Re: [PATCH for-8.1 v4 07/25] target/riscv: move pmp and epmp validations to validate_set_extensions()

[LIU Zhiwei]

On 2023/3/23 6:19, Daniel Henrique Barboza wrote:
In the near future, write_misa() will use a variation of what we have
now as riscv_cpu_validate_set_extensions(). The pmp and epmp validation
will be required in write_misa()

I don't know why pmp and epmp should be checked in write_misa().
As write_misa can't alter the pmp and epmp setting, the check for 
pmp/epmp should only be at cpu object initialization time for one time.

Zhiwei

and it's already required here in
riscv_cpu_realize(), so move it to riscv_cpu_validate_set_extensions().

Signed-off-by: Daniel Henrique Barboza <dbarb...@ventanamicro.com>
---
  target/riscv/cpu.c | 19 +++++++++----------
  1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index 1a298e5e55..7458845fec 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -916,6 +916,15 @@ static void riscv_cpu_validate_set_extensions(RISCVCPU 
*cpu, Error **errp)
      Error *local_err = NULL;
      uint32_t ext = 0;
  
+    if (cpu->cfg.epmp && !cpu->cfg.pmp) {
+        /*
+         * Enhanced PMP should only be available
+         * on harts with PMP support
+         */
+        error_setg(errp, "Invalid configuration: EPMP requires PMP support");
+        return;
+    }
+
      /* Do some ISA extension error checking */
      if (cpu->cfg.ext_g && !(cpu->cfg.ext_i && cpu->cfg.ext_m &&
                              cpu->cfg.ext_a && cpu->cfg.ext_f &&
@@ -1228,16 +1237,6 @@ static void riscv_cpu_realize(DeviceState *dev, Error 
**errp)
          return;
      }
  
-    if (cpu->cfg.epmp && !cpu->cfg.pmp) {
-        /*
-         * Enhanced PMP should only be available
-         * on harts with PMP support
-         */
-        error_setg(errp, "Invalid configuration: EPMP requires PMP support");
-        return;
-    }
-
-
  #ifndef CONFIG_USER_ONLY
      if (cpu->cfg.ext_sstc) {
          riscv_timer_init(cpu);