The rva22U64 profile, described in:

https://github.com/riscv/riscv-profiles/blob/main/profiles.adoc#rva22-profiles

Contains a set of CPU extensions aimed for 64-bit userspace
applications. Enabling this set to be enabled via a single user flag
makes it convenient to enable a predictable set of features for the CPU,
giving users more predicability when running/testing their workloads.

QEMU implements all possible extensions of this profile. The exception
is Zicbop (Cache-Block Prefetch Operations) that is not available since
QEMU RISC-V does not implement a cache model. For this same reason all
the so called 'synthetic extensions' described in the profile that are
cache related are ignored (Za64rs, Zic64b, Ziccif, Ziccrse, Ziccamoa,
Zicclsm).

An abstraction called RISCVCPUProfile is created to store the profile.
'ext_offsets' contains mandatory extensions that QEMU supports. Same
thing with the 'misa_ext' mask. Optional extensions must be enabled
manually in the command line if desired.

The design here is to use the common target/riscv/cpu.c file to store
the profile declaration and export it to the accelerator files. Each
accelerator is then responsible to expose it (or not) to users and how
to enable the extensions.

Next patches will implement the profile for TCG and KVM.

Signed-off-by: Daniel Henrique Barboza <dbarb...@ventanamicro.com>
---
 target/riscv/cpu.c | 20 ++++++++++++++++++++
 target/riscv/cpu.h | 12 ++++++++++++
 2 files changed, 32 insertions(+)

diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index b3befccf89..a439ff57a4 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -1376,6 +1376,26 @@ Property riscv_cpu_options[] = {
     DEFINE_PROP_END_OF_LIST(),
 };
 
+/* Optional extensions left out: RVV, zfh, zkn, zks */
+static RISCVCPUProfile RVA22U64 = {
+    .name = "rva22u64",
+    .misa_ext = RVM | RVA | RVF | RVD | RVC,
+    .ext_offsets = {
+        CPU_CFG_OFFSET(ext_icsr), CPU_CFG_OFFSET(ext_zihintpause),
+        CPU_CFG_OFFSET(ext_zba), CPU_CFG_OFFSET(ext_zbb),
+        CPU_CFG_OFFSET(ext_zbs), CPU_CFG_OFFSET(ext_zfhmin),
+        CPU_CFG_OFFSET(ext_zkt), CPU_CFG_OFFSET(ext_icntr),
+        CPU_CFG_OFFSET(ext_ihpm), CPU_CFG_OFFSET(ext_icbom),
+        CPU_CFG_OFFSET(ext_icboz),
+
+        RISCV_PROFILE_EXT_LIST_END
+    }
+};
+
+RISCVCPUProfile *riscv_profiles[] = {
+    &RVA22U64, NULL,
+};
+
 static Property riscv_cpu_properties[] = {
     DEFINE_PROP_BOOL("debug", RISCVCPU, cfg.debug, true),
 
diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
index 3f11e69223..216bbbe7cd 100644
--- a/target/riscv/cpu.h
+++ b/target/riscv/cpu.h
@@ -66,6 +66,18 @@ const char *riscv_get_misa_ext_description(uint32_t bit);
 
 #define CPU_CFG_OFFSET(_prop) offsetof(struct RISCVCPUConfig, _prop)
 
+typedef struct riscv_cpu_profile {
+    const char *name;
+    uint32_t misa_ext;
+    bool enabled;
+    bool user_set;
+    const int32_t ext_offsets[];
+} RISCVCPUProfile;
+
+#define RISCV_PROFILE_EXT_LIST_END -1
+
+extern RISCVCPUProfile *riscv_profiles[];
+
 /* Privileged specification version */
 enum {
     PRIV_VERSION_1_10_0 = 0,
-- 
2.41.0


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