tlb_nohash_low.S

/*
 * This file contains low-level functions for performing various
 * types of TLB invalidations on various processors with no hash
 * table.
 *
 * This file implements the following functions for all no-hash
 * processors. Some aren't implemented for some variants. Some
 * are inline in tlbflush.h
 *
 *	- tlbil_va
 *	- tlbil_pid
 *	- tlbil_all
 *	- tlbivax_bcast (not yet)
 *
 * Code mostly moved over from misc_32.S
 *
 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
 *
 * Partially rewritten by Cort Dougan (cort@cs.nmt.edu)
 * Paul Mackerras, Kumar Gala and Benjamin Herrenschmidt.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 *
 */

#include <asm/reg.h>
#include <asm/page.h>
#include <asm/cputable.h>
#include <asm/mmu.h>
#include <asm/ppc_asm.h>
#include <asm/asm-offsets.h>
#include <asm/processor.h>

#if defined(CONFIG_40x)

/*
 * 40x implementation needs only tlbil_va
 */
_GLOBAL(_tlbil_va)
	/* We run the search with interrupts disabled because we have to change
	 * the PID and I don't want to preempt when that happens.
	 */
	mfmsr	r5
	mfspr	r6,SPRN_PID
	wrteei	0
	mtspr	SPRN_PID,r4
	tlbsx.	r3, 0, r3
	mtspr	SPRN_PID,r6
	wrtee	r5
	bne	1f
	sync
	/* There are only 64 TLB entries, so r3 < 64, which means bit 25 is
	 * clear. Since 25 is the V bit in the TLB_TAG, loading this value
	 * will invalidate the TLB entry. */
	tlbwe	r3, r3, TLB_TAG
	isync
1:	blr

#elif defined(CONFIG_8xx)

/*
 * Nothing to do for 8xx, everything is inline
 */

#elif defined(CONFIG_44x)

/*
 * 440 implementation uses tlbsx/we for tlbil_va and a full sweep
 * of the TLB for everything else.
 */
_GLOBAL(_tlbil_va)
	mfspr	r5,SPRN_MMUCR
	rlwimi	r5,r4,0,24,31			/* Set TID */

	/* We have to run the search with interrupts disabled, otherwise
	 * an interrupt which causes a TLB miss can clobber the MMUCR
	 * between the mtspr and the tlbsx.
	 *
	 * Critical and Machine Check interrupts take care of saving
	 * and restoring MMUCR, so only normal interrupts have to be
	 * taken care of.
	 */
	mfmsr	r4
	wrteei	0
	mtspr	SPRN_MMUCR,r5
	tlbsx.	r3, 0, r3
	wrtee	r4
	bne	1f
	sync
	/* There are only 64 TLB entries, so r3 < 64,
	 * which means bit 22, is clear.  Since 22 is
	 * the V bit in the TLB_PAGEID, loading this
	 * value will invalidate the TLB entry.
	 */
	tlbwe	r3, r3, PPC44x_TLB_PAGEID
	isync
1:	blr

_GLOBAL(_tlbil_all)
_GLOBAL(_tlbil_pid)
	li	r3,0
	sync

	/* Load high watermark */
	lis	r4,tlb_44x_hwater@ha
	lwz	r5,tlb_44x_hwater@l(r4)

1:	tlbwe	r3,r3,PPC44x_TLB_PAGEID
	addi	r3,r3,1
	cmpw	0,r3,r5
	ble	1b

	isync
	blr

#elif defined(CONFIG_FSL_BOOKE)
/*
 * FSL BookE implementations. Currently _pid and _all are the
 * same. This will change when tlbilx is actually supported and
 * performs invalidate-by-PID. This change will be driven by
 * mmu_features conditional
 */

/*
 * Flush MMU TLB on the local processor
 */
_GLOBAL(_tlbil_pid)
_GLOBAL(_tlbil_all)
#define MMUCSR0_TLBFI	(MMUCSR0_TLB0FI | MMUCSR0_TLB1FI | \
			 MMUCSR0_TLB2FI | MMUCSR0_TLB3FI)
	li	r3,(MMUCSR0_TLBFI)@l
	mtspr	SPRN_MMUCSR0, r3
1:
	mfspr	r3,SPRN_MMUCSR0
	andi.	r3,r3,MMUCSR0_TLBFI@l
	bne	1b
	msync
	isync
	blr

/*
 * Flush MMU TLB for a particular address, but only on the local processor
 * (no broadcast)
 */
_GLOBAL(_tlbil_va)
	mfmsr	r10
	wrteei	0
	slwi	r4,r4,16
	mtspr	SPRN_MAS6,r4		/* assume AS=0 for now */
	tlbsx	0,r3
	mfspr	r4,SPRN_MAS1		/* check valid */
	andis.	r3,r4,MAS1_VALID@h
	beq	1f
	rlwinm	r4,r4,0,1,31
	mtspr	SPRN_MAS1,r4
	tlbwe
	msync
	isync
1:	wrtee	r10
	blr
#elif
#error Unsupported processor type !
#endif