[PATCH v4 1/2] lib: sbi: Add support for Svade and Svadu extensions

[Yong-Xuan Wang]

Add support for Svade and Svadu extensions. When both are present in the
device tree, the M-mode firmware should select the Svade extension
to comply with the RVA23 profile, which mandates Svade and lists Svadu as
an optional extension.

Signed-off-by: Yong-Xuan Wang <yongxuan.wang at sifive.com>
---
 include/sbi/riscv_encoding.h |  1 +
 include/sbi/sbi_hart.h       |  4 ++++
 lib/sbi/sbi_hart.c           | 12 ++++++++++++
 3 files changed, 17 insertions(+)

diff --git a/include/sbi/riscv_encoding.h b/include/sbi/riscv_encoding.h
index d914828e13af..477fa3a1ad86 100644
--- a/include/sbi/riscv_encoding.h
+++ b/include/sbi/riscv_encoding.h
@@ -211,6 +211,7 @@
 
 #define ENVCFG_STCE			(_ULL(1) << 63)
 #define ENVCFG_PBMTE			(_ULL(1) << 62)
+#define ENVCFG_ADUE			(_ULL(1) << 61)
 #define ENVCFG_CDE			(_ULL(1) << 60)
 #define ENVCFG_CBZE			(_UL(1) << 7)
 #define ENVCFG_CBCFE			(_UL(1) << 6)
diff --git a/include/sbi/sbi_hart.h b/include/sbi/sbi_hart.h
index cc78eec6f65a..81ec061d36a9 100644
--- a/include/sbi/sbi_hart.h
+++ b/include/sbi/sbi_hart.h
@@ -63,6 +63,10 @@ enum sbi_hart_extensions {
 	SBI_HART_EXT_SSCSRIND,
 	/** Hart has Ssccfg extension */
 	SBI_HART_EXT_SSCCFG,
+	/** Hart has Svade extension */
+	SBI_HART_EXT_SVADE,
+	/** Hart has Svadu extension */
+	SBI_HART_EXT_SVADU,
 
 	/** Maximum index of Hart extension */
 	SBI_HART_EXT_MAX,
diff --git a/lib/sbi/sbi_hart.c b/lib/sbi/sbi_hart.c
index cd974cc1a8da..c3667019b9a1 100644
--- a/lib/sbi/sbi_hart.c
+++ b/lib/sbi/sbi_hart.c
@@ -135,9 +135,19 @@ static void mstatus_init(struct sbi_scratch *scratch)
 #endif
 		__set_menvcfg_ext(SBI_HART_EXT_SSTC, ENVCFG_STCE)
 		__set_menvcfg_ext(SBI_HART_EXT_SMCDELEG, ENVCFG_CDE);
+		__set_menvcfg_ext(SBI_HART_EXT_SVADU, ENVCFG_ADUE);
 
 #undef __set_menvcfg_ext
 
+		/*
+		 * When both Svade and Svadu are present in DT, the default scheme for managing
+		 * the PTE A/D bits should use Svade. Check Svadu before Svade extension to ensure
+		 * that the ADUE bit is cleared when the Svade support are specified.
+		 */
+
+		if (sbi_hart_has_extension(scratch, SBI_HART_EXT_SVADE))
+			menvcfg_val &= ~ENVCFG_ADUE;
+
 		csr_write(CSR_MENVCFG, menvcfg_val);
 #if __riscv_xlen == 32
 		csr_write(CSR_MENVCFGH, menvcfg_val >> 32);
@@ -668,6 +678,8 @@ const struct sbi_hart_ext_data sbi_hart_ext[] = {
 	__SBI_HART_EXT_DATA(smcdeleg, SBI_HART_EXT_SMCDELEG),
 	__SBI_HART_EXT_DATA(sscsrind, SBI_HART_EXT_SSCSRIND),
 	__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),
 };
 
 _Static_assert(SBI_HART_EXT_MAX == array_size(sbi_hart_ext),
-- 
2.17.1