Extend fdt_parse_isa_extensions_all_harts() to also parse the
platform-defined RISC-V Worlds DT properties in /cpus/cpu at X:
- riscv,pmwid: M-mode World ID
- riscv,pmwidlist: bitmap of permitted M-mode WIDs
- riscv,pmlwidlist: bitmap of permitted lower-privilege WIDs
and store the parsed values in struct sbi_hart_features.
These platform-defined values serve as the root-of-trust constraints
for per-domain WID assignment during domain creation and context
switching.
Signed-off-by: Yu-Chien Peter Lin <peter.lin at sifive.com>
Reviewed-by: Anup Patel <anup at brainfault.org>
---
Changes v4->v5:
- No change
---
include/sbi/sbi_hart.h | 5 +++
lib/utils/fdt/fdt_helper.c | 69 ++++++++++++++++++++++++++++++++++----
2 files changed, 67 insertions(+), 7 deletions(-)
diff --git a/include/sbi/sbi_hart.h b/include/sbi/sbi_hart.h
index ed344783..629e3f64 100644
--- a/include/sbi/sbi_hart.h
+++ b/include/sbi/sbi_hart.h
@@ -138,6 +138,11 @@ struct sbi_hart_features {
unsigned int mhpm_mask;
unsigned int mhpm_bits;
unsigned long expected_trap;
+ u32 pmwid;
+ u64 pmwidlist;
+ u64 pmlwidlist;
+ bool has_pmwid;
+ bool has_pmlwidlist;
};
extern unsigned long hart_features_offset;
diff --git a/lib/utils/fdt/fdt_helper.c b/lib/utils/fdt/fdt_helper.c
index 747ba028..fdd25648 100644
--- a/lib/utils/fdt/fdt_helper.c
+++ b/lib/utils/fdt/fdt_helper.c
@@ -442,16 +442,71 @@ int fdt_parse_isa_extensions_all_harts(const void *fdt)
if (val && len > 0) {
fdt_parse_isa_extensions_one_hart((const char *)val,
hfeatures->extensions, len);
- continue;
+ } else {
+ val = fdt_getprop(fdt, cpu_offset, "riscv,isa", &len);
+ if (!val || len <= 0)
+ return SBI_ENOENT;
+
+ err = fdt_parse_isa_one_hart((const char *)val,
+ hfeatures->extensions);
+ if (err)
+ return err;
}
- val = fdt_getprop(fdt, cpu_offset, "riscv,isa", &len);
- if (!val || len <= 0)
- return SBI_ENOENT;
+ val = fdt_getprop(fdt, cpu_offset, "riscv,pmwid", &len);
+ if (val && len == sizeof(fdt32_t)) {
+ hfeatures->pmwid = fdt32_to_cpu(*val);
+ hfeatures->has_pmwid = true;
+ }
- err = fdt_parse_isa_one_hart((const char *)val, hfeatures->extensions);
- if (err)
- return err;
+ val = fdt_getprop(fdt, cpu_offset, "riscv,pmwidlist", &len);
+ if (val && len == 2 * sizeof(fdt32_t)) {
+ hfeatures->pmwidlist = ((u64)fdt32_to_cpu(val[0]) << 32) |
+ fdt32_to_cpu(val[1]);
+ if (!hfeatures->pmwidlist) {
+ sbi_printf("%s: hart%u riscv,pmwidlist is empty\n",
+ __func__, hartid);
+ return SBI_EINVAL;
+ }
+ }
+
+ val = fdt_getprop(fdt, cpu_offset, "riscv,pmlwidlist", &len);
+ if (val && len == 2 * sizeof(fdt32_t)) {
+ hfeatures->pmlwidlist = ((u64)fdt32_to_cpu(val[0]) << 32) |
+ fdt32_to_cpu(val[1]);
+ hfeatures->has_pmlwidlist = true;
+ }
+
+ /* Sanity checks */
+#if __riscv_xlen == 32
+ if (hfeatures->pmwidlist &&
+ (hfeatures->pmwidlist >> 32)) {
+ sbi_printf("%s: hart%u riscv,pmwidlist has bits beyond XLEN\n",
+ __func__, hartid);
+ return SBI_EINVAL;
+ }
+
+ if (hfeatures->has_pmlwidlist &&
+ (hfeatures->pmlwidlist >> 32)) {
+ sbi_printf("%s: hart%u riscv,pmlwidlist has bits beyond XLEN\n",
+ __func__, hartid);
+ return SBI_EINVAL;
+ }
+#endif
+
+ if (hfeatures->has_pmwid &&
+ hfeatures->pmwid >= __riscv_xlen) {
+ sbi_printf("%s: hart%u riscv,pmwid (%u) exceeds max WID\n",
+ __func__, hartid, hfeatures->pmwid);
+ return SBI_EINVAL;
+ }
+
+ if (hfeatures->pmwidlist && hfeatures->has_pmwid &&
+ !(hfeatures->pmwidlist & BIT_ULL(hfeatures->pmwid))) {
+ sbi_printf("%s: hart%u riscv,pmwid (%u) not in pmwidlist\n",
+ __func__, hartid, hfeatures->pmwid);
+ return SBI_EINVAL;
+ }
}
return 0;
--
2.43.7