[RFC PATCH v2 1/3] riscv: add SBI SSE extension definitions

[Clément Léger]

Add needed definitions for SBI Supervisor Software Events extension [1].
This extension enables the SBI to inject events into supervisor software
much like ARM SDEI.

[1] https://lists.riscv.org/g/tech-prs/message/515

Signed-off-by: Clément Léger <cleger@xxxxxxxxxxxx>
---
 arch/riscv/include/asm/sbi.h | 47 ++++++++++++++++++++++++++++++++++++
 arch/riscv/kernel/sbi.c      |  4 +++
 2 files changed, 51 insertions(+)

diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
index 0892f4421bc4..11cad3ec4a18 100644
--- a/arch/riscv/include/asm/sbi.h
+++ b/arch/riscv/include/asm/sbi.h
@@ -31,6 +31,7 @@ enum sbi_ext_id {
 	SBI_EXT_SRST = 0x53525354,
 	SBI_EXT_PMU = 0x504D55,
 	SBI_EXT_DBCN = 0x4442434E,
+	SBI_EXT_SSE = 0x535345,
 
 	/* Experimentals extensions must lie within this range */
 	SBI_EXT_EXPERIMENTAL_START = 0x08000000,
@@ -243,6 +244,49 @@ enum sbi_ext_dbcn_fid {
 	SBI_EXT_DBCN_CONSOLE_WRITE_BYTE = 2,
 };
 
+enum sbi_ext_sse_fid {
+	SBI_SSE_EVENT_ATTR_READ = 0,
+	SBI_SSE_EVENT_ATTR_WRITE,
+	SBI_SSE_EVENT_REGISTER,
+	SBI_SSE_EVENT_UNREGISTER,
+	SBI_SSE_EVENT_ENABLE,
+	SBI_SSE_EVENT_DISABLE,
+	SBI_SSE_EVENT_COMPLETE,
+	SBI_SSE_EVENT_SIGNAL,
+};
+
+enum sbi_sse_event_attr {
+	SBI_SSE_ATTR_STATUS = 0,
+	SBI_SSE_ATTR_PRIO,
+	SBI_SSE_ATTR_CONFIG,
+	SBI_SSE_ATTR_PREFERRED_HART,
+	SBI_SSE_ATTR_ENTRY_PC,
+	SBI_SSE_ATTR_ENTRY_A0,
+	SBI_SSE_ATTR_ENTRY_A6,
+	SBI_SSE_ATTR_ENTRY_A7,
+	SBI_SSE_ATTR_INTERRUPTED_MODE,
+	SBI_SSE_ATTR_INTERRUPTED_PC,
+	SBI_SSE_ATTR_INTERRUPTED_A0,
+	SBI_SSE_ATTR_INTERRUPTED_A6,
+	SBI_SSE_ATTR_INTERRUPTED_A7,
+};
+
+#define SBI_SSE_ATTR_STATUS_STATE_OFFSET	0
+#define SBI_SSE_ATTR_STATUS_STATE_MASK		0x3
+#define SBI_SSE_ATTR_STATUS_PENDING_OFFSET	2
+#define SBI_SSE_ATTR_STATUS_INJECT_OFFSET	3
+
+#define SBI_SSE_ATTR_CONFIG_ONESHOT	(1 << 0)
+
+#define SBI_SSE_EVENT_LOCAL_RAS		0x00000000
+#define SBI_SSE_EVENT_GLOBAL_RAS	0x00008000
+#define SBI_SSE_EVENT_LOCAL_PMU		0x00010000
+#define SBI_SSE_EVENT_LOCAL_SOFTWARE	0xffff0000
+#define SBI_SSE_EVENT_GLOBAL_SOFTWARE	0xffff8000
+
+#define SBI_SSE_EVENT_GLOBAL		(1 << 15)
+#define SBI_SSE_EVENT_PLATFORM		(1 << 14)
+
 #define SBI_SPEC_VERSION_DEFAULT	0x1
 #define SBI_SPEC_VERSION_MAJOR_SHIFT	24
 #define SBI_SPEC_VERSION_MAJOR_MASK	0x7f
@@ -258,6 +302,9 @@ enum sbi_ext_dbcn_fid {
 #define SBI_ERR_ALREADY_AVAILABLE -6
 #define SBI_ERR_ALREADY_STARTED -7
 #define SBI_ERR_ALREADY_STOPPED -8
+#define SBI_ERR_INVALID_STATE	-10
+#define SBI_ERR_BAD_RANGE	-11
+#define SBI_ERR_BUSY		-12
 
 extern unsigned long sbi_spec_version;
 struct sbiret {
diff --git a/arch/riscv/kernel/sbi.c b/arch/riscv/kernel/sbi.c
index 5a62ed1da453..cfd8d51fa2a9 100644
--- a/arch/riscv/kernel/sbi.c
+++ b/arch/riscv/kernel/sbi.c
@@ -57,9 +57,13 @@ int sbi_err_map_linux_errno(int err)
 	case SBI_ERR_DENIED:
 		return -EPERM;
 	case SBI_ERR_INVALID_PARAM:
+	case SBI_ERR_BAD_RANGE:
+	case SBI_ERR_INVALID_STATE:
 		return -EINVAL;
 	case SBI_ERR_INVALID_ADDRESS:
 		return -EFAULT;
+	case SBI_ERR_BUSY:
+		return -EBUSY;
 	case SBI_ERR_NOT_SUPPORTED:
 	case SBI_ERR_FAILURE:
 	default:
-- 
2.43.0