path: root/arch/mips/mm/r5432.c

/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * r5432.c: NEC Vr5432 processor.  We cannot use r4xx0.c because of
 *      its unique way-selection method for indexed operations.
 *
 * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
 * Copyright (C) 1997, 1998, 1999, 2000 Ralf Baechle (ralf@gnu.org)
 * Copyright (C) 2000 Jun Sun (jsun@mvista.com)
 *
 */

/*
 * [jsun]
 * In a sense, this is really silly.  We cannot re-use r4xx0.c because
 * the lowest-level indexed cache operation does not take way-selection
 * into account.  So all what I am doing here is to copy all the funcs
 * and macros (in r4kcache.h) relavent to R5432 to this file, and then
 * modify a few indexed cache operations.  *sigh*
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>

#include <asm/bcache.h>
#include <asm/io.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/system.h>
#include <asm/bootinfo.h>
#include <asm/mmu_context.h>

/* CP0 hazard avoidance. */
#define BARRIER __asm__ __volatile__(".set noreorder\n\t" \
				     "nop; nop; nop; nop; nop; nop;\n\t" \
				     ".set reorder\n\t")

#include <asm/asm.h>
#include <asm/cacheops.h>

#undef DEBUG_CACHE

/* Primary cache parameters. */
static int icache_size, dcache_size; /* Size in bytes */
static int ic_lsize, dc_lsize;       /* LineSize in bytes */


/* -------------------------------------------------------------------- */
/* #include <asm/r4kcache.h> */

extern inline void flush_icache_line_indexed(unsigned long addr)
{
	__asm__ __volatile__(
		".set noreorder\n\t"
		".set mips3\n\t"
		"cache %1, (%0)\n\t"
		"cache %1, 1(%0)\n\t"
		".set mips0\n\t"
		".set reorder"
		:
		: "r" (addr),
		  "i" (Index_Invalidate_I));
}

extern inline void flush_dcache_line_indexed(unsigned long addr)
{
	__asm__ __volatile__(
		".set noreorder\n\t"
		".set mips3\n\t"
		"cache %1, (%0)\n\t"
		"cache %1, 1(%0)\n\t"
		".set mips0\n\t"
		".set reorder"
		:
		: "r" (addr),
		  "i" (Index_Writeback_Inv_D));
}

extern inline void flush_icache_line(unsigned long addr)
{
	__asm__ __volatile__(
		".set noreorder\n\t"
		".set mips3\n\t"
		"cache %1, (%0)\n\t"
		".set mips0\n\t"
		".set reorder"
		:
		: "r" (addr),
		  "i" (Hit_Invalidate_I));
}

extern inline void flush_dcache_line(unsigned long addr)
{
	__asm__ __volatile__(
		".set noreorder\n\t"
		".set mips3\n\t"
		"cache %1, (%0)\n\t"
		".set mips0\n\t"
		".set reorder"
		:
		: "r" (addr),
		  "i" (Hit_Writeback_Inv_D));
}

extern inline void invalidate_dcache_line(unsigned long addr)
{
	__asm__ __volatile__(
		".set noreorder\n\t"
		".set mips3\n\t"
		"cache %1, (%0)\n\t"
		".set mips0\n\t"
		".set reorder"
		:
		: "r" (addr),
		  "i" (Hit_Invalidate_D));
}


/*
 * The next two are for badland addresses like signal trampolines.
 */
extern inline void protected_flush_icache_line(unsigned long addr)
{
	__asm__ __volatile__(
		".set noreorder\n\t"
		".set mips3\n"
		"1:\tcache %1,(%0)\n"
		"2:\t.set mips0\n\t"
		".set reorder\n\t"
		".section\t__ex_table,\"a\"\n\t"
		STR(PTR)"\t1b,2b\n\t"
		".previous"
		:
		: "r" (addr),
		  "i" (Hit_Invalidate_I));
}

extern inline void protected_writeback_dcache_line(unsigned long addr)
{
	__asm__ __volatile__(
		".set noreorder\n\t"
		".set mips3\n"
		"1:\tcache %1,(%0)\n"
		"2:\t.set mips0\n\t"
		".set reorder\n\t"
		".section\t__ex_table,\"a\"\n\t"
		STR(PTR)"\t1b,2b\n\t"
		".previous"
		:
		: "r" (addr),
		  "i" (Hit_Writeback_D));
}


#define cache32_unroll32(base,op)				\
	__asm__ __volatile__("					\
		.set noreorder;					\
		.set mips3;					\
		cache %1, 0x000(%0); cache %1, 0x020(%0);	\
		cache %1, 0x040(%0); cache %1, 0x060(%0);	\
		cache %1, 0x080(%0); cache %1, 0x0a0(%0);	\
		cache %1, 0x0c0(%0); cache %1, 0x0e0(%0);	\
		cache %1, 0x100(%0); cache %1, 0x120(%0);	\
		cache %1, 0x140(%0); cache %1, 0x160(%0);	\
		cache %1, 0x180(%0); cache %1, 0x1a0(%0);	\
		cache %1, 0x1c0(%0); cache %1, 0x1e0(%0);	\
		cache %1, 0x200(%0); cache %1, 0x220(%0);	\
		cache %1, 0x240(%0); cache %1, 0x260(%0);	\
		cache %1, 0x280(%0); cache %1, 0x2a0(%0);	\
		cache %1, 0x2c0(%0); cache %1, 0x2e0(%0);	\
		cache %1, 0x300(%0); cache %1, 0x320(%0);	\
		cache %1, 0x340(%0); cache %1, 0x360(%0);	\
		cache %1, 0x380(%0); cache %1, 0x3a0(%0);	\
		cache %1, 0x3c0(%0); cache %1, 0x3e0(%0);	\
		.set mips0;					\
		.set reorder"					\
		:						\
		: "r" (base),					\
		  "i" (op));

extern inline void blast_dcache32(void)
{
	unsigned long start = KSEG0;
	unsigned long end = (start + dcache_size/2);

	while(start < end) {
		cache32_unroll32(start,Index_Writeback_Inv_D);
		cache32_unroll32(start+1,Index_Writeback_Inv_D);
		start += 0x400;
	}
}

extern inline void blast_dcache32_page(unsigned long page)
{
	unsigned long start = page;
	unsigned long end = (start + PAGE_SIZE);

	while(start < end) {
		cache32_unroll32(start,Hit_Writeback_Inv_D);
		start += 0x400;
	}
}

extern inline void blast_dcache32_page_indexed(unsigned long page)
{
	unsigned long start = page;
	unsigned long end = (start + PAGE_SIZE);

	while(start < end) {
		cache32_unroll32(start,Index_Writeback_Inv_D);
		cache32_unroll32(start+1,Index_Writeback_Inv_D);
		start += 0x400;
	}
}

extern inline void blast_icache32(void)
{
	unsigned long start = KSEG0;
	unsigned long end = (start + icache_size/2);

	while(start < end) {
		cache32_unroll32(start,Index_Invalidate_I);
		cache32_unroll32(start+1,Index_Invalidate_I);
		start += 0x400;
	}
}

extern inline void blast_icache32_page(unsigned long page)
{
	unsigned long start = page;
	unsigned long end = (start + PAGE_SIZE);

	while(start < end) {
		cache32_unroll32(start,Hit_Invalidate_I);
		start += 0x400;
	}
}

extern inline void blast_icache32_page_indexed(unsigned long page)
{
	unsigned long start = page;
	unsigned long end = (start + PAGE_SIZE);

	while(start < end) {
		cache32_unroll32(start,Index_Invalidate_I);
		cache32_unroll32(start+1,Index_Invalidate_I);
		start += 0x400;
	}
}

/* -------------------------------------------------------------------- */

static void r5432_clear_page_d32(void * page)
{
	__asm__ __volatile__(
		".set\tnoreorder\n\t"
		".set\tnoat\n\t"
		".set\tmips3\n\t"
		"daddiu\t$1,%0,%2\n"
		"1:\tcache\t%3,(%0)\n\t"
		"sd\t$0,(%0)\n\t"
		"sd\t$0,8(%0)\n\t"
		"sd\t$0,16(%0)\n\t"
		"sd\t$0,24(%0)\n\t"
		"daddiu\t%0,64\n\t"
		"cache\t%3,-32(%0)\n\t"
		"sd\t$0,-32(%0)\n\t"
		"sd\t$0,-24(%0)\n\t"
		"sd\t$0,-16(%0)\n\t"
		"bne\t$1,%0,1b\n\t"
		"sd\t$0,-8(%0)\n\t"
		".set\tmips0\n\t"
		".set\tat\n\t"
		".set\treorder"
		:"=r" (page)
		:"0" (page),
		 "I" (PAGE_SIZE),
		 "i" (Create_Dirty_Excl_D)
		:"$1","memory");
}



/*
 * This is still inefficient.  We only can do better if we know the
 * virtual address where the copy will be accessed.
 */

static void r5432_copy_page_d32(void * to, void * from)
{
	unsigned long dummy1, dummy2;
	unsigned long reg1, reg2, reg3, reg4;

	__asm__ __volatile__(
		".set\tnoreorder\n\t"
		".set\tnoat\n\t"
		".set\tmips3\n\t"
		"daddiu\t$1,%0,%8\n"
		"1:\tcache\t%9,(%0)\n\t"
		"lw\t%2,(%1)\n\t"
		"lw\t%3,4(%1)\n\t"
		"lw\t%4,8(%1)\n\t"
		"lw\t%5,12(%1)\n\t"
		"sw\t%2,(%0)\n\t"
		"sw\t%3,4(%0)\n\t"
		"sw\t%4,8(%0)\n\t"
		"sw\t%5,12(%0)\n\t"
		"lw\t%2,16(%1)\n\t"
		"lw\t%3,20(%1)\n\t"
		"lw\t%4,24(%1)\n\t"
		"lw\t%5,28(%1)\n\t"
		"sw\t%2,16(%0)\n\t"
		"sw\t%3,20(%0)\n\t"
		"sw\t%4,24(%0)\n\t"
		"sw\t%5,28(%0)\n\t"
		"cache\t%9,32(%0)\n\t"
		"daddiu\t%0,64\n\t"
		"daddiu\t%1,64\n\t"
		"lw\t%2,-32(%1)\n\t"
		"lw\t%3,-28(%1)\n\t"
		"lw\t%4,-24(%1)\n\t"
		"lw\t%5,-20(%1)\n\t"
		"sw\t%2,-32(%0)\n\t"
		"sw\t%3,-28(%0)\n\t"
		"sw\t%4,-24(%0)\n\t"
		"sw\t%5,-20(%0)\n\t"
		"lw\t%2,-16(%1)\n\t"
		"lw\t%3,-12(%1)\n\t"
		"lw\t%4,-8(%1)\n\t"
		"lw\t%5,-4(%1)\n\t"
		"sw\t%2,-16(%0)\n\t"
		"sw\t%3,-12(%0)\n\t"
		"sw\t%4,-8(%0)\n\t"
		"bne\t$1,%0,1b\n\t"
		"sw\t%5,-4(%0)\n\t"
		".set\tmips0\n\t"
		".set\tat\n\t"
		".set\treorder"
		:"=r" (dummy1), "=r" (dummy2),
		 "=&r" (reg1), "=&r" (reg2), "=&r" (reg3), "=&r" (reg4)
		:"0" (to), "1" (from),
		 "I" (PAGE_SIZE),
		 "i" (Create_Dirty_Excl_D));
}


/*
 * If you think for one second that this stuff coming up is a lot
 * of bulky code eating too many kernel cache lines.  Think _again_.
 *
 * Consider:
 * 1) Taken branches have a 3 cycle penalty on R4k
 * 2) The branch itself is a real dead cycle on even R4600/R5000.
 * 3) Only one of the following variants of each type is even used by
 *    the kernel based upon the cache parameters we detect at boot time.
 *
 * QED.
 */

static inline void r5432_flush_cache_all_d32i32(void)
{
	blast_dcache32(); blast_icache32();
}

static void r5432_flush_cache_range_d32i32(struct mm_struct *mm,
					 unsigned long start,
					 unsigned long end)
{
	if (mm->context != 0) {
#ifdef DEBUG_CACHE
		printk("crange[%d,%08lx,%08lx]", (int)mm->context, start, end);
#endif
		blast_dcache32(); blast_icache32();
	}
}

/*
 * On architectures like the Sparc, we could get rid of lines in
 * the cache created only by a certain context, but on the MIPS
 * (and actually certain Sparc's) we cannot.
 */
static void r5432_flush_cache_mm_d32i32(struct mm_struct *mm)
{
	if (mm->context != 0) {
#ifdef DEBUG_CACHE
		printk("cmm[%d]", (int)mm->context);
#endif
		r5432_flush_cache_all_d32i32();
	}
}

static void r5432_flush_cache_page_d32i32(struct vm_area_struct *vma,
					unsigned long page)
{
	struct mm_struct *mm = vma->vm_mm;
	pgd_t *pgdp;
	pmd_t *pmdp;
	pte_t *ptep;

	/*
	 * If ownes no valid ASID yet, cannot possibly have gotten
	 * this page into the cache.
	 */
	if (mm->context == 0)
		return;

#ifdef DEBUG_CACHE
	printk("cpage[%d,%08lx]", (int)mm->context, page);
#endif
	page &= PAGE_MASK;
	pgdp = pgd_offset(mm, page);
	pmdp = pmd_offset(pgdp, page);
	ptep = pte_offset(pmdp, page);

	/*
	 * If the page isn't marked valid, the page cannot possibly be
	 * in the cache.
	 */
	if (!(pte_val(*ptep) & _PAGE_PRESENT))
		return;

	/*
	 * Doing flushes for another ASID than the current one is
	 * too difficult since stupid R4k caches do a TLB translation
	 * for every cache flush operation.  So we do indexed flushes
	 * in that case, which doesn't overly flush the cache too much.
	 */
	if ((mm == current->active_mm) && (pte_val(*ptep) & _PAGE_VALID)) {
		blast_dcache32_page(page);
	} else {
		/*
		 * Do indexed flush, too much work to get the (possible)
		 * tlb refills to work correctly.
		 */
		page = (KSEG0 + (page & (dcache_size - 1)));
		blast_dcache32_page_indexed(page);
	}
}


/* If the addresses passed to these routines are valid, they are
 * either:
 *
 * 1) In KSEG0, so we can do a direct flush of the page.
 * 2) In KSEG2, and since every process can translate those
 *    addresses all the time in kernel mode we can do a direct
 *    flush.
 * 3) In KSEG1, no flush necessary.
 */
static void r5432_flush_page_to_ram_d32(struct page *page)
{
	blast_dcache32_page((unsigned long)page_address(page));
}

static void 
r5432_flush_icache_range(unsigned long start, unsigned long end)
{
	r5432_flush_cache_all_d32i32();
}

/*
 * Ok, this seriously sucks.  We use them to flush a user page but don't
 * know the virtual address, so we have to blast away the whole icache
 * which is significantly more expensive than the real thing.
 */
static void
r5432_flush_icache_page_i32(struct vm_area_struct *vma, struct page *page)
{
	if (!(vma->vm_flags & VM_EXEC))
		return;

	r5432_flush_cache_all_d32i32();
}

/*
 * Writeback and invalidate the primary cache dcache before DMA.
 */
static void
r5432_dma_cache_wback_inv_pc(unsigned long addr, unsigned long size)
{
	unsigned long end, a;

	if (size >= dcache_size) {
		flush_cache_all();
	} else {
		a = addr & ~(dc_lsize - 1);
		end = (addr + size) & ~(dc_lsize - 1);
		while (1) {
			flush_dcache_line(a); /* Hit_Writeback_Inv_D */
			if (a == end) break;
			a += dc_lsize;
		}
	}
	bc_wback_inv(addr, size);
}

static void
r5432_dma_cache_inv_pc(unsigned long addr, unsigned long size)
{
	unsigned long end, a;

	if (size >= dcache_size) {
		flush_cache_all();
	} else {
		a = addr & ~(dc_lsize - 1);
		end = (addr + size) & ~(dc_lsize - 1);
		while (1) {
			flush_dcache_line(a); /* Hit_Writeback_Inv_D */
			if (a == end) break;
			a += dc_lsize;
		}
	}

	bc_inv(addr, size);
}

static void
r5432_dma_cache_wback(unsigned long addr, unsigned long size)
{
	panic("r5432_dma_cache called - should not happen.\n");
}

/*
 * While we're protected against bad userland addresses we don't care
 * very much about what happens in that case.  Usually a segmentation
 * fault will dump the process later on anyway ...
 */
static void r5432_flush_cache_sigtramp(unsigned long addr)
{
	unsigned long daddr, iaddr;

	daddr = addr & ~(dc_lsize - 1);
	protected_writeback_dcache_line(daddr);
	protected_writeback_dcache_line(daddr + dc_lsize);
	iaddr = addr & ~(ic_lsize - 1);
	protected_flush_icache_line(iaddr);
	protected_flush_icache_line(iaddr + ic_lsize);
}

#undef DEBUG_TLB
#undef DEBUG_TLBUPDATE

#define NTLB_ENTRIES       48  /* Fixed on all R4XX0 variants... */

#define NTLB_ENTRIES_HALF  24  /* Fixed on all R4XX0 variants... */

void flush_tlb_all(void)
{
	unsigned long old_ctx;
	int entry;
	unsigned long flags;

#ifdef DEBUG_TLB
	printk("[tlball]");
#endif

	__save_and_cli(flags);
	/* Save old context and create impossible VPN2 value */
	old_ctx = (get_entryhi() & 0xff);
	set_entryhi(KSEG0);
	set_entrylo0(0);
	set_entrylo1(0);
	BARRIER;

	entry = get_wired();

	/* Blast 'em all away. */
	while(entry < NTLB_ENTRIES) {
		set_index(entry);
		BARRIER;
		tlb_write_indexed();
		BARRIER;
		entry++;
	}
	BARRIER;
	set_entryhi(old_ctx);
	__restore_flags(flags);
}

void flush_tlb_mm(struct mm_struct *mm)
{
	if (mm->context != 0) {
		unsigned long flags;

#ifdef DEBUG_TLB
		printk("[tlbmm<%d>]", mm->context);
#endif
		__save_and_cli(flags);
		get_new_mmu_context(mm, asid_cache);
		if (mm == current->active_mm)
			set_entryhi(mm->context & 0xff);
		__restore_flags(flags);
	}
}

void flush_tlb_range(struct mm_struct *mm, unsigned long start,
				unsigned long end)
{
	if(mm->context != 0) {
		unsigned long flags;
		int size;

#ifdef DEBUG_TLB
		printk("[tlbrange<%02x,%08lx,%08lx>]", (mm->context & 0xff),
		       start, end);
#endif
		__save_and_cli(flags);
		size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
		size = (size + 1) >> 1;
		if(size <= NTLB_ENTRIES_HALF) {
			int oldpid = (get_entryhi() & 0xff);
			int newpid = (mm->context & 0xff);

			start &= (PAGE_MASK << 1);
			end += ((PAGE_SIZE << 1) - 1);
			end &= (PAGE_MASK << 1);
			while(start < end) {
				int idx;

				set_entryhi(start | newpid);
				start += (PAGE_SIZE << 1);
				BARRIER;
				tlb_probe();
				BARRIER;
				idx = get_index();
				set_entrylo0(0);
				set_entrylo1(0);
				set_entryhi(KSEG0);
				BARRIER;
				if(idx < 0)
					continue;
				tlb_write_indexed();
				BARRIER;
			}
			set_entryhi(oldpid);
		} else {
			get_new_mmu_context(mm, asid_cache);
			if (mm == current->active_mm)
				set_entryhi(mm->context & 0xff);
		}
		__restore_flags(flags);
	}
}

void flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
{
	if (vma->vm_mm->context != 0) {
		unsigned long flags;
		int oldpid, newpid, idx;

#ifdef DEBUG_TLB
		printk("[tlbpage<%d,%08lx>]", vma->vm_mm->context, page);
#endif
		newpid = (vma->vm_mm->context & 0xff);
		page &= (PAGE_MASK << 1);
		__save_and_cli(flags);
		oldpid = (get_entryhi() & 0xff);
		set_entryhi(page | newpid);
		BARRIER;
		tlb_probe();
		BARRIER;
		idx = get_index();
		set_entrylo0(0);
		set_entrylo1(0);
		set_entryhi(KSEG0);
		if(idx < 0)
			goto finish;
		BARRIER;
		tlb_write_indexed();

	finish:
		BARRIER;
		set_entryhi(oldpid);
		__restore_flags(flags);
	}
}

void pgd_init(unsigned long page)
{
	unsigned long *p = (unsigned long *) page;
	int i;

	for(i = 0; i < USER_PTRS_PER_PGD; i+=8) {
		p[i + 0] = (unsigned long) invalid_pte_table;
		p[i + 1] = (unsigned long) invalid_pte_table;
		p[i + 2] = (unsigned long) invalid_pte_table;
		p[i + 3] = (unsigned long) invalid_pte_table;
		p[i + 4] = (unsigned long) invalid_pte_table;
		p[i + 5] = (unsigned long) invalid_pte_table;
		p[i + 6] = (unsigned long) invalid_pte_table;
		p[i + 7] = (unsigned long) invalid_pte_table;
	}
}

/* We will need multiple versions of update_mmu_cache(), one that just
 * updates the TLB with the new pte(s), and another which also checks
 * for the R4k "end of page" hardware bug and does the needy.
 */
void update_mmu_cache(struct vm_area_struct * vma,
				 unsigned long address, pte_t pte)
{
	unsigned long flags;
	pgd_t *pgdp;
	pmd_t *pmdp;
	pte_t *ptep;
	int idx, pid;

	/*
	 * Handle debugger faulting in for debugee.
	 */
	if (current->active_mm != vma->vm_mm)
		return;

	pid = get_entryhi() & 0xff;

#ifdef DEBUG_TLB
	if((pid != (vma->vm_mm->context & 0xff)) || (vma->vm_mm->context == 0)) {
		printk("update_mmu_cache: Wheee, bogus tlbpid mmpid=%d tlbpid=%d\n",
		       (int) (vma->vm_mm->context & 0xff), pid);
	}
#endif

	__save_and_cli(flags);
	address &= (PAGE_MASK << 1);
	set_entryhi(address | (pid));
	pgdp = pgd_offset(vma->vm_mm, address);
	BARRIER;
	tlb_probe();
	BARRIER;
	pmdp = pmd_offset(pgdp, address);
	idx = get_index();
	ptep = pte_offset(pmdp, address);
	BARRIER;
	set_entrylo0(pte_val(*ptep++) >> 6);
	set_entrylo1(pte_val(*ptep) >> 6);
	set_entryhi(address | (pid));
	BARRIER;
	if(idx < 0) {
		tlb_write_random();
	} else {
		tlb_write_indexed();
	}
	BARRIER;
	set_entryhi(pid);
	BARRIER;
	__restore_flags(flags);
}

void show_regs(struct pt_regs * regs)
{
	/* Saved main processor registers. */
	printk("$0 : %08lx %08lx %08lx %08lx\n",
	       0UL, regs->regs[1], regs->regs[2], regs->regs[3]);
	printk("$4 : %08lx %08lx %08lx %08lx\n",
               regs->regs[4], regs->regs[5], regs->regs[6], regs->regs[7]);
	printk("$8 : %08lx %08lx %08lx %08lx\n",
	       regs->regs[8], regs->regs[9], regs->regs[10], regs->regs[11]);
	printk("$12: %08lx %08lx %08lx %08lx\n",
               regs->regs[12], regs->regs[13], regs->regs[14], regs->regs[15]);
	printk("$16: %08lx %08lx %08lx %08lx\n",
	       regs->regs[16], regs->regs[17], regs->regs[18], regs->regs[19]);
	printk("$20: %08lx %08lx %08lx %08lx\n",
               regs->regs[20], regs->regs[21], regs->regs[22], regs->regs[23]);
	printk("$24: %08lx %08lx\n",
	       regs->regs[24], regs->regs[25]);
	printk("$28: %08lx %08lx %08lx %08lx\n",
	       regs->regs[28], regs->regs[29], regs->regs[30], regs->regs[31]);

	/* Saved cp0 registers. */
	printk("epc   : %08lx\nStatus: %08lx\nCause : %08lx\n",
	       regs->cp0_epc, regs->cp0_status, regs->cp0_cause);
}
			
void add_wired_entry(unsigned long entrylo0, unsigned long entrylo1,
		     unsigned long entryhi, unsigned long pagemask)
{
        unsigned long flags;
        unsigned long wired;
        unsigned long old_pagemask;
        unsigned long old_ctx;

        __save_and_cli(flags);
        /* Save old context and create impossible VPN2 value */
        old_ctx = (get_entryhi() & 0xff);
        old_pagemask = get_pagemask();
        wired = get_wired();
        set_wired (wired + 1);
        set_index (wired);
        BARRIER;    
        set_pagemask (pagemask);
        set_entryhi(entryhi);
        set_entrylo0(entrylo0);
        set_entrylo1(entrylo1);
        BARRIER;    
        tlb_write_indexed();
        BARRIER;    
    
        set_entryhi(old_ctx);
        BARRIER;    
        set_pagemask (old_pagemask);
        flush_tlb_all();    
        __restore_flags(flags);
}

/* Detect and size the various r4k caches. */
static void __init probe_icache(unsigned long config)
{
	icache_size = 1 << (12 + ((config >> 9) & 7));
	ic_lsize = 16 << ((config >> 5) & 1);

	printk("Primary instruction cache %dkb, linesize %d bytes.\n",
	       icache_size >> 10, ic_lsize);
}

static void __init probe_dcache(unsigned long config)
{
	dcache_size = 1 << (12 + ((config >> 6) & 7));
	dc_lsize = 16 << ((config >> 4) & 1);

	printk("Primary data cache %dkb, linesize %d bytes.\n",
	       dcache_size >> 10, dc_lsize);
}


void __init ld_mmu_r5432(void)
{
	unsigned long config = read_32bit_cp0_register(CP0_CONFIG);

	printk("CPU revision is: %08x\n", read_32bit_cp0_register(CP0_PRID));

	change_cp0_config(CONF_CM_CMASK, CONF_CM_CACHABLE_NONCOHERENT);

	probe_icache(config);
	probe_dcache(config);

	_clear_page = r5432_clear_page_d32;
	_copy_page = r5432_copy_page_d32;
	_flush_cache_all = r5432_flush_cache_all_d32i32;
	___flush_cache_all = r5432_flush_cache_all_d32i32;
	_flush_page_to_ram = r5432_flush_page_to_ram_d32;
	_flush_cache_mm = r5432_flush_cache_mm_d32i32;
	_flush_cache_range = r5432_flush_cache_range_d32i32;
	_flush_cache_page = r5432_flush_cache_page_d32i32;
	_flush_icache_page = r5432_flush_icache_page_i32;
	_dma_cache_wback_inv = r5432_dma_cache_wback_inv_pc;
	_dma_cache_wback = r5432_dma_cache_wback;
	_dma_cache_inv = r5432_dma_cache_inv_pc;

	_flush_cache_sigtramp = r5432_flush_cache_sigtramp;
	_flush_icache_range = r5432_flush_icache_range;	/* Ouch */

	__flush_cache_all();
	write_32bit_cp0_register(CP0_WIRED, 0);

	/*
	 * You should never change this register:
	 *   - On R4600 1.7 the tlbp never hits for pages smaller than
	 *     the value in the c0_pagemask register.
	 *   - The entire mm handling assumes the c0_pagemask register to
	 *     be set for 4kb pages.
	 */
	write_32bit_cp0_register(CP0_PAGEMASK, PM_4K);
	flush_tlb_all();
}