swh:1:snp:32555a3fd8878f019c2ebd6c964bc1edcaeff337
Tip revision: dc47ce90c3a822cd7c9e9339fe4d5f61dcb26b50 authored by Linus Torvalds on 09 December 2011, 23:09:32 UTC
Linux 3.2-rc5
Linux 3.2-rc5
Tip revision: dc47ce9
setup.c
/*
* Copyright (C) 2004-2006 Atmel Corporation
*
* 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/clk.h>
#include <linux/init.h>
#include <linux/initrd.h>
#include <linux/sched.h>
#include <linux/console.h>
#include <linux/ioport.h>
#include <linux/bootmem.h>
#include <linux/fs.h>
#include <linux/module.h>
#include <linux/pfn.h>
#include <linux/root_dev.h>
#include <linux/cpu.h>
#include <linux/kernel.h>
#include <asm/sections.h>
#include <asm/processor.h>
#include <asm/pgtable.h>
#include <asm/setup.h>
#include <asm/sysreg.h>
#include <mach/board.h>
#include <mach/init.h>
extern int root_mountflags;
/*
* Initialize loops_per_jiffy as 5000000 (500MIPS).
* Better make it too large than too small...
*/
struct avr32_cpuinfo boot_cpu_data = {
.loops_per_jiffy = 5000000
};
EXPORT_SYMBOL(boot_cpu_data);
static char __initdata command_line[COMMAND_LINE_SIZE];
/*
* Standard memory resources
*/
static struct resource __initdata kernel_data = {
.name = "Kernel data",
.start = 0,
.end = 0,
.flags = IORESOURCE_MEM,
};
static struct resource __initdata kernel_code = {
.name = "Kernel code",
.start = 0,
.end = 0,
.flags = IORESOURCE_MEM,
.sibling = &kernel_data,
};
/*
* Available system RAM and reserved regions as singly linked
* lists. These lists are traversed using the sibling pointer in
* struct resource and are kept sorted at all times.
*/
static struct resource *__initdata system_ram;
static struct resource *__initdata reserved = &kernel_code;
/*
* We need to allocate these before the bootmem allocator is up and
* running, so we need this "cache". 32 entries are probably enough
* for all but the most insanely complex systems.
*/
static struct resource __initdata res_cache[32];
static unsigned int __initdata res_cache_next_free;
static void __init resource_init(void)
{
struct resource *mem, *res;
struct resource *new;
kernel_code.start = __pa(init_mm.start_code);
for (mem = system_ram; mem; mem = mem->sibling) {
new = alloc_bootmem_low(sizeof(struct resource));
memcpy(new, mem, sizeof(struct resource));
new->sibling = NULL;
if (request_resource(&iomem_resource, new))
printk(KERN_WARNING "Bad RAM resource %08x-%08x\n",
mem->start, mem->end);
}
for (res = reserved; res; res = res->sibling) {
new = alloc_bootmem_low(sizeof(struct resource));
memcpy(new, res, sizeof(struct resource));
new->sibling = NULL;
if (insert_resource(&iomem_resource, new))
printk(KERN_WARNING
"Bad reserved resource %s (%08x-%08x)\n",
res->name, res->start, res->end);
}
}
static void __init
add_physical_memory(resource_size_t start, resource_size_t end)
{
struct resource *new, *next, **pprev;
for (pprev = &system_ram, next = system_ram; next;
pprev = &next->sibling, next = next->sibling) {
if (end < next->start)
break;
if (start <= next->end) {
printk(KERN_WARNING
"Warning: Physical memory map is broken\n");
printk(KERN_WARNING
"Warning: %08x-%08x overlaps %08x-%08x\n",
start, end, next->start, next->end);
return;
}
}
if (res_cache_next_free >= ARRAY_SIZE(res_cache)) {
printk(KERN_WARNING
"Warning: Failed to add physical memory %08x-%08x\n",
start, end);
return;
}
new = &res_cache[res_cache_next_free++];
new->start = start;
new->end = end;
new->name = "System RAM";
new->flags = IORESOURCE_MEM;
*pprev = new;
}
static int __init
add_reserved_region(resource_size_t start, resource_size_t end,
const char *name)
{
struct resource *new, *next, **pprev;
if (end < start)
return -EINVAL;
if (res_cache_next_free >= ARRAY_SIZE(res_cache))
return -ENOMEM;
for (pprev = &reserved, next = reserved; next;
pprev = &next->sibling, next = next->sibling) {
if (end < next->start)
break;
if (start <= next->end)
return -EBUSY;
}
new = &res_cache[res_cache_next_free++];
new->start = start;
new->end = end;
new->name = name;
new->sibling = next;
new->flags = IORESOURCE_MEM;
*pprev = new;
return 0;
}
static unsigned long __init
find_free_region(const struct resource *mem, resource_size_t size,
resource_size_t align)
{
struct resource *res;
unsigned long target;
target = ALIGN(mem->start, align);
for (res = reserved; res; res = res->sibling) {
if ((target + size) <= res->start)
break;
if (target <= res->end)
target = ALIGN(res->end + 1, align);
}
if ((target + size) > (mem->end + 1))
return mem->end + 1;
return target;
}
static int __init
alloc_reserved_region(resource_size_t *start, resource_size_t size,
resource_size_t align, const char *name)
{
struct resource *mem;
resource_size_t target;
int ret;
for (mem = system_ram; mem; mem = mem->sibling) {
target = find_free_region(mem, size, align);
if (target <= mem->end) {
ret = add_reserved_region(target, target + size - 1,
name);
if (!ret)
*start = target;
return ret;
}
}
return -ENOMEM;
}
/*
* Early framebuffer allocation. Works as follows:
* - If fbmem_size is zero, nothing will be allocated or reserved.
* - If fbmem_start is zero when setup_bootmem() is called,
* a block of fbmem_size bytes will be reserved before bootmem
* initialization. It will be aligned to the largest page size
* that fbmem_size is a multiple of.
* - If fbmem_start is nonzero, an area of size fbmem_size will be
* reserved at the physical address fbmem_start if possible. If
* it collides with other reserved memory, a different block of
* same size will be allocated, just as if fbmem_start was zero.
*
* Board-specific code may use these variables to set up platform data
* for the framebuffer driver if fbmem_size is nonzero.
*/
resource_size_t __initdata fbmem_start;
resource_size_t __initdata fbmem_size;
/*
* "fbmem=xxx[kKmM]" allocates the specified amount of boot memory for
* use as framebuffer.
*
* "fbmem=xxx[kKmM]@yyy[kKmM]" defines a memory region of size xxx and
* starting at yyy to be reserved for use as framebuffer.
*
* The kernel won't verify that the memory region starting at yyy
* actually contains usable RAM.
*/
static int __init early_parse_fbmem(char *p)
{
int ret;
unsigned long align;
fbmem_size = memparse(p, &p);
if (*p == '@') {
fbmem_start = memparse(p + 1, &p);
ret = add_reserved_region(fbmem_start,
fbmem_start + fbmem_size - 1,
"Framebuffer");
if (ret) {
printk(KERN_WARNING
"Failed to reserve framebuffer memory\n");
fbmem_start = 0;
}
}
if (!fbmem_start) {
if ((fbmem_size & 0x000fffffUL) == 0)
align = 0x100000; /* 1 MiB */
else if ((fbmem_size & 0x0000ffffUL) == 0)
align = 0x10000; /* 64 KiB */
else
align = 0x1000; /* 4 KiB */
ret = alloc_reserved_region(&fbmem_start, fbmem_size,
align, "Framebuffer");
if (ret) {
printk(KERN_WARNING
"Failed to allocate framebuffer memory\n");
fbmem_size = 0;
} else {
memset(__va(fbmem_start), 0, fbmem_size);
}
}
return 0;
}
early_param("fbmem", early_parse_fbmem);
/*
* Pick out the memory size. We look for mem=size@start,
* where start and size are "size[KkMmGg]"
*/
static int __init early_mem(char *p)
{
resource_size_t size, start;
start = system_ram->start;
size = memparse(p, &p);
if (*p == '@')
start = memparse(p + 1, &p);
system_ram->start = start;
system_ram->end = system_ram->start + size - 1;
return 0;
}
early_param("mem", early_mem);
static int __init parse_tag_core(struct tag *tag)
{
if (tag->hdr.size > 2) {
if ((tag->u.core.flags & 1) == 0)
root_mountflags &= ~MS_RDONLY;
ROOT_DEV = new_decode_dev(tag->u.core.rootdev);
}
return 0;
}
__tagtable(ATAG_CORE, parse_tag_core);
static int __init parse_tag_mem(struct tag *tag)
{
unsigned long start, end;
/*
* Ignore zero-sized entries. If we're running standalone, the
* SDRAM code may emit such entries if something goes
* wrong...
*/
if (tag->u.mem_range.size == 0)
return 0;
start = tag->u.mem_range.addr;
end = tag->u.mem_range.addr + tag->u.mem_range.size - 1;
add_physical_memory(start, end);
return 0;
}
__tagtable(ATAG_MEM, parse_tag_mem);
static int __init parse_tag_rdimg(struct tag *tag)
{
#ifdef CONFIG_BLK_DEV_INITRD
struct tag_mem_range *mem = &tag->u.mem_range;
int ret;
if (initrd_start) {
printk(KERN_WARNING
"Warning: Only the first initrd image will be used\n");
return 0;
}
ret = add_reserved_region(mem->addr, mem->addr + mem->size - 1,
"initrd");
if (ret) {
printk(KERN_WARNING
"Warning: Failed to reserve initrd memory\n");
return ret;
}
initrd_start = (unsigned long)__va(mem->addr);
initrd_end = initrd_start + mem->size;
#else
printk(KERN_WARNING "RAM disk image present, but "
"no initrd support in kernel, ignoring\n");
#endif
return 0;
}
__tagtable(ATAG_RDIMG, parse_tag_rdimg);
static int __init parse_tag_rsvd_mem(struct tag *tag)
{
struct tag_mem_range *mem = &tag->u.mem_range;
return add_reserved_region(mem->addr, mem->addr + mem->size - 1,
"Reserved");
}
__tagtable(ATAG_RSVD_MEM, parse_tag_rsvd_mem);
static int __init parse_tag_cmdline(struct tag *tag)
{
strlcpy(boot_command_line, tag->u.cmdline.cmdline, COMMAND_LINE_SIZE);
return 0;
}
__tagtable(ATAG_CMDLINE, parse_tag_cmdline);
static int __init parse_tag_clock(struct tag *tag)
{
/*
* We'll figure out the clocks by peeking at the system
* manager regs directly.
*/
return 0;
}
__tagtable(ATAG_CLOCK, parse_tag_clock);
/*
* The board_number correspond to the bd->bi_board_number in U-Boot. This
* parameter is only available during initialisation and can be used in some
* kind of board identification.
*/
u32 __initdata board_number;
static int __init parse_tag_boardinfo(struct tag *tag)
{
board_number = tag->u.boardinfo.board_number;
return 0;
}
__tagtable(ATAG_BOARDINFO, parse_tag_boardinfo);
/*
* Scan the tag table for this tag, and call its parse function. The
* tag table is built by the linker from all the __tagtable
* declarations.
*/
static int __init parse_tag(struct tag *tag)
{
extern struct tagtable __tagtable_begin, __tagtable_end;
struct tagtable *t;
for (t = &__tagtable_begin; t < &__tagtable_end; t++)
if (tag->hdr.tag == t->tag) {
t->parse(tag);
break;
}
return t < &__tagtable_end;
}
/*
* Parse all tags in the list we got from the boot loader
*/
static void __init parse_tags(struct tag *t)
{
for (; t->hdr.tag != ATAG_NONE; t = tag_next(t))
if (!parse_tag(t))
printk(KERN_WARNING
"Ignoring unrecognised tag 0x%08x\n",
t->hdr.tag);
}
/*
* Find a free memory region large enough for storing the
* bootmem bitmap.
*/
static unsigned long __init
find_bootmap_pfn(const struct resource *mem)
{
unsigned long bootmap_pages, bootmap_len;
unsigned long node_pages = PFN_UP(resource_size(mem));
unsigned long bootmap_start;
bootmap_pages = bootmem_bootmap_pages(node_pages);
bootmap_len = bootmap_pages << PAGE_SHIFT;
/*
* Find a large enough region without reserved pages for
* storing the bootmem bitmap. We can take advantage of the
* fact that all lists have been sorted.
*
* We have to check that we don't collide with any reserved
* regions, which includes the kernel image and any RAMDISK
* images.
*/
bootmap_start = find_free_region(mem, bootmap_len, PAGE_SIZE);
return bootmap_start >> PAGE_SHIFT;
}
#define MAX_LOWMEM HIGHMEM_START
#define MAX_LOWMEM_PFN PFN_DOWN(MAX_LOWMEM)
static void __init setup_bootmem(void)
{
unsigned bootmap_size;
unsigned long first_pfn, bootmap_pfn, pages;
unsigned long max_pfn, max_low_pfn;
unsigned node = 0;
struct resource *res;
printk(KERN_INFO "Physical memory:\n");
for (res = system_ram; res; res = res->sibling)
printk(" %08x-%08x\n", res->start, res->end);
printk(KERN_INFO "Reserved memory:\n");
for (res = reserved; res; res = res->sibling)
printk(" %08x-%08x: %s\n",
res->start, res->end, res->name);
nodes_clear(node_online_map);
if (system_ram->sibling)
printk(KERN_WARNING "Only using first memory bank\n");
for (res = system_ram; res; res = NULL) {
first_pfn = PFN_UP(res->start);
max_low_pfn = max_pfn = PFN_DOWN(res->end + 1);
bootmap_pfn = find_bootmap_pfn(res);
if (bootmap_pfn > max_pfn)
panic("No space for bootmem bitmap!\n");
if (max_low_pfn > MAX_LOWMEM_PFN) {
max_low_pfn = MAX_LOWMEM_PFN;
#ifndef CONFIG_HIGHMEM
/*
* Lowmem is memory that can be addressed
* directly through P1/P2
*/
printk(KERN_WARNING
"Node %u: Only %ld MiB of memory will be used.\n",
node, MAX_LOWMEM >> 20);
printk(KERN_WARNING "Use a HIGHMEM enabled kernel.\n");
#else
#error HIGHMEM is not supported by AVR32 yet
#endif
}
/* Initialize the boot-time allocator with low memory only. */
bootmap_size = init_bootmem_node(NODE_DATA(node), bootmap_pfn,
first_pfn, max_low_pfn);
/*
* Register fully available RAM pages with the bootmem
* allocator.
*/
pages = max_low_pfn - first_pfn;
free_bootmem_node (NODE_DATA(node), PFN_PHYS(first_pfn),
PFN_PHYS(pages));
/* Reserve space for the bootmem bitmap... */
reserve_bootmem_node(NODE_DATA(node),
PFN_PHYS(bootmap_pfn),
bootmap_size,
BOOTMEM_DEFAULT);
/* ...and any other reserved regions. */
for (res = reserved; res; res = res->sibling) {
if (res->start > PFN_PHYS(max_pfn))
break;
/*
* resource_init will complain about partial
* overlaps, so we'll just ignore such
* resources for now.
*/
if (res->start >= PFN_PHYS(first_pfn)
&& res->end < PFN_PHYS(max_pfn))
reserve_bootmem_node(NODE_DATA(node),
res->start,
resource_size(res),
BOOTMEM_DEFAULT);
}
node_set_online(node);
}
}
void __init setup_arch (char **cmdline_p)
{
struct clk *cpu_clk;
init_mm.start_code = (unsigned long)_text;
init_mm.end_code = (unsigned long)_etext;
init_mm.end_data = (unsigned long)_edata;
init_mm.brk = (unsigned long)_end;
/*
* Include .init section to make allocations easier. It will
* be removed before the resource is actually requested.
*/
kernel_code.start = __pa(__init_begin);
kernel_code.end = __pa(init_mm.end_code - 1);
kernel_data.start = __pa(init_mm.end_code);
kernel_data.end = __pa(init_mm.brk - 1);
parse_tags(bootloader_tags);
setup_processor();
setup_platform();
setup_board();
cpu_clk = clk_get(NULL, "cpu");
if (IS_ERR(cpu_clk)) {
printk(KERN_WARNING "Warning: Unable to get CPU clock\n");
} else {
unsigned long cpu_hz = clk_get_rate(cpu_clk);
/*
* Well, duh, but it's probably a good idea to
* increment the use count.
*/
clk_enable(cpu_clk);
boot_cpu_data.clk = cpu_clk;
boot_cpu_data.loops_per_jiffy = cpu_hz * 4;
printk("CPU: Running at %lu.%03lu MHz\n",
((cpu_hz + 500) / 1000) / 1000,
((cpu_hz + 500) / 1000) % 1000);
}
strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
*cmdline_p = command_line;
parse_early_param();
setup_bootmem();
#ifdef CONFIG_VT
conswitchp = &dummy_con;
#endif
paging_init();
resource_init();
}