[RFC PATCH 01/21] RISC-V: Detect the Ssqosid extension

[Drew Fustini]

Ssqosid is the Supervisor QoS ID extension defined in the RISC-V CBQRI
(Capacity and Bandwidth QoS Register Interface) specification.

Link: https://github.com/riscv-non-isa/riscv-cbqri/blob/main/riscv-cbqri.pdf
Signed-off-by: Kornel Dulęba <mindal@xxxxxxxxxxxx>
[dfustini: rebase from v6.0 to v6.3]
Signed-off-by: Drew Fustini <dfustini@xxxxxxxxxxxx>
---
Note:
- A version of this patch rebased on riscv/for-next was already
  submitted as an RFC to linux-riscv [1] with Message-ID:
    20230410043646.3138446-1-dfustini@xxxxxxxxxxxx
- This patch is included in this RFC series so as to provide a cohesive
  demonstration in one series.

[1] https://lore.kernel.org/lkml/20230410043646.3138446-1-dfustini@xxxxxxxxxxxx/

 arch/riscv/include/asm/hwcap.h | 2 ++
 arch/riscv/kernel/cpu.c        | 1 +
 arch/riscv/kernel/cpufeature.c | 1 +
 3 files changed, 4 insertions(+)

diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h
index e3021b2590de..255c5c4d0a24 100644
--- a/arch/riscv/include/asm/hwcap.h
+++ b/arch/riscv/include/asm/hwcap.h
@@ -42,6 +42,8 @@
 #define RISCV_ISA_EXT_ZBB		30
 #define RISCV_ISA_EXT_ZICBOM		31
 #define RISCV_ISA_EXT_ZIHINTPAUSE	32
+#define RISCV_ISA_EXT_SSQOSID		35
+
 
 #define RISCV_ISA_EXT_MAX		64
 #define RISCV_ISA_EXT_NAME_LEN_MAX	32
diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
index 8400f0cc9704..d1441872f173 100644
--- a/arch/riscv/kernel/cpu.c
+++ b/arch/riscv/kernel/cpu.c
@@ -189,6 +189,7 @@ static struct riscv_isa_ext_data isa_ext_arr[] = {
 	__RISCV_ISA_EXT_DATA(zihintpause, RISCV_ISA_EXT_ZIHINTPAUSE),
 	__RISCV_ISA_EXT_DATA(zbb, RISCV_ISA_EXT_ZBB),
 	__RISCV_ISA_EXT_DATA(sscofpmf, RISCV_ISA_EXT_SSCOFPMF),
+	__RISCV_ISA_EXT_DATA(ssqosid, RISCV_ISA_EXT_SSQOSID),
 	__RISCV_ISA_EXT_DATA(sstc, RISCV_ISA_EXT_SSTC),
 	__RISCV_ISA_EXT_DATA(svinval, RISCV_ISA_EXT_SVINVAL),
 	__RISCV_ISA_EXT_DATA(svpbmt, RISCV_ISA_EXT_SVPBMT),
diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
index 59d58ee0f68d..80317d2d3975 100644
--- a/arch/riscv/kernel/cpufeature.c
+++ b/arch/riscv/kernel/cpufeature.c
@@ -222,6 +222,7 @@ void __init riscv_fill_hwcap(void)
 			} else {
 				/* sorted alphabetically */
 				SET_ISA_EXT_MAP("sscofpmf", RISCV_ISA_EXT_SSCOFPMF);
+				SET_ISA_EXT_MAP("ssqosid", RISCV_ISA_EXT_SSQOSID);
 				SET_ISA_EXT_MAP("sstc", RISCV_ISA_EXT_SSTC);
 				SET_ISA_EXT_MAP("svinval", RISCV_ISA_EXT_SVINVAL);
 				SET_ISA_EXT_MAP("svpbmt", RISCV_ISA_EXT_SVPBMT);
-- 
2.34.1