MIPS: Octeon: Initialize and fixup device tree.

If a compiled in device tree template is used, trim out unwanted parts
based on legacy platform probing.

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: linux-kernel@vger.kernel.org
Cc: David Daney <david.daney@cavium.com>
Patchwork: https://patchwork.linux-mips.org/patch/3935/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 45 insertions, 0 deletions

diff --git a/arch/mips/cavium-octeon/setup.c b/arch/mips/cavium-octeon/setup.c
index 260dc247c05..919b0fb7bb1 100644
--- a/arch/mips/cavium-octeon/setup.c
+++ b/arch/mips/cavium-octeon/setup.c
@@ -21,6 +21,8 @@
 #include <linux/platform_device.h>
 #include <linux/serial_core.h>
 #include <linux/serial_8250.h>
+#include <linux/of_fdt.h>
+#include <linux/libfdt.h>
 
 #include <asm/processor.h>
 #include <asm/reboot.h>
@@ -775,3 +777,46 @@ void prom_free_prom_memory(void)
         }
 #endif
 }
+
+int octeon_prune_device_tree(void);
+
+extern const char __dtb_octeon_3xxx_begin;
+extern const char __dtb_octeon_3xxx_end;
+extern const char __dtb_octeon_68xx_begin;
+extern const char __dtb_octeon_68xx_end;
+void __init device_tree_init(void)
+{
+        int dt_size;
+        struct boot_param_header *fdt;
+        bool do_prune;
+
+        if (octeon_bootinfo->minor_version >= 3 && octeon_bootinfo->fdt_addr) {
+                fdt = phys_to_virt(octeon_bootinfo->fdt_addr);
+                if (fdt_check_header(fdt))
+                        panic("Corrupt Device Tree passed to kernel.");
+                dt_size = be32_to_cpu(fdt->totalsize);
+                do_prune = false;
+        } else if (OCTEON_IS_MODEL(OCTEON_CN68XX)) {
+                fdt = (struct boot_param_header *)&__dtb_octeon_68xx_begin;
+                dt_size = &__dtb_octeon_68xx_end - &__dtb_octeon_68xx_begin;
+                do_prune = true;
+        } else {
+                fdt = (struct boot_param_header *)&__dtb_octeon_3xxx_begin;
+                dt_size = &__dtb_octeon_3xxx_end - &__dtb_octeon_3xxx_begin;
+                do_prune = true;
+        }
+
+        /* Copy the default tree from init memory. */
+        initial_boot_params = early_init_dt_alloc_memory_arch(dt_size, 8);
+        if (initial_boot_params == NULL)
+                panic("Could not allocate initial_boot_params\n");
+        memcpy(initial_boot_params, fdt, dt_size);
+
+        if (do_prune) {
+                octeon_prune_device_tree();
+                pr_info("Using internal Device Tree.\n");
+        } else {
+                pr_info("Using passed Device Tree.\n");
+        }
+        unflatten_device_tree();
+}