Dave Embedded Systems ARM Cortex-A9 MPCore, Руководство по оборудованию

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A x e l H a r d w a r e M a n u a l v . 1 . 0 . 4
Function Boot signals Available options
of boot ROM
Boot
Configuration4 BOOT_CFG4[6:0]
Specific to selected boot
mode
Boot device selection is specified by BOOT_CFG1[7:3] pins, as
described on the table below:
Boot
device Boot signals
BOOT_CFG[7:3] i.MX6 APRM pin
map reference
EIM 00000 – NOR flash
00001 - OneNAND Table 5.4 (page 352)
SATA 0010X 1 Table 5.5 (page 354)
Serial ROM 0011X 1 Table 5.6 (page 355)
SD/eSD 010XX 1 Table 5.7 (page 356)
MMC/eMMC 011XX 1 Table 5.8 (page 358)
NAND Flash 1XXXX 1 Table 5.9 (page 359)
In order to fully understand how boot works on AXEL platform,
please refer to chapter 8 ("System boot") of the i.MX6 APRM.
5.4.2 Default boot configuration
Default configuration for AXEL module is to boot from SPI NOR
flash, connected to eCSPI5 channel (SS0 chip select) with 3
Byte address mode. This is achieved with the following bit
mapping:
●
BOOT_MODE[1:0] = 10b: Internal mode
●
BOOT_CFG1[7:0] = 00110011b:
●
BOOT_CFG2[7:0] = 11011101b
●
BOOT_CFG3[7:0] = 11001000b
●
BOOT_CFG4[7:0] = 01001100b
The boot code performs hardware initialization, loads
the U-Boot bootloader image (Program Image) from the
chosen boot device and then jumps to an address
1 X: please refer to the device specific BOOT_CFG pin map on the i.MX6 APRM
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