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Diffstat (limited to 'arch/powerpc/include/asm/nohash/32/pte-40x.h')
-rw-r--r--arch/powerpc/include/asm/nohash/32/pte-40x.h73
1 files changed, 0 insertions, 73 deletions
diff --git a/arch/powerpc/include/asm/nohash/32/pte-40x.h b/arch/powerpc/include/asm/nohash/32/pte-40x.h
deleted file mode 100644
index d759cfd74754..000000000000
--- a/arch/powerpc/include/asm/nohash/32/pte-40x.h
+++ /dev/null
@@ -1,73 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_POWERPC_NOHASH_32_PTE_40x_H
-#define _ASM_POWERPC_NOHASH_32_PTE_40x_H
-#ifdef __KERNEL__
-
-/*
- * At present, all PowerPC 400-class processors share a similar TLB
- * architecture. The instruction and data sides share a unified,
- * 64-entry, fully-associative TLB which is maintained totally under
- * software control. In addition, the instruction side has a
- * hardware-managed, 4-entry, fully-associative TLB which serves as a
- * first level to the shared TLB. These two TLBs are known as the UTLB
- * and ITLB, respectively (see "mmu.h" for definitions).
- *
- * There are several potential gotchas here. The 40x hardware TLBLO
- * field looks like this:
- *
- * 0 1 2 3 4 ... 18 19 20 21 22 23 24 25 26 27 28 29 30 31
- * RPN..................... 0 0 EX WR ZSEL....... W I M G
- *
- * Where possible we make the Linux PTE bits match up with this
- *
- * - bits 20 and 21 must be cleared, because we use 4k pages (40x can
- * support down to 1k pages), this is done in the TLBMiss exception
- * handler.
- * - We use only zones 0 (for kernel pages) and 1 (for user pages)
- * of the 16 available. Bit 24-26 of the TLB are cleared in the TLB
- * miss handler. Bit 27 is PAGE_USER, thus selecting the correct
- * zone.
- * - PRESENT *must* be in the bottom two bits because swap PTEs
- * use the top 30 bits. Because 40x doesn't support SMP anyway, M is
- * irrelevant so we borrow it for PAGE_PRESENT. Bit 30
- * is cleared in the TLB miss handler before the TLB entry is loaded.
- * - All other bits of the PTE are loaded into TLBLO without
- * modification, leaving us only the bits 20, 21, 24, 25, 26, 30 for
- * software PTE bits. We actually use bits 21, 24, 25, and
- * 30 respectively for the software bits: ACCESSED, DIRTY, RW, and
- * PRESENT.
- */
-
-#define _PAGE_GUARDED 0x001 /* G: page is guarded from prefetch */
-#define _PAGE_PRESENT 0x002 /* software: PTE contains a translation */
-#define _PAGE_NO_CACHE 0x004 /* I: caching is inhibited */
-#define _PAGE_WRITETHRU 0x008 /* W: caching is write-through */
-#define _PAGE_READ 0x010 /* software: read permission */
-#define _PAGE_SPECIAL 0x020 /* software: Special page */
-#define _PAGE_DIRTY 0x080 /* software: dirty page */
-#define _PAGE_WRITE 0x100 /* hardware: WR, anded with dirty in exception */
-#define _PAGE_EXEC 0x200 /* hardware: EX permission */
-#define _PAGE_ACCESSED 0x400 /* software: R: page referenced */
-
-/* No page size encoding in the linux PTE */
-#define _PAGE_PSIZE 0
-
-/* cache related flags non existing on 40x */
-#define _PAGE_COHERENT 0
-
-#define _PMD_PRESENT 0x400 /* PMD points to page of PTEs */
-#define _PMD_PRESENT_MASK _PMD_PRESENT
-#define _PMD_BAD 0x802
-#define _PMD_SIZE_4M 0x0c0
-#define _PMD_SIZE_16M 0x0e0
-#define _PMD_USER 0
-
-#define _PTE_NONE_MASK 0
-
-#define _PAGE_BASE_NC (_PAGE_PRESENT | _PAGE_ACCESSED)
-#define _PAGE_BASE (_PAGE_BASE_NC)
-
-#include <asm/pgtable-masks.h>
-
-#endif /* __KERNEL__ */
-#endif /* _ASM_POWERPC_NOHASH_32_PTE_40x_H */