riscv: Introduce AVAILABLE_HARTS
In SMP all harts will register themself in available_hart
during start up. Then main hart will send IPI to other harts
according to this variables. But this mechanism may not
guarantee that all other harts can jump to next stage.
When main hart is sending IPI to other hart according to
available_harts, but other harts maybe still not finish the
registration. Then the SMP booting will miss some harts finally.
So let it become an option and it will be enabled by default.
Please refer to the discussion:
https://www.mail-archive.com/u-boot@lists.denx.de/msg449997.html
Signed-off-by: Rick Chen <rick@andestech.com>
Reviewed-by: Leo Yu-Chi Liang <ycliang@andestech.com>
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index c042506..32a90b8 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -276,6 +276,13 @@
rely on lock variables (for example hart_lottery and available_harts_lock),
this affects only SPL, other stages should proceed as non-XIP.
+config AVAILABLE_HARTS
+ bool "Send IPI by available harts"
+ default y
+ help
+ By default, IPI sending mechanism will depend on available_harts.
+ If disable this, it will send IPI by CPUs node numbers of device tree.
+
config SHOW_REGS
bool "Show registers on unhandled exception"