[PATCH v4 3/9] riscv: cpufeature: call match_isa_ext() for single-letter extensions

From: Andy Chiu
Date: Fri Apr 12 2024 - 02:50:10 EST


Single-letter extensions may also imply multiple subextensions. For
example, Vector extension implies zve64d, and zve64d implies zve64f.

Extension parsing for "riscv,isa-extensions" has the ability to resolve
the dependency by calling match_isa_ext(). This patch makes deprecated
parser call the same function for single letter extensions.

Signed-off-by: Andy Chiu <andy.chiu@xxxxxxxxxx>
---
Changelog v3:
- Remove set_bit for single-letter extensions as they are all checked in
match_isa_ext. (Clément)
---
arch/riscv/kernel/cpufeature.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
index d22b12072579..f6f3ece60d69 100644
--- a/arch/riscv/kernel/cpufeature.c
+++ b/arch/riscv/kernel/cpufeature.c
@@ -468,16 +468,15 @@ static void __init riscv_parse_isa_string(unsigned long *this_hwcap, struct risc

if (unlikely(ext_err))
continue;
+
+ for (int i = 0; i < riscv_isa_ext_count; i++)
+ match_isa_ext(&riscv_isa_ext[i], ext, ext_end, isainfo);
+
if (!ext_long) {
int nr = tolower(*ext) - 'a';

- if (riscv_isa_extension_check(nr)) {
+ if (riscv_isa_extension_check(nr))
*this_hwcap |= isa2hwcap[nr];
- set_bit(nr, isainfo->isa);
- }
- } else {
- for (int i = 0; i < riscv_isa_ext_count; i++)
- match_isa_ext(&riscv_isa_ext[i], ext, ext_end, isainfo);
}
}
}

--
2.44.0.rc2