Hitachi HS7729PCI

Overview

RedBoot uses the COM1 and COM2 serial ports (and the debug port on the motherboard). The default serial port settings are 38400,8,N,1. Ethernet is also supported using a D-Link DFE-530TX PCI plugin card.

Management of onboard flash is also supported. Two basic RedBoot configurations are supported:

Initial Installation Method

A copy of the ROM startup version of RedBoot must be programmed into the two EPROMs. Two files with a split version of the ROM image is provided: it is also possible to recreate these from the redboot.bin file, but requires the split_word.c program in hal/sh/hs7729pci/VERSION/misc to be built and executed with the redboot.bin filename as sole argument.

After doing this it is advised that another ROM version of RedBoot is programmed into the flash, and that copy be used for booting the board. This allows for software programmed updates of RedBoot instead of having to reprogram the EPROMs.

  1. Program the EPROMs with RedBoot. The .lo image should go in socket M1 and the .hi image in socket M2.

  2. Set switch SW1-6 to ON [boot from EPROM]

  3. Follow the instructions under Flash management for updating the flash copy of RedBoot, but use
    -f 0x80400000
    due to setting of the SW1-6 switch.

  4. Set switch SW1-6 to OFF [boot from flash] and reboot the board. You should now see the RedBoot banner. At this time you may want to issue the command
    fis init
    to initialize the flash table with the correct addresses.

Flash management

Special RedBoot Commands

The exec command which allows the loading and execution of Linux kernels is supported for this board (see the Section called Executing Programs from RedBoot in Chapter 2). The exec parameters used for the HS7729PCI are:

-b <addr>

Parameter block address. This is normally the first page of the kernel image and defaults to 0x8c101000

-i <addr>

Start address of initrd image

-j <size>

Size of initrd image

-c "args"

Kernel arguments string

-m <flags>

Mount rdonly flags. If set to a non-zero value the root partition will be mounted read-only.

-f <flags>

RAM disk flags. Should normally be 0x4000

-r <device number>

Root device specification. /dev/ram is 0x0101

-l <type>

Loader type

Finally the kernel entry address can be specified as an optional argument. The default is 0x8c102000

On the HS7729PCI, Linux expects to be loaded at address 0x8c101000 with the entry point at 0x8c102000. This is configurable in the kernel using the CONFIG_MEMORY_START option.

Memory Maps

RedBoot sets up the following memory map on the HS7729PCI board.
Physical Address Range  Description
----------------------- -----------
0x80000000 - 0x803fffff Flash (MBM29LV160)
0x80400000 - 0x807fffff EPROM (M27C800)
0x82000000 - 0x82ffffff SRAM
0x89000000 - 0x89ffffff SRAM
0x8c000000 - 0x8fffffff SDRAM
0xa8000000 - 0xa800ffff SuperIO (FDC37C935A)
0xa8400000 - 0xa87fffff USB function (ML60851C)
0xa8800000 - 0xa8bfffff USB host (SL11HT)
0xa8c00000 - 0xa8c3ffff Switches
0xa8c40000 - 0xa8c7ffff LEDs
0xa8c80000 - 0xa8cfffff Interrupt controller
0xb0000000 - 0xb3ffffff PCI (SD0001)
0xb8000000 - 0xbbffffff PCMCIA (MaruBun)

Resource Usage

The flash based RedBoot image occupies flash addresses 0x80000000 - 0x8001ffff. RedBoot also reserves RAM (0x8c000000 - 0x8c01ffff) for RedBoot runtime uses. RAM based RedBoot configurations are designed to run from RAM at physical addresses 0x8c020000 - 0x8c07ffff. RAM physical addresses from 0x8c080000 to the end of RAM are available for general use, such as a temporary scratchpad for downloaded images, before they are written to flash.

Rebuilding RedBoot

The instructions in Chapter 3 should be followed. The values for TARGET, ARCH_DIR and PLATFORM_DIR on this platform are “hs7729pci”, “sh” and “hs7729pci” respectively. Note that the configuration export files supplied in the hal/sh/hs7729pci/VERSION/misc directory in the RedBoot source tree should be used.