diff mbox series

[v3,2/4] RISC-V: configure and turn on vector extension from command line

Message ID 20200103033347.20909-3-zhiwei_liu@c-sky.com (mailing list archive)
State New, archived
Headers show
Series RISC-V: support vector extension part 1 | expand

Commit Message

LIU Zhiwei Jan. 3, 2020, 3:33 a.m. UTC 
Vector extension is default on only for "any" cpu. It can be turned
on by command line "-cpu rv64,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.
Thest properties and cpu can be specified with other values.

Signed-off-by: LIU Zhiwei <zhiwei_liu@c-sky.com>
---
 target/riscv/cpu.c | 42 ++++++++++++++++++++++++++++++++++++++++--
 target/riscv/cpu.h |  8 ++++++++
 2 files changed, 48 insertions(+), 2 deletions(-)

Comments

Richard Henderson Jan. 3, 2020, 11:08 p.m. UTC | #1 
On 1/3/20 2:33 PM, LIU Zhiwei wrote:
> +        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) {
> +                error_setg(errp,
> +                       "Vector extension VLEN must <= %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;
> +            }

Missing maximum on elen.
Missing minimum on vlen, which, as I discussed earlier, should be 128 to avoid
asserts in tcg-op-gvec.c.


>  #define PRIV_VERSION_1_10_0 0x00011000
>  #define PRIV_VERSION_1_11_0 0x00011100
>  
> +#define VEXT_VERSION_0_07_1 0x00000071

To match the other version number formats, surely this should be 0x00000701.


r~
Jim Wilson Jan. 6, 2020, 9:48 p.m. UTC | #2 
On 1/2/20 7:33 PM, LIU Zhiwei wrote:
> +            if (cpu->cfg.vlen > RV_VLEN_MAX) {
> +                error_setg(errp,
> +                       "Vector extension VLEN must <= %d", RV_VLEN_MAX);
> +                return;

There is no architectural maximum for VLEN.  This is simply an 
implementation choice so you can use static arrays instead of malloc.  I 
think this error should be reworded to something like "Vector extension 
implementation only supports VLEN <= %d."

The other errors here are for architecture requirements and are OK.

Jim
LIU Zhiwei Jan. 7, 2020, 1:42 a.m. UTC | #3 
On 2020/1/7 5:48, Jim Wilson wrote:
> On 1/2/20 7:33 PM, LIU Zhiwei wrote:
>> +            if (cpu->cfg.vlen > RV_VLEN_MAX) {
>> +                error_setg(errp,
>> +                       "Vector extension VLEN must <= %d", 
>> RV_VLEN_MAX);
>> +                return;
>
> There is no architectural maximum for VLEN.  This is simply an 
> implementation choice so you can use static arrays instead of malloc.  
> I think this error should be reworded to something like "Vector 
> extension implementation only supports VLEN <= %d."
Thanks. It's good to reduce ambiguous.
Zhiwei
> The other errors here are for architecture requirements and are OK.
>
> Jim
diff mbox series

Patch

diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index f8d07bd20a..c2370a0a57 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -94,6 +94,11 @@  static void set_priv_version(CPURISCVState *env, int priv_ver)
     env->priv_ver = priv_ver;
 }
 
+static void set_vext_version(CPURISCVState *env, int vext_ver)
+{
+    env->vext_ver = vext_ver;
+}
+
 static void set_feature(CPURISCVState *env, int feature)
 {
     env->features |= (1ULL << feature);
@@ -109,7 +114,7 @@  static void set_resetvec(CPURISCVState *env, int resetvec)
 static void riscv_any_cpu_init(Object *obj)
 {
     CPURISCVState *env = &RISCV_CPU(obj)->env;
-    set_misa(env, RVXLEN | RVI | RVM | RVA | RVF | RVD | RVC | RVU);
+    set_misa(env, RVXLEN | RVI | RVM | RVA | RVF | RVD | RVC | RVU | RVV);
     set_priv_version(env, PRIV_VERSION_1_11_0);
     set_resetvec(env, DEFAULT_RSTVEC);
 }
@@ -317,6 +322,7 @@  static void riscv_cpu_realize(DeviceState *dev, Error **errp)
     CPURISCVState *env = &cpu->env;
     RISCVCPUClass *mcc = RISCV_CPU_GET_CLASS(dev);
     int priv_version = PRIV_VERSION_1_11_0;
+    int vext_version = VEXT_VERSION_0_07_1;
     target_ulong target_misa = 0;
     Error *local_err = NULL;
 
@@ -340,8 +346,18 @@  static void riscv_cpu_realize(DeviceState *dev, Error **errp)
             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;
+        }
+    }
     set_priv_version(env, priv_version);
+    set_vext_version(env, vext_version);
     set_resetvec(env, DEFAULT_RSTVEC);
 
     if (cpu->cfg.mmu) {
@@ -406,6 +422,24 @@  static void riscv_cpu_realize(DeviceState *dev, Error **errp)
         if (cpu->cfg.ext_u) {
             target_misa |= RVU;
         }
+        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) {
+                error_setg(errp,
+                       "Vector extension VLEN must <= %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;
+            }
+        }
 
         set_misa(env, RVXLEN | target_misa);
     }
@@ -441,10 +475,14 @@  static Property riscv_cpu_properties[] = {
     DEFINE_PROP_BOOL("c", RISCVCPU, cfg.ext_c, true),
     DEFINE_PROP_BOOL("s", RISCVCPU, cfg.ext_s, true),
     DEFINE_PROP_BOOL("u", RISCVCPU, cfg.ext_u, true),
+    DEFINE_PROP_BOOL("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 af66674461..d0b106583a 100644
--- a/target/riscv/cpu.h
+++ b/target/riscv/cpu.h
@@ -64,6 +64,7 @@ 
 #define RVA RV('A')
 #define RVF RV('F')
 #define RVD RV('D')
+#define RVV RV('V')
 #define RVC RV('C')
 #define RVS RV('S')
 #define RVU RV('U')
@@ -82,6 +83,8 @@  enum {
 #define PRIV_VERSION_1_10_0 0x00011000
 #define PRIV_VERSION_1_11_0 0x00011100
 
+#define VEXT_VERSION_0_07_1 0x00000071
+
 #define TRANSLATE_PMP_FAIL 2
 #define TRANSLATE_FAIL 1
 #define TRANSLATE_SUCCESS 0
@@ -119,6 +122,7 @@  struct CPURISCVState {
     target_ulong badaddr;
 
     target_ulong priv_ver;
+    target_ulong vext_ver;
     target_ulong misa;
     target_ulong misa_mask;
 
@@ -236,12 +240,16 @@  typedef struct RISCVCPU {
         bool ext_c;
         bool ext_s;
         bool ext_u;
+        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;
         bool pmp;
     } cfg;