[PATCH v2 2/3] lib: sbi: report smrnmi_handlers_init failures instead of ignoring them

[Nia Su]

smrnmi_handlers_init returned void, so a failed callback went
unreported and NMIE was enabled anyway.

Change it to return int and skip enabling NMIE on failure.

Signed-off-by: Nylon Chen <nylon.chen at sifive.com>
Co-developed-by: Nia Su <nia.su at sifive.com>
Signed-off-by: Nia Su <nia.su at sifive.com>
---
 include/sbi/sbi_platform.h |  2 +-
 lib/sbi/sbi_hart.c         | 19 ++++++++++++-------
 2 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/include/sbi/sbi_platform.h b/include/sbi/sbi_platform.h
index 1e9a23c1252558879c683633ad000828fbfa8f3f..d55805defafb0a7935d0d95653aefcc622078f69 100644
--- a/include/sbi/sbi_platform.h
+++ b/include/sbi/sbi_platform.h
@@ -155,7 +155,7 @@ struct sbi_platform_operations {
 	void (*pmp_disable)(unsigned int n);
 
 	/** platform specific Smrnmi handlers init on current HART */
-	void (*smrnmi_handlers_init)(void (*rnmi_handler)(void),
+	int (*smrnmi_handlers_init)(void (*rnmi_handler)(void),
 			void (*rnme_handler)(void));
 
 	/** platform specific Smrnmi NMI handler.
diff --git a/lib/sbi/sbi_hart.c b/lib/sbi/sbi_hart.c
index d2b5be6a3ce68e6ab5c368e83b9cd0f09c4ca337..e34bbe27a8396fef80a3d69c0416898cae47ec88 100644
--- a/lib/sbi/sbi_hart.c
+++ b/lib/sbi/sbi_hart.c
@@ -466,15 +466,16 @@ static int hart_mhpm_get_allowed_bits(void)
 	return num_bits;
 }
 
-static void sbi_smrnmi_hart_init(struct sbi_scratch *scratch)
+static int sbi_smrnmi_hart_init(struct sbi_scratch *scratch)
 {
 	const struct sbi_platform *plat;
 	const struct sbi_platform_operations *ops;
 	extern void _trap_rnmi_handler(void);
 	extern void _trap_handler(void);
+	int ret;
 
 	if (!sbi_hart_has_extension(scratch, SBI_HART_EXT_SMRNMI))
-		return;
+		return 0;
 
 	plat = sbi_platform_thishart_ptr();
 	ops  = sbi_platform_ops(plat);
@@ -484,13 +485,17 @@ static void sbi_smrnmi_hart_init(struct sbi_scratch *scratch)
 
 	/* Reuse _trap_handler for the RNME slot since RNME is taken
 	 * as a regular M-mode trap with NMIE=0. */
-	ops->smrnmi_handlers_init(_trap_rnmi_handler, _trap_handler);
+	ret = ops->smrnmi_handlers_init(_trap_rnmi_handler, _trap_handler);
+	if (ret)
+		return ret;
 
 	/* Initialize MNSCRATCH for the RNMI handler */
 	csr_write(CSR_MNSCRATCH, scratch);
 
 	/* Enable NMIs */
 	csr_set(CSR_MNSTATUS, MNSTATUS_NMIE);
+
+	return 0;
 }
 
 static int hart_detect_features(struct sbi_scratch *scratch, bool cold_boot)
@@ -514,7 +519,9 @@ static int hart_detect_features(struct sbi_scratch *scratch, bool cold_boot)
 	if (rc)
 		return rc;
 
-	sbi_smrnmi_hart_init(scratch);
+	rc = sbi_smrnmi_hart_init(scratch);
+	if (rc)
+		return rc;
 
 #define __check_hpm_csr(__csr, __mask) 					  \
 	oldval = csr_read_allowed(__csr, &trap);			  \
@@ -707,9 +714,7 @@ int sbi_hart_reinit(struct sbi_scratch *scratch)
 	if (rc)
 		return rc;
 
-	sbi_smrnmi_hart_init(scratch);
-
-	return 0;
+	return sbi_smrnmi_hart_init(scratch);
 }
 
 int sbi_hart_init(struct sbi_scratch *scratch, bool cold_boot)

-- 
2.43.7