Repostiory containing DAPLink source code with Reset Pin workaround for HANI_IOT board.
Upstream: https://github.com/ARMmbed/DAPLink
Diff: source/daplink/interface/swd_host_ca.c
- Revision:
- 0:01f31e923fe2
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/source/daplink/interface/swd_host_ca.c Tue Apr 07 12:55:42 2020 +0200 @@ -0,0 +1,969 @@ +/** + * @file swd_host.c + * @brief Implementation of swd_host.h + * + * DAPLink Interface Firmware + * Copyright (c) 2009-2019, ARM Limited, All Rights Reserved + * Copyright 2019, Cypress Semiconductor Corporation + * or a subsidiary of Cypress Semiconductor Corporation. + * SPDX-License-Identifier: Apache-2.0 + * + * Licensed under the Apache License, Version 2.0 (the "License"); you may + * not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT + * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#ifdef TARGET_MCU_CORTEX_A + +#include "cmsis_os2.h" +#include "target_config.h" +#include "swd_host.h" +#include "debug_ca.h" +#include "DAP_config.h" +#include "DAP.h" +#include "target_family.h" + +// Default NVIC and Core debug base addresses +// TODO: Read these addresses from ROM. +#define NVIC_Addr (0xe000e000) +#define DBG_Addr (0xe000edf0) + +// AP CSW register, base value +#define CSW_VALUE (0x80000000 | CSW_RESERVED | CSW_MSTRDBG | CSW_HPROT | CSW_DBGSTAT | CSW_PADDRINC) + +// SWD register access +#define SWD_REG_AP (1) +#define SWD_REG_DP (0) +#define SWD_REG_R (1<<1) +#define SWD_REG_W (0<<1) +#define SWD_REG_ADR(a) (a & 0x0c) + +#define CMD_MRC (0xEE100E15) /* 1110 1110 0001 0000 RRRR 1110 0001 0101 */ +#define CMD_MCR (0xEE000E15) /* 1110 1110 0000 0000 RRRR 1110 0001 0101 */ +#define CMD_MSR (0xE12CF000) /* 1110 0001 0010 1100 1111 0000 0000 RRRR */ +#define CMD_MRS (0xE14F0000) /* 1110 0001 0100 1111 RRRR 0000 0000 0000 */ +#define CMD_MOV (0xE1A00000) /* 1110 0001 1010 0000 DDDD 0000 0000 RRRR */ /* D = distination */ + +#define DBGDSCR_HALTED (0x00000001) + +#define SELECT_MEM (0x00000000) /* setting of SELECT access memmory */ +#define SELECT_DBG (0x01000000) /* setting of SELECT access Debug Register */ + +#define MAX_SWD_RETRY 10 +#define MAX_TIMEOUT 100000 // Timeout for syscalls on target + + +typedef struct { + uint32_t select; + uint32_t csw; +} DAP_STATE; + +typedef struct { + uint32_t r[16]; + uint32_t xpsr; +} DEBUG_STATE; + +static DAP_STATE dap_state; +static uint32_t soft_reset = SYSRESETREQ; +static uint32_t select_state = SELECT_MEM; +static volatile uint32_t swd_init_debug_flag = 0; + +/* Add static functions */ +static uint8_t swd_restart_req(void); +static uint8_t swd_enable_debug(void); + +void swd_set_reset_connect(SWD_CONNECT_TYPE type) +{ +} + +void int2array(uint8_t *res, uint32_t data, uint8_t len) +{ + uint8_t i = 0; + + for (i = 0; i < len; i++) { + res[i] = (data >> 8 * i) & 0xff; + } +} + +uint8_t swd_transfer_retry(uint32_t req, uint32_t *data) +{ + uint8_t i, ack; + + for (i = 0; i < MAX_SWD_RETRY; i++) { + ack = SWD_Transfer(req, data); + + // if ack != WAIT + if (ack != DAP_TRANSFER_WAIT) { + return ack; + } + } + + return ack; +} + +void swd_set_soft_reset(uint32_t soft_reset_type) +{ + soft_reset = soft_reset_type; +} + +uint8_t swd_init(void) +{ + //TODO - DAP_Setup puts GPIO pins in a hi-z state which can + // cause problems on re-init. This needs to be investigated + // and fixed. + DAP_Setup(); + PORT_SWD_SETUP(); + return 1; +} + +uint8_t swd_off(void) +{ + PORT_OFF(); + return 1; +} + +// Read debug port register. +uint8_t swd_read_dp(uint8_t adr, uint32_t *val) +{ + uint32_t tmp_in; + uint8_t tmp_out[4]; + uint8_t ack; + uint32_t tmp; + tmp_in = SWD_REG_DP | SWD_REG_R | SWD_REG_ADR(adr); + ack = swd_transfer_retry(tmp_in, (uint32_t *)tmp_out); + *val = 0; + tmp = tmp_out[3]; + *val |= (tmp << 24); + tmp = tmp_out[2]; + *val |= (tmp << 16); + tmp = tmp_out[1]; + *val |= (tmp << 8); + tmp = tmp_out[0]; + *val |= (tmp << 0); + return (ack == 0x01); +} + +// Write debug port register +uint8_t swd_write_dp(uint8_t adr, uint32_t val) +{ + uint32_t req; + uint8_t data[4]; + uint8_t ack; + + switch (adr) { + case DP_SELECT: + if (dap_state.select == val) { + return 1; + } + + dap_state.select = val; + break; + + default: + break; + } + + req = SWD_REG_DP | SWD_REG_W | SWD_REG_ADR(adr); + int2array(data, val, 4); + ack = swd_transfer_retry(req, (uint32_t *)data); + return (ack == 0x01); +} + +// Read access port register. +uint8_t swd_read_ap(uint32_t adr, uint32_t *val) +{ + uint8_t tmp_in, ack; + uint8_t tmp_out[4]; + uint32_t tmp; + uint32_t apsel = adr & 0xff000000; + uint32_t bank_sel = adr & APBANKSEL; + + if (!swd_write_dp(DP_SELECT, apsel | bank_sel)) { + return 0; + } + + tmp_in = SWD_REG_AP | SWD_REG_R | SWD_REG_ADR(adr); + // first dummy read + swd_transfer_retry(tmp_in, (uint32_t *)tmp_out); + ack = swd_transfer_retry(tmp_in, (uint32_t *)tmp_out); + *val = 0; + tmp = tmp_out[3]; + *val |= (tmp << 24); + tmp = tmp_out[2]; + *val |= (tmp << 16); + tmp = tmp_out[1]; + *val |= (tmp << 8); + tmp = tmp_out[0]; + *val |= (tmp << 0); + return (ack == 0x01); +} + +// Write access port register +uint8_t swd_write_ap(uint32_t adr, uint32_t val) +{ + uint8_t data[4]; + uint8_t req, ack; + uint32_t apsel = adr & 0xff000000; + uint32_t bank_sel = adr & APBANKSEL; + + if (!swd_write_dp(DP_SELECT, apsel | bank_sel)) { + return 0; + } + + switch (adr) { + case AP_CSW: + if (dap_state.csw == val) { + return 1; + } + + dap_state.csw = val; + break; + + default: + break; + } + + req = SWD_REG_AP | SWD_REG_W | SWD_REG_ADR(adr); + int2array(data, val, 4); + + if (swd_transfer_retry(req, (uint32_t *)data) != 0x01) { + return 0; + } + + req = SWD_REG_DP | SWD_REG_R | SWD_REG_ADR(DP_RDBUFF); + ack = swd_transfer_retry(req, NULL); + return (ack == 0x01); +} + +uint8_t swd_ca_select_state(uint32_t addr) { + uint8_t tmp_in[4]; + uint32_t work_select_state; + + if ((DEBUG_REGSITER_BASE <= addr) && (addr <= DBGCID3)) { + work_select_state = SELECT_DBG; + } else { + work_select_state = SELECT_MEM; + } + if (select_state != work_select_state) { + // SELECT + select_state = work_select_state; + int2array(tmp_in, select_state, 4); + if (swd_transfer_retry(0x08, (uint32_t *)tmp_in) != 0x01) { + return 0; + } + } + return 1; +} + + +// Write 32-bit word aligned values to target memory using address auto-increment. +// size is in bytes. +static uint8_t swd_write_block(uint32_t address, uint8_t *data, uint32_t size) +{ + uint8_t tmp_in[4], req; + uint32_t size_in_words; + uint32_t i, ack = 0x01; + uint32_t *work_write_data; + + if (size == 0) { + return 0; + } + + size_in_words = size / 4; + + // CSW register + if (!swd_write_ap(AP_CSW, CSW_VALUE | CSW_SIZE32)) { + return 0; + } + + if (swd_ca_select_state(address) == 0) { + return 0; + } + + // TAR write + req = SWD_REG_AP | SWD_REG_W | (1 << 2); + int2array(tmp_in, address, 4); + + if (swd_transfer_retry(req, (uint32_t *)tmp_in) != 0x01) { + return 0; + } + + // DRW write + req = SWD_REG_AP | SWD_REG_W | (3 << 2); + work_write_data = (uint32_t *)data; + for (i = 0; i < size_in_words; i++) { + int2array(tmp_in, *work_write_data, 4); + ack = swd_transfer_retry(req, (uint32_t *)tmp_in); + if (ack != 0x01) { + return 0; + } + work_write_data++; + } + return (ack == 0x01); +} + +// Read target memory. +static uint8_t swd_read_data(uint32_t addr, uint32_t *val) +{ + uint8_t tmp_in[4]; + uint8_t tmp_out[4]; + uint8_t req, ack; + uint32_t tmp; + + if (swd_ca_select_state(addr) == 0) { + return 0; + } + + // put addr in TAR register + int2array(tmp_in, addr, 4); + req = SWD_REG_AP | SWD_REG_W | (1 << 2); + + if (swd_transfer_retry(req, (uint32_t *)tmp_in) != 0x01) { + return 0; + } + + // read data + req = SWD_REG_AP | SWD_REG_R | (3 << 2); + + if (swd_transfer_retry(req, (uint32_t *)tmp_out) != 0x01) { + return 0; + } + + // dummy read + req = SWD_REG_DP | SWD_REG_R | SWD_REG_ADR(DP_RDBUFF); + ack = swd_transfer_retry(req, (uint32_t *)tmp_out); + *val = 0; + tmp = tmp_out[3]; + *val |= (tmp << 24); + tmp = tmp_out[2]; + *val |= (tmp << 16); + tmp = tmp_out[1]; + *val |= (tmp << 8); + tmp = tmp_out[0]; + *val |= (tmp << 0); + return (ack == 0x01); +} + +// Write target memory. +static uint8_t swd_write_data(uint32_t address, uint32_t data) +{ + uint8_t tmp_in[4]; + uint8_t req, ack; + + if (swd_ca_select_state(address) == 0) { + return 0; + } + + // put addr in TAR register + int2array(tmp_in, address, 4); + req = SWD_REG_AP | SWD_REG_W | (1 << 2); + + if (swd_transfer_retry(req, (uint32_t *)tmp_in) != 0x01) { + return 0; + } + + // write data + int2array(tmp_in, data, 4); + req = SWD_REG_AP | SWD_REG_W | (3 << 2); + ack = swd_transfer_retry(req, (uint32_t *)tmp_in); + + return (ack == 0x01) ? 1 : 0; +} + +// Read 32-bit word from target memory. +uint8_t swd_read_word(uint32_t addr, uint32_t *val) +{ + if (!swd_write_ap(AP_CSW, CSW_VALUE | CSW_SIZE32)) { + return 0; + } + + if (!swd_read_data(addr, val)) { + return 0; + } + + return 1; +} + +// Write 32-bit word to target memory. +uint8_t swd_write_word(uint32_t addr, uint32_t val) +{ + if (!swd_write_ap(AP_CSW, CSW_VALUE | CSW_SIZE32)) { + return 0; + } + + if (!swd_write_data(addr, val)) { + return 0; + } + + return 1; +} + +// Read unaligned data from target memory. +// size is in bytes. +uint8_t swd_read_memory(uint32_t address, uint8_t *data, uint32_t size) +{ + uint32_t read_size; + uint32_t* read_data; + + read_size = (size / 4); + read_data = (uint32_t*)data; + /* Write bytes until end */ + while ((read_size > 0)) { + if (!swd_read_data(address, read_data)) { + return 0; + } + address+=4; + read_data++; + read_size--; + } + + return 1; +} + +// Write unaligned data to target memory. +// size is in bytes. +uint8_t swd_write_memory(uint32_t address, uint8_t *data, uint32_t size) +{ + uint32_t n; + + while (size > 3) { + // Limit to auto increment page size + n = TARGET_AUTO_INCREMENT_PAGE_SIZE - (address & (TARGET_AUTO_INCREMENT_PAGE_SIZE - 1)); + if (size < n) { + n = size & 0xFFFFFFFC; // Only count complete words remaining + } + + if (!swd_write_block(address, data, n)) { + return 0; + } + + address += n; + data += n; + size -= n; + } + /* Auto increment is end */ + /* Return the CSW reg value to SIZE8 */ + if (!swd_write_ap(AP_CSW, CSW_VALUE | CSW_SIZE8)) { + return 0; + } + + return 1; +} + +// Execute system call. +static uint8_t swd_write_debug_state(DEBUG_STATE *state) +{ + uint32_t i, status; + + if (!swd_write_dp(DP_SELECT, 0)) { + return 0; + } + + // R0, R1, R2, R3 + for (i = 0; i < 4; i++) { + if (!swd_write_core_register(i, state->r[i])) { + return 0; + } + } + + // R9 + if (!swd_write_core_register(9, state->r[9])) { + return 0; + } + + // R13, R14 + for (i = 13; i < 15; i++) { + if (!swd_write_core_register(i, state->r[i])) { + return 0; + } + } + + // xPSR + /* xPSR write */ + /* write PSR (write r6) */ + if (!swd_write_core_register(6, state->xpsr)) { + return 0; + } + /* MSR (PSR <- r6) */ + if (!swd_write_word(DBGITR, CMD_MSR | (6))) { + return 0; + } + + /* R15(PC) */ + /* MRC R7 */ + if (!swd_write_core_register(7, state->r[15])) { + return 0; + } + /* MOV R15, R7 */ + if (!swd_write_word(DBGITR, CMD_MOV | (15 << 12) | (7))) { + return 0; + } + if (!swd_restart_req()) { + return 0; + } + + // check status + if (!swd_read_dp(DP_CTRL_STAT, &status)) { + return 0; + } + + if (status & (STICKYERR | WDATAERR)) { + return 0; + } + + return 1; +} + +static uint8_t swd_restart_req(void) { + uint32_t val, i, timeout = MAX_TIMEOUT; + /* Clear ITRen */ + if (!swd_read_word(DBGDSCR, &val)) { + return 0; + } + val = val & ~0x00002000; + if (!swd_write_word(DBGDSCR, val)) { + return 0; + } + for (i = 0; i < timeout; i++) { + /* read DBGDSCR */ + if (!swd_read_word(DBGDSCR, &val)) { + return 0; + } + /* wait Clear UND_I, ADABORT_I, SDABORT_I[bit:8-6] and InstrCompl_I[bit24] set to 1 */ + if ((val & 0x010001C0) == 0x01000000) { + break; + } else if (i == (timeout -1)) { + return 0; + } + } + /* DBGDRCR Restart req */ + if (!swd_write_word(DBGDRCR, 0x00000002 )) { + return 0; + } + for (i = 0; i < timeout; i++) { + /* read DBGDSCR */ + if (!swd_read_word(DBGDSCR, &val)) { + return 0; + } + if ((val & 0x00000002) == 0x00000002) { + /* restarted */ + return 1; + } + } + return 0; +} + +static uint8_t swd_enable_debug(void) { + uint32_t val; + if (!swd_read_word(DBGDSCR, &val)) { + return 0; + } + /* DBGDSCR ITRen = 1(ARM instruction enable) */ + /* and ExtDCCmode = 01(stall mode) */ + val = val | 0x00106000; + if (!swd_write_word(DBGDSCR, val)) { + return 0; + } + return 1; +} + +uint8_t swd_read_core_register(uint32_t n, uint32_t *val) +{ + if (!swd_write_word(DBGITR, CMD_MCR | (n << 12))) { + return 0; + } + + if (!swd_read_word(DBGDTRTX, val)){ + return 0; + } + + return 1; +} + +uint8_t swd_write_core_register(uint32_t n, uint32_t val) +{ + if (!swd_write_word(DBGDTRRX, val)){ + return 0; + } + + /* Write MRC */ + if (!swd_write_word(DBGITR, (CMD_MRC | (n << 12)))) { + return 0; + } + + return 1; +} + +static uint8_t swd_wait_until_halted(void) +{ + uint32_t val, i, timeout = MAX_TIMEOUT; + for (i = 0; i < timeout; i++) { + /* read DBGDSCR */ + if (!swd_read_word(DBGDSCR, &val)) { + return 0; + } + + if ((val & DBGDSCR_HALTED) == DBGDSCR_HALTED) { + return 1; + } + osDelay(1); + } + + return 0; +} + +uint8_t swd_flash_syscall_exec(const program_syscall_t *sysCallParam, uint32_t entry, uint32_t arg1, uint32_t arg2, uint32_t arg3, uint32_t arg4, flash_algo_return_t return_type) +{ + DEBUG_STATE state = {{0}, 0}; + // Call flash algorithm function on target and wait for result. + state.r[0] = arg1; // R0: Argument 1 + state.r[1] = arg2; // R1: Argument 2 + state.r[2] = arg3; // R2: Argument 3 + state.r[3] = arg4; // R3: Argument 4 + state.r[9] = sysCallParam->static_base; // SB: Static Base + state.r[13] = sysCallParam->stack_pointer; // SP: Stack Pointer + state.r[14] = sysCallParam->breakpoint; // LR: Exit Point + state.r[15] = entry; // PC: Entry Point + state.xpsr = 0x00000000; // xPSR: T = 1, ISR = 0 + + if (!swd_write_debug_state(&state)) { + return 0; + } + + if (!swd_wait_until_halted()) { + return 0; + } + + if (!swd_enable_debug()) { + return 0; + } + + if (!swd_read_core_register(0, &state.r[0])) { + return 0; + } + + if ( return_type == FLASHALGO_RETURN_POINTER ) { + // Flash verify functions return pointer to byte following the buffer if successful. + if (state.r[0] != (arg1 + arg2)) { + return 0; + } + } + else { + // Flash functions return 0 if successful. + if (state.r[0] != 0) { + return 0; + } + } + + return 1; +} + +// SWD Reset +static uint8_t swd_reset(void) +{ + uint8_t tmp_in[8]; + uint8_t i = 0; + + for (i = 0; i < 8; i++) { + tmp_in[i] = 0xff; + } + + SWJ_Sequence(51, tmp_in); + return 1; +} + +// SWD Switch +static uint8_t swd_switch(uint16_t val) +{ + uint8_t tmp_in[2]; + tmp_in[0] = val & 0xff; + tmp_in[1] = (val >> 8) & 0xff; + SWJ_Sequence(16, tmp_in); + return 1; +} + +// SWD Read ID +static uint8_t swd_read_idcode(uint32_t *id) +{ + uint8_t tmp_in[1]; + uint8_t tmp_out[4]; + tmp_in[0] = 0x00; + SWJ_Sequence(8, tmp_in); + + if (swd_read_dp(0, (uint32_t *)tmp_out) != 0x01) { + return 0; + } + + *id = (tmp_out[3] << 24) | (tmp_out[2] << 16) | (tmp_out[1] << 8) | tmp_out[0]; + return 1; +} + + +uint8_t JTAG2SWD() +{ + uint32_t tmp = 0; + + if (!swd_reset()) { + return 0; + } + + if (!swd_switch(0xE79E)) { + return 0; + } + + if (!swd_reset()) { + return 0; + } + + if (!swd_read_idcode(&tmp)) { + return 0; + } + + return 1; +} + +uint8_t swd_init_debug(void) +{ + uint32_t tmp = 0; + + if (swd_init_debug_flag != 0) { + return 1; + } + swd_init_debug_flag = 1; + + // init dap state with fake values + dap_state.select = 0xffffffff; + dap_state.csw = 0xffffffff; + swd_init(); + // call a target dependant function + // this function can do several stuff before really + // initing the debug + if (g_target_family && g_target_family->target_before_init_debug) { + g_target_family->target_before_init_debug(); + } + + if (!JTAG2SWD()) { + return 0; + } + + if (!swd_write_dp(DP_ABORT, STKCMPCLR | STKERRCLR | WDERRCLR | ORUNERRCLR)) { + return 0; + } + + // Ensure CTRL/STAT register selected in DPBANKSEL + if (!swd_write_dp(DP_SELECT, 0)) { + return 0; + } + + // Power up + if (!swd_write_dp(DP_CTRL_STAT, CSYSPWRUPREQ | CDBGPWRUPREQ)) { + return 0; + } + + do { + if (!swd_read_dp(DP_CTRL_STAT, &tmp)) { + return 0; + } + } while ((tmp & (CDBGPWRUPACK | CSYSPWRUPACK)) != (CDBGPWRUPACK | CSYSPWRUPACK)); + + if (!swd_write_dp(DP_CTRL_STAT, CSYSPWRUPREQ | CDBGPWRUPREQ | TRNNORMAL | MASKLANE)) { + return 0; + } + + // call a target dependant function: + // some target can enter in a lock state + // this function can unlock these targets + if (g_target_family && g_target_family->target_unlock_sequence) { + g_target_family->target_unlock_sequence(); + } + + if (!swd_write_dp(DP_SELECT, 0)) { + return 0; + } + + return 1; +} + +uint8_t swd_uninit_debug(void) +{ + return 1; +} + +uint8_t swd_set_target_state_hw(target_state_t state) +{ + uint32_t val; + swd_init(); + + switch (state) { + case RESET_HOLD: + swd_set_target_reset(1); + break; + + case RESET_RUN: + swd_set_target_reset(1); + osDelay(2); + swd_set_target_reset(0); + osDelay(2); + swd_off(); + break; + + case RESET_PROGRAM: + swd_set_target_reset(1); + osDelay(2); + swd_set_target_reset(0); + osDelay(2); + + if (!swd_init_debug()) { + return 0; + } + + if (!swd_enable_debug()) { + return 0; + } + /* DBGDRCR halt req*/ + val = 0x00000001; + if (!swd_write_word(DBGDRCR, val )) { + return 0; + } + osDelay(2); + if (!swd_wait_until_halted()) { + return 0; + } + + break; + + case NO_DEBUG: + if (!swd_write_word(DBG_HCSR, DBGKEY)) { + return 0; + } + + break; + + case DEBUG: + if (!JTAG2SWD()) { + return 0; + } + + if (!swd_write_dp(DP_ABORT, STKCMPCLR | STKERRCLR | WDERRCLR | ORUNERRCLR)) { + return 0; + } + + // Ensure CTRL/STAT register selected in DPBANKSEL + if (!swd_write_dp(DP_SELECT, 0)) { + return 0; + } + + // Power up + if (!swd_write_dp(DP_CTRL_STAT, CSYSPWRUPREQ | CDBGPWRUPREQ)) { + return 0; + } + + // Enable debug + if (!swd_write_word(DBG_HCSR, DBGKEY | C_DEBUGEN)) { + return 0; + } + + break; + + default: + return 0; + } + + return 1; +} + +uint8_t swd_set_target_state_sw(target_state_t state) +{ + uint32_t val; + swd_init(); + switch (state) { + case RESET_HOLD: + swd_set_target_reset(1); + break; + + case RESET_RUN: + swd_set_target_reset(1); + osDelay(2); + swd_set_target_reset(0); + osDelay(2); + swd_off(); + break; + + case RESET_PROGRAM: + if (!swd_init_debug()) { + return 0; + } + + // Enable debug and halt the core (DHCSR <- 0xA05F0003) + if (!swd_write_word(DBG_HCSR, DBGKEY | C_DEBUGEN | C_HALT)) { + return 0; + } + + // Wait until core is halted + do { + if (!swd_read_word(DBG_HCSR, &val)) { + return 0; + } + } while ((val & S_HALT) == 0); + + // Enable halt on reset + if (!swd_write_word(DBG_EMCR, VC_CORERESET)) { + return 0; + } + + // Perform a soft reset + if (!swd_write_word(NVIC_AIRCR, VECTKEY | soft_reset)) { + return 0; + } + + break; + + case NO_DEBUG: + if (!swd_write_word(DBG_HCSR, DBGKEY)) { + return 0; + } + + break; + + case DEBUG: + if (!JTAG2SWD()) { + return 0; + } + + if (!swd_write_dp(DP_ABORT, STKCMPCLR | STKERRCLR | WDERRCLR | ORUNERRCLR)) { + return 0; + } + + // Ensure CTRL/STAT register selected in DPBANKSEL + if (!swd_write_dp(DP_SELECT, 0)) { + return 0; + } + + // Power up + if (!swd_write_dp(DP_CTRL_STAT, CSYSPWRUPREQ | CDBGPWRUPREQ)) { + return 0; + } + + // Enable debug + if (!swd_write_word(DBG_HCSR, DBGKEY | C_DEBUGEN)) { + return 0; + } + + break; + + default: + return 0; + } + + return 1; +} + +#endif