Phytec L-1017e.A3 i.MX 8M Plus, Руководство пользователя

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L-1017e.A3 i.MX 8M Plus BSP Manual
Units: sectors of 1 * 512 = 512 bytes
Device Boot StartCHS EndCHS StartLBA EndLBA Sectors Size
Id Type
/dev/mmcblk2p1 *
128 , 0 , 1 1023 , 3 , 32 16384 140779 124396 60 .7M
c Win95 FAT32 (LBA)
/dev/mmcblk2p2
1023 , 3 , 32 1023 , 3 , 32 141456 14876671 14735216 7194M
83 Linux
Increasing the file system size can be done while it is mounted. An online resizing operation is performed. But you
can also boot the board from an SD card and then resize the file system on the eMMC partition while it is not
mounted. Furthermore, the board has to be rebooted so that the new partition table will be read.
SPI Master
The i.MX 8M Plus controller has a FlexSPI and an ECSPI IP core included. The FlexSPI host controller supports two
SPI channels with up to 4 devices. Each channel supports Single/Dual/Quad/Octal mode data transfer (1/2/4/8
bidirectional data lines). The ECSPI controller supports 3 SPI interfaces with one dedicated chip selected for each
interface. As chip selects should be realized with GPIOs, more than one device on each channel is possible.
SPI NOR flash
phyCORE-i.MX 8M Plus is equipped with a QSPI NOR Flash which connects to the i.MX 8M Plus's FlexSPI interface.
The QSPI NOR Flash is suitable for booting. Please see different sections for
flashing and boot mode setup. Due to
limited space on the SPI NOR Flash, only the bootloader is stored inside. By default, the kernel, device tree, and
rootfs are taken from eMMC.
The Bootloader does detect with the help of the EEPROM Introspection data if an SPI flash is mounted or not. If no
SPI flash is mounted a device tree overlay is applied with the expansion command to disable the SPI flash device
tree node during boot. If no introspection data is available the SPI NOR flash node is always enabled. Find more
information in the device tree overlay
section .
The bootloader also passes the SPI MTD partition table to Linux by fixing up the device tree based on the mtdparts
boot parameter. The default partition layout in the BSP is set to:
mtdparts=30bb0000.spi:3840k(u-boot),128k(env),128k(env_redund),-(none)
This is a bootloader environment variable that is defined here and can be changed during runtime. From
Linux userspace, the NOR Flash partitions are accessible via /dev/mtd<N> devices where <N> is the MTD device
number associated with the NOR flash partition to access. To find the correct MTD device number for a partition,
run on the target:
Count of MTD devices: 4
Present MTD devices: mtd0, mtd1, mtd2, mtd3
Sysfs
interface supported: yes
root @phyboard -pollux-imx8mp- 3 :~# mtdinfo --al
Count of MTD devices: 4
Present MTD devices: mtd0, mtd1, mtd2, mtd3
Sysfs
interface supported: yes