From 5d747a52ceb2f044793523a887abcf95059596f8 Mon Sep 17 00:00:00 2001 From: Gareth McMullin Date: Mon, 7 Feb 2011 11:00:10 +1300 Subject: Restored old Linux platform and added untested SWDP support. --- src/linux/swdptap.c | 182 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 182 insertions(+) create mode 100644 src/linux/swdptap.c (limited to 'src/linux/swdptap.c') diff --git a/src/linux/swdptap.c b/src/linux/swdptap.c new file mode 100644 index 0000000..1185564 --- /dev/null +++ b/src/linux/swdptap.c @@ -0,0 +1,182 @@ +/* + * This file is part of the Black Magic Debug project. + * + * Copyright (C) 2011 Black Sphere Technologies Ltd. + * Written by Gareth McMullin + * + * 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 3 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, see . + */ + +/* Quick hack for bit-banging SW-DP interface over FT2232. + * Intended as proof of concept, not for production. + */ + +#include +#include +#include + +#include "platform.h" +#include "swdptap.h" + +static struct ftdi_context ftdic; +static int f; + +#define BUF_SIZE 4096 + +int swdptap_init(void) +{ + ftdi_init(&ftdic); + ftdi_set_interface(&ftdic, INTERFACE_A); + f = ftdi_usb_open(&ftdic, FT2232_VID, FT2232_PID); + if(f < 0 && f != -5) { + fprintf(stderr, "unable to open ftdi device: %d (%s)\n", + f, ftdi_get_error_string(&ftdic)); + return -1; + } + printf("ftdi open succeeded(channel 1): %d\n",f); + + ftdi_set_latency_timer(&ftdic, 1); + ftdi_set_baudrate(&ftdic, 10000000); + ftdi_usb_purge_buffers(&ftdic); + + printf("enabling bitbang mode(channel 1)\n"); + assert(ftdi_set_bitmode(&ftdic, 0xAB, BITMODE_BITBANG) == 0); + //assert(ftdi_write_data(&ftdic, "\x86\x00\x00\x80\xA8\xAB", 6) == 6); + ftdi_write_data(&ftdic, "\xAB\xA8", 2); + ftdi_write_data_set_chunksize(&ftdic, BUF_SIZE); + + /* This must be investigated in more detail. + * As described in STM32 Reference Manual... */ + swdptap_reset(); + swdptap_seq_out(0xE79E, 16); /* 0b0111100111100111 */ + swdptap_reset(); + swdptap_seq_out(0, 16); + + return 0; +} + +void swdptap_reset(void) +{ + swdptap_turnaround(0); + /* 50 clocks with TMS high */ + for(int i = 0; i < 50; i++) swdptap_bit_out(1); +} + +void swdptap_turnaround(uint8_t dir) +{ + static uint8_t olddir = 0; + + DEBUG("%s", dir ? "\n-> ":"\n<- "); + + if(dir == olddir) return; + olddir = dir; + + if(dir) /* SWDIO goes to input */ + assert(ftdi_set_bitmode(&ftdic, 0xA3, BITMODE_BITBANG) == 0); + + /* One clock cycle */ + ftdi_write_data(&ftdic, "\xAB\xA8", 2); + + if(!dir) /* SWDIO goes to output */ + assert(ftdi_set_bitmode(&ftdic, 0xAB, BITMODE_BITBANG) == 0); +} + +uint8_t swdptap_bit_in(void) +{ + uint8_t ret; + + //ftdi_read_data(&ftdic, &ret, 1); + ftdi_read_pins(&ftdic, &ret); + //ret &= 0x08; + ftdi_write_data(&ftdic, "\xA1\xA0", 2); + + DEBUG("%x\n", ret); + + return ret & 0x08; +} + +void swdptap_bit_out(uint8_t val) +{ + uint8_t buf[3] = "\xA0\xA1\xA0"; + + DEBUG("%d", val); + + if(val) { + for(int i = 0; i < 3; i++) + buf[i] |= 0x08; + } + ftdi_write_data(&ftdic, buf, 3); +} + +uint32_t swdptap_seq_in(int ticks) +{ + uint32_t index = 1; + uint32_t ret = 0; + + swdptap_turnaround(1); + + while (ticks--) { + if (swdptap_bit_in()) + ret |= index; + index <<= 1; + } + + return ret; +} + +uint8_t swdptap_seq_in_parity(uint32_t *ret, int ticks) +{ + uint32_t index = 1; + uint8_t parity = 0; + *ret = 0; + + swdptap_turnaround(1); + + while (ticks--) { + if (swdptap_bit_in()) { + *ret |= index; + parity ^= 1; + } + index <<= 1; + } + if (swdptap_bit_in()) + parity ^= 1; + + return parity; +} + +void swdptap_seq_out(uint32_t MS, int ticks) +{ + swdptap_turnaround(0); + + while (ticks--) { + swdptap_bit_out(MS & 1); + MS >>= 1; + } +} + +void swdptap_seq_out_parity(uint32_t MS, int ticks) +{ + uint8_t parity = 0; + + swdptap_turnaround(0); + + while (ticks--) { + swdptap_bit_out(MS & 1); + parity ^= MS; + MS >>= 1; + } + swdptap_bit_out(parity & 1); +} + -- cgit v1.2.3