pointer masking: Let menvcfg.PMM be WARL if with Smnpm

Author: YenHaoChen

riscv/csrs.cc

@@ -975,7 +975,12 @@ envcfg_csr_t::envcfg_csr_t(processor_t* const proc, const reg_t addr, const reg_
 
 bool envcfg_csr_t::unlogged_write(const reg_t val) noexcept {
   const reg_t cbie_reserved = 2; // Reserved value of xenvcfg.CBIE
-  const reg_t adjusted_val = get_field(val, MENVCFG_CBIE) != cbie_reserved ? val : set_field(val, MENVCFG_CBIE, 0);
+  reg_t adjusted_val = get_field(val, MENVCFG_CBIE) != cbie_reserved ? val : set_field(val, MENVCFG_CBIE, 0);
+
+  const reg_t pmm_reserved = 1; // Reserved value of xseccfg.PMM
+  const reg_t pmm = get_field(adjusted_val, MENVCFG_PMM);
+  adjusted_val = set_field(adjusted_val, MENVCFG_PMM, pmm != pmm_reserved ? pmm : 0);
+
   return masked_csr_t::unlogged_write(adjusted_val);
 }
 

riscv/processor.cc

@@ -388,6 +388,7 @@ void state_t::reset(processor_t* const proc, reg_t max_isa)
   if (proc->extension_enabled_const('U')) {
     const reg_t menvcfg_mask = (proc->extension_enabled(EXT_ZICBOM) ? MENVCFG_CBCFE | MENVCFG_CBIE : 0) |
                               (proc->extension_enabled(EXT_ZICBOZ) ? MENVCFG_CBZE : 0) |
+                              (proc->extension_enabled(EXT_SMNPM) ? MENVCFG_PMM : 0) |
                               (proc->extension_enabled(EXT_SVADU) ? MENVCFG_ADUE: 0) |
                               (proc->extension_enabled(EXT_SVPBMT) ? MENVCFG_PBMTE : 0) |
                               (proc->extension_enabled(EXT_SSTC) ? MENVCFG_STCE : 0) |