These variables act like loadaddr, but for a device tree image. Defining
them in the environment allows boot scripts to be identical on Tegra20 and
Tegra30, which have different memory base addresses, and hence need
different values for these variables.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
Instead of initializing USB as soon as bootcmd is executed, defer it
until the first boot device that (potentially in the case of network)
uses USB is scanned. This avoids initializing USB when booting from MMC,
so speeds that up.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
Place the list of searched boot devices, file-system types, boot file
locations/prefixes, and boot script names into variables. This allows
the user to override them directly (e.g. to change boot order, or select
the specific values they use) without having to edit the main bootcmd
and script_boot variables.
The default boot order is changed from USB, MMC, DHCP to MMC, USB, DHCP.
This speeds up the typical MMC boot case. People who want USB boot can
now edit variable boot_targets appropriately.
Also, reformat BOOTCMDS_COMMON to fit within 80 columns.
Potential future enhancements might be:
* Allow boards to specify which of bootcmd_mmc0/... should be defined,
based on the HW they contain.
* Allow boards to influence the order that the boot targets are added
into the boot_targets variable.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
This implements a useful bootcmd for Tegra. The boot order is:
* If USB enabled, USB storage
* Internal MMC (SD card or eMMC)
* If networking is enabled, BOOTP/TFTP
When booting from USB or MMC, the boot script is assumed to be in
partition 1 (although this may be overridden via the rootpart variable),
both ext2 and FAT filesystems are supported, the boot script may exist
in either / or /boot, and the boot script may be named boot.scr.uimg or
boot.scr.
When booting over the network, it is assumed that boot.scr.uimg exists
on the TFTP server. There is less flexibility here since those setting
up network booting are expected to need less hand-holding.
In all cases, it is expected that the initial file loaded is a U-Boot
image containing a script that will load the kernel, load any required
initrd, load any required DTB, and finally bootm the kernel.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
