MIPS: Add helper function to allow platforms to point at a DTB.
Add __dt_setup_arch() that can be called to load a builtin DT.
Additionally we add a macro to allow loading a specific symbol
from the __dtb_* section.
Signed-off-by: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3715/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/include/asm/prom.h b/arch/mips/include/asm/prom.h
index 40ed259..7206d44 100644
--- a/arch/mips/include/asm/prom.h
+++ b/arch/mips/include/asm/prom.h
@@ -36,6 +36,17 @@
}
#define pci_address_to_pio pci_address_to_pio
+struct boot_param_header;
+
+extern void __dt_setup_arch(struct boot_param_header *bph);
+
+#define dt_setup_arch(sym) \
+({ \
+ extern struct boot_param_header __dtb_##sym##_begin; \
+ \
+ __dt_setup_arch(&__dtb_##sym##_begin); \
+})
+
#else /* CONFIG_OF */
static inline void device_tree_init(void) { }
#endif /* CONFIG_OF */
diff --git a/arch/mips/kernel/prom.c b/arch/mips/kernel/prom.c
index 558b539..4c788d2 100644
--- a/arch/mips/kernel/prom.c
+++ b/arch/mips/kernel/prom.c
@@ -95,3 +95,14 @@
/* free the space reserved for the dt blob */
free_mem_mach(base, size);
}
+
+void __init __dt_setup_arch(struct boot_param_header *bph)
+{
+ if (be32_to_cpu(bph->magic) != OF_DT_HEADER) {
+ pr_err("DTB has bad magic, ignoring builtin OF DTB\n");
+
+ return;
+ }
+
+ initial_boot_params = bph;
+}