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/*
* arch/alpha/boot/main.c
*
* Copyright (C) 1994, 1995 Linus Torvalds
*
* This file is the bootloader for the Linux/AXP kernel
*/
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/version.h>
#include <linux/mm.h>
#include <asm/system.h>
#include <asm/console.h>
#include <asm/hwrpb.h>
#include <asm/pgtable.h>
#include <stdarg.h>
#include "ksize.h"
extern int vsprintf(char *, const char *, va_list);
extern unsigned long switch_to_osf_pal(unsigned long nr,
struct pcb_struct * pcb_va, struct pcb_struct * pcb_pa,
unsigned long *vptb);
struct hwrpb_struct *hwrpb = INIT_HWRPB;
static struct pcb_struct pcb_va[1];
/*
* Find a physical address of a virtual object..
*
* This is easy using the virtual page table address.
*/
static inline void *
find_pa(unsigned long *vptb, void *ptr)
{
unsigned long address = (unsigned long) ptr;
unsigned long result;
result = vptb[address >> 13];
result >>= 32;
result <<= 13;
result |= address & 0x1fff;
return (void *) result;
}
/*
* This function moves into OSF/1 pal-code, and has a temporary
* PCB for that. The kernel proper should replace this PCB with
* the real one as soon as possible.
*
* The page table muckery in here depends on the fact that the boot
* code has the L1 page table identity-map itself in the second PTE
* in the L1 page table. Thus the L1-page is virtually addressable
* itself (through three levels) at virtual address 0x200802000.
*/
#define VPTB ((unsigned long *) 0x200000000)
#define L1 ((unsigned long *) 0x200802000)
void
pal_init(void)
{
unsigned long i, rev;
struct percpu_struct * percpu;
struct pcb_struct * pcb_pa;
/* Create the dummy PCB. */
pcb_va->ksp = 0;
pcb_va->usp = 0;
pcb_va->ptbr = L1[1] >> 32;
pcb_va->asn = 0;
pcb_va->pcc = 0;
pcb_va->unique = 0;
pcb_va->flags = 1;
pcb_va->res1 = 0;
pcb_va->res2 = 0;
pcb_pa = find_pa(VPTB, pcb_va);
/*
* a0 = 2 (OSF)
* a1 = return address, but we give the asm the vaddr of the PCB
* a2 = physical addr of PCB
* a3 = new virtual page table pointer
* a4 = KSP (but the asm sets it)
*/
srm_printk("Switching to OSF PAL-code .. ");
i = switch_to_osf_pal(2, pcb_va, pcb_pa, VPTB);
if (i) {
srm_printk("failed, code %ld\n", i);
__halt();
}
percpu = (struct percpu_struct *)
(INIT_HWRPB->processor_offset + (unsigned long) INIT_HWRPB);
rev = percpu->pal_revision = percpu->palcode_avail[2];
srm_printk("Ok (rev %lx)\n", rev);
tbia(); /* do it directly in case we are SMP */
}
static inline long openboot(void)
{
char bootdev[256];
long result;
result = callback_getenv(ENV_BOOTED_DEV, bootdev, 255);
if (result < 0)
return result;
return callback_open(bootdev, result & 255);
}
static inline long close(long dev)
{
return callback_close(dev);
}
static inline long load(long dev, unsigned long addr, unsigned long count)
{
char bootfile[256];
extern char _end;
long result, boot_size = &_end - (char *) BOOT_ADDR;
result = callback_getenv(ENV_BOOTED_FILE, bootfile, 255);
if (result < 0)
return result;
result &= 255;
bootfile[result] = '\0';
if (result)
srm_printk("Boot file specification (%s) not implemented\n",
bootfile);
return callback_read(dev, count, addr, boot_size/512 + 1);
}
/*
* Start the kernel.
*/
static void runkernel(void)
{
__asm__ __volatile__(
"bis %1,%1,$30\n\t"
"bis %0,%0,$26\n\t"
"ret ($26)"
: /* no outputs: it doesn't even return */
: "r" (START_ADDR),
"r" (PAGE_SIZE + INIT_STACK));
}
void start_kernel(void)
{
long i;
long dev;
int nbytes;
char envval[256];
srm_printk("Linux/AXP bootloader for Linux " UTS_RELEASE "\n");
if (INIT_HWRPB->pagesize != 8192) {
srm_printk("Expected 8kB pages, got %ldkB\n", INIT_HWRPB->pagesize >> 10);
return;
}
pal_init();
dev = openboot();
if (dev < 0) {
srm_printk("Unable to open boot device: %016lx\n", dev);
return;
}
dev &= 0xffffffff;
srm_printk("Loading vmlinux ...");
i = load(dev, START_ADDR, KERNEL_SIZE);
close(dev);
if (i != KERNEL_SIZE) {
srm_printk("Failed (%lx)\n", i);
return;
}
nbytes = callback_getenv(ENV_BOOTED_OSFLAGS, envval, sizeof(envval));
if (nbytes < 0) {
nbytes = 0;
}
envval[nbytes] = '\0';
strcpy((char*)ZERO_PGE, envval);
srm_printk(" Ok\nNow booting the kernel\n");
runkernel();
for (i = 0 ; i < 0x100000000 ; i++)
/* nothing */;
__halt();
}
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