fhci-tds.c

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/*
 * Freescale QUICC Engine USB Host Controller Driver
 *
 * Copyright (c) Freescale Semicondutor, Inc. 2006.
 *               Shlomi Gridish <[email protected]>
 *               Jerry Huang <[email protected]>
 * Copyright (c) Logic Product Development, Inc. 2007
 *               Peter Barada <[email protected]>
 * Copyright (c) MontaVista Software, Inc. 2008.
 *               Anton Vorontsov <[email protected]>
 *
 * 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/types.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/io.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>
#include "fhci.h"

#define DUMMY_BD_BUFFER  0xdeadbeef
#define DUMMY2_BD_BUFFER 0xbaadf00d

/* Transaction Descriptors bits */
#define TD_R        0x8000 /* ready bit */
#define TD_W        0x2000 /* wrap bit */
#define TD_I        0x1000 /* interrupt on completion */
#define TD_L        0x0800 /* last */
#define TD_TC       0x0400 /* transmit CRC */
#define TD_CNF      0x0200 /* CNF - Must be always 1 */
#define TD_LSP      0x0100 /* Low-speed transaction */
#define TD_PID      0x00c0 /* packet id */
#define TD_RXER     0x0020 /* Rx error or not */

#define TD_NAK      0x0010 /* No ack. */
#define TD_STAL     0x0008 /* Stall received */
#define TD_TO       0x0004 /* time out */
#define TD_UN       0x0002 /* underrun */
#define TD_NO       0x0010 /* Rx Non Octet Aligned Packet */
#define TD_AB       0x0008 /* Frame Aborted */
#define TD_CR       0x0004 /* CRC Error */
#define TD_OV       0x0002 /* Overrun */
#define TD_BOV      0x0001 /* Buffer Overrun */

#define TD_ERRORS   (TD_NAK | TD_STAL | TD_TO | TD_UN | \
             TD_NO | TD_AB | TD_CR | TD_OV | TD_BOV)

#define TD_PID_DATA0    0x0080 /* Data 0 toggle */
#define TD_PID_DATA1    0x00c0 /* Data 1 toggle */
#define TD_PID_TOGGLE   0x00c0 /* Data 0/1 toggle mask */

#define TD_TOK_SETUP    0x0000
#define TD_TOK_OUT  0x4000
#define TD_TOK_IN   0x8000
#define TD_ISO      0x1000
#define TD_ENDP     0x0780
#define TD_ADDR     0x007f

#define TD_ENDP_SHIFT 7

struct usb_td {
    __be16 status;
    __be16 length;
    __be32 buf_ptr;
    __be16 extra;
    __be16 reserved;
};

static struct usb_td __iomem *next_bd(struct usb_td __iomem *base,
                      struct usb_td __iomem *td,
                      u16 status)
{
    if (status & TD_W)
        return base;
    else
        return ++td;
}

void fhci_push_dummy_bd(struct endpoint *ep)
{
    if (ep->already_pushed_dummy_bd == false) {
        u16 td_status = in_be16(&ep->empty_td->status);

        out_be32(&ep->empty_td->buf_ptr, DUMMY_BD_BUFFER);
        /* get the next TD in the ring */
        ep->empty_td = next_bd(ep->td_base, ep->empty_td, td_status);
        ep->already_pushed_dummy_bd = true;
    }
}

/* destroy an USB endpoint */
void fhci_ep0_free(struct fhci_usb *usb)
{
    struct endpoint *ep;
    int size;

    ep = usb->ep0;
    if (ep) {
        if (ep->td_base)
            cpm_muram_free(cpm_muram_offset(ep->td_base));

        if (kfifo_initialized(&ep->conf_frame_Q)) {
            size = cq_howmany(&ep->conf_frame_Q);
            for (; size; size--) {
                struct packet *pkt = cq_get(&ep->conf_frame_Q);

                kfree(pkt);
            }
            cq_delete(&ep->conf_frame_Q);
        }

        if (kfifo_initialized(&ep->empty_frame_Q)) {
            size = cq_howmany(&ep->empty_frame_Q);
            for (; size; size--) {
                struct packet *pkt = cq_get(&ep->empty_frame_Q);

                kfree(pkt);
            }
            cq_delete(&ep->empty_frame_Q);
        }

        if (kfifo_initialized(&ep->dummy_packets_Q)) {
            size = cq_howmany(&ep->dummy_packets_Q);
            for (; size; size--) {
                u8 *buff = cq_get(&ep->dummy_packets_Q);

                kfree(buff);
            }
            cq_delete(&ep->dummy_packets_Q);
        }

        kfree(ep);
        usb->ep0 = NULL;
    }
}

/*
 * create the endpoint structure
 *
 * arguments:
 * usb      A pointer to the data structure of the USB
 * data_mem The data memory partition(BUS)
 * ring_len TD ring length
 */
u32 fhci_create_ep(struct fhci_usb *usb, enum fhci_mem_alloc data_mem,
               u32 ring_len)
{
    struct endpoint *ep;
    struct usb_td __iomem *td;
    unsigned long ep_offset;
    char *err_for = "endpoint PRAM";
    int ep_mem_size;
    u32 i;

    /* we need at least 3 TDs in the ring */
    if (!(ring_len > 2)) {
        fhci_err(usb->fhci, "illegal TD ring length parameters\n");
        return -EINVAL;
    }

    ep = kzalloc(sizeof(*ep), GFP_KERNEL);
    if (!ep)
        return -ENOMEM;

    ep_mem_size = ring_len * sizeof(*td) + sizeof(struct fhci_ep_pram);
    ep_offset = cpm_muram_alloc(ep_mem_size, 32);
    if (IS_ERR_VALUE(ep_offset))
        goto err;
    ep->td_base = cpm_muram_addr(ep_offset);

    /* zero all queue pointers */
    if (cq_new(&ep->conf_frame_Q, ring_len + 2) ||
        cq_new(&ep->empty_frame_Q, ring_len + 2) ||
        cq_new(&ep->dummy_packets_Q, ring_len + 2)) {
        err_for = "frame_queues";
        goto err;
    }

    for (i = 0; i < (ring_len + 1); i++) {
        struct packet *pkt;
        u8 *buff;

        pkt = kmalloc(sizeof(*pkt), GFP_KERNEL);
        if (!pkt) {
            err_for = "frame";
            goto err;
        }

        buff = kmalloc(1028 * sizeof(*buff), GFP_KERNEL);
        if (!buff) {
            kfree(pkt);
            err_for = "buffer";
            goto err;
        }
        cq_put(&ep->empty_frame_Q, pkt);
        cq_put(&ep->dummy_packets_Q, buff);
    }

    /* we put the endpoint parameter RAM right behind the TD ring */
    ep->ep_pram_ptr = (void __iomem *)ep->td_base + sizeof(*td) * ring_len;

    ep->conf_td = ep->td_base;
    ep->empty_td = ep->td_base;

    ep->already_pushed_dummy_bd = false;

    /* initialize tds */
    td = ep->td_base;
    for (i = 0; i < ring_len; i++) {
        out_be32(&td->buf_ptr, 0);
        out_be16(&td->status, 0);
        out_be16(&td->length, 0);
        out_be16(&td->extra, 0);
        td++;
    }
    td--;
    out_be16(&td->status, TD_W); /* for last TD set Wrap bit */
    out_be16(&td->length, 0);

    /* endpoint structure has been created */
    usb->ep0 = ep;

    return 0;
err:
    fhci_ep0_free(usb);
    kfree(ep);
    fhci_err(usb->fhci, "no memory for the %s\n", err_for);
    return -ENOMEM;
}

/*
 * initialize the endpoint register according to the given parameters
 *
 * artuments:
 * usb      A pointer to the data strucutre of the USB
 * ep       A pointer to the endpoint structre
 * data_mem The data memory partition(BUS)
 */
void fhci_init_ep_registers(struct fhci_usb *usb, struct endpoint *ep,
                enum fhci_mem_alloc data_mem)
{
    u8 rt;

    /* set the endpoint registers according to the endpoint */
    out_be16(&usb->fhci->regs->usb_usep[0],
         USB_TRANS_CTR | USB_EP_MF | USB_EP_RTE);
    out_be16(&usb->fhci->pram->ep_ptr[0],
         cpm_muram_offset(ep->ep_pram_ptr));

    rt = (BUS_MODE_BO_BE | BUS_MODE_GBL);
#ifdef MULTI_DATA_BUS
    if (data_mem == MEM_SECONDARY)
        rt |= BUS_MODE_DTB;
#endif
    out_8(&ep->ep_pram_ptr->rx_func_code, rt);
    out_8(&ep->ep_pram_ptr->tx_func_code, rt);
    out_be16(&ep->ep_pram_ptr->rx_buff_len, 1028);
    out_be16(&ep->ep_pram_ptr->rx_base, 0);
    out_be16(&ep->ep_pram_ptr->tx_base, cpm_muram_offset(ep->td_base));
    out_be16(&ep->ep_pram_ptr->rx_bd_ptr, 0);
    out_be16(&ep->ep_pram_ptr->tx_bd_ptr, cpm_muram_offset(ep->td_base));
    out_be32(&ep->ep_pram_ptr->tx_state, 0);
}

/*
 * Collect the submitted frames and inform the application about them
 * It is also preparing the TDs for new frames. If the Tx interrupts
 * are disabled, the application should call that routine to get
 * confirmation about the submitted frames. Otherwise, the routine is
 * called from the interrupt service routine during the Tx interrupt.
 * In that case the application is informed by calling the application
 * specific 'fhci_transaction_confirm' routine
 */
static void fhci_td_transaction_confirm(struct fhci_usb *usb)
{
    struct endpoint *ep = usb->ep0;
    struct packet *pkt;
    struct usb_td __iomem *td;
    u16 extra_data;
    u16 td_status;
    u16 td_length;
    u32 buf;

    /*
     * collect transmitted BDs from the chip. The routine clears all BDs
     * with R bit = 0 and the pointer to data buffer is not NULL, that is
     * BDs which point to the transmitted data buffer
     */
    while (1) {
        td = ep->conf_td;
        td_status = in_be16(&td->status);
        td_length = in_be16(&td->length);
        buf = in_be32(&td->buf_ptr);
        extra_data = in_be16(&td->extra);

        /* check if the TD is empty */
        if (!(!(td_status & TD_R) && ((td_status & ~TD_W) || buf)))
            break;
        /* check if it is a dummy buffer */
        else if ((buf == DUMMY_BD_BUFFER) && !(td_status & ~TD_W))
            break;

        /* mark TD as empty */
        clrbits16(&td->status, ~TD_W);
        out_be16(&td->length, 0);
        out_be32(&td->buf_ptr, 0);
        out_be16(&td->extra, 0);
        /* advance the TD pointer */
        ep->conf_td = next_bd(ep->td_base, ep->conf_td, td_status);

        /* check if it is a dummy buffer(type2) */
        if ((buf == DUMMY2_BD_BUFFER) && !(td_status & ~TD_W))
            continue;

        pkt = cq_get(&ep->conf_frame_Q);
        if (!pkt)
            fhci_err(usb->fhci, "no frame to confirm\n");

        if (td_status & TD_ERRORS) {
            if (td_status & TD_RXER) {
                if (td_status & TD_CR)
                    pkt->status = USB_TD_RX_ER_CRC;
                else if (td_status & TD_AB)
                    pkt->status = USB_TD_RX_ER_BITSTUFF;
                else if (td_status & TD_OV)
                    pkt->status = USB_TD_RX_ER_OVERUN;
                else if (td_status & TD_BOV)
                    pkt->status = USB_TD_RX_DATA_OVERUN;
                else if (td_status & TD_NO)
                    pkt->status = USB_TD_RX_ER_NONOCT;
                else
                    fhci_err(usb->fhci, "illegal error "
                         "occurred\n");
            } else if (td_status & TD_NAK)
                pkt->status = USB_TD_TX_ER_NAK;
            else if (td_status & TD_TO)
                pkt->status = USB_TD_TX_ER_TIMEOUT;
            else if (td_status & TD_UN)
                pkt->status = USB_TD_TX_ER_UNDERUN;
            else if (td_status & TD_STAL)
                pkt->status = USB_TD_TX_ER_STALL;
            else
                fhci_err(usb->fhci, "illegal error occurred\n");
        } else if ((extra_data & TD_TOK_IN) &&
                pkt->len > td_length - CRC_SIZE) {
            pkt->status = USB_TD_RX_DATA_UNDERUN;
        }

        if (extra_data & TD_TOK_IN)
            pkt->len = td_length - CRC_SIZE;
        else if (pkt->info & PKT_ZLP)
            pkt->len = 0;
        else
            pkt->len = td_length;

        fhci_transaction_confirm(usb, pkt);
    }
}

/*
 * Submitting a data frame to a specified endpoint of a USB device
 * The frame is put in the driver's transmit queue for this endpoint
 *
 * Arguments:
 * usb          A pointer to the USB structure
 * pkt          A pointer to the user frame structure
 * trans_type   Transaction tyep - IN,OUT or SETUP
 * dest_addr    Device address - 0~127
 * dest_ep      Endpoint number of the device - 0~16
 * trans_mode   Pipe type - ISO,Interrupt,bulk or control
 * dest_speed   USB speed - Low speed or FULL speed
 * data_toggle  Data sequence toggle - 0 or 1
 */
u32 fhci_host_transaction(struct fhci_usb *usb,
              struct packet *pkt,
              enum fhci_ta_type trans_type,
              u8 dest_addr,
              u8 dest_ep,
              enum fhci_tf_mode trans_mode,
              enum fhci_speed dest_speed, u8 data_toggle)
{
    struct endpoint *ep = usb->ep0;
    struct usb_td __iomem *td;
    u16 extra_data;
    u16 td_status;

    fhci_usb_disable_interrupt(usb);
    /* start from the next BD that should be filled */
    td = ep->empty_td;
    td_status = in_be16(&td->status);

    if (td_status & TD_R && in_be16(&td->length)) {
        /* if the TD is not free */
        fhci_usb_enable_interrupt(usb);
        return -1;
    }

    /* get the next TD in the ring */
    ep->empty_td = next_bd(ep->td_base, ep->empty_td, td_status);
    fhci_usb_enable_interrupt(usb);
    pkt->priv_data = td;
    out_be32(&td->buf_ptr, virt_to_phys(pkt->data));
    /* sets up transaction parameters - addr,endp,dir,and type */
    extra_data = (dest_ep << TD_ENDP_SHIFT) | dest_addr;
    switch (trans_type) {
    case FHCI_TA_IN:
        extra_data |= TD_TOK_IN;
        break;
    case FHCI_TA_OUT:
        extra_data |= TD_TOK_OUT;
        break;
    case FHCI_TA_SETUP:
        extra_data |= TD_TOK_SETUP;
        break;
    }
    if (trans_mode == FHCI_TF_ISO)
        extra_data |= TD_ISO;
    out_be16(&td->extra, extra_data);

    /* sets up the buffer descriptor */
    td_status = ((td_status & TD_W) | TD_R | TD_L | TD_I | TD_CNF);
    if (!(pkt->info & PKT_NO_CRC))
        td_status |= TD_TC;

    switch (trans_type) {
    case FHCI_TA_IN:
        if (data_toggle)
            pkt->info |= PKT_PID_DATA1;
        else
            pkt->info |= PKT_PID_DATA0;
        break;
    default:
        if (data_toggle) {
            td_status |= TD_PID_DATA1;
            pkt->info |= PKT_PID_DATA1;
        } else {
            td_status |= TD_PID_DATA0;
            pkt->info |= PKT_PID_DATA0;
        }
        break;
    }

    if ((dest_speed == FHCI_LOW_SPEED) &&
        (usb->port_status == FHCI_PORT_FULL))
        td_status |= TD_LSP;

    out_be16(&td->status, td_status);

    /* set up buffer length */
    if (trans_type == FHCI_TA_IN)
        out_be16(&td->length, pkt->len + CRC_SIZE);
    else
        out_be16(&td->length, pkt->len);

    /* put the frame to the confirmation queue */
    cq_put(&ep->conf_frame_Q, pkt);

    if (cq_howmany(&ep->conf_frame_Q) == 1)
        out_8(&usb->fhci->regs->usb_uscom, USB_CMD_STR_FIFO);

    return 0;
}

/* Reset the Tx BD ring */
void fhci_flush_bds(struct fhci_usb *usb)
{
    u16 extra_data;
    u16 td_status;
    u32 buf;
    struct usb_td __iomem *td;
    struct endpoint *ep = usb->ep0;

    td = ep->td_base;
    while (1) {
        td_status = in_be16(&td->status);
        buf = in_be32(&td->buf_ptr);
        extra_data = in_be16(&td->extra);

        /* if the TD is not empty - we'll confirm it as Timeout */
        if (td_status & TD_R)
            out_be16(&td->status, (td_status & ~TD_R) | TD_TO);
        /* if this TD is dummy - let's skip this TD */
        else if (in_be32(&td->buf_ptr) == DUMMY_BD_BUFFER)
            out_be32(&td->buf_ptr, DUMMY2_BD_BUFFER);
        /* if this is the last TD - break */
        if (td_status & TD_W)
            break;

        td++;
    }

    fhci_td_transaction_confirm(usb);

    td = ep->td_base;
    do {
        out_be16(&td->status, 0);
        out_be16(&td->length, 0);
        out_be32(&td->buf_ptr, 0);
        out_be16(&td->extra, 0);
        td++;
    } while (!(in_be16(&td->status) & TD_W));
    out_be16(&td->status, TD_W); /* for last TD set Wrap bit */
    out_be16(&td->length, 0);
    out_be32(&td->buf_ptr, 0);
    out_be16(&td->extra, 0);

    out_be16(&ep->ep_pram_ptr->tx_bd_ptr,
         in_be16(&ep->ep_pram_ptr->tx_base));
    out_be32(&ep->ep_pram_ptr->tx_state, 0);
    out_be16(&ep->ep_pram_ptr->tx_cnt, 0);
    ep->empty_td = ep->td_base;
    ep->conf_td = ep->td_base;
}

/*
 * Flush all transmitted packets from TDs in the actual frame.
 * This routine is called when something wrong with the controller and
 * we want to get rid of the actual frame and start again next frame
 */
void fhci_flush_actual_frame(struct fhci_usb *usb)
{
    u8 mode;
    u16 tb_ptr;
    u16 extra_data;
    u16 td_status;
    u32 buf_ptr;
    struct usb_td __iomem *td;
    struct endpoint *ep = usb->ep0;

    /* disable the USB controller */
    mode = in_8(&usb->fhci->regs->usb_usmod);
    out_8(&usb->fhci->regs->usb_usmod, mode & ~USB_MODE_EN);

    tb_ptr = in_be16(&ep->ep_pram_ptr->tx_bd_ptr);
    td = cpm_muram_addr(tb_ptr);
    td_status = in_be16(&td->status);
    buf_ptr = in_be32(&td->buf_ptr);
    extra_data = in_be16(&td->extra);
    do {
        if (td_status & TD_R) {
            out_be16(&td->status, (td_status & ~TD_R) | TD_TO);
        } else {
            out_be32(&td->buf_ptr, 0);
            ep->already_pushed_dummy_bd = false;
            break;
        }

        /* advance the TD pointer */
        td = next_bd(ep->td_base, td, td_status);
        td_status = in_be16(&td->status);
        buf_ptr = in_be32(&td->buf_ptr);
        extra_data = in_be16(&td->extra);
    } while ((td_status & TD_R) || buf_ptr);

    fhci_td_transaction_confirm(usb);

    out_be16(&ep->ep_pram_ptr->tx_bd_ptr,
         in_be16(&ep->ep_pram_ptr->tx_base));
    out_be32(&ep->ep_pram_ptr->tx_state, 0);
    out_be16(&ep->ep_pram_ptr->tx_cnt, 0);
    ep->empty_td = ep->td_base;
    ep->conf_td = ep->td_base;

    usb->actual_frame->frame_status = FRAME_TIMER_END_TRANSMISSION;

    /* reset the event register */
    out_be16(&usb->fhci->regs->usb_usber, 0xffff);
    /* enable the USB controller */
    out_8(&usb->fhci->regs->usb_usmod, mode | USB_MODE_EN);
}

/* handles Tx confirm and Tx error interrupt */
void fhci_tx_conf_interrupt(struct fhci_usb *usb)
{
    fhci_td_transaction_confirm(usb);

    /*
     * Schedule another transaction to this frame only if we have
     * already confirmed all transaction in the frame.
     */
    if (((fhci_get_sof_timer_count(usb) < usb->max_frame_usage) ||
         (usb->actual_frame->frame_status & FRAME_END_TRANSMISSION)) &&
        (list_empty(&usb->actual_frame->tds_list)))
        fhci_schedule_transactions(usb);
}

void fhci_host_transmit_actual_frame(struct fhci_usb *usb)
{
    u16 tb_ptr;
    u16 td_status;
    struct usb_td __iomem *td;
    struct endpoint *ep = usb->ep0;

    tb_ptr = in_be16(&ep->ep_pram_ptr->tx_bd_ptr);
    td = cpm_muram_addr(tb_ptr);

    if (in_be32(&td->buf_ptr) == DUMMY_BD_BUFFER) {
        struct usb_td __iomem *old_td = td;

        ep->already_pushed_dummy_bd = false;
        td_status = in_be16(&td->status);
        /* gets the next TD in the ring */
        td = next_bd(ep->td_base, td, td_status);
        tb_ptr = cpm_muram_offset(td);
        out_be16(&ep->ep_pram_ptr->tx_bd_ptr, tb_ptr);

        /* start transmit only if we have something in the TDs */
        if (in_be16(&td->status) & TD_R)
            out_8(&usb->fhci->regs->usb_uscom, USB_CMD_STR_FIFO);

        if (in_be32(&ep->conf_td->buf_ptr) == DUMMY_BD_BUFFER) {
            out_be32(&old_td->buf_ptr, 0);
            ep->conf_td = next_bd(ep->td_base, ep->conf_td,
                          td_status);
        } else {
            out_be32(&old_td->buf_ptr, DUMMY2_BD_BUFFER);
        }
    }
}