lib: utils: fdt_fixup: Allow preserving PMU properties

Add a Kconfig option to control PMU fixup, so the next
stage software can dump the PMU node including event
mapping information for debugging purposes.

Signed-off-by: Yu Chien Peter Lin <peterlin@andestech.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

lib/utils/fdt/Kconfig

@@ -15,4 +15,11 @@ config FDT_PMU
 	bool "FDT performance monitoring unit (PMU) support"
 	default n
 
+config FDT_FIXUPS_PRESERVE_PMU_NODE
+	bool "Preserve PMU node in device-tree"
+	depends on FDT_PMU
+	default n
+	help
+	  Preserve PMU node properties for debugging purposes.
+
 endif

lib/utils/fdt/fdt_fixup.c

@@ -394,5 +394,8 @@ void fdt_fixups(void *fdt)
 	fdt_plic_fixup(fdt);
 
 	fdt_reserved_memory_fixup(fdt);
+
+#ifndef CONFIG_FDT_FIXUPS_PRESERVE_PMU_NODE
 	fdt_pmu_fixup(fdt);
+#endif
 }