/*
 * arch/alpha/boot/bootpz.c
 *
 * Copyright (C) 1997 Jay Estabrook
 *
 * This file is used for creating a compressed BOOTP file for the
 * Linux/AXP kernel
 *
 * based significantly on the arch/alpha/boot/main.c of Linus Torvalds
 * and the decompression code from MILO.
 */
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <generated/utsrelease.h>
#include <linux/mm.h>

#include <asm/console.h>
#include <asm/hwrpb.h>
#include <asm/pgtable.h>
#include <asm/io.h>

#include <stdarg.h>

#include "kzsize.h"

/* FIXME FIXME FIXME */
#define MALLOC_AREA_SIZE 0x200000 /* 2MB for now */
/* FIXME FIXME FIXME */


/*
  WARNING NOTE

  It is very possible that turning on additional messages may cause
  kernel image corruption due to stack usage to do the printing.

*/

#undef DEBUG_CHECK_RANGE
#undef DEBUG_ADDRESSES
#undef DEBUG_LAST_STEPS

extern unsigned long switch_to_osf_pal(unsigned long nr,
	struct pcb_struct * pcb_va, struct pcb_struct * pcb_pa,
	unsigned long *vptb);

extern int decompress_kernel(void* destination, void *source,
			     size_t ksize, size_t kzsize);

extern void move_stack(unsigned long new_stack);

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.
 */
#define VPTB	((unsigned long *) 0x200000000)

static inline unsigned long
find_pa(unsigned long address)
{
	unsigned long result;

	result = VPTB[address >> 13];
	result >>= 32;
	result <<= 13;
	result |= address & 0x1fff;
	return result;
}	

int
check_range(unsigned long vstart, unsigned long vend,
	    unsigned long kstart, unsigned long kend)
{
	unsigned long vaddr, kaddr;

#ifdef DEBUG_CHECK_RANGE
	srm_printk("check_range: V[0x%lx:0x%lx] K[0x%lx:0x%lx]\n",
		   vstart, vend, kstart, kend);
#endif
	/* do some range checking for detecting an overlap... */
	for (vaddr = vstart; vaddr <= vend; vaddr += PAGE_SIZE)
	{
		kaddr = (find_pa(vaddr) | PAGE_OFFSET);
		if (kaddr >= kstart && kaddr <= kend)
		{
#ifdef DEBUG_CHECK_RANGE
			srm_printk("OVERLAP: vaddr 0x%lx kaddr 0x%lx"
				   " [0x%lx:0x%lx]\n",
				   vaddr, kaddr, kstart, kend);
#endif
			return 1;
		}
	}
	return 0;
}

/*
 * 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 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 = (struct pcb_struct *)find_pa((unsigned long)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 */
}