firmware/src_simtrace/simtrace_iso7816.c

/* ----------------------------------------------------------------------------
 *         ATMEL Microcontroller Software Support
 * ----------------------------------------------------------------------------
 * Copyright (c) 2009, Atmel Corporation
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * - Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the disclaimer below.
 *
 * Atmel's name may not be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
 * DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * ----------------------------------------------------------------------------
 */

/*------------------------------------------------------------------------------
 *          Headers
 *------------------------------------------------------------------------------*/

#include "board.h"

#include <string.h>
#include <errno.h>

volatile uint32_t char_stat;

volatile ringbuf sim_rcv_buf = { {0}, 0, 0 };

/*-----------------------------------------------------------------------------
 *          Interrupt routines
 *-----------------------------------------------------------------------------*/
static void Callback_PhoneRST_ISR( uint8_t *pArg, uint8_t status, uint32_t transferred, uint32_t remaining)
{
    printf("rstCB\n\r");
    PIO_EnableIt( &pinPhoneRST ) ;
}
void ISR_PhoneRST( const Pin *pPin)
{
    int ret;
    // FIXME: no printfs in ISRs?
    printf("+++ Int!! %x\n\r", pinPhoneRST.pio->PIO_ISR);
    if ( ((pinPhoneRST.pio->PIO_ISR & pinPhoneRST.mask) != 0)  )
    {
        if(PIO_Get( &pinPhoneRST ) == 0) {
            printf(" 0 ");
        } else {
            printf(" 1 ");
        }
    }

    if ((ret = USBD_Write( PHONE_INT, "R", 1, (TransferCallback)&Callback_PhoneRST_ISR, 0 )) != USBD_STATUS_SUCCESS) {
        TRACE_ERROR("USB err status: %d (%s)\n", ret, __FUNCTION__);
        return;
    }

    /* Interrupt enabled after ATR is sent to phone */
    PIO_DisableIt( &pinPhoneRST ) ;
}

/*
 *  char_stat is zero if no error occured.
 *  Otherwise it is filled with the content of the status register.
 */
void USART1_IrqHandler( void )
{
    uint32_t stat;
    char_stat = 0;
    // Rcv buf full
/*    if((stat & US_CSR_RXBUFF) == US_CSR_RXBUFF) {
        TRACE_DEBUG("Rcv buf full");
        USART_DisableIt(USART1, US_IDR_RXBUFF);
    }
*/
    uint32_t csr = USART_PHONE->US_CSR;

    if (csr & US_CSR_TXRDY) {
        /* transmit buffer empty, nothing to transmit */
    }
    if (csr & US_CSR_RXRDY) {
        stat = (csr&(US_CSR_OVRE|US_CSR_FRAME|
                        US_CSR_PARE|US_CSR_TIMEOUT|US_CSR_NACK|
                        (1<<10)));
        uint8_t c = (USART_PHONE->US_RHR) & 0xFF;
//        printf(" %x", c);

        if (stat == 0 ) {
            /* Fill char into buffer */
            rbuf_write(&sim_rcv_buf, c);
        } else {
            TRACE_DEBUG("e %x st: %x\n", c, stat);
        } /* else: error occured */

        char_stat = stat;
    }
}

/*  FIDI update functions   */
#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))

/* Table 6 from ISO 7816-3 */
static const uint16_t fi_table[] = {
	0, 372, 558, 744, 1116, 1488, 1860, 0,
	0, 512, 768, 1024, 1536, 2048, 0, 0
};

/* Table 7 from ISO 7816-3 */
static const uint8_t di_table[] = {
	0, 1, 2, 4, 8, 16, 0, 0,
	0, 0, 2, 4, 8, 16, 32, 64,
};

/* compute the F/D ratio based on Fi and Di values */
static int compute_fidi_ratio(uint8_t fi, uint8_t di)
{
	uint16_t f, d;
	int ret;

	if (fi >= ARRAY_SIZE(fi_table) ||
	    di >= ARRAY_SIZE(di_table))
		return -EINVAL;

	f = fi_table[fi];
	if (f == 0)
		return -EINVAL;

	d = di_table[di];
	if (d == 0)
		return -EINVAL;

	if (di < 8) 
		ret = f / d;
	else
		ret = f * d;

	return ret;
}

void update_fidi(uint8_t fidi)
{
	int rc;

        uint8_t fi = fidi >> 4;
        uint8_t di = fidi & 0xf;

	rc = compute_fidi_ratio(fi, di);
	if (rc > 0 && rc < 0x400) {
		TRACE_INFO("computed Fi(%u) Di(%u) ratio: %d", fi, di, rc);
/*              make sure UART uses new F/D ratio */
		USART_PHONE->US_CR |= US_CR_RXDIS | US_CR_RSTRX;
		USART_PHONE->US_FIDI = rc & 0x3ff;
		USART_PHONE->US_CR |= US_CR_RXEN | US_CR_STTTO;
	} else
		TRACE_INFO("computed FiDi ratio %d unsupported", rc);
}