xref: /linux/arch/sh/mm/tlb-sh4.c (revision 0154ec71d597692a0d0682b19eac4b3adfb7f3dc)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * arch/sh/mm/tlb-sh4.c
4  *
5  * SH-4 specific TLB operations
6  *
7  * Copyright (C) 1999  Niibe Yutaka
8  * Copyright (C) 2002 - 2007 Paul Mundt
9  */
10 #include <linux/kernel.h>
11 #include <linux/mm.h>
12 #include <linux/io.h>
13 #include <asm/mmu_context.h>
14 #include <asm/cacheflush.h>
15 
16 void __update_tlb(struct vm_area_struct *vma, unsigned long address, pte_t pte)
17 {
18 	unsigned long flags, pteval, vpn;
19 
20 	/*
21 	 * Handle debugger faulting in for debugee.
22 	 */
23 	if (vma && current->active_mm != vma->vm_mm)
24 		return;
25 
26 	local_irq_save(flags);
27 
28 	/* Set PTEH register */
29 	vpn = (address & MMU_VPN_MASK) | get_asid();
30 	__raw_writel(vpn, MMU_PTEH);
31 
32 	pteval = pte.pte_low;
33 
34 	/* Set PTEA register */
35 #ifdef CONFIG_X2TLB
36 	/*
37 	 * For the extended mode TLB this is trivial, only the ESZ and
38 	 * EPR bits need to be written out to PTEA, with the remainder of
39 	 * the protection bits (with the exception of the compat-mode SZ
40 	 * and PR bits, which are cleared) being written out in PTEL.
41 	 */
42 	__raw_writel(pte.pte_high, MMU_PTEA);
43 #else
44 	if (cpu_data->flags & CPU_HAS_PTEA) {
45 		/* The last 3 bits and the first one of pteval contains
46 		 * the PTEA timing control and space attribute bits
47 		 */
48 		__raw_writel(copy_ptea_attributes(pteval), MMU_PTEA);
49 	}
50 #endif
51 
52 	/* Set PTEL register */
53 	pteval &= _PAGE_FLAGS_HARDWARE_MASK; /* drop software flags */
54 #ifdef CONFIG_CACHE_WRITETHROUGH
55 	pteval |= _PAGE_WT;
56 #endif
57 	/* conveniently, we want all the software flags to be 0 anyway */
58 	__raw_writel(pteval, MMU_PTEL);
59 
60 	/* Load the TLB */
61 	asm volatile("ldtlb": /* no output */ : /* no input */ : "memory");
62 	local_irq_restore(flags);
63 }
64 
65 void local_flush_tlb_one(unsigned long asid, unsigned long page)
66 {
67 	unsigned long addr, data;
68 
69 	/*
70 	 * NOTE: PTEH.ASID should be set to this MM
71 	 *       _AND_ we need to write ASID to the array.
72 	 *
73 	 * It would be simple if we didn't need to set PTEH.ASID...
74 	 */
75 	addr = MMU_UTLB_ADDRESS_ARRAY | MMU_PAGE_ASSOC_BIT;
76 	data = page | asid; /* VALID bit is off */
77 	jump_to_uncached();
78 	__raw_writel(data, addr);
79 	back_to_cached();
80 }
81 
82 void local_flush_tlb_all(void)
83 {
84 	unsigned long flags, status;
85 	int i;
86 
87 	/*
88 	 * Flush all the TLB.
89 	 */
90 	local_irq_save(flags);
91 	jump_to_uncached();
92 
93 	status = __raw_readl(MMUCR);
94 	status = ((status & MMUCR_URB) >> MMUCR_URB_SHIFT);
95 
96 	if (status == 0)
97 		status = MMUCR_URB_NENTRIES;
98 
99 	for (i = 0; i < status; i++)
100 		__raw_writel(0x0, MMU_UTLB_ADDRESS_ARRAY | (i << 8));
101 
102 	for (i = 0; i < 4; i++)
103 		__raw_writel(0x0, MMU_ITLB_ADDRESS_ARRAY | (i << 8));
104 
105 	back_to_cached();
106 	ctrl_barrier();
107 	local_irq_restore(flags);
108 }
109