xref: /openbmc/linux/arch/sh/mm/tlb-pteaex.c (revision 588b48ca)
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/mmu_context.h>
16 #include <asm/cacheflush.h>
17 
18 void __update_tlb(struct vm_area_struct *vma, unsigned long address, pte_t pte)
19 {
20 	unsigned long flags, pteval, vpn;
21 
22 	/*
23 	 * Handle debugger faulting in for debugee.
24 	 */
25 	if (vma && current->active_mm != vma->vm_mm)
26 		return;
27 
28 	local_irq_save(flags);
29 
30 	/* Set PTEH register */
31 	vpn = address & MMU_VPN_MASK;
32 	__raw_writel(vpn, MMU_PTEH);
33 
34 	/* Set PTEAEX */
35 	__raw_writel(get_asid(), MMU_PTEAEX);
36 
37 	pteval = pte.pte_low;
38 
39 	/* Set PTEA register */
40 #ifdef CONFIG_X2TLB
41 	/*
42 	 * For the extended mode TLB this is trivial, only the ESZ and
43 	 * EPR bits need to be written out to PTEA, with the remainder of
44 	 * the protection bits (with the exception of the compat-mode SZ
45 	 * and PR bits, which are cleared) being written out in PTEL.
46 	 */
47 	__raw_writel(pte.pte_high, MMU_PTEA);
48 #endif
49 
50 	/* Set PTEL register */
51 	pteval &= _PAGE_FLAGS_HARDWARE_MASK; /* drop software flags */
52 #ifdef CONFIG_CACHE_WRITETHROUGH
53 	pteval |= _PAGE_WT;
54 #endif
55 	/* conveniently, we want all the software flags to be 0 anyway */
56 	__raw_writel(pteval, MMU_PTEL);
57 
58 	/* Load the TLB */
59 	asm volatile("ldtlb": /* no output */ : /* no input */ : "memory");
60 	local_irq_restore(flags);
61 }
62 
63 /*
64  * While SH-X2 extended TLB mode splits out the memory-mapped I/UTLB
65  * data arrays, SH-X3 cores with PTEAEX split out the memory-mapped
66  * address arrays. In compat mode the second array is inaccessible, while
67  * in extended mode, the legacy 8-bit ASID field in address array 1 has
68  * undefined behaviour.
69  */
70 void local_flush_tlb_one(unsigned long asid, unsigned long page)
71 {
72 	jump_to_uncached();
73 	__raw_writel(page, MMU_UTLB_ADDRESS_ARRAY | MMU_PAGE_ASSOC_BIT);
74 	__raw_writel(asid, MMU_UTLB_ADDRESS_ARRAY2 | MMU_PAGE_ASSOC_BIT);
75 	__raw_writel(page, MMU_ITLB_ADDRESS_ARRAY | MMU_PAGE_ASSOC_BIT);
76 	__raw_writel(asid, MMU_ITLB_ADDRESS_ARRAY2 | MMU_PAGE_ASSOC_BIT);
77 	back_to_cached();
78 }
79 
80 void local_flush_tlb_all(void)
81 {
82 	unsigned long flags, status;
83 	int i;
84 
85 	/*
86 	 * Flush all the TLB.
87 	 */
88 	local_irq_save(flags);
89 	jump_to_uncached();
90 
91 	status = __raw_readl(MMUCR);
92 	status = ((status & MMUCR_URB) >> MMUCR_URB_SHIFT);
93 
94 	if (status == 0)
95 		status = MMUCR_URB_NENTRIES;
96 
97 	for (i = 0; i < status; i++)
98 		__raw_writel(0x0, MMU_UTLB_ADDRESS_ARRAY | (i << 8));
99 
100 	for (i = 0; i < 4; i++)
101 		__raw_writel(0x0, MMU_ITLB_ADDRESS_ARRAY | (i << 8));
102 
103 	back_to_cached();
104 	ctrl_barrier();
105 	local_irq_restore(flags);
106 }
107