On Sat, Aug 8, 2020 at 6:05 AM Hou Weiying <weiying_...@outlook.com> wrote: > > First, sizeof(target_ulong) equals to 4 on riscv32, so this change > does not change the function on riscv32. Second, sizeof(target_ulong) > equals to 8 on riscv64, and 'reg_index * 8 + i' is not a legal > pmp_index (we will explain later), which should be 'reg_index * 4 + i'. > > If the parameter reg_index equals to 2 (means that we will change the > value of pmpcfg2, or the second pmpcfg on riscv64), then > pmpcfg_csr_write(env, 2, val) will map write tasks to > pmp_write_cfg(env, 2 * 8 + [0...7], val). However, no cfg csr is indexed > by value 16 or 23 on riscv64, so we consider it as a bug. > > We are looking for constant (e.g., define a new constant named > RISCV_WORD_SIZE) in QEMU to help others understand code better, > but none was found. A possible good explanation of this literal is it is > the minimum word length on riscv is 4 bytes (32 bit). > > Signed-off-by: Hongzheng-Li <ethan.lee....@gmail.com> > Signed-off-by: Hou Weiying <weiying_...@outlook.com> > Signed-off-by: Myriad-Dreamin <camiy...@gmail.com>
Reviewed-by: Alistair Francis <alistair.fran...@wdc.com> Thanks! Applied to riscv-to-apply.next Alistair > --- > target/riscv/pmp.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/target/riscv/pmp.c b/target/riscv/pmp.c > index 2a2b9f5363..b14feeb7da 100644 > --- a/target/riscv/pmp.c > +++ b/target/riscv/pmp.c > @@ -320,8 +320,7 @@ void pmpcfg_csr_write(CPURISCVState *env, uint32_t > reg_index, > > for (i = 0; i < sizeof(target_ulong); i++) { > cfg_val = (val >> 8 * i) & 0xff; > - pmp_write_cfg(env, (reg_index * sizeof(target_ulong)) + i, > - cfg_val); > + pmp_write_cfg(env, (reg_index * 4) + i, cfg_val); > } > } > > @@ -336,7 +335,7 @@ target_ulong pmpcfg_csr_read(CPURISCVState *env, uint32_t > reg_index) > target_ulong val = 0; > > for (i = 0; i < sizeof(target_ulong); i++) { > - val = pmp_read_cfg(env, (reg_index * sizeof(target_ulong)) + i); > + val = pmp_read_cfg(env, (reg_index * 4) + i); > cfg_val |= (val << (i * 8)); > } > trace_pmpcfg_csr_read(env->mhartid, reg_index, cfg_val); > -- > 2.20.1 > >