uboot-vybrid_public/drivers/usbdcore_mpc8xx.c

/*
 * Copyright (C) 2006 by Bryan O'Donoghue, CodeHermit
 * bodonoghue@CodeHermit.ie                                             
 *
 * References
 * DasUBoot/drivers/usbdcore_omap1510.c, for design and implementation ideas.
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the
 * Free Software Foundation, Inc.,
 * 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 */

/*
 * Notes :
 * 1.	#define __SIMULATE_ERROR__ to inject a CRC error into every 2nd TX 
 *		packet to force the USB re-transmit protocol.
 *
 * 2.	#define __DEBUG_UDC__ to switch on debug tracing to serial console
 * 	be careful that tracing doesn't create Hiesen-bugs with respect to
 * 	response timeouts to control requests.
 *
 * 3.	This driver should be able to support any higher level driver that
 *	that wants to do either of the two standard UDC implementations
 *	Control-Bulk-Interrupt or  Bulk-IN/Bulk-Out standards. Hence
 *	gserial and cdc_acm should work with this code.
 *
 * 4.	NAK events never actually get raised at all, the documentation
 *	is just wrong !
 *
 * 5.	For some reason, cbd_datlen is *always* +2 the value it should be.
 *	this means that having an RX cbd of 16 bytes is not possible, since
 * 	the same size is reported for 14 bytes received as 16 bytes received
 *	until we can find out why this happens, RX cbds must be limited to 8
 *	bytes. TODO: check errata for this behaviour.
 *
 * 6.	Right now this code doesn't support properly powering up with the USB
 * 	cable attached to the USB host my development board the Adder87x doesn't
 * 	have a pull-up fitted to allow this, so it is necessary to power the
 * 	board and *then* attached the USB cable to the host. However somebody
 * 	with a different design in their board may be able to keep the cable
 * 	constantly connected and simply enable/disable a pull-up  re
 * 	figure 31.1 in MPC885RM.pdf instead of having to power up the board and
 * 	then attach the cable !
 *
 */
#include <common.h>
#include <config.h>

#if defined(CONFIG_MPC885_FAMILY) && defined(CONFIG_USB_DEVICE)
#include <commproc.h>
#include "usbdcore.h"	
#include "usbdcore_mpc8xx.h"
#include "usbdcore_ep0.h"

#define ERR(fmt, args...)\
	serial_printf("ERROR : [%s] %s:%d: "fmt,\
				__FILE__,__FUNCTION__,__LINE__, ##args)
#ifdef __DEBUG_UDC__
	#define DBG(fmt,args...)\
		serial_printf("[%s] %s:%d: "fmt,\
				__FILE__,__FUNCTION__,__LINE__, ##args)
#else
	#define DBG(fmt,args...)
#endif

/* Static Data */
#ifdef __SIMULATE_ERROR__
	static char err_poison_test = 0;
#endif
static struct mpc8xx_ep ep_ref[MAX_ENDPOINTS];
static u32 address_base = STATE_NOT_READY;
static mpc8xx_udc_state_t udc_state = 0;
static struct usb_device_instance *udc_device = 0;
static volatile usb_epb_t *endpoints[MAX_ENDPOINTS];		
static volatile cbd_t * tx_cbd[TX_RING_SIZE];
static volatile cbd_t * rx_cbd[RX_RING_SIZE];
static volatile immap_t *immr = 0;
static volatile cpm8xx_t *cp = 0;
static volatile usb_pram_t *usb_paramp = 0;
static volatile usb_t *usbp = 0;
static int rx_ct = 0;
static int tx_ct = 0;

/* Static Function Declarations */
static void mpc8xx_udc_state_transition_up (usb_device_state_t initial,
                                            usb_device_state_t final);    
static void mpc8xx_udc_state_transition_down (usb_device_state_t initial,
                                              usb_device_state_t final);
static void mpc8xx_udc_stall (unsigned int ep);
static void mpc8xx_udc_flush_tx_fifo(int epid);
static void mpc8xx_udc_flush_rx_fifo(void);
static void mpc8xx_udc_clear_rxbd (volatile cbd_t * rx_cbdp);
static void mpc8xx_udc_init_tx(struct usb_endpoint_instance *epi, 
		struct urb * tx_urb);
static void mpc8xx_udc_dump_request(struct usb_device_request *request);
static void mpc8xx_udc_clock_init (volatile immap_t * immr, 
		volatile cpm8xx_t * cp);
static int mpc8xx_udc_ep_tx (struct usb_endpoint_instance *epi);
static int mpc8xx_udc_epn_rx (unsigned int epid, volatile cbd_t * rx_cbdp);
static void mpc8xx_udc_ep0_rx(volatile cbd_t * rx_cbdp);
static void mpc8xx_udc_cbd_init (void);
static void mpc8xx_udc_endpoint_init (void);
static void mpc8xx_udc_cbd_attach (int ep, uchar tx_size, uchar rx_size);
static u32 mpc8xx_udc_alloc (u32 data_size, u32 alignment);
static int mpc8xx_udc_ep0_rx_setup (volatile cbd_t * rx_cbdp);
static void mpc8xx_udc_set_nak (unsigned int ep);
static short mpc8xx_udc_handle_txerr(void);
static void mpc8xx_udc_advance_rx(volatile cbd_t ** rx_cbdp, int epid);

/******************************************************************************
                               Global Linkage
 *****************************************************************************/

/* udc_init
 *
 * Do initial bus gluing
 */
int udc_init(void)
{
	/* Init various pointers */
	immr = (immap_t *) CFG_IMMR;
	cp = (cpm8xx_t *)&(immr->im_cpm);
	usb_paramp = (usb_pram_t*)&(cp->cp_dparam[PROFF_USB]);
	usbp = (usb_t *) &(cp->cp_scc[0]);

	memset(ep_ref, 0x00, (sizeof(struct mpc8xx_ep) * MAX_ENDPOINTS));
	
	udc_device = 0;
	udc_state = STATE_NOT_READY;
	
	usbp->usmod= 0x00;
	usbp->uscom= 0;
		
	/* Set USB Frame #0, Respond at Address & Get a clock source  */
	usbp->usaddr = 0x00;
	mpc8xx_udc_clock_init (immr, cp);
	
	/* PA15, PA14 as perhiperal USBRXD and USBOE */
	immr->im_ioport.iop_padir&= ~0x0003;
	immr->im_ioport.iop_papar|= 0x0003;
				
	/* PC11/PC10 as peripheral USBRXP USBRXN */
	immr->im_ioport.iop_pcso|= 0x0030;
	
	/* PC7/PC6 as perhiperal USBTXP and USBTXN */
	immr->im_ioport.iop_pcdir|= 0x0300;
	immr->im_ioport.iop_pcpar|= 0x0300;
	
	/* Set the base address */
	address_base = (u32)(cp->cp_dpmem + CPM_USB_BASE);

	/* Initialise endpoints and circular buffers */
	mpc8xx_udc_endpoint_init();	
	mpc8xx_udc_cbd_init();		
		
	/* Assign allocated Dual Port Endpoint descriptors */
	usb_paramp->ep0ptr = (u32)endpoints[0];
	usb_paramp->ep1ptr = (u32)endpoints[1];
	usb_paramp->ep2ptr = (u32)endpoints[2];
	usb_paramp->ep3ptr = (u32)endpoints[3];
	usb_paramp->frame_n = 0;

	DBG("ep0ptr=0x%08x ep1ptr=0x%08x ep2ptr=0x%08x ep3ptr=0x%08x\n",
		usb_paramp->ep0ptr, usb_paramp->ep1ptr, usb_paramp->ep2ptr,
		usb_paramp->ep3ptr);
	
	return 0;
}

/* udc_irq
 *
 * Poll for whatever events may have occured
 */
void udc_irq(void)
{
	int epid = 0;
	volatile cbd_t * rx_cbdp = 0;
	volatile cbd_t * rx_cbdp_base = 0;

	if(udc_state!=STATE_READY){
		return;
	}
	
	if(usbp->usber&USB_E_BSY){
		/* This shouldn't happen. If it does then it's a bug ! */
		usbp->usber|=USB_E_BSY;	
		mpc8xx_udc_flush_rx_fifo();
	}

	
	/* Scan all RX/Bidirectional Endpoints for RX data. */
	for(epid = 0; epid<MAX_ENDPOINTS; epid++){
				
		if(!ep_ref[epid].prx){
			continue;
		}

		rx_cbdp = rx_cbdp_base = ep_ref[epid].prx;
		do{
			if(!(rx_cbdp->cbd_sc&RX_BD_E)){
				
				if(rx_cbdp->cbd_sc&0x1F){
					/* Corrupt data discard it.
					 * Controller has NAK'd this packet. 
					 */
					mpc8xx_udc_clear_rxbd(rx_cbdp);

				}else{
					if(!epid){
						mpc8xx_udc_ep0_rx(rx_cbdp);

					}else{
						/* Process data */
						mpc8xx_udc_set_nak(epid);
						mpc8xx_udc_epn_rx(epid,rx_cbdp);
						mpc8xx_udc_clear_rxbd(rx_cbdp);
					}	
				}
				
				/* Advance RX CBD pointer */
				mpc8xx_udc_advance_rx(&rx_cbdp, epid);
				ep_ref[epid].prx = rx_cbdp;
			}else{
				/* Advance RX CBD pointer */
				mpc8xx_udc_advance_rx(&rx_cbdp, epid);
			}

		}while(rx_cbdp != rx_cbdp_base);
	}

	/* Handle TX events as appropiate, the correct place to do this is
	 * in a tx routine. Perhaps TX on epn was pre-empted by ep0
	 */

	if(usbp->usber&USB_E_TXB){
		usbp->usber|=USB_E_TXB;
	}
	
	if(usbp->usber&(USB_TX_ERRMASK)){
		mpc8xx_udc_handle_txerr();
	}

	/* Switch to the default state, respond at the default address */
	if(usbp->usber&USB_E_RESET){
		usbp->usber|=USB_E_RESET;
		usbp->usaddr = 0x00;	
		udc_device->device_state = STATE_DEFAULT;
	}

	/*if(usbp->usber&USB_E_IDLE){
		We could suspend here !
		usbp->usber|=USB_E_IDLE;
		DBG("idle state change\n");		
	}			
	if(usbp->usbs){
		We could resume here when IDLE is deasserted !
		Not worth doing, so long as we are self powered though.
	}*/

	return;
}



/* udc_endpoint_write
 *
 * Write some data to an endpoint
 */
int udc_endpoint_write(struct usb_endpoint_instance *epi)
{
	int ep = 0;
	short epid = 1, unnak = 0, ret = 0;

	if(udc_state != STATE_READY){
		ERR("invalid udc_state != STATE_READY!\n");
		return -1;
	}

	if(!udc_device || !epi){
		return -1;
	}
	
	if(udc_device->device_state!=STATE_CONFIGURED){
		return -1;
	}

	ep = epi->endpoint_address & 0x03;
	if(ep >= MAX_ENDPOINTS){
		return -1;
	}
	
	/* Set NAK for all RX endpoints during TX */
	for(epid = 1; epid<MAX_ENDPOINTS; epid++){

		/* Don't set NAK on DATA IN/CONTROL endpoints */
		if(ep_ref[epid].sc & USB_DIR_IN){
			continue;
		}

		if(!(usbp->usep[epid]&( USEP_THS_NAK | USEP_RHS_NAK ))){
			unnak |= 1<<epid;
		}

		mpc8xx_udc_set_nak(epid);
	}

	mpc8xx_udc_init_tx(&udc_device->bus->endpoint_array[ep],epi->tx_urb);
	ret = mpc8xx_udc_ep_tx(&udc_device->bus->endpoint_array[ep]);
	
	/* Remove temporary NAK */
	for(epid = 1; epid<MAX_ENDPOINTS; epid++){
		if(unnak&(1<<epid)){
			udc_unset_nak(epid);
		}
	}
	
	return ret;
}

/* mpc8xx_udc_assign_urb
 *
 * Associate a given urb to an endpoint TX or RX transmit/receive buffers
 */
static int mpc8xx_udc_assign_urb(int ep, char direction)
{
	struct usb_endpoint_instance *epi = 0;
	
	if(ep >= MAX_ENDPOINTS){
		goto err;
	}
	epi = &udc_device->bus->endpoint_array[ep];
	if(!epi){
		goto err;
	}

	if(!ep_ref[ep].urb){
		ep_ref[ep].urb = usbd_alloc_urb(udc_device, 
			udc_device->bus->endpoint_array);
		if(!ep_ref[ep].urb){
			goto err;
		}
	}else{
		ep_ref[ep].urb->actual_length = 0;
	}

	switch(direction){
		case USB_DIR_IN:
			epi->tx_urb = ep_ref[ep].urb;
			break;
		case USB_DIR_OUT:
			epi->rcv_urb = ep_ref[ep].urb;
			break;
		default:
			goto err;
	}
	return 0;

err:
	udc_state = STATE_ERROR;
	return -1;
}

/* udc_setup_ep
 *
 * Associate U-Boot software endpoints to mpc8xx endpoint parameter ram
 * Isochronous endpoints aren't yet supported!
 */
void udc_setup_ep(struct usb_device_instance *device, unsigned int ep,
                  struct usb_endpoint_instance *epi)
{
	uchar direction = 0;
	int ep_attrib = 0;

	if(epi && (ep < MAX_ENDPOINTS)){
		
		if(ep == 0){
			if (epi->rcv_attributes!=USB_ENDPOINT_XFER_CONTROL 
				||epi->tx_attributes!= 
				USB_ENDPOINT_XFER_CONTROL){

				/* ep0 must be a control endpoint*/
				udc_state = STATE_ERROR;
				return;

			}
			if(!(ep_ref[ep].sc & EP_ATTACHED)){
				mpc8xx_udc_cbd_attach (ep, epi->tx_packetSize, 
					epi->rcv_packetSize);
			}
			usbp->usep[ep] = 0x0000;
			return;
		}
		
		if ((epi->endpoint_address & USB_ENDPOINT_DIR_MASK) 
			== USB_DIR_IN) {

			direction = 1;
			ep_attrib = epi->tx_attributes;
			epi->rcv_packetSize = 0;
			ep_ref[ep].sc |= USB_DIR_IN;		
		} else {
			
			direction = 0;
			ep_attrib = epi->rcv_attributes;
			epi->tx_packetSize = 0;	
			ep_ref[ep].sc &= ~USB_DIR_IN;
		}

		if(mpc8xx_udc_assign_urb(ep, epi->endpoint_address
					&USB_ENDPOINT_DIR_MASK)){
			return;
		}

		switch(ep_attrib){
			case USB_ENDPOINT_XFER_CONTROL:
				if(!(ep_ref[ep].sc & EP_ATTACHED)){
					mpc8xx_udc_cbd_attach (ep,
						epi->tx_packetSize, 
						epi->rcv_packetSize);
				}
				usbp->usep[ep] = ep<<12;
				epi->rcv_urb = epi->tx_urb = ep_ref[ep].urb;

				break;
			case USB_ENDPOINT_XFER_BULK :
			case USB_ENDPOINT_XFER_INT:
				if(!(ep_ref[ep].sc & EP_ATTACHED)){
					if(direction){
						mpc8xx_udc_cbd_attach (ep, 
							epi->tx_packetSize, 0);
					}else{
						mpc8xx_udc_cbd_attach (ep, 
							0, epi->rcv_packetSize);
					}
				}
				usbp->usep[ep]=	(ep<<12)|((ep_attrib)<<8);
					
				break;
			case USB_ENDPOINT_XFER_ISOC:
			default:
				serial_printf("Error endpoint attrib %d>3\n",
						ep_attrib);
				udc_state = STATE_ERROR;
				break;
		}
	}

}

/* udc_connect
 *
 * Move state, switch on the USB
 */
void udc_connect(void)
{
	/* Enable pull-up resistor on D+ 
	 * TODO: fit a pull-up resistor to drive SE0 for > 2.5us
	 */
	
	if(udc_state!=STATE_ERROR){
		udc_state = STATE_READY;
		usbp->usmod|= USMOD_EN;
	}
}	

/* udc_disconnect
 *
 * Disconnect is not used but, is included for completeness
 */
void udc_disconnect(void)
{
	/* Disable pull-up resistor on D-
	 * TODO: fix a pullup resistor to control this
	 */

	if(udc_state!=STATE_ERROR){
		udc_state = STATE_NOT_READY;
	}
	usbp->usmod&=~USMOD_EN;
}

/* udc_enable
 * 
 * Grab an EP0 URB, register interest in a subset of USB events
 */
void udc_enable(struct usb_device_instance *device)
{
	if(udc_state == STATE_ERROR){
		return;
	}

	udc_device = device;
	
	if(!ep_ref[0].urb){
		ep_ref[0].urb = usbd_alloc_urb(device, 
					device->bus->endpoint_array);
	}

	/* Register interest in all events except SOF, enable transceiver */
	usbp->usber= 0x03FF;
	usbp->usbmr= 0x02F7;

	return;
}

/* udc_disable
 *
 * disable the currently hooked device
 */
void udc_disable(void)
{
	int i = 0;

	if(udc_state == STATE_ERROR){
		DBG("Won't disable UDC. udc_state==STATE_ERROR !\n");
		return;
	}

	udc_device = 0;

	for(;i<MAX_ENDPOINTS; i++){
		if(ep_ref[i].urb){
			usbd_dealloc_urb(ep_ref[i].urb);
			ep_ref[i].urb = 0;
		}
	}
		
	usbp->usbmr= 0x00;	
	usbp->usmod= ~USMOD_EN;
	udc_state = STATE_NOT_READY;
}

/* udc_startup_events
 *
 * Enable the specified device
 */
void udc_startup_events(struct usb_device_instance *device)
{
	udc_enable(device);
	if(udc_state == STATE_READY){
		usbd_device_event_irq (device, DEVICE_CREATE, 0);
	}
}

/* udc_set_nak
 * 
 * Allow upper layers to signal lower layers should not accept more RX data
 *
 */
void udc_set_nak(int epid)
{
	if(epid){
		mpc8xx_udc_set_nak(epid);
	}
}

/* udc_unset_nak 
 * 
 * Suspend sending of NAK tokens for DATA OUT tokens on a given endpoint.
 * Switch off NAKing on this endpoint to accept more data output from host.
 *
 */
void udc_unset_nak (int epid)
{
	if(epid > MAX_ENDPOINTS){
		return;
	}

	if(usbp->usep[epid]&(USEP_THS_NAK | USEP_RHS_NAK)){
		usbp->usep[epid]&= ~(USEP_THS_NAK | USEP_RHS_NAK);
		__asm__ ("eieio");
	}
}

/******************************************************************************
                              Static Linkage
******************************************************************************/

/* udc_state_transition_up
 * udc_state_transition_down
 *
 * Helper functions to implement device state changes.	The device states and
 * the events that transition between them are:
 *
 *				STATE_ATTACHED
 *				||	/\
 *				\/	||
 *	DEVICE_HUB_CONFIGURED			DEVICE_HUB_RESET
 *				||	/\
 *				\/	||
 *				STATE_POWERED
 *				||	/\
 *				\/	||
 *	DEVICE_RESET				DEVICE_POWER_INTERRUPTION
 *				||	/\
 *				\/	||
 *				STATE_DEFAULT
 *				||	/\
 *				\/	||
 *	DEVICE_ADDRESS_ASSIGNED			DEVICE_RESET
 *				||	/\
 *				\/	||
 *				STATE_ADDRESSED
 *				||	/\
 *				\/	||
 *	DEVICE_CONFIGURED			DEVICE_DE_CONFIGURED
 *				||	/\
 *				\/	||
 *				STATE_CONFIGURED
 *
 * udc_state_transition_up transitions up (in the direction from STATE_ATTACHED
 * to STATE_CONFIGURED) from the specified initial state to the specified final
 * state, passing through each intermediate state on the way.  If the initial
 * state is at or above (i.e. nearer to STATE_CONFIGURED) the final state, then
 * no state transitions will take place.
 *
 * udc_state_transition_down transitions down (in the direction from
 * STATE_CONFIGURED to STATE_ATTACHED) from the specified initial state to the
 * specified final state, passing through each intermediate state on the way.
 * If the initial state is at or below (i.e. nearer to STATE_ATTACHED) the final
 * state, then no state transitions will take place.
 *
 */
 
static void mpc8xx_udc_state_transition_up (usb_device_state_t initial,
				     usb_device_state_t final)
{		
	if (initial < final) {
		switch (initial) {
		case STATE_ATTACHED:
			usbd_device_event_irq (udc_device,
					       DEVICE_HUB_CONFIGURED, 0);
			if (final == STATE_POWERED)
				break;
		case STATE_POWERED:
			usbd_device_event_irq (udc_device, DEVICE_RESET, 0);
			if (final == STATE_DEFAULT)
				break;
		case STATE_DEFAULT:
			usbd_device_event_irq (udc_device,
					       DEVICE_ADDRESS_ASSIGNED, 0);
			if (final == STATE_ADDRESSED)
				break;
		case STATE_ADDRESSED:
			usbd_device_event_irq (udc_device, DEVICE_CONFIGURED,
					       0);
		case STATE_CONFIGURED:
			break;
		default:
			break;
		}
	}
}

static void mpc8xx_udc_state_transition_down (usb_device_state_t initial,
				       usb_device_state_t final)
{
	if (initial > final) {
		switch (initial) {
		case STATE_CONFIGURED:
			usbd_device_event_irq (udc_device, 
					DEVICE_DE_CONFIGURED, 0);
			if (final == STATE_ADDRESSED)
				break;
		case STATE_ADDRESSED:
			usbd_device_event_irq (udc_device, DEVICE_RESET, 0);
			if (final == STATE_DEFAULT)
				break;
		case STATE_DEFAULT:
			usbd_device_event_irq (udc_device, 
					DEVICE_POWER_INTERRUPTION, 0);
			if (final == STATE_POWERED)
				break;
		case STATE_POWERED:
			usbd_device_event_irq (udc_device, DEVICE_HUB_RESET,
				       	0);
		case STATE_ATTACHED:
			break;
		default:
			break;
		}
	}
}

/* mpc8xx_udc_stall
 *
 * Force returning of STALL tokens on the given endpoint. Protocol or function
 * STALL conditions are permissable here
 */
static void mpc8xx_udc_stall (unsigned int ep)
{
	usbp->usep[ep] |= STALL_BITMASK;
}

/* mpc8xx_udc_set_nak
 *
 * Force returning of NAK responses for the given endpoint as a kind of very
 * simple flow control
 */ 
static void mpc8xx_udc_set_nak (unsigned int ep)
{
	usbp->usep[ep] |= NAK_BITMASK;
	__asm__ ("eieio");
}

/* mpc8xx_udc_handle_txerr
 *
 * Handle errors relevant to TX. Return a status code to allow calling
 * indicative of what if anything happened
 */
static short mpc8xx_udc_handle_txerr()
{
	short ep = 0, ret = 0;
	
	for(; ep<TX_RING_SIZE; ep++){
		if(usbp->usber&(0x10<<ep)){
			
			/* Timeout or underrun */
			if(tx_cbd[ep]->cbd_sc&0x06){
				ret = 1;
				mpc8xx_udc_flush_tx_fifo(ep);

			}else{
				if(usbp->usep[ep]&STALL_BITMASK){
					if(!ep){
						usbp->usep[ep]&=
							~STALL_BITMASK;
					}
				}/* else NAK */
			}
			usbp->usber|=(0x10<<ep);
		}
	}
	return ret;
}

/* mpc8xx_udc_advance_rx
 *
 * Advance cbd rx
 */
static void mpc8xx_udc_advance_rx(volatile cbd_t ** rx_cbdp, int epid)
{
	if((*rx_cbdp)->cbd_sc & RX_BD_W){
		*rx_cbdp  = (volatile cbd_t*)
			(endpoints[epid]->rbase + CFG_IMMR);
			
	}else{
		(*rx_cbdp)++;
	}
}


/* mpc8xx_udc_flush_tx_fifo
 *
 * Flush a given TX fifo. Assumes one tx cbd per endpoint
 */
static void mpc8xx_udc_flush_tx_fifo(int epid)
{	
	volatile cbd_t * tx_cbdp = 0;

	if(epid > MAX_ENDPOINTS){
		return;
	}

	/* TX stop */
	immr->im_cpm.cp_cpcr = ((epid<<2) | 0x1D01);
	__asm__ ("eieio");
	while(immr->im_cpm.cp_cpcr & 0x01);
	
	usbp->uscom = 0x40 | 0;
	
	/* reset ring */
	tx_cbdp = (cbd_t*)(endpoints[epid]->tbptr + CFG_IMMR);
	tx_cbdp->cbd_sc = (TX_BD_I | TX_BD_W);

		
	endpoints[epid]->tptr = endpoints[epid]->tbase;
	endpoints[epid]->tstate	= 0x00;
	endpoints[epid]->tbcnt	= 0x00;

	/* TX start */
	immr->im_cpm.cp_cpcr = ((epid<<2) | 0x2D01);
	__asm__ ("eieio");
	while(immr->im_cpm.cp_cpcr & 0x01);

	return;
}

/* mpc8xx_udc_flush_rx_fifo
 *
 * For the sake of completeness of the namespace, it seems like
 * a good-design-decision (tm) to include mpc8xx_udc_flush_rx_fifo();
 * If RX_BD_E is true => a driver bug either here or in an upper layer
 * not polling frequently enough. If RX_BD_E is true we have told the host
 * we have accepted data but, the CPM found it had no-where to put that data
 * which needless to say would be a bad thing.
 */
static void mpc8xx_udc_flush_rx_fifo()
{
	int i = 0;
	for(i = 0;i<RX_RING_SIZE; i++){
		if(!(rx_cbd[i]->cbd_sc&RX_BD_E)){
			ERR("buf %p used rx data len = 0x%x sc=0x%x!\n",
				rx_cbd[i], rx_cbd[i]->cbd_datlen, 
				rx_cbd[i]->cbd_sc);

		}
	}
	ERR("BUG : Input over-run\n");	
}

/* mpc8xx_udc_clear_rxbd
 * 
 * Release control of RX CBD to CP.
 */
static void mpc8xx_udc_clear_rxbd(volatile cbd_t * rx_cbdp)
{
	rx_cbdp->cbd_datlen = 0x0000;
	rx_cbdp->cbd_sc= ((rx_cbdp->cbd_sc & RX_BD_W)|(RX_BD_E | RX_BD_I));
	__asm__ ("eieio");
}

/* mpc8xx_udc_tx_irq
 *
 * Parse for tx timeout, control RX or USB reset/busy conditions
 * Return -1 on timeout, -2 on fatal error, else return zero
 */
static int mpc8xx_udc_tx_irq(int ep)
{
	int i = 0;

	if(usbp->usber&(USB_TX_ERRMASK)){
		if(mpc8xx_udc_handle_txerr()){
			/* Timeout, controlling function must retry send */
			return -1;
		}
	}

	if(usbp->usber & (USB_E_RESET|USB_E_BSY)){
		/* Fatal, abandon TX transaction */
		return -2;
	}
	
	if(usbp->usber & USB_E_RXB){
		for(i = 0;i<RX_RING_SIZE; i++){
			if(!(rx_cbd[i]->cbd_sc&RX_BD_E)){
				if((rx_cbd[i] == ep_ref[0].prx) || ep){
					return -2;	
				}
			}
		}
	}

	return 0;
}

/* mpc8xx_udc_ep_tx
 *
 * Transmit in a re-entrant fashion outbound USB packets.
 * Implement retry/timeout mechanism described in USB specification
 * Toggle DATA0/DATA1 pids as necessary
 * Introduces non-standard tx_retry. The USB standard has no scope for slave
 * devices to give up TX, however tx_retry stops us getting stuck in an endless
 * TX loop.
 */
static int mpc8xx_udc_ep_tx (struct usb_endpoint_instance *epi) 
{
	struct urb *urb = epi->tx_urb;
	volatile cbd_t * tx_cbdp = 0;
	unsigned int ep = 0, pkt_len = 0, x = 0, tx_retry = 0;
	int ret = 0;
	
	if(!epi || (epi->endpoint_address&0x03)>=MAX_ENDPOINTS || !urb){
		return -1;
	}

	ep = epi->endpoint_address & 0x03;
	tx_cbdp = (cbd_t*)(endpoints[ep]->tbptr + CFG_IMMR);
		
	if(tx_cbdp->cbd_sc&TX_BD_R || usbp->usber&USB_E_TXB){
		mpc8xx_udc_flush_tx_fifo(ep);
		usbp->usber |= USB_E_TXB;
	};

	while(tx_retry++ < 100){
		ret = mpc8xx_udc_tx_irq(ep);
		if(ret == -1){
			/* ignore timeout here */
		}else if(ret == -2){
			/* Abandon TX */
			mpc8xx_udc_flush_tx_fifo(ep);	
			return -1;
		}	

		tx_cbdp = (cbd_t*)(endpoints[ep]->tbptr + CFG_IMMR);
		while(tx_cbdp->cbd_sc&TX_BD_R){};
		tx_cbdp->cbd_sc = (tx_cbdp->cbd_sc&TX_BD_W);
	
		pkt_len = urb->actual_length - epi->sent;

		if(pkt_len> epi->tx_packetSize || pkt_len > EP_MAX_PKT){
			pkt_len = MIN(epi->tx_packetSize, EP_MAX_PKT);
		}

		for(x=0; x<pkt_len; x++){
			*((unsigned char*)(tx_cbdp->cbd_bufaddr+x)) = 
				urb->buffer[epi->sent + x];
		}
		tx_cbdp->cbd_datlen = pkt_len;
		tx_cbdp->cbd_sc|=(CBD_TX_BITMASK | ep_ref[ep].pid);
		__asm__ ("eieio");

		#ifdef __SIMULATE_ERROR__
			if(++err_poison_test == 2){
				err_poison_test = 0;
				tx_cbdp->cbd_sc&=~TX_BD_TC;
			}
		#endif

		usbp->uscom = (USCOM_STR | ep); 

		while(!(usbp->usber&USB_E_TXB)){
			ret = mpc8xx_udc_tx_irq(ep);
			if(ret == -1){
				/* TX timeout */
				break;
			}else if(ret == -2){
				if(usbp->usber & USB_E_TXB){
					usbp->usber|=USB_E_TXB;
				}
				mpc8xx_udc_flush_tx_fifo(ep);	
				return -1;
			}
		};

		if(usbp->usber & USB_E_TXB){
			usbp->usber|=USB_E_TXB;
		}

		/* ACK must be present <= 18bit times from TX */
		if(ret == -1){
			continue;
		}
	
		/* TX ACK : USB 2.0 8.7.2, Toggle PID, Advance TX */
		epi->sent += pkt_len;
		epi->last = MIN (urb->actual_length - epi->sent, 
				epi->tx_packetSize);
		TOGGLE_TX_PID(ep_ref[ep].pid);

		if(epi->sent >= epi->tx_urb->actual_length){
			
			epi->tx_urb->actual_length = 0;
			epi->sent = 0;
			
			if(ep_ref[ep].sc & EP_SEND_ZLP){
				ep_ref[ep].sc &= ~EP_SEND_ZLP;
			}else{
				return 0;
			}
		}
	}
	
	ERR("TX fail, endpoint 0x%x tx bytes 0x%x/0x%x\n",ep, epi->sent,
		epi->tx_urb->actual_length);

	return -1;
}

/* mpc8xx_udc_dump_request
 *
 * Dump a control request to console
 */
static void mpc8xx_udc_dump_request(struct usb_device_request *request)
{
	DBG(
	"bmRequestType:%02x bRequest:%02x wValue:%04x "
	"wIndex:%04x wLength:%04x ?\n",
		request->bmRequestType,
		request->bRequest,
		request->wValue,
		request->wIndex,
		request->wLength);

	return;
}

/* mpc8xx_udc_ep0_rx_setup 
 * 
 * Decode received ep0 SETUP packet. return non-zero on error
 */
static int mpc8xx_udc_ep0_rx_setup (volatile cbd_t * rx_cbdp)
{
	unsigned int x = 0;
	struct urb * purb = ep_ref[0].urb;
	struct usb_endpoint_instance *epi = 
		&udc_device->bus->endpoint_array[0];

	for(; x<rx_cbdp->cbd_datlen; x++){
		*(((unsigned char*)&ep_ref[0].urb->device_request)+x) = 
			*((unsigned char*)(rx_cbdp->cbd_bufaddr+x));
	}
	
	mpc8xx_udc_clear_rxbd(rx_cbdp);	

	if (ep0_recv_setup(purb)) {
		mpc8xx_udc_dump_request(&purb->device_request);
		return -1;
	}

	if ((purb->device_request.bmRequestType&USB_REQ_DIRECTION_MASK)
	    == USB_REQ_HOST2DEVICE) {

		switch (purb->device_request.bRequest){
			case USB_REQ_SET_ADDRESS:
				/* Send the Status OUT ZLP */
				ep_ref[0].pid = TX_BD_PID_DATA1;
				purb->actual_length = 0;
				mpc8xx_udc_init_tx(epi,purb);
				mpc8xx_udc_ep_tx(epi);
				
				/* Move to the addressed state */
				usbp->usaddr = udc_device->address;
				mpc8xx_udc_state_transition_up(udc_device->device_state,
					STATE_ADDRESSED);
				return 0;

			case USB_REQ_SET_CONFIGURATION:
				if(!purb->device_request.wValue){
					
					/* Respond at default address */
					usbp->usaddr = 0x00;	
					mpc8xx_udc_state_transition_down(udc_device->device_state,
						STATE_ADDRESSED);

				} else {
					
					/* TODO: Support multiple configurations */
					mpc8xx_udc_state_transition_up(udc_device->device_state,STATE_CONFIGURED);
					for(x=1; x<MAX_ENDPOINTS; x++){
						if((udc_device->bus->endpoint_array[x].endpoint_address&USB_ENDPOINT_DIR_MASK) 
							== USB_DIR_IN){
							ep_ref[x].pid = TX_BD_PID_DATA0;
						}else{
							ep_ref[x].pid = RX_BD_PID_DATA0;
						}
						/* Set configuration must unstall endpoints */
						usbp->usep[x]&=~STALL_BITMASK;
					}

				}
				break;
			default:
				/* CDC/Vendor specific */
				break;
		}

		/* Send ZLP as ACK in Status OUT phase */
		ep_ref[0].pid = TX_BD_PID_DATA1;
		purb->actual_length = 0;
		mpc8xx_udc_init_tx(epi,purb);
		mpc8xx_udc_ep_tx(epi);

	}else{
		if(purb->actual_length){
			ep_ref[0].pid = TX_BD_PID_DATA1;
			mpc8xx_udc_init_tx(epi,purb);

			if(!(purb->actual_length%EP0_MAX_PACKET_SIZE)){
				ep_ref[0].sc |= EP_SEND_ZLP;
			}

			if(purb->device_request.wValue==
					USB_DESCRIPTOR_TYPE_DEVICE){
				if(le16_to_cpu(purb->device_request.wLength)>
						purb->actual_length){
					/* Send EP0_MAX_PACKET_SIZE bytes
					 * unless correct size requested.
					 */
					if(purb->actual_length > 
							epi->tx_packetSize){
						
						purb->actual_length =
							epi->tx_packetSize;
					}
					
				}
			}
			mpc8xx_udc_ep_tx(epi);

		}else{
			/* Corrupt SETUP packet? */
			ERR("Zero length data or SETUP with DATA-IN phase ?\n");
			return 1;
		}
	}
	return 0;
}

/* mpc8xx_udc_init_tx
 *
 * Setup some basic parameters for a TX transaction
 */
static void mpc8xx_udc_init_tx(struct usb_endpoint_instance *epi, 
		struct urb * tx_urb)
{
	epi->sent = 0;
	epi->last = 0;
	epi->tx_urb = tx_urb;
}

/* mpc8xx_udc_ep0_rx
 *
 * Receive ep0/control USB data. Parse and possibly send a response.
 */
static void mpc8xx_udc_ep0_rx(volatile cbd_t * rx_cbdp)
{
	if(rx_cbdp->cbd_sc&RX_BD_PID_SETUP){
		
		/* Unconditionally accept SETUP packets */
		if(mpc8xx_udc_ep0_rx_setup(rx_cbdp)){
			mpc8xx_udc_stall (0);	
		}
		
	} else {
		
		mpc8xx_udc_clear_rxbd(rx_cbdp);
		
		if((rx_cbdp->cbd_datlen-2)){
			/* SETUP with a DATA phase
		 	 * outside of SETUP packet.
		 	 * Reply with STALL.
		 	 */
			mpc8xx_udc_stall (0);
		}
	}
}

/* mpc8xx_udc_epn_rx
 *
 * Receive some data from cbd into USB system urb data abstraction
 * Upper layers should NAK if there is insufficient RX data space 
 */
static int mpc8xx_udc_epn_rx (unsigned int epid, volatile cbd_t * rx_cbdp)
{
	struct usb_endpoint_instance *epi = 0;
	struct urb *urb = 0;
	unsigned int x = 0;

	if(epid >= MAX_ENDPOINTS || !rx_cbdp->cbd_datlen){
		return 0;
	}
	
	/* USB 2.0 PDF section 8.6.4 
	 * Discard data with invalid PID it is a resend.
	 */
	if(ep_ref[epid].pid!=(rx_cbdp->cbd_sc&0xC0)){
		return 1;
	}
	TOGGLE_RX_PID(ep_ref[epid].pid);
	
	epi = &udc_device->bus->endpoint_array[epid];
	urb = epi->rcv_urb;

	for(; x<(rx_cbdp->cbd_datlen-2); x++){
		*((unsigned char*)(urb->buffer + urb->actual_length +x)) =
			*((unsigned char*)(rx_cbdp->cbd_bufaddr+x));
	}

	if(x){
		usbd_rcv_complete (epi, x, 0);
		if(ep_ref[epid].urb->status == RECV_ERROR){
			DBG("RX error unset NAK\n");
			udc_unset_nak(epid);
		}
	}	
	return x;
}

/* mpc8xx_udc_clock_init
 *
 * Obtain a clock reference for Full Speed Signaling 
 */
static void mpc8xx_udc_clock_init (volatile immap_t * immr, 
                                   volatile cpm8xx_t * cp)
{

#if defined(CFG_USB_EXTC_CLK)

	/* This has been tested with a 48MHz crystal on CLK6 */
	switch(CFG_USB_EXTC_CLK){
		case 1:
			immr->im_ioport.iop_papar|= 0x0100;
			immr->im_ioport.iop_padir&= ~0x0100;
			cp->cp_sicr|= 0x24;
			break;
		case 2:
		 	immr->im_ioport.iop_papar|= 0x0200;
			immr->im_ioport.iop_padir&= ~0x0200;
			cp->cp_sicr|= 0x2D; 
			break;
		case 3:
			immr->im_ioport.iop_papar|= 0x0400;
			immr->im_ioport.iop_padir&= ~0x0400;
			cp->cp_sicr|= 0x36; 
			break;
		case 4:
			immr->im_ioport.iop_papar|= 0x0800;
			immr->im_ioport.iop_padir&= ~0x0800;
			cp->cp_sicr|= 0x3F; 
			break;
		default:
			udc_state = STATE_ERROR;
			break;
	}

#elif defined(CFG_USB_BRGCLK)

	/* This has been tested with brgclk == 50MHz */	
	DECLARE_GLOBAL_DATA_PTR;
	int divisor = 0;

	if(gd->cpu_clk<48000000L){
		ERR("brgclk is too slow for full-speed USB!\n");
		udc_state = STATE_ERROR;
		return;
	}

	/* Assume the brgclk is 'good enough', we want !(gd->cpu_clk%48Mhz)
	 * but, can /probably/ live with close-ish alternative rates.
	 */	
	divisor = (gd->cpu_clk/48000000L)-1;
	cp->cp_sicr &= ~0x0000003F;
		
	switch(CFG_USB_BRGCLK){
		case 1:
			cp->cp_brgc1 |= (divisor|CPM_BRG_EN);
			cp->cp_sicr &= ~0x2F;
			break;
		case 2:
			cp->cp_brgc2 |= (divisor|CPM_BRG_EN);
			cp->cp_sicr  |= 0x00000009;
			break;
		case 3:
			cp->cp_brgc3 |= (divisor|CPM_BRG_EN);
			cp->cp_sicr  |= 0x00000012;
			break;
		case 4:
			cp->cp_brgc4 = (divisor|CPM_BRG_EN);
			cp->cp_sicr  |= 0x0000001B; 
			break;
		default:
			udc_state = STATE_ERROR;
			break;
	}

#else
	#error "CFG_USB_EXTC_CLK or CFG_USB_BRGCLK must be defined"
#endif

}

/* mpc8xx_udc_cbd_attach
 *
 * attach a cbd to and endpoint
 */
static void mpc8xx_udc_cbd_attach (int ep, uchar tx_size, uchar rx_size)
{
	
	if (!tx_cbd[ep] || !rx_cbd[ep] || ep >= MAX_ENDPOINTS){
		udc_state = STATE_ERROR;
		return;
	}

	if (tx_size>USB_MAX_PKT || rx_size>USB_MAX_PKT ||
		(!tx_size && !rx_size)){
		udc_state = STATE_ERROR;
		return;
	}

	/* Attach CBD to appropiate Parameter RAM Endpoint data structure */
	if(rx_size){
		endpoints[ep]->rbase = (u32)rx_cbd[rx_ct];
		endpoints[ep]->rbptr = (u32)rx_cbd[rx_ct];
		rx_ct++;

		if(!ep){
			
			endpoints[ep]->rbptr = (u32)rx_cbd[rx_ct];	
			rx_cbd[rx_ct]->cbd_sc |= RX_BD_W;
			rx_ct++;

		}else{
			rx_ct += 2;
			endpoints[ep]->rbptr = (u32)rx_cbd[rx_ct];	
			rx_cbd[rx_ct]->cbd_sc |= RX_BD_W;
			rx_ct++;
		}

		/* Where we expect to RX data on this endpoint */
		ep_ref[ep].prx = rx_cbd[rx_ct-1];
	}else{

		ep_ref[ep].prx = 0;
		endpoints[ep]->rbase = 0;
		endpoints[ep]->rbptr = 0;
	}

	if(tx_size){
		endpoints[ep]->tbase = (u32)tx_cbd[tx_ct];
		endpoints[ep]->tbptr = (u32)tx_cbd[tx_ct];
		tx_ct++;
	}else{
		endpoints[ep]->tbase = 0;
		endpoints[ep]->tbptr = 0;
	}

	endpoints[ep]->tstate = 0;
	endpoints[ep]->tbcnt = 0;
	endpoints[ep]->mrblr = EP_MAX_PKT;
	endpoints[ep]->rfcr = 0x18;	
	endpoints[ep]->tfcr = 0x18;
	ep_ref[ep].sc |= EP_ATTACHED;

	DBG("ep %d rbase 0x%08x rbptr 0x%08x tbase 0x%08x tbptr 0x%08x prx = %p\n",
		ep, endpoints[ep]->rbase, endpoints[ep]->rbptr, endpoints[ep]->tbase,
			endpoints[ep]->tbptr, ep_ref[ep].prx);

	return;
}

/* mpc8xx_udc_cbd_init
 *
 * Allocate space for a cbd and allocate TX/RX data space
 */
static void mpc8xx_udc_cbd_init (void)
{
	int i = 0;

	for(; i<TX_RING_SIZE; i++){
		tx_cbd[i]= (cbd_t*)
			mpc8xx_udc_alloc(sizeof(cbd_t), sizeof(int));
	}

	for(i=0; i<RX_RING_SIZE; i++){
		rx_cbd[i]= (cbd_t*)
			mpc8xx_udc_alloc(sizeof(cbd_t),sizeof(int));
	}	

	for(i=0; i< TX_RING_SIZE; i++){
		tx_cbd[i]->cbd_bufaddr = 
			mpc8xx_udc_alloc(EP_MAX_PKT, sizeof(int));
			
		tx_cbd[i]->cbd_sc = (TX_BD_I | TX_BD_W);	
		tx_cbd[i]->cbd_datlen = 0x0000;
	}


	for(i=0; i< RX_RING_SIZE; i++){
		rx_cbd[i]->cbd_bufaddr = 
			mpc8xx_udc_alloc(EP_MAX_PKT, sizeof(int));
		rx_cbd[i]->cbd_sc = (RX_BD_I | RX_BD_E);
		rx_cbd[i]->cbd_datlen = 0x0000;

	}

	return;
}

/* mpc8xx_udc_endpoint_init
 *
 * Attach an endpoint to some dpram
 */
static void mpc8xx_udc_endpoint_init (void)
{
	int i = 0;

	for(; i<MAX_ENDPOINTS; i++){
		endpoints[i]= (usb_epb_t*)
			mpc8xx_udc_alloc(sizeof(usb_epb_t) , 32);
	}
}

/* mpc8xx_udc_alloc
 *
 * Grab the address of some dpram 
 */
static u32 mpc8xx_udc_alloc (u32 data_size, u32 alignment)
{
	u32 retaddr = address_base;
	
	while(retaddr%alignment){
		retaddr++;
	}	
	address_base+= data_size;
	
	return retaddr;
}

#endif /* CONFIG_MPC885_FAMILY && CONFIG_USB_DEVICE) */