// SPDX-License-Identifier: GPL-2.0-only
/*
 * Driver for MPC52xx processor BestComm General Buffer Descriptor
 *
 * Copyright (C) 2007 Sylvain Munaut <tnt@246tNt.com>
 * Copyright (C) 2006 AppSpec Computer Technologies Corp.
 *                    Jeff Gibbons <jeff.gibbons@appspec.com>
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/types.h>
#include <asm/errno.h>
#include <asm/io.h>

#include <asm/mpc52xx.h>
#include <asm/mpc52xx_psc.h>

#include <linux/fsl/bestcomm/bestcomm.h>
#include <linux/fsl/bestcomm/bestcomm_priv.h>
#include <linux/fsl/bestcomm/gen_bd.h>


/* ======================================================================== */
/* Task image/var/inc                                                       */
/* ======================================================================== */

/* gen_bd tasks images */
extern u32 bcom_gen_bd_rx_task[];
extern u32 bcom_gen_bd_tx_task[];

/* rx task vars that need to be set before enabling the task */
struct bcom_gen_bd_rx_var {
        u32 enable;             /* (u16*) address of task's control register */
        u32 fifo;               /* (u32*) address of gen_bd's fifo */
        u32 bd_base;            /* (struct bcom_bd*) beginning of ring buffer */
        u32 bd_last;            /* (struct bcom_bd*) end of ring buffer */
        u32 bd_start;           /* (struct bcom_bd*) current bd */
        u32 buffer_size;        /* size of receive buffer */
};

/* rx task incs that need to be set before enabling the task */
struct bcom_gen_bd_rx_inc {
        u16 pad0;
        s16 incr_bytes;
        u16 pad1;
        s16 incr_dst;
};

/* tx task vars that need to be set before enabling the task */
struct bcom_gen_bd_tx_var {
        u32 fifo;               /* (u32*) address of gen_bd's fifo */
        u32 enable;             /* (u16*) address of task's control register */
        u32 bd_base;            /* (struct bcom_bd*) beginning of ring buffer */
        u32 bd_last;            /* (struct bcom_bd*) end of ring buffer */
        u32 bd_start;           /* (struct bcom_bd*) current bd */
        u32 buffer_size;        /* set by uCode for each packet */
};

/* tx task incs that need to be set before enabling the task */
struct bcom_gen_bd_tx_inc {
        u16 pad0;
        s16 incr_bytes;
        u16 pad1;
        s16 incr_src;
        u16 pad2;
        s16 incr_src_ma;
};

/* private structure */
struct bcom_gen_bd_priv {
        phys_addr_t     fifo;
        int             initiator;
        int             ipr;
        int             maxbufsize;
};


/* ======================================================================== */
/* Task support code                                                        */
/* ======================================================================== */

struct bcom_task *
bcom_gen_bd_rx_init(int queue_len, phys_addr_t fifo,
                        int initiator, int ipr, int maxbufsize)
{
        struct bcom_task *tsk;
        struct bcom_gen_bd_priv *priv;

        tsk = bcom_task_alloc(queue_len, sizeof(struct bcom_gen_bd),
                        sizeof(struct bcom_gen_bd_priv));
        if (!tsk)
                return NULL;

        tsk->flags = BCOM_FLAGS_NONE;

        priv = tsk->priv;
        priv->fifo      = fifo;
        priv->initiator = initiator;
        priv->ipr       = ipr;
        priv->maxbufsize = maxbufsize;

        if (bcom_gen_bd_rx_reset(tsk)) {
                bcom_task_free(tsk);
                return NULL;
        }

        return tsk;
}
EXPORT_SYMBOL_GPL(bcom_gen_bd_rx_init);

int
bcom_gen_bd_rx_reset(struct bcom_task *tsk)
{
        struct bcom_gen_bd_priv *priv = tsk->priv;
        struct bcom_gen_bd_rx_var *var;
        struct bcom_gen_bd_rx_inc *inc;

        /* Shutdown the task */
        bcom_disable_task(tsk->tasknum);

        /* Reset the microcode */
        var = (struct bcom_gen_bd_rx_var *) bcom_task_var(tsk->tasknum);
        inc = (struct bcom_gen_bd_rx_inc *) bcom_task_inc(tsk->tasknum);

        if (bcom_load_image(tsk->tasknum, bcom_gen_bd_rx_task))
                return -1;

        var->enable     = bcom_eng->regs_base +
                                offsetof(struct mpc52xx_sdma, tcr[tsk->tasknum]);
        var->fifo       = (u32) priv->fifo;
        var->bd_base    = tsk->bd_pa;
        var->bd_last    = tsk->bd_pa + ((tsk->num_bd-1) * tsk->bd_size);
        var->bd_start   = tsk->bd_pa;
        var->buffer_size = priv->maxbufsize;

        inc->incr_bytes = -(s16)sizeof(u32);
        inc->incr_dst   = sizeof(u32);

        /* Reset the BDs */
        tsk->index = 0;
        tsk->outdex = 0;

        memset_io(tsk->bd, 0x00, tsk->num_bd * tsk->bd_size);

        /* Configure some stuff */
        bcom_set_task_pragma(tsk->tasknum, BCOM_GEN_RX_BD_PRAGMA);
        bcom_set_task_auto_start(tsk->tasknum, tsk->tasknum);

        out_8(&bcom_eng->regs->ipr[priv->initiator], priv->ipr);
        bcom_set_initiator(tsk->tasknum, priv->initiator);

        out_be32(&bcom_eng->regs->IntPend, 1<<tsk->tasknum);    /* Clear ints */

        return 0;
}
EXPORT_SYMBOL_GPL(bcom_gen_bd_rx_reset);

void
bcom_gen_bd_rx_release(struct bcom_task *tsk)
{
        /* Nothing special for the GenBD tasks */
        bcom_task_free(tsk);
}
EXPORT_SYMBOL_GPL(bcom_gen_bd_rx_release);


extern struct bcom_task *
bcom_gen_bd_tx_init(int queue_len, phys_addr_t fifo,
                        int initiator, int ipr)
{
        struct bcom_task *tsk;
        struct bcom_gen_bd_priv *priv;

        tsk = bcom_task_alloc(queue_len, sizeof(struct bcom_gen_bd),
                        sizeof(struct bcom_gen_bd_priv));
        if (!tsk)
                return NULL;

        tsk->flags = BCOM_FLAGS_NONE;

        priv = tsk->priv;
        priv->fifo      = fifo;
        priv->initiator = initiator;
        priv->ipr       = ipr;

        if (bcom_gen_bd_tx_reset(tsk)) {
                bcom_task_free(tsk);
                return NULL;
        }

        return tsk;
}
EXPORT_SYMBOL_GPL(bcom_gen_bd_tx_init);

int
bcom_gen_bd_tx_reset(struct bcom_task *tsk)
{
        struct bcom_gen_bd_priv *priv = tsk->priv;
        struct bcom_gen_bd_tx_var *var;
        struct bcom_gen_bd_tx_inc *inc;

        /* Shutdown the task */
        bcom_disable_task(tsk->tasknum);

        /* Reset the microcode */
        var = (struct bcom_gen_bd_tx_var *) bcom_task_var(tsk->tasknum);
        inc = (struct bcom_gen_bd_tx_inc *) bcom_task_inc(tsk->tasknum);

        if (bcom_load_image(tsk->tasknum, bcom_gen_bd_tx_task))
                return -1;

        var->enable     = bcom_eng->regs_base +
                                offsetof(struct mpc52xx_sdma, tcr[tsk->tasknum]);
        var->fifo       = (u32) priv->fifo;
        var->bd_base    = tsk->bd_pa;
        var->bd_last    = tsk->bd_pa + ((tsk->num_bd-1) * tsk->bd_size);
        var->bd_start   = tsk->bd_pa;

        inc->incr_bytes = -(s16)sizeof(u32);
        inc->incr_src   = sizeof(u32);
        inc->incr_src_ma = sizeof(u8);

        /* Reset the BDs */
        tsk->index = 0;
        tsk->outdex = 0;

        memset_io(tsk->bd, 0x00, tsk->num_bd * tsk->bd_size);

        /* Configure some stuff */
        bcom_set_task_pragma(tsk->tasknum, BCOM_GEN_TX_BD_PRAGMA);
        bcom_set_task_auto_start(tsk->tasknum, tsk->tasknum);

        out_8(&bcom_eng->regs->ipr[priv->initiator], priv->ipr);
        bcom_set_initiator(tsk->tasknum, priv->initiator);

        out_be32(&bcom_eng->regs->IntPend, 1<<tsk->tasknum);    /* Clear ints */

        return 0;
}
EXPORT_SYMBOL_GPL(bcom_gen_bd_tx_reset);

void
bcom_gen_bd_tx_release(struct bcom_task *tsk)
{
        /* Nothing special for the GenBD tasks */
        bcom_task_free(tsk);
}
EXPORT_SYMBOL_GPL(bcom_gen_bd_tx_release);

/* ---------------------------------------------------------------------
 * PSC support code
 */

/**
 * bcom_psc_parameters - Bestcomm initialization value table for PSC devices
 *
 * This structure is only used internally.  It is a lookup table for PSC
 * specific parameters to bestcomm tasks.
 */
static struct bcom_psc_params {
        int rx_initiator;
        int rx_ipr;
        int tx_initiator;
        int tx_ipr;
} bcom_psc_params[] = {
        [0] = {
                .rx_initiator = BCOM_INITIATOR_PSC1_RX,
                .rx_ipr = BCOM_IPR_PSC1_RX,
                .tx_initiator = BCOM_INITIATOR_PSC1_TX,
                .tx_ipr = BCOM_IPR_PSC1_TX,
        },
        [1] = {
                .rx_initiator = BCOM_INITIATOR_PSC2_RX,
                .rx_ipr = BCOM_IPR_PSC2_RX,
                .tx_initiator = BCOM_INITIATOR_PSC2_TX,
                .tx_ipr = BCOM_IPR_PSC2_TX,
        },
        [2] = {
                .rx_initiator = BCOM_INITIATOR_PSC3_RX,
                .rx_ipr = BCOM_IPR_PSC3_RX,
                .tx_initiator = BCOM_INITIATOR_PSC3_TX,
                .tx_ipr = BCOM_IPR_PSC3_TX,
        },
        [3] = {
                .rx_initiator = BCOM_INITIATOR_PSC4_RX,
                .rx_ipr = BCOM_IPR_PSC4_RX,
                .tx_initiator = BCOM_INITIATOR_PSC4_TX,
                .tx_ipr = BCOM_IPR_PSC4_TX,
        },
        [4] = {
                .rx_initiator = BCOM_INITIATOR_PSC5_RX,
                .rx_ipr = BCOM_IPR_PSC5_RX,
                .tx_initiator = BCOM_INITIATOR_PSC5_TX,
                .tx_ipr = BCOM_IPR_PSC5_TX,
        },
        [5] = {
                .rx_initiator = BCOM_INITIATOR_PSC6_RX,
                .rx_ipr = BCOM_IPR_PSC6_RX,
                .tx_initiator = BCOM_INITIATOR_PSC6_TX,
                .tx_ipr = BCOM_IPR_PSC6_TX,
        },
};

/**
 * bcom_psc_gen_bd_rx_init - Allocate a receive bcom_task for a PSC port
 * @psc_num:    Number of the PSC to allocate a task for
 * @queue_len:  number of buffer descriptors to allocate for the task
 * @fifo:       physical address of FIFO register
 * @maxbufsize: Maximum receive data size in bytes.
 *
 * Allocate a bestcomm task structure for receiving data from a PSC.
 */
struct bcom_task * bcom_psc_gen_bd_rx_init(unsigned psc_num, int queue_len,
                                           phys_addr_t fifo, int maxbufsize)
{
        if (psc_num >= MPC52xx_PSC_MAXNUM)
                return NULL;

        return bcom_gen_bd_rx_init(queue_len, fifo,
                                   bcom_psc_params[psc_num].rx_initiator,
                                   bcom_psc_params[psc_num].rx_ipr,
                                   maxbufsize);
}
EXPORT_SYMBOL_GPL(bcom_psc_gen_bd_rx_init);

/**
 * bcom_psc_gen_bd_tx_init - Allocate a transmit bcom_task for a PSC port
 * @psc_num:    Number of the PSC to allocate a task for
 * @queue_len:  number of buffer descriptors to allocate for the task
 * @fifo:       physical address of FIFO register
 *
 * Allocate a bestcomm task structure for transmitting data to a PSC.
 */
struct bcom_task *
bcom_psc_gen_bd_tx_init(unsigned psc_num, int queue_len, phys_addr_t fifo)
{
        struct psc;
        return bcom_gen_bd_tx_init(queue_len, fifo,
                                   bcom_psc_params[psc_num].tx_initiator,
                                   bcom_psc_params[psc_num].tx_ipr);
}
EXPORT_SYMBOL_GPL(bcom_psc_gen_bd_tx_init);


MODULE_DESCRIPTION("BestComm General Buffer Descriptor tasks driver");
MODULE_AUTHOR("Jeff Gibbons <jeff.gibbons@appspec.com>");
MODULE_LICENSE("GPL v2");