Using hsm stop in hsm wait loop causes secondary harts to be stuck
forever in OpenSBI on RISC-V platforms where HSM hart hotplug is
available and all harts come-up at the same time during system
power-on.
For example, lets say we have two harts A and B on a RISC-V platform
with HSM hart hotplug which come-up at the same time during system
power-on. The hart A enters OpenSBI before hart B hence it becomes
the primary (or cold-boot) hart whereas hart B becomes the secondary
(or warm-boot) hart. The hart A follows the OpenSBI cold-boot path
and registers hsm device before hart B enters OpenSBI. The hart B
eventually enters OpenSBI and follows the OpenSBI warm-boot path
so it will increment it's own entry_count before entering hsm wait
loop where it sees hsm device and stops itself. Later as part of
the Linux boot-up sequence, hart A issues SBI HSM start call to
bring-up hart B but OpenSBI sees entry_count != init_count for
hart B in sbi_hsm_hart_start() hence hsm_device_hart_start() is
not called for hart B resulting in hart B stuck forever in OpenSBI.
To fix the above issue, revert entry_count before doing hsm stop
in hsm wait loop.
Fixes: d844deadec ("lib: sbi: Use hsm stop for hsm wait")
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Nick Hu <nick.hu@sifive.com>
Link: https://lore.kernel.org/r/20250527124821.2113467-1-apatel@ventanamicro.com
Signed-off-by: Anup Patel <anup@brainfault.org>
All callers already have the hartindex available, so this removes a
hartid to hartindex conversion.
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
We introduce sbi_entry_count() function which counts the number
of times a HART enters OpenSBI via cold-boot or warm-boot path.
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
We add sbi_init_count() API which provides number of times a
given HART completed init sequence (warmboot/coldboot).
This will be very useful in debugging. With upcoming SBI HSM
extension, it will also help in implementing one-time init
code for each HART.
Signed-off-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
This patch adds initial implementation of sbi_exit() API which
can be used to perform OpenSBI exit sequence for current HART.
The sbi_exit() implementation will be further extended by
subsequent patches.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
This patch updates copyright header in all files as follows:
1. Makes "SPDX-License-Identifier: BSD-2-Clause" as first line
2. Change copyright year to 2019 for Western Digital
Signed-off-by: Anup Patel <anup.patel@wdc.com>
