Table A-2: Shared Memory Block
Description
Content
Information Type
Indicates which preloader image
(0-3) the boot ROM code loaded
from the flash device. A nonzero
value indicates that there was an
error loading image 0 and the boot
ROM code loaded another image.
Flash image
Common
Indicates the CLKSEL value used
by the boot ROM code. Typically,
this value is the value read from
the
clksel
field of the
bootinfo
register in the
romcodegrp
group in the
system manager. However, if the
PLL fails to lock, the boot ROM
code ignores the
clksel
field
and uses zero to indicate PLL
bypass mode.
CLKSEL value used
Indicates the BOOTSEL value
used by the boot ROM code.
Typically, this value is the value
read from the
bootsel
field of
the
bootinfo
register in the
romcodegrp
group in the
system manager.
BOOTSEL value used
Indicates the number of the last
page read from the flash device.
Last page
Indicates the page size (in bytes)
used by the flash device.
• For NAND flash memory, the
boot ROM code reads this
value from the NAND flash
controller.
• For SPI and quad SPI flash
memory, the boot ROM code
configures the page size
through the quad SPI flash
controller.
• For SD/MMC flash memory,
the boot ROM code configures
the page size through the SD/
MMC flash controller.
Page size
Altera Corporation
Booting and Configuration Introduction
A-9
Shared Memory
cv_5400a
2013.12.30