[PATCH] arm: spl: Use separate fault handlers instead of a single common one

[Csókás Bence]

It may be necessary to set breakpoints etc. on a specific fault handler in SPL.
Add a Kconfig option to separate the different handlers into their own individual infinite loops.

Signed-off-by: Csókás Bence <csokas.bence at prolan.hu>
---
 arch/arm/Kconfig       | 10 ++++++++++
 arch/arm/lib/vectors.S | 18 ++++++++++++++++++
 2 files changed, 28 insertions(+)

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 328e2ddc33..47494cb72b 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -79,6 +79,16 @@ config SPL_SYS_NO_VECTOR_TABLE
 	depends on SPL
 	bool
 
+config SPL_USE_SEPARATE_FAULT_HANDLERS
+	bool "Use separate fault handlers instead of a single common one"
+	depends on !SPL_SYS_NO_VECTOR_TABLE
+	default n
+	help
+	  Instead of a common fault handler, generate a separate one for
+	  undefined_instruction, software_interrupt, prefetch_abort etc.
+	  This is for debugging purposes, when you want to set breakpoints
+	  on them separately.
+
 config LINUX_KERNEL_IMAGE_HEADER
 	depends on ARM64
 	bool
diff --git a/arch/arm/lib/vectors.S b/arch/arm/lib/vectors.S
index 7cf7d1636f..a14bca6fb8 100644
--- a/arch/arm/lib/vectors.S
+++ b/arch/arm/lib/vectors.S
@@ -138,11 +138,29 @@ _fiq:			.word fiq
 #if !CONFIG_IS_ENABLED(SYS_NO_VECTOR_TABLE)
 	.align	5
 undefined_instruction:
+#if CONFIG_IS_ENABLED(USE_SEPARATE_FAULT_HANDLERS)
+	b	undefined_instruction
+#endif
 software_interrupt:
+#if CONFIG_IS_ENABLED(USE_SEPARATE_FAULT_HANDLERS)
+	b	software_interrupt
+#endif
 prefetch_abort:
+#if CONFIG_IS_ENABLED(USE_SEPARATE_FAULT_HANDLERS)
+	b	prefetch_abort
+#endif
 data_abort:
+#if CONFIG_IS_ENABLED(USE_SEPARATE_FAULT_HANDLERS)
+	b	data_abort
+#endif
 not_used:
+#if CONFIG_IS_ENABLED(USE_SEPARATE_FAULT_HANDLERS)
+	b	not_used
+#endif
 irq:
+#if CONFIG_IS_ENABLED(USE_SEPARATE_FAULT_HANDLERS)
+	b	irq
+#endif
 fiq:
 1:
 	b	1b			/* hang and never return */
-- 
2.25.1