[RFC PATCH 1/1] lib/sbi: Enable menvcfg.CDE for Sspesa

[Mayuresh Chitale]

The Sspesa (Precise Event Sample Attribution) extension exposes the
shpmspc and shpmsdata CSRs and S-mode access to these CSRs is gated by
menvcfg.CDE. Hence set menvcfg.CDE when Sspesa is enabled.

Signed-off-by: Mayuresh Chitale <mayuresh.chitale at oss.qualcomm.com>
---
 include/sbi/riscv_encoding.h | 4 ++++
 include/sbi/sbi_hart.h       | 2 ++
 lib/sbi/sbi_hart.c           | 7 ++++++-
 3 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/include/sbi/riscv_encoding.h b/include/sbi/riscv_encoding.h
index ffe7666c..12cc0b0c 100644
--- a/include/sbi/riscv_encoding.h
+++ b/include/sbi/riscv_encoding.h
@@ -751,6 +751,10 @@
 /* Counter Overflow CSR */
 #define CSR_SCOUNTOVF			0xda0
 
+/* Temporary addresses for Sspesa (Precise Event Sample Attribution) CSRs. */
+#define CSR_SHPMSPC			0x5d0
+#define CSR_SHPMSDATA			0x5d1
+
 /* Debug/Trace Registers */
 #define CSR_TSELECT			0x7a0
 #define CSR_TDATA1			0x7a1
diff --git a/include/sbi/sbi_hart.h b/include/sbi/sbi_hart.h
index 543393bb..2abdc504 100644
--- a/include/sbi/sbi_hart.h
+++ b/include/sbi/sbi_hart.h
@@ -95,6 +95,8 @@ enum sbi_hart_extensions {
 	SBI_HART_EXT_F,
 	/** Hart has D extension */
 	SBI_HART_EXT_D,
+	/** Hart has Sspesa extension */
+	SBI_HART_EXT_SSPESA,
 
 	/** Maximum index of Hart extension */
 	SBI_HART_EXT_MAX,
diff --git a/lib/sbi/sbi_hart.c b/lib/sbi/sbi_hart.c
index bee88557..783a0773 100644
--- a/lib/sbi/sbi_hart.c
+++ b/lib/sbi/sbi_hart.c
@@ -160,7 +160,8 @@ static void mstatus_init(struct sbi_scratch *scratch)
 		__set_menvcfg_ext(SBI_HART_EXT_SVPBMT, ENVCFG_PBMTE)
 #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_SMCDELEG, ENVCFG_CDE)
+		__set_menvcfg_ext(SBI_HART_EXT_SSPESA, ENVCFG_CDE);
 
 		/*
 		 * Assume only Svadu is supported when it is the only extension
@@ -360,6 +361,7 @@ const struct sbi_hart_ext_data sbi_hart_ext[] = {
 	__SBI_HART_EXT_DATA(v, SBI_HART_EXT_V),
 	__SBI_HART_EXT_DATA(f, SBI_HART_EXT_F),
 	__SBI_HART_EXT_DATA(d, SBI_HART_EXT_D),
+	__SBI_HART_EXT_DATA(sspesa, SBI_HART_EXT_SSPESA),
 };
 
 _Static_assert(SBI_HART_EXT_MAX == array_size(sbi_hart_ext),
@@ -629,6 +631,9 @@ __pmp_skip:
 	/* Detect if hart supports sscofpmf */
 	__check_ext_csr(SBI_HART_PRIV_VER_1_11,
 			CSR_SCOUNTOVF, SBI_HART_EXT_SSCOFPMF);
+	/* Detect if hart supports Sspesa (precise sample attribution) */
+	__check_ext_csr(SBI_HART_PRIV_VER_1_12,
+			CSR_SHPMSPC, SBI_HART_EXT_SSPESA);
 	/* Detect if hart has AIA local interrupt CSRs */
 	__check_ext_csr(SBI_HART_PRIV_VER_UNKNOWN,
 			CSR_MTOPI, SBI_HART_EXT_SMAIA);
-- 
2.43.0