On Mon, 18 Jul 2022 at 16:00, Tom Rini <tr...@konsulko.com> wrote: > On Mon, Jul 18, 2022 at 10:31:56AM -0500, Jassi Brar wrote:
> > > > > > > > > > > > > > + > > > > > > > > +#define PLAT_METADATA_OFFSET 0x510000 > > > > > > > > +#define PLAT_METADATA_SIZE (sizeof(struct devbox_metadata)) > > > > > > > > + > > > > > > > > +struct __packed devbox_metadata { > > > > > > > > + u32 boot_index; > > > > > > > > + u32 boot_count; > > > > > > > > > > > > > > There is the whole bootcount infrastructure for this. I think it > > > > > > > would be much > > > > > > > better to use that framework instead of creating parallel one. > > > > > > > > > > > > > Yes, this goes too. > > > > > > > > > > Is bootcount really suited for this case? > > > > > AFAIK bootcount either requires device specific registers (which won't > > > > > reset on reboots), or an environment you can write data to. > > > > > But what if a user wants to disable writing the env variables and the > > > > > device doesn't have a set of registers we can use? > > > > > > > > > Maybe it should be moved in 'struct fwu_mdata' ? > > > > > > I was mostly thinking on moving this count as another 'bootcount' > > > method. So in case the user has disabled writing evn variables but he > > > is booting with EFI he can use that. > > > > Sorry, not sure I understand.... IIUIC there has to be some persistent > > storage. > > No, there just has to be "somewhere" to do the counting. We've got a > DDR backed driver, for example. So yes, I think we should try and use > the bootcount framework here. > OK, for platforms that can preserve ram across reboot, using non-persistent storage can work. My platform neither preserves ram, nor has any warmreset-proof registers. So I have to choose between saving the bootcount in efi-env or in vendor specific structure next to the metadata. I prefer metadata because it is common to all stages of boot. Any corrections to this approach? Thanks