linux/arch/mips/kernel/prom.c
Santosh Shilimkar 374d5c9964 of: Specify initrd location using 64-bit
On some PAE architectures, the entire range of physical memory could reside
outside the 32-bit limit.  These systems need the ability to specify the
initrd location using 64-bit numbers.

This patch globally modifies the early_init_dt_setup_initrd_arch() function to
use 64-bit numbers instead of the current unsigned long.

There has been quite a bit of debate about whether to use u64 or phys_addr_t.
It was concluded to stick to u64 to be consistent with rest of the device
tree code. As summarized by Geert, "The address to load the initrd is decided
by the bootloader/user and set at that point later in time. The dtb should not
be tied to the kernel you are booting"

More details on the discussion can be found here:
https://lkml.org/lkml/2013/6/20/690
https://lkml.org/lkml/2012/9/13/544

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
2013-07-24 11:10:01 +01:00

114 lines
2.6 KiB
C

/*
* 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/export.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>
static char mips_machine_name[64] = "Unknown";
__init void mips_set_machine_name(const char *name)
{
if (name == NULL)
return;
strlcpy(mips_machine_name, name, sizeof(mips_machine_name));
pr_info("MIPS: machine is %s\n", mips_get_machine_name());
}
char *mips_get_machine_name(void)
{
return mips_machine_name;
}
#ifdef CONFIG_OF
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);
}
void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
{
return __alloc_bootmem(size, align, __pa(MAX_DMA_ADDRESS));
}
#ifdef CONFIG_BLK_DEV_INITRD
void __init early_init_dt_setup_initrd_arch(u64 start, u64 end)
{
initrd_start = (unsigned long)__va(start);
initrd_end = (unsigned long)__va(end);
initrd_below_start_ok = 1;
}
#endif
int __init early_init_dt_scan_model(unsigned long node, const char *uname,
int depth, void *data)
{
if (!depth) {
char *model = of_get_flat_dt_prop(node, "model", NULL);
if (model)
mips_set_machine_name(model);
}
return 0;
}
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, arcs_cmdline);
/* Scan memory nodes */
of_scan_flat_dt(early_init_dt_scan_root, NULL);
of_scan_flat_dt(early_init_dt_scan_memory_arch, NULL);
/* try to load the mips machine name */
of_scan_flat_dt(early_init_dt_scan_model, NULL);
}
void __init __dt_setup_arch(struct boot_param_header *bph)
{
if (be32_to_cpu(bph->magic) != OF_DT_HEADER) {
pr_err("DTB has bad magic, ignoring builtin OF DTB\n");
return;
}
initial_boot_params = bph;
early_init_devtree(initial_boot_params);
}
#endif