[PATCH 0/6] lib: sbi: sse: spec update and fixes

[PATCH 0/6] lib: sbi: sse: spec update and fixes

[Clément Léger]

The SBI specification added a few new events as well as specifying
sse_write_attrs() invalid attributes errors. Also handle new fields
to be saved (SPELP, SDT) upon injection.

Cl?ment L?ger (6):
  lib: sbi: sse: Update SSE event ids
  lib: sbi: sse: Fix format string for event invalid state
  lib: sbi: sse: Return SBI_EDENIED for read only parameters.
  lib: sbi: sse: Rename STATUS* interrupted flags to SSTATUS*
  lib: sbi: sse: Add support for SSTATUS.SPELP
  lib: sbi: sse: Add support for SSTATUS.SDT

 include/sbi/riscv_encoding.h      |  3 +-
 include/sbi/sbi_ecall_interface.h | 50 ++++++++++++++++++++++++-------
 lib/sbi/sbi_pmu.c                 |  4 +--
 lib/sbi/sbi_sse.c                 | 50 +++++++++++++++++++++----------
 4 files changed, 78 insertions(+), 29 deletions(-)

-- 
2.47.2

[PATCH 1/6] lib: sbi: sse: Update SSE event ids

[Clément Léger]

The latest specification added new high priority RAS events and renamed
the PMU to PMU_OVERFLOW.

Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>
---
 include/sbi/sbi_ecall_interface.h | 44 ++++++++++++++++++++++++-------
 lib/sbi/sbi_pmu.c                 |  4 +--
 lib/sbi/sbi_sse.c                 |  8 +++---
 3 files changed, 42 insertions(+), 14 deletions(-)

diff --git a/include/sbi/sbi_ecall_interface.h b/include/sbi/sbi_ecall_interface.h
index a7dab8c3..bd694aa8 100644
--- a/include/sbi/sbi_ecall_interface.h
+++ b/include/sbi/sbi_ecall_interface.h
@@ -393,34 +393,60 @@ enum sbi_sse_state {
 };
 
 /* SBI SSE Event IDs. */
-#define SBI_SSE_EVENT_LOCAL_RAS			0x00000000
+/* Range 0x00000000 - 0x0000ffff */
+#define SBI_SSE_EVENT_LOCAL_HIGH_PRIO_RAS	0x00000000
 #define SBI_SSE_EVENT_LOCAL_DOUBLE_TRAP		0x00000001
+#define SBI_SSE_EVENT_LOCAL_RESERVED_0_START	0x00000002
+#define SBI_SSE_EVENT_LOCAL_RESERVED_0_END	0x00003fff
 #define SBI_SSE_EVENT_LOCAL_PLAT_0_START	0x00004000
 #define SBI_SSE_EVENT_LOCAL_PLAT_0_END		0x00007fff
-#define SBI_SSE_EVENT_GLOBAL_RAS		0x00008000
+
+#define SBI_SSE_EVENT_GLOBAL_HIGH_PRIO_RAS	0x00008000
+#define SBI_SSE_EVENT_GLOBAL_RESERVED_0_START	0x00008001
+#define SBI_SSE_EVENT_GLOBAL_RESERVED_0_END	0x0000bfff
 #define SBI_SSE_EVENT_GLOBAL_PLAT_0_START	0x0000c000
 #define SBI_SSE_EVENT_GLOBAL_PLAT_0_END		0x0000ffff
 
-#define SBI_SSE_EVENT_LOCAL_PMU			0x00010000
+/* Range 0x00010000 - 0x0001ffff */
+#define SBI_SSE_EVENT_LOCAL_PMU_OVERFLOW	0x00010000
+#define SBI_SSE_EVENT_LOCAL_RESERVED_1_START	0x00010001
+#define SBI_SSE_EVENT_LOCAL_RESERVED_1_END	0x00013fff
 #define SBI_SSE_EVENT_LOCAL_PLAT_1_START	0x00014000
 #define SBI_SSE_EVENT_LOCAL_PLAT_1_END		0x00017fff
+
+#define SBI_SSE_EVENT_GLOBAL_RESERVED_1_START	0x00018000
+#define SBI_SSE_EVENT_GLOBAL_RESERVED_1_END	0x0001bfff
 #define SBI_SSE_EVENT_GLOBAL_PLAT_1_START	0x0001c000
 #define SBI_SSE_EVENT_GLOBAL_PLAT_1_END		0x0001ffff
 
-#define SBI_SSE_EVENT_LOCAL_PLAT_2_START	0x00024000
-#define SBI_SSE_EVENT_LOCAL_PLAT_2_END		0x00027fff
-#define SBI_SSE_EVENT_GLOBAL_PLAT_2_START	0x0002c000
-#define SBI_SSE_EVENT_GLOBAL_PLAT_2_END		0x0002ffff
+/* Range 0x00100000 - 0x0010ffff */
+#define SBI_SSE_EVENT_LOCAL_LOW_PRIO_RAS	0x00100000
+#define SBI_SSE_EVENT_LOCAL_RESERVED_2_START	0x00100001
+#define SBI_SSE_EVENT_LOCAL_RESERVED_2_END	0x00103fff
+#define SBI_SSE_EVENT_LOCAL_PLAT_2_START	0x00104000
+#define SBI_SSE_EVENT_LOCAL_PLAT_2_END		0x00107fff
 
+#define SBI_SSE_EVENT_GLOBAL_LOW_PRIO_RAS	0x00108000
+#define SBI_SSE_EVENT_GLOBAL_RESERVED_2_START	0x00108001
+#define SBI_SSE_EVENT_GLOBAL_RESERVED_2_END	0x0010bfff
+#define SBI_SSE_EVENT_GLOBAL_PLAT_2_START	0x0010c000
+#define SBI_SSE_EVENT_GLOBAL_PLAT_2_END		0x0010ffff
+
+/* Range 0xffff0000 - 0xffffffff */
 #define SBI_SSE_EVENT_LOCAL_SOFTWARE		0xffff0000
+#define SBI_SSE_EVENT_LOCAL_RESERVED_3_START	0xffff0001
+#define SBI_SSE_EVENT_LOCAL_RESERVED_3_END	0xffff3fff
 #define SBI_SSE_EVENT_LOCAL_PLAT_3_START	0xffff4000
 #define SBI_SSE_EVENT_LOCAL_PLAT_3_END		0xffff7fff
+
 #define SBI_SSE_EVENT_GLOBAL_SOFTWARE		0xffff8000
+#define SBI_SSE_EVENT_GLOBAL_RESERVED_3_START	0xffff8001
+#define SBI_SSE_EVENT_GLOBAL_RESERVED_3_END	0xffffbfff
 #define SBI_SSE_EVENT_GLOBAL_PLAT_3_START	0xffffc000
 #define SBI_SSE_EVENT_GLOBAL_PLAT_3_END		0xffffffff
 
-#define SBI_SSE_EVENT_GLOBAL_BIT		(1 << 15)
-#define SBI_SSE_EVENT_PLATFORM_BIT		(1 << 14)
+#define SBI_SSE_EVENT_GLOBAL_BIT		BIT(15)
+#define SBI_SSE_EVENT_PLATFORM_BIT		BIT(14)
 
 /* SBI function IDs for MPXY extension */
 #define SBI_EXT_MPXY_GET_SHMEM_SIZE		0x0
diff --git a/lib/sbi/sbi_pmu.c b/lib/sbi/sbi_pmu.c
index 40b898fe..4f113c23 100644
--- a/lib/sbi/sbi_pmu.c
+++ b/lib/sbi/sbi_pmu.c
@@ -313,7 +313,7 @@ void sbi_pmu_ovf_irq()
 	 * on an irq being triggered
 	 */
 	csr_clear(CSR_MIE, sbi_pmu_irq_mask());
-	sbi_sse_inject_event(SBI_SSE_EVENT_LOCAL_PMU);
+	sbi_sse_inject_event(SBI_SSE_EVENT_LOCAL_PMU_OVERFLOW);
 }
 
 static int pmu_ctr_enable_irq_hw(int ctr_idx)
@@ -1166,7 +1166,7 @@ int sbi_pmu_init(struct sbi_scratch *scratch, bool cold_boot)
 		total_ctrs = num_hw_ctrs + SBI_PMU_FW_CTR_MAX;
 
 		if (sbi_pmu_irq_bit() >= 0)
-			sbi_sse_add_event(SBI_SSE_EVENT_LOCAL_PMU, &pmu_sse_cb_ops);
+			sbi_sse_add_event(SBI_SSE_EVENT_LOCAL_PMU_OVERFLOW, &pmu_sse_cb_ops);
 	}
 
 	phs = pmu_get_hart_state_ptr(scratch);
diff --git a/lib/sbi/sbi_sse.c b/lib/sbi/sbi_sse.c
index 2f9bdef8..4722ddc4 100644
--- a/lib/sbi/sbi_sse.c
+++ b/lib/sbi/sbi_sse.c
@@ -195,10 +195,12 @@ static SBI_SLIST_HEAD(supported_events, sse_event_info) =
  * events in order to return SBI_ERR_NOT_SUPPORTED for them.
  */
 static const uint32_t standard_events[] = {
-	SBI_SSE_EVENT_LOCAL_RAS,
+	SBI_SSE_EVENT_LOCAL_HIGH_PRIO_RAS,
 	SBI_SSE_EVENT_LOCAL_DOUBLE_TRAP,
-	SBI_SSE_EVENT_GLOBAL_RAS,
-	SBI_SSE_EVENT_LOCAL_PMU,
+	SBI_SSE_EVENT_GLOBAL_HIGH_PRIO_RAS,
+	SBI_SSE_EVENT_LOCAL_PMU_OVERFLOW,
+	SBI_SSE_EVENT_LOCAL_LOW_PRIO_RAS,
+	SBI_SSE_EVENT_GLOBAL_LOW_PRIO_RAS,
 	SBI_SSE_EVENT_LOCAL_SOFTWARE,
 	SBI_SSE_EVENT_GLOBAL_SOFTWARE,
 };
-- 
2.47.2

[PATCH 2/6] lib: sbi: sse: Fix format string for event invalid state

[Clément Léger]

Add a missing newline and modify the display value of the event id to
use hex representation.

Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>
---
 lib/sbi/sbi_sse.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/sbi/sbi_sse.c b/lib/sbi/sbi_sse.c
index 4722ddc4..a30fad54 100644
--- a/lib/sbi/sbi_sse.c
+++ b/lib/sbi/sbi_sse.c
@@ -1268,7 +1268,7 @@ void sbi_sse_exit(struct sbi_scratch *scratch)
 			goto skip;
 
 		if (sse_event_state(e) > SBI_SSE_STATE_REGISTERED) {
-			sbi_printf("Event %d in invalid state at exit",
+			sbi_printf("Event 0x%x in invalid state at exit\n",
 				   info->event_id);
 			sse_event_set_state(e, SBI_SSE_STATE_UNUSED);
 		}
-- 
2.47.2

[PATCH 3/6] lib: sbi: sse: Return SBI_EDENIED for read only parameters.

[Clément Léger]

The SSE specification did specified that read only parameters should
return SBI_EBADRANGE but was modified recently to return SBI_EDENIED.

Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>
---
 lib/sbi/sbi_sse.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/sbi/sbi_sse.c b/lib/sbi/sbi_sse.c
index a30fad54..ac714b8a 100644
--- a/lib/sbi/sbi_sse.c
+++ b/lib/sbi/sbi_sse.c
@@ -388,7 +388,7 @@ static int sse_event_set_hart_id_check(struct sbi_sse_event *e,
 	struct sbi_domain *hd = sbi_domain_thishart_ptr();
 
 	if (!sse_event_is_global(e))
-		return SBI_EBAD_RANGE;
+		return SBI_EDENIED;
 
 	if (!sbi_domain_is_assigned_hart(hd, sbi_hartid_to_hartindex(hartid)))
 		return SBI_EINVAL;
@@ -444,7 +444,7 @@ static int sse_event_set_attr_check(struct sbi_sse_event *e, uint32_t attr_id,
 
 		return SBI_OK;
 	default:
-		return SBI_EBAD_RANGE;
+		return SBI_EDENIED;
 	}
 }
 
-- 
2.47.2

[PATCH 4/6] lib: sbi: sse: Rename STATUS* interrupted flags to SSTATUS*

[Clément Léger]

As raised by Andrew on the kvm-unit-test review, this flags are meant to
hold SSTATUS bits in the specification. Rename them to match that.

Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>
---
 include/sbi/sbi_ecall_interface.h |  4 ++--
 lib/sbi/sbi_sse.c                 | 12 ++++++------
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/include/sbi/sbi_ecall_interface.h b/include/sbi/sbi_ecall_interface.h
index bd694aa8..51e42eed 100644
--- a/include/sbi/sbi_ecall_interface.h
+++ b/include/sbi/sbi_ecall_interface.h
@@ -380,8 +380,8 @@ enum sbi_sse_attr_id {
 
 #define SBI_SSE_ATTR_CONFIG_ONESHOT	(1 << 0)
 
-#define SBI_SSE_ATTR_INTERRUPTED_FLAGS_STATUS_SPP	BIT(0)
-#define SBI_SSE_ATTR_INTERRUPTED_FLAGS_STATUS_SPIE	BIT(1)
+#define SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPP	BIT(0)
+#define SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPIE	BIT(1)
 #define SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPV	BIT(2)
 #define SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPVP	BIT(3)
 
diff --git a/lib/sbi/sbi_sse.c b/lib/sbi/sbi_sse.c
index ac714b8a..fb7ccf05 100644
--- a/lib/sbi/sbi_sse.c
+++ b/lib/sbi/sbi_sse.c
@@ -427,8 +427,8 @@ static int sse_event_set_attr_check(struct sbi_sse_event *e, uint32_t attr_id,
 
 		return sse_event_set_hart_id_check(e, val);
 	case SBI_SSE_ATTR_INTERRUPTED_FLAGS:
-		if (val & ~(SBI_SSE_ATTR_INTERRUPTED_FLAGS_STATUS_SPP |
-			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_STATUS_SPIE |
+		if (val & ~(SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPP |
+			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPIE |
 			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPV |
 			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPVP))
 			return SBI_EINVAL;
@@ -513,9 +513,9 @@ static unsigned long sse_interrupted_flags(unsigned long mstatus)
 	unsigned long hstatus, flags = 0;
 
 	if (mstatus & (MSTATUS_SPIE))
-		flags |= SBI_SSE_ATTR_INTERRUPTED_FLAGS_STATUS_SPIE;
+		flags |= SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPIE;
 	if (mstatus & (MSTATUS_SPP))
-		flags |= SBI_SSE_ATTR_INTERRUPTED_FLAGS_STATUS_SPP;
+		flags |= SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPP;
 
 	if (misa_extension('H')) {
 		hstatus = csr_read(CSR_HSTATUS);
@@ -626,11 +626,11 @@ static void sse_event_resume(struct sbi_sse_event *e,
 		regs->mstatus |= MSTATUS_SIE;
 
 	regs->mstatus &= ~MSTATUS_SPIE;
-	if (i_ctx->flags & SBI_SSE_ATTR_INTERRUPTED_FLAGS_STATUS_SPIE)
+	if (i_ctx->flags & SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPIE)
 		regs->mstatus |= MSTATUS_SPIE;
 
 	regs->mstatus &= ~MSTATUS_SPP;
-	if (i_ctx->flags & SBI_SSE_ATTR_INTERRUPTED_FLAGS_STATUS_SPP)
+	if (i_ctx->flags & SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPP)
 		regs->mstatus |= MSTATUS_SPP;
 
 	regs->a7 = i_ctx->a7;
-- 
2.47.2

[PATCH 5/6] lib: sbi: sse: Add support for SSTATUS.SPELP

[Clément Léger]

As raised during the ARC review, SPELP was not handled during the event
injection process. Save it as part of the interrupted flags, clear it
before injecting the event and restore it after completion.

Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>
---
 include/sbi/sbi_ecall_interface.h |  1 +
 lib/sbi/sbi_sse.c                 | 16 +++++++++++++---
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/include/sbi/sbi_ecall_interface.h b/include/sbi/sbi_ecall_interface.h
index 51e42eed..a93e61fa 100644
--- a/include/sbi/sbi_ecall_interface.h
+++ b/include/sbi/sbi_ecall_interface.h
@@ -384,6 +384,7 @@ enum sbi_sse_attr_id {
 #define SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPIE	BIT(1)
 #define SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPV	BIT(2)
 #define SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPVP	BIT(3)
+#define SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPELP	BIT(4)
 
 enum sbi_sse_state {
 	SBI_SSE_STATE_UNUSED		= 0,
diff --git a/lib/sbi/sbi_sse.c b/lib/sbi/sbi_sse.c
index fb7ccf05..a45d3eeb 100644
--- a/lib/sbi/sbi_sse.c
+++ b/lib/sbi/sbi_sse.c
@@ -430,7 +430,8 @@ static int sse_event_set_attr_check(struct sbi_sse_event *e, uint32_t attr_id,
 		if (val & ~(SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPP |
 			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPIE |
 			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPV |
-			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPVP))
+			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPVP |
+			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPELP))
 			return SBI_EINVAL;
 		__attribute__((__fallthrough__));
 	case SBI_SSE_ATTR_INTERRUPTED_SEPC:
@@ -516,6 +517,8 @@ static unsigned long sse_interrupted_flags(unsigned long mstatus)
 		flags |= SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPIE;
 	if (mstatus & (MSTATUS_SPP))
 		flags |= SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPP;
+	if (mstatus & (MSTATUS_SPELP))
+		flags |= SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPELP;
 
 	if (misa_extension('H')) {
 		hstatus = csr_read(CSR_HSTATUS);
@@ -573,8 +576,11 @@ static void sse_event_inject(struct sbi_sse_event *e,
 	regs->a7 = e->attrs.entry.arg;
 	regs->mepc = e->attrs.entry.pc;
 
-	/* Return to S-mode with virtualization disabled */
-	regs->mstatus &= ~(MSTATUS_MPP | MSTATUS_SIE);
+	/*
+	 * Return to S-mode with virtualization disabled, no expected landing
+	 * pad.
+	 */
+	regs->mstatus &= ~(MSTATUS_MPP | MSTATUS_SIE | MSTATUS_SPELP);
 	regs->mstatus |= (PRV_S << MSTATUS_MPP_SHIFT);
 
 #if __riscv_xlen == 64
@@ -633,6 +639,10 @@ static void sse_event_resume(struct sbi_sse_event *e,
 	if (i_ctx->flags & SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPP)
 		regs->mstatus |= MSTATUS_SPP;
 
+	regs->mstatus &= ~MSTATUS_SPELP;
+	if (i_ctx->flags & SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPELP)
+		regs->mstatus |= MSTATUS_SPELP;
+
 	regs->a7 = i_ctx->a7;
 	regs->a6 = i_ctx->a6;
 	csr_write(CSR_SEPC, i_ctx->sepc);
-- 
2.47.2

[PATCH 6/6] lib: sbi: sse: Add support for SSTATUS.SDT

[Clément Léger]

Similarly to what is done for SPELP, handle SSTATUS.SDT upon event
injection. In order to mimick an interrupt, set SDT to 1 for injection and
save its previous value in interrupted_flags[5:5]. Restore it upon
completion.

Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>
---
 include/sbi/riscv_encoding.h      |  3 ++-
 include/sbi/sbi_ecall_interface.h |  1 +
 lib/sbi/sbi_sse.c                 | 12 ++++++++++--
 3 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/include/sbi/riscv_encoding.h b/include/sbi/riscv_encoding.h
index 03c68a57..84d3c17b 100644
--- a/include/sbi/riscv_encoding.h
+++ b/include/sbi/riscv_encoding.h
@@ -32,7 +32,8 @@
 #define MSTATUS_TVM			_UL(0x00100000)
 #define MSTATUS_TW			_UL(0x00200000)
 #define MSTATUS_TSR			_UL(0x00400000)
-#define MSTATUS_SPELP		_UL(0x00800000)
+#define MSTATUS_SPELP			_UL(0x00800000)
+#define MSTATUS_SDT			_UL(0x01000000)
 #define MSTATUS32_SD			_UL(0x80000000)
 #if __riscv_xlen == 64
 #define MSTATUS_UXL			_ULL(0x0000000300000000)
diff --git a/include/sbi/sbi_ecall_interface.h b/include/sbi/sbi_ecall_interface.h
index a93e61fa..3d8bbcf3 100644
--- a/include/sbi/sbi_ecall_interface.h
+++ b/include/sbi/sbi_ecall_interface.h
@@ -385,6 +385,7 @@ enum sbi_sse_attr_id {
 #define SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPV	BIT(2)
 #define SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPVP	BIT(3)
 #define SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPELP	BIT(4)
+#define SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SDT	BIT(5)
 
 enum sbi_sse_state {
 	SBI_SSE_STATE_UNUSED		= 0,
diff --git a/lib/sbi/sbi_sse.c b/lib/sbi/sbi_sse.c
index a45d3eeb..79c5bdb4 100644
--- a/lib/sbi/sbi_sse.c
+++ b/lib/sbi/sbi_sse.c
@@ -431,7 +431,8 @@ static int sse_event_set_attr_check(struct sbi_sse_event *e, uint32_t attr_id,
 			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPIE |
 			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPV |
 			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPVP |
-			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPELP))
+			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPELP |
+			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SDT))
 			return SBI_EINVAL;
 		__attribute__((__fallthrough__));
 	case SBI_SSE_ATTR_INTERRUPTED_SEPC:
@@ -519,6 +520,8 @@ static unsigned long sse_interrupted_flags(unsigned long mstatus)
 		flags |= SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPP;
 	if (mstatus & (MSTATUS_SPELP))
 		flags |= SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPELP;
+	if (mstatus & (MSTATUS_SDT))
+		flags |= SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SDT;
 
 	if (misa_extension('H')) {
 		hstatus = csr_read(CSR_HSTATUS);
@@ -578,10 +581,11 @@ static void sse_event_inject(struct sbi_sse_event *e,
 
 	/*
 	 * Return to S-mode with virtualization disabled, no expected landing
-	 * pad.
+	 * pad, supervisor trap disabled.
 	 */
 	regs->mstatus &= ~(MSTATUS_MPP | MSTATUS_SIE | MSTATUS_SPELP);
 	regs->mstatus |= (PRV_S << MSTATUS_MPP_SHIFT);
+	regs->mstatus |= MSTATUS_SDT;
 
 #if __riscv_xlen == 64
 	regs->mstatus &= ~MSTATUS_MPV;
@@ -643,6 +647,10 @@ static void sse_event_resume(struct sbi_sse_event *e,
 	if (i_ctx->flags & SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPELP)
 		regs->mstatus |= MSTATUS_SPELP;
 
+	regs->mstatus &= ~MSTATUS_SDT;
+	if (i_ctx->flags & SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SDT)
+		regs->mstatus |= MSTATUS_SDT;
+
 	regs->a7 = i_ctx->a7;
 	regs->a6 = i_ctx->a6;
 	csr_write(CSR_SEPC, i_ctx->sepc);
-- 
2.47.2

[PATCH 1/6] lib: sbi: sse: Update SSE event ids

[Andrew Jones]

On Mon, Mar 17, 2025 at 11:54:19AM +0100, Cl?ment L?ger wrote:
> The latest specification added new high priority RAS events and renamed
> the PMU to PMU_OVERFLOW.
> 
> Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>
> ---
>  include/sbi/sbi_ecall_interface.h | 44 ++++++++++++++++++++++++-------
>  lib/sbi/sbi_pmu.c                 |  4 +--
>  lib/sbi/sbi_sse.c                 |  8 +++---
>  3 files changed, 42 insertions(+), 14 deletions(-)
>

Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

[PATCH 2/6] lib: sbi: sse: Fix format string for event invalid state

[Andrew Jones]

On Mon, Mar 17, 2025 at 11:54:20AM +0100, Cl?ment L?ger wrote:
> Add a missing newline and modify the display value of the event id to
> use hex representation.
> 
> Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>
> ---
>  lib/sbi/sbi_sse.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/lib/sbi/sbi_sse.c b/lib/sbi/sbi_sse.c
> index 4722ddc4..a30fad54 100644
> --- a/lib/sbi/sbi_sse.c
> +++ b/lib/sbi/sbi_sse.c
> @@ -1268,7 +1268,7 @@ void sbi_sse_exit(struct sbi_scratch *scratch)
>  			goto skip;
>  
>  		if (sse_event_state(e) > SBI_SSE_STATE_REGISTERED) {
> -			sbi_printf("Event %d in invalid state at exit",
> +			sbi_printf("Event 0x%x in invalid state at exit\n",
>  				   info->event_id);
>  			sse_event_set_state(e, SBI_SSE_STATE_UNUSED);
>  		}
> -- 
> 2.47.2
>

I'm not sure we want the print statement, but if we do, then

Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

[PATCH 2/6] lib: sbi: sse: Fix format string for event invalid state

[Clément Léger]

On 24/03/2025 17:39, Andrew Jones wrote:
> On Mon, Mar 17, 2025 at 11:54:20AM +0100, Cl?ment L?ger wrote:
>> Add a missing newline and modify the display value of the event id to
>> use hex representation.
>>
>> Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>
>> ---
>>  lib/sbi/sbi_sse.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/lib/sbi/sbi_sse.c b/lib/sbi/sbi_sse.c
>> index 4722ddc4..a30fad54 100644
>> --- a/lib/sbi/sbi_sse.c
>> +++ b/lib/sbi/sbi_sse.c
>> @@ -1268,7 +1268,7 @@ void sbi_sse_exit(struct sbi_scratch *scratch)
>>  			goto skip;
>>  
>>  		if (sse_event_state(e) > SBI_SSE_STATE_REGISTERED) {
>> -			sbi_printf("Event %d in invalid state at exit",
>> +			sbi_printf("Event 0x%x in invalid state at exit\n",
>>  				   info->event_id);
>>  			sse_event_set_state(e, SBI_SSE_STATE_UNUSED);
>>  		}
>> -- 
>> 2.47.2
>>
> 
> I'm not sure we want the print statement, but if we do, then

Agreed, that's actually debug so that should probably be removed and
handled gracefully.

Thanks,

Cl?ment

> 
> Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

[PATCH 3/6] lib: sbi: sse: Return SBI_EDENIED for read only parameters.

[Andrew Jones]

On Mon, Mar 17, 2025 at 11:54:21AM +0100, Cl?ment L?ger wrote:
> The SSE specification did specified that read only parameters should
> return SBI_EBADRANGE but was modified recently to return SBI_EDENIED.
> 
> Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>
> ---
>  lib/sbi/sbi_sse.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/lib/sbi/sbi_sse.c b/lib/sbi/sbi_sse.c
> index a30fad54..ac714b8a 100644
> --- a/lib/sbi/sbi_sse.c
> +++ b/lib/sbi/sbi_sse.c
> @@ -388,7 +388,7 @@ static int sse_event_set_hart_id_check(struct sbi_sse_event *e,
>  	struct sbi_domain *hd = sbi_domain_thishart_ptr();
>  
>  	if (!sse_event_is_global(e))
> -		return SBI_EBAD_RANGE;
> +		return SBI_EDENIED;
>  
>  	if (!sbi_domain_is_assigned_hart(hd, sbi_hartid_to_hartindex(hartid)))
>  		return SBI_EINVAL;
> @@ -444,7 +444,7 @@ static int sse_event_set_attr_check(struct sbi_sse_event *e, uint32_t attr_id,
>  
>  		return SBI_OK;
>  	default:
> -		return SBI_EBAD_RANGE;
> +		return SBI_EDENIED;

This confused me at first. Maybe a comment pointing out that
sbi_sse_attr_check() already confirmed we're in range and
this switch default just catches read-only attributes would
be helpful.

Otherwise,

Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

Thanks,
drew

>  	}
>  }
>  
> -- 
> 2.47.2
> 

[PATCH 3/6] lib: sbi: sse: Return SBI_EDENIED for read only parameters.

[Clément Léger]

On 24/03/2025 18:01, Andrew Jones wrote:
> On Mon, Mar 17, 2025 at 11:54:21AM +0100, Cl?ment L?ger wrote:
>> The SSE specification did specified that read only parameters should
>> return SBI_EBADRANGE but was modified recently to return SBI_EDENIED.
>>
>> Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>
>> ---
>>  lib/sbi/sbi_sse.c | 4 ++--
>>  1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/lib/sbi/sbi_sse.c b/lib/sbi/sbi_sse.c
>> index a30fad54..ac714b8a 100644
>> --- a/lib/sbi/sbi_sse.c
>> +++ b/lib/sbi/sbi_sse.c
>> @@ -388,7 +388,7 @@ static int sse_event_set_hart_id_check(struct sbi_sse_event *e,
>>  	struct sbi_domain *hd = sbi_domain_thishart_ptr();
>>  
>>  	if (!sse_event_is_global(e))
>> -		return SBI_EBAD_RANGE;
>> +		return SBI_EDENIED;
>>  
>>  	if (!sbi_domain_is_assigned_hart(hd, sbi_hartid_to_hartindex(hartid)))
>>  		return SBI_EINVAL;
>> @@ -444,7 +444,7 @@ static int sse_event_set_attr_check(struct sbi_sse_event *e, uint32_t attr_id,
>>  
>>  		return SBI_OK;
>>  	default:
>> -		return SBI_EBAD_RANGE;
>> +		return SBI_EDENIED;
> 
> This confused me at first. Maybe a comment pointing out that
> sbi_sse_attr_check() already confirmed we're in range and
> this switch default just catches read-only attributes would
> be helpful.

Yes sure, I'll do that in the next version.

Thanks,

Cl?ment

> 
> Otherwise,
> 
> Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
> 
> Thanks,
> drew
> 
>>  	}
>>  }
>>  
>> -- 
>> 2.47.2
>>

[PATCH 4/6] lib: sbi: sse: Rename STATUS* interrupted flags to SSTATUS*

[Andrew Jones]

On Mon, Mar 17, 2025 at 11:54:22AM +0100, Cl?ment L?ger wrote:
> As raised by Andrew on the kvm-unit-test review, this flags are meant to
> hold SSTATUS bits in the specification. Rename them to match that.
> 
> Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>
> ---
>  include/sbi/sbi_ecall_interface.h |  4 ++--
>  lib/sbi/sbi_sse.c                 | 12 ++++++------
>  2 files changed, 8 insertions(+), 8 deletions(-)
> 
> diff --git a/include/sbi/sbi_ecall_interface.h b/include/sbi/sbi_ecall_interface.h
> index bd694aa8..51e42eed 100644
> --- a/include/sbi/sbi_ecall_interface.h
> +++ b/include/sbi/sbi_ecall_interface.h
> @@ -380,8 +380,8 @@ enum sbi_sse_attr_id {
>  
>  #define SBI_SSE_ATTR_CONFIG_ONESHOT	(1 << 0)
>  
> -#define SBI_SSE_ATTR_INTERRUPTED_FLAGS_STATUS_SPP	BIT(0)
> -#define SBI_SSE_ATTR_INTERRUPTED_FLAGS_STATUS_SPIE	BIT(1)
> +#define SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPP	BIT(0)
> +#define SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPIE	BIT(1)
>  #define SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPV	BIT(2)
>  #define SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPVP	BIT(3)
>  
> diff --git a/lib/sbi/sbi_sse.c b/lib/sbi/sbi_sse.c
> index ac714b8a..fb7ccf05 100644
> --- a/lib/sbi/sbi_sse.c
> +++ b/lib/sbi/sbi_sse.c
> @@ -427,8 +427,8 @@ static int sse_event_set_attr_check(struct sbi_sse_event *e, uint32_t attr_id,
>  
>  		return sse_event_set_hart_id_check(e, val);
>  	case SBI_SSE_ATTR_INTERRUPTED_FLAGS:
> -		if (val & ~(SBI_SSE_ATTR_INTERRUPTED_FLAGS_STATUS_SPP |
> -			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_STATUS_SPIE |
> +		if (val & ~(SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPP |
> +			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPIE |
>  			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPV |
>  			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPVP))
>  			return SBI_EINVAL;
> @@ -513,9 +513,9 @@ static unsigned long sse_interrupted_flags(unsigned long mstatus)
>  	unsigned long hstatus, flags = 0;
>  
>  	if (mstatus & (MSTATUS_SPIE))
> -		flags |= SBI_SSE_ATTR_INTERRUPTED_FLAGS_STATUS_SPIE;
> +		flags |= SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPIE;
>  	if (mstatus & (MSTATUS_SPP))
> -		flags |= SBI_SSE_ATTR_INTERRUPTED_FLAGS_STATUS_SPP;
> +		flags |= SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPP;
>  
>  	if (misa_extension('H')) {
>  		hstatus = csr_read(CSR_HSTATUS);
> @@ -626,11 +626,11 @@ static void sse_event_resume(struct sbi_sse_event *e,
>  		regs->mstatus |= MSTATUS_SIE;
>  
>  	regs->mstatus &= ~MSTATUS_SPIE;
> -	if (i_ctx->flags & SBI_SSE_ATTR_INTERRUPTED_FLAGS_STATUS_SPIE)
> +	if (i_ctx->flags & SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPIE)
>  		regs->mstatus |= MSTATUS_SPIE;
>  
>  	regs->mstatus &= ~MSTATUS_SPP;
> -	if (i_ctx->flags & SBI_SSE_ATTR_INTERRUPTED_FLAGS_STATUS_SPP)
> +	if (i_ctx->flags & SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPP)
>  		regs->mstatus |= MSTATUS_SPP;
>  
>  	regs->a7 = i_ctx->a7;
> -- 
> 2.47.2
>

Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

[PATCH 5/6] lib: sbi: sse: Add support for SSTATUS.SPELP

[Andrew Jones]

On Mon, Mar 17, 2025 at 11:54:23AM +0100, Cl?ment L?ger wrote:
> As raised during the ARC review, SPELP was not handled during the event
> injection process. Save it as part of the interrupted flags, clear it
> before injecting the event and restore it after completion.
> 
> Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>
> ---
>  include/sbi/sbi_ecall_interface.h |  1 +
>  lib/sbi/sbi_sse.c                 | 16 +++++++++++++---
>  2 files changed, 14 insertions(+), 3 deletions(-)
> 
> diff --git a/include/sbi/sbi_ecall_interface.h b/include/sbi/sbi_ecall_interface.h
> index 51e42eed..a93e61fa 100644
> --- a/include/sbi/sbi_ecall_interface.h
> +++ b/include/sbi/sbi_ecall_interface.h
> @@ -384,6 +384,7 @@ enum sbi_sse_attr_id {
>  #define SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPIE	BIT(1)
>  #define SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPV	BIT(2)
>  #define SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPVP	BIT(3)
> +#define SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPELP	BIT(4)
>  
>  enum sbi_sse_state {
>  	SBI_SSE_STATE_UNUSED		= 0,
> diff --git a/lib/sbi/sbi_sse.c b/lib/sbi/sbi_sse.c
> index fb7ccf05..a45d3eeb 100644
> --- a/lib/sbi/sbi_sse.c
> +++ b/lib/sbi/sbi_sse.c
> @@ -430,7 +430,8 @@ static int sse_event_set_attr_check(struct sbi_sse_event *e, uint32_t attr_id,
>  		if (val & ~(SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPP |
>  			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPIE |
>  			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPV |
> -			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPVP))
> +			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPVP |
> +			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPELP))
>  			return SBI_EINVAL;
>  		__attribute__((__fallthrough__));
>  	case SBI_SSE_ATTR_INTERRUPTED_SEPC:
> @@ -516,6 +517,8 @@ static unsigned long sse_interrupted_flags(unsigned long mstatus)
>  		flags |= SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPIE;
>  	if (mstatus & (MSTATUS_SPP))
>  		flags |= SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPP;
> +	if (mstatus & (MSTATUS_SPELP))
> +		flags |= SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPELP;

Not sure why we have the superfluous (), but I guess this is consistent.

>  
>  	if (misa_extension('H')) {
>  		hstatus = csr_read(CSR_HSTATUS);
> @@ -573,8 +576,11 @@ static void sse_event_inject(struct sbi_sse_event *e,
>  	regs->a7 = e->attrs.entry.arg;
>  	regs->mepc = e->attrs.entry.pc;
>  
> -	/* Return to S-mode with virtualization disabled */
> -	regs->mstatus &= ~(MSTATUS_MPP | MSTATUS_SIE);
> +	/*
> +	 * Return to S-mode with virtualization disabled, no expected landing

s/no/not/

> +	 * pad.
> +	 */
> +	regs->mstatus &= ~(MSTATUS_MPP | MSTATUS_SIE | MSTATUS_SPELP);
>  	regs->mstatus |= (PRV_S << MSTATUS_MPP_SHIFT);
>  
>  #if __riscv_xlen == 64
> @@ -633,6 +639,10 @@ static void sse_event_resume(struct sbi_sse_event *e,
>  	if (i_ctx->flags & SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPP)
>  		regs->mstatus |= MSTATUS_SPP;
>  
> +	regs->mstatus &= ~MSTATUS_SPELP;
> +	if (i_ctx->flags & SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPELP)
> +		regs->mstatus |= MSTATUS_SPELP;
> +
>  	regs->a7 = i_ctx->a7;
>  	regs->a6 = i_ctx->a6;
>  	csr_write(CSR_SEPC, i_ctx->sepc);
> -- 
> 2.47.2
>

Otherwise,

Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

[PATCH 6/6] lib: sbi: sse: Add support for SSTATUS.SDT

[Andrew Jones]

On Mon, Mar 17, 2025 at 11:54:24AM +0100, Cl?ment L?ger wrote:
> Similarly to what is done for SPELP, handle SSTATUS.SDT upon event
> injection. In order to mimick an interrupt, set SDT to 1 for injection and
> save its previous value in interrupted_flags[5:5]. Restore it upon
> completion.
> 
> Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>
> ---
>  include/sbi/riscv_encoding.h      |  3 ++-
>  include/sbi/sbi_ecall_interface.h |  1 +
>  lib/sbi/sbi_sse.c                 | 12 ++++++++++--
>  3 files changed, 13 insertions(+), 3 deletions(-)
> 
> diff --git a/include/sbi/riscv_encoding.h b/include/sbi/riscv_encoding.h
> index 03c68a57..84d3c17b 100644
> --- a/include/sbi/riscv_encoding.h
> +++ b/include/sbi/riscv_encoding.h
> @@ -32,7 +32,8 @@
>  #define MSTATUS_TVM			_UL(0x00100000)
>  #define MSTATUS_TW			_UL(0x00200000)
>  #define MSTATUS_TSR			_UL(0x00400000)
> -#define MSTATUS_SPELP		_UL(0x00800000)
> +#define MSTATUS_SPELP			_UL(0x00800000)
> +#define MSTATUS_SDT			_UL(0x01000000)
>  #define MSTATUS32_SD			_UL(0x80000000)
>  #if __riscv_xlen == 64
>  #define MSTATUS_UXL			_ULL(0x0000000300000000)
> diff --git a/include/sbi/sbi_ecall_interface.h b/include/sbi/sbi_ecall_interface.h
> index a93e61fa..3d8bbcf3 100644
> --- a/include/sbi/sbi_ecall_interface.h
> +++ b/include/sbi/sbi_ecall_interface.h
> @@ -385,6 +385,7 @@ enum sbi_sse_attr_id {
>  #define SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPV	BIT(2)
>  #define SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPVP	BIT(3)
>  #define SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPELP	BIT(4)
> +#define SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SDT	BIT(5)
>  
>  enum sbi_sse_state {
>  	SBI_SSE_STATE_UNUSED		= 0,
> diff --git a/lib/sbi/sbi_sse.c b/lib/sbi/sbi_sse.c
> index a45d3eeb..79c5bdb4 100644
> --- a/lib/sbi/sbi_sse.c
> +++ b/lib/sbi/sbi_sse.c
> @@ -431,7 +431,8 @@ static int sse_event_set_attr_check(struct sbi_sse_event *e, uint32_t attr_id,
>  			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPIE |
>  			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPV |
>  			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_HSTATUS_SPVP |
> -			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPELP))
> +			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPELP |
> +			    SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SDT))
>  			return SBI_EINVAL;
>  		__attribute__((__fallthrough__));
>  	case SBI_SSE_ATTR_INTERRUPTED_SEPC:
> @@ -519,6 +520,8 @@ static unsigned long sse_interrupted_flags(unsigned long mstatus)
>  		flags |= SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPP;
>  	if (mstatus & (MSTATUS_SPELP))
>  		flags |= SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPELP;
> +	if (mstatus & (MSTATUS_SDT))
> +		flags |= SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SDT;
>  
>  	if (misa_extension('H')) {
>  		hstatus = csr_read(CSR_HSTATUS);
> @@ -578,10 +581,11 @@ static void sse_event_inject(struct sbi_sse_event *e,
>  
>  	/*
>  	 * Return to S-mode with virtualization disabled, no expected landing
> -	 * pad.
> +	 * pad, supervisor trap disabled.
>  	 */
>  	regs->mstatus &= ~(MSTATUS_MPP | MSTATUS_SIE | MSTATUS_SPELP);
>  	regs->mstatus |= (PRV_S << MSTATUS_MPP_SHIFT);
> +	regs->mstatus |= MSTATUS_SDT;
>  
>  #if __riscv_xlen == 64
>  	regs->mstatus &= ~MSTATUS_MPV;
> @@ -643,6 +647,10 @@ static void sse_event_resume(struct sbi_sse_event *e,
>  	if (i_ctx->flags & SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SPELP)
>  		regs->mstatus |= MSTATUS_SPELP;
>  
> +	regs->mstatus &= ~MSTATUS_SDT;
> +	if (i_ctx->flags & SBI_SSE_ATTR_INTERRUPTED_FLAGS_SSTATUS_SDT)
> +		regs->mstatus |= MSTATUS_SDT;
> +
>  	regs->a7 = i_ctx->a7;
>  	regs->a6 = i_ctx->a6;
>  	csr_write(CSR_SEPC, i_ctx->sepc);
> -- 
> 2.47.2
>

Reviewed-by: Andrew Jones <ajones@ventanamicro.com>