[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: Clément Léger <cleger at 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