include: sbi: Introduce nascent_init() platform callback

We introduce nascent_init() platform callback which will allow
platforms to do very early initialization of platform specific
per-HART CSRs and per-HART devices.

Signed-off-by: Anup Patel <[email protected]>
Signed-off-by: Anup Patel <[email protected]>
Reviewed-by: Atish Patra <[email protected]>

1 files changed, 20 insertions, 0 deletions

diff --git a/include/sbi/sbi_platform.h b/include/sbi/sbi_platform.h
index 4d192f2a..0b5ae4be 100644
--- a/include/sbi/sbi_platform.h
+++ b/include/sbi/sbi_platform.h
@@ -64,6 +64,9 @@ enum sbi_platform_features {
 
 /** Platform functions */
 struct sbi_platform_operations {
+	/* Platform nascent initialization */
+	int (*nascent_init)(void);
+
 	/** Platform early initialization */
 	int (*early_init)(bool cold_boot);
 	/** Platform final initialization */
@@ -300,6 +303,23 @@ static inline bool sbi_platform_hart_invalid(const struct sbi_platform *plat,
 }
 
 /**
+ * Nascent (very early) initialization for current HART
+ *
+ * NOTE: This function can be used to do very early initialization of
+ * platform specific per-HART CSRs and devices.
+ *
+ * @param plat pointer to struct sbi_platform
+ *
+ * @return 0 on success and negative error code on failure
+ */
+static inline int sbi_platform_nascent_init(const struct sbi_platform *plat)
+{
+	if (plat && sbi_platform_ops(plat)->nascent_init)
+		return sbi_platform_ops(plat)->nascent_init();
+	return 0;
+}
+
+/**
  * Early initialization for current HART
  *
  * @param plat pointer to struct sbi_platform