[RFC 2/2] ARC: retire MMUv1 and MMUv2 support

From: vgupta
Date: Sun Aug 08 2021 - 20:00:37 EST

From: Vineet Gupta <vgupta@xxxxxxxxxxxx>

These were present in ancient ARC700 cores which don't seem to be
active in field anymore.

Removal helps cleanup code and remove the hack for
MMU_VER to MMU_V[3-4] conversion

Signed-off-by: Vineet Gupta <vgupta@xxxxxxxxxxxx>
---
arch/arc/Kconfig | 22 +----
arch/arc/include/asm/mmu.h | 22 +----
arch/arc/include/asm/pgtable.h | 26 +----
arch/arc/include/asm/tlb-mmu1.h | 101 --------------------
arch/arc/mm/cache.c | 110 +++------------------
arch/arc/mm/tlb.c | 163 ++++----------------------------
arch/arc/mm/tlbex.S | 10 +-
7 files changed, 42 insertions(+), 412 deletions(-)
delete mode 100644 arch/arc/include/asm/tlb-mmu1.h

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index 3015788a7094..0680b1de0fc3 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -265,32 +265,17 @@ config ARC_DCCM_BASE

choice
prompt "MMU Version"
- default ARC_MMU_V3 if ARC_CPU_770
- default ARC_MMU_V4 if ARC_CPU_HS
-
-if ISA_ARCOMPACT
-
-config ARC_MMU_V1
- bool "MMU v1"
- help
- Orig ARC700 MMU
-
-config ARC_MMU_V2
- bool "MMU v2"
- help
- Fixed the deficiency of v1 - possible thrashing in memcpy scenario
- when 2 D-TLB and 1 I-TLB entries index into same 2way set.
+ default ARC_MMU_V3 if ISA_ARCOMPACT
+ default ARC_MMU_V4 if ISA_ARCV2

config ARC_MMU_V3
bool "MMU v3"
- depends on ARC_CPU_770
+ depends on ISA_ARCOMPACT
help
Introduced with ARC700 4.10: New Features
Variable Page size (1k-16k), var JTLB size 128 x (2 or 4)
Shared Address Spaces (SASID)

-endif
-
config ARC_MMU_V4
bool "MMU v4"
depends on ISA_ARCV2
@@ -309,7 +294,6 @@ config ARC_PAGE_SIZE_8K

config ARC_PAGE_SIZE_16K
bool "16KB"
- depends on ARC_MMU_V3 || ARC_MMU_V4

config ARC_PAGE_SIZE_4K
bool "4KB"
diff --git a/arch/arc/include/asm/mmu.h b/arch/arc/include/asm/mmu.h
index 26b731d32a2b..a81d1975866a 100644
--- a/arch/arc/include/asm/mmu.h
+++ b/arch/arc/include/asm/mmu.h
@@ -10,19 +10,10 @@
#include <linux/threads.h> /* NR_CPUS */
#endif

-#if defined(CONFIG_ARC_MMU_V1)
-#define CONFIG_ARC_MMU_VER 1
-#elif defined(CONFIG_ARC_MMU_V2)
-#define CONFIG_ARC_MMU_VER 2
-#elif defined(CONFIG_ARC_MMU_V3)
-#define CONFIG_ARC_MMU_VER 3
-#elif defined(CONFIG_ARC_MMU_V4)
-#define CONFIG_ARC_MMU_VER 4
-#endif
-
/* MMU Management regs */
#define ARC_REG_MMU_BCR 0x06f
-#if (CONFIG_ARC_MMU_VER < 4)
+
+#ifdef CONFIG_ARC_MMU_V3
#define ARC_REG_TLBPD0 0x405
#define ARC_REG_TLBPD1 0x406
#define ARC_REG_TLBPD1HI 0 /* Dummy: allows code sharing with ARC700 */
@@ -52,7 +43,7 @@
/* Error code if probe fails */
#define TLB_LKUP_ERR 0x80000000

-#if (CONFIG_ARC_MMU_VER < 4)
+#ifdef CONFIG_ARC_MMU_V3
#define TLB_DUP_ERR (TLB_LKUP_ERR | 0x00000001)
#else
#define TLB_DUP_ERR (TLB_LKUP_ERR | 0x40000000)
@@ -63,15 +54,10 @@
#define TLBRead 0x2
#define TLBGetIndex 0x3
#define TLBProbe 0x4
-
-#if (CONFIG_ARC_MMU_VER >= 2)
#define TLBWriteNI 0x5 /* write JTLB without inv uTLBs */
#define TLBIVUTLB 0x6 /* explicitly inv uTLBs */
-#else
-#define TLBWriteNI TLBWrite /* Not present in hardware, fallback */
-#endif

-#if (CONFIG_ARC_MMU_VER >= 4)
+#ifdef CONFIG_ARC_MMU_V4
#define TLBInsertEntry 0x7
#define TLBDeleteEntry 0x8
#endif
diff --git a/arch/arc/include/asm/pgtable.h b/arch/arc/include/asm/pgtable.h
index 320cc0ae8a08..0c3e220bd2b4 100644
--- a/arch/arc/include/asm/pgtable.h
+++ b/arch/arc/include/asm/pgtable.h
@@ -35,7 +35,7 @@
#include <linux/bits.h>
#include <asm-generic/pgtable-nopmd.h>
#include <asm/page.h>
-#include <asm/mmu.h> /* to propagate CONFIG_ARC_MMU_VER <n> */
+#include <asm/mmu.h>

/**************************************************************************
* Page Table Flags
@@ -51,20 +51,6 @@
* (saves some bit shift ops in TLB Miss hdlrs)
*/

-#if (CONFIG_ARC_MMU_VER <= 2)
-
-#define _PAGE_ACCESSED (1<<1) /* Page is accessed (S) */
-#define _PAGE_CACHEABLE (1<<2) /* Page is cached (H) */
-#define _PAGE_EXECUTE (1<<3) /* Page has user execute perm (H) */
-#define _PAGE_WRITE (1<<4) /* Page has user write perm (H) */
-#define _PAGE_READ (1<<5) /* Page has user read perm (H) */
-#define _PAGE_DIRTY (1<<6) /* Page modified (dirty) (S) */
-#define _PAGE_SPECIAL (1<<7)
-#define _PAGE_GLOBAL (1<<8) /* Page is global (H) */
-#define _PAGE_PRESENT (1<<10) /* TLB entry is valid (H) */
-
-#else /* MMU v3 onwards */
-
#define _PAGE_CACHEABLE (1<<0) /* Page is cached (H) */
#define _PAGE_EXECUTE (1<<1) /* Page has user execute perm (H) */
#define _PAGE_WRITE (1<<2) /* Page has user write perm (H) */
@@ -73,23 +59,15 @@
#define _PAGE_DIRTY (1<<5) /* Page modified (dirty) (S) */
#define _PAGE_SPECIAL (1<<6)

-#if (CONFIG_ARC_MMU_VER >= 4)
-#define _PAGE_WTHRU (1<<7) /* Page cache mode write-thru (H) */
-#endif
-
#define _PAGE_GLOBAL (1<<8) /* Page is global (H) */
#define _PAGE_PRESENT (1<<9) /* TLB entry is valid (H) */

-#if (CONFIG_ARC_MMU_VER >= 4)
+#ifdef CONFIG_ARC_MMU_V4
#define _PAGE_HW_SZ (1<<10) /* Page Size indicator (H): 0 normal, 1 super */
#endif

#define _PAGE_SHARED_CODE (1<<11) /* Shared Code page with cmn vaddr
usable for shared TLB entries (H) */
-
-#define _PAGE_UNUSED_BIT (1<<12)
-#endif
-
/* vmalloc permissions */
#define _K_PAGE_PERMS (_PAGE_EXECUTE | _PAGE_WRITE | _PAGE_READ | \
_PAGE_GLOBAL | _PAGE_PRESENT)
diff --git a/arch/arc/include/asm/tlb-mmu1.h b/arch/arc/include/asm/tlb-mmu1.h
deleted file mode 100644
index a3083b36f5f4..000000000000
--- a/arch/arc/include/asm/tlb-mmu1.h
+++ /dev/null
@@ -1,101 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
- */
-
-#ifndef __ASM_TLB_MMU_V1_H__
-#define __ASM_TLB_MMU_V1_H__
-
-#include <asm/mmu.h>
-
-#if defined(__ASSEMBLY__) && (CONFIG_ARC_MMU_VER == 1)
-
-.macro TLB_WRITE_HEURISTICS
-
-#define JH_HACK1
-#undef JH_HACK2
-#undef JH_HACK3
-
-#ifdef JH_HACK3
-; Calculate set index for 2-way MMU
-; -avoiding use of GetIndex from MMU
-; and its unpleasant LFSR pseudo-random sequence
-;
-; r1 = TLBPD0 from TLB_RELOAD above
-;
-; -- jh_ex_way_set not cleared on startup
-; didn't want to change setup.c
-; hence extra instruction to clean
-;
-; -- should be in cache since in same line
-; as r0/r1 saves above
-;
-ld r0,[jh_ex_way_sel] ; victim pointer
-and r0,r0,1 ; clean
-xor.f r0,r0,1 ; flip
-st r0,[jh_ex_way_sel] ; store back
-asr r0,r1,12 ; get set # <<1, note bit 12=R=0
-or.nz r0,r0,1 ; set way bit
-and r0,r0,0xff ; clean
-sr r0,[ARC_REG_TLBINDEX]
-#endif
-
-#ifdef JH_HACK2
-; JH hack #2
-; Faster than hack #1 in non-thrash case, but hard-coded for 2-way MMU
-; Slower in thrash case (where it matters) because more code is executed
-; Inefficient due to two-register paradigm of this miss handler
-;
-/* r1 = data TLBPD0 at this point */
-lr r0,[eret] /* instruction address */
-xor r0,r0,r1 /* compare set # */
-and.f r0,r0,0x000fe000 /* 2-way MMU mask */
-bne 88f /* not in same set - no need to probe */
-
-lr r0,[eret] /* instruction address */
-and r0,r0,PAGE_MASK /* VPN of instruction address */
-; lr r1,[ARC_REG_TLBPD0] /* Data VPN+ASID - already in r1 from TLB_RELOAD*/
-and r1,r1,0xff /* Data ASID */
-or r0,r0,r1 /* Instruction address + Data ASID */
-
-lr r1,[ARC_REG_TLBPD0] /* save TLBPD0 containing data TLB*/
-sr r0,[ARC_REG_TLBPD0] /* write instruction address to TLBPD0 */
-sr TLBProbe, [ARC_REG_TLBCOMMAND] /* Look for instruction */
-lr r0,[ARC_REG_TLBINDEX] /* r0 = index where instruction is, if at all */
-sr r1,[ARC_REG_TLBPD0] /* restore TLBPD0 */
-
-xor r0,r0,1 /* flip bottom bit of data index */
-b.d 89f
-sr r0,[ARC_REG_TLBINDEX] /* and put it back */
-88:
-sr TLBGetIndex, [ARC_REG_TLBCOMMAND]
-89:
-#endif
-
-#ifdef JH_HACK1
-;
-; Always checks whether instruction will be kicked out by dtlb miss
-;
-mov_s r3, r1 ; save PD0 prepared by TLB_RELOAD in r3
-lr r0,[eret] /* instruction address */
-and r0,r0,PAGE_MASK /* VPN of instruction address */
-bmsk r1,r3,7 /* Data ASID, bits 7-0 */
-or_s r0,r0,r1 /* Instruction address + Data ASID */
-
-sr r0,[ARC_REG_TLBPD0] /* write instruction address to TLBPD0 */
-sr TLBProbe, [ARC_REG_TLBCOMMAND] /* Look for instruction */
-lr r0,[ARC_REG_TLBINDEX] /* r0 = index where instruction is, if at all */
-sr r3,[ARC_REG_TLBPD0] /* restore TLBPD0 */
-
-sr TLBGetIndex, [ARC_REG_TLBCOMMAND]
-lr r1,[ARC_REG_TLBINDEX] /* r1 = index where MMU wants to put data */
-cmp r0,r1 /* if no match on indices, go around */
-xor.eq r1,r1,1 /* flip bottom bit of data index */
-sr r1,[ARC_REG_TLBINDEX] /* and put it back */
-#endif
-
-.endm
-
-#endif
-
-#endif
diff --git a/arch/arc/mm/cache.c b/arch/arc/mm/cache.c
index a2fbea3ee07c..0de1b87ba438 100644
--- a/arch/arc/mm/cache.c
+++ b/arch/arc/mm/cache.c
@@ -205,93 +205,24 @@ void read_decode_cache_bcr(void)
#define OP_INV_IC 0x4

/*
- * I-Cache Aliasing in ARC700 VIPT caches (MMU v1-v3)
+ * Cache Flush programming model
*
- * ARC VIPT I-cache uses vaddr to index into cache and paddr to match the tag.
- * The orig Cache Management Module "CDU" only required paddr to invalidate a
- * certain line since it sufficed as index in Non-Aliasing VIPT cache-geometry.
- * Infact for distinct V1,V2,P: all of {V1-P},{V2-P},{P-P} would end up fetching
- * the exact same line.
+ * ARC700 MMUv3 I$ and D$ are both VIPT and can potentially alias.
+ * Programming model requires both paddr and vaddr irrespecive of alising
+ * considerations:
+ * - vaddr in {I,D}C_IV?L
+ * - paddr in {I,D}C_PTAG
*
- * However for larger Caches (way-size > page-size) - i.e. in Aliasing config,
- * paddr alone could not be used to correctly index the cache.
+ * In HS38x (MMUv4), D$ is PIPT, I$ is VIPT and can still alias.
+ * Programming model is different for alising vs. non-alising I$
+ * - D$ / Non-alising I$: only paddr in {I,D}C_IV?L
+ * - Alising I$: same as ARC700 above (so MMUv3 routine used for MMUv4 I$)
*
- * ------------------
- * MMU v1/v2 (Fixed Page Size 8k)
- * ------------------
- * The solution was to provide CDU with these additonal vaddr bits. These
- * would be bits [x:13], x would depend on cache-geometry, 13 comes from
- * standard page size of 8k.
- * H/w folks chose [17:13] to be a future safe range, and moreso these 5 bits
- * of vaddr could easily be "stuffed" in the paddr as bits [4:0] since the
- * orig 5 bits of paddr were anyways ignored by CDU line ops, as they
- * represent the offset within cache-line. The adv of using this "clumsy"
- * interface for additional info was no new reg was needed in CDU programming
- * model.
- *
- * 17:13 represented the max num of bits passable, actual bits needed were
- * fewer, based on the num-of-aliases possible.
- * -for 2 alias possibility, only bit 13 needed (32K cache)
- * -for 4 alias possibility, bits 14:13 needed (64K cache)
- *
- * ------------------
- * MMU v3
- * ------------------
- * This ver of MMU supports variable page sizes (1k-16k): although Linux will
- * only support 8k (default), 16k and 4k.
- * However from hardware perspective, smaller page sizes aggravate aliasing
- * meaning more vaddr bits needed to disambiguate the cache-line-op ;
- * the existing scheme of piggybacking won't work for certain configurations.
- * Two new registers IC_PTAG and DC_PTAG inttoduced.
- * "tag" bits are provided in PTAG, index bits in existing IVIL/IVDL/FLDL regs
+ * - If PAE40 is enabled, independent of aliasing considerations, the higher
+ * bits needs to be written into PTAG_HI
*/

static inline
-void __cache_line_loop_v2(phys_addr_t paddr, unsigned long vaddr,
- unsigned long sz, const int op, const int full_page)
-{
- unsigned int aux_cmd;
- int num_lines;
-
- if (op == OP_INV_IC) {
- aux_cmd = ARC_REG_IC_IVIL;
- } else {
- /* d$ cmd: INV (discard or wback-n-discard) OR FLUSH (wback) */
- aux_cmd = op & OP_INV ? ARC_REG_DC_IVDL : ARC_REG_DC_FLDL;
- }
-
- /* Ensure we properly floor/ceil the non-line aligned/sized requests
- * and have @paddr - aligned to cache line and integral @num_lines.
- * This however can be avoided for page sized since:
- * -@paddr will be cache-line aligned already (being page aligned)
- * -@sz will be integral multiple of line size (being page sized).
- */
- if (!full_page) {
- sz += paddr & ~CACHE_LINE_MASK;
- paddr &= CACHE_LINE_MASK;
- vaddr &= CACHE_LINE_MASK;
- }
-
- num_lines = DIV_ROUND_UP(sz, L1_CACHE_BYTES);
-
- /* MMUv2 and before: paddr contains stuffed vaddrs bits */
- paddr |= (vaddr >> PAGE_SHIFT) & 0x1F;
-
- while (num_lines-- > 0) {
- write_aux_reg(aux_cmd, paddr);
- paddr += L1_CACHE_BYTES;
- }
-}
-
-/*
- * For ARC700 MMUv3 I-cache and D-cache flushes
- * - ARC700 programming model requires paddr and vaddr be passed in seperate
- * AUX registers (*_IV*L and *_PTAG respectively) irrespective of whether the
- * caches actually alias or not.
- * - For HS38, only the aliasing I-cache configuration uses the PTAG reg
- * (non aliasing I-cache version doesn't; while D-cache can't possibly alias)
- */
-static inline
void __cache_line_loop_v3(phys_addr_t paddr, unsigned long vaddr,
unsigned long sz, const int op, const int full_page)
{
@@ -350,17 +281,6 @@ void __cache_line_loop_v3(phys_addr_t paddr, unsigned long vaddr,
#ifndef USE_RGN_FLSH

/*
- * In HS38x (MMU v4), I-cache is VIPT (can alias), D-cache is PIPT
- * Here's how cache ops are implemented
- *
- * - D-cache: only paddr needed (in DC_IVDL/DC_FLDL)
- * - I-cache Non Aliasing: Despite VIPT, only paddr needed (in IC_IVIL)
- * - I-cache Aliasing: Both vaddr and paddr needed (in IC_IVIL, IC_PTAG
- * respectively, similar to MMU v3 programming model, hence
- * __cache_line_loop_v3() is used)
- *
- * If PAE40 is enabled, independent of aliasing considerations, the higher bits
- * needs to be written into PTAG_HI
*/
static inline
void __cache_line_loop_v4(phys_addr_t paddr, unsigned long vaddr,
@@ -460,11 +380,9 @@ void __cache_line_loop_v4(phys_addr_t paddr, unsigned long vaddr,

#endif

-#if (CONFIG_ARC_MMU_VER < 3)
-#define __cache_line_loop __cache_line_loop_v2
-#elif (CONFIG_ARC_MMU_VER == 3)
+#ifdef CONFIG_ARC_MMU_V3
#define __cache_line_loop __cache_line_loop_v3
-#elif (CONFIG_ARC_MMU_VER > 3)
+#else
#define __cache_line_loop __cache_line_loop_v4
#endif

diff --git a/arch/arc/mm/tlb.c b/arch/arc/mm/tlb.c
index 9c7c68247289..8696829d37c0 100644
--- a/arch/arc/mm/tlb.c
+++ b/arch/arc/mm/tlb.c
@@ -1,51 +1,9 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
- * TLB Management (flush/create/diagnostics) for ARC700
+ * TLB Management (flush/create/diagnostics) for MMUv3 and MMUv4
*
* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
*
- * vineetg: Aug 2011
- * -Reintroduce duplicate PD fixup - some customer chips still have the issue
- *
- * vineetg: May 2011
- * -No need to flush_cache_page( ) for each call to update_mmu_cache()
- * some of the LMBench tests improved amazingly
- * = page-fault thrice as fast (75 usec to 28 usec)
- * = mmap twice as fast (9.6 msec to 4.6 msec),
- * = fork (5.3 msec to 3.7 msec)
- *
- * vineetg: April 2011 :
- * -MMU v3: PD{0,1} bits layout changed: They don't overlap anymore,
- * helps avoid a shift when preparing PD0 from PTE
- *
- * vineetg: April 2011 : Preparing for MMU V3
- * -MMU v2/v3 BCRs decoded differently
- * -Remove TLB_SIZE hardcoding as it's variable now: 256 or 512
- * -tlb_entry_erase( ) can be void
- * -local_flush_tlb_range( ):
- * = need not "ceil" @end
- * = walks MMU only if range spans < 32 entries, as opposed to 256
- *
- * Vineetg: Sept 10th 2008
- * -Changes related to MMU v2 (Rel 4.8)
- *
- * Vineetg: Aug 29th 2008
- * -In TLB Flush operations (Metal Fix MMU) there is a explicit command to
- * flush Micro-TLBS. If TLB Index Reg is invalid prior to TLBIVUTLB cmd,
- * it fails. Thus need to load it with ANY valid value before invoking
- * TLBIVUTLB cmd
- *
- * Vineetg: Aug 21th 2008:
- * -Reduced the duration of IRQ lockouts in TLB Flush routines
- * -Multiple copies of TLB erase code separated into a "single" function
- * -In TLB Flush routines, interrupt disabling moved UP to retrieve ASID
- * in interrupt-safe region.
- *
- * Vineetg: April 23rd Bug #93131
- * Problem: tlb_flush_kernel_range() doesn't do anything if the range to
- * flush is more than the size of TLB itself.
- *
- * Rahul Trivedi : Codito Technologies 2004
*/

#include <linux/module.h>
@@ -57,47 +15,6 @@
#include <asm/mmu_context.h>
#include <asm/mmu.h>

-/* Need for ARC MMU v2
- *
- * ARC700 MMU-v1 had a Joint-TLB for Code and Data and is 2 way set-assoc.
- * For a memcpy operation with 3 players (src/dst/code) such that all 3 pages
- * map into same set, there would be contention for the 2 ways causing severe
- * Thrashing.
- *
- * Although J-TLB is 2 way set assoc, ARC700 caches J-TLB into uTLBS which has
- * much higher associativity. u-D-TLB is 8 ways, u-I-TLB is 4 ways.
- * Given this, the thrashing problem should never happen because once the 3
- * J-TLB entries are created (even though 3rd will knock out one of the prev
- * two), the u-D-TLB and u-I-TLB will have what is required to accomplish memcpy
- *
- * Yet we still see the Thrashing because a J-TLB Write cause flush of u-TLBs.
- * This is a simple design for keeping them in sync. So what do we do?
- * The solution which James came up was pretty neat. It utilised the assoc
- * of uTLBs by not invalidating always but only when absolutely necessary.
- *
- * - Existing TLB commands work as before
- * - New command (TLBWriteNI) for TLB write without clearing uTLBs
- * - New command (TLBIVUTLB) to invalidate uTLBs.
- *
- * The uTLBs need only be invalidated when pages are being removed from the
- * OS page table. If a 'victim' TLB entry is being overwritten in the main TLB
- * as a result of a miss, the removed entry is still allowed to exist in the
- * uTLBs as it is still valid and present in the OS page table. This allows the
- * full associativity of the uTLBs to hide the limited associativity of the main
- * TLB.
- *
- * During a miss handler, the new "TLBWriteNI" command is used to load
- * entries without clearing the uTLBs.
- *
- * When the OS page table is updated, TLB entries that may be associated with a
- * removed page are removed (flushed) from the TLB using TLBWrite. In this
- * circumstance, the uTLBs must also be cleared. This is done by using the
- * existing TLBWrite command. An explicit IVUTLB is also required for those
- * corner cases when TLBWrite was not executed at all because the corresp
- * J-TLB entry got evicted/replaced.
- */
-
-
/* A copy of the ASID from the PID reg is kept in asid_cache */
DEFINE_PER_CPU(unsigned int, asid_cache) = MM_CTXT_FIRST_CYCLE;

@@ -120,32 +37,10 @@ static inline void __tlb_entry_erase(void)

static void utlb_invalidate(void)
{
-#if (CONFIG_ARC_MMU_VER >= 2)
-
-#if (CONFIG_ARC_MMU_VER == 2)
- /* MMU v2 introduced the uTLB Flush command.
- * There was however an obscure hardware bug, where uTLB flush would
- * fail when a prior probe for J-TLB (both totally unrelated) would
- * return lkup err - because the entry didn't exist in MMU.
- * The Workaround was to set Index reg with some valid value, prior to
- * flush. This was fixed in MMU v3
- */
- unsigned int idx;
-
- /* make sure INDEX Reg is valid */
- idx = read_aux_reg(ARC_REG_TLBINDEX);
-
- /* If not write some dummy val */
- if (unlikely(idx & TLB_LKUP_ERR))
- write_aux_reg(ARC_REG_TLBINDEX, 0xa);
-#endif
-
write_aux_reg(ARC_REG_TLBCOMMAND, TLBIVUTLB);
-#endif
-
}

-#if (CONFIG_ARC_MMU_VER < 4)
+#ifdef CONFIG_ARC_MMU_V3

static inline unsigned int tlb_entry_lkup(unsigned long vaddr_n_asid)
{
@@ -206,7 +101,7 @@ static void tlb_entry_insert(unsigned int pd0, pte_t pd1)
write_aux_reg(ARC_REG_TLBCOMMAND, TLBWrite);
}

-#else /* CONFIG_ARC_MMU_VER >= 4) */
+#else /* MMUv4 */

static void tlb_entry_erase(unsigned int vaddr_n_asid)
{
@@ -706,14 +601,6 @@ void read_decode_mmu_bcr(void)
{
struct cpuinfo_arc_mmu *mmu = &cpuinfo_arc700[smp_processor_id()].mmu;
unsigned int tmp;
- struct bcr_mmu_1_2 {
-#ifdef CONFIG_CPU_BIG_ENDIAN
- unsigned int ver:8, ways:4, sets:4, u_itlb:8, u_dtlb:8;
-#else
- unsigned int u_dtlb:8, u_itlb:8, sets:4, ways:4, ver:8;
-#endif
- } *mmu2;
-
struct bcr_mmu_3 {
#ifdef CONFIG_CPU_BIG_ENDIAN
unsigned int ver:8, ways:4, sets:4, res:3, sasid:1, pg_sz:4,
@@ -738,23 +625,14 @@ void read_decode_mmu_bcr(void)
tmp = read_aux_reg(ARC_REG_MMU_BCR);
mmu->ver = (tmp >> 24);

- if (is_isa_arcompact()) {
- if (mmu->ver <= 2) {
- mmu2 = (struct bcr_mmu_1_2 *)&tmp;
- mmu->pg_sz_k = TO_KB(0x2000);
- mmu->sets = 1 << mmu2->sets;
- mmu->ways = 1 << mmu2->ways;
- mmu->u_dtlb = mmu2->u_dtlb;
- mmu->u_itlb = mmu2->u_itlb;
- } else {
- mmu3 = (struct bcr_mmu_3 *)&tmp;
- mmu->pg_sz_k = 1 << (mmu3->pg_sz - 1);
- mmu->sets = 1 << mmu3->sets;
- mmu->ways = 1 << mmu3->ways;
- mmu->u_dtlb = mmu3->u_dtlb;
- mmu->u_itlb = mmu3->u_itlb;
- mmu->sasid = mmu3->sasid;
- }
+ if (is_isa_arcompact() && mmu->ver == 3) {
+ mmu3 = (struct bcr_mmu_3 *)&tmp;
+ mmu->pg_sz_k = 1 << (mmu3->pg_sz - 1);
+ mmu->sets = 1 << mmu3->sets;
+ mmu->ways = 1 << mmu3->ways;
+ mmu->u_dtlb = mmu3->u_dtlb;
+ mmu->u_itlb = mmu3->u_itlb;
+ mmu->sasid = mmu3->sasid;
} else {
mmu4 = (struct bcr_mmu_4 *)&tmp;
mmu->pg_sz_k = 1 << (mmu4->sz0 - 1);
@@ -815,22 +693,17 @@ void arc_mmu_init(void)

/*
* Ensure that MMU features assumed by kernel exist in hardware.
- * For older ARC700 cpus, it has to be exact match, since the MMU
- * revisions were not backwards compatible (MMUv3 TLB layout changed
- * so even if kernel for v2 didn't use any new cmds of v3, it would
- * still not work.
- * For HS cpus, MMUv4 was baseline and v5 is backwards compatible
- * (will run older software).
+ * - For older ARC700 cpus, only v3 supported
+ * - For HS cpus, v4 was baseline and v5 is backwards compatible
+ * (will run older software).
*/
- if (is_isa_arcompact() && mmu->ver == CONFIG_ARC_MMU_VER)
+ if (is_isa_arcompact() && mmu->ver == 3)
compat = 1;
- else if (is_isa_arcv2() && mmu->ver >= CONFIG_ARC_MMU_VER)
+ else if (is_isa_arcv2() && mmu->ver >= 4)
compat = 1;

- if (!compat) {
- panic("MMU ver %d doesn't match kernel built for %d...\n",
- mmu->ver, CONFIG_ARC_MMU_VER);
- }
+ if (!compat)
+ panic("MMU ver %d doesn't match kernel built for\n", mmu->ver);

if (mmu->pg_sz_k != TO_KB(PAGE_SIZE))
panic("MMU pg size != PAGE_SIZE (%luk)\n", TO_KB(PAGE_SIZE));
diff --git a/arch/arc/mm/tlbex.S b/arch/arc/mm/tlbex.S
index 062fae46c3f8..96c3a5de9dd4 100644
--- a/arch/arc/mm/tlbex.S
+++ b/arch/arc/mm/tlbex.S
@@ -39,7 +39,6 @@
#include <asm/arcregs.h>
#include <asm/cache.h>
#include <asm/processor.h>
-#include <asm/tlb-mmu1.h>

#ifdef CONFIG_ISA_ARCOMPACT
;-----------------------------------------------------------------
@@ -279,7 +278,7 @@ ex_saved_reg1:
; Commit the TLB entry into MMU

.macro COMMIT_ENTRY_TO_MMU
-#if (CONFIG_ARC_MMU_VER < 4)
+#ifdef CONFIG_ARC_MMU_V3

/* Get free TLB slot: Set = computed from vaddr, way = random */
sr TLBGetIndex, [ARC_REG_TLBCOMMAND]
@@ -375,13 +374,6 @@ ENTRY(EV_TLBMissD)

CONV_PTE_TO_TLB

-#if (CONFIG_ARC_MMU_VER == 1)
- ; MMU with 2 way set assoc J-TLB, needs some help in pathetic case of
- ; memcpy where 3 parties contend for 2 ways, ensuing a livelock.
- ; But only for old MMU or one with Metal Fix
- TLB_WRITE_HEURISTICS
-#endif
-
COMMIT_ENTRY_TO_MMU
TLBMISS_RESTORE_REGS
EV_TLBMissD_fast_ret: ; additional label for VDK OS-kit instrumentation
--
2.25.1