OVMS3-idf/components/esp32/psram.c

// Copyright 2013-2016 Espressif Systems (Shanghai) PTE LTD
//
// 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.

#include "esp_types.h"
#include "rom/ets_sys.h"
#include "esp_psram.h"
#include "soc/io_mux_reg.h"
#include "soc/dport_reg.h"
#include "rom/gpio.h"
#include "soc/gpio_sig_map.h"
#include "esp_attr.h"
#include "rom/cache.h"
#include "freertos/FreeRTOS.h"
#include "freertos/timers.h"
#include "freertos/task.h"
#include "string.h"
#include "rom/spi_flash.h"
#include "esp_err.h"
#include "rom/cache.h"
#include "driver/gpio.h"

//Commands for PSRAM chip
#define PSRAM_READ              0x03
#define PSRAM_FAST_READ         0x0B
#define PSRAM_FAST_READ_QUAD    0xEB
#define PSRAM_WRITE             0x02
#define PSRAM_QUAD_WRITE        0x38
#define PSRAM_ENTER_QMODE       0x35
#define PSRAM_EXIT_QMODE        0xF5
#define PSRAM_RESET_EN          0x66
#define PSRAM_RESET             0x99
#define PSRAM_SET_BURST_LEN     0xC0
#define PSRAM_DEVICE_ID         0x9F

#define PSRAM_MFG_ID_M          0xff
#define PSRAM_MFG_ID_S             8
#define PSRAM_MFG_ID_ESPRESSIF  0x5d

#define PSRAM_CLK_IO      17
#define PSRAM_CS_IO       16

typedef enum {
    PSRAM_SPI_1  = 0x1,
    PSRAM_SPI_2,
    PSRAM_SPI_3,
    PSRAM_SPI_MAX ,
} psram_spi_num_t;

static psram_cache_mode_t s_psram_mode = PSRAM_CACHE_MAX;

//For now, we only use F40M + S40M, and we don't have to go through gpio matrix
#define DISABLE_GPIO_MATRIX_FOR_40M   1
static int extra_dummy = 0;

typedef enum {
    PSRAM_CMD_QPI,
    PSRAM_CMD_SPI,
} psram_cmd_mode_t;

typedef struct {
    uint16_t cmd;                /*!< Command value */
    uint16_t cmdBitLen;          /*!< Command byte length*/
    uint32_t *addr;              /*!< Point to address value*/
    uint16_t addrBitLen;         /*!< Address byte length*/
    uint32_t *txData;            /*!< Point to send data buffer*/
    uint16_t txDataBitLen;       /*!< Send data byte length.*/
    uint32_t *rxData;            /*!< Point to recevie data buffer*/
    uint16_t rxDataBitLen;       /*!< Recevie Data byte length.*/
    uint32_t dummyBitLen;
} psram_cmd_t;

static void IRAM_ATTR psram_cache_init(psram_cache_mode_t psram_cache_mode, psram_vaddr_mode_t vaddrmode);

static void psram_clear_spi_fifo(psram_spi_num_t spi_num)
{
    int i;
    for (i = 0; i < 16; i++) {
        WRITE_PERI_REG(SPI_W0_REG(spi_num)+i*4, 0);
    }
}

//set basic SPI write mode
static void psram_set_basic_write_mode(psram_spi_num_t spi_num)
{
    CLEAR_PERI_REG_MASK(SPI_USER_REG(spi_num), SPI_FWRITE_QIO);
    CLEAR_PERI_REG_MASK(SPI_USER_REG(spi_num), SPI_FWRITE_DIO);
    CLEAR_PERI_REG_MASK(SPI_USER_REG(spi_num), SPI_FWRITE_QUAD);
    CLEAR_PERI_REG_MASK(SPI_USER_REG(spi_num), SPI_FWRITE_DUAL);
}
//set QPI write mode
static void psram_set_qio_write_mode(psram_spi_num_t spi_num)
{
    SET_PERI_REG_MASK(SPI_USER_REG(spi_num), SPI_FWRITE_QIO);
    CLEAR_PERI_REG_MASK(SPI_USER_REG(spi_num), SPI_FWRITE_DIO);
    CLEAR_PERI_REG_MASK(SPI_USER_REG(spi_num), SPI_FWRITE_QUAD);
    CLEAR_PERI_REG_MASK(SPI_USER_REG(spi_num), SPI_FWRITE_DUAL);
}
//set QPI read mode
static void psram_set_qio_read_mode(psram_spi_num_t spi_num)
{
    SET_PERI_REG_MASK(SPI_CTRL_REG(spi_num), SPI_FREAD_QIO);
    CLEAR_PERI_REG_MASK(SPI_CTRL_REG(spi_num), SPI_FREAD_QUAD);
    CLEAR_PERI_REG_MASK(SPI_CTRL_REG(spi_num), SPI_FREAD_DUAL);
    CLEAR_PERI_REG_MASK(SPI_CTRL_REG(spi_num), SPI_FREAD_DIO);
}
//set SPI read mode
static void psram_set_basic_read_mode(psram_spi_num_t spi_num)
{
    CLEAR_PERI_REG_MASK(SPI_CTRL_REG(spi_num), SPI_FREAD_QIO);
    CLEAR_PERI_REG_MASK(SPI_CTRL_REG(spi_num), SPI_FREAD_QUAD);
    CLEAR_PERI_REG_MASK(SPI_CTRL_REG(spi_num), SPI_FREAD_DUAL);
    CLEAR_PERI_REG_MASK(SPI_CTRL_REG(spi_num), SPI_FREAD_DIO);
}

//start sending and wait for finishing
static IRAM_ATTR void psram_cmd_start(psram_spi_num_t spi_num, psram_cmd_mode_t cmd_mode)
{
    //get cs1
    CLEAR_PERI_REG_MASK(SPI_PIN_REG(PSRAM_SPI_1), SPI_CS1_DIS_M);
    SET_PERI_REG_MASK(SPI_PIN_REG(PSRAM_SPI_1), SPI_CS0_DIS_M);

    uint32_t wr_mode_backup = (READ_PERI_REG(SPI_USER_REG(spi_num)) >> SPI_FWRITE_DUAL_S) & 0xf;
    uint32_t rd_mode_backup = READ_PERI_REG(SPI_CTRL_REG(spi_num)) & (SPI_FREAD_DIO_M | SPI_FREAD_DUAL_M | SPI_FREAD_QUAD_M | SPI_FREAD_QIO_M);
    if (cmd_mode == PSRAM_CMD_SPI) {
        psram_set_basic_write_mode(spi_num);
        psram_set_basic_read_mode(spi_num);
    } else if (cmd_mode == PSRAM_CMD_QPI) {
        psram_set_qio_write_mode(spi_num);
        psram_set_qio_read_mode(spi_num);
    }

    //WAIT SPI0 IDLE
    //READ THREE TIMES TO MAKE SURE?
    while( READ_PERI_REG(SPI_EXT2_REG(0)) != 0);
    while( READ_PERI_REG(SPI_EXT2_REG(0)) != 0);
    while( READ_PERI_REG(SPI_EXT2_REG(0)) != 0);
    SET_PERI_REG_MASK( DPORT_HOST_INF_SEL_REG, 1<<14);

    // Start send data
    SET_PERI_REG_MASK(SPI_CMD_REG(spi_num), SPI_USR);
    while ((READ_PERI_REG(SPI_CMD_REG(spi_num)) & SPI_USR));

    CLEAR_PERI_REG_MASK(DPORT_HOST_INF_SEL_REG, 1 << 14);

    //recover spi mode
    SET_PERI_REG_BITS(SPI_USER_REG(spi_num), 0xf, wr_mode_backup, SPI_FWRITE_DUAL_S);
    CLEAR_PERI_REG_MASK(SPI_CTRL_REG(spi_num), (SPI_FREAD_DIO_M|SPI_FREAD_DUAL_M|SPI_FREAD_QUAD_M|SPI_FREAD_QIO_M));
    SET_PERI_REG_MASK(SPI_CTRL_REG(spi_num), rd_mode_backup);

    //return cs to cs0
    SET_PERI_REG_MASK(SPI_PIN_REG(PSRAM_SPI_1), SPI_CS1_DIS_M);
    CLEAR_PERI_REG_MASK(SPI_PIN_REG(PSRAM_SPI_1),SPI_CS0_DIS_M);
}

//start sending cmd/addr and receving data
static void IRAM_ATTR psram_recv_start(psram_spi_num_t spi_num, uint32_t* pRxData, uint16_t rxByteLen,
        psram_cmd_mode_t cmd_mode)
{
    //get cs1
    CLEAR_PERI_REG_MASK(SPI_PIN_REG(PSRAM_SPI_1), SPI_CS1_DIS_M);
    SET_PERI_REG_MASK(SPI_PIN_REG(PSRAM_SPI_1), SPI_CS0_DIS_M);

    uint32_t cmd_mode_backup = (READ_PERI_REG(SPI_USER_REG(spi_num)) >> SPI_FWRITE_DUAL_S) & 0xf;
    uint32_t rd_mode_backup = READ_PERI_REG(SPI_CTRL_REG(spi_num)) & (SPI_FREAD_DIO_M | SPI_FREAD_DUAL_M | SPI_FREAD_QUAD_M | SPI_FREAD_QIO_M);
    if (cmd_mode == PSRAM_CMD_SPI) {
        psram_set_basic_write_mode(spi_num);
        psram_set_basic_read_mode(spi_num);
    } else if (cmd_mode == PSRAM_CMD_QPI) {
        psram_set_qio_write_mode(spi_num);
        psram_set_qio_read_mode(spi_num);
    }

    //WAIT SPI0 IDLE
    //READ THREE TIMES TO MAKE SURE?
    while ( READ_PERI_REG(SPI_EXT2_REG(0)) != 0);
    while ( READ_PERI_REG(SPI_EXT2_REG(0)) != 0);
    while ( READ_PERI_REG(SPI_EXT2_REG(0)) != 0);
    SET_PERI_REG_MASK(DPORT_HOST_INF_SEL_REG, 1 << 14);

    // Start send data
    SET_PERI_REG_MASK(SPI_CMD_REG(spi_num), SPI_USR);
    while ((READ_PERI_REG(SPI_CMD_REG(spi_num)) & SPI_USR));
    CLEAR_PERI_REG_MASK(DPORT_HOST_INF_SEL_REG, 1 << 14);

    //recover spi mode
    SET_PERI_REG_BITS(SPI_USER_REG(spi_num), SPI_FWRITE_DUAL_M, cmd_mode_backup, SPI_FWRITE_DUAL_S);
    CLEAR_PERI_REG_MASK(SPI_CTRL_REG(spi_num), (SPI_FREAD_DIO_M|SPI_FREAD_DUAL_M|SPI_FREAD_QUAD_M|SPI_FREAD_QIO_M));
    SET_PERI_REG_MASK(SPI_CTRL_REG(spi_num), rd_mode_backup);

    //return cs to cs0
    SET_PERI_REG_MASK(SPI_PIN_REG(PSRAM_SPI_1), SPI_CS1_DIS_M);
    CLEAR_PERI_REG_MASK(SPI_PIN_REG(PSRAM_SPI_1), SPI_CS0_DIS_M);

    int idx = 0;
    // Read data out
    do {
        *pRxData++ = READ_PERI_REG(SPI_W0_REG(spi_num) + (idx << 2));
    } while (++idx < ((rxByteLen / 4) + ((rxByteLen % 4) ? 1 : 0)));
}

//setup spi command/addr/data/dummy in user mode
static int psram_cmd_config(psram_spi_num_t spi_num, psram_cmd_t* pInData)
{
    while (READ_PERI_REG(SPI_CMD_REG(spi_num)) & SPI_USR);
    // Set command by user.
    if (pInData->cmdBitLen != 0) {
        // Max command length 16 bits.
        SET_PERI_REG_BITS(SPI_USER2_REG(spi_num), SPI_USR_COMMAND_BITLEN, pInData->cmdBitLen - 1,
                SPI_USR_COMMAND_BITLEN_S);
        // Enable command
        SET_PERI_REG_MASK(SPI_USER_REG(spi_num), SPI_USR_COMMAND);
        // Load command,bit15-0 is cmd value.
        SET_PERI_REG_BITS(SPI_USER2_REG(spi_num), SPI_USR_COMMAND_VALUE, pInData->cmd, SPI_USR_COMMAND_VALUE_S);
    } else {
        CLEAR_PERI_REG_MASK(SPI_USER_REG(spi_num), SPI_USR_COMMAND);
        SET_PERI_REG_BITS(SPI_USER2_REG(spi_num), SPI_USR_COMMAND_BITLEN, 0, SPI_USR_COMMAND_BITLEN_S);
    }
    // Set Address by user.
    if (pInData->addrBitLen != 0) {
        SET_PERI_REG_BITS(SPI_USER1_REG(spi_num), SPI_USR_ADDR_BITLEN, (pInData->addrBitLen - 1), SPI_USR_ADDR_BITLEN_S);
        // Enable address
        SET_PERI_REG_MASK(SPI_USER_REG(spi_num), SPI_USR_ADDR);
        // Set address
        //SET_PERI_REG_BITS(SPI_ADDR_REG(spi_num), SPI_USR_ADDR_VALUE, *pInData->addr, SPI_USR_ADDR_VALUE_S);
        WRITE_PERI_REG(SPI_ADDR_REG(spi_num), *pInData->addr);
    } else {
        CLEAR_PERI_REG_MASK(SPI_USER_REG(spi_num), SPI_USR_ADDR);
        SET_PERI_REG_BITS(SPI_USER1_REG(spi_num), SPI_USR_ADDR_BITLEN, 0, SPI_USR_ADDR_BITLEN_S);
    }
    // Set data by user.
    uint32_t* p_tx_val = pInData->txData;
    if (pInData->txDataBitLen != 0) {
        // Enable MOSI
        SET_PERI_REG_MASK(SPI_USER_REG(spi_num), SPI_USR_MOSI);
        // Load send buffer
        int len = (pInData->txDataBitLen + 31) / 32;
        if (p_tx_val != NULL) {
            memcpy((void*)SPI_W0_REG(spi_num), p_tx_val, len * 4);
        }
        // Set data send buffer length.Max data length 64 bytes.
        SET_PERI_REG_BITS(SPI_MOSI_DLEN_REG(spi_num), SPI_USR_MOSI_DBITLEN, (pInData->txDataBitLen - 1),
                SPI_USR_MOSI_DBITLEN_S);
    } else {
        CLEAR_PERI_REG_MASK(SPI_USER_REG(spi_num), SPI_USR_MOSI);
        SET_PERI_REG_BITS(SPI_MOSI_DLEN_REG(spi_num), SPI_USR_MOSI_DBITLEN, 0, SPI_USR_MOSI_DBITLEN_S);
    }
    // Set rx data by user.
    if (pInData->rxDataBitLen != 0) {
        // Enable MOSI
        SET_PERI_REG_MASK(SPI_USER_REG(spi_num), SPI_USR_MISO);
        // Set data send buffer length.Max data length 64 bytes.
        SET_PERI_REG_BITS(SPI_MISO_DLEN_REG(spi_num), SPI_USR_MISO_DBITLEN, (pInData->rxDataBitLen - 1),
                SPI_USR_MISO_DBITLEN_S);
    } else {
        CLEAR_PERI_REG_MASK(SPI_USER_REG(spi_num), SPI_USR_MISO);
        SET_PERI_REG_BITS(SPI_MISO_DLEN_REG(spi_num), SPI_USR_MISO_DBITLEN, 0, SPI_USR_MISO_DBITLEN_S);
    }
    if (pInData->dummyBitLen != 0) {
        SET_PERI_REG_MASK(SPI_USER_REG(PSRAM_SPI_1), SPI_USR_DUMMY); // dummy en
        SET_PERI_REG_BITS(SPI_USER1_REG(PSRAM_SPI_1), SPI_USR_DUMMY_CYCLELEN_V, pInData->dummyBitLen - 1,
                SPI_USR_DUMMY_CYCLELEN_S);  //DUMMY
    } else {
        CLEAR_PERI_REG_MASK(SPI_USER_REG(PSRAM_SPI_1), SPI_USR_DUMMY); // dummy en
        SET_PERI_REG_BITS(SPI_USER1_REG(PSRAM_SPI_1), SPI_USR_DUMMY_CYCLELEN_V, 0, SPI_USR_DUMMY_CYCLELEN_S);  //DUMMY
    }
    return 0;
}

//exit QPI mode(set back to SPI mode)
static void psram_disable_qio_mode(psram_spi_num_t spi_num)
{
    psram_cmd_t ps_cmd;
    uint32_t cmd_exit_qpi;
    switch (s_psram_mode) {
        case PSRAM_CACHE_F80M_S80M:
            cmd_exit_qpi = PSRAM_EXIT_QMODE;
            ps_cmd.txDataBitLen = 8;
            break;
        case PSRAM_CACHE_F80M_S40M:
        case PSRAM_CACHE_F40M_S40M:
        default:
            cmd_exit_qpi = PSRAM_EXIT_QMODE << 8;
            ps_cmd.txDataBitLen = 16;
            break;
    }
    ps_cmd.txData = &cmd_exit_qpi;
    ps_cmd.cmd = 0;
    ps_cmd.cmdBitLen = 0;
    ps_cmd.addr = 0;
    ps_cmd.addrBitLen = 0;
    ps_cmd.rxData = NULL;
    ps_cmd.rxDataBitLen = 0;
    ps_cmd.dummyBitLen = 0;
    psram_cmd_config(spi_num, &ps_cmd);
    psram_cmd_start(spi_num, PSRAM_CMD_QPI);
}

//read psram id
static void psram_read_id(uint32_t* dev_id)
{
    psram_spi_num_t spi_num = PSRAM_SPI_1;
    psram_disable_qio_mode(spi_num);
    uint32_t addr = (PSRAM_DEVICE_ID << 24) | 0;
    uint32_t dummy_bits = 0;
    psram_cmd_t ps_cmd;
    switch (s_psram_mode) {
        case PSRAM_CACHE_F80M_S80M:
            dummy_bits = 0 + extra_dummy;
            ps_cmd.cmdBitLen = 0;
            break;
        case PSRAM_CACHE_F80M_S40M:
        case PSRAM_CACHE_F40M_S40M:
        default:
            dummy_bits = 0 + extra_dummy;
            ps_cmd.cmdBitLen = 2;   //this two bits is used to delay 2 clock cycle
            break;
    }
    ps_cmd.cmd = 0;
    ps_cmd.addr = &addr;
    ps_cmd.addrBitLen = 4 * 8;
    ps_cmd.txDataBitLen = 0;
    ps_cmd.txData = NULL;
    ps_cmd.rxDataBitLen = 4 * 8;
    ps_cmd.rxData = dev_id;
    ps_cmd.dummyBitLen = dummy_bits;
    psram_cmd_config(spi_num, &ps_cmd);
    psram_clear_spi_fifo(spi_num);
    psram_recv_start(spi_num, ps_cmd.rxData, ps_cmd.rxDataBitLen / 8, PSRAM_CMD_SPI);
}

//enter QPI mode
static esp_err_t IRAM_ATTR psram_enable_qio_mode(psram_spi_num_t spi_num)
{
    psram_cmd_t ps_cmd;
    uint32_t addr = (PSRAM_ENTER_QMODE << 24) | 0;
    switch (s_psram_mode) {
        case PSRAM_CACHE_F80M_S80M:
            ps_cmd.cmdBitLen = 0;
            break;
        case PSRAM_CACHE_F80M_S40M:
        case PSRAM_CACHE_F40M_S40M:
        default:
            ps_cmd.cmdBitLen = 2;
            break;
    }
    ps_cmd.cmd = 0;
    ps_cmd.addr = &addr;
    ps_cmd.addrBitLen = 8;
    ps_cmd.txData = NULL;
    ps_cmd.txDataBitLen = 0;
    ps_cmd.rxData = NULL;
    ps_cmd.rxDataBitLen = 0;
    ps_cmd.dummyBitLen = 0;
    psram_cmd_config(spi_num, &ps_cmd);
    psram_cmd_start(spi_num, PSRAM_CMD_SPI);
    return ESP_OK;
}

//spi param init for psram
void IRAM_ATTR psram_spi_init(psram_spi_num_t spi_num, psram_cache_mode_t mode)
{
    uint8_t i, k;
    CLEAR_PERI_REG_MASK(SPI_SLAVE_REG(spi_num), SPI_TRANS_DONE << 5);
    SET_PERI_REG_MASK(SPI_USER_REG(spi_num), SPI_CS_SETUP);
    // SPI_CPOL & SPI_CPHA
    CLEAR_PERI_REG_MASK(SPI_PIN_REG(spi_num), SPI_CK_IDLE_EDGE);
    CLEAR_PERI_REG_MASK(SPI_USER_REG(spi_num), SPI_CK_OUT_EDGE);
    // SPI bit order
    CLEAR_PERI_REG_MASK(SPI_CTRL_REG(spi_num), SPI_WR_BIT_ORDER);
    CLEAR_PERI_REG_MASK(SPI_CTRL_REG(spi_num), SPI_RD_BIT_ORDER);
    // SPI bit order
    CLEAR_PERI_REG_MASK(SPI_USER_REG(spi_num), SPI_DOUTDIN);
    // May be not must to do.
    WRITE_PERI_REG(SPI_USER1_REG(spi_num), 0);
    // SPI mode type
    CLEAR_PERI_REG_MASK(SPI_SLAVE_REG(spi_num), SPI_SLAVE_MODE);
    switch (mode) {
        case PSRAM_CACHE_F80M_S80M:
            WRITE_PERI_REG(SPI_CLOCK_REG(spi_num), SPI_CLK_EQU_SYSCLK); // 80Mhz speed
            break;
        case PSRAM_CACHE_F80M_S40M:
        case PSRAM_CACHE_F40M_S40M:
        default:
            i = (2 / 40) ? (2 / 40) : 1;
            k = 2 / i;
            CLEAR_PERI_REG_MASK(SPI_CLOCK_REG(spi_num), SPI_CLK_EQU_SYSCLK);
            WRITE_PERI_REG(SPI_CLOCK_REG(spi_num),
                    (((i - 1) & SPI_CLKDIV_PRE) << SPI_CLKDIV_PRE_S) |
                    (((k - 1) & SPI_CLKCNT_N) << SPI_CLKCNT_N_S) |
                    ((((k + 1) / 2 - 1) & SPI_CLKCNT_H) << SPI_CLKCNT_H_S) |
                    (((k - 1) & SPI_CLKCNT_L) << SPI_CLKCNT_L_S)); //clear bit 31,set SPI clock div
            break;
    }
    // Enable MOSI
    SET_PERI_REG_MASK(SPI_USER_REG(spi_num), SPI_CS_SETUP | SPI_CS_HOLD | SPI_USR_MOSI);
    memset((void*)SPI_W0_REG(spi_num), 0, 16 * 4);
}

//psram gpio init , different working frequency we have different solutions
esp_err_t IRAM_ATTR psram_enable(psram_cache_mode_t mode, psram_vaddr_mode_t vaddrmode)   //psram init
{
    WRITE_PERI_REG(GPIO_ENABLE_W1TC_REG, BIT(PSRAM_CLK_IO) | BIT(PSRAM_CS_IO));   //DISABLE OUPUT FOR IO16/17
    assert(mode == PSRAM_CACHE_F40M_S40M && "we don't support any other mode for now.");
    s_psram_mode = mode;

    SET_PERI_REG_MASK(DPORT_PERIP_CLK_EN_REG, DPORT_SPI_CLK_EN);
    CLEAR_PERI_REG_MASK(DPORT_PERIP_RST_EN_REG, DPORT_SPI_RST);
    SET_PERI_REG_MASK(DPORT_PERIP_CLK_EN_REG, DPORT_SPI_CLK_EN_1);
    CLEAR_PERI_REG_MASK(DPORT_PERIP_RST_EN_REG, DPORT_SPI_RST_1);
    SET_PERI_REG_MASK(DPORT_PERIP_CLK_EN_REG, DPORT_SPI_CLK_EN_2);
    CLEAR_PERI_REG_MASK(DPORT_PERIP_RST_EN_REG, DPORT_SPI_RST_2);

    WRITE_PERI_REG(SPI_EXT3_REG(0), 0x1);
    CLEAR_PERI_REG_MASK(SPI_USER_REG(PSRAM_SPI_1), SPI_USR_PREP_HOLD_M);

    switch (mode) {
        case PSRAM_CACHE_F80M_S80M:
            psram_spi_init(PSRAM_SPI_1, mode);
            extra_dummy = 2;
            CLEAR_PERI_REG_MASK(SPI_USER_REG(PSRAM_SPI_1), SPI_CS_HOLD);
            gpio_matrix_out(PSRAM_CS_IO, SPICS1_OUT_IDX, 0, 0);
            gpio_matrix_out(PSRAM_CLK_IO, VSPICLK_OUT_IDX, 0, 0);
            //use spi3 clock,but use spi1 data/cs wires
            WRITE_PERI_REG(SPI_ADDR_REG(PSRAM_SPI_3), 32 << 24);
            WRITE_PERI_REG(SPI_CLOCK_REG(PSRAM_SPI_3), SPI_CLK_EQU_SYSCLK_M);   //SET 80M AND CLEAR OTHERS
            SET_PERI_REG_MASK(SPI_CMD_REG(PSRAM_SPI_3), SPI_FLASH_READ_M);
            uint32_t spi_status;
            while (1) {
                spi_status = READ_PERI_REG(SPI_EXT2_REG(PSRAM_SPI_3));
                if (spi_status != 0 && spi_status != 1) {
                    CLEAR_PERI_REG_MASK(DPORT_PERIP_CLK_EN_REG, BIT(PSRAM_CS_IO));   //DPORT_SPI_CLK_EN
                    break;
                }
            }
            break;
        case PSRAM_CACHE_F80M_S40M:
        case PSRAM_CACHE_F40M_S40M:
        default:
#if DISABLE_GPIO_MATRIX_FOR_40M
            extra_dummy = 0;
#else
            extra_dummy = 1;
#endif
            psram_spi_init(PSRAM_SPI_1, mode);
            CLEAR_PERI_REG_MASK(SPI_USER_REG(PSRAM_SPI_1), SPI_CS_HOLD);
            gpio_matrix_out(PSRAM_CS_IO, SPICS1_OUT_IDX, 0, 0);
            gpio_matrix_in(6, SIG_IN_FUNC224_IDX, 0);
            gpio_matrix_out(20, SIG_IN_FUNC224_IDX, 0, 0);
            gpio_matrix_in(20, SIG_IN_FUNC225_IDX, 0);
            gpio_matrix_out(PSRAM_CLK_IO, SIG_IN_FUNC225_IDX, 0, 0);
            break;
    }
    CLEAR_PERI_REG_MASK(SPI_USER_REG(PSRAM_SPI_1), SPI_CS_SETUP_M);

#if (!DISABLE_GPIO_MATRIX_FOR_40M)
    psram_gpio_config(mode);
#endif
    WRITE_PERI_REG(GPIO_ENABLE_W1TS_REG, BIT(PSRAM_CS_IO)| BIT(PSRAM_CLK_IO));
    PIN_FUNC_SELECT(GPIO_PIN_MUX_REG[PSRAM_CS_IO], 2);
    PIN_FUNC_SELECT(GPIO_PIN_MUX_REG[PSRAM_CLK_IO], 2);
    uint32_t id;
    psram_read_id(&id);
    if (((id >> PSRAM_MFG_ID_S) & PSRAM_MFG_ID_M) != PSRAM_MFG_ID_ESPRESSIF) {
        return ESP_FAIL;
    }
    psram_enable_qio_mode(PSRAM_SPI_1);
    psram_cache_init(mode, vaddrmode);
    return ESP_OK;
}

//register initialization for sram cache params and r/w commands
static void IRAM_ATTR psram_cache_init(psram_cache_mode_t psram_cache_mode, psram_vaddr_mode_t vaddrmode)
{
    CLEAR_PERI_REG_MASK(SPI_CLOCK_REG(0), SPI_CLK_EQU_SYSCLK_M);
    SET_PERI_REG_BITS(SPI_CLOCK_REG(0), SPI_CLKDIV_PRE_V, 0, SPI_CLKDIV_PRE_S);
    SET_PERI_REG_BITS(SPI_CLOCK_REG(0), SPI_CLKCNT_N, 1, SPI_CLKCNT_N_S);
    SET_PERI_REG_BITS(SPI_CLOCK_REG(0), SPI_CLKCNT_H, 0, SPI_CLKCNT_H_S);
    SET_PERI_REG_BITS(SPI_CLOCK_REG(0), SPI_CLKCNT_L, 1, SPI_CLKCNT_L_S);

    switch (psram_cache_mode) {
        case PSRAM_CACHE_F80M_S80M:
            CLEAR_PERI_REG_MASK(SPI_DATE_REG(0), BIT(31));   //flash 1 div clk,80+40;
            CLEAR_PERI_REG_MASK(SPI_DATE_REG(0), BIT(30)); //pre clk div , ONLY IF SPI/SRAM@ DIFFERENT SPEED,JUST FOR SPI0. FLASH DIV 2+SRAM DIV4
            WRITE_PERI_REG(SPI_CLOCK_REG(0), SPI_CLK_EQU_SYSCLK_M);   //SET 1DIV CLOCK AND RESET OTHER PARAMS
            SET_PERI_REG_MASK(SPI_CACHE_SCTRL_REG(0), SPI_USR_RD_SRAM_DUMMY_M);   //enable cache read dummy
            SET_PERI_REG_BITS(SPI_CACHE_SCTRL_REG(0), SPI_SRAM_DUMMY_CYCLELEN_V, 3 + extra_dummy,
                    SPI_SRAM_DUMMY_CYCLELEN_S); //dummy, psram cache :  40m--+1dummy,80m--+2dummy
            SET_PERI_REG_MASK(SPI_CACHE_SCTRL_REG(0), SPI_CACHE_SRAM_USR_RCMD_M); //enable user mode for cache read command
            break;
        case PSRAM_CACHE_F80M_S40M:
            SET_PERI_REG_MASK(SPI_DATE_REG(0), BIT(31)); //flash 1 div clk
            CLEAR_PERI_REG_MASK(SPI_DATE_REG(0), BIT(30)); //pre clk div , ONLY IF SPI/SRAM@ DIFFERENT SPEED,JUST FOR SPI0.
            SET_PERI_REG_MASK(SPI_CACHE_SCTRL_REG(0), SPI_USR_RD_SRAM_DUMMY_M); //enable cache read dummy
            SET_PERI_REG_BITS(SPI_CACHE_SCTRL_REG(0), SPI_SRAM_DUMMY_CYCLELEN_V, 3 + extra_dummy,
                    SPI_SRAM_DUMMY_CYCLELEN_S); //dummy, psram cache :  40m--+1dummy,80m--+2dummy
            SET_PERI_REG_MASK(SPI_CACHE_SCTRL_REG(0), SPI_CACHE_SRAM_USR_RCMD_M); //enable user mode for cache read command
            break;
        case PSRAM_CACHE_F40M_S40M:
        default:
            CLEAR_PERI_REG_MASK(SPI_DATE_REG(0), BIT(31)); //flash 1 div clk
            CLEAR_PERI_REG_MASK(SPI_DATE_REG(0), BIT(30)); //pre clk div
            SET_PERI_REG_MASK(SPI_CACHE_SCTRL_REG(0), SPI_USR_RD_SRAM_DUMMY_M); //enable cache read dummy
            SET_PERI_REG_BITS(SPI_CACHE_SCTRL_REG(0), SPI_SRAM_DUMMY_CYCLELEN_V, 3 + extra_dummy,
                    SPI_SRAM_DUMMY_CYCLELEN_S); //dummy, psram cache :  40m--+1dummy,80m--+2dummy
            SET_PERI_REG_MASK(SPI_CACHE_SCTRL_REG(0), SPI_CACHE_SRAM_USR_RCMD_M); //enable user mode for cache read command
            break;
    }
    SET_PERI_REG_MASK(SPI_CACHE_SCTRL_REG(0), SPI_CACHE_SRAM_USR_WCMD_M);     // cache write command enable
    SET_PERI_REG_BITS(SPI_CACHE_SCTRL_REG(0), SPI_SRAM_ADDR_BITLEN_V, 23, SPI_SRAM_ADDR_BITLEN_S); //write address for cache command.
    SET_PERI_REG_MASK(SPI_CACHE_SCTRL_REG(0), SPI_USR_SRAM_QIO_M);     //enable qio mode for cache command
    CLEAR_PERI_REG_MASK(SPI_CACHE_SCTRL_REG(0), SPI_USR_SRAM_DIO_M);     //disable dio mode for cache command

    //config sram cache r/w command
    switch (psram_cache_mode) {
        case PSRAM_CACHE_F80M_S80M: //in this mode , no delay is needed
            SET_PERI_REG_BITS(SPI_SRAM_DWR_CMD_REG(0), SPI_CACHE_SRAM_USR_WR_CMD_BITLEN, 7,
                    SPI_CACHE_SRAM_USR_WR_CMD_BITLEN_S);
            SET_PERI_REG_BITS(SPI_SRAM_DWR_CMD_REG(0), SPI_CACHE_SRAM_USR_WR_CMD_VALUE, 0x38,
                    SPI_CACHE_SRAM_USR_WR_CMD_VALUE_S); //0x38
            SET_PERI_REG_BITS(SPI_SRAM_DRD_CMD_REG(0), SPI_CACHE_SRAM_USR_RD_CMD_BITLEN_V, 7,
                    SPI_CACHE_SRAM_USR_RD_CMD_BITLEN_S);
            SET_PERI_REG_BITS(SPI_SRAM_DRD_CMD_REG(0), SPI_CACHE_SRAM_USR_RD_CMD_VALUE_V, 0x0b,
                    SPI_CACHE_SRAM_USR_RD_CMD_VALUE_S); //0x0b
            break;
        case PSRAM_CACHE_F80M_S40M: //is sram is @40M, need 2 cycles of delay
        case PSRAM_CACHE_F40M_S40M:
        default:
            SET_PERI_REG_BITS(SPI_SRAM_DRD_CMD_REG(0), SPI_CACHE_SRAM_USR_RD_CMD_BITLEN_V, 15,
                    SPI_CACHE_SRAM_USR_RD_CMD_BITLEN_S); //read command length, 2 bytes(1byte for delay),sending in qio mode in cache
            SET_PERI_REG_BITS(SPI_SRAM_DRD_CMD_REG(0), SPI_CACHE_SRAM_USR_RD_CMD_VALUE_V, 0x0b00,
                    SPI_CACHE_SRAM_USR_RD_CMD_VALUE_S); //0x0b, read command value,(0x00 for delay,0x0b for cmd)
            SET_PERI_REG_BITS(SPI_SRAM_DWR_CMD_REG(0), SPI_CACHE_SRAM_USR_WR_CMD_BITLEN, 15,
                    SPI_CACHE_SRAM_USR_WR_CMD_BITLEN_S); //write command length,2 bytes(1byte for delay,send in qio mode in cache)
            SET_PERI_REG_BITS(SPI_SRAM_DWR_CMD_REG(0), SPI_CACHE_SRAM_USR_WR_CMD_VALUE, 0x3800,
                    SPI_CACHE_SRAM_USR_WR_CMD_VALUE_S); //0x38, write command value,(0x00 for delay)
            break;
    }

    CLEAR_PERI_REG_MASK(DPORT_PRO_CACHE_CTRL_REG, DPORT_PRO_DRAM_HL|DPORT_PRO_DRAM_SPLIT);
    CLEAR_PERI_REG_MASK(DPORT_APP_CACHE_CTRL_REG, DPORT_APP_DRAM_HL|DPORT_APP_DRAM_SPLIT);
    if (vaddrmode == PSRAM_VADDR_MODE_LOWHIGH) {
        SET_PERI_REG_MASK(DPORT_PRO_CACHE_CTRL_REG, DPORT_PRO_DRAM_HL);
        SET_PERI_REG_MASK(DPORT_APP_CACHE_CTRL_REG, DPORT_APP_DRAM_HL);
    } else if (vaddrmode == PSRAM_VADDR_MODE_EVENODD) {
        SET_PERI_REG_MASK(DPORT_PRO_CACHE_CTRL_REG, DPORT_PRO_DRAM_SPLIT);
        SET_PERI_REG_MASK(DPORT_APP_CACHE_CTRL_REG, DPORT_APP_DRAM_SPLIT);
    }

    CLEAR_PERI_REG_MASK(DPORT_PRO_CACHE_CTRL1_REG, DPORT_PRO_CACHE_MASK_DRAM1|DPORT_PRO_CACHE_MASK_OPSDRAM); //use Dram1 to visit ext sram.
    //cache page mode : 1 -->16k  4 -->2k  0-->32k,(accord with the settings in cache_sram_mmu_set)
    SET_PERI_REG_BITS(DPORT_PRO_CACHE_CTRL1_REG, DPORT_PRO_CMMU_SRAM_PAGE_MODE, 0, DPORT_PRO_CMMU_SRAM_PAGE_MODE_S);
    CLEAR_PERI_REG_MASK(DPORT_APP_CACHE_CTRL1_REG, DPORT_APP_CACHE_MASK_DRAM1|DPORT_APP_CACHE_MASK_OPSDRAM); //use Dram1 to visit ext sram.
    //cache page mode : 1 -->16k  4 -->2k  0-->32k,(accord with the settings in cache_sram_mmu_set)
    SET_PERI_REG_BITS(DPORT_APP_CACHE_CTRL1_REG, DPORT_APP_CMMU_SRAM_PAGE_MODE, 0, DPORT_APP_CMMU_SRAM_PAGE_MODE_S);
    CLEAR_PERI_REG_MASK(SPI_PIN_REG(0), SPI_CS1_DIS_M); //ENABLE SPI0 CS1 TO PSRAM(CS0--FLASH; CS1--SRAM)
}

/*
 Before flushing the cache, if psram is enabled, we need to write back the data in the cache to the psram first,
 otherwise it will get lost. For now, we just read 64/128K of random PSRAM memory to do this. Yes, we should be
 able to optimize this. Later.
*/
void IRAM_ATTR esp_psram_writeback_cache() 
{
	int x;
	volatile int i=0;
	volatile uint8_t *psram=(volatile uint8_t*)0x3F800000;
	int cacheWasDisabled=0;

	//We need cache enabled for this to work. Re-enable it if needed; make sure we 
	//disable it again on exit as well.
	if (REG_GET_BIT(DPORT_PRO_CACHE_CTRL_REG, DPORT_PRO_CACHE_ENABLE)==0) {
			cacheWasDisabled|=(1<<0);
			SET_PERI_REG_BITS(DPORT_PRO_CACHE_CTRL_REG, 1, 1, DPORT_PRO_CACHE_ENABLE_S);
	}
#ifndef CONFIG_FREERTOS_UNICORE
	if (REG_GET_BIT(DPORT_APP_CACHE_CTRL_REG, DPORT_APP_CACHE_ENABLE)==0) {
		cacheWasDisabled|=(1<<1);
		SET_PERI_REG_BITS(DPORT_APP_CACHE_CTRL_REG, 1, 1, DPORT_APP_CACHE_ENABLE_S);
	}
#endif

#if CONFIG_FREERTOS_UNICORE
	for (x=0; x<1024*64; x+=32) {
		i+=psram[x];
	}
#else
	for (x=0; x<1024*64; x+=32) {
		i+=psram[x];
		i+=psram[x+(1024*1024*2)+(1024*64)]; //address picked to also clear cache of app cpu in low/high mode
	}
#endif

	if (cacheWasDisabled&(1<<0)) SET_PERI_REG_BITS(DPORT_PRO_CACHE_CTRL_REG, 1, 0, DPORT_PRO_CACHE_ENABLE_S);
#ifndef CONFIG_FREERTOS_UNICORE
	if (cacheWasDisabled&(1<<1)) SET_PERI_REG_BITS(DPORT_APP_CACHE_CTRL_REG, 1, 0, DPORT_APP_CACHE_ENABLE_S);
#endif
}