GNU Linux-libre 4.19.264-gnu1
[releases.git] / arch / arm / kernel / smp_tlb.c
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
29 static inline void ipi_flush_tlb_all(void *ignored)
30 {
31         local_flush_tlb_all();
32 }
33
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
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
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
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
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
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
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
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
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
154 static void ipi_flush_tlb_a15_erratum(void *arg)
155 {
156         dmb();
157 }
158
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
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
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
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
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
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
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
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
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 }