@@ -213,6 +213,10 @@
#define ENVCFG_PBMTE (_ULL(1) << 62)
#define ENVCFG_ADUE (_ULL(1) << 61)
#define ENVCFG_CDE (_ULL(1) << 60)
+#define ENVCFG_PMM (_ULL(0x3) << 32)
+#define ENVCFG_PMM_PMLEN_0 (_ULL(0x0) << 32)
+#define ENVCFG_PMM_PMLEN_7 (_ULL(0x2) << 32)
+#define ENVCFG_PMM_PMLEN_16 (_ULL(0x3) << 32)
#define ENVCFG_CBZE (_UL(1) << 7)
#define ENVCFG_CBCFE (_UL(1) << 6)
#define ENVCFG_CBIE_SHIFT 4
@@ -128,7 +128,8 @@ enum sbi_fwft_feature_t {
SBI_FWFT_SHADOW_STACK = 0x2,
SBI_FWFT_DOUBLE_TRAP = 0x3,
SBI_FWFT_PTE_AD_HW_UPDATING = 0x4,
- SBI_FWFT_LOCAL_RESERVED_START = 0x5,
+ SBI_FWFT_POINTER_MASKING_PMLEN = 0x5,
+ SBI_FWFT_LOCAL_RESERVED_START = 0x6,
SBI_FWFT_LOCAL_RESERVED_END = 0x3fffffff,
SBI_FWFT_LOCAL_PLATFORM_START = 0x40000000,
SBI_FWFT_LOCAL_PLATFORM_END = 0x7fffffff,
@@ -67,6 +67,8 @@ enum sbi_hart_extensions {
SBI_HART_EXT_SVADE,
/** Hart has Svadu extension */
SBI_HART_EXT_SVADU,
+ /** Hart has Smnpm extension */
+ SBI_HART_EXT_SMNPM,
/** Maximum index of Hart extension */
SBI_HART_EXT_MAX,
@@ -59,6 +59,7 @@ static const unsigned long fwft_defined_features[] = {
SBI_FWFT_SHADOW_STACK,
SBI_FWFT_DOUBLE_TRAP,
SBI_FWFT_PTE_AD_HW_UPDATING,
+ SBI_FWFT_POINTER_MASKING_PMLEN,
};
static bool fwft_is_defined_feature(enum sbi_fwft_feature_t feature)
@@ -145,6 +146,64 @@ static int fwft_get_adue(struct fwft_config *conf, unsigned long *value)
return SBI_OK;
}
+#if __riscv_xlen > 32
+static int fwft_pmlen_supported(struct fwft_config *conf)
+{
+ if (!sbi_hart_has_extension(sbi_scratch_thishart_ptr(),
+ SBI_HART_EXT_SMNPM))
+ return SBI_ENOTSUPP;
+
+ return SBI_OK;
+}
+
+static bool fwft_try_to_set_pmm(unsigned long pmm)
+{
+ csr_set(CSR_MENVCFG, pmm);
+ return (csr_read(CSR_MENVCFG) & ENVCFG_PMM) == pmm;
+}
+
+static int fwft_set_pmlen(struct fwft_config *conf, unsigned long value)
+{
+ unsigned long prev;
+
+ if (value > 16)
+ return SBI_EINVAL;
+
+ prev = csr_read_clear(CSR_MENVCFG, ENVCFG_PMM);
+ if (value == 0)
+ return SBI_OK;
+ if (value <= 7) {
+ if (fwft_try_to_set_pmm(ENVCFG_PMM_PMLEN_7))
+ return SBI_OK;
+ csr_clear(CSR_MENVCFG, ENVCFG_PMM);
+ }
+ if (fwft_try_to_set_pmm(ENVCFG_PMM_PMLEN_16))
+ return SBI_OK;
+ csr_write(CSR_MENVCFG, prev);
+
+ return SBI_EINVAL;
+}
+
+static int fwft_get_pmlen(struct fwft_config *conf, unsigned long *value)
+{
+ switch (csr_read(CSR_MENVCFG) & ENVCFG_PMM) {
+ case ENVCFG_PMM_PMLEN_0:
+ *value = 0;
+ break;
+ case ENVCFG_PMM_PMLEN_7:
+ *value = 7;
+ break;
+ case ENVCFG_PMM_PMLEN_16:
+ *value = 16;
+ break;
+ default:
+ return SBI_EFAIL;
+ }
+
+ return SBI_OK;
+}
+#endif
+
static struct fwft_config* get_feature_config(enum sbi_fwft_feature_t feature)
{
int i;
@@ -236,6 +295,14 @@ static const struct fwft_feature features[] =
.set = fwft_set_adue,
.get = fwft_get_adue,
},
+#if __riscv_xlen > 32
+ {
+ .id = SBI_FWFT_POINTER_MASKING_PMLEN,
+ .supported = fwft_pmlen_supported,
+ .set = fwft_set_pmlen,
+ .get = fwft_get_pmlen,
+ },
+#endif
};
int sbi_fwft_init(struct sbi_scratch *scratch, bool cold_boot)
@@ -680,6 +680,7 @@ const struct sbi_hart_ext_data sbi_hart_ext[] = {
__SBI_HART_EXT_DATA(ssccfg, SBI_HART_EXT_SSCCFG),
__SBI_HART_EXT_DATA(svade, SBI_HART_EXT_SVADE),
__SBI_HART_EXT_DATA(svadu, SBI_HART_EXT_SVADU),
+ __SBI_HART_EXT_DATA(smnpm, SBI_HART_EXT_SMNPM),
};
_Static_assert(SBI_HART_EXT_MAX == array_size(sbi_hart_ext),
Add support for controlling the pointer masking mode on harts which support the Smnpm extension. This extension can only exist on harts where XLEN >= 64 bits. This implementation selects the mode with the smallest PMLEN that satisfies the caller's requested lower bound. Signed-off-by: Samuel Holland <samuel.holland@sifive.com> --- This patch implements the API I originally suggested while the FWFT extension was a draft and also submitted here: https://github.com/riscv-non-isa/riscv-sbi-doc/pull/161 include/sbi/riscv_encoding.h | 4 ++ include/sbi/sbi_ecall_interface.h | 3 +- include/sbi/sbi_hart.h | 2 + lib/sbi/sbi_fwft.c | 67 +++++++++++++++++++++++++++++++ lib/sbi/sbi_hart.c | 1 + 5 files changed, 76 insertions(+), 1 deletion(-)