xref: /openbmc/linux/arch/sh/mm/tlb-sh4.c (revision f3539c12)
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/mmu_context.h>
15 #include <asm/cacheflush.h>
16 
17 void __update_tlb(struct vm_area_struct *vma, unsigned long address, pte_t pte)
18 {
19 	unsigned long flags, pteval, vpn;
20 
21 	/*
22 	 * Handle debugger faulting in for debugee.
23 	 */
24 	if (vma && current->active_mm != vma->vm_mm)
25 		return;
26 
27 	local_irq_save(flags);
28 
29 	/* Set PTEH register */
30 	vpn = (address & MMU_VPN_MASK) | get_asid();
31 	__raw_writel(vpn, MMU_PTEH);
32 
33 	pteval = pte.pte_low;
34 
35 	/* Set PTEA register */
36 #ifdef CONFIG_X2TLB
37 	/*
38 	 * For the extended mode TLB this is trivial, only the ESZ and
39 	 * EPR bits need to be written out to PTEA, with the remainder of
40 	 * the protection bits (with the exception of the compat-mode SZ
41 	 * and PR bits, which are cleared) being written out in PTEL.
42 	 */
43 	__raw_writel(pte.pte_high, MMU_PTEA);
44 #else
45 	if (cpu_data->flags & CPU_HAS_PTEA) {
46 		/* The last 3 bits and the first one of pteval contains
47 		 * the PTEA timing control and space attribute bits
48 		 */
49 		__raw_writel(copy_ptea_attributes(pteval), MMU_PTEA);
50 	}
51 #endif
52 
53 	/* Set PTEL register */
54 	pteval &= _PAGE_FLAGS_HARDWARE_MASK; /* drop software flags */
55 #ifdef CONFIG_CACHE_WRITETHROUGH
56 	pteval |= _PAGE_WT;
57 #endif
58 	/* conveniently, we want all the software flags to be 0 anyway */
59 	__raw_writel(pteval, MMU_PTEL);
60 
61 	/* Load the TLB */
62 	asm volatile("ldtlb": /* no output */ : /* no input */ : "memory");
63 	local_irq_restore(flags);
64 }
65 
66 void local_flush_tlb_one(unsigned long asid, unsigned long page)
67 {
68 	unsigned long addr, data;
69 
70 	/*
71 	 * NOTE: PTEH.ASID should be set to this MM
72 	 *       _AND_ we need to write ASID to the array.
73 	 *
74 	 * It would be simple if we didn't need to set PTEH.ASID...
75 	 */
76 	addr = MMU_UTLB_ADDRESS_ARRAY | MMU_PAGE_ASSOC_BIT;
77 	data = page | asid; /* VALID bit is off */
78 	jump_to_uncached();
79 	__raw_writel(data, addr);
80 	back_to_cached();
81 }
82 
83 void local_flush_tlb_all(void)
84 {
85 	unsigned long flags, status;
86 	int i;
87 
88 	/*
89 	 * Flush all the TLB.
90 	 */
91 	local_irq_save(flags);
92 	jump_to_uncached();
93 
94 	status = __raw_readl(MMUCR);
95 	status = ((status & MMUCR_URB) >> MMUCR_URB_SHIFT);
96 
97 	if (status == 0)
98 		status = MMUCR_URB_NENTRIES;
99 
100 	for (i = 0; i < status; i++)
101 		__raw_writel(0x0, MMU_UTLB_ADDRESS_ARRAY | (i << 8));
102 
103 	for (i = 0; i < 4; i++)
104 		__raw_writel(0x0, MMU_ITLB_ADDRESS_ARRAY | (i << 8));
105 
106 	back_to_cached();
107 	ctrl_barrier();
108 	local_irq_restore(flags);
109 }
110