riscv: clarify meaning of CONFIG_SBI_V02

Describe that CONFIG_SBI_V02=y does not mean SBI specification v0.2
but v0.2 or later.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Rick Chen <rick@andestech.com>

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 4d64e9b..ebc4bef 100644 (file)
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -257,16 +257,16 @@ config SBI_V01
          deprecated in future once legacy M-mode software are no longer in use.
 
 config SBI_V02
-       bool "SBI v0.2 support"
+       bool "SBI v0.2 or later support"
        depends on SBI
        help
-         This config allows kernel to use SBI v0.2 APIs. SBI v0.2 is more
-         scalable and extendable to handle future needs for RISC-V supervisor
-         interfaces. For example, with SBI v0.2 HSM extension, only a single
-         hart need to boot and enter operating system. The booting hart can
-         bring up secondary harts one by one afterwards.
+         The SBI specification introduced the concept of extensions in version
+         v0.2. With this configuration option U-Boot can detect and use SBI
+         extensions. With the HSM extension introduced in SBI 0.2, only a
+         single hart needs to boot and enter the operating system. The booting
+         hart can bring up secondary harts one by one afterwards.
 
-         Choose this option if OpenSBI v0.7 or above release is used together
+         Choose this option if OpenSBI release v0.7 or above is used together
          with U-Boot.
 
 endchoice