* [PATCH v1 1/2] riscv: Enhance extension probing
2025-01-06 13:04 [PATCH v1 0/2] Risc-V ISA Extension Probing Mayuresh Chitale
@ 2025-01-06 13:04 ` Mayuresh Chitale
2025-01-16 7:20 ` Leo Liang
2025-01-06 13:04 ` [PATCH v1 2/2] riscv: Fallback to riscv,isa Mayuresh Chitale
2025-01-06 14:38 ` [PATCH v1 0/2] Risc-V ISA Extension Probing Simon Glass
2 siblings, 1 reply; 6+ messages in thread
From: Mayuresh Chitale @ 2025-01-06 13:04 UTC (permalink / raw)
To: u-boot
Cc: Mayuresh Chitale, Rick Chen, Leo, Tom Rini, Conor Dooley,
Heinrich Schuchardt
Enhance the existing extension probing mechanism by adding support for
more extensions and probing using the "riscv,isa" property. This patch
is ported from the latest upstream linux.
Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
---
arch/riscv/cpu/cpu.c | 557 ++++++++++++++++++++++++++++
arch/riscv/include/asm/cpufeature.h | 37 ++
arch/riscv/include/asm/hwcap.h | 105 ++++++
3 files changed, 699 insertions(+)
create mode 100644 arch/riscv/include/asm/cpufeature.h
create mode 100644 arch/riscv/include/asm/hwcap.h
diff --git a/arch/riscv/cpu/cpu.c b/arch/riscv/cpu/cpu.c
index affe70081b5..f3f9f9f2351 100644
--- a/arch/riscv/cpu/cpu.c
+++ b/arch/riscv/cpu/cpu.c
@@ -14,8 +14,12 @@
#include <log.h>
#include <asm/encoding.h>
#include <asm/system.h>
+#include <asm/hwcap.h>
+#include <asm/cpufeature.h>
#include <dm/uclass-internal.h>
#include <linux/bitops.h>
+#include <linux/log2.h>
+#include <linux/ctype.h>
/*
* The variables here must be stored in the data section since they are used
@@ -33,6 +37,559 @@ u32 available_harts_lock = 1;
#endif
#endif
+/* Host ISA bitmap */
+static DECLARE_BITMAP(riscv_isa, RISCV_ISA_EXT_MAX) __section(".data");
+
+static unsigned int riscv_cbom_block_size __section(".data");
+static unsigned int riscv_cboz_block_size __section(".data");
+/**
+ * __riscv_isa_extension_available() - Check whether given extension
+ * is available or not
+ *
+ * @bit: bit position of the desired extension
+ * Return: true or false
+ *
+ */
+static bool __riscv_isa_extension_available(unsigned int bit)
+{
+ if (bit >= RISCV_ISA_EXT_MAX)
+ return false;
+
+ return test_bit(bit, riscv_isa) ? true : false;
+}
+
+inline unsigned int riscv_get_cbom_block_size(void)
+{
+ return riscv_cbom_block_size;
+}
+
+inline unsigned int riscv_get_cboz_block_size(void)
+{
+ return riscv_cboz_block_size;
+}
+
+static int riscv_ext_zicbom_validate(const struct riscv_isa_ext_data *data,
+ const unsigned long *isa_bitmap)
+{
+ struct udevice *dev;
+
+ if (!CONFIG_IS_ENABLED(RISCV_ISA_ZICBOM) || riscv_cbom_block_size)
+ return 0;
+
+ uclass_first_device(UCLASS_CPU, &dev);
+ if (!dev) {
+ log_info("Failed to get cpu device!\n");
+ return -ENXIO;
+ }
+
+ if (!dev_read_u32(dev, "riscv,cbom-block-size",
+ &riscv_cbom_block_size)) {
+ if (!riscv_cbom_block_size) {
+ log_err("Zicbom detected in ISA string, disabling as no cbom-block-size found\n");
+ return -EINVAL;
+ }
+ if (!is_power_of_2(riscv_cbom_block_size)) {
+ log_err("Zicbom disabled as cbom-block-size present, but is not a power-of-2\n");
+ return -EINVAL;
+ }
+ return 0;
+ } else {
+ return -EINVAL;
+ }
+}
+
+static int riscv_ext_zicboz_validate(const struct riscv_isa_ext_data *data,
+ const unsigned long *isa_bitmap)
+{
+ struct udevice *dev;
+
+ if (!CONFIG_IS_ENABLED(RISCV_ISA_ZICBOM) || riscv_cboz_block_size)
+ return 0;
+
+ uclass_first_device(UCLASS_CPU, &dev);
+ if (!dev) {
+ log_debug("Failed to get cpu device!\n");
+ return -ENXIO;
+ }
+
+ if (!dev_read_u32(dev, "riscv,cboz-block-size",
+ &riscv_cboz_block_size)) {
+ if (!riscv_cboz_block_size) {
+ log_err("Zicboz detected in ISA string, disabling as no cboz-block-size found\n");
+ return -EINVAL;
+ }
+ if (!is_power_of_2(riscv_cboz_block_size)) {
+ log_err("Zicboz disabled as cboz-block-size present, but is not a power-of-2\n");
+ return -EINVAL;
+ }
+ return 0;
+ } else {
+ return -EINVAL;
+ }
+}
+
+static int riscv_ext_zca_depends(const struct riscv_isa_ext_data *data,
+ const unsigned long *isa_bitmap)
+{
+ if (__riscv_isa_extension_available(RISCV_ISA_EXT_ZCA))
+ return 0;
+
+ return -EINVAL;
+}
+
+static int riscv_ext_zcd_validate(const struct riscv_isa_ext_data *data,
+ const unsigned long *isa_bitmap)
+{
+ if (__riscv_isa_extension_available(RISCV_ISA_EXT_ZCA) &&
+ __riscv_isa_extension_available(RISCV_ISA_EXT_d))
+ return 0;
+
+ return -EINVAL;
+}
+
+static int riscv_ext_zcf_validate(const struct riscv_isa_ext_data *data,
+ const unsigned long *isa_bitmap)
+{
+ if (IS_ENABLED(CONFIG_64BIT))
+ return -EINVAL;
+
+ if (__riscv_isa_extension_available(RISCV_ISA_EXT_ZCA) &&
+ __riscv_isa_extension_available(RISCV_ISA_EXT_f))
+ return 0;
+
+ return -EINVAL;
+}
+
+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
+};
+
+#define RISCV_ISA_EXT_ZVKN \
+ RISCV_ISA_EXT_ZVKNED, \
+ RISCV_ISA_EXT_ZVKNHB, \
+ RISCV_ISA_EXT_ZVKB, \
+ RISCV_ISA_EXT_ZVKT
+
+static const unsigned int riscv_zvkn_bundled_exts[] = {
+ RISCV_ISA_EXT_ZVKN
+};
+
+static const unsigned int riscv_zvknc_bundled_exts[] = {
+ RISCV_ISA_EXT_ZVKN,
+ RISCV_ISA_EXT_ZVBC
+};
+
+static const unsigned int riscv_zvkng_bundled_exts[] = {
+ RISCV_ISA_EXT_ZVKN,
+ RISCV_ISA_EXT_ZVKG
+};
+
+#define RISCV_ISA_EXT_ZVKS \
+ RISCV_ISA_EXT_ZVKSED, \
+ RISCV_ISA_EXT_ZVKSH, \
+ RISCV_ISA_EXT_ZVKB, \
+ RISCV_ISA_EXT_ZVKT
+
+static const unsigned int riscv_zvks_bundled_exts[] = {
+ RISCV_ISA_EXT_ZVKS
+};
+
+static const unsigned int riscv_zvksc_bundled_exts[] = {
+ RISCV_ISA_EXT_ZVKS,
+ RISCV_ISA_EXT_ZVBC
+};
+
+static const unsigned int riscv_zvksg_bundled_exts[] = {
+ RISCV_ISA_EXT_ZVKS,
+ RISCV_ISA_EXT_ZVKG
+};
+
+static const unsigned int riscv_zvbb_exts[] = {
+ RISCV_ISA_EXT_ZVKB
+};
+
+#define RISCV_ISA_EXT_ZVE64F_IMPLY_LIST \
+ RISCV_ISA_EXT_ZVE64X, \
+ RISCV_ISA_EXT_ZVE32F, \
+ RISCV_ISA_EXT_ZVE32X
+
+#define RISCV_ISA_EXT_ZVE64D_IMPLY_LIST \
+ RISCV_ISA_EXT_ZVE64F, \
+ RISCV_ISA_EXT_ZVE64F_IMPLY_LIST
+
+#define RISCV_ISA_EXT_V_IMPLY_LIST \
+ RISCV_ISA_EXT_ZVE64D, \
+ RISCV_ISA_EXT_ZVE64D_IMPLY_LIST
+
+static const unsigned int riscv_zve32f_exts[] = {
+ RISCV_ISA_EXT_ZVE32X
+};
+
+static const unsigned int riscv_zve64f_exts[] = {
+ RISCV_ISA_EXT_ZVE64F_IMPLY_LIST
+};
+
+static const unsigned int riscv_zve64d_exts[] = {
+ RISCV_ISA_EXT_ZVE64D_IMPLY_LIST
+};
+
+static const unsigned int riscv_v_exts[] = {
+ RISCV_ISA_EXT_V_IMPLY_LIST
+};
+
+static const unsigned int riscv_zve64x_exts[] = {
+ RISCV_ISA_EXT_ZVE32X,
+ RISCV_ISA_EXT_ZVE64X
+};
+
+/*
+ * While the [ms]envcfg CSRs were not defined until version 1.12 of the RISC-V
+ * privileged ISA, the existence of the CSRs is implied by any extension which
+ * specifies [ms]envcfg bit(s). Hence, we define a custom ISA extension for the
+ * existence of the CSR, and treat it as a subset of those other extensions.
+ */
+static const unsigned int riscv_xlinuxenvcfg_exts[] = {
+ RISCV_ISA_EXT_XLINUXENVCFG
+};
+
+/*
+ * Zc* spec states that:
+ * - C always implies Zca
+ * - C+F implies Zcf (RV32 only)
+ * - C+D implies Zcd
+ *
+ * These extensions will be enabled and then validated depending on the
+ * availability of F/D RV32.
+ */
+static const unsigned int riscv_c_exts[] = {
+ RISCV_ISA_EXT_ZCA,
+ RISCV_ISA_EXT_ZCF,
+ RISCV_ISA_EXT_ZCD,
+};
+
+/*
+ * The canonical order of ISA extension names in the ISA string is defined in
+ * chapter 27 of the unprivileged specification.
+ *
+ * Ordinarily, for in-kernel data structures, this order is unimportant but
+ * isa_ext_arr defines the order of the ISA string in /proc/cpuinfo.
+ *
+ * The specification uses vague wording, such as should, when it comes to
+ * ordering, so for our purposes the following rules apply:
+ *
+ * 1. All multi-letter extensions must be separated from other extensions by an
+ * underscore.
+ *
+ * 2. Additional standard extensions (starting with 'Z') must be sorted after
+ * single-letter extensions and before any higher-privileged extensions.
+ *
+ * 3. The first letter following the 'Z' conventionally indicates the most
+ * closely related alphabetical extension category, IMAFDQLCBKJTPVH.
+ * If multiple 'Z' extensions are named, they must be ordered first by
+ * category, then alphabetically within a category.
+ *
+ * 3. Standard supervisor-level extensions (starting with 'S') must be listed
+ * after standard unprivileged extensions. If multiple supervisor-level
+ * extensions are listed, they must be ordered alphabetically.
+ *
+ * 4. Standard machine-level extensions (starting with 'Zxm') must be listed
+ * after any lower-privileged, standard extensions. If multiple
+ * machine-level extensions are listed, they must be ordered
+ * alphabetically.
+ *
+ * 5. Non-standard extensions (starting with 'X') must be listed after all
+ * standard extensions. If multiple non-standard extensions are listed, they
+ * must be ordered alphabetically.
+ *
+ * An example string following the order is:
+ * rv64imadc_zifoo_zigoo_zafoo_sbar_scar_zxmbaz_xqux_xrux
+ *
+ * New entries to this struct should follow the ordering rules described above.
+ */
+const struct riscv_isa_ext_data riscv_isa_ext[] = {
+ __RISCV_ISA_EXT_DATA(i, RISCV_ISA_EXT_i),
+ __RISCV_ISA_EXT_DATA(m, RISCV_ISA_EXT_m),
+ __RISCV_ISA_EXT_DATA(a, RISCV_ISA_EXT_a),
+ __RISCV_ISA_EXT_DATA(f, RISCV_ISA_EXT_f),
+ __RISCV_ISA_EXT_DATA(d, RISCV_ISA_EXT_d),
+ __RISCV_ISA_EXT_DATA(q, RISCV_ISA_EXT_q),
+ __RISCV_ISA_EXT_SUPERSET(c, RISCV_ISA_EXT_c, riscv_c_exts),
+ __RISCV_ISA_EXT_SUPERSET(v, RISCV_ISA_EXT_v, riscv_v_exts),
+ __RISCV_ISA_EXT_DATA(h, RISCV_ISA_EXT_h),
+ __RISCV_ISA_EXT_SUPERSET_VALIDATE(zicbom, RISCV_ISA_EXT_ZICBOM, riscv_xlinuxenvcfg_exts,
+ riscv_ext_zicbom_validate),
+ __RISCV_ISA_EXT_SUPERSET_VALIDATE(zicboz, RISCV_ISA_EXT_ZICBOZ, riscv_xlinuxenvcfg_exts,
+ riscv_ext_zicboz_validate),
+ __RISCV_ISA_EXT_DATA(zicntr, RISCV_ISA_EXT_ZICNTR),
+ __RISCV_ISA_EXT_DATA(zicond, RISCV_ISA_EXT_ZICOND),
+ __RISCV_ISA_EXT_DATA(zicsr, RISCV_ISA_EXT_ZICSR),
+ __RISCV_ISA_EXT_DATA(zifencei, RISCV_ISA_EXT_ZIFENCEI),
+ __RISCV_ISA_EXT_DATA(zihintntl, RISCV_ISA_EXT_ZIHINTNTL),
+ __RISCV_ISA_EXT_DATA(zihintpause, RISCV_ISA_EXT_ZIHINTPAUSE),
+ __RISCV_ISA_EXT_DATA(zihpm, RISCV_ISA_EXT_ZIHPM),
+ __RISCV_ISA_EXT_DATA(zimop, RISCV_ISA_EXT_ZIMOP),
+ __RISCV_ISA_EXT_DATA(zacas, RISCV_ISA_EXT_ZACAS),
+ __RISCV_ISA_EXT_DATA(zawrs, RISCV_ISA_EXT_ZAWRS),
+ __RISCV_ISA_EXT_DATA(zfa, RISCV_ISA_EXT_ZFA),
+ __RISCV_ISA_EXT_DATA(zfh, RISCV_ISA_EXT_ZFH),
+ __RISCV_ISA_EXT_DATA(zfhmin, RISCV_ISA_EXT_ZFHMIN),
+ __RISCV_ISA_EXT_DATA(zca, RISCV_ISA_EXT_ZCA),
+ __RISCV_ISA_EXT_DATA_VALIDATE(zcb, RISCV_ISA_EXT_ZCB, riscv_ext_zca_depends),
+ __RISCV_ISA_EXT_DATA_VALIDATE(zcd, RISCV_ISA_EXT_ZCD, riscv_ext_zcd_validate),
+ __RISCV_ISA_EXT_DATA_VALIDATE(zcf, RISCV_ISA_EXT_ZCF, riscv_ext_zcf_validate),
+ __RISCV_ISA_EXT_DATA_VALIDATE(zcmop, RISCV_ISA_EXT_ZCMOP, riscv_ext_zca_depends),
+ __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(ztso, RISCV_ISA_EXT_ZTSO),
+ __RISCV_ISA_EXT_SUPERSET(zvbb, RISCV_ISA_EXT_ZVBB, riscv_zvbb_exts),
+ __RISCV_ISA_EXT_DATA(zvbc, RISCV_ISA_EXT_ZVBC),
+ __RISCV_ISA_EXT_SUPERSET(zve32f, RISCV_ISA_EXT_ZVE32F, riscv_zve32f_exts),
+ __RISCV_ISA_EXT_DATA(zve32x, RISCV_ISA_EXT_ZVE32X),
+ __RISCV_ISA_EXT_SUPERSET(zve64d, RISCV_ISA_EXT_ZVE64D, riscv_zve64d_exts),
+ __RISCV_ISA_EXT_SUPERSET(zve64f, RISCV_ISA_EXT_ZVE64F, riscv_zve64f_exts),
+ __RISCV_ISA_EXT_SUPERSET(zve64x, RISCV_ISA_EXT_ZVE64X, riscv_zve64x_exts),
+ __RISCV_ISA_EXT_DATA(zvfh, RISCV_ISA_EXT_ZVFH),
+ __RISCV_ISA_EXT_DATA(zvfhmin, RISCV_ISA_EXT_ZVFHMIN),
+ __RISCV_ISA_EXT_DATA(zvkb, RISCV_ISA_EXT_ZVKB),
+ __RISCV_ISA_EXT_DATA(zvkg, RISCV_ISA_EXT_ZVKG),
+ __RISCV_ISA_EXT_BUNDLE(zvkn, riscv_zvkn_bundled_exts),
+ __RISCV_ISA_EXT_BUNDLE(zvknc, riscv_zvknc_bundled_exts),
+ __RISCV_ISA_EXT_DATA(zvkned, RISCV_ISA_EXT_ZVKNED),
+ __RISCV_ISA_EXT_BUNDLE(zvkng, riscv_zvkng_bundled_exts),
+ __RISCV_ISA_EXT_DATA(zvknha, RISCV_ISA_EXT_ZVKNHA),
+ __RISCV_ISA_EXT_DATA(zvknhb, RISCV_ISA_EXT_ZVKNHB),
+ __RISCV_ISA_EXT_BUNDLE(zvks, riscv_zvks_bundled_exts),
+ __RISCV_ISA_EXT_BUNDLE(zvksc, riscv_zvksc_bundled_exts),
+ __RISCV_ISA_EXT_DATA(zvksed, RISCV_ISA_EXT_ZVKSED),
+ __RISCV_ISA_EXT_DATA(zvksh, RISCV_ISA_EXT_ZVKSH),
+ __RISCV_ISA_EXT_BUNDLE(zvksg, riscv_zvksg_bundled_exts),
+ __RISCV_ISA_EXT_DATA(zvkt, RISCV_ISA_EXT_ZVKT),
+ __RISCV_ISA_EXT_DATA(smaia, RISCV_ISA_EXT_SMAIA),
+ __RISCV_ISA_EXT_DATA(smmpm, RISCV_ISA_EXT_SMMPM),
+ __RISCV_ISA_EXT_SUPERSET(smnpm, RISCV_ISA_EXT_SMNPM, riscv_xlinuxenvcfg_exts),
+ __RISCV_ISA_EXT_DATA(smstateen, RISCV_ISA_EXT_SMSTATEEN),
+ __RISCV_ISA_EXT_DATA(ssaia, RISCV_ISA_EXT_SSAIA),
+ __RISCV_ISA_EXT_DATA(sscofpmf, RISCV_ISA_EXT_SSCOFPMF),
+ __RISCV_ISA_EXT_SUPERSET(ssnpm, RISCV_ISA_EXT_SSNPM, riscv_xlinuxenvcfg_exts),
+ __RISCV_ISA_EXT_DATA(sstc, RISCV_ISA_EXT_SSTC),
+ __RISCV_ISA_EXT_DATA(svinval, RISCV_ISA_EXT_SVINVAL),
+ __RISCV_ISA_EXT_DATA(svnapot, RISCV_ISA_EXT_SVNAPOT),
+ __RISCV_ISA_EXT_DATA(svpbmt, RISCV_ISA_EXT_SVPBMT),
+ __RISCV_ISA_EXT_DATA(svvptc, RISCV_ISA_EXT_SVVPTC),
+};
+
+const size_t riscv_isa_ext_count = ARRAY_SIZE(riscv_isa_ext);
+
+static void riscv_isa_set_ext(const struct riscv_isa_ext_data *ext, unsigned long *bitmap)
+{
+ if (ext->id != RISCV_ISA_EXT_INVALID)
+ __set_bit(ext->id, bitmap);
+
+ for (int i = 0; i < ext->subset_ext_size; i++) {
+ if (ext->subset_ext_ids[i] != RISCV_ISA_EXT_INVALID)
+ __set_bit(ext->subset_ext_ids[i], bitmap);
+ }
+}
+
+static void match_isa_ext(const char *name, const char *name_end)
+{
+ for (int i = 0; i < riscv_isa_ext_count; i++) {
+ const struct riscv_isa_ext_data *ext = &riscv_isa_ext[i];
+
+ if ((name_end - name == strlen(ext->name)) &&
+ !strncasecmp(name, ext->name, name_end - name)) {
+ if (ext->validate && !ext->validate(ext, riscv_isa))
+ riscv_isa_set_ext(ext, riscv_isa);
+ break;
+ }
+ }
+}
+
+static void riscv_parse_isa_string(const char *isa)
+{
+ /*
+ * For all possible cpus, we have already validated in
+ * the boot process that they at least contain "rv" and
+ * whichever of "32"/"64" this kernel supports, and so this
+ * section can be skipped.
+ */
+ isa += 4;
+
+ while (*isa) {
+ const char *ext = isa++;
+ const char *ext_end = isa;
+ bool ext_err = false;
+
+ switch (*ext) {
+ case 'x':
+ case 'X':
+ log_warning("Vendor extensions are ignored in riscv,isa. Use riscv,isa-extensions instead.");
+ /*
+ * To skip an extension, we find its end.
+ * As multi-letter extensions must be split from other multi-letter
+ * extensions with an "_", the end of a multi-letter extension will
+ * either be the null character or the "_" at the start of the next
+ * multi-letter extension.
+ */
+ for (; *isa && *isa != '_'; ++isa)
+ ;
+ ext_err = true;
+ break;
+ case 's':
+ /*
+ * Workaround for invalid single-letter 's' & 'u' (QEMU).
+ * No need to set the bit in riscv_isa as 's' & 'u' are
+ * not valid ISA extensions. It works unless the first
+ * multi-letter extension in the ISA string begins with
+ * "Su" and is not prefixed with an underscore.
+ */
+ if (ext[-1] != '_' && ext[1] == 'u') {
+ ++isa;
+ ext_err = true;
+ break;
+ }
+ fallthrough;
+ case 'S':
+ case 'z':
+ case 'Z':
+ /*
+ * Before attempting to parse the extension itself, we find its end.
+ * As multi-letter extensions must be split from other multi-letter
+ * extensions with an "_", the end of a multi-letter extension will
+ * either be the null character or the "_" at the start of the next
+ * multi-letter extension.
+ *
+ * Next, as the extensions version is currently ignored, we
+ * eliminate that portion. This is done by parsing backwards from
+ * the end of the extension, removing any numbers. This may be a
+ * major or minor number however, so the process is repeated if a
+ * minor number was found.
+ *
+ * ext_end is intended to represent the first character *after* the
+ * name portion of an extension, but will be decremented to the last
+ * character itself while eliminating the extensions version number.
+ * A simple re-increment solves this problem.
+ */
+ for (; *isa && *isa != '_'; ++isa)
+ if (unlikely(!isalnum(*isa)))
+ ext_err = true;
+
+ ext_end = isa;
+ if (unlikely(ext_err))
+ break;
+
+ if (!isdigit(ext_end[-1]))
+ break;
+
+ while (isdigit(*--ext_end))
+ ;
+
+ if (tolower(ext_end[0]) != 'p' || !isdigit(ext_end[-1])) {
+ ++ext_end;
+ break;
+ }
+
+ while (isdigit(*--ext_end))
+ ;
+
+ ++ext_end;
+ break;
+ default:
+ /*
+ * Things are a little easier for single-letter extensions, as they
+ * are parsed forwards.
+ *
+ * After checking that our starting position is valid, we need to
+ * ensure that, when isa was incremented at the start of the loop,
+ * that it arrived at the start of the next extension.
+ *
+ * If we are already on a non-digit, there is nothing to do. Either
+ * we have a multi-letter extension's _, or the start of an
+ * extension.
+ *
+ * Otherwise we have found the current extension's major version
+ * number. Parse past it, and a subsequent p/minor version number
+ * if present. The `p` extension must not appear immediately after
+ * a number, so there is no fear of missing it.
+ *
+ */
+ if (unlikely(!isalpha(*ext))) {
+ ext_err = true;
+ break;
+ }
+
+ if (!isdigit(*isa))
+ break;
+
+ while (isdigit(*++isa))
+ ;
+
+ if (tolower(*isa) != 'p')
+ break;
+
+ if (!isdigit(*++isa)) {
+ --isa;
+ break;
+ }
+
+ while (isdigit(*++isa))
+ ;
+
+ break;
+ }
+
+ /*
+ * The parser expects that at the start of an iteration isa points to the
+ * first character of the next extension. As we stop parsing an extension
+ * on meeting a non-alphanumeric character, an extra increment is needed
+ * where the succeeding extension is a multi-letter prefixed with an "_".
+ */
+ if (*isa == '_')
+ ++isa;
+
+ if (unlikely(ext_err))
+ continue;
+ match_isa_ext(ext, ext_end);
+ }
+}
+
static inline bool supports_extension(char ext)
{
#if CONFIG_IS_ENABLED(RISCV_MMODE)
diff --git a/arch/riscv/include/asm/cpufeature.h b/arch/riscv/include/asm/cpufeature.h
new file mode 100644
index 00000000000..655180c993e
--- /dev/null
+++ b/arch/riscv/include/asm/cpufeature.h
@@ -0,0 +1,37 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef _ASM_CPUFEATURE_H
+#define _ASM_CPUFEATURE_H
+struct riscv_isa_ext_data {
+ const unsigned int id;
+ const char *name;
+ const char *property;
+ const unsigned int *subset_ext_ids;
+ const unsigned int subset_ext_size;
+ int (*validate)(const struct riscv_isa_ext_data *data, const unsigned long *isa_bitmap);
+};
+
+#define _RISCV_ISA_EXT_DATA(_name, _id, _subset_exts, _subset_exts_size, _validate) { \
+ .name = #_name, \
+ .property = #_name, \
+ .id = _id, \
+ .subset_ext_ids = _subset_exts, \
+ .subset_ext_size = _subset_exts_size, \
+ .validate = _validate \
+}
+
+#define __RISCV_ISA_EXT_DATA(_name, _id) _RISCV_ISA_EXT_DATA(_name, _id, NULL, 0, NULL)
+#define __RISCV_ISA_EXT_DATA_VALIDATE(_name, _id, _validate) \
+ _RISCV_ISA_EXT_DATA(_name, _id, NULL, 0, _validate)
+
+/* Used to declare pure "lasso" extension (Zk for instance) */
+#define __RISCV_ISA_EXT_BUNDLE(_name, _bundled_exts) \
+ _RISCV_ISA_EXT_DATA(_name, RISCV_ISA_EXT_INVALID, _bundled_exts, \
+ ARRAY_SIZE(_bundled_exts), NULL)
+
+/* Used to declare extensions that are a superset of other extensions (Zvbb for instance) */
+#define __RISCV_ISA_EXT_SUPERSET(_name, _id, _sub_exts) \
+ _RISCV_ISA_EXT_DATA(_name, _id, _sub_exts, ARRAY_SIZE(_sub_exts), NULL)
+#define __RISCV_ISA_EXT_SUPERSET_VALIDATE(_name, _id, _sub_exts, _validate) \
+ _RISCV_ISA_EXT_DATA(_name, _id, _sub_exts, ARRAY_SIZE(_sub_exts), _validate)
+#endif
diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h
new file mode 100644
index 00000000000..aa68ada6b2b
--- /dev/null
+++ b/arch/riscv/include/asm/hwcap.h
@@ -0,0 +1,105 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _ASM_RISCV_HWCAP_H
+#define _ASM_RISCV_HWCAP_H
+
+#define RISCV_ISA_EXT_a ('a' - 'a')
+#define RISCV_ISA_EXT_c ('c' - 'a')
+#define RISCV_ISA_EXT_d ('d' - 'a')
+#define RISCV_ISA_EXT_f ('f' - 'a')
+#define RISCV_ISA_EXT_h ('h' - 'a')
+#define RISCV_ISA_EXT_i ('i' - 'a')
+#define RISCV_ISA_EXT_m ('m' - 'a')
+#define RISCV_ISA_EXT_q ('q' - 'a')
+#define RISCV_ISA_EXT_v ('v' - 'a')
+
+/*
+ * These macros represent the logical IDs of each multi-letter RISC-V ISA
+ * extension and are used in the ISA bitmap. The logical IDs start from
+ * RISCV_ISA_EXT_BASE, which allows the 0-25 range to be reserved for single
+ * letter extensions. The maximum, RISCV_ISA_EXT_MAX, is defined in order
+ * to allocate the bitmap and may be increased when necessary.
+ *
+ * New extensions should just be added to the bottom, rather than added
+ * alphabetically, in order to avoid unnecessary shuffling.
+ */
+#define RISCV_ISA_EXT_BASE 26
+
+#define RISCV_ISA_EXT_SSCOFPMF 26
+#define RISCV_ISA_EXT_SSTC 27
+#define RISCV_ISA_EXT_SVINVAL 28
+#define RISCV_ISA_EXT_SVPBMT 29
+#define RISCV_ISA_EXT_ZBB 30
+#define RISCV_ISA_EXT_ZICBOM 31
+#define RISCV_ISA_EXT_ZIHINTPAUSE 32
+#define RISCV_ISA_EXT_SVNAPOT 33
+#define RISCV_ISA_EXT_ZICBOZ 34
+#define RISCV_ISA_EXT_SMAIA 35
+#define RISCV_ISA_EXT_SSAIA 36
+#define RISCV_ISA_EXT_ZBA 37
+#define RISCV_ISA_EXT_ZBS 38
+#define RISCV_ISA_EXT_ZICNTR 39
+#define RISCV_ISA_EXT_ZICSR 40
+#define RISCV_ISA_EXT_ZIFENCEI 41
+#define RISCV_ISA_EXT_ZIHPM 42
+#define RISCV_ISA_EXT_SMSTATEEN 43
+#define RISCV_ISA_EXT_ZICOND 44
+#define RISCV_ISA_EXT_ZBC 45
+#define RISCV_ISA_EXT_ZBKB 46
+#define RISCV_ISA_EXT_ZBKC 47
+#define RISCV_ISA_EXT_ZBKX 48
+#define RISCV_ISA_EXT_ZKND 49
+#define RISCV_ISA_EXT_ZKNE 50
+#define RISCV_ISA_EXT_ZKNH 51
+#define RISCV_ISA_EXT_ZKR 52
+#define RISCV_ISA_EXT_ZKSED 53
+#define RISCV_ISA_EXT_ZKSH 54
+#define RISCV_ISA_EXT_ZKT 55
+#define RISCV_ISA_EXT_ZVBB 56
+#define RISCV_ISA_EXT_ZVBC 57
+#define RISCV_ISA_EXT_ZVKB 58
+#define RISCV_ISA_EXT_ZVKG 59
+#define RISCV_ISA_EXT_ZVKNED 60
+#define RISCV_ISA_EXT_ZVKNHA 61
+#define RISCV_ISA_EXT_ZVKNHB 62
+#define RISCV_ISA_EXT_ZVKSED 63
+#define RISCV_ISA_EXT_ZVKSH 64
+#define RISCV_ISA_EXT_ZVKT 65
+#define RISCV_ISA_EXT_ZFH 66
+#define RISCV_ISA_EXT_ZFHMIN 67
+#define RISCV_ISA_EXT_ZIHINTNTL 68
+#define RISCV_ISA_EXT_ZVFH 69
+#define RISCV_ISA_EXT_ZVFHMIN 70
+#define RISCV_ISA_EXT_ZFA 71
+#define RISCV_ISA_EXT_ZTSO 72
+#define RISCV_ISA_EXT_ZACAS 73
+#define RISCV_ISA_EXT_ZVE32X 74
+#define RISCV_ISA_EXT_ZVE32F 75
+#define RISCV_ISA_EXT_ZVE64X 76
+#define RISCV_ISA_EXT_ZVE64F 77
+#define RISCV_ISA_EXT_ZVE64D 78
+#define RISCV_ISA_EXT_ZIMOP 79
+#define RISCV_ISA_EXT_ZCA 80
+#define RISCV_ISA_EXT_ZCB 81
+#define RISCV_ISA_EXT_ZCD 82
+#define RISCV_ISA_EXT_ZCF 83
+#define RISCV_ISA_EXT_ZCMOP 84
+#define RISCV_ISA_EXT_ZAWRS 85
+#define RISCV_ISA_EXT_SVVPTC 86
+#define RISCV_ISA_EXT_SMMPM 87
+#define RISCV_ISA_EXT_SMNPM 88
+#define RISCV_ISA_EXT_SSNPM 89
+
+#define RISCV_ISA_EXT_XLINUXENVCFG 127
+
+#define RISCV_ISA_EXT_MAX 128
+#define RISCV_ISA_EXT_INVALID U32_MAX
+
+#ifdef CONFIG_RISCV_M_MODE
+#define RISCV_ISA_EXT_SxAIA RISCV_ISA_EXT_SMAIA
+#define RISCV_ISA_EXT_SUPM RISCV_ISA_EXT_SMNPM
+#else
+#define RISCV_ISA_EXT_SxAIA RISCV_ISA_EXT_SSAIA
+#define RISCV_ISA_EXT_SUPM RISCV_ISA_EXT_SSNPM
+#endif
+
+#endif /* _ASM_RISCV_HWCAP_H */
--
2.34.1
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