1 /*
2 * linux/arch/arm/kernel/smp_tlb.c
3 *
4 * Copyright (C) 2002 ARM Limited, All Rights Reserved.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10 #include <linux/preempt.h>
11 #include <linux/smp.h>
12 #include <linux/uaccess.h>
13
14 #include <asm/smp_plat.h>
15 #include <asm/tlbflush.h>
16 #include <asm/mmu_context.h>
17
18 /**********************************************************************/
19
20 /*
21 * TLB operations
22 */
23 struct tlb_args {
24 struct vm_area_struct *ta_vma;
25 unsigned long ta_start;
26 unsigned long ta_end;
27 };
28
ipi_flush_tlb_all(void * ignored)29 static inline void ipi_flush_tlb_all(void *ignored)
30 {
31 local_flush_tlb_all();
32 }
33
ipi_flush_tlb_mm(void * arg)34 static inline void ipi_flush_tlb_mm(void *arg)
35 {
36 struct mm_struct *mm = (struct mm_struct *)arg;
37
38 local_flush_tlb_mm(mm);
39 }
40
ipi_flush_tlb_page(void * arg)41 static inline void ipi_flush_tlb_page(void *arg)
42 {
43 struct tlb_args *ta = (struct tlb_args *)arg;
44 unsigned int __ua_flags = uaccess_save_and_enable();
45
46 local_flush_tlb_page(ta->ta_vma, ta->ta_start);
47
48 uaccess_restore(__ua_flags);
49 }
50
ipi_flush_tlb_kernel_page(void * arg)51 static inline void ipi_flush_tlb_kernel_page(void *arg)
52 {
53 struct tlb_args *ta = (struct tlb_args *)arg;
54
55 local_flush_tlb_kernel_page(ta->ta_start);
56 }
57
ipi_flush_tlb_range(void * arg)58 static inline void ipi_flush_tlb_range(void *arg)
59 {
60 struct tlb_args *ta = (struct tlb_args *)arg;
61 unsigned int __ua_flags = uaccess_save_and_enable();
62
63 local_flush_tlb_range(ta->ta_vma, ta->ta_start, ta->ta_end);
64
65 uaccess_restore(__ua_flags);
66 }
67
ipi_flush_tlb_kernel_range(void * arg)68 static inline void ipi_flush_tlb_kernel_range(void *arg)
69 {
70 struct tlb_args *ta = (struct tlb_args *)arg;
71
72 local_flush_tlb_kernel_range(ta->ta_start, ta->ta_end);
73 }
74
ipi_flush_bp_all(void * ignored)75 static inline void ipi_flush_bp_all(void *ignored)
76 {
77 local_flush_bp_all();
78 }
79
80 #ifdef CONFIG_ARM_ERRATA_798181
81 bool (*erratum_a15_798181_handler)(void);
82
erratum_a15_798181_partial(void)83 static bool erratum_a15_798181_partial(void)
84 {
85 asm("mcr p15, 0, %0, c8, c3, 1" : : "r" (0));
86 dsb(ish);
87 return false;
88 }
89
erratum_a15_798181_broadcast(void)90 static bool erratum_a15_798181_broadcast(void)
91 {
92 asm("mcr p15, 0, %0, c8, c3, 1" : : "r" (0));
93 dsb(ish);
94 return true;
95 }
96
erratum_a15_798181_init(void)97 void erratum_a15_798181_init(void)
98 {
99 unsigned int midr = read_cpuid_id();
100 unsigned int revidr = read_cpuid(CPUID_REVIDR);
101
102 /* Brahma-B15 r0p0..r0p2 affected
103 * Cortex-A15 r0p0..r3p3 w/o ECO fix affected
104 * Fixes applied to A15 with respect to the revision and revidr are:
105 *
106 * r0p0-r2p1: No fixes applied
107 * r2p2,r2p3:
108 * REVIDR[4]: 798181 Moving a virtual page that is being accessed
109 * by an active process can lead to unexpected behavior
110 * REVIDR[9]: Not defined
111 * r2p4,r3p0,r3p1,r3p2:
112 * REVIDR[4]: 798181 Moving a virtual page that is being accessed
113 * by an active process can lead to unexpected behavior
114 * REVIDR[9]: 798181 Moving a virtual page that is being accessed
115 * by an active process can lead to unexpected behavior
116 * - This is an update to a previously released ECO.
117 * r3p3:
118 * REVIDR[4]: Reserved
119 * REVIDR[9]: 798181 Moving a virtual page that is being accessed
120 * by an active process can lead to unexpected behavior
121 * - This is an update to a previously released ECO.
122 *
123 * Handling:
124 * REVIDR[9] set -> No WA
125 * REVIDR[4] set, REVIDR[9] cleared -> Partial WA
126 * Both cleared -> Full WA
127 */
128 if ((midr & 0xff0ffff0) == 0x420f00f0 && midr <= 0x420f00f2) {
129 erratum_a15_798181_handler = erratum_a15_798181_broadcast;
130 } else if ((midr & 0xff0ffff0) == 0x410fc0f0 && midr < 0x412fc0f2) {
131 erratum_a15_798181_handler = erratum_a15_798181_broadcast;
132 } else if ((midr & 0xff0ffff0) == 0x410fc0f0 && midr < 0x412fc0f4) {
133 if (revidr & 0x10)
134 erratum_a15_798181_handler =
135 erratum_a15_798181_partial;
136 else
137 erratum_a15_798181_handler =
138 erratum_a15_798181_broadcast;
139 } else if ((midr & 0xff0ffff0) == 0x410fc0f0 && midr < 0x413fc0f3) {
140 if ((revidr & 0x210) == 0)
141 erratum_a15_798181_handler =
142 erratum_a15_798181_broadcast;
143 else if (revidr & 0x10)
144 erratum_a15_798181_handler =
145 erratum_a15_798181_partial;
146 } else if ((midr & 0xff0ffff0) == 0x410fc0f0 && midr < 0x414fc0f0) {
147 if ((revidr & 0x200) == 0)
148 erratum_a15_798181_handler =
149 erratum_a15_798181_partial;
150 }
151 }
152 #endif
153
ipi_flush_tlb_a15_erratum(void * arg)154 static void ipi_flush_tlb_a15_erratum(void *arg)
155 {
156 dmb();
157 }
158
broadcast_tlb_a15_erratum(void)159 static void broadcast_tlb_a15_erratum(void)
160 {
161 if (!erratum_a15_798181())
162 return;
163
164 smp_call_function(ipi_flush_tlb_a15_erratum, NULL, 1);
165 }
166
broadcast_tlb_mm_a15_erratum(struct mm_struct * mm)167 static void broadcast_tlb_mm_a15_erratum(struct mm_struct *mm)
168 {
169 int this_cpu;
170 cpumask_t mask = { CPU_BITS_NONE };
171
172 if (!erratum_a15_798181())
173 return;
174
175 this_cpu = get_cpu();
176 a15_erratum_get_cpumask(this_cpu, mm, &mask);
177 smp_call_function_many(&mask, ipi_flush_tlb_a15_erratum, NULL, 1);
178 put_cpu();
179 }
180
flush_tlb_all(void)181 void flush_tlb_all(void)
182 {
183 if (tlb_ops_need_broadcast())
184 on_each_cpu(ipi_flush_tlb_all, NULL, 1);
185 else
186 __flush_tlb_all();
187 broadcast_tlb_a15_erratum();
188 }
189
flush_tlb_mm(struct mm_struct * mm)190 void flush_tlb_mm(struct mm_struct *mm)
191 {
192 if (tlb_ops_need_broadcast())
193 on_each_cpu_mask(mm_cpumask(mm), ipi_flush_tlb_mm, mm, 1);
194 else
195 __flush_tlb_mm(mm);
196 broadcast_tlb_mm_a15_erratum(mm);
197 }
198
flush_tlb_page(struct vm_area_struct * vma,unsigned long uaddr)199 void flush_tlb_page(struct vm_area_struct *vma, unsigned long uaddr)
200 {
201 if (tlb_ops_need_broadcast()) {
202 struct tlb_args ta;
203 ta.ta_vma = vma;
204 ta.ta_start = uaddr;
205 on_each_cpu_mask(mm_cpumask(vma->vm_mm), ipi_flush_tlb_page,
206 &ta, 1);
207 } else
208 __flush_tlb_page(vma, uaddr);
209 broadcast_tlb_mm_a15_erratum(vma->vm_mm);
210 }
211
flush_tlb_kernel_page(unsigned long kaddr)212 void flush_tlb_kernel_page(unsigned long kaddr)
213 {
214 if (tlb_ops_need_broadcast()) {
215 struct tlb_args ta;
216 ta.ta_start = kaddr;
217 on_each_cpu(ipi_flush_tlb_kernel_page, &ta, 1);
218 } else
219 __flush_tlb_kernel_page(kaddr);
220 broadcast_tlb_a15_erratum();
221 }
222
flush_tlb_range(struct vm_area_struct * vma,unsigned long start,unsigned long end)223 void flush_tlb_range(struct vm_area_struct *vma,
224 unsigned long start, unsigned long end)
225 {
226 if (tlb_ops_need_broadcast()) {
227 struct tlb_args ta;
228 ta.ta_vma = vma;
229 ta.ta_start = start;
230 ta.ta_end = end;
231 on_each_cpu_mask(mm_cpumask(vma->vm_mm), ipi_flush_tlb_range,
232 &ta, 1);
233 } else
234 local_flush_tlb_range(vma, start, end);
235 broadcast_tlb_mm_a15_erratum(vma->vm_mm);
236 }
237
flush_tlb_kernel_range(unsigned long start,unsigned long end)238 void flush_tlb_kernel_range(unsigned long start, unsigned long end)
239 {
240 if (tlb_ops_need_broadcast()) {
241 struct tlb_args ta;
242 ta.ta_start = start;
243 ta.ta_end = end;
244 on_each_cpu(ipi_flush_tlb_kernel_range, &ta, 1);
245 } else
246 local_flush_tlb_kernel_range(start, end);
247 broadcast_tlb_a15_erratum();
248 }
249
flush_bp_all(void)250 void flush_bp_all(void)
251 {
252 if (tlb_ops_need_broadcast())
253 on_each_cpu(ipi_flush_bp_all, NULL, 1);
254 else
255 __flush_bp_all();
256 }
257