| Message ID | 20230407033014.40901-1-liweiwei@iscas.ac.cn (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | target/riscv: Mask the implicitly enabled extensions in isa_string based on priv version | expand |
On 4/7/23 00:30, Weiwei Li wrote: > Using implicitly enabled extensions such as Zca/Zcf/Zcd instead of their > super extensions can simplify the extension related check. However, they > may have higher priv version than their super extensions. So we should mask > them in the isa_string based on priv version to make them invisible to user > if the specified priv version is lower than their minimal priv version. > > Signed-off-by: Weiwei Li <liweiwei@iscas.ac.cn> > Signed-off-by: Junqiang Wang <wangjunqiang@iscas.ac.cn> > --- > target/riscv/cpu.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c > index cb68916fce..1a5099382c 100644 > --- a/target/riscv/cpu.c > +++ b/target/riscv/cpu.c > @@ -1709,6 +1709,7 @@ static void riscv_isa_string_ext(RISCVCPU *cpu, char **isa_str, > > for (i = 0; i < ARRAY_SIZE(isa_edata_arr); i++) { > if (isa_edata_arr[i].multi_letter && > + (cpu->env.priv_ver >= isa_edata_arr[i].min_version) && We don't have a way of telling whether an extension was enabled by us or by the user. This will end up filtering user extensions from the isa_string. IMHO, the way the logic is working today, we can't enable Z extensions based on enabled MISA bits alone and disable extensions based on priv_spec at the same time. We would need to check for priv_version when enabling these extensions implicitly during realize(). Another alternative is to not disable any extensions at all based on priv spec - we send a warning about the priv mismatch and that's it. Thanks, Daniel > isa_ext_is_enabled(cpu, &isa_edata_arr[i])) { > new = g_strconcat(old, "_", isa_edata_arr[i].name, NULL); > g_free(old);
On 2023/4/7 18:58, Daniel Henrique Barboza wrote: > > > On 4/7/23 00:30, Weiwei Li wrote: >> Using implicitly enabled extensions such as Zca/Zcf/Zcd instead of their >> super extensions can simplify the extension related check. However, they >> may have higher priv version than their super extensions. So we >> should mask >> them in the isa_string based on priv version to make them invisible >> to user >> if the specified priv version is lower than their minimal priv version. >> >> Signed-off-by: Weiwei Li <liweiwei@iscas.ac.cn> >> Signed-off-by: Junqiang Wang <wangjunqiang@iscas.ac.cn> >> --- >> target/riscv/cpu.c | 1 + >> 1 file changed, 1 insertion(+) >> >> diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c >> index cb68916fce..1a5099382c 100644 >> --- a/target/riscv/cpu.c >> +++ b/target/riscv/cpu.c >> @@ -1709,6 +1709,7 @@ static void riscv_isa_string_ext(RISCVCPU *cpu, >> char **isa_str, >> for (i = 0; i < ARRAY_SIZE(isa_edata_arr); i++) { >> if (isa_edata_arr[i].multi_letter && >> + (cpu->env.priv_ver >= isa_edata_arr[i].min_version) && > > We don't have a way of telling whether an extension was enabled by us > or by the user. > This will end up filtering user extensions from the isa_string. As the method described in the https://lists.gnu.org/archive/html/qemu-riscv/2023-04/msg00200.html: The user specified extension have been disabled in realize(), So what needs masked is the implied extensions here. > > IMHO, the way the logic is working today, we can't enable Z extensions > based on enabled > MISA bits alone and disable extensions based on priv_spec at the same > time. We would > need to check for priv_version when enabling these extensions > implicitly during realize(). If we check this in realize(), we also need check them in support of the extension. So this is unnecessary. Regards, Weiwei Li > Another alternative is to not disable any extensions at all based on > priv spec - we send > a warning about the priv mismatch and that's it. > > > Thanks, > > Daniel > > > >> isa_ext_is_enabled(cpu, &isa_edata_arr[i])) { >> new = g_strconcat(old, "_", isa_edata_arr[i].name, NULL); >> g_free(old);
On 4/7/23 00:30, Weiwei Li wrote: > Using implicitly enabled extensions such as Zca/Zcf/Zcd instead of their > super extensions can simplify the extension related check. However, they > may have higher priv version than their super extensions. So we should mask > them in the isa_string based on priv version to make them invisible to user > if the specified priv version is lower than their minimal priv version. > > Signed-off-by: Weiwei Li <liweiwei@iscas.ac.cn> > Signed-off-by: Junqiang Wang <wangjunqiang@iscas.ac.cn> > --- Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com> And I'll fold it into the next version of "[PATCH v6 0/9] target/riscv: rework CPU extensions validation" to fix the sifive break I'm experiencing there. Thanks, Daniel > target/riscv/cpu.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c > index cb68916fce..1a5099382c 100644 > --- a/target/riscv/cpu.c > +++ b/target/riscv/cpu.c > @@ -1709,6 +1709,7 @@ static void riscv_isa_string_ext(RISCVCPU *cpu, char **isa_str, > > for (i = 0; i < ARRAY_SIZE(isa_edata_arr); i++) { > if (isa_edata_arr[i].multi_letter && > + (cpu->env.priv_ver >= isa_edata_arr[i].min_version) && > isa_ext_is_enabled(cpu, &isa_edata_arr[i])) { > new = g_strconcat(old, "_", isa_edata_arr[i].name, NULL); > g_free(old);
diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c index cb68916fce..1a5099382c 100644 --- a/target/riscv/cpu.c +++ b/target/riscv/cpu.c @@ -1709,6 +1709,7 @@ static void riscv_isa_string_ext(RISCVCPU *cpu, char **isa_str, for (i = 0; i < ARRAY_SIZE(isa_edata_arr); i++) { if (isa_edata_arr[i].multi_letter && + (cpu->env.priv_ver >= isa_edata_arr[i].min_version) && isa_ext_is_enabled(cpu, &isa_edata_arr[i])) { new = g_strconcat(old, "_", isa_edata_arr[i].name, NULL); g_free(old);