MIPS: platform: Allow for DTB to be moved during kernel relocation

Add plat_fdt_relocated(void*) API to allow the kernel relocation code to
update platform's information about the DTB location if the DTB had to
be moved due to being placed in a location used by the relocated kernel.

Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14611/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

diff --git a/arch/mips/generic/init.c b/arch/mips/generic/init.c
index d493ccbf274af0dccfcc0639d4446a0460eca284..4af619215410a09946ef82c7c2cb37755423ba59 100644 (file)
--- a/arch/mips/generic/init.c
+++ b/arch/mips/generic/init.c
@@ -88,6 +88,19 @@ void __init *plat_get_fdt(void)
        return (void *)fdt;
 }
 
+void __init plat_fdt_relocated(void *new_location)
+{
+       /*
+        * reset fdt as the cached value would point to the location
+        * before relocations happened and update the location argument
+        * if it was passed using UHI
+        */
+       fdt = NULL;
+
+       if (fw_arg0 == -2)
+               fw_arg1 = (unsigned long)new_location;
+}
+
 void __init plat_mem_setup(void)
 {
        if (mach && mach->fixup_fdt)

diff --git a/arch/mips/include/asm/bootinfo.h b/arch/mips/include/asm/bootinfo.h
index ee9f5f2d18fc00e0f51705c745174c7d95bbccf4..e26a093bb17a2e34e2079f1e5cda21a66052e843 100644 (file)
--- a/arch/mips/include/asm/bootinfo.h
+++ b/arch/mips/include/asm/bootinfo.h
@@ -164,6 +164,19 @@ static inline void plat_swiotlb_setup(void) {}
  * Return: Pointer to the flattened device tree blob.
  */
 extern void *plat_get_fdt(void);
+
+#ifdef CONFIG_RELOCATABLE
+
+/**
+ * plat_fdt_relocated() - Update platform's information about relocated dtb
+ *
+ * This function provides a platform-independent API to set platform's
+ * information about relocated DTB if it needs to be moved due to kernel
+ * relocation occurring at boot.
+ */
+void plat_fdt_relocated(void *new_location);
+
+#endif /* CONFIG_RELOCATABLE */
 #endif /* CONFIG_USE_OF */
 
 #endif /* _ASM_BOOTINFO_H */