MIPS: ralink: adds OF code

Until there is a generic MIPS way of handing the DTB over from bootloader to
kernel we rely on a built in devicetrees. The OF code also remaps those register
ranges that we use global in our drivers.

Signed-off-by: John Crispin <blogic@openwrt.org>
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/4895/
This commit is contained in:
John Crispin 2013-01-20 22:02:01 +01:00
parent 3f0a06b036
commit 3a5bfe7bdb

107
arch/mips/ralink/of.c Normal file
View file

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/*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*
* Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
* Copyright (C) 2008-2009 Gabor Juhos <juhosg@openwrt.org>
* Copyright (C) 2013 John Crispin <blogic@openwrt.org>
*/
#include <linux/io.h>
#include <linux/clk.h>
#include <linux/init.h>
#include <linux/of_fdt.h>
#include <linux/kernel.h>
#include <linux/bootmem.h>
#include <linux/of_platform.h>
#include <linux/of_address.h>
#include <asm/reboot.h>
#include <asm/bootinfo.h>
#include <asm/addrspace.h>
#include "common.h"
__iomem void *rt_sysc_membase;
__iomem void *rt_memc_membase;
extern struct boot_param_header __dtb_start;
__iomem void *plat_of_remap_node(const char *node)
{
struct resource res;
struct device_node *np;
np = of_find_compatible_node(NULL, NULL, node);
if (!np)
panic("Failed to find %s node", node);
if (of_address_to_resource(np, 0, &res))
panic("Failed to get resource for %s", node);
if ((request_mem_region(res.start,
resource_size(&res),
res.name) < 0))
panic("Failed to request resources for %s", node);
return ioremap_nocache(res.start, resource_size(&res));
}
void __init device_tree_init(void)
{
unsigned long base, size;
void *fdt_copy;
if (!initial_boot_params)
return;
base = virt_to_phys((void *)initial_boot_params);
size = be32_to_cpu(initial_boot_params->totalsize);
/* Before we do anything, lets reserve the dt blob */
reserve_bootmem(base, size, BOOTMEM_DEFAULT);
/* The strings in the flattened tree are referenced directly by the
* device tree, so copy the flattened device tree from init memory
* to regular memory.
*/
fdt_copy = alloc_bootmem(size);
memcpy(fdt_copy, initial_boot_params, size);
initial_boot_params = fdt_copy;
unflatten_device_tree();
/* free the space reserved for the dt blob */
free_bootmem(base, size);
}
void __init plat_mem_setup(void)
{
set_io_port_base(KSEG1);
/*
* Load the builtin devicetree. This causes the chosen node to be
* parsed resulting in our memory appearing
*/
__dt_setup_arch(&__dtb_start);
}
static int __init plat_of_setup(void)
{
static struct of_device_id of_ids[3];
int len = sizeof(of_ids[0].compatible);
if (!of_have_populated_dt())
panic("device tree not present");
strncpy(of_ids[0].compatible, soc_info.compatible, len);
strncpy(of_ids[1].compatible, "palmbus", len);
if (of_platform_populate(NULL, of_ids, NULL, NULL))
panic("failed to populate DT\n");
return 0;
}
arch_initcall(plat_of_setup);