// SPDX-License-Identifier: GPL-2.0-or-later
/* -*- linux-c -*- *
 *
 * ALSA driver for the digigram lx6464es interface
 * low-level interface
 *
 * Copyright (c) 2009 Tim Blechmann <tim@klingt.org>
 */

/* #define RMH_DEBUG 1 */

#include <linux/bitops.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/delay.h>

#include "lx6464es.h"
#include "lx_core.h"

/* low-level register access */

static const unsigned long dsp_port_offsets[] = {
        0,
        0x400,
        0x401,
        0x402,
        0x403,
        0x404,
        0x405,
        0x406,
        0x407,
        0x408,
        0x409,
        0x40a,
        0x40b,
        0x40c,

        0x410,
        0x411,
        0x412,
        0x413,
        0x414,
        0x415,
        0x416,

        0x420,
        0x430,
        0x431,
        0x432,
        0x433,
        0x434,
        0x440
};

static void __iomem *lx_dsp_register(struct lx6464es *chip, int port)
{
        void __iomem *base_address = chip->port_dsp_bar;
        return base_address + dsp_port_offsets[port]*4;
}

unsigned long lx_dsp_reg_read(struct lx6464es *chip, int port)
{
        void __iomem *address = lx_dsp_register(chip, port);
        return ioread32(address);
}

static void lx_dsp_reg_readbuf(struct lx6464es *chip, int port, u32 *data,
                               u32 len)
{
        u32 __iomem *address = lx_dsp_register(chip, port);
        int i;

        /* we cannot use memcpy_fromio */
        for (i = 0; i != len; ++i)
                data[i] = ioread32(address + i);
}


void lx_dsp_reg_write(struct lx6464es *chip, int port, unsigned data)
{
        void __iomem *address = lx_dsp_register(chip, port);
        iowrite32(data, address);
}

static void lx_dsp_reg_writebuf(struct lx6464es *chip, int port,
                                const u32 *data, u32 len)
{
        u32 __iomem *address = lx_dsp_register(chip, port);
        int i;

        /* we cannot use memcpy_to */
        for (i = 0; i != len; ++i)
                iowrite32(data[i], address + i);
}


static const unsigned long plx_port_offsets[] = {
        0x04,
        0x40,
        0x44,
        0x48,
        0x4c,
        0x50,
        0x54,
        0x58,
        0x5c,
        0x64,
        0x68,
        0x6C
};

static void __iomem *lx_plx_register(struct lx6464es *chip, int port)
{
        void __iomem *base_address = chip->port_plx_remapped;
        return base_address + plx_port_offsets[port];
}

unsigned long lx_plx_reg_read(struct lx6464es *chip, int port)
{
        void __iomem *address = lx_plx_register(chip, port);
        return ioread32(address);
}

void lx_plx_reg_write(struct lx6464es *chip, int port, u32 data)
{
        void __iomem *address = lx_plx_register(chip, port);
        iowrite32(data, address);
}

/* rmh */

#ifdef CONFIG_SND_DEBUG
#define CMD_NAME(a) a
#else
#define CMD_NAME(a) NULL
#endif

#define Reg_CSM_MR                      0x00000002
#define Reg_CSM_MC                      0x00000001

struct dsp_cmd_info {
        u32    dcCodeOp;        /* Op Code of the command (usually 1st 24-bits
                                 * word).*/
        u16    dcCmdLength;     /* Command length in words of 24 bits.*/
        u16    dcStatusType;    /* Status type: 0 for fixed length, 1 for
                                 * random. */
        u16    dcStatusLength;  /* Status length (if fixed).*/
        char  *dcOpName;
};

/*
  Initialization and control data for the Microblaze interface
  - OpCode:
    the opcode field of the command set at the proper offset
  - CmdLength
    the number of command words
  - StatusType
    offset in the status registers: 0 means that the return value may be
    different from 0, and must be read
  - StatusLength
    the number of status words (in addition to the return value)
*/

static struct dsp_cmd_info dsp_commands[] =
{
        { (CMD_00_INFO_DEBUG << OPCODE_OFFSET)                  , 1 /*custom*/
          , 1   , 0 /**/                    , CMD_NAME("INFO_DEBUG") },
        { (CMD_01_GET_SYS_CFG << OPCODE_OFFSET)                 , 1 /**/
          , 1      , 2 /**/                 , CMD_NAME("GET_SYS_CFG") },
        { (CMD_02_SET_GRANULARITY << OPCODE_OFFSET)             , 1 /**/
          , 1      , 0 /**/                 , CMD_NAME("SET_GRANULARITY") },
        { (CMD_03_SET_TIMER_IRQ << OPCODE_OFFSET)               , 1 /**/
          , 1      , 0 /**/                 , CMD_NAME("SET_TIMER_IRQ") },
        { (CMD_04_GET_EVENT << OPCODE_OFFSET)                   , 1 /**/
          , 1      , 0 /*up to 10*/     , CMD_NAME("GET_EVENT") },
        { (CMD_05_GET_PIPES << OPCODE_OFFSET)                   , 1 /**/
          , 1      , 2 /*up to 4*/      , CMD_NAME("GET_PIPES") },
        { (CMD_06_ALLOCATE_PIPE << OPCODE_OFFSET)               , 1 /**/
          , 0      , 0 /**/                 , CMD_NAME("ALLOCATE_PIPE") },
        { (CMD_07_RELEASE_PIPE << OPCODE_OFFSET)                , 1 /**/
          , 0      , 0 /**/                 , CMD_NAME("RELEASE_PIPE") },
        { (CMD_08_ASK_BUFFERS << OPCODE_OFFSET)                 , 1 /**/
          , 1      , MAX_STREAM_BUFFER  , CMD_NAME("ASK_BUFFERS") },
        { (CMD_09_STOP_PIPE << OPCODE_OFFSET)                   , 1 /**/
          , 0      , 0 /*up to 2*/      , CMD_NAME("STOP_PIPE") },
        { (CMD_0A_GET_PIPE_SPL_COUNT << OPCODE_OFFSET)          , 1 /**/
          , 1      , 1 /*up to 2*/      , CMD_NAME("GET_PIPE_SPL_COUNT") },
        { (CMD_0B_TOGGLE_PIPE_STATE << OPCODE_OFFSET)           , 1 /*up to 5*/
          , 1      , 0 /**/                 , CMD_NAME("TOGGLE_PIPE_STATE") },
        { (CMD_0C_DEF_STREAM << OPCODE_OFFSET)                  , 1 /*up to 4*/
          , 1      , 0 /**/                 , CMD_NAME("DEF_STREAM") },
        { (CMD_0D_SET_MUTE  << OPCODE_OFFSET)                   , 3 /**/
          , 1      , 0 /**/                 , CMD_NAME("SET_MUTE") },
        { (CMD_0E_GET_STREAM_SPL_COUNT << OPCODE_OFFSET)        , 1/**/
          , 1      , 2 /**/                 , CMD_NAME("GET_STREAM_SPL_COUNT") },
        { (CMD_0F_UPDATE_BUFFER << OPCODE_OFFSET)               , 3 /*up to 4*/
          , 0      , 1 /**/                 , CMD_NAME("UPDATE_BUFFER") },
        { (CMD_10_GET_BUFFER << OPCODE_OFFSET)                  , 1 /**/
          , 1      , 4 /**/                 , CMD_NAME("GET_BUFFER") },
        { (CMD_11_CANCEL_BUFFER << OPCODE_OFFSET)               , 1 /**/
          , 1      , 1 /*up to 4*/      , CMD_NAME("CANCEL_BUFFER") },
        { (CMD_12_GET_PEAK << OPCODE_OFFSET)                    , 1 /**/
          , 1      , 1 /**/                 , CMD_NAME("GET_PEAK") },
        { (CMD_13_SET_STREAM_STATE << OPCODE_OFFSET)            , 1 /**/
          , 1      , 0 /**/                 , CMD_NAME("SET_STREAM_STATE") },
};

static void lx_message_init(struct lx_rmh *rmh, enum cmd_mb_opcodes cmd)
{
        snd_BUG_ON(cmd >= CMD_14_INVALID);

        rmh->cmd[0] = dsp_commands[cmd].dcCodeOp;
        rmh->cmd_len = dsp_commands[cmd].dcCmdLength;
        rmh->stat_len = dsp_commands[cmd].dcStatusLength;
        rmh->dsp_stat = dsp_commands[cmd].dcStatusType;
        rmh->cmd_idx = cmd;
        memset(&rmh->cmd[1], 0, (REG_CRM_NUMBER - 1) * sizeof(u32));

#ifdef CONFIG_SND_DEBUG
        memset(rmh->stat, 0, REG_CRM_NUMBER * sizeof(u32));
#endif
#ifdef RMH_DEBUG
        rmh->cmd_idx = cmd;
#endif
}

#ifdef RMH_DEBUG
#define LXRMH "lx6464es rmh: "
static void lx_message_dump(struct lx_rmh *rmh)
{
        u8 idx = rmh->cmd_idx;
        int i;

        snd_printk(LXRMH "command %s\n", dsp_commands[idx].dcOpName);

        for (i = 0; i != rmh->cmd_len; ++i)
                snd_printk(LXRMH "\tcmd[%d] %08x\n", i, rmh->cmd[i]);

        for (i = 0; i != rmh->stat_len; ++i)
                snd_printk(LXRMH "\tstat[%d]: %08x\n", i, rmh->stat[i]);
        snd_printk("\n");
}
#else
static inline void lx_message_dump(struct lx_rmh *rmh)
{}
#endif



/* sleep 500 - 100 = 400 times 100us -> the timeout is >= 40 ms */
#define XILINX_TIMEOUT_MS       40
#define XILINX_POLL_NO_SLEEP    100
#define XILINX_POLL_ITERATIONS  150


static int lx_message_send_atomic(struct lx6464es *chip, struct lx_rmh *rmh)
{
        u32 reg = ED_DSP_TIMED_OUT;
        int dwloop;

        if (lx_dsp_reg_read(chip, eReg_CSM) & (Reg_CSM_MC | Reg_CSM_MR)) {
                dev_err(chip->card->dev, "PIOSendMessage eReg_CSM %x\n", reg);
                return -EBUSY;
        }

        /* write command */
        lx_dsp_reg_writebuf(chip, eReg_CRM1, rmh->cmd, rmh->cmd_len);

        /* MicoBlaze gogogo */
        lx_dsp_reg_write(chip, eReg_CSM, Reg_CSM_MC);

        /* wait for device to answer */
        for (dwloop = 0; dwloop != XILINX_TIMEOUT_MS * 1000; ++dwloop) {
                if (lx_dsp_reg_read(chip, eReg_CSM) & Reg_CSM_MR) {
                        if (rmh->dsp_stat == 0)
                                reg = lx_dsp_reg_read(chip, eReg_CRM1);
                        else
                                reg = 0;
                        goto polling_successful;
                } else
                        udelay(1);
        }
        dev_warn(chip->card->dev, "TIMEOUT lx_message_send_atomic! "
                   "polling failed\n");

polling_successful:
        if ((reg & ERROR_VALUE) == 0) {
                /* read response */
                if (rmh->stat_len) {
                        snd_BUG_ON(rmh->stat_len >= (REG_CRM_NUMBER-1));
                        lx_dsp_reg_readbuf(chip, eReg_CRM2, rmh->stat,
                                           rmh->stat_len);
                }
        } else
                dev_err(chip->card->dev, "rmh error: %08x\n", reg);

        /* clear Reg_CSM_MR */
        lx_dsp_reg_write(chip, eReg_CSM, 0);

        switch (reg) {
        case ED_DSP_TIMED_OUT:
                dev_warn(chip->card->dev, "lx_message_send: dsp timeout\n");
                return -ETIMEDOUT;

        case ED_DSP_CRASHED:
                dev_warn(chip->card->dev, "lx_message_send: dsp crashed\n");
                return -EAGAIN;
        }

        lx_message_dump(rmh);

        return reg;
}


/* low-level dsp access */
int lx_dsp_get_version(struct lx6464es *chip, u32 *rdsp_version)
{
        u16 ret;

        mutex_lock(&chip->msg_lock);

        lx_message_init(&chip->rmh, CMD_01_GET_SYS_CFG);
        ret = lx_message_send_atomic(chip, &chip->rmh);

        *rdsp_version = chip->rmh.stat[1];
        mutex_unlock(&chip->msg_lock);
        return ret;
}

int lx_dsp_get_clock_frequency(struct lx6464es *chip, u32 *rfreq)
{
        u16 ret = 0;
        u32 freq_raw = 0;
        u32 freq = 0;
        u32 frequency = 0;

        mutex_lock(&chip->msg_lock);

        lx_message_init(&chip->rmh, CMD_01_GET_SYS_CFG);
        ret = lx_message_send_atomic(chip, &chip->rmh);

        if (ret == 0) {
                freq_raw = chip->rmh.stat[0] >> FREQ_FIELD_OFFSET;
                freq = freq_raw & XES_FREQ_COUNT8_MASK;

                if ((freq < XES_FREQ_COUNT8_48_MAX) ||
                    (freq > XES_FREQ_COUNT8_44_MIN))
                        frequency = 0; /* unknown */
                else if (freq >= XES_FREQ_COUNT8_44_MAX)
                        frequency = 44100;
                else
                        frequency = 48000;
        }

        mutex_unlock(&chip->msg_lock);

        *rfreq = frequency * chip->freq_ratio;

        return ret;
}

int lx_dsp_get_mac(struct lx6464es *chip)
{
        u32 macmsb, maclsb;

        macmsb = lx_dsp_reg_read(chip, eReg_ADMACESMSB) & 0x00FFFFFF;
        maclsb = lx_dsp_reg_read(chip, eReg_ADMACESLSB) & 0x00FFFFFF;

        /* todo: endianess handling */
        chip->mac_address[5] = ((u8 *)(&maclsb))[0];
        chip->mac_address[4] = ((u8 *)(&maclsb))[1];
        chip->mac_address[3] = ((u8 *)(&maclsb))[2];
        chip->mac_address[2] = ((u8 *)(&macmsb))[0];
        chip->mac_address[1] = ((u8 *)(&macmsb))[1];
        chip->mac_address[0] = ((u8 *)(&macmsb))[2];

        return 0;
}


int lx_dsp_set_granularity(struct lx6464es *chip, u32 gran)
{
        int ret;

        mutex_lock(&chip->msg_lock);

        lx_message_init(&chip->rmh, CMD_02_SET_GRANULARITY);
        chip->rmh.cmd[0] |= gran;

        ret = lx_message_send_atomic(chip, &chip->rmh);
        mutex_unlock(&chip->msg_lock);
        return ret;
}

int lx_dsp_read_async_events(struct lx6464es *chip, u32 *data)
{
        int ret;

        mutex_lock(&chip->msg_lock);

        lx_message_init(&chip->rmh, CMD_04_GET_EVENT);
        chip->rmh.stat_len = 9; /* we don't necessarily need the full length */

        ret = lx_message_send_atomic(chip, &chip->rmh);

        if (!ret)
                memcpy(data, chip->rmh.stat, chip->rmh.stat_len * sizeof(u32));

        mutex_unlock(&chip->msg_lock);
        return ret;
}

#define PIPE_INFO_TO_CMD(capture, pipe)                                 \
        ((u32)((u32)(pipe) | ((capture) ? ID_IS_CAPTURE : 0L)) << ID_OFFSET)



/* low-level pipe handling */
int lx_pipe_allocate(struct lx6464es *chip, u32 pipe, int is_capture,
                     int channels)
{
        int err;
        u32 pipe_cmd = PIPE_INFO_TO_CMD(is_capture, pipe);

        mutex_lock(&chip->msg_lock);
        lx_message_init(&chip->rmh, CMD_06_ALLOCATE_PIPE);

        chip->rmh.cmd[0] |= pipe_cmd;
        chip->rmh.cmd[0] |= channels;

        err = lx_message_send_atomic(chip, &chip->rmh);
        mutex_unlock(&chip->msg_lock);

        if (err != 0)
                dev_err(chip->card->dev, "could not allocate pipe\n");

        return err;
}

int lx_pipe_release(struct lx6464es *chip, u32 pipe, int is_capture)
{
        int err;
        u32 pipe_cmd = PIPE_INFO_TO_CMD(is_capture, pipe);

        mutex_lock(&chip->msg_lock);
        lx_message_init(&chip->rmh, CMD_07_RELEASE_PIPE);

        chip->rmh.cmd[0] |= pipe_cmd;

        err = lx_message_send_atomic(chip, &chip->rmh);
        mutex_unlock(&chip->msg_lock);

        return err;
}

int lx_buffer_ask(struct lx6464es *chip, u32 pipe, int is_capture,
                  u32 *r_needed, u32 *r_freed, u32 *size_array)
{
        int err;
        u32 pipe_cmd = PIPE_INFO_TO_CMD(is_capture, pipe);

#ifdef CONFIG_SND_DEBUG
        if (size_array)
                memset(size_array, 0, sizeof(u32)*MAX_STREAM_BUFFER);
#endif

        *r_needed = 0;
        *r_freed = 0;

        mutex_lock(&chip->msg_lock);
        lx_message_init(&chip->rmh, CMD_08_ASK_BUFFERS);

        chip->rmh.cmd[0] |= pipe_cmd;

        err = lx_message_send_atomic(chip, &chip->rmh);

        if (!err) {
                int i;
                for (i = 0; i < MAX_STREAM_BUFFER; ++i) {
                        u32 stat = chip->rmh.stat[i];
                        if (stat & (BF_EOB << BUFF_FLAGS_OFFSET)) {
                                /* finished */
                                *r_freed += 1;
                                if (size_array)
                                        size_array[i] = stat & MASK_DATA_SIZE;
                        } else if ((stat & (BF_VALID << BUFF_FLAGS_OFFSET))
                                   == 0)
                                /* free */
                                *r_needed += 1;
                }

                dev_dbg(chip->card->dev,
                        "CMD_08_ASK_BUFFERS: needed %d, freed %d\n",
                            *r_needed, *r_freed);
                for (i = 0; i < MAX_STREAM_BUFFER; ++i) {
                        for (i = 0; i != chip->rmh.stat_len; ++i)
                                dev_dbg(chip->card->dev,
                                        "  stat[%d]: %x, %x\n", i,
                                            chip->rmh.stat[i],
                                            chip->rmh.stat[i] & MASK_DATA_SIZE);
                }
        }

        mutex_unlock(&chip->msg_lock);
        return err;
}


int lx_pipe_stop(struct lx6464es *chip, u32 pipe, int is_capture)
{
        int err;
        u32 pipe_cmd = PIPE_INFO_TO_CMD(is_capture, pipe);

        mutex_lock(&chip->msg_lock);
        lx_message_init(&chip->rmh, CMD_09_STOP_PIPE);

        chip->rmh.cmd[0] |= pipe_cmd;

        err = lx_message_send_atomic(chip, &chip->rmh);

        mutex_unlock(&chip->msg_lock);
        return err;
}

static int lx_pipe_toggle_state(struct lx6464es *chip, u32 pipe, int is_capture)
{
        int err;
        u32 pipe_cmd = PIPE_INFO_TO_CMD(is_capture, pipe);

        mutex_lock(&chip->msg_lock);
        lx_message_init(&chip->rmh, CMD_0B_TOGGLE_PIPE_STATE);

        chip->rmh.cmd[0] |= pipe_cmd;

        err = lx_message_send_atomic(chip, &chip->rmh);

        mutex_unlock(&chip->msg_lock);
        return err;
}


int lx_pipe_start(struct lx6464es *chip, u32 pipe, int is_capture)
{
        int err;

        err = lx_pipe_wait_for_idle(chip, pipe, is_capture);
        if (err < 0)
                return err;

        err = lx_pipe_toggle_state(chip, pipe, is_capture);

        return err;
}

int lx_pipe_pause(struct lx6464es *chip, u32 pipe, int is_capture)
{
        int err = 0;

        err = lx_pipe_wait_for_start(chip, pipe, is_capture);
        if (err < 0)
                return err;

        err = lx_pipe_toggle_state(chip, pipe, is_capture);

        return err;
}


int lx_pipe_sample_count(struct lx6464es *chip, u32 pipe, int is_capture,
                         u64 *rsample_count)
{
        int err;
        u32 pipe_cmd = PIPE_INFO_TO_CMD(is_capture, pipe);

        mutex_lock(&chip->msg_lock);
        lx_message_init(&chip->rmh, CMD_0A_GET_PIPE_SPL_COUNT);

        chip->rmh.cmd[0] |= pipe_cmd;
        chip->rmh.stat_len = 2; /* need all words here! */

        err = lx_message_send_atomic(chip, &chip->rmh); /* don't sleep! */

        if (err != 0)
                dev_err(chip->card->dev,
                        "could not query pipe's sample count\n");
        else {
                *rsample_count = ((u64)(chip->rmh.stat[0] & MASK_SPL_COUNT_HI)
                                  << 24)     /* hi part */
                        + chip->rmh.stat[1]; /* lo part */
        }

        mutex_unlock(&chip->msg_lock);
        return err;
}

int lx_pipe_state(struct lx6464es *chip, u32 pipe, int is_capture, u16 *rstate)
{
        int err;
        u32 pipe_cmd = PIPE_INFO_TO_CMD(is_capture, pipe);

        mutex_lock(&chip->msg_lock);
        lx_message_init(&chip->rmh, CMD_0A_GET_PIPE_SPL_COUNT);

        chip->rmh.cmd[0] |= pipe_cmd;

        err = lx_message_send_atomic(chip, &chip->rmh);

        if (err != 0)
                dev_err(chip->card->dev, "could not query pipe's state\n");
        else
                *rstate = (chip->rmh.stat[0] >> PSTATE_OFFSET) & 0x0F;

        mutex_unlock(&chip->msg_lock);
        return err;
}

static int lx_pipe_wait_for_state(struct lx6464es *chip, u32 pipe,
                                  int is_capture, u16 state)
{
        int i;

        /* max 2*PCMOnlyGranularity = 2*1024 at 44100 = < 50 ms:
         * timeout 50 ms */
        for (i = 0; i != 50; ++i) {
                u16 current_state;
                int err = lx_pipe_state(chip, pipe, is_capture, &current_state);

                if (err < 0)
                        return err;

                if (!err && current_state == state)
                        return 0;

                mdelay(1);
        }

        return -ETIMEDOUT;
}

int lx_pipe_wait_for_start(struct lx6464es *chip, u32 pipe, int is_capture)
{
        return lx_pipe_wait_for_state(chip, pipe, is_capture, PSTATE_RUN);
}

int lx_pipe_wait_for_idle(struct lx6464es *chip, u32 pipe, int is_capture)
{
        return lx_pipe_wait_for_state(chip, pipe, is_capture, PSTATE_IDLE);
}

/* low-level stream handling */
int lx_stream_set_state(struct lx6464es *chip, u32 pipe,
                               int is_capture, enum stream_state_t state)
{
        int err;
        u32 pipe_cmd = PIPE_INFO_TO_CMD(is_capture, pipe);

        mutex_lock(&chip->msg_lock);
        lx_message_init(&chip->rmh, CMD_13_SET_STREAM_STATE);

        chip->rmh.cmd[0] |= pipe_cmd;
        chip->rmh.cmd[0] |= state;

        err = lx_message_send_atomic(chip, &chip->rmh);
        mutex_unlock(&chip->msg_lock);

        return err;
}

int lx_stream_set_format(struct lx6464es *chip, struct snd_pcm_runtime *runtime,
                         u32 pipe, int is_capture)
{
        int err;
        u32 pipe_cmd = PIPE_INFO_TO_CMD(is_capture, pipe);
        u32 channels = runtime->channels;

        if (runtime->channels != channels)
                dev_err(chip->card->dev, "channel count mismatch: %d vs %d",
                           runtime->channels, channels);

        mutex_lock(&chip->msg_lock);
        lx_message_init(&chip->rmh, CMD_0C_DEF_STREAM);

        chip->rmh.cmd[0] |= pipe_cmd;

        if (runtime->sample_bits == 16)
                /* 16 bit format */
                chip->rmh.cmd[0] |= (STREAM_FMT_16b << STREAM_FMT_OFFSET);

        if (snd_pcm_format_little_endian(runtime->format))
                /* little endian/intel format */
                chip->rmh.cmd[0] |= (STREAM_FMT_intel << STREAM_FMT_OFFSET);

        chip->rmh.cmd[0] |= channels-1;

        err = lx_message_send_atomic(chip, &chip->rmh);
        mutex_unlock(&chip->msg_lock);

        return err;
}

int lx_stream_state(struct lx6464es *chip, u32 pipe, int is_capture,
                    int *rstate)
{
        int err;
        u32 pipe_cmd = PIPE_INFO_TO_CMD(is_capture, pipe);

        mutex_lock(&chip->msg_lock);
        lx_message_init(&chip->rmh, CMD_0E_GET_STREAM_SPL_COUNT);

        chip->rmh.cmd[0] |= pipe_cmd;

        err = lx_message_send_atomic(chip, &chip->rmh);

        *rstate = (chip->rmh.stat[0] & SF_START) ? START_STATE : PAUSE_STATE;

        mutex_unlock(&chip->msg_lock);
        return err;
}

int lx_stream_sample_position(struct lx6464es *chip, u32 pipe, int is_capture,
                              u64 *r_bytepos)
{
        int err;
        u32 pipe_cmd = PIPE_INFO_TO_CMD(is_capture, pipe);

        mutex_lock(&chip->msg_lock);
        lx_message_init(&chip->rmh, CMD_0E_GET_STREAM_SPL_COUNT);

        chip->rmh.cmd[0] |= pipe_cmd;

        err = lx_message_send_atomic(chip, &chip->rmh);

        *r_bytepos = ((u64) (chip->rmh.stat[0] & MASK_SPL_COUNT_HI)
                      << 32)         /* hi part */
                + chip->rmh.stat[1]; /* lo part */

        mutex_unlock(&chip->msg_lock);
        return err;
}

/* low-level buffer handling */
int lx_buffer_give(struct lx6464es *chip, u32 pipe, int is_capture,
                   u32 buffer_size, u32 buf_address_lo, u32 buf_address_hi,
                   u32 *r_buffer_index)
{
        int err;
        u32 pipe_cmd = PIPE_INFO_TO_CMD(is_capture, pipe);

        mutex_lock(&chip->msg_lock);
        lx_message_init(&chip->rmh, CMD_0F_UPDATE_BUFFER);

        chip->rmh.cmd[0] |= pipe_cmd;
        chip->rmh.cmd[0] |= BF_NOTIFY_EOB; /* request interrupt notification */

        /* todo: pause request, circular buffer */

        chip->rmh.cmd[1] = buffer_size & MASK_DATA_SIZE;
        chip->rmh.cmd[2] = buf_address_lo;

        if (buf_address_hi) {
                chip->rmh.cmd_len = 4;
                chip->rmh.cmd[3] = buf_address_hi;
                chip->rmh.cmd[0] |= BF_64BITS_ADR;
        }

        err = lx_message_send_atomic(chip, &chip->rmh);

        if (err == 0) {
                *r_buffer_index = chip->rmh.stat[0];
                goto done;
        }

        if (err == EB_RBUFFERS_TABLE_OVERFLOW)
                dev_err(chip->card->dev,
                        "lx_buffer_give EB_RBUFFERS_TABLE_OVERFLOW\n");

        if (err == EB_INVALID_STREAM)
                dev_err(chip->card->dev,
                        "lx_buffer_give EB_INVALID_STREAM\n");

        if (err == EB_CMD_REFUSED)
                dev_err(chip->card->dev,
                        "lx_buffer_give EB_CMD_REFUSED\n");

 done:
        mutex_unlock(&chip->msg_lock);
        return err;
}

int lx_buffer_free(struct lx6464es *chip, u32 pipe, int is_capture,
                   u32 *r_buffer_size)
{
        int err;
        u32 pipe_cmd = PIPE_INFO_TO_CMD(is_capture, pipe);

        mutex_lock(&chip->msg_lock);
        lx_message_init(&chip->rmh, CMD_11_CANCEL_BUFFER);

        chip->rmh.cmd[0] |= pipe_cmd;
        chip->rmh.cmd[0] |= MASK_BUFFER_ID; /* ask for the current buffer: the
                                             * microblaze will seek for it */

        err = lx_message_send_atomic(chip, &chip->rmh);

        if (err == 0)
                *r_buffer_size = chip->rmh.stat[0]  & MASK_DATA_SIZE;

        mutex_unlock(&chip->msg_lock);
        return err;
}

int lx_buffer_cancel(struct lx6464es *chip, u32 pipe, int is_capture,
                     u32 buffer_index)
{
        int err;
        u32 pipe_cmd = PIPE_INFO_TO_CMD(is_capture, pipe);

        mutex_lock(&chip->msg_lock);
        lx_message_init(&chip->rmh, CMD_11_CANCEL_BUFFER);

        chip->rmh.cmd[0] |= pipe_cmd;
        chip->rmh.cmd[0] |= buffer_index;

        err = lx_message_send_atomic(chip, &chip->rmh);

        mutex_unlock(&chip->msg_lock);
        return err;
}


/* low-level gain/peak handling
 *
 * \todo: can we unmute capture/playback channels independently?
 *
 * */
int lx_level_unmute(struct lx6464es *chip, int is_capture, int unmute)
{
        int err;
        /* bit set to 1: channel muted */
        u64 mute_mask = unmute ? 0 : 0xFFFFFFFFFFFFFFFFLLU;

        mutex_lock(&chip->msg_lock);
        lx_message_init(&chip->rmh, CMD_0D_SET_MUTE);

        chip->rmh.cmd[0] |= PIPE_INFO_TO_CMD(is_capture, 0);

        chip->rmh.cmd[1] = (u32)(mute_mask >> (u64)32);        /* hi part */
        chip->rmh.cmd[2] = (u32)(mute_mask & (u64)0xFFFFFFFF); /* lo part */

        dev_dbg(chip->card->dev,
                "mute %x %x %x\n", chip->rmh.cmd[0], chip->rmh.cmd[1],
                   chip->rmh.cmd[2]);

        err = lx_message_send_atomic(chip, &chip->rmh);

        mutex_unlock(&chip->msg_lock);
        return err;
}

static u32 peak_map[] = {
        0x00000109, /* -90.308dB */
        0x0000083B, /* -72.247dB */
        0x000020C4, /* -60.205dB */
        0x00008273, /* -48.030dB */
        0x00020756, /* -36.005dB */
        0x00040C37, /* -30.001dB */
        0x00081385, /* -24.002dB */
        0x00101D3F, /* -18.000dB */
        0x0016C310, /* -15.000dB */
        0x002026F2, /* -12.001dB */
        0x002D6A86, /* -9.000dB */
        0x004026E6, /* -6.004dB */
        0x005A9DF6, /* -3.000dB */
        0x0065AC8B, /* -2.000dB */
        0x00721481, /* -1.000dB */
        0x007FFFFF, /* FS */
};

int lx_level_peaks(struct lx6464es *chip, int is_capture, int channels,
                   u32 *r_levels)
{
        int err = 0;
        int i;

        mutex_lock(&chip->msg_lock);
        for (i = 0; i < channels; i += 4) {
                u32 s0, s1, s2, s3;

                lx_message_init(&chip->rmh, CMD_12_GET_PEAK);
                chip->rmh.cmd[0] |= PIPE_INFO_TO_CMD(is_capture, i);

                err = lx_message_send_atomic(chip, &chip->rmh);

                if (err == 0) {
                        s0 = peak_map[chip->rmh.stat[0] & 0x0F];
                        s1 = peak_map[(chip->rmh.stat[0] >>  4) & 0xf];
                        s2 = peak_map[(chip->rmh.stat[0] >>  8) & 0xf];
                        s3 = peak_map[(chip->rmh.stat[0] >>  12) & 0xf];
                } else
                        s0 = s1 = s2 = s3 = 0;

                r_levels[0] = s0;
                r_levels[1] = s1;
                r_levels[2] = s2;
                r_levels[3] = s3;

                r_levels += 4;
        }

        mutex_unlock(&chip->msg_lock);
        return err;
}

/* interrupt handling */
#define PCX_IRQ_NONE 0
#define IRQCS_ACTIVE_PCIDB      BIT(13)
#define IRQCS_ENABLE_PCIIRQ     BIT(8)
#define IRQCS_ENABLE_PCIDB      BIT(9)

static u32 lx_interrupt_test_ack(struct lx6464es *chip)
{
        u32 irqcs = lx_plx_reg_read(chip, ePLX_IRQCS);

        /* Test if PCI Doorbell interrupt is active */
        if (irqcs & IRQCS_ACTIVE_PCIDB) {
                u32 temp;
                irqcs = PCX_IRQ_NONE;

                while ((temp = lx_plx_reg_read(chip, ePLX_L2PCIDB))) {
                        /* RAZ interrupt */
                        irqcs |= temp;
                        lx_plx_reg_write(chip, ePLX_L2PCIDB, temp);
                }

                return irqcs;
        }
        return PCX_IRQ_NONE;
}

static int lx_interrupt_ack(struct lx6464es *chip, u32 *r_irqsrc,
                            int *r_async_pending, int *r_async_escmd)
{
        u32 irq_async;
        u32 irqsrc = lx_interrupt_test_ack(chip);

        if (irqsrc == PCX_IRQ_NONE)
                return 0;

        *r_irqsrc = irqsrc;

        irq_async = irqsrc & MASK_SYS_ASYNC_EVENTS; /* + EtherSound response
                                                     * (set by xilinx) + EOB */

        if (irq_async & MASK_SYS_STATUS_ESA) {
                irq_async &= ~MASK_SYS_STATUS_ESA;
                *r_async_escmd = 1;
        }

        if (irq_async) {
                /* dev_dbg(chip->card->dev, "interrupt: async event pending\n"); */
                *r_async_pending = 1;
        }

        return 1;
}

static int lx_interrupt_handle_async_events(struct lx6464es *chip, u32 irqsrc,
                                            int *r_freq_changed,
                                            u64 *r_notified_in_pipe_mask,
                                            u64 *r_notified_out_pipe_mask)
{
        int err;
        u32 stat[9];            /* answer from CMD_04_GET_EVENT */

        /* We can optimize this to not read dumb events.
         * Answer words are in the following order:
         * Stat[0]      general status
         * Stat[1]      end of buffer OUT pF
         * Stat[2]      end of buffer OUT pf
         * Stat[3]      end of buffer IN pF
         * Stat[4]      end of buffer IN pf
         * Stat[5]      MSB underrun
         * Stat[6]      LSB underrun
         * Stat[7]      MSB overrun
         * Stat[8]      LSB overrun
         * */

        int eb_pending_out = (irqsrc & MASK_SYS_STATUS_EOBO) ? 1 : 0;
        int eb_pending_in  = (irqsrc & MASK_SYS_STATUS_EOBI) ? 1 : 0;

        *r_freq_changed = (irqsrc & MASK_SYS_STATUS_FREQ) ? 1 : 0;

        err = lx_dsp_read_async_events(chip, stat);
        if (err < 0)
                return err;

        if (eb_pending_in) {
                *r_notified_in_pipe_mask = ((u64)stat[3] << 32)
                        + stat[4];

                dev_dbg(chip->card->dev, "interrupt: EOBI pending %llx\n",
                            *r_notified_in_pipe_mask);
        }
        if (eb_pending_out) {
                *r_notified_out_pipe_mask = ((u64)stat[1] << 32)
                        + stat[2];
                dev_dbg(chip->card->dev, "interrupt: EOBO pending %llx\n",
                            *r_notified_out_pipe_mask);
        }

        /* todo: handle xrun notification */

        return err;
}

static int lx_interrupt_request_new_buffer(struct lx6464es *chip,
                                           struct lx_stream *lx_stream)
{
        struct snd_pcm_substream *substream = lx_stream->stream;
        const unsigned int is_capture = lx_stream->is_capture;
        int err;

        const u32 channels = substream->runtime->channels;
        const u32 bytes_per_frame = channels * 3;
        const u32 period_size = substream->runtime->period_size;
        const u32 period_bytes = period_size * bytes_per_frame;
        const u32 pos = lx_stream->frame_pos;
        const u32 next_pos = ((pos+1) == substream->runtime->periods) ?
                0 : pos + 1;

        dma_addr_t buf = substream->dma_buffer.addr + pos * period_bytes;
        u32 buf_hi = 0;
        u32 buf_lo = 0;
        u32 buffer_index = 0;

        u32 needed, freed;
        u32 size_array[MAX_STREAM_BUFFER];

        dev_dbg(chip->card->dev, "->lx_interrupt_request_new_buffer\n");

        mutex_lock(&chip->lock);

        err = lx_buffer_ask(chip, 0, is_capture, &needed, &freed, size_array);
        dev_dbg(chip->card->dev,
                "interrupt: needed %d, freed %d\n", needed, freed);

        unpack_pointer(buf, &buf_lo, &buf_hi);
        err = lx_buffer_give(chip, 0, is_capture, period_bytes, buf_lo, buf_hi,
                             &buffer_index);
        dev_dbg(chip->card->dev,
                "interrupt: gave buffer index %x on 0x%lx (%d bytes)\n",
                    buffer_index, (unsigned long)buf, period_bytes);

        lx_stream->frame_pos = next_pos;
        mutex_unlock(&chip->lock);

        return err;
}

irqreturn_t lx_interrupt(int irq, void *dev_id)
{
        struct lx6464es *chip = dev_id;
        int async_pending, async_escmd;
        u32 irqsrc;
        bool wake_thread = false;

        dev_dbg(chip->card->dev,
                "**************************************************\n");

        if (!lx_interrupt_ack(chip, &irqsrc, &async_pending, &async_escmd)) {
                dev_dbg(chip->card->dev, "IRQ_NONE\n");
                return IRQ_NONE; /* this device did not cause the interrupt */
        }

        if (irqsrc & MASK_SYS_STATUS_CMD_DONE)
                return IRQ_HANDLED;

        if (irqsrc & MASK_SYS_STATUS_EOBI)
                dev_dbg(chip->card->dev, "interrupt: EOBI\n");

        if (irqsrc & MASK_SYS_STATUS_EOBO)
                dev_dbg(chip->card->dev, "interrupt: EOBO\n");

        if (irqsrc & MASK_SYS_STATUS_URUN)
                dev_dbg(chip->card->dev, "interrupt: URUN\n");

        if (irqsrc & MASK_SYS_STATUS_ORUN)
                dev_dbg(chip->card->dev, "interrupt: ORUN\n");

        if (async_pending) {
                wake_thread = true;
                chip->irqsrc = irqsrc;
        }

        if (async_escmd) {
                /* backdoor for ethersound commands
                 *
                 * for now, we do not need this
                 *
                 * */

                dev_dbg(chip->card->dev, "interrupt requests escmd handling\n");
        }

        return wake_thread ? IRQ_WAKE_THREAD : IRQ_HANDLED;
}

irqreturn_t lx_threaded_irq(int irq, void *dev_id)
{
        struct lx6464es *chip = dev_id;
        u64 notified_in_pipe_mask = 0;
        u64 notified_out_pipe_mask = 0;
        int freq_changed;
        int err;

        /* handle async events */
        err = lx_interrupt_handle_async_events(chip, chip->irqsrc,
                                               &freq_changed,
                                               &notified_in_pipe_mask,
                                               &notified_out_pipe_mask);
        if (err)
                dev_err(chip->card->dev, "error handling async events\n");

        if (notified_in_pipe_mask) {
                struct lx_stream *lx_stream = &chip->capture_stream;

                dev_dbg(chip->card->dev,
                        "requesting audio transfer for capture\n");
                err = lx_interrupt_request_new_buffer(chip, lx_stream);
                if (err < 0)
                        dev_err(chip->card->dev,
                                "cannot request new buffer for capture\n");
                snd_pcm_period_elapsed(lx_stream->stream);
        }

        if (notified_out_pipe_mask) {
                struct lx_stream *lx_stream = &chip->playback_stream;

                dev_dbg(chip->card->dev,
                        "requesting audio transfer for playback\n");
                err = lx_interrupt_request_new_buffer(chip, lx_stream);
                if (err < 0)
                        dev_err(chip->card->dev,
                                "cannot request new buffer for playback\n");
                snd_pcm_period_elapsed(lx_stream->stream);
        }

        return IRQ_HANDLED;
}


static void lx_irq_set(struct lx6464es *chip, int enable)
{
        u32 reg = lx_plx_reg_read(chip, ePLX_IRQCS);

        /* enable/disable interrupts
         *
         * Set the Doorbell and PCI interrupt enable bits
         *
         * */
        if (enable)
                reg |=  (IRQCS_ENABLE_PCIIRQ | IRQCS_ENABLE_PCIDB);
        else
                reg &= ~(IRQCS_ENABLE_PCIIRQ | IRQCS_ENABLE_PCIDB);
        lx_plx_reg_write(chip, ePLX_IRQCS, reg);
}

void lx_irq_enable(struct lx6464es *chip)
{
        dev_dbg(chip->card->dev, "->lx_irq_enable\n");
        lx_irq_set(chip, 1);
}

void lx_irq_disable(struct lx6464es *chip)
{
        dev_dbg(chip->card->dev, "->lx_irq_disable\n");
        lx_irq_set(chip, 0);
}