[PATCH v2 02/19] riscv: add ISA extension parsing for scalar crypto
From: Clément Léger
Date: Tue Oct 17 2023 - 09:15:43 EST
From: Evan Green <evan@xxxxxxxxxxxx>
The Scalar Crypto specification defines Zk as a shorthand for the
Zkn, Zkr and Zkt extensions. The same follows for both Zkn, Zks and Zbk,
which are all shorthands for various other extensions. The detailed
breakdown can be found in their dt-binding entries.
Since Zkn also implies the Zbkb, Zbkc and Zbkx extensions, simply passing
"zk" through a DT should enable all of Zbkb, Zbkc, Zbkx, Zkn, Zkr and Zkt.
For example, setting the "riscv,isa" DT property to "rv64imafdc_zk"
should generate the following cpuinfo output:
"rv64imafdc_zicntr_zicsr_zifencei_zihpm_zbkb_zbkc_zbkx_zknd_zkne_zknh_zkr_zkt"
riscv_isa_ext_data grows a pair of new members, to permit setting the
relevant bits for "bundled" extensions, both while parsing the ISA string
and the new dedicated extension properties
Co-developed-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
Signed-off-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
Signed-off-by: Evan Green <evan@xxxxxxxxxxxx>
Signed-off-by: Clément Léger <cleger@xxxxxxxxxxxx>
---
arch/riscv/include/asm/hwcap.h | 13 +++++
arch/riscv/kernel/cpufeature.c | 103 ++++++++++++++++++++++++++-------
2 files changed, 96 insertions(+), 20 deletions(-)
diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h
index b7b58258f6c7..ab80d822c847 100644
--- a/arch/riscv/include/asm/hwcap.h
+++ b/arch/riscv/include/asm/hwcap.h
@@ -58,6 +58,17 @@
#define RISCV_ISA_EXT_ZICSR 40
#define RISCV_ISA_EXT_ZIFENCEI 41
#define RISCV_ISA_EXT_ZIHPM 42
+#define RISCV_ISA_EXT_ZBC 43
+#define RISCV_ISA_EXT_ZBKB 44
+#define RISCV_ISA_EXT_ZBKC 45
+#define RISCV_ISA_EXT_ZBKX 46
+#define RISCV_ISA_EXT_ZKND 47
+#define RISCV_ISA_EXT_ZKNE 48
+#define RISCV_ISA_EXT_ZKNH 49
+#define RISCV_ISA_EXT_ZKR 50
+#define RISCV_ISA_EXT_ZKSED 51
+#define RISCV_ISA_EXT_ZKSH 52
+#define RISCV_ISA_EXT_ZKT 53
#define RISCV_ISA_EXT_MAX 64
@@ -77,6 +88,8 @@ struct riscv_isa_ext_data {
const unsigned int id;
const char *name;
const char *property;
+ const unsigned int *bundle_ids;
+ const unsigned int bundle_size;
};
extern const struct riscv_isa_ext_data riscv_isa_ext[];
diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
index 1cfbba65d11a..d3682fdfd9f1 100644
--- a/arch/riscv/kernel/cpufeature.c
+++ b/arch/riscv/kernel/cpufeature.c
@@ -111,6 +111,39 @@ static bool riscv_isa_extension_check(int id)
.id = _id, \
}
+#define __RISCV_ISA_EXT_BUNDLE(_name, _bundled_exts) { \
+ .name = #_name, \
+ .property = #_name, \
+ .bundle_ids = _bundled_exts, \
+ .bundle_size = ARRAY_SIZE(_bundled_exts) \
+}
+
+static const unsigned int riscv_zk_bundled_exts[] = {
+ RISCV_ISA_EXT_ZBKB,
+ RISCV_ISA_EXT_ZBKC,
+ RISCV_ISA_EXT_ZBKX,
+ RISCV_ISA_EXT_ZKND,
+ RISCV_ISA_EXT_ZKNE,
+ RISCV_ISA_EXT_ZKR,
+ RISCV_ISA_EXT_ZKT,
+};
+
+static const unsigned int riscv_zkn_bundled_exts[] = {
+ RISCV_ISA_EXT_ZBKB,
+ RISCV_ISA_EXT_ZBKC,
+ RISCV_ISA_EXT_ZBKX,
+ RISCV_ISA_EXT_ZKND,
+ RISCV_ISA_EXT_ZKNE,
+ RISCV_ISA_EXT_ZKNH,
+};
+
+static const unsigned int riscv_zks_bundled_exts[] = {
+ RISCV_ISA_EXT_ZBKB,
+ RISCV_ISA_EXT_ZBKC,
+ RISCV_ISA_EXT_ZKSED,
+ RISCV_ISA_EXT_ZKSH
+};
+
/*
* The canonical order of ISA extension names in the ISA string is defined in
* chapter 27 of the unprivileged specification.
@@ -173,7 +206,21 @@ const struct riscv_isa_ext_data riscv_isa_ext[] = {
__RISCV_ISA_EXT_DATA(zihpm, RISCV_ISA_EXT_ZIHPM),
__RISCV_ISA_EXT_DATA(zba, RISCV_ISA_EXT_ZBA),
__RISCV_ISA_EXT_DATA(zbb, RISCV_ISA_EXT_ZBB),
+ __RISCV_ISA_EXT_DATA(zbc, RISCV_ISA_EXT_ZBC),
+ __RISCV_ISA_EXT_DATA(zbkb, RISCV_ISA_EXT_ZBKB),
+ __RISCV_ISA_EXT_DATA(zbkc, RISCV_ISA_EXT_ZBKC),
+ __RISCV_ISA_EXT_DATA(zbkx, RISCV_ISA_EXT_ZBKX),
__RISCV_ISA_EXT_DATA(zbs, RISCV_ISA_EXT_ZBS),
+ __RISCV_ISA_EXT_BUNDLE(zk, riscv_zk_bundled_exts),
+ __RISCV_ISA_EXT_BUNDLE(zkn, riscv_zkn_bundled_exts),
+ __RISCV_ISA_EXT_DATA(zknd, RISCV_ISA_EXT_ZKND),
+ __RISCV_ISA_EXT_DATA(zkne, RISCV_ISA_EXT_ZKNE),
+ __RISCV_ISA_EXT_DATA(zknh, RISCV_ISA_EXT_ZKNH),
+ __RISCV_ISA_EXT_DATA(zkr, RISCV_ISA_EXT_ZKR),
+ __RISCV_ISA_EXT_BUNDLE(zks, riscv_zks_bundled_exts),
+ __RISCV_ISA_EXT_DATA(zkt, RISCV_ISA_EXT_ZKT),
+ __RISCV_ISA_EXT_DATA(zksed, RISCV_ISA_EXT_ZKSED),
+ __RISCV_ISA_EXT_DATA(zksh, RISCV_ISA_EXT_ZKSH),
__RISCV_ISA_EXT_DATA(smaia, RISCV_ISA_EXT_SMAIA),
__RISCV_ISA_EXT_DATA(ssaia, RISCV_ISA_EXT_SSAIA),
__RISCV_ISA_EXT_DATA(sscofpmf, RISCV_ISA_EXT_SSCOFPMF),
@@ -185,6 +232,26 @@ const struct riscv_isa_ext_data riscv_isa_ext[] = {
const size_t riscv_isa_ext_count = ARRAY_SIZE(riscv_isa_ext);
+static void __init match_isa_ext(const struct riscv_isa_ext_data *ext, const char *name,
+ const char *name_end, struct riscv_isainfo *isainfo)
+{
+ if ((name_end - name == strlen(ext->name)) &&
+ !strncasecmp(name, ext->name, name_end - name)) {
+ /*
+ * If this is a bundle, enable all the ISA extensions that
+ * comprise the bundle.
+ */
+ if (ext->bundle_size) {
+ for (int i = 0; i < ext->bundle_size; i++) {
+ if (riscv_isa_extension_check(ext->bundle_ids[i]))
+ set_bit(ext->bundle_ids[i], isainfo->isa);
+ }
+ } else if (riscv_isa_extension_check(ext->id)) {
+ set_bit(ext->id, isainfo->isa);
+ }
+ }
+}
+
static void __init riscv_parse_isa_string(unsigned long *this_hwcap, struct riscv_isainfo *isainfo,
unsigned long *isa2hwcap, const char *isa)
{
@@ -316,14 +383,6 @@ static void __init riscv_parse_isa_string(unsigned long *this_hwcap, struct risc
if (*isa == '_')
++isa;
-#define SET_ISA_EXT_MAP(name, bit) \
- do { \
- if ((ext_end - ext == strlen(name)) && \
- !strncasecmp(ext, name, strlen(name)) && \
- riscv_isa_extension_check(bit)) \
- set_bit(bit, isainfo->isa); \
- } while (false) \
-
if (unlikely(ext_err))
continue;
if (!ext_long) {
@@ -335,10 +394,8 @@ static void __init riscv_parse_isa_string(unsigned long *this_hwcap, struct risc
}
} else {
for (int i = 0; i < riscv_isa_ext_count; i++)
- SET_ISA_EXT_MAP(riscv_isa_ext[i].name,
- riscv_isa_ext[i].id);
+ match_isa_ext(&riscv_isa_ext[i], ext, ext_end, isainfo);
}
-#undef SET_ISA_EXT_MAP
}
}
@@ -437,18 +494,24 @@ static int __init riscv_fill_hwcap_from_ext_list(unsigned long *isa2hwcap)
}
for (int i = 0; i < riscv_isa_ext_count; i++) {
- if (of_property_match_string(cpu_node, "riscv,isa-extensions",
- riscv_isa_ext[i].property) < 0)
- continue;
+ const struct riscv_isa_ext_data ext = riscv_isa_ext[i];
- if (!riscv_isa_extension_check(riscv_isa_ext[i].id))
+ if (of_property_match_string(cpu_node, "riscv,isa-extensions",
+ ext.property) < 0)
continue;
- /* Only single letter extensions get set in hwcap */
- if (strnlen(riscv_isa_ext[i].name, 2) == 1)
- this_hwcap |= isa2hwcap[riscv_isa_ext[i].id];
-
- set_bit(riscv_isa_ext[i].id, isainfo->isa);
+ if (ext.bundle_size) {
+ for (int j = 0; j < ext.bundle_size; j++) {
+ if (riscv_isa_extension_check(ext.bundle_ids[i]))
+ set_bit(ext.bundle_ids[j], isainfo->isa);
+ }
+ } else if (riscv_isa_extension_check(ext.id)) {
+ set_bit(ext.id, isainfo->isa);
+
+ /* Only single letter extensions get set in hwcap */
+ if (strnlen(riscv_isa_ext[i].name, 2) == 1)
+ this_hwcap |= isa2hwcap[riscv_isa_ext[i].id];
+ }
}
of_node_put(cpu_node);
--
2.42.0