xref: /openbmc/linux/arch/mips/kernel/prom.c (revision f2ffa5ab)

/*
 * MIPS support for CONFIG_OF device tree support
 *
 * Copyright (C) 2010 Cisco Systems Inc. <dediao@cisco.com>
 *
 * 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.
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/bootmem.h>
#include <linux/initrd.h>
#include <linux/debugfs.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>

#include <asm/page.h>
#include <asm/prom.h>

int __init early_init_dt_scan_memory_arch(unsigned long node,
					  const char *uname, int depth,
					  void *data)
{
	return early_init_dt_scan_memory(node, uname, depth, data);
}

void __init early_init_dt_add_memory_arch(u64 base, u64 size)
{
	return add_memory_region(base, size, BOOT_MEM_RAM);
}

int __init reserve_mem_mach(unsigned long addr, unsigned long size)
{
	return reserve_bootmem(addr, size, BOOTMEM_DEFAULT);
}

void __init free_mem_mach(unsigned long addr, unsigned long size)
{
	return free_bootmem(addr, size);
}

u64 __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
{
	return virt_to_phys(
		__alloc_bootmem(size, align, __pa(MAX_DMA_ADDRESS))
		);
}

#ifdef CONFIG_BLK_DEV_INITRD
void __init early_init_dt_setup_initrd_arch(unsigned long start,
					    unsigned long end)
{
	initrd_start = (unsigned long)__va(start);
	initrd_end = (unsigned long)__va(end);
	initrd_below_start_ok = 1;
}
#endif

/*
 * irq_create_of_mapping - Hook to resolve OF irq specifier into a Linux irq#
 *
 * Currently the mapping mechanism is trivial; simple flat hwirq numbers are
 * mapped 1:1 onto Linux irq numbers.  Cascaded irq controllers are not
 * supported.
 */
unsigned int irq_create_of_mapping(struct device_node *controller,
				   const u32 *intspec, unsigned int intsize)
{
	return intspec[0];
}
EXPORT_SYMBOL_GPL(irq_create_of_mapping);

void __init early_init_devtree(void *params)
{
	/* Setup flat device-tree pointer */
	initial_boot_params = params;

	/* Retrieve various informations from the /chosen node of the
	 * device-tree, including the platform type, initrd location and
	 * size, and more ...
	 */
	of_scan_flat_dt(early_init_dt_scan_chosen, NULL);

	/* Scan memory nodes */
	of_scan_flat_dt(early_init_dt_scan_root, NULL);
	of_scan_flat_dt(early_init_dt_scan_memory_arch, NULL);
}

void __init device_tree_init(void)
{
	unsigned long base, size;

	if (!initial_boot_params)
		return;

	base = virt_to_phys((void *)initial_boot_params);
	size = initial_boot_params->totalsize;

	/* Before we do anything, lets reserve the dt blob */
	reserve_mem_mach(base, size);

	unflatten_device_tree();

	/* free the space reserved for the dt blob */
	free_mem_mach(base, size);
}