xref: /linux/arch/sh/mm/tlb-sh4.c (revision 47902f3611b392209e2a412bf7ec02dca95e666d)
1 /*
2  * arch/sh/mm/tlb-sh4.c
3  *
4  * SH-4 specific TLB operations
5  *
6  * Copyright (C) 1999  Niibe Yutaka
7  * Copyright (C) 2002 - 2007 Paul Mundt
8  *
9  * Released under the terms of the GNU GPL v2.0.
10  */
11 #include <linux/kernel.h>
12 #include <linux/mm.h>
13 #include <linux/io.h>
14 #include <asm/system.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) | get_asid();
32 	__raw_writel(vpn, MMU_PTEH);
33 
34 	pteval = pte.pte_low;
35 
36 	/* Set PTEA register */
37 #ifdef CONFIG_X2TLB
38 	/*
39 	 * For the extended mode TLB this is trivial, only the ESZ and
40 	 * EPR bits need to be written out to PTEA, with the remainder of
41 	 * the protection bits (with the exception of the compat-mode SZ
42 	 * and PR bits, which are cleared) being written out in PTEL.
43 	 */
44 	__raw_writel(pte.pte_high, MMU_PTEA);
45 #else
46 	if (cpu_data->flags & CPU_HAS_PTEA) {
47 		/* The last 3 bits and the first one of pteval contains
48 		 * the PTEA timing control and space attribute bits
49 		 */
50 		__raw_writel(copy_ptea_attributes(pteval), MMU_PTEA);
51 	}
52 #endif
53 
54 	/* Set PTEL register */
55 	pteval &= _PAGE_FLAGS_HARDWARE_MASK; /* drop software flags */
56 #ifdef CONFIG_CACHE_WRITETHROUGH
57 	pteval |= _PAGE_WT;
58 #endif
59 	/* conveniently, we want all the software flags to be 0 anyway */
60 	__raw_writel(pteval, MMU_PTEL);
61 
62 	/* Load the TLB */
63 	asm volatile("ldtlb": /* no output */ : /* no input */ : "memory");
64 	local_irq_restore(flags);
65 }
66 
67 void local_flush_tlb_one(unsigned long asid, unsigned long page)
68 {
69 	unsigned long addr, data;
70 
71 	/*
72 	 * NOTE: PTEH.ASID should be set to this MM
73 	 *       _AND_ we need to write ASID to the array.
74 	 *
75 	 * It would be simple if we didn't need to set PTEH.ASID...
76 	 */
77 	addr = MMU_UTLB_ADDRESS_ARRAY | MMU_PAGE_ASSOC_BIT;
78 	data = page | asid; /* VALID bit is off */
79 	jump_to_uncached();
80 	__raw_writel(data, addr);
81 	back_to_cached();
82 }
83 
84 void local_flush_tlb_all(void)
85 {
86 	unsigned long flags, status;
87 	int i;
88 
89 	/*
90 	 * Flush all the TLB.
91 	 */
92 	local_irq_save(flags);
93 	jump_to_uncached();
94 
95 	status = __raw_readl(MMUCR);
96 	status = ((status & MMUCR_URB) >> MMUCR_URB_SHIFT);
97 
98 	if (status == 0)
99 		status = MMUCR_URB_NENTRIES;
100 
101 	for (i = 0; i < status; i++)
102 		__raw_writel(0x0, MMU_UTLB_ADDRESS_ARRAY | (i << 8));
103 
104 	for (i = 0; i < 4; i++)
105 		__raw_writel(0x0, MMU_ITLB_ADDRESS_ARRAY | (i << 8));
106 
107 	back_to_cached();
108 	ctrl_barrier();
109 	local_irq_restore(flags);
110 }
111