3 files changed, 69 insertions, 22 deletions

diff --git a/arch/mips/generic/board-sead3.c b/arch/mips/generic/board-sead3.c
index 97186a3a5d21..39e11bd249cf 100644
--- a/arch/mips/generic/board-sead3.c
+++ b/arch/mips/generic/board-sead3.c
@@ -138,6 +138,14 @@ static __init int remove_gic(void *fdt)
         return 0;
 }
 
+static const struct mips_fdt_fixup sead3_fdt_fixups[] __initconst = {
+        { yamon_dt_append_cmdline, "append command line" },
+        { append_memory, "append memory" },
+        { remove_gic, "remove GIC when not present" },
+        { yamon_dt_serial_config, "append serial configuration" },
+        { },
+};
+
 static __init const void *sead3_fixup_fdt(const void *fdt,
                                           const void *match_data)
 {
@@ -152,29 +160,10 @@ static __init const void *sead3_fixup_fdt(const void *fdt,
 
         fw_init_cmdline();
 
-        err = fdt_open_into(fdt, fdt_buf, sizeof(fdt_buf));
-        if (err)
-                panic("Unable to open FDT: %d", err);
-
-        err = yamon_dt_append_cmdline(fdt_buf);
-        if (err)
-                panic("Unable to patch FDT: %d", err);
-
-        err = append_memory(fdt_buf);
-        if (err)
-                panic("Unable to patch FDT: %d", err);
-
-        err = remove_gic(fdt_buf);
-        if (err)
-                panic("Unable to patch FDT: %d", err);
-
-        err = yamon_dt_serial_config(fdt_buf);
-        if (err)
-                panic("Unable to patch FDT: %d", err);
-
-        err = fdt_pack(fdt_buf);
+        err = apply_mips_fdt_fixups(fdt_buf, sizeof(fdt_buf),
+                                    fdt, sead3_fdt_fixups);
         if (err)
-                panic("Unable to pack FDT: %d\n", err);
+                panic("Unable to fixup FDT: %d", err);
 
         return fdt_buf;
 }
diff --git a/arch/mips/generic/init.c b/arch/mips/generic/init.c
index 4af619215410..4a9a1edbfb29 100644
--- a/arch/mips/generic/init.c
+++ b/arch/mips/generic/init.c
@@ -122,6 +122,33 @@ void __init device_tree_init(void)
                 err = register_up_smp_ops();
 }
 
+int __init apply_mips_fdt_fixups(void *fdt_out, size_t fdt_out_size,
+                                 const void *fdt_in,
+                                 const struct mips_fdt_fixup *fixups)
+{
+        int err;
+
+        err = fdt_open_into(fdt_in, fdt_out, fdt_out_size);
+        if (err) {
+                pr_err("Failed to open FDT\n");
+                return err;
+        }
+
+        for (; fixups->apply; fixups++) {
+                err = fixups->apply(fdt_out);
+                if (err) {
+                        pr_err("Failed to apply FDT fixup \"%s\"\n",
+                               fixups->description);
+                        return err;
+                }
+        }
+
+        err = fdt_pack(fdt_out);
+        if (err)
+                pr_err("Failed to pack FDT\n");
+        return err;
+}
+
 void __init plat_time_init(void)
 {
         struct device_node *np;
diff --git a/arch/mips/include/asm/machine.h b/arch/mips/include/asm/machine.h
index 6b444cd9526f..ecb6c7335484 100644
--- a/arch/mips/include/asm/machine.h
+++ b/arch/mips/include/asm/machine.h
@@ -60,4 +60,35 @@ mips_machine_is_compatible(const struct mips_machine *mach, const void *fdt)
         return NULL;
 }
 
+/**
+ * struct mips_fdt_fixup - Describe a fixup to apply to an FDT
+ * @apply: applies the fixup to @fdt, returns zero on success else -errno
+ * @description: a short description of the fixup
+ *
+ * Describes a fixup applied to an FDT blob by the @apply function. The
+ * @description field provides a short description of the fixup intended for
+ * use in error messages if the @apply function returns non-zero.
+ */
+struct mips_fdt_fixup {
+        int (*apply)(void *fdt);
+        const char *description;
+};
+
+/**
+ * apply_mips_fdt_fixups() - apply fixups to an FDT blob
+ * @fdt_out: buffer in which to place the fixed-up FDT
+ * @fdt_out_size: the size of the @fdt_out buffer
+ * @fdt_in: the FDT blob
+ * @fixups: pointer to an array of fixups to be applied
+ *
+ * Loop through the array of fixups pointed to by @fixups, calling the apply
+ * function on each until either one returns an error or we reach the end of
+ * the list as indicated by an entry with a NULL apply field.
+ *
+ * Return: zero on success, else -errno
+ */
+extern int __init apply_mips_fdt_fixups(void *fdt_out, size_t fdt_out_size,
+                                        const void *fdt_in,
+                                        const struct mips_fdt_fixup *fixups);
+
 #endif /* __MIPS_ASM_MACHINE_H__ */