[PATCH v2 0/3] lib: sbi: Fix Smrnmi resume init and optional platform callback

[Evgeny Voevodin]

Patch 1/3, two things.

- I'd put the sbi_smrnmi_hart_init() call in the beginning of
  sbi_hart_reinit() to initialize trap handlers early.

- Worth noting that after this change we have sbi_smrnmi_hart_init()
  called twice on cold boot, one from hart_detect_features() and another
  from sbi_hart_reinit() at the end of sbi_hart_init(). As long as
  platform's smrnmi context initialization allows it, this doesn't bite.
  Please mention it where smrnmi_handlers_init is declared in
  sbi_platform.h, so a platform knows the callback can be called more
  than once on the same HART.

Patch 3/3, two things.

- Global variable is racy because every hart writes smrnmi_init_mode and
  boot hart reads it. How about make the banner stateless:

      const struct sbi_platform *plat = sbi_platform_thishart_ptr();

      if (sbi_hart_has_extension(scratch, SBI_HART_EXT_SMRNMI))
              sbi_printf("Boot HART Smrnmi Init       : %s\n",
                         plat && sbi_platform_ops(plat)->smrnmi_handlers_init ?
                         "Platform" : "Default");

  also this is lightweight and clearly describes the status. Then
  smrnmi_init_mode, the enum and sbi_hart_get_smrnmi_status_str() are
  not needed.

- Also, I didn't see a platform flag to indicate that it doesn't need to
  initialize Smrnmi handlers so that boot code can proceed without
  smrnmi_handlers installed. Did you plan to add it?

  Thanks,
  Evgeny