target/riscv/cpu.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 60 insertions(+)
The Linux kernel parses the ISA extensions from "riscv,isa" DT
property. It used to parse only the single letter base extensions
until now. A generic ISA extension parsing framework was proposed[1]
recently that can parse multi-letter ISA extensions as well.
Generate the extended ISA string by appending the available ISA extensions
to the "riscv,isa" string if it is enabled so that kernel can process it.
[1] https://lkml.org/lkml/2022/2/15/263
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Suggested-by: Heiko Stubner <heiko@sntech.de>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
---
Changes from v6->v7:
1. Fixed indentation and typo.
2. Added Reviewed-by tags.
Changes from v5->v6:
1. Improved commit message.
2. Fixed a typo for Zfh.
Changes from v4->v5:
1. Fixed the order of Zxx extensions.
2. Added a comment clearly describing the rules of extension order.
Changes from v3->v4:
1. Fixed the order of the extension names.
2. Added all the available ISA extensions in Qemu.
Changes from v2->v3:
1. Used g_strconcat to replace snprintf & a max isa string length as
suggested by Anup.
2. I have not included the Tested-by Tag from Heiko because the
implementation changed from v2 to v3.
Changes from v1->v2:
1. Improved the code redability by using arrays instead of individual check
---
target/riscv/cpu.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 60 insertions(+)
diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index 198274fb34e5..86e48ff54dd1 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -34,6 +34,11 @@
/* RISC-V CPU definitions */
+struct isa_ext_data {
+ const char *name;
+ bool enabled;
+};
+
static const char riscv_exts[26] = "IEMAFDQCLBJTPVNSUHKORWXYZG";
const char * const riscv_int_regnames[] = {
@@ -920,6 +925,60 @@ static void riscv_cpu_class_init(ObjectClass *c, void *data)
device_class_set_props(dc, riscv_cpu_properties);
}
+#define ISA_EDATA_ENTRY(name, prop) {#name, cpu->cfg.prop}
+
+static void riscv_isa_string_ext(RISCVCPU *cpu, char **isa_str, int max_str_len)
+{
+ char *old = *isa_str;
+ char *new = *isa_str;
+ int i;
+
+ /**
+ * Here are the ordering rules of extension naming defined by RISC-V
+ * specification :
+ * 1. All extensions should be separated from other multi-letter extensions
+ * by an underscore.
+ * 2. The first letter following the 'Z' conventionally indicates the most
+ * closely related alphabetical extension category, IMAFDQLCBKJTPVH.
+ * If multiple 'Z' extensions are named, they should be ordered first
+ * by category, then alphabetically within a category.
+ * 3. Standard supervisor-level extensions (starts with 'S') should be
+ * listed after standard unprivileged extensions. If multiple
+ * supervisor-level extensions are listed, they should be ordered
+ * alphabetically.
+ * 4. Non-standard extensions (starts with 'X') must be listed after all
+ * standard extensions. They must be separated from other multi-letter
+ * extensions by an underscore.
+ */
+ struct isa_ext_data isa_edata_arr[] = {
+ ISA_EDATA_ENTRY(zfh, ext_zfh),
+ ISA_EDATA_ENTRY(zfhmin, ext_zfhmin),
+ ISA_EDATA_ENTRY(zfinx, ext_zfinx),
+ ISA_EDATA_ENTRY(zhinx, ext_zhinx),
+ ISA_EDATA_ENTRY(zhinxmin, ext_zhinxmin),
+ ISA_EDATA_ENTRY(zdinx, ext_zdinx),
+ ISA_EDATA_ENTRY(zba, ext_zba),
+ ISA_EDATA_ENTRY(zbb, ext_zbb),
+ ISA_EDATA_ENTRY(zbc, ext_zbc),
+ ISA_EDATA_ENTRY(zbs, ext_zbs),
+ ISA_EDATA_ENTRY(zve32f, ext_zve32f),
+ ISA_EDATA_ENTRY(zve64f, ext_zve64f),
+ ISA_EDATA_ENTRY(svinval, ext_svinval),
+ ISA_EDATA_ENTRY(svnapot, ext_svnapot),
+ ISA_EDATA_ENTRY(svpbmt, ext_svpbmt),
+ };
+
+ for (i = 0; i < ARRAY_SIZE(isa_edata_arr); i++) {
+ if (isa_edata_arr[i].enabled) {
+ new = g_strconcat(old, "_", isa_edata_arr[i].name, NULL);
+ g_free(old);
+ old = new;
+ }
+ }
+
+ *isa_str = new;
+}
+
char *riscv_isa_string(RISCVCPU *cpu)
{
int i;
@@ -932,6 +991,7 @@ char *riscv_isa_string(RISCVCPU *cpu)
}
}
*p = '\0';
+ riscv_isa_string_ext(cpu, &isa_str, maxlen);
return isa_str;
}
--
2.25.1
On Wed, Mar 30, 2022 at 5:59 AM Atish Patra <atishp@rivosinc.com> wrote: > > The Linux kernel parses the ISA extensions from "riscv,isa" DT > property. It used to parse only the single letter base extensions > until now. A generic ISA extension parsing framework was proposed[1] > recently that can parse multi-letter ISA extensions as well. > > Generate the extended ISA string by appending the available ISA extensions > to the "riscv,isa" string if it is enabled so that kernel can process it. > > [1] https://lkml.org/lkml/2022/2/15/263 > > Reviewed-by: Anup Patel <anup@brainfault.org> > Reviewed-by: Alistair Francis <alistair.francis@wdc.com> > Reviewed-by: Frank Chang <frank.chang@sifive.com> > Reviewed-by: Bin Meng <bmeng.cn@gmail.com> > Tested-by: Bin Meng <bmeng.cn@gmail.com> > Suggested-by: Heiko Stubner <heiko@sntech.de> > Signed-off-by: Atish Patra <atishp@rivosinc.com> Thanks! Applied to riscv-to-apply.next Alistair > --- > > Changes from v6->v7: > 1. Fixed indentation and typo. > 2. Added Reviewed-by tags. > > Changes from v5->v6: > 1. Improved commit message. > 2. Fixed a typo for Zfh. > > Changes from v4->v5: > 1. Fixed the order of Zxx extensions. > 2. Added a comment clearly describing the rules of extension order. > > Changes from v3->v4: > 1. Fixed the order of the extension names. > 2. Added all the available ISA extensions in Qemu. > > Changes from v2->v3: > 1. Used g_strconcat to replace snprintf & a max isa string length as > suggested by Anup. > 2. I have not included the Tested-by Tag from Heiko because the > implementation changed from v2 to v3. > > Changes from v1->v2: > 1. Improved the code redability by using arrays instead of individual check > --- > target/riscv/cpu.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 60 insertions(+) > > diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c > index 198274fb34e5..86e48ff54dd1 100644 > --- a/target/riscv/cpu.c > +++ b/target/riscv/cpu.c > @@ -34,6 +34,11 @@ > > /* RISC-V CPU definitions */ > > +struct isa_ext_data { > + const char *name; > + bool enabled; > +}; > + > static const char riscv_exts[26] = "IEMAFDQCLBJTPVNSUHKORWXYZG"; > > const char * const riscv_int_regnames[] = { > @@ -920,6 +925,60 @@ static void riscv_cpu_class_init(ObjectClass *c, void *data) > device_class_set_props(dc, riscv_cpu_properties); > } > > +#define ISA_EDATA_ENTRY(name, prop) {#name, cpu->cfg.prop} > + > +static void riscv_isa_string_ext(RISCVCPU *cpu, char **isa_str, int max_str_len) > +{ > + char *old = *isa_str; > + char *new = *isa_str; > + int i; > + > + /** > + * Here are the ordering rules of extension naming defined by RISC-V > + * specification : > + * 1. All extensions should be separated from other multi-letter extensions > + * by an underscore. > + * 2. The first letter following the 'Z' conventionally indicates the most > + * closely related alphabetical extension category, IMAFDQLCBKJTPVH. > + * If multiple 'Z' extensions are named, they should be ordered first > + * by category, then alphabetically within a category. > + * 3. Standard supervisor-level extensions (starts with 'S') should be > + * listed after standard unprivileged extensions. If multiple > + * supervisor-level extensions are listed, they should be ordered > + * alphabetically. > + * 4. Non-standard extensions (starts with 'X') must be listed after all > + * standard extensions. They must be separated from other multi-letter > + * extensions by an underscore. > + */ > + struct isa_ext_data isa_edata_arr[] = { > + ISA_EDATA_ENTRY(zfh, ext_zfh), > + ISA_EDATA_ENTRY(zfhmin, ext_zfhmin), > + ISA_EDATA_ENTRY(zfinx, ext_zfinx), > + ISA_EDATA_ENTRY(zhinx, ext_zhinx), > + ISA_EDATA_ENTRY(zhinxmin, ext_zhinxmin), > + ISA_EDATA_ENTRY(zdinx, ext_zdinx), > + ISA_EDATA_ENTRY(zba, ext_zba), > + ISA_EDATA_ENTRY(zbb, ext_zbb), > + ISA_EDATA_ENTRY(zbc, ext_zbc), > + ISA_EDATA_ENTRY(zbs, ext_zbs), > + ISA_EDATA_ENTRY(zve32f, ext_zve32f), > + ISA_EDATA_ENTRY(zve64f, ext_zve64f), > + ISA_EDATA_ENTRY(svinval, ext_svinval), > + ISA_EDATA_ENTRY(svnapot, ext_svnapot), > + ISA_EDATA_ENTRY(svpbmt, ext_svpbmt), > + }; > + > + for (i = 0; i < ARRAY_SIZE(isa_edata_arr); i++) { > + if (isa_edata_arr[i].enabled) { > + new = g_strconcat(old, "_", isa_edata_arr[i].name, NULL); > + g_free(old); > + old = new; > + } > + } > + > + *isa_str = new; > +} > + > char *riscv_isa_string(RISCVCPU *cpu) > { > int i; > @@ -932,6 +991,7 @@ char *riscv_isa_string(RISCVCPU *cpu) > } > } > *p = '\0'; > + riscv_isa_string_ext(cpu, &isa_str, maxlen); > return isa_str; > } > > -- > 2.25.1 > >
© 2016 - 2024 Red Hat, Inc.