xref: /openbmc/linux/arch/csky/mm/tlb.c (revision 3e30a927)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
3 
4 #include <linux/init.h>
5 #include <linux/mm.h>
6 #include <linux/module.h>
7 #include <linux/sched.h>
8 
9 #include <asm/mmu_context.h>
10 #include <asm/pgtable.h>
11 #include <asm/setup.h>
12 
13 /*
14  * One C-SKY MMU TLB entry contain two PFN/page entry, ie:
15  * 1VPN -> 2PFN
16  */
17 #define TLB_ENTRY_SIZE		(PAGE_SIZE * 2)
18 #define TLB_ENTRY_SIZE_MASK	(PAGE_MASK << 1)
19 
20 void flush_tlb_all(void)
21 {
22 	tlb_invalid_all();
23 }
24 
25 void flush_tlb_mm(struct mm_struct *mm)
26 {
27 #ifdef CONFIG_CPU_HAS_TLBI
28 	asm volatile("tlbi.asids %0"::"r"(cpu_asid(mm)));
29 #else
30 	tlb_invalid_all();
31 #endif
32 }
33 
34 /*
35  * MMU operation regs only could invalid tlb entry in jtlb and we
36  * need change asid field to invalid I-utlb & D-utlb.
37  */
38 #ifndef CONFIG_CPU_HAS_TLBI
39 #define restore_asid_inv_utlb(oldpid, newpid) \
40 do { \
41 	if (oldpid == newpid) \
42 		write_mmu_entryhi(oldpid + 1); \
43 	write_mmu_entryhi(oldpid); \
44 } while (0)
45 #endif
46 
47 void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
48 			unsigned long end)
49 {
50 	unsigned long newpid = cpu_asid(vma->vm_mm);
51 
52 	start &= TLB_ENTRY_SIZE_MASK;
53 	end   += TLB_ENTRY_SIZE - 1;
54 	end   &= TLB_ENTRY_SIZE_MASK;
55 
56 #ifdef CONFIG_CPU_HAS_TLBI
57 	while (start < end) {
58 		asm volatile("tlbi.vas %0"::"r"(start | newpid));
59 		start += 2*PAGE_SIZE;
60 	}
61 	sync_is();
62 #else
63 	{
64 	unsigned long flags, oldpid;
65 
66 	local_irq_save(flags);
67 	oldpid = read_mmu_entryhi() & ASID_MASK;
68 	while (start < end) {
69 		int idx;
70 
71 		write_mmu_entryhi(start | newpid);
72 		start += 2*PAGE_SIZE;
73 		tlb_probe();
74 		idx = read_mmu_index();
75 		if (idx >= 0)
76 			tlb_invalid_indexed();
77 	}
78 	restore_asid_inv_utlb(oldpid, newpid);
79 	local_irq_restore(flags);
80 	}
81 #endif
82 }
83 
84 void flush_tlb_kernel_range(unsigned long start, unsigned long end)
85 {
86 	start &= TLB_ENTRY_SIZE_MASK;
87 	end   += TLB_ENTRY_SIZE - 1;
88 	end   &= TLB_ENTRY_SIZE_MASK;
89 
90 #ifdef CONFIG_CPU_HAS_TLBI
91 	while (start < end) {
92 		asm volatile("tlbi.vaas %0"::"r"(start));
93 		start += 2*PAGE_SIZE;
94 	}
95 	sync_is();
96 #else
97 	{
98 	unsigned long flags, oldpid;
99 
100 	local_irq_save(flags);
101 	oldpid = read_mmu_entryhi() & ASID_MASK;
102 	while (start < end) {
103 		int idx;
104 
105 		write_mmu_entryhi(start | oldpid);
106 		start += 2*PAGE_SIZE;
107 		tlb_probe();
108 		idx = read_mmu_index();
109 		if (idx >= 0)
110 			tlb_invalid_indexed();
111 	}
112 	restore_asid_inv_utlb(oldpid, oldpid);
113 	local_irq_restore(flags);
114 	}
115 #endif
116 }
117 
118 void flush_tlb_page(struct vm_area_struct *vma, unsigned long addr)
119 {
120 	int newpid = cpu_asid(vma->vm_mm);
121 
122 	addr &= TLB_ENTRY_SIZE_MASK;
123 
124 #ifdef CONFIG_CPU_HAS_TLBI
125 	asm volatile("tlbi.vas %0"::"r"(addr | newpid));
126 	sync_is();
127 #else
128 	{
129 	int oldpid, idx;
130 	unsigned long flags;
131 
132 	local_irq_save(flags);
133 	oldpid = read_mmu_entryhi() & ASID_MASK;
134 	write_mmu_entryhi(addr | newpid);
135 	tlb_probe();
136 	idx = read_mmu_index();
137 	if (idx >= 0)
138 		tlb_invalid_indexed();
139 
140 	restore_asid_inv_utlb(oldpid, newpid);
141 	local_irq_restore(flags);
142 	}
143 #endif
144 }
145 
146 void flush_tlb_one(unsigned long addr)
147 {
148 	addr &= TLB_ENTRY_SIZE_MASK;
149 
150 #ifdef CONFIG_CPU_HAS_TLBI
151 	asm volatile("tlbi.vaas %0"::"r"(addr));
152 	sync_is();
153 #else
154 	{
155 	int oldpid, idx;
156 	unsigned long flags;
157 
158 	local_irq_save(flags);
159 	oldpid = read_mmu_entryhi() & ASID_MASK;
160 	write_mmu_entryhi(addr | oldpid);
161 	tlb_probe();
162 	idx = read_mmu_index();
163 	if (idx >= 0)
164 		tlb_invalid_indexed();
165 
166 	restore_asid_inv_utlb(oldpid, oldpid);
167 	local_irq_restore(flags);
168 	}
169 #endif
170 }
171 EXPORT_SYMBOL(flush_tlb_one);
172