RE: nRF52840 QSPI XIP read function，qspi can't reinit

bh.niu — Fri, 19 Mar 2021 09:12:07 GMT

I tried your code,then it's ok.

I find the nrf_drv_qspi_init must config without callback handler.

nrf_drv_qspi_init(&config, NULL, NULL);//It's ok

nrf_drv_qspi_init(p_qspi_cfg, qspi_handler, NULL);//It's will stop at while(NRF_QSPI->EVENTS_READY == 0) {};

To make sure the words are aligned, I read the data like this：

/*************************************************************************   
**	function name:	qspi_read 
**	input para:		
**                  
**	input para:		 	
**	return:					                                         
**************************************************************************/
void qspi_read(u8_t *p_data, u32_t addr, u16_t len)
{
    u16_t i;

    for(i=0; i<len; i += 4)
    {
        u32_t tmp_data = *(__IO uint32_t*)(0x12000000 + addr + i);
        if((i+4)>len)
        {
            if((len%4) >= 1)
            {
                p_data[i] = (u8_t)(tmp_data);
            }

            if((len%4) >= 2)
            {
                p_data[i+1] = (u8_t)(tmp_data >> 8);
            }      

            if((len%4) >= 3)
            {
                p_data[i+2] = (u8_t)(tmp_data >> 16);
            }                 
        }
        else
        {
            p_data[i]   = (u8_t)(tmp_data);
            p_data[i+1] = (u8_t)(tmp_data >> 8);
            p_data[i+2] = (u8_t)(tmp_data >> 16);
            p_data[i+3] = (u8_t)(tmp_data >> 24);                
        }
    }   
}

RE: nRF52840 QSPI XIP read function，qspi can't reinit

Simonr — Fri, 19 Mar 2021 07:09:41 GMT

First off, please make sure that all memory access by the QSPI peripheral to external memory devices are word-aligned, as you can only write/read in full words (usually 32 bits). What SDK version are you using?

There was a bug in SDK v15.3 that would result in the CPU hanging without access to the SWD interface, which would be caused by either reading/writing from a specific register or calling the uninit function to reconfigure the QSPI.

The workaround is to trigger the ACTIVATE task of the QSPI peripheral before calling the uninit function as such:

NRF_QSPI->EVENTS_READY = 0;

NRF_QSPI->TASKS_ACTIVATE = 1;

while(NRF_QSPI->EVENTS_READY == 0) {};

Both "done" and "end" is printed. I've included the code with the workaround implemented.

/**
 * Copyright (c) 2016 - 2018, Nordic Semiconductor ASA
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice, this
 *    list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form, except as embedded into a Nordic
 *    Semiconductor ASA integrated circuit in a product or a software update for
 *    such product, must reproduce the above copyright notice, this list of
 *    conditions and the following disclaimer in the documentation and/or other
 *    materials provided with the distribution.
 *
 * 3. Neither the name of Nordic Semiconductor ASA nor the names of its
 *    contributors may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 *
 * 4. This software, with or without modification, must only be used with a
 *    Nordic Semiconductor ASA integrated circuit.
 *
 * 5. Any software provided in binary form under this license must not be reverse
 *    engineered, decompiled, modified and/or disassembled.
 *
 * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS
 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS 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.
 *
 */
/** @file
 * @defgroup qspi_example_main main.c
 * @{
 * @ingroup qspi_example
 *
 * @brief QSPI Example Application main file.
 *
 * This file contains the source code for a sample application using QSPI.
 */

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "nrf_drv_qspi.h"
#include "nrf_delay.h"
#include "app_util_platform.h"
#include "app_error.h"
#include "boards.h"

#include "crc32.h"

#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"
#include "sdk_config.h"

#include "nrf_delay.h"


#define QSPI_STD_CMD_WRSR   0x01
#define QSPI_STD_CMD_RSTEN  0x66
#define QSPI_STD_CMD_RST    0x99


#define QSPI_FLASH_DPM_ENTER_DURATION                   3                              //Duration required to enter DPM, in units of 16us
#define QSPI_FLASH_DPM_EXIT_DURATION                    3                              //Duration required to exit DPM, in units of 16us

static void configure_memory()
{
    uint8_t temporary = 0x40;
    uint32_t err_code;
    nrf_qspi_cinstr_conf_t cinstr_cfg = {
        .opcode    = QSPI_STD_CMD_RSTEN,
        .length    = NRF_QSPI_CINSTR_LEN_1B,
        .io2_level = true,
        .io3_level = true,
        .wipwait   = true,
        .wren      = true
    };

    // Send reset enable
    err_code = nrf_drv_qspi_cinstr_xfer(&cinstr_cfg, NULL, NULL);
    APP_ERROR_CHECK(err_code);

    // Send reset command
    cinstr_cfg.opcode = QSPI_STD_CMD_RST;
    err_code = nrf_drv_qspi_cinstr_xfer(&cinstr_cfg, NULL, NULL);
    APP_ERROR_CHECK(err_code);

    // Switch to qspi mode
    cinstr_cfg.opcode = QSPI_STD_CMD_WRSR;
    cinstr_cfg.length = NRF_QSPI_CINSTR_LEN_2B;
    err_code = nrf_drv_qspi_cinstr_xfer(&cinstr_cfg, &temporary, NULL);
    APP_ERROR_CHECK(err_code);
}

uint32_t GenerateCRC(void *data, uint32_t nSize)
{
    NRF_LOG_INFO("crc of %lx size %d", data, nSize);

    uint32_t i = 0;
    uint32_t nSeg = 32;
    uint32_t nCRC = 0;
    while (i < nSize)
    {
        if ((i + nSeg) > nSize)
        {
            nSeg = nSize - i;
        }

        nCRC = crc32_compute((const uint8_t*)(data + i), nSeg, &nCRC);
        i += nSeg;
    }

    return nCRC;
}

int main(void)
{
    uint32_t err_code;

    err_code = NRF_LOG_INIT(NULL);
    APP_ERROR_CHECK(err_code);

    NRF_LOG_DEFAULT_BACKENDS_INIT();

    NRF_LOG_INFO(""
                 "QSPI write and read example using 24bit addressing mode");

    nrf_drv_qspi_config_t config = NRF_DRV_QSPI_DEFAULT_CONFIG;



    //This delay is to allow for nrfjprog to erase the device after a reboot, otherwise it locks out SWD access, DO NOT REMOVE!
    nrf_delay_ms(2000);



    //Setup QSPI to allow for DPM but with it turned off, set XIP offset to 0x0
    config.phy_if.dpmen = false;
    config.xip_offset = 0x0;
    config.prot_if.dpmconfig = true;
    NRF_QSPI->DPMDUR = (QSPI_FLASH_DPM_EXIT_DURATION << QSPI_DPMDUR_EXIT_Pos) | QSPI_FLASH_DPM_ENTER_DURATION;
    err_code = nrf_drv_qspi_init(&config, NULL, NULL);
    APP_ERROR_CHECK(err_code);
    NRF_LOG_INFO("QSPI example started.");
    configure_memory();

    uint8_t pBuf[64];
    nrf_drv_qspi_read(pBuf, 64, 0x0);

    uint32_t mycrc = GenerateCRC((uint32_t*)0x12000000, 0x1000);
    NRF_LOG_INFO("Got: %lx", mycrc);
    
    //Workaround
    NRF_QSPI->EVENTS_READY = 0;
    NRF_QSPI->TASKS_ACTIVATE = 1;
    while(NRF_QSPI->EVENTS_READY == 0) {};
 


    //This is what causes the issue
    uint32_t nConfig = NRF_QSPI->IFCONFIG1;
    nConfig |= 1U << QSPI_IFCONFIG1_DPMEN_Pos;
    NRF_QSPI->IFCONFIG1 = nConfig;



    //This never executes
    NRF_LOG_INFO("done");

    nrf_drv_qspi_uninit();

    NRF_LOG_INFO("end");

    for (;;)
    {
    }
}

/** @} */

Best regards,

Simon

RE: nRF52840 QSPI XIP read function，qspi can't reinit

bh.niu — Thu, 18 Mar 2021 10:33:31 GMT

Thank you for reply. I tried the way you said, but it still doesn't work。

The reason of MCU halted is because of this code：
u8_t tmp = *(__IO uint8_t*)(0x12000000);

After the MCU halted, if I stop debugging, Keil will pop up such a prompt.

RE: nRF52840 QSPI XIP read function，qspi can't reinit

Simonr — Thu, 18 Mar 2021 10:12:39 GMT

How does your nrf_drv_qspi_uninit() function look? Please be aware of erratum 122 present in nRF52840, so the uninitialization should look something like this:

    *(volatile uint32_t *)0x40029010ul = 1ul;
    *(volatile uint32_t *)0x40029054ul = 1ul;
    nrf_drv_qspi_uninit();

If the problem persists, can you try to explain how the MCU is halted exactly?

Best regards,

Simon