/*********************************************************************** * SEGGER Microcontroller GmbH * * The Embedded Experts * ************************************************************************ * * * (c) SEGGER Microcontroller GmbH * * All rights reserved * * www.segger.com * * * ************************************************************************ * * ************************************************************************ * * * * * Licensing terms * * * * This software may be distributed to your customers free of charge. * * This grant of redistribution does not entitle YOU or enduser to * * receive from SEGGER hard-copy documentation, technical support, * * phone assistance, or enhancements or updates to the Software unless * * a specific agreement clearly states otherwise. * * * * * * THIS SOFTWARE IS PROVIDED BY COPYRIGHT HOLDER "AS IS" AND ANY * * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDER 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. * * * ************************************************************************ -------------------------- END-OF-HEADER ----------------------------- Purpose: Template showing basic device identification. Literature: [1] J-Link User Guide */ /********************************************************************* * * Constants, fixed * ********************************************************************** */ // // Bits & Shifts (ARM) // __constant U32 _DP_CTRL_STAT_BIT_DBGPWRUPREQ = (1 << 30); __constant U32 _DP_CTRL_STAT_BIT_SYSPWRUPREQ = (1 << 28); __constant U32 _DP_CTRL_STAT_BIT_STICKYERR = (1 << 5); /********************************************************************* * * Constants, MCU specific * ********************************************************************** */ __constant U32 _INDEX_AP_TO_USE = 0; // For this template, we expect the core to be connect to AP[0] /********************************************************************* * * Static code * ********************************************************************** */ /********************************************************************* * * _IdentifyTarget * * Function descripton * If JTAG: Identifies target in JTAG chain. * If SWD: Execute JTAG->SWD switching sequence. */ static int _IdentifyTarget(void) { U32 ActTIF; U32 TAPId; U32 TAPIdMask; U32 IRLen; U32 IRPrint; U32 IRPrintMask; int r; ActTIF = JLINK_ActiveTIF; if ((ActTIF == JLINK_TIF_JTAG) || (ActTIF == JLINK_TIF_CJTAG)) { JLINK_SYS_Report("JTAG selected. Identifying JTAG Chain..."); r = JLINK_JTAG_Identify(); if (r < 0) { JLINK_SYS_Report("Error: Scanning JTAG chain failed."); return -1; } JLINK_SYS_Report("JTAG Chain Identified. Connecting to DAP TAP..."); // // The TAP IDCODE is described by ARM as follows: // [31:28] Version. // [27:12] Part number (always 0xBxxx). // [11:01] Manufacturer ID (always 0x23B). // [1] Reserved (always b'1). // Therefore, we check the highest bits of Partnumber and bits 11:0 to verify if it is indeed a TAP. // TAPId = 0x0B000477; // These bits are expected to be set in any TAP IDCODE. However, some devices have been known to not apply to the ARM specifications. TAPIdMask = 0x0F000FFF; // Only take the bits of TAPId into account. IRLen = 4; // IR register length of device to locate. This is 4 for most devices. IRPrint = 0x01; // Value read back from scan chain when writing to IR register. JTAG defines the lower 2 bits only to be b'01. IRPrintMask = 0x0F; // 4-bits are taken into account r = JLINK_JTAG_FindSelectTAP(TAPId, TAPIdMask, IRLen, IRPrint, IRPrintMask); // Also considers manual JTAG TAP position pre-selection if user provided , , ... if (r < 0) { JLINK_SYS_Report("Error: Could not find DAP TAP to use."); return -1; } JLINK_SYS_Report("Successfully connected to selected DAP TAP."); } else { JLINK_SYS_Report("SWD selected. Executing JTAG -> SWD switching sequence."); r = JLINK_CORESIGHT_Configure(""); // Outputs JTAG -> SWD switching sequence and checks if DAPId can be read. if (r < 0) { JLINK_SYS_Report("Error: Could not initialize SWD protocol."); } } return r; } /********************************************************************* * * _ConfigureAP() * * Function description * Configures selected AP for debugging. */ static int _ConfigureAP(U32 Index) { U32 v; int r; // // Select AP and bank to use // v = 0 | (0 << 4) // Select bank 0 (this is default for most casese). | (Index << 24) // Select AP[Index] (AHB-AP) ; JLINK_CORESIGHT_WriteDP(JLINK_CORESIGHT_DP_REG_SELECT, v); // // Initialize DAP for debug use. // v = (2 << 0) // Access size: word | (0 << 4) // No auto increment | (1 << 24) // Reserved | (1 << 25) // Private access | (1 << 29) // MasterType == Debug ; r = JLINK_CORESIGHT_WriteAP(JLINK_CORESIGHT_AP_REG_CTRL, v); if (r < 0) { JLINK_SYS_Report("Error: Failed to configure AP."); return -1; } return 0; } /********************************************************************* * * _InitDAP() * * Function description * Initializes DAP, so JLINK_CORESIGHT_ functions can be used. */ static int _InitDAP(void) { U32 v; int r; int t; // // Clear sticky error flags and power up DAP // v = _DP_CTRL_STAT_BIT_DBGPWRUPREQ | _DP_CTRL_STAT_BIT_SYSPWRUPREQ; if (JLINK_ActiveTIF == JLINK_TIF_JTAG) { v |= _DP_CTRL_STAT_BIT_STICKYERR; } else { JLINK_CORESIGHT_WriteDP(JLINK_CORESIGHT_DP_REG_ABORT, 0x1E); } JLINK_CORESIGHT_WriteDP(JLINK_CORESIGHT_DP_REG_CTRL_STAT, v); // // Wait for power up DAP complete // r = -1; t = JLINK_GetTime() + 500; do { r = JLINK_CORESIGHT_ReadDP(JLINK_CORESIGHT_DP_REG_CTRL_STAT); if (r == -1) { // Any error occurred while reading from the DP, we are done break; } v = r; if (v & (0xF << 28)) { // CSYSPWRUPACK and CDBGPWRUPACK set, so both ports have been completely powered? r = 0; break; } if ((t - JLINK_GetTime()) <= 0) { break; } } while(1); if (r < 0) { JLINK_SYS_Report("Error: Failed to initialize DAP."); return -1; } r = _ConfigureAP(_INDEX_AP_TO_USE); // Finally configure the AP so we can use it. if (r < 0) { return -1; } JLINK_SYS_Report("DAP initialized successfully."); return 0; } /********************************************************************* * * Global functions * ********************************************************************** */ /********************************************************************* * * InitTarget() * * Function description * If present, called right before performing generic connect sequence. * Usually used for targets which need a special connect sequence. * E.g.: TI devices with ICEPick TAP on them where core TAP needs to be enabled via specific ICEPick sequences first * * Return value * >= 0: O.K. * < 0: Error * * Notes * (1) Must not use high-level API functions like JLINK_MEM_ etc. * (2) For target interface JTAG, this device has to setup the JTAG chain + JTAG TAP Ids. */ int InitTarget(void) { int r; U32 v; // // Do basic device identification. // r = _IdentifyTarget(); if (r < 0) { return -1; } r = _InitDAP(); if (r < 0) { return -1; } // // Add device specific handling here. // // ... // return 0; } /*************************** end of file ****************************/