [BAM_CNFG_BITS]         = { 0x0FFC, 0x00, 0x00, 0x00 },
 131         [BAM_IRQ_SRCS_EE]       = { 0x1800, 0x00, 0x00, 0x80 },
 132         [BAM_IRQ_SRCS_MSK_EE]   = { 0x1804, 0x00, 0x00, 0x80 },
 133         [BAM_P_CTRL]            = { 0x0000, 0x80, 0x00, 0x00 },
 134         [BAM_P_RST]             = { 0x0004, 0x80, 0x00, 0x00 },
 135         [BAM_P_HALT]            = { 0x0008, 0x80, 0x00, 0x00 },
 136         [BAM_P_IRQ_STTS]        = { 0x0010, 0x80, 0x00, 0x00 },
 137         [BAM_P_IRQ_CLR]         = { 0x0014, 0x80, 0x00, 0x00 },
 138         [BAM_P_IRQ_EN]          = { 0x0018, 0x80, 0x00, 0x00 },
 139         [BAM_P_EVNT_DEST_ADDR]  = { 0x102C, 0x00, 0x40, 0x00 },
 140         [BAM_P_EVNT_REG]        = { 0x1018, 0x00, 0x40, 0x00 },
 141         [BAM_P_SW_OFSTS]        = { 0x1000, 0x00, 0x40, 0x00 },
 142         [BAM_P_DATA_FIFO_ADDR]  = { 0x1024, 0x00, 0x40, 0x00 },
 143         [BAM_P_DESC_FIFO_ADDR]  = { 0x101C, 0x00, 0x40, 0x00 },
 144         [BAM_P_EVNT_GEN_TRSHLD] = { 0x1028, 0x00, 0x40, 0x00 },
 145         [BAM_P_FIFO_SIZES]      = { 0x1020, 0x00, 0x40, 0x00 },
 146 };
 147
 148 static const struct reg_offset_data bam_v1_4_reg_info[] = {
 149         [BAM_CTRL]              = { 0x0000, 0x00, 0x00, 0x00 },
 150         [BAM_REVISION]          = { 0x0004, 0x00, 0x00, 0x00 },
 151         [BAM_NUM_PIPES]         = { 0x003C, 0x00, 0x00, 0x00 },
 152         [BAM_DESC_CNT_TRSHLD]   = { 0x0008, 0x00, 0x00, 0x00 },
 153         [BAM_IRQ_SRCS]          = { 0x000C, 0x00, 0x00, 0x00 },
 154         [BAM_IRQ_SRCS_MSK]      = { 0x0010, 0x00, 0x00, 0x00 },
 155         [BAM_IRQ_SRCS_UNMASKED] = { 0x0030, 0x00, 0x00, 0x00 },
 156         [BAM_IRQ_STTS]          = { 0x0014, 0x00, 0x00, 0x00 },
 157         [BAM_IRQ_CLR]           = { 0x0018, 0x00, 0x00, 0x00 },
 158         [BAM_IRQ_EN]            = { 0x001C, 0x00, 0x00, 0x00 },
 159         [BAM_CNFG_BITS]         = { 0x007C, 0x00, 0x00, 0x00 },
 160         [BAM_IRQ_SRCS_EE]       = { 0x0800, 0x00, 0x00, 0x80 },
 161         [BAM_IRQ_SRCS_MSK_EE]   = { 0x0804, 0x00, 0x00, 0x80 },
 162         [BAM_P_CTRL]            = { 0x1000, 0x1000, 0x00, 0x00 },
 163         [BAM_P_RST]             = { 0x1004, 0x1000, 0x00, 0x00 },
 164         [BAM_P_HALT]            = { 0x1008, 0x1000, 0x00, 0x00 },
 165         [BAM_P_IRQ_STTS]        = { 0x1010, 0x1000, 0x00, 0x00 },
 166         [BAM_P_IRQ_CLR]         = { 0x1014, 0x1000, 0x00, 0x00 },
 167         [BAM_P_IRQ_EN]          = { 0x1018, 0x1000, 0x00, 0x00 },
 168         [BAM_P_EVNT_DEST_ADDR]  = { 0x182C, 0x00, 0x1000, 0x00 },
 169         [BAM_P_EVNT_REG]        = { 0x1818, 0x00, 0x1000, 0x00 },
 170         [BAM_P_SW_OFSTS]        = { 0x1800, 0x00, 0x1000, 0x00 },
 171         [BAM_P_DATA_FIFO_ADDR]  = { 0x1824, 0x00, 0x1000, 0x00 },
 172         [BAM_P_DESC_FIFO_ADDR]  = { 0x181C, 0x00, 0x1000, 0x00 },
 173         [BAM_P_EVNT_GEN_TRSHLD] = { 0x1828, 0x00, 0x1000, 0x00 },
 174         [BAM_P_FIFO_SIZES]      = { 0x1820, 0x00, 0x1000, 0x00 },
 175 };
 176
 177 static const struct reg_offset_data bam_v1_7_reg_info[] = {
 178         [BAM_CTRL]              = { 0x00000, 0x00, 0x00, 0x00 },
 179         [BAM_REVISION]          = { 0x01000, 0x00, 0x00, 0x00 },
 180         [BAM_NUM_PIPES]         = { 0x01008, 0x00, 0x00, 0x00 },
 181         [BAM_DESC_CNT_TRSHLD]   = { 0x00008, 0x00, 0x00, 0x00 },
 182         [BAM_IRQ_SRCS]          = { 0x03010, 0x00, 0x00, 0x00 },
 183         [BAM_IRQ_SRCS_MSK]      = { 0x03014, 0x00, 0x00, 0x00 },
 184         [BAM_IRQ_SRCS_UNMASKED] = { 0x03018, 0x00, 0x00, 0x00 },
 185         [BAM_IRQ_STTS]          = { 0x00014, 0x00, 0x00, 0x00 },
 186         [BAM_IRQ_CLR]           = { 0x00018, 0x00, 0x00, 0x00 },
 187         [BAM_IRQ_EN]            = { 0x0001C, 0x00, 0x00, 0x00 },
 188         [BAM_CNFG_BITS]         = { 0x0007C, 0x00, 0x00, 0x00 },
 189         [BAM_IRQ_SRCS_EE]       = { 0x03000, 0x00, 0x00, 0x1000 },
 190         [BAM_IRQ_SRCS_MSK_EE]   = { 0x03004, 0x00, 0x00, 0x1000 },
 191         [BAM_P_CTRL]            = { 0x13000, 0x1000, 0x00, 0x00 },
 192         [BAM_P_RST]             = { 0x13004, 0x1000, 0x00, 0x00 },
 193         [BAM_P_HALT]            = { 0x13008, 0x1000, 0x00, 0x00 },
 194         [BAM_P_IRQ_STTS]        = { 0x13010, 0x1000, 0x00, 0x00 },
 195         [BAM_P_IRQ_CLR]         = { 0x13014, 0x1000, 0x00, 0x00 },
 196         [BAM_P_IRQ_EN]          = { 0x13018, 0x1000, 0x00, 0x00 },
 197         [BAM_P_EVNT_DEST_ADDR]  = { 0x1382C, 0x00, 0x1000, 0x00 },
 198         [BAM_P_EVNT_REG]        = { 0x13818, 0x00, 0x1000, 0x00 },
 199         [BAM_P_SW_OFSTS]        = { 0x13800, 0x00, 0x1000, 0x00 },
 200         [BAM_P_DATA_FIFO_ADDR]  = { 0x13824, 0x00, 0x1000, 0x00 },
 201         [BAM_P_DESC_FIFO_ADDR]  = { 0x1381C, 0x00, 0x1000, 0x00 },
 202         [BAM_P_EVNT_GEN_TRSHLD] = { 0x13828, 0x00, 0x1000, 0x00 },
 203         [BAM_P_FIFO_SIZES]      = { 0x13820, 0x00, 0x1000, 0x00 },
 204 };
 205
 206 /* BAM CTRL */
 207 #define BAM_SW_RST                      BIT(0)
 208 #define BAM_EN                          BIT(1)
 209 #define BAM_EN_ACCUM                    BIT(4)
 210 #define BAM_TESTBUS_SEL_SHIFT           5
 211 #define BAM_TESTBUS_SEL_MASK            0x3F
 212 #define BAM_DESC_CACHE_SEL_SHIFT        13
 213 #define BAM_DESC_CACHE_SEL_MASK         0x3
 214 #define BAM_CACHED_DESC_STORE           BIT(15)
 215 #define IBC_DISABLE                     BIT(16)
 216
 217 /* BAM REVISION */
 218 #define REVISION_SHIFT          0
 219 #define REVISION_MASK           0xFF
 220 #define NUM_EES_SHIFT           8
 221 #define NUM_EES_MASK            0xF
 222 #define CE_BUFFER_SIZE          BIT(13)
 223 #define AXI_ACTIVE              BIT(14)
 224 #define USE_VMIDMT              BIT(15)
 225 #define SECURED                 BIT(16)
 226 #define BAM_HAS_NO_BYPASS       BIT(17)
 227 #define HIGH_FREQUENCY_BAM      BIT(18)
 228 #define INACTIV_TMRS_EXST       BIT(19)
 229 #define NUM_INACTIV_TMRS        BIT(20)
 230 #define DESC_CACHE_DEPTH_SHIFT  21
 231 #define DESC_CACHE_DEPTH_1      (0 << DESC_CACHE_DEPTH_SHIFT)
 232 #define DESC_CACHE_DEPTH_2      (1 << DESC_CACHE_DEPTH_SHIFT)
 233 #define DESC_CACHE_DEPTH_3      (2 << DESC_CACHE_DEPTH_SHIFT)
 234 #define DESC_CACHE_DEPTH_4      (3 << DESC_CACHE_DEPTH_SHIFT)
 235 #define CMD_DESC_EN             BIT(23)
 236 #define INACTIV_TMR_BASE_SHIFT  24
 237 #define INACTIV_TMR_BASE_MASK   0xFF
 238
 239 /* BAM NUM PIPES */
 240 #define BAM_NUM_PIPES_SHIFT             0
 241 #define BAM_NUM_PIPES_MASK              0xFF
 242 #define PERIPH_NON_PIPE_GRP_SHIFT       16
 243 #define PERIPH_NON_PIP_GRP_MASK         0xFF
 244 #define BAM_NON_PIPE_GRP_SHIFT          24
 245 #define BAM_NON_PIPE_GRP_MASK           0xFF
 246
 247 /* BAM CNFG BITS */
 248 #define BAM_PIPE_CNFG           BIT(2)
 249 #define BAM_FULL_PIPE           BIT(11)
 250 #define BAM_NO_EXT_P_RST        BIT(12)
 251 #define BAM_IBC_DISABLE         BIT(13)
 252 #define BAM_SB_CLK_REQ          BIT(14)
 253 #define BAM_PSM_CSW_REQ         BIT(15)
 254 #define BAM_PSM_P_RES           BIT(16)
 255 #define BAM_AU_P_RES            BIT(17)
 256 #define BAM_SI_P_RES            BIT(18)
 257 #define BAM_WB_P_RES            BIT(19)
 258 #define BAM_WB_BLK_CSW          BIT(20)
 259 #define BAM_WB_CSW_ACK_IDL      BIT(21)
 260 #define BAM_WB_RETR_SVPNT       BIT(22)
 261 #define BAM_WB_DSC_AVL_P_RST    BIT(23)
 262 #define BAM_REG_P_EN            BIT(24)
 263 #define BAM_PSM_P_HD_DATA       BIT(25)
 264 #define BAM_AU_ACCUMED          BIT(26)
 265 #define BAM_CMD_ENABLE          BIT(27)
 266
 267 #define BAM_CNFG_BITS_DEFAULT   (BAM_PIPE_CNFG |        \
 268                                  BAM_NO_EXT_P_RST |     \
 269                                  BAM_IBC_DISABLE |      \
 270                                  BAM_SB_CLK_REQ |       \
 271                                  BAM_PSM_CSW_REQ |      \
 272                                  BAM_PSM_P_RES |        \
 273                                  BAM_AU_P_RES |         \
 274                                  BAM_SI_P_RES |         \
 275                                  BAM_WB_P_RES |         \
 276                                  BAM_WB_BLK_CSW |       \
 277                                  BAM_WB_CSW_ACK_IDL |   \
 278                                  BAM_WB_RETR_SVPNT |    \
 279                                  BAM_WB_DSC_AVL_P_RST | \
 280                                  BAM_REG_P_EN |         \
 281                                  BAM_PSM_P_HD_DATA |    \
 282                                  BAM_AU_ACCUMED |       \
 283                                  BAM_CMD_ENABLE)
 284
 285 /* PIPE CTRL */
 286 #define P_EN                    BIT(1)
 287 #define P_DIRECTION             BIT(3)
 288 #define P_SYS_STRM              BIT(4)
 289 #define P_SYS_MODE              BIT(5)
 290 #define P_AUTO_EOB              BIT(6)
 291 #define P_AUTO_EOB_SEL_SHIFT    7
 292 #define P_AUTO_EOB_SEL_512      (0 << P_AUTO_EOB_SEL_SHIFT)
 293 #define P_AUTO_EOB_SEL_256      (1 << P_AUTO_EOB_SEL_SHIFT)
 294 #define P_AUTO_EOB_SEL_128      (2 << P_AUTO_EOB_SEL_SHIFT)
 295 #define P_AUTO_EOB_SEL_64       (3 << P_AUTO_EOB_SEL_SHIFT)
 296 #define P_PREFETCH_LIMIT_SHIFT  9
 297 #define P_PREFETCH_LIMIT_32     (0 << P_PREFETCH_LIMIT_SHIFT)
 298 #define P_PREFETCH_LIMIT_16     (1 << P_PREFETCH_LIMIT_SHIFT)
 299 #define P_PREFETCH_LIMIT_4      (2 << P_PREFETCH_LIMIT_SHIFT)
 300 #define P_WRITE_NWD             BIT(11)
 301 #define P_LOCK_GROUP_SHIFT      16
 302 #define P_LOCK_GROUP_MASK       0x1F
 303
 304 /* BAM_DESC_CNT_TRSHLD */
 305 #define CNT_TRSHLD              0xffff
 306 #define DEFAULT_CNT_THRSHLD     0x4
 307
 308 /* BAM_IRQ_SRCS */
 309 #define BAM_IRQ                 BIT(31)
 310 #define P_IRQ                   0x7fffffff
 311
 312 /* BAM_IRQ_SRCS_MSK */
 313 #define BAM_IRQ_MSK             BAM_IRQ
 314 #define P_IRQ_MSK               P_IRQ
 315
 316 /* BAM_IRQ_STTS */
 317 #define BAM_TIMER_IRQ           BIT(4)
 318 #define BAM_EMPTY_IRQ           BIT(3)
 319 #define BAM_ERROR_IRQ           BIT(2)
 320 #define BAM_HRESP_ERR_IRQ       BIT(1)
 321
 322 /* BAM_IRQ_CLR */
 323 #define BAM_TIMER_CLR           BIT(4)
 324 #define BAM_EMPTY_CLR           BIT(3)
 325 #define BAM_ERROR_CLR           BIT(2)
 326 #define BAM_HRESP_ERR_CLR       BIT(1)
 327
 328 /* BAM_IRQ_EN */
 329 #define BAM_TIMER_EN            BIT(4)
 330 #define BAM_EMPTY_EN            BIT(3)
 331 #define BAM_ERROR_EN            BIT(2)
 332 #define BAM_HRESP_ERR_EN        BIT(1)
 333
 334 /* BAM_P_IRQ_EN */
 335 #define P_PRCSD_DESC_EN         BIT(0)
 336 #define P_TIMER_EN              BIT(1)
 337 #define P_WAKE_EN               BIT(2)
 338 #define P_OUT_OF_DESC_EN        BIT(3)
 339 #define P_ERR_EN                BIT(4)
 340 #define P_TRNSFR_END_EN         BIT(5)
 341 #define P_DEFAULT_IRQS_EN       (P_PRCSD_DESC_EN | P_ERR_EN | P_TRNSFR_END_EN)
 342
 343 /* BAM_P_SW_OFSTS */
 344 #define P_SW_OFSTS_MASK         0xffff
 345
 346 #define BAM_DESC_FIFO_SIZE      SZ_32K
 347 #define MAX_DESCRIPTORS (BAM_DESC_FIFO_SIZE / sizeof(struct bam_desc_hw) - 1)
 348 #define BAM_FIFO_SIZE   (SZ_32K - 8)
 349
 350 struct bam_chan {
 351         struct virt_dma_chan vc;
 352
 353         struct bam_device *bdev;
 354
 355         /* configuration from device tree */
 356         u32 id;
 357
 358         struct bam_async_desc *curr_txd;        /* current running dma */
 359
 360         /* runtime configuration */
 361         struct dma_slave_config slave;
 362
 363         /* fifo storage */
 364         struct bam_desc_hw *fifo_virt;
 365         dma_addr_t fifo_phys;
 366
 367         /* fifo markers */
 368         unsigned short head;            /* start of active descriptor entries */
 369         unsigned short tail;            /* end of active descriptor entries */
 370
 371         unsigned int initialized;       /* is the channel hw initialized? */
 372         unsigned int paused;            /* is the channel paused? */
 373         unsigned int reconfigure;       /* new slave config? */
 374
 375         struct list_head node;
 376 };
 377
 378 static inline struct bam_chan *to_bam_chan(struct dma_chan *common)
 379 {
 380         return container_of(common, struct bam_chan, vc.chan);
 381 }
 382
 383 struct bam_device {
 384         void __iomem *regs;
 385         struct device *dev;
 386         struct dma_device common;
 387         struct device_dma_parameters dma_parms;
 388         struct bam_chan *channels;
 389         u32 num_channels;
 390         u32 num_ees;
 391
 392         /* execution environment ID, from DT */
 393         u32 ee;
 394         bool controlled_remotely;
 395
 396         const struct reg_offset_data *layout;
 397
 398         struct clk *bamclk;
 399         int irq;
 400
 401         /* dma start transaction tasklet */
 402         struct tasklet_struct task;
 403 };
 404
 405 /**
 406  * bam_addr - returns BAM register address
 407  * @bdev: bam device
 408  * @pipe: pipe instance (ignored when register doesn't have multiple instances)
 409  * @reg:  register enum
 410  */
 411 static inline void __iomem *bam_addr(struct bam_device *bdev, u32 pipe,
 412                 enum bam_reg reg)
 413 {
 414         const struct reg_offset_data r = bdev->layout[reg];
 415
 416         return bdev->regs + r.base_offset +
 417                 r.pipe_mult * pipe +
 418                 r.evnt_mult * pipe +
 419                 r.ee_mult * bdev->ee;
 420 }
 421
 422 /**
 423  * bam_reset_channel - Reset individual BAM DMA channel
 424  * @bchan: bam channel
 425  *
 426  * This function resets a specific BAM channel
 427  */
 428 static void bam_reset_channel(struct bam_chan *bchan)
 429 {
 430         struct bam_device *bdev = bchan->bdev;
 431
 432         lockdep_assert_held(&bchan->vc.lock);
 433
 434         /* reset channel */
 435         writel_relaxed(1, bam_addr(bdev, bchan->id, BAM_P_RST));
 436         writel_relaxed(0, bam_addr(bdev, bchan->id, BAM_P_RST));
 437
 438         /* don't allow cpu to reorder BAM register accesses done after this */
 439         wmb();
 440
 441         /* make sure hw is initialized when channel is used the first time  */
 442         bchan->initialized = 0;
 443 }
 444
 445 /**
 446  * bam_chan_init_hw - Initialize channel hardware
 447  * @bchan: bam channel
 448  *
 449  * This function resets and initializes the BAM channel
 450  */
 451 static void bam_chan_init_hw(struct bam_chan *bchan,
 452         enum dma_transfer_direction dir)
 453 {
 454         struct bam_device *bdev = bchan->bdev;
 455         u32 val;
 456
 457         /* Reset the channel to clear internal state of the FIFO */
 458         bam_reset_channel(bchan);
 459
 460         /*
 461          * write out 8 byte aligned address.  We have enough space for this
 462          * because we allocated 1 more descriptor (8 bytes) than we can use
 463          */
 464         writel_relaxed(ALIGN(bchan->fifo_phys, sizeof(struct bam_desc_hw)),
 465                         bam_addr(bdev, bchan->id, BAM_P_DESC_FIFO_ADDR));
 466         writel_relaxed(BAM_FIFO_SIZE,
 467                         bam_addr(bdev, bchan->id, BAM_P_FIFO_SIZES));
 468
 469         /* enable the per pipe interrupts, enable EOT, ERR, and INT irqs */
 470         writel_relaxed(P_DEFAULT_IRQS_EN,
 471                         bam_addr(bdev, bchan->id, BAM_P_IRQ_EN));
 472
 473         /* unmask the specific pipe and EE combo */
 474         val = readl_relaxed(bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE));
 475         val |= BIT(bchan->id);
 476         writel_relaxed(val, bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE));
 477
 478         /* don't allow cpu to reorder the channel enable done below */
 479         wmb();
 480
 481         /* set fixed direction and mode, then enable channel */
 482         val = P_EN | P_SYS_MODE;
 483         if (dir == DMA_DEV_TO_MEM)
 484                 val |= P_DIRECTION;
 485
 486         writel_relaxed(val, bam_addr(bdev, bchan->id, BAM_P_CTRL));
 487
 488         bchan->initialized = 1;
 489
 490         /* init FIFO pointers */
 491         bchan->head = 0;
 492         bchan->tail = 0;
 493 }
 494
 495 /**
 496  * bam_alloc_chan - Allocate channel resources for DMA channel.
 497  * @chan: specified channel
 498  *
 499  * This function allocates the FIFO descriptor memory
 500  */
 501 static int bam_alloc_chan(struct dma_chan *chan)
 502 {
 503         struct bam_chan *bchan = to_bam_chan(chan);
 504         struct bam_device *bdev = bchan->bdev;
 505
 506         if (bchan->fifo_virt)
 507                 return 0;
 508
 509         /* allocate FIFO descriptor space, but only if necessary */
 510         bchan->fifo_virt = dma_alloc_wc(bdev->dev, BAM_DESC_FIFO_SIZE,
 511                                         &bchan->fifo_phys, GFP_KERNEL);
 512
 513         if (!bchan->fifo_virt) {
 514                 dev_err(bdev->dev, "Failed to allocate desc fifo\n");
 515                 return -ENOMEM;
 516         }
 517
 518         return 0;
 519 }
 520
 521 /**
 522  * bam_free_chan - Frees dma resources associated with specific channel
 523  * @chan: specified channel
 524  *
 525  * Free the allocated fifo descriptor memory and channel resources
 526  *
 527  */
 528 static void bam_free_chan(struct dma_chan *chan)
 529 {
 530         struct bam_chan *bchan = to_bam_chan(chan);
 531         struct bam_device *bdev = bchan->bdev;
 532         u32 val;
 533         unsigned long flags;
 534         int ret;
 535
 536         ret = pm_runtime_get_sync(bdev->dev);
 537         if (ret < 0)
 538                 return;
 539
 540         vchan_free_chan_resources(to_virt_chan(chan));
 541
 542         if (bchan->curr_txd) {
 543                 dev_err(bchan->bdev->dev, "Cannot free busy channel\n");
 544                 goto err;
 545         }
 546
 547         spin_lock_irqsave(&bchan->vc.lock, flags);
 548         bam_reset_channel(bchan);
 549         spin_unlock_irqrestore(&bchan->vc.lock, flags);
 550
 551         dma_free_wc(bdev->dev, BAM_DESC_FIFO_SIZE, bchan->fifo_virt,
 552                     bchan->fifo_phys);
 553         bchan->fifo_virt = NULL;
 554
 555         /* mask irq for pipe/channel */
 556         val = readl_relaxed(bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE));
 557         val &= ~BIT(bchan->id);
 558         writel_relaxed(val, bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE));
 559
 560         /* disable irq */
 561         writel_relaxed(0, bam_addr(bdev, bchan->id, BAM_P_IRQ_EN));
 562
 563 err:
 564         pm_runtime_mark_last_busy(bdev->dev);
 565         pm_runtime_put_autosuspend(bdev->dev);
 566 }
 567
 568 /**
 569  * bam_slave_config - set slave configuration for channel
 570  * @chan: dma channel
 571  * @cfg: slave configuration
 572  *
 573  * Sets slave configuration for channel
 574  *
 575  */
 576 static int bam_slave_config(struct dma_chan *chan,
 577                             struct dma_slave_config *cfg)
 578 {
 579         struct bam_chan *bchan = to_bam_chan(chan);
 580         unsigned long flag;
 581
 582         spin_lock_irqsave(&bchan->vc.lock, flag);
 583         memcpy(&bchan->slave, cfg, sizeof(*cfg));
 584         bchan->reconfigure = 1;
 585         spin_unlock_irqrestore(&bchan->vc.lock, flag);
 586
 587         return 0;
 588 }
 589
 590 /**
 591  * bam_prep_slave_sg - Prep slave sg transaction
 592  *
 593  * @chan: dma channel
 594  * @sgl: scatter gather list
 595  * @sg_len: length of sg
 596  * @direction: DMA transfer direction
 597  * @flags: DMA flags
 598  * @context: transfer context (unused)
 599  */
 600 static struct dma_async_tx_descriptor *bam_prep_slave_sg(struct dma_chan *chan,
 601         struct scatterlist *sgl, unsigned int sg_len,
 602         enum dma_transfer_direction direction, unsigned long flags,
 603         void *context)
 604 {
 605         struct bam_chan *bchan = to_bam_chan(chan);
 606         struct bam_device *bdev = bchan->bdev;
 607         struct bam_async_desc *async_desc;
 608         struct scatterlist *sg;
 609         u32 i;
 610         struct bam_desc_hw *desc;
 611         unsigned int num_alloc = 0;
 612
 613
 614         if (!is_slave_direction(direction)) {
 615                 dev_err(bdev->dev, "invalid dma direction\n");
 616                 return NULL;
 617         }
 618
 619         /* calculate number of required entries */
 620         for_each_sg(sgl, sg, sg_len, i)
 621                 num_alloc += DIV_ROUND_UP(sg_dma_len(sg), BAM_FIFO_SIZE);
 622
 623         /* allocate enough room to accomodate the number of entries */
 624         async_desc = kzalloc(sizeof(*async_desc) +
 625                         (num_alloc * sizeof(struct bam_desc_hw)), GFP_NOWAIT);
 626
 627         if (!async_desc)
 628                 goto err_out;
 629
 630         if (flags & DMA_PREP_FENCE)
 631                 async_desc->flags |= DESC_FLAG_NWD;
 632
 633         if (flags & DMA_PREP_INTERRUPT)
 634                 async_desc->flags |= DESC_FLAG_EOT;
 635         else
 636                 async_desc->flags |= DESC_FLAG_INT;
 637
 638         async_desc->num_desc = num_alloc;
 639         async_desc->curr_desc = async_desc->desc;
 640         async_desc->dir = direction;
 641
 642         /* fill in temporary descriptors */
 643         desc = async_desc->desc;
 644         for_each_sg(sgl, sg, sg_len, i) {
 645                 unsigned int remainder = sg_dma_len(sg);
 646                 unsigned int curr_offset = 0;
 647
 648                 do {
 649                         desc->addr = cpu_to_le32(sg_dma_address(sg) +
 650                                                  curr_offset);
 651
 652                         if (remainder > BAM_FIFO_SIZE) {
 653                                 desc->size = cpu_to_le16(BAM_FIFO_SIZE);
 654                                 remainder -= BAM_FIFO_SIZE;
 655                                 curr_offset += BAM_FIFO_SIZE;
 656                         } else {
 657                                 desc->size = cpu_to_le16(remainder);
 658                                 remainder = 0;
 659                         }
 660
 661                         async_desc->length += desc->size;
 662                         desc++;
 663                 } while (remainder > 0);
 664         }
 665
 666         return vchan_tx_prep(&bchan->vc, &async_desc->vd, flags);
 667
 668 err_out:
 669         kfree(async_desc);
 670         return NULL;
 671 }
 672
 673 /**
 674  * bam_dma_terminate_all - terminate all transactions on a channel
 675  * @bchan: bam dma channel
 676  *
 677  * Dequeues and frees all transactions
 678  * No callbacks are done
 679  *
 680  */
 681 static int bam_dma_terminate_all(struct dma_chan *chan)
 682 {
 683         struct bam_chan *bchan = to_bam_chan(chan);
 684         unsigned long flag;
 685         LIST_HEAD(head);
 686
 687         /* remove all transactions, including active transaction */
 688         spin_lock_irqsave(&bchan->vc.lock, flag);
 689         /*
 690          * If we have transactions queued, then some might be committed to the
 691          * hardware in the desc fifo.  The only way to reset the desc fifo is
 692          * to do a hardware reset (either by pipe or the entire block).
 693          * bam_chan_init_hw() will trigger a pipe reset, and also reinit the
 694          * pipe.  If the pipe is left disabled (default state after pipe reset)
 695          * and is accessed by a connected hardware engine, a fatal error in
 696          * the BAM will occur.  There is a small window where this could happen
 697          * with bam_chan_init_hw(), but it is assumed that the caller has
 698          * stopped activity on any attached hardware engine.  Make sure to do
 699          * this first so that the BAM hardware doesn't cause memory corruption
 700          * by accessing freed resources.
 701          */
 702         if (bchan->curr_txd) {
 703                 bam_chan_init_hw(bchan, bchan->curr_txd->dir);
 704                 list_add(&bchan->curr_txd->vd.node, &bchan->vc.desc_issued);
 705                 bchan->curr_txd = NULL;
 706         }
 707
 708         vchan_get_all_descriptors(&bchan->vc, &head);
 709         spin_unlock_irqrestore(&bchan->vc.lock, flag);
 710
 711         vchan_dma_desc_free_list(&bchan->vc, &head);
 712
 713         return 0;
 714 }
 715
 716 /**
 717  * bam_pause - Pause DMA channel
 718  * @chan: dma channel
 719  *
 720  */
 721 static int bam_pause(struct dma_chan *chan)
 722 {
 723         struct bam_chan *bchan = to_bam_chan(chan);
 724         struct bam_device *bdev = bchan->bdev;
 725         unsigned long flag;
 726         int ret;
 727
 728         ret = pm_runtime_get_sync(bdev->dev);
 729         if (ret < 0)
 730                 return ret;
 731
 732         spin_lock_irqsave(&bchan->vc.lock, flag);
 733         writel_relaxed(1, bam_addr(bdev, bchan->id, BAM_P_HALT));
 734         bchan->paused = 1;
 735         spin_unlock_irqrestore(&bchan->vc.lock, flag);
 736         pm_runtime_mark_last_busy(bdev->dev);
 737         pm_runtime_put_autosuspend(bdev->dev);
 738
 739         return 0;
 740 }
 741
 742 /**
 743  * bam_resume - Resume DMA channel operations
 744  * @chan: dma channel
 745  *
 746  */
 747 static int bam_resume(struct dma_chan *chan)
 748 {
 749         struct bam_chan *bchan = to_bam_chan(chan);
 750         struct bam_device *bdev = bchan->bdev;
 751         unsigned long flag;
 752         int ret;
 753
 754         ret = pm_runtime_get_sync(bdev->dev);
 755         if (ret < 0)
 756                 return ret;
 757
 758         spin_lock_irqsave(&bchan->vc.lock, flag);
 759         writel_relaxed(0, bam_addr(bdev, bchan->id, BAM_P_HALT));
 760         bchan->paused = 0;
 761         spin_unlock_irqrestore(&bchan->vc.lock, flag);
 762         pm_runtime_mark_last_busy(bdev->dev);
 763         pm_runtime_put_autosuspend(bdev->dev);
 764
 765         return 0;
 766 }
 767
 768 /**
 769  * process_channel_irqs - processes the channel interrupts
 770  * @bdev: bam controller
 771  *
 772  * This function processes the channel interrupts
 773  *
 774  */
 775 static u32 process_channel_irqs(struct bam_device *bdev)
 776 {
 777         u32 i, srcs, pipe_stts;
 778         unsigned long flags;
 779         struct bam_async_desc *async_desc;
 780
 781         srcs = readl_relaxed(bam_addr(bdev, 0, BAM_IRQ_SRCS_EE));
 782
 783         /* return early if no pipe/channel interrupts are present */
 784         if (!(srcs & P_IRQ))
 785                 return srcs;
 786
 787         for (i = 0; i < bdev->num_channels; i++) {
 788                 struct bam_chan *bchan = &bdev->channels[i];
 789
 790                 if (!(srcs & BIT(i)))
 791                         continue;
 792
 793                 /* clear pipe irq */
 794                 pipe_stts = readl_relaxed(bam_addr(bdev, i, BAM_P_IRQ_STTS));
 795
 796                 writel_relaxed(pipe_stts, bam_addr(bdev, i, BAM_P_IRQ_CLR));
 797
 798                 spin_lock_irqsave(&bchan->vc.lock, flags);
 799                 async_desc = bchan->curr_txd;
 800
 801                 if (async_desc) {
 802                         async_desc->num_desc -= async_desc->xfer_len;
 803                         async_desc->curr_desc += async_desc->xfer_len;
 804                         bchan->curr_txd = NULL;
 805
 806                         /* manage FIFO */
 807                         bchan->head += async_desc->xfer_len;
 808                         bchan->head %= MAX_DESCRIPTORS;
 809
 810                         /*
 811                          * if complete, process cookie.  Otherwise
 812                          * push back to front of desc_issued so that
 813                          * it gets restarted by the tasklet
 814                          */
 815                         if (!async_desc->num_desc)
 816                                 vchan_cookie_complete(&async_desc->vd);
 817                         else
 818                                 list_add(&async_desc->vd.node,
 819                                         &bchan->vc.desc_issued);
 820                 }
 821
 822                 spin_unlock_irqrestore(&bchan->vc.lock, flags);
 823         }
 824
 825         return srcs;
 826 }
 827
 828 /**
 829  * bam_dma_irq - irq handler for bam controller
 830  * @irq: IRQ of interrupt
 831  * @data: callback data
 832  *
 833  * IRQ handler for the bam controller
 834  */
 835 static irqreturn_t bam_dma_irq(int irq, void *data)
 836 {
 837         struct bam_device *bdev = data;
 838         u32 clr_mask = 0, srcs = 0;
 839         int ret;
 840
 841         srcs |= process_channel_irqs(bdev);
 842
 843         /* kick off tasklet to start next dma transfer */
 844         if (srcs & P_IRQ)
 845                 tasklet_schedule(&bdev->task);
 846
 847         ret = pm_runtime_get_sync(bdev->dev);
 848         if (ret < 0)
 849                 return ret;
 850
 851         if (srcs & BAM_IRQ) {
 852                 clr_mask = readl_relaxed(bam_addr(bdev, 0, BAM_IRQ_STTS));
 853
 854                 /*
 855                  * don't allow reorder of the various accesses to the BAM
 856                  * registers
 857                  */
 858                 mb();
 859
 860                 writel_relaxed(clr_mask, bam_addr(bdev, 0, BAM_IRQ_CLR));
 861         }
 862
 863         pm_runtime_mark_last_busy(bdev->dev);
 864         pm_runtime_put_autosuspend(bdev->dev);
 865
 866         return IRQ_HANDLED;
 867 }
 868
 869 /**
 870  * bam_tx_status - returns status of transaction
 871  * @chan: dma channel
 872  * @cookie: transaction cookie
 873  * @txstate: DMA transaction state
 874  *
 875  * Return status of dma transaction
 876  */
 877 static enum dma_status bam_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
 878                 struct dma_tx_state *txstate)
 879 {
 880         struct bam_chan *bchan = to_bam_chan(chan);
 881         struct virt_dma_desc *vd;
 882         int ret;
 883         size_t residue = 0;
 884         unsigned int i;
 885         unsigned long flags;
 886
 887         ret = dma_cookie_status(chan, cookie, txstate);
 888         if (ret == DMA_COMPLETE)
 889                 return ret;
 890
 891         if (!txstate)
 892                 return bchan->paused ? DMA_PAUSED : ret;
 893
 894         spin_lock_irqsave(&bchan->vc.lock, flags);
 895         vd = vchan_find_desc(&bchan->vc, cookie);
 896         if (vd)
 897                 residue = container_of(vd, struct bam_async_desc, vd)->length;
 898         else if (bchan->curr_txd && bchan->curr_txd->vd.tx.cookie == cookie)
 899                 for (i = 0; i < bchan->curr_txd->num_desc; i++)
 900                         residue += bchan->curr_txd->curr_desc[i].size;
 901
 902         spin_unlock_irqrestore(&bchan->vc.lock, flags);
 903
 904         dma_set_residue(txstate, residue);
 905
 906         if (ret == DMA_IN_PROGRESS && bchan->paused)
 907                 ret = DMA_PAUSED;
 908
 909         return ret;
 910 }
 911
 912 /**
 913  * bam_apply_new_config
 914  * @bchan: bam dma channel
 915  * @dir: DMA direction
 916  */
 917 static void bam_apply_new_config(struct bam_chan *bchan,
 918         enum dma_transfer_direction dir)
 919 {
 920         struct bam_device *bdev = bchan->bdev;
 921         u32 maxburst;
 922
 923         if (dir == DMA_DEV_TO_MEM)
 924                 maxburst = bchan->slave.src_maxburst;
 925         else
 926                 maxburst = bchan->slave.dst_maxburst;
 927
 928         writel_relaxed(maxburst, bam_addr(bdev, 0, BAM_DESC_CNT_TRSHLD));
 929
 930         bchan->reconfigure = 0;
 931 }
 932
 933 /**
 934  * bam_start_dma - start next transaction
 935  * @bchan - bam dma channel
 936  */
 937 static void bam_start_dma(struct bam_chan *bchan)
 938 {
 939         struct virt_dma_desc *vd = vchan_next_desc(&bchan->vc);
 940         struct bam_device *bdev = bchan->bdev;
 941         struct bam_async_desc *async_desc;
 942         struct bam_desc_hw *desc;
 943         struct bam_desc_hw *fifo = PTR_ALIGN(bchan->fifo_virt,
 944                                         sizeof(struct bam_desc_hw));
 945         int ret;
 946
 947         lockdep_assert_held(&bchan->vc.lock);
 948
 949         if (!vd)
 950                 return;
 951
 952         list_del(&vd->node);
 953
 954         async_desc = container_of(vd, struct bam_async_desc, vd);
 955         bchan->curr_txd = async_desc;
 956
 957         ret = pm_runtime_get_sync(bdev->dev);
 958         if (ret < 0)
 959                 return;
 960
 961         /* on first use, initialize the channel hardware */
 962         if (!bchan->initialized)
 963                 bam_chan_init_hw(bchan, async_desc->dir);
 964
 965         /* apply new slave config changes, if necessary */
 966         if (bchan->reconfigure)
 967                 bam_apply_new_config(bchan, async_desc->dir);
 968
 969         desc = bchan->curr_txd->curr_desc;
 970
 971         if (async_desc->num_desc > MAX_DESCRIPTORS)
 972                 async_desc->xfer_len = MAX_DESCRIPTORS;
 973         else
 974                 async_desc->xfer_len = async_desc->num_desc;
 975
 976         /* set any special flags on the last descriptor */
 977         if (async_desc->num_desc == async_desc->xfer_len)
 978                 desc[async_desc->xfer_len - 1].flags =
 979                                         cpu_to_le16(async_desc->flags);
 980         else
 981                 desc[async_desc->xfer_len - 1].flags |=
 982                                         cpu_to_le16(DESC_FLAG_INT);
 983
 984         if (bchan->tail + async_desc->xfer_len > MAX_DESCRIPTORS) {
 985                 u32 partial = MAX_DESCRIPTORS - bchan->tail;
 986
 987                 memcpy(&fifo[bchan->tail], desc,
 988                                 partial * sizeof(struct bam_desc_hw));
 989                 memcpy(fifo, &desc[partial], (async_desc->xfer_len - partial) *
 990                                 sizeof(struct bam_desc_hw));
 991         } else {
 992                 memcpy(&fifo[bchan->tail], desc,
 993                         async_desc->xfer_len * sizeof(struct bam_desc_hw));
 994         }
 995
 996         bchan->tail += async_desc->xfer_len;
 997         bchan->tail %= MAX_DESCRIPTORS;
 998
 999         /* ensure descriptor writes and dma start not reordered */
1000         wmb();
1001         writel_relaxed(bchan->tail * sizeof(struct bam_desc_hw),
1002                         bam_addr(bdev, bchan->id, BAM_P_EVNT_REG));
1003
1004         pm_runtime_mark_last_busy(bdev->dev);
1005         pm_runtime_put_autosuspend(bdev->dev);
1006 }
1007
1008 /**
1009  * dma_tasklet - DMA IRQ tasklet
1010  * @data: tasklet argument (bam controller structure)
1011  *
1012  * Sets up next DMA operation and then processes all completed transactions
1013  */
1014 static void dma_tasklet(unsigned long data)
1015 {
1016         struct bam_device *bdev = (struct bam_device *)data;
1017         struct bam_chan *bchan;
1018         unsigned long flags;
1019         unsigned int i;
1020
1021         /* go through the channels and kick off transactions */
1022         for (i = 0; i < bdev->num_channels; i++) {
1023                 bchan = &bdev->channels[i];
1024                 spin_lock_irqsave(&bchan->vc.lock, flags);
1025
1026                 if (!list_empty(&bchan->vc.desc_issued) && !bchan->curr_txd)
1027                         bam_start_dma(bchan);
1028                 spin_unlock_irqrestore(&bchan->vc.lock, flags);
1029         }
1030
1031 }
1032
1033 /**
1034  * bam_issue_pending - starts pending transactions
1035  * @chan: dma channel
1036  *
1037  * Calls tasklet directly which in turn starts any pending transactions
1038  */
1039 static void bam_issue_pending(struct dma_chan *chan)
1040 {
1041         struct bam_chan *bchan = to_bam_chan(chan);
1042         unsigned long flags;
1043
1044         spin_lock_irqsave(&bchan->vc.lock, flags);
1045
1046         /* if work pending and idle, start a transaction */
1047         if (vchan_issue_pending(&bchan->vc) && !bchan->curr_txd)
1048                 bam_start_dma(bchan);
1049
1050         spin_unlock_irqrestore(&bchan->vc.lock, flags);
1051 }
1052
1053 /**
1054  * bam_dma_free_desc - free descriptor memory
1055  * @vd: virtual descriptor
1056  *
1057  */
1058 static void bam_dma_free_desc(struct virt_dma_desc *vd)
1059 {
1060         struct bam_async_desc *async_desc = container_of(vd,
1061                         struct bam_async_desc, vd);
1062
1063         kfree(async_desc);
1064 }
1065
1066 static struct dma_chan *bam_dma_xlate(struct of_phandle_args *dma_spec,
1067                 struct of_dma *of)
1068 {
1069         struct bam_device *bdev = container_of(of->of_dma_data,
1070                                         struct bam_device, common);
1071         unsigned int request;
1072
1073         if (dma_spec->args_count != 1)
1074                 return NULL;
1075
1076         request = dma_spec->args[0];
1077         if (request >= bdev->num_channels)
1078                 return NULL;
1079
1080         return dma_get_slave_channel(&(bdev->channels[request].vc.chan));
1081 }
1082
1083 /**
1084  * bam_init
1085  * @bdev: bam device
1086  *
1087  * Initialization helper for global bam registers
1088  */
1089 static int bam_init(struct bam_device *bdev)
1090 {
1091         u32 val;
1092
1093         /* read revision and configuration information */
1094         if (!bdev->num_ees) {
1095                 val = readl_relaxed(bam_addr(bdev, 0, BAM_REVISION));
1096                 bdev->num_ees = (val >> NUM_EES_SHIFT) & NUM_EES_MASK;
1097         }
1098
1099         /* check that configured EE is within range */
1100         if (bdev->ee >= bdev->num_ees)
1101                 return -EINVAL;
1102
1103         if (!bdev->num_channels) {
1104                 val = readl_relaxed(bam_addr(bdev, 0, BAM_NUM_PIPES));
1105                 bdev->num_channels = val & BAM_NUM_PIPES_MASK;
1106         }
1107
1108         if (bdev->controlled_remotely)
1109                 return 0;
1110
1111         /* s/w reset bam */
1112         /* after reset all pipes are disabled and idle */
1113         val = readl_relaxed(bam_addr(bdev, 0, BAM_CTRL));
1114         val |= BAM_SW_RST;
1115         writel_relaxed(val, bam_addr(bdev, 0, BAM_CTRL));
1116         val &= ~BAM_SW_RST;
1117         writel_relaxed(val, bam_addr(bdev, 0, BAM_CTRL));
1118
1119         /* make sure previous stores are visible before enabling BAM */
1120         wmb();
1121
1122         /* enable bam */
1123         val |= BAM_EN;
1124         writel_relaxed(val, bam_addr(bdev, 0, BAM_CTRL));
1125
1126         /* set descriptor threshhold, start with 4 bytes */
1127         writel_relaxed(DEFAULT_CNT_THRSHLD,
1128                         bam_addr(bdev, 0, BAM_DESC_CNT_TRSHLD));
1129
1130         /* Enable default set of h/w workarounds, ie all except BAM_FULL_PIPE */
1131         writel_relaxed(BAM_CNFG_BITS_DEFAULT, bam_addr(bdev, 0, BAM_CNFG_BITS));
1132
1133         /* enable irqs for errors */
1134         writel_relaxed(BAM_ERROR_EN | BAM_HRESP_ERR_EN,
1135                         bam_addr(bdev, 0, BAM_IRQ_EN));
1136
1137         /* unmask global bam interrupt */
1138         writel_relaxed(BAM_IRQ_MSK, bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE));
1139
1140         return 0;
1141 }
1142
1143 static void bam_channel_init(struct bam_device *bdev, struct bam_chan *bchan,
1144         u32 index)
1145 {
1146         bchan->id = index;
1147         bchan->bdev = bdev;
1148
1149         vchan_init(&bchan->vc, &bdev->common);
1150         bchan->vc.desc_free = bam_dma_free_desc;
1151 }
1152
1153 static const struct of_device_id bam_of_match[] = {
1154         { .compatible = "qcom,bam-v1.3.0", .data = &bam_v1_3_reg_info },
1155         { .compatible = "qcom,bam-v1.4.0", .data = &bam_v1_4_reg_info },
1156         { .compatible = "qcom,bam-v1.7.0", .data = &bam_v1_7_reg_info },
1157         {}
1158 };
1159
1160 MODULE_DEVICE_TABLE(of, bam_of_match);
1161
1162 static int bam_dma_probe(struct platform_device *pdev)
1163 {
1164         struct bam_device *bdev;
1165         const struct of_device_id *match;
1166         struct resource *iores;
1167         int ret, i;
1168
1169         bdev = devm_kzalloc(&pdev->dev, sizeof(*bdev), GFP_KERNEL);
1170         if (!bdev)
1171                 return -ENOMEM;
1172
1173         bdev->dev = &pdev->dev;
1174
1175         match = of_match_node(bam_of_match, pdev->dev.of_node);
1176         if (!match) {
1177                 dev_err(&pdev->dev, "Unsupported BAM module\n");
1178                 return -ENODEV;
1179         }
1180
1181         bdev->layout = match->data;
1182
1183         iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1184         bdev->regs = devm_ioremap_resource(&pdev->dev, iores);
1185         if (IS_ERR(bdev->regs))
1186                 return PTR_ERR(bdev->regs);
1187
1188         bdev->irq = platform_get_irq(pdev, 0);
1189         if (bdev->irq < 0)
1190                 return bdev->irq;
1191
1192         ret = of_property_read_u32(pdev->dev.of_node, "qcom,ee", &bdev->ee);
1193         if (ret) {
1194                 dev_err(bdev->dev, "Execution environment unspecified\n");
1195                 return ret;
1196         }
1197
1198         bdev->controlled_remotely = of_property_read_bool(pdev->dev.of_node,
1199                                                 "qcom,controlled-remotely");
1200
1201         if (bdev->controlled_remotely) {
1202                 ret = of_property_read_u32(pdev->dev.of_node, "num-channels",
1203                                            &bdev->num_channels);
1204                 if (ret)
1205                         dev_err(bdev->dev, "num-channels unspecified in dt\n");
1206
1207                 ret = of_property_read_u32(pdev->dev.of_node, "qcom,num-ees",
1208                                            &bdev->num_ees);
1209                 if (ret)
1210                         dev_err(bdev->dev, "num-ees unspecified in dt\n");
1211         }
1212
1213         bdev->bamclk = devm_clk_get(bdev->dev, "bam_clk");
1214         if (IS_ERR(bdev->bamclk))
1215                 return PTR_ERR(bdev->bamclk);
1216
1217         ret = clk_prepare_enable(bdev->bamclk);
1218         if (ret) {
1219                 dev_err(bdev->dev, "failed to prepare/enable clock\n");
1220                 return ret;
1221         }
1222
1223         ret = bam_init(bdev);
1224         if (ret)
1225                 goto err_disable_clk;
1226
1227         tasklet_init(&bdev->task, dma_tasklet, (unsigned long)bdev);
1228
1229         bdev->channels = devm_kcalloc(bdev->dev, bdev->num_channels,
1230                                 sizeof(*bdev->channels), GFP_KERNEL);
1231
1232         if (!bdev->channels) {
1233                 ret = -ENOMEM;
1234                 goto err_tasklet_kill;
1235         }
1236
1237         /* allocate and initialize channels */
1238         INIT_LIST_HEAD(&bdev->common.channels);
1239
1240         for (i = 0; i < bdev->num_channels; i++)
1241                 bam_channel_init(bdev, &bdev->channels[i], i);
1242
1243         ret = devm_request_irq(bdev->dev, bdev->irq, bam_dma_irq,
1244                         IRQF_TRIGGER_HIGH, "bam_dma", bdev);
1245         if (ret)
1246                 goto err_bam_channel_exit;
1247
1248         /* set max dma segment size */
1249         bdev->common.dev = bdev->dev;
1250         bdev->common.dev->dma_parms = &bdev->dma_parms;
1251         ret = dma_set_max_seg_size(bdev->common.dev, BAM_FIFO_SIZE);
1252         if (ret) {
1253                 dev_err(bdev->dev, "cannot set maximum segment size\n");
1254                 goto err_bam_channel_exit;
1255         }
1256
1257         platform_set_drvdata(pdev, bdev);
1258
1259         /* set capabilities */
1260         dma_cap_zero(bdev->common.cap_mask);
1261         dma_cap_set(DMA_SLAVE, bdev->common.cap_mask);
1262
1263         /* initialize dmaengine apis */
1264         bdev->common.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
1265         bdev->common.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
1266         bdev->common.src_addr_widths = DMA_SLAVE_BUSWIDTH_4_BYTES;
1267         bdev->common.dst_addr_widths = DMA_SLAVE_BUSWIDTH_4_BYTES;
1268         bdev->common.device_alloc_chan_resources = bam_alloc_chan;
1269         bdev->common.device_free_chan_resources = bam_free_chan;
1270         bdev->common.device_prep_slave_sg = bam_prep_slave_sg;
1271         bdev->common.device_config = bam_slave_config;
1272         bdev->common.device_pause = bam_pause;
1273         bdev->common.device_resume = bam_resume;
1274         bdev->common.device_terminate_all = bam_dma_terminate_all;
1275         bdev->common.device_issue_pending = bam_issue_pending;
1276         bdev->common.device_tx_status = bam_tx_status;
1277         bdev->common.dev = bdev->dev;
1278
1279         ret = dma_async_device_register(&bdev->common);
1280         if (ret) {
1281                 dev_err(bdev->dev, "failed to register dma async device\n");
1282                 goto err_bam_channel_exit;
1283         }
1284
1285         ret = of_dma_controller_register(pdev->dev.of_node, bam_dma_xlate,
1286                                         &bdev->common);
1287         if (ret)
1288                 goto err_unregister_dma;
1289
1290         pm_runtime_irq_safe(&pdev->dev);
1291         pm_runtime_set_autosuspend_delay(&pdev->dev, BAM_DMA_AUTOSUSPEND_DELAY);
1292         pm_runtime_use_autosuspend(&pdev->dev);
1293         pm_runtime_mark_last_busy(&pdev->dev);
1294         pm_runtime_set_active(&pdev->dev);
1295         pm_runtime_enable(&pdev->dev);
1296
1297         return 0;
1298
1299 err_unregister_dma:
1300         dma_async_device_unregister(&bdev->common);
1301 err_bam_channel_exit:
1302         for (i = 0; i < bdev->num_channels; i++)
1303                 tasklet_kill(&bdev->channels[i].vc.task);
1304 err_tasklet_kill:
1305         tasklet_kill(&bdev->task);
1306 err_disable_clk:
1307         clk_disable_unprepare(bdev->bamclk);
1308
1309         return ret;
1310 }
1311
1312 static int bam_dma_remove(struct platform_device *pdev)
1313 {
1314         struct bam_device *bdev = platform_get_drvdata(pdev);
1315         u32 i;
1316
1317         pm_runtime_force_suspend(&pdev->dev);
1318
1319         of_dma_controller_free(pdev->dev.of_node);
1320         dma_async_device_unregister(&bdev->common);
1321
1322         /* mask all interrupts for this execution environment */
1323         writel_relaxed(0, bam_addr(bdev, 0,  BAM_IRQ_SRCS_MSK_EE));
1324
1325         devm_free_irq(bdev->dev, bdev->irq, bdev);
1326
1327         for (i = 0; i < bdev->num_channels; i++) {
1328                 bam_dma_terminate_all(&bdev->channels[i].vc.chan);
1329                 tasklet_kill(&bdev->channels[i].vc.task);
1330
1331                 if (!bdev->channels[i].fifo_virt)
1332                         continue;
1333
1334                 dma_free_wc(bdev->dev, BAM_DESC_FIFO_SIZE,
1335                             bdev->channels[i].fifo_virt,
1336                             bdev->channels[i].fifo_phys);
1337         }
1338
1339         tasklet_kill(&bdev->task);
1340
1341         clk_disable_unprepare(bdev->bamclk);
1342
1343         return 0;
1344 }
1345
1346 static int __maybe_unused bam_dma_runtime_suspend(struct device *dev)
1347 {
1348         struct bam_device *bdev = dev_get_drvdata(dev);
1349
1350         clk_disable(bdev->bamclk);
1351
1352         return 0;
1353 }
1354
1355 static int __maybe_unused bam_dma_runtime_resume(struct device *dev)
1356 {
1357         struct bam_device *bdev = dev_get_drvdata(dev);
1358         int ret;
1359
1360         ret = clk_enable(bdev->bamclk);
1361         if (ret < 0) {
1362                 dev_err(dev, "clk_enable failed: %d\n", ret);
1363                 return ret;
1364         }
1365
1366         return 0;
1367 }
1368
1369 static int __maybe_unused bam_dma_suspend(struct device *dev)
1370 {
1371         struct bam_device *bdev = dev_get_drvdata(dev);
1372
1373         pm_runtime_force_suspend(dev);
1374
1375         clk_unprepare(bdev->bamclk);
1376
1377         return 0;
1378 }
1379
1380 static int __maybe_unused bam_dma_resume(struct device *dev)
1381 {
1382         struct bam_device *bdev = dev_get_drvdata(dev);
1383         int ret;
1384
1385         ret = clk_prepare(bdev->bamclk);
1386         if (ret)
1387                 return ret;
1388
1389         pm_runtime_force_resume(dev);
1390
1391         return 0;
1392 }
1393
1394 static const struct dev_pm_ops bam_dma_pm_ops = {
1395         SET_LATE_SYSTEM_SLEEP_PM_OPS(bam_dma_suspend, bam_dma_resume)
1396         SET_RUNTIME_PM_OPS(bam_dma_runtime_suspend, bam_dma_runtime_resume,
1397                                 NULL)
1398 };
1399
1400 static struct platform_driver bam_dma_driver = {
1401         .probe = bam_dma_probe,
1402         .remove = bam_dma_remove,
1403         .driver = {
1404                 .name = "bam-dma-engine",
1405                 .pm = &bam_dma_pm_ops,
1406                 .of_match_table = bam_of_match,
1407         },
1408 };
1409
1410 module_platform_driver(bam_dma_driver);
1411
1412 MODULE_AUTHOR("Andy Gross <agross@codeaurora.org>");
1413 MODULE_DESCRIPTION("QCOM BAM DMA engine driver");
1414 MODULE_LICENSE("GPL v2");