ucc_slow.c

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/*
 * Copyright (C) 2006 Freescale Semicondutor, Inc. All rights reserved.
 *
 * Authors:     Shlomi Gridish <[email protected]>
 *      Li Yang <[email protected]>
 *
 * Description:
 * QE UCC Slow API Set - UCC Slow specific routines implementations.
 *
 * This program is free software; you can redistribute  it and/or modify it
 * under  the terms of  the GNU General  Public License as published by the
 * Free Software Foundation;  either version 2 of the  License, or (at your
 * option) any later version.
 */
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/stddef.h>
#include <linux/interrupt.h>
#include <linux/err.h>
#include <linux/export.h>

#include <asm/io.h>
#include <asm/immap_qe.h>
#include <asm/qe.h>

#include <asm/ucc.h>
#include <asm/ucc_slow.h>

u32 ucc_slow_get_qe_cr_subblock(int uccs_num)
{
    switch (uccs_num) {
    case 0: return QE_CR_SUBBLOCK_UCCSLOW1;
    case 1: return QE_CR_SUBBLOCK_UCCSLOW2;
    case 2: return QE_CR_SUBBLOCK_UCCSLOW3;
    case 3: return QE_CR_SUBBLOCK_UCCSLOW4;
    case 4: return QE_CR_SUBBLOCK_UCCSLOW5;
    case 5: return QE_CR_SUBBLOCK_UCCSLOW6;
    case 6: return QE_CR_SUBBLOCK_UCCSLOW7;
    case 7: return QE_CR_SUBBLOCK_UCCSLOW8;
    default: return QE_CR_SUBBLOCK_INVALID;
    }
}
EXPORT_SYMBOL(ucc_slow_get_qe_cr_subblock);

void ucc_slow_poll_transmitter_now(struct ucc_slow_private * uccs)
{
    out_be16(&uccs->us_regs->utodr, UCC_SLOW_TOD);
}

void ucc_slow_graceful_stop_tx(struct ucc_slow_private * uccs)
{
    struct ucc_slow_info *us_info = uccs->us_info;
    u32 id;

    id = ucc_slow_get_qe_cr_subblock(us_info->ucc_num);
    qe_issue_cmd(QE_GRACEFUL_STOP_TX, id,
             QE_CR_PROTOCOL_UNSPECIFIED, 0);
}
EXPORT_SYMBOL(ucc_slow_graceful_stop_tx);

void ucc_slow_stop_tx(struct ucc_slow_private * uccs)
{
    struct ucc_slow_info *us_info = uccs->us_info;
    u32 id;

    id = ucc_slow_get_qe_cr_subblock(us_info->ucc_num);
    qe_issue_cmd(QE_STOP_TX, id, QE_CR_PROTOCOL_UNSPECIFIED, 0);
}
EXPORT_SYMBOL(ucc_slow_stop_tx);

void ucc_slow_restart_tx(struct ucc_slow_private * uccs)
{
    struct ucc_slow_info *us_info = uccs->us_info;
    u32 id;

    id = ucc_slow_get_qe_cr_subblock(us_info->ucc_num);
    qe_issue_cmd(QE_RESTART_TX, id, QE_CR_PROTOCOL_UNSPECIFIED, 0);
}
EXPORT_SYMBOL(ucc_slow_restart_tx);

void ucc_slow_enable(struct ucc_slow_private * uccs, enum comm_dir mode)
{
    struct ucc_slow *us_regs;
    u32 gumr_l;

    us_regs = uccs->us_regs;

    /* Enable reception and/or transmission on this UCC. */
    gumr_l = in_be32(&us_regs->gumr_l);
    if (mode & COMM_DIR_TX) {
        gumr_l |= UCC_SLOW_GUMR_L_ENT;
        uccs->enabled_tx = 1;
    }
    if (mode & COMM_DIR_RX) {
        gumr_l |= UCC_SLOW_GUMR_L_ENR;
        uccs->enabled_rx = 1;
    }
    out_be32(&us_regs->gumr_l, gumr_l);
}
EXPORT_SYMBOL(ucc_slow_enable);

void ucc_slow_disable(struct ucc_slow_private * uccs, enum comm_dir mode)
{
    struct ucc_slow *us_regs;
    u32 gumr_l;

    us_regs = uccs->us_regs;

    /* Disable reception and/or transmission on this UCC. */
    gumr_l = in_be32(&us_regs->gumr_l);
    if (mode & COMM_DIR_TX) {
        gumr_l &= ~UCC_SLOW_GUMR_L_ENT;
        uccs->enabled_tx = 0;
    }
    if (mode & COMM_DIR_RX) {
        gumr_l &= ~UCC_SLOW_GUMR_L_ENR;
        uccs->enabled_rx = 0;
    }
    out_be32(&us_regs->gumr_l, gumr_l);
}
EXPORT_SYMBOL(ucc_slow_disable);

/* Initialize the UCC for Slow operations
 *
 * The caller should initialize the following us_info
 */
int ucc_slow_init(struct ucc_slow_info * us_info, struct ucc_slow_private ** uccs_ret)
{
    struct ucc_slow_private *uccs;
    u32 i;
    struct ucc_slow __iomem *us_regs;
    u32 gumr;
    struct qe_bd *bd;
    u32 id;
    u32 command;
    int ret = 0;

    if (!us_info)
        return -EINVAL;

    /* check if the UCC port number is in range. */
    if ((us_info->ucc_num < 0) || (us_info->ucc_num > UCC_MAX_NUM - 1)) {
        printk(KERN_ERR "%s: illegal UCC number\n", __func__);
        return -EINVAL;
    }

    /*
     * Set mrblr
     * Check that 'max_rx_buf_length' is properly aligned (4), unless
     * rfw is 1, meaning that QE accepts one byte at a time, unlike normal
     * case when QE accepts 32 bits at a time.
     */
    if ((!us_info->rfw) &&
        (us_info->max_rx_buf_length & (UCC_SLOW_MRBLR_ALIGNMENT - 1))) {
        printk(KERN_ERR "max_rx_buf_length not aligned.\n");
        return -EINVAL;
    }

    uccs = kzalloc(sizeof(struct ucc_slow_private), GFP_KERNEL);
    if (!uccs) {
        printk(KERN_ERR "%s: Cannot allocate private data\n",
            __func__);
        return -ENOMEM;
    }

    /* Fill slow UCC structure */
    uccs->us_info = us_info;
    /* Set the PHY base address */
    uccs->us_regs = ioremap(us_info->regs, sizeof(struct ucc_slow));
    if (uccs->us_regs == NULL) {
        printk(KERN_ERR "%s: Cannot map UCC registers\n", __func__);
        kfree(uccs);
        return -ENOMEM;
    }

    uccs->saved_uccm = 0;
    uccs->p_rx_frame = 0;
    us_regs = uccs->us_regs;
    uccs->p_ucce = (u16 *) & (us_regs->ucce);
    uccs->p_uccm = (u16 *) & (us_regs->uccm);
#ifdef STATISTICS
    uccs->rx_frames = 0;
    uccs->tx_frames = 0;
    uccs->rx_discarded = 0;
#endif              /* STATISTICS */

    /* Get PRAM base */
    uccs->us_pram_offset =
        qe_muram_alloc(UCC_SLOW_PRAM_SIZE, ALIGNMENT_OF_UCC_SLOW_PRAM);
    if (IS_ERR_VALUE(uccs->us_pram_offset)) {
        printk(KERN_ERR "%s: cannot allocate MURAM for PRAM", __func__);
        ucc_slow_free(uccs);
        return -ENOMEM;
    }
    id = ucc_slow_get_qe_cr_subblock(us_info->ucc_num);
    qe_issue_cmd(QE_ASSIGN_PAGE_TO_DEVICE, id, us_info->protocol,
             uccs->us_pram_offset);

    uccs->us_pram = qe_muram_addr(uccs->us_pram_offset);

    /* Set UCC to slow type */
    ret = ucc_set_type(us_info->ucc_num, UCC_SPEED_TYPE_SLOW);
    if (ret) {
        printk(KERN_ERR "%s: cannot set UCC type", __func__);
        ucc_slow_free(uccs);
        return ret;
    }

    out_be16(&uccs->us_pram->mrblr, us_info->max_rx_buf_length);

    INIT_LIST_HEAD(&uccs->confQ);

    /* Allocate BDs. */
    uccs->rx_base_offset =
        qe_muram_alloc(us_info->rx_bd_ring_len * sizeof(struct qe_bd),
                QE_ALIGNMENT_OF_BD);
    if (IS_ERR_VALUE(uccs->rx_base_offset)) {
        printk(KERN_ERR "%s: cannot allocate %u RX BDs\n", __func__,
            us_info->rx_bd_ring_len);
        uccs->rx_base_offset = 0;
        ucc_slow_free(uccs);
        return -ENOMEM;
    }

    uccs->tx_base_offset =
        qe_muram_alloc(us_info->tx_bd_ring_len * sizeof(struct qe_bd),
            QE_ALIGNMENT_OF_BD);
    if (IS_ERR_VALUE(uccs->tx_base_offset)) {
        printk(KERN_ERR "%s: cannot allocate TX BDs", __func__);
        uccs->tx_base_offset = 0;
        ucc_slow_free(uccs);
        return -ENOMEM;
    }

    /* Init Tx bds */
    bd = uccs->confBd = uccs->tx_bd = qe_muram_addr(uccs->tx_base_offset);
    for (i = 0; i < us_info->tx_bd_ring_len - 1; i++) {
        /* clear bd buffer */
        out_be32(&bd->buf, 0);
        /* set bd status and length */
        out_be32((u32 *) bd, 0);
        bd++;
    }
    /* for last BD set Wrap bit */
    out_be32(&bd->buf, 0);
    out_be32((u32 *) bd, cpu_to_be32(T_W));

    /* Init Rx bds */
    bd = uccs->rx_bd = qe_muram_addr(uccs->rx_base_offset);
    for (i = 0; i < us_info->rx_bd_ring_len - 1; i++) {
        /* set bd status and length */
        out_be32((u32*)bd, 0);
        /* clear bd buffer */
        out_be32(&bd->buf, 0);
        bd++;
    }
    /* for last BD set Wrap bit */
    out_be32((u32*)bd, cpu_to_be32(R_W));
    out_be32(&bd->buf, 0);

    /* Set GUMR (For more details see the hardware spec.). */
    /* gumr_h */
    gumr = us_info->tcrc;
    if (us_info->cdp)
        gumr |= UCC_SLOW_GUMR_H_CDP;
    if (us_info->ctsp)
        gumr |= UCC_SLOW_GUMR_H_CTSP;
    if (us_info->cds)
        gumr |= UCC_SLOW_GUMR_H_CDS;
    if (us_info->ctss)
        gumr |= UCC_SLOW_GUMR_H_CTSS;
    if (us_info->tfl)
        gumr |= UCC_SLOW_GUMR_H_TFL;
    if (us_info->rfw)
        gumr |= UCC_SLOW_GUMR_H_RFW;
    if (us_info->txsy)
        gumr |= UCC_SLOW_GUMR_H_TXSY;
    if (us_info->rtsm)
        gumr |= UCC_SLOW_GUMR_H_RTSM;
    out_be32(&us_regs->gumr_h, gumr);

    /* gumr_l */
    gumr = us_info->tdcr | us_info->rdcr | us_info->tenc | us_info->renc |
        us_info->diag | us_info->mode;
    if (us_info->tci)
        gumr |= UCC_SLOW_GUMR_L_TCI;
    if (us_info->rinv)
        gumr |= UCC_SLOW_GUMR_L_RINV;
    if (us_info->tinv)
        gumr |= UCC_SLOW_GUMR_L_TINV;
    if (us_info->tend)
        gumr |= UCC_SLOW_GUMR_L_TEND;
    out_be32(&us_regs->gumr_l, gumr);

    /* Function code registers */

    /* if the data is in cachable memory, the 'global' */
    /* in the function code should be set. */
    uccs->us_pram->tbmr = UCC_BMR_BO_BE;
    uccs->us_pram->rbmr = UCC_BMR_BO_BE;

    /* rbase, tbase are offsets from MURAM base */
    out_be16(&uccs->us_pram->rbase, uccs->rx_base_offset);
    out_be16(&uccs->us_pram->tbase, uccs->tx_base_offset);

    /* Mux clocking */
    /* Grant Support */
    ucc_set_qe_mux_grant(us_info->ucc_num, us_info->grant_support);
    /* Breakpoint Support */
    ucc_set_qe_mux_bkpt(us_info->ucc_num, us_info->brkpt_support);
    /* Set Tsa or NMSI mode. */
    ucc_set_qe_mux_tsa(us_info->ucc_num, us_info->tsa);
    /* If NMSI (not Tsa), set Tx and Rx clock. */
    if (!us_info->tsa) {
        /* Rx clock routing */
        if (ucc_set_qe_mux_rxtx(us_info->ucc_num, us_info->rx_clock,
                    COMM_DIR_RX)) {
            printk(KERN_ERR "%s: illegal value for RX clock\n",
                   __func__);
            ucc_slow_free(uccs);
            return -EINVAL;
        }
        /* Tx clock routing */
        if (ucc_set_qe_mux_rxtx(us_info->ucc_num, us_info->tx_clock,
                    COMM_DIR_TX)) {
            printk(KERN_ERR "%s: illegal value for TX clock\n",
                   __func__);
            ucc_slow_free(uccs);
            return -EINVAL;
        }
    }

    /* Set interrupt mask register at UCC level. */
    out_be16(&us_regs->uccm, us_info->uccm_mask);

    /* First, clear anything pending at UCC level,
     * otherwise, old garbage may come through
     * as soon as the dam is opened. */

    /* Writing '1' clears */
    out_be16(&us_regs->ucce, 0xffff);

    /* Issue QE Init command */
    if (us_info->init_tx && us_info->init_rx)
        command = QE_INIT_TX_RX;
    else if (us_info->init_tx)
        command = QE_INIT_TX;
    else
        command = QE_INIT_RX;   /* We know at least one is TRUE */

    qe_issue_cmd(command, id, us_info->protocol, 0);

    *uccs_ret = uccs;
    return 0;
}
EXPORT_SYMBOL(ucc_slow_init);

void ucc_slow_free(struct ucc_slow_private * uccs)
{
    if (!uccs)
        return;

    if (uccs->rx_base_offset)
        qe_muram_free(uccs->rx_base_offset);

    if (uccs->tx_base_offset)
        qe_muram_free(uccs->tx_base_offset);

    if (uccs->us_pram)
        qe_muram_free(uccs->us_pram_offset);

    if (uccs->us_regs)
        iounmap(uccs->us_regs);

    kfree(uccs);
}
EXPORT_SYMBOL(ucc_slow_free);