xref: /openbmc/linux/arch/sh/mm/tlb-pteaex.c (revision fd589a8f)
1 /*
2  * arch/sh/mm/tlb-pteaex.c
3  *
4  * TLB operations for SH-X3 CPUs featuring PTE ASID Extensions.
5  *
6  * Copyright (C) 2009 Paul Mundt
7  *
8  * This file is subject to the terms and conditions of the GNU General Public
9  * License.  See the file "COPYING" in the main directory of this archive
10  * for more details.
11  */
12 #include <linux/kernel.h>
13 #include <linux/mm.h>
14 #include <linux/io.h>
15 #include <asm/system.h>
16 #include <asm/mmu_context.h>
17 #include <asm/cacheflush.h>
18 
19 void __update_tlb(struct vm_area_struct *vma, unsigned long address, pte_t pte)
20 {
21 	unsigned long flags, pteval, vpn;
22 
23 	/*
24 	 * Handle debugger faulting in for debugee.
25 	 */
26 	if (vma && current->active_mm != vma->vm_mm)
27 		return;
28 
29 	local_irq_save(flags);
30 
31 	/* Set PTEH register */
32 	vpn = address & MMU_VPN_MASK;
33 	__raw_writel(vpn, MMU_PTEH);
34 
35 	/* Set PTEAEX */
36 	__raw_writel(get_asid(), MMU_PTEAEX);
37 
38 	pteval = pte.pte_low;
39 
40 	/* Set PTEA register */
41 #ifdef CONFIG_X2TLB
42 	/*
43 	 * For the extended mode TLB this is trivial, only the ESZ and
44 	 * EPR bits need to be written out to PTEA, with the remainder of
45 	 * the protection bits (with the exception of the compat-mode SZ
46 	 * and PR bits, which are cleared) being written out in PTEL.
47 	 */
48 	__raw_writel(pte.pte_high, MMU_PTEA);
49 #endif
50 
51 	/* Set PTEL register */
52 	pteval &= _PAGE_FLAGS_HARDWARE_MASK; /* drop software flags */
53 #ifdef CONFIG_CACHE_WRITETHROUGH
54 	pteval |= _PAGE_WT;
55 #endif
56 	/* conveniently, we want all the software flags to be 0 anyway */
57 	__raw_writel(pteval, MMU_PTEL);
58 
59 	/* Load the TLB */
60 	asm volatile("ldtlb": /* no output */ : /* no input */ : "memory");
61 	local_irq_restore(flags);
62 }
63 
64 /*
65  * While SH-X2 extended TLB mode splits out the memory-mapped I/UTLB
66  * data arrays, SH-X3 cores with PTEAEX split out the memory-mapped
67  * address arrays. In compat mode the second array is inaccessible, while
68  * in extended mode, the legacy 8-bit ASID field in address array 1 has
69  * undefined behaviour.
70  */
71 void __uses_jump_to_uncached local_flush_tlb_one(unsigned long asid,
72 						 unsigned long page)
73 {
74 	jump_to_uncached();
75 	__raw_writel(page, MMU_UTLB_ADDRESS_ARRAY | MMU_PAGE_ASSOC_BIT);
76 	__raw_writel(asid, MMU_UTLB_ADDRESS_ARRAY2 | MMU_PAGE_ASSOC_BIT);
77 	back_to_cached();
78 }
79