/zephyr-spi-flash-en25-driver

Primary LanguageC

Zepyhr SPi flash driver for EN25QH32B-104HIP2C flash chip

This repository contains driver and tests for interfacing with EN25QH32B-104HIP2C via the zephyr flash API.

This drive is compatible with the following flash chips:

  • EN25QH32B with JEDEC id [1c 70 16]
  • IS25WP032D with JEDEC id [9D 70 16]
  • W25Q32JVSSIQ with JEDEC id [EF 40 16]
  • AT25SL321 with JEDEC id [1F 42 16]

Setup

  1. To your west.yml add the irnas remote to the remotes section:

    - name: irnas
  url-base: https://github.com/irnas

  2. Then in the projects section add at the bottom:

    - name: zephyr-spi-flash-en25-driver
  repo-path: zephyr-spi-flash-en25-driver
  path: irnas/zephyr-spi-flash-en25-driver
  remote: irnas
  revision: <revision>

  3. Add the flash DTS entry to your board definition or overlay file. For example:


&spi0 {
   // ...

    en25qh32b: en25qh32b@0 {
        reg = <0>;
        label = "EN25QH32B";
        status = "okay";
        compatible = "mxicy,en25";

        jedec-id = [ 1c 70 16  ];  // EN25
        size = <(4194304 * 8)>;

        write-sector-size = <256>;
        erase-full-block-size = <65536>;
        erase-half-block-size = <32768>;
        erase-sector-size = <4096>;

        spi-max-frequency = <4000000>;

        enter-dpd-delay = <30>;
        exit-dpd-delay = <30>;

        wp-gpios = <&gpio0 22 0>;
        hold-gpios = <&gpio0 23 0>;
    };
};

External mutex

This driver can be used on multiple MCUs to use the same SPI flash peripheral. To achieve this, a GPIO line must be shared between the MCUs, the flash chip must be the only peripheral on this SPI bus and both MCUs must be using this driver to communicate with the external flash. To enable this feature, add ext-mutex-gpios, ext-mutex-role and spi-clk-gpios to the DTS flash definition.

For two MCUs, set one ext-mutex-role to master and one to slave. For more than 2 MCUs, set one to master and all others to slave.

For example:


&spi0 {
   // ...

    en25qh32b: en25qh32b@0 {
        // ...

        ext-mutex-gpios =  <&gpio0 24 (GPIO_ACTIVE_HIGH | GPIO_PULL_DOWN)>;
        ext-mutex-role = "slave";
        spi-clk-gpios = <&gpio0 28 0>;  // must be same as the pinctrl entry of the enclosing spi peripheral
    };
};

The setting SPI_FLASH_EN25_EXTERNAL_MUTEX_TIMEOUT can also be configured to specify the amount of time a MCU is willing to wait for the SPI lock to be released.

Tests

  1. Navigate to ./tests/flash_read_write
  2. Build for one of the boards with supplied overlay, of make your own. Use west build -b nrf52840dk_nrf52840 for example.
  3. flash with west flash