target/riscv: configure and turn on vector extension from command line

Vector extension is default off. The only way to use vector extension is
1. use cpu rv32 or rv64
2. turn on it by command line
   "-cpu rv64,x-v=true,vlen=128,elen=64,vext_spec=v0.7.1".

vlen is the vector register length, default value is 128 bit.
elen is the max operator size in bits, default value is 64 bit.
vext_spec is the vector specification version, default value is v0.7.1.
These properties can be specified with other values.

Signed-off-by: LIU Zhiwei <zhiwei_liu@c-sky.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200701152549.1218-62-zhiwei_liu@c-sky.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index d525cfb6876e1cd28077cf6a7c25bc5d6aaf2bd0..228b9bdb5d600911c7fd1a7435578746de44b030 100644 (file)
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -430,6 +430,45 @@ static void riscv_cpu_realize(DeviceState *dev, Error **errp)
         if (cpu->cfg.ext_h) {
             target_misa |= RVH;
         }
+        if (cpu->cfg.ext_v) {
+            target_misa |= RVV;
+            if (!is_power_of_2(cpu->cfg.vlen)) {
+                error_setg(errp,
+                        "Vector extension VLEN must be power of 2");
+                return;
+            }
+            if (cpu->cfg.vlen > RV_VLEN_MAX || cpu->cfg.vlen < 128) {
+                error_setg(errp,
+                        "Vector extension implementation only supports VLEN "
+                        "in the range [128, %d]", RV_VLEN_MAX);
+                return;
+            }
+            if (!is_power_of_2(cpu->cfg.elen)) {
+                error_setg(errp,
+                        "Vector extension ELEN must be power of 2");
+                return;
+            }
+            if (cpu->cfg.elen > 64 || cpu->cfg.vlen < 8) {
+                error_setg(errp,
+                        "Vector extension implementation only supports ELEN "
+                        "in the range [8, 64]");
+                return;
+            }
+            if (cpu->cfg.vext_spec) {
+                if (!g_strcmp0(cpu->cfg.vext_spec, "v0.7.1")) {
+                    vext_version = VEXT_VERSION_0_07_1;
+                } else {
+                    error_setg(errp,
+                           "Unsupported vector spec version '%s'",
+                           cpu->cfg.vext_spec);
+                    return;
+                }
+            } else {
+                qemu_log("vector verison is not specified, "
+                        "use the default value v0.7.1\n");
+            }
+            set_vext_version(env, vext_version);
+        }
 
         set_misa(env, RVXLEN | target_misa);
     }
@@ -469,10 +508,14 @@ static Property riscv_cpu_properties[] = {
     DEFINE_PROP_BOOL("u", RISCVCPU, cfg.ext_u, true),
     /* This is experimental so mark with 'x-' */
     DEFINE_PROP_BOOL("x-h", RISCVCPU, cfg.ext_h, false),
+    DEFINE_PROP_BOOL("x-v", RISCVCPU, cfg.ext_v, false),
     DEFINE_PROP_BOOL("Counters", RISCVCPU, cfg.ext_counters, true),
     DEFINE_PROP_BOOL("Zifencei", RISCVCPU, cfg.ext_ifencei, true),
     DEFINE_PROP_BOOL("Zicsr", RISCVCPU, cfg.ext_icsr, true),
     DEFINE_PROP_STRING("priv_spec", RISCVCPU, cfg.priv_spec),
+    DEFINE_PROP_STRING("vext_spec", RISCVCPU, cfg.vext_spec),
+    DEFINE_PROP_UINT16("vlen", RISCVCPU, cfg.vlen, 128),
+    DEFINE_PROP_UINT16("elen", RISCVCPU, cfg.elen, 64),
     DEFINE_PROP_BOOL("mmu", RISCVCPU, cfg.mmu, true),
     DEFINE_PROP_BOOL("pmp", RISCVCPU, cfg.pmp, true),
     DEFINE_PROP_END_OF_LIST(),

diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
index 0ad51c65803934126281cab2d4b10df04a9d800f..eef20ca6e5923b3e3df7da70d962fbfca9738e84 100644 (file)
--- a/target/riscv/cpu.h
+++ b/target/riscv/cpu.h
@@ -92,7 +92,7 @@ typedef struct CPURISCVState CPURISCVState;
 
 #include "pmp.h"
 
-#define RV_VLEN_MAX 512
+#define RV_VLEN_MAX 256
 
 FIELD(VTYPE, VLMUL, 0, 2)
 FIELD(VTYPE, VSEW, 2, 3)
@@ -279,12 +279,14 @@ typedef struct RISCVCPU {
         bool ext_s;
         bool ext_u;
         bool ext_h;
+        bool ext_v;
         bool ext_counters;
         bool ext_ifencei;
         bool ext_icsr;
 
         char *priv_spec;
         char *user_spec;
+        char *vext_spec;
         uint16_t vlen;
         uint16_t elen;
         bool mmu;