Hi all,
After commit aa0eda17cf98 ("spl: opensbi: convert scratch options to config")
it is possible
to specify options for the opensbi, as in struct fw_dynamic_info "options", in
config file.
It is better than hard coded value but still, it is fixed at the compile time.
Can we have this options set at image load time? This would help to enable, for
example,
opensbi debug prints at the runtime. I see an option to do so in FIT image, by
adding
property like "opensbi_options" to the opensbi image node or to the
configuration node.
While bootloader usually flashed on some raw partition and it is not that easy
to
recompile and re-flash it for every run, OS FIT image can be stored on the
partition
formatted with some filesystem so changing FIT image is easy. Also, if it is
only
matter of changing .its file and re-run "mkimage", whole process of changing
opensbi
options became easy.
I see even more value in this for u-boot proper, if we teach it to run in
M-mode, so
for developer boot sequence can be
PBL -> u-boot SPL -> u-boot -> opensbi -> linux
where u-boot will enable network and load FIT image from TFTP; then changing
opensbi flags
will be matter of seconds
Examples, proposed modification marked with "==>":
for opensbi image node:
opensbi {
description = "OpenSBI fw_dynamic Firmware";
data = /incbin/("fw_dynamic.bin");
type = "firmware";
arch = "riscv";
os = "opensbi";
==> opensbi_options =
<2>; // SBI_SCRATCH_DEBUG_PRINTS
compression = "none";
load = <0x8 0x00100000>;
entry = <0x8 0x00100000>;
};
for configuration node:
config-1 {
description = "config-description";
kernel = "linux";
firmware = "opensbi";
==> opensbi_options = <2>; // SBI_SCRATCH_DEBUG_PRINTS
ramdisk = "initrd";
fdt = "fdt-1";
loadables = "linux", "initrd";
};
Comments?
Thanks, Vladimir
