cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
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tlb_low.S (9862B)


      1/* SPDX-License-Identifier: GPL-2.0-or-later */
      2/*
      3 * This file contains low-level functions for performing various
      4 * types of TLB invalidations on various processors with no hash
      5 * table.
      6 *
      7 * This file implements the following functions for all no-hash
      8 * processors. Some aren't implemented for some variants. Some
      9 * are inline in tlbflush.h
     10 *
     11 *	- tlbil_va
     12 *	- tlbil_pid
     13 *	- tlbil_all
     14 *	- tlbivax_bcast
     15 *
     16 * Code mostly moved over from misc_32.S
     17 *
     18 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
     19 *
     20 * Partially rewritten by Cort Dougan (cort@cs.nmt.edu)
     21 * Paul Mackerras, Kumar Gala and Benjamin Herrenschmidt.
     22 */
     23
     24#include <asm/reg.h>
     25#include <asm/page.h>
     26#include <asm/cputable.h>
     27#include <asm/mmu.h>
     28#include <asm/ppc_asm.h>
     29#include <asm/asm-offsets.h>
     30#include <asm/processor.h>
     31#include <asm/bug.h>
     32#include <asm/asm-compat.h>
     33#include <asm/feature-fixups.h>
     34
     35#if defined(CONFIG_40x)
     36
     37/*
     38 * 40x implementation needs only tlbil_va
     39 */
     40_GLOBAL(__tlbil_va)
     41	/* We run the search with interrupts disabled because we have to change
     42	 * the PID and I don't want to preempt when that happens.
     43	 */
     44	mfmsr	r5
     45	mfspr	r6,SPRN_PID
     46	wrteei	0
     47	mtspr	SPRN_PID,r4
     48	tlbsx.	r3, 0, r3
     49	mtspr	SPRN_PID,r6
     50	wrtee	r5
     51	bne	1f
     52	sync
     53	/* There are only 64 TLB entries, so r3 < 64, which means bit 25 is
     54	 * clear. Since 25 is the V bit in the TLB_TAG, loading this value
     55	 * will invalidate the TLB entry. */
     56	tlbwe	r3, r3, TLB_TAG
     57	isync
     581:	blr
     59
     60#elif defined(CONFIG_PPC_8xx)
     61
     62/*
     63 * Nothing to do for 8xx, everything is inline
     64 */
     65
     66#elif defined(CONFIG_44x) /* Includes 47x */
     67
     68/*
     69 * 440 implementation uses tlbsx/we for tlbil_va and a full sweep
     70 * of the TLB for everything else.
     71 */
     72_GLOBAL(__tlbil_va)
     73	mfspr	r5,SPRN_MMUCR
     74	mfmsr   r10
     75
     76	/*
     77	 * We write 16 bits of STID since 47x supports that much, we
     78	 * will never be passed out of bounds values on 440 (hopefully)
     79	 */
     80	rlwimi  r5,r4,0,16,31
     81
     82	/* We have to run the search with interrupts disabled, otherwise
     83	 * an interrupt which causes a TLB miss can clobber the MMUCR
     84	 * between the mtspr and the tlbsx.
     85	 *
     86	 * Critical and Machine Check interrupts take care of saving
     87	 * and restoring MMUCR, so only normal interrupts have to be
     88	 * taken care of.
     89	 */
     90	wrteei	0
     91	mtspr	SPRN_MMUCR,r5
     92	tlbsx.	r6,0,r3
     93	bne	10f
     94	sync
     95#ifndef CONFIG_PPC_47x
     96	/* On 440 There are only 64 TLB entries, so r3 < 64, which means bit
     97	 * 22, is clear.  Since 22 is the V bit in the TLB_PAGEID, loading this
     98	 * value will invalidate the TLB entry.
     99	 */
    100	tlbwe	r6,r6,PPC44x_TLB_PAGEID
    101#else
    102	oris	r7,r6,0x8000	/* specify way explicitly */
    103	clrrwi	r4,r3,12	/* get an EPN for the hashing with V = 0 */
    104	ori	r4,r4,PPC47x_TLBE_SIZE
    105	tlbwe   r4,r7,0		/* write it */
    106#endif /* !CONFIG_PPC_47x */
    107	isync
    10810:	wrtee	r10
    109	blr
    110
    111_GLOBAL(_tlbil_all)
    112_GLOBAL(_tlbil_pid)
    113#ifndef CONFIG_PPC_47x
    114	li	r3,0
    115	sync
    116
    117	/* Load high watermark */
    118	lis	r4,tlb_44x_hwater@ha
    119	lwz	r5,tlb_44x_hwater@l(r4)
    120
    1211:	tlbwe	r3,r3,PPC44x_TLB_PAGEID
    122	addi	r3,r3,1
    123	cmpw	0,r3,r5
    124	ble	1b
    125
    126	isync
    127	blr
    128#else
    129	/* 476 variant. There's not simple way to do this, hopefully we'll
    130	 * try to limit the amount of such full invalidates
    131	 */
    132	mfmsr	r11		/* Interrupts off */
    133	wrteei	0
    134	li	r3,-1		/* Current set */
    135	lis	r10,tlb_47x_boltmap@h
    136	ori	r10,r10,tlb_47x_boltmap@l
    137	lis	r7,0x8000	/* Specify way explicitly */
    138
    139	b	9f		/* For each set */
    140
    1411:	li	r9,4		/* Number of ways */
    142	li	r4,0		/* Current way */
    143	li	r6,0		/* Default entry value 0 */
    144	andi.	r0,r8,1		/* Check if way 0 is bolted */
    145	mtctr	r9		/* Load way counter */
    146	bne-	3f		/* Bolted, skip loading it */
    147
    1482:	/* For each way */
    149	or	r5,r3,r4	/* Make way|index for tlbre */
    150	rlwimi	r5,r5,16,8,15	/* Copy index into position */
    151	tlbre	r6,r5,0		/* Read entry */
    1523:	addis	r4,r4,0x2000	/* Next way */
    153	andi.	r0,r6,PPC47x_TLB0_VALID /* Valid entry ? */
    154	beq	4f		/* Nope, skip it */
    155	rlwimi	r7,r5,0,1,2	/* Insert way number */
    156	rlwinm	r6,r6,0,21,19	/* Clear V */
    157	tlbwe   r6,r7,0		/* Write it */
    1584:	bdnz	2b		/* Loop for each way */
    159	srwi	r8,r8,1		/* Next boltmap bit */
    1609:	cmpwi	cr1,r3,255	/* Last set done ? */
    161	addi	r3,r3,1		/* Next set */
    162	beq	cr1,1f		/* End of loop */
    163	andi.	r0,r3,0x1f	/* Need to load a new boltmap word ? */
    164	bne	1b		/* No, loop */
    165	lwz	r8,0(r10)	/* Load boltmap entry */
    166	addi	r10,r10,4	/* Next word */
    167	b	1b		/* Then loop */
    1681:	isync			/* Sync shadows */
    169	wrtee	r11
    170	blr
    171#endif /* !CONFIG_PPC_47x */
    172
    173#ifdef CONFIG_PPC_47x
    174
    175/*
    176 * _tlbivax_bcast is only on 47x. We don't bother doing a runtime
    177 * check though, it will blow up soon enough if we mistakenly try
    178 * to use it on a 440.
    179 */
    180_GLOBAL(_tlbivax_bcast)
    181	mfspr	r5,SPRN_MMUCR
    182	mfmsr	r10
    183	rlwimi	r5,r4,0,16,31
    184	wrteei	0
    185	mtspr	SPRN_MMUCR,r5
    186	isync
    187	PPC_TLBIVAX(0, R3)
    188	isync
    189	eieio
    190	tlbsync
    191BEGIN_FTR_SECTION
    192	b	1f
    193END_FTR_SECTION_IFSET(CPU_FTR_476_DD2)
    194	sync
    195	wrtee	r10
    196	blr
    197/*
    198 * DD2 HW could hang if in instruction fetch happens before msync completes.
    199 * Touch enough instruction cache lines to ensure cache hits
    200 */
    2011:	mflr	r9
    202	bcl	20,31,$+4
    2032:	mflr	r6
    204	li	r7,32
    205	PPC_ICBT(0,R6,R7)		/* touch next cache line */
    206	add	r6,r6,r7
    207	PPC_ICBT(0,R6,R7)		/* touch next cache line */
    208	add	r6,r6,r7
    209	PPC_ICBT(0,R6,R7)		/* touch next cache line */
    210	sync
    211	nop
    212	nop
    213	nop
    214	nop
    215	nop
    216	nop
    217	nop
    218	nop
    219	mtlr	r9
    220	wrtee	r10
    221	blr
    222#endif /* CONFIG_PPC_47x */
    223
    224#elif defined(CONFIG_FSL_BOOKE)
    225/*
    226 * FSL BookE implementations.
    227 *
    228 * Since feature sections are using _SECTION_ELSE we need
    229 * to have the larger code path before the _SECTION_ELSE
    230 */
    231
    232/*
    233 * Flush MMU TLB on the local processor
    234 */
    235_GLOBAL(_tlbil_all)
    236BEGIN_MMU_FTR_SECTION
    237	li	r3,(MMUCSR0_TLBFI)@l
    238	mtspr	SPRN_MMUCSR0, r3
    2391:
    240	mfspr	r3,SPRN_MMUCSR0
    241	andi.	r3,r3,MMUCSR0_TLBFI@l
    242	bne	1b
    243MMU_FTR_SECTION_ELSE
    244	PPC_TLBILX_ALL(0,R0)
    245ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_USE_TLBILX)
    246	msync
    247	isync
    248	blr
    249
    250_GLOBAL(_tlbil_pid)
    251BEGIN_MMU_FTR_SECTION
    252	slwi	r3,r3,16
    253	mfmsr	r10
    254	wrteei	0
    255	mfspr	r4,SPRN_MAS6	/* save MAS6 */
    256	mtspr	SPRN_MAS6,r3
    257	PPC_TLBILX_PID(0,R0)
    258	mtspr	SPRN_MAS6,r4	/* restore MAS6 */
    259	wrtee	r10
    260MMU_FTR_SECTION_ELSE
    261	li	r3,(MMUCSR0_TLBFI)@l
    262	mtspr	SPRN_MMUCSR0, r3
    2631:
    264	mfspr	r3,SPRN_MMUCSR0
    265	andi.	r3,r3,MMUCSR0_TLBFI@l
    266	bne	1b
    267ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_USE_TLBILX)
    268	msync
    269	isync
    270	blr
    271
    272/*
    273 * Flush MMU TLB for a particular address, but only on the local processor
    274 * (no broadcast)
    275 */
    276_GLOBAL(__tlbil_va)
    277	mfmsr	r10
    278	wrteei	0
    279	slwi	r4,r4,16
    280	ori	r4,r4,(MAS6_ISIZE(BOOK3E_PAGESZ_4K))@l
    281	mtspr	SPRN_MAS6,r4		/* assume AS=0 for now */
    282BEGIN_MMU_FTR_SECTION
    283	tlbsx	0,r3
    284	mfspr	r4,SPRN_MAS1		/* check valid */
    285	andis.	r3,r4,MAS1_VALID@h
    286	beq	1f
    287	rlwinm	r4,r4,0,1,31
    288	mtspr	SPRN_MAS1,r4
    289	tlbwe
    290MMU_FTR_SECTION_ELSE
    291	PPC_TLBILX_VA(0,R3)
    292ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_USE_TLBILX)
    293	msync
    294	isync
    2951:	wrtee	r10
    296	blr
    297#elif defined(CONFIG_PPC_BOOK3E)
    298/*
    299 * New Book3E (>= 2.06) implementation
    300 *
    301 * Note: We may be able to get away without the interrupt masking stuff
    302 * if we save/restore MAS6 on exceptions that might modify it
    303 */
    304_GLOBAL(_tlbil_pid)
    305	slwi	r4,r3,MAS6_SPID_SHIFT
    306	mfmsr	r10
    307	wrteei	0
    308	mtspr	SPRN_MAS6,r4
    309	PPC_TLBILX_PID(0,R0)
    310	wrtee	r10
    311	msync
    312	isync
    313	blr
    314
    315_GLOBAL(_tlbil_pid_noind)
    316	slwi	r4,r3,MAS6_SPID_SHIFT
    317	mfmsr	r10
    318	ori	r4,r4,MAS6_SIND
    319	wrteei	0
    320	mtspr	SPRN_MAS6,r4
    321	PPC_TLBILX_PID(0,R0)
    322	wrtee	r10
    323	msync
    324	isync
    325	blr
    326
    327_GLOBAL(_tlbil_all)
    328	PPC_TLBILX_ALL(0,R0)
    329	msync
    330	isync
    331	blr
    332
    333_GLOBAL(_tlbil_va)
    334	mfmsr	r10
    335	wrteei	0
    336	cmpwi	cr0,r6,0
    337	slwi	r4,r4,MAS6_SPID_SHIFT
    338	rlwimi	r4,r5,MAS6_ISIZE_SHIFT,MAS6_ISIZE_MASK
    339	beq	1f
    340	rlwimi	r4,r6,MAS6_SIND_SHIFT,MAS6_SIND
    3411:	mtspr	SPRN_MAS6,r4		/* assume AS=0 for now */
    342	PPC_TLBILX_VA(0,R3)
    343	msync
    344	isync
    345	wrtee	r10
    346	blr
    347
    348_GLOBAL(_tlbivax_bcast)
    349	mfmsr	r10
    350	wrteei	0
    351	cmpwi	cr0,r6,0
    352	slwi	r4,r4,MAS6_SPID_SHIFT
    353	rlwimi	r4,r5,MAS6_ISIZE_SHIFT,MAS6_ISIZE_MASK
    354	beq	1f
    355	rlwimi	r4,r6,MAS6_SIND_SHIFT,MAS6_SIND
    3561:	mtspr	SPRN_MAS6,r4		/* assume AS=0 for now */
    357	PPC_TLBIVAX(0,R3)
    358	eieio
    359	tlbsync
    360	sync
    361	wrtee	r10
    362	blr
    363#else
    364#error Unsupported processor type !
    365#endif
    366
    367#if defined(CONFIG_PPC_FSL_BOOK3E)
    368/*
    369 * extern void loadcam_entry(unsigned int index)
    370 *
    371 * Load TLBCAM[index] entry in to the L2 CAM MMU
    372 * Must preserve r7, r8, r9, r10, r11, r12
    373 */
    374_GLOBAL(loadcam_entry)
    375	mflr	r5
    376	LOAD_REG_ADDR_PIC(r4, TLBCAM)
    377	mtlr	r5
    378	mulli	r5,r3,TLBCAM_SIZE
    379	add	r3,r5,r4
    380	lwz	r4,TLBCAM_MAS0(r3)
    381	mtspr	SPRN_MAS0,r4
    382	lwz	r4,TLBCAM_MAS1(r3)
    383	mtspr	SPRN_MAS1,r4
    384	PPC_LL	r4,TLBCAM_MAS2(r3)
    385	mtspr	SPRN_MAS2,r4
    386	lwz	r4,TLBCAM_MAS3(r3)
    387	mtspr	SPRN_MAS3,r4
    388BEGIN_MMU_FTR_SECTION
    389	lwz	r4,TLBCAM_MAS7(r3)
    390	mtspr	SPRN_MAS7,r4
    391END_MMU_FTR_SECTION_IFSET(MMU_FTR_BIG_PHYS)
    392	isync
    393	tlbwe
    394	isync
    395	blr
    396
    397/*
    398 * Load multiple TLB entries at once, using an alternate-space
    399 * trampoline so that we don't have to care about whether the same
    400 * TLB entry maps us before and after.
    401 *
    402 * r3 = first entry to write
    403 * r4 = number of entries to write
    404 * r5 = temporary tlb entry (0 means no switch to AS1)
    405 */
    406_GLOBAL(loadcam_multi)
    407	mflr	r8
    408	/* Don't switch to AS=1 if already there */
    409	mfmsr	r11
    410	andi.	r11,r11,MSR_IS
    411	bne	10f
    412	mr.	r12, r5
    413	beq	10f
    414
    415	/*
    416	 * Set up temporary TLB entry that is the same as what we're
    417	 * running from, but in AS=1.
    418	 */
    419	bcl	20,31,$+4
    4201:	mflr	r6
    421	tlbsx	0,r8
    422	mfspr	r6,SPRN_MAS1
    423	ori	r6,r6,MAS1_TS
    424	mtspr	SPRN_MAS1,r6
    425	mfspr	r6,SPRN_MAS0
    426	rlwimi	r6,r5,MAS0_ESEL_SHIFT,MAS0_ESEL_MASK
    427	mr	r7,r5
    428	mtspr	SPRN_MAS0,r6
    429	isync
    430	tlbwe
    431	isync
    432
    433	/* Switch to AS=1 */
    434	mfmsr	r6
    435	ori	r6,r6,MSR_IS|MSR_DS
    436	mtmsr	r6
    437	isync
    438
    43910:
    440	mr	r9,r3
    441	add	r10,r3,r4
    4422:	bl	loadcam_entry
    443	addi	r9,r9,1
    444	cmpw	r9,r10
    445	mr	r3,r9
    446	blt	2b
    447
    448	/* Don't return to AS=0 if we were in AS=1 at function start */
    449	andi.	r11,r11,MSR_IS
    450	bne	3f
    451	cmpwi	r12, 0
    452	beq	3f
    453
    454	/* Return to AS=0 and clear the temporary entry */
    455	mfmsr	r6
    456	rlwinm.	r6,r6,0,~(MSR_IS|MSR_DS)
    457	mtmsr	r6
    458	isync
    459
    460	li	r6,0
    461	mtspr	SPRN_MAS1,r6
    462	rlwinm	r6,r7,MAS0_ESEL_SHIFT,MAS0_ESEL_MASK
    463	oris	r6,r6,MAS0_TLBSEL(1)@h
    464	mtspr	SPRN_MAS0,r6
    465	isync
    466	tlbwe
    467	isync
    468
    4693:
    470	mtlr	r8
    471	blr
    472#endif