xref: /openbmc/qemu/hw/misc/allwinner-cpucfg.c (revision a6caeee8)
1 /*
2  * Allwinner CPU Configuration Module emulation
3  *
4  * Copyright (C) 2019 Niek Linnenbank <nieklinnenbank@gmail.com>
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 as published by
8  * the Free Software Foundation, either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include "qemu/osdep.h"
21 #include "qemu/units.h"
22 #include "hw/sysbus.h"
23 #include "migration/vmstate.h"
24 #include "qemu/log.h"
25 #include "qemu/module.h"
26 #include "qemu/error-report.h"
27 #include "qemu/timer.h"
28 #include "hw/core/cpu.h"
29 #include "target/arm/arm-powerctl.h"
30 #include "target/arm/cpu.h"
31 #include "hw/misc/allwinner-cpucfg.h"
32 #include "trace.h"
33 
34 /* CPUCFG register offsets */
35 enum {
36     REG_CPUS_RST_CTRL       = 0x0000, /* CPUs Reset Control */
37     REG_CPU0_RST_CTRL       = 0x0040, /* CPU#0 Reset Control */
38     REG_CPU0_CTRL           = 0x0044, /* CPU#0 Control */
39     REG_CPU0_STATUS         = 0x0048, /* CPU#0 Status */
40     REG_CPU1_RST_CTRL       = 0x0080, /* CPU#1 Reset Control */
41     REG_CPU1_CTRL           = 0x0084, /* CPU#1 Control */
42     REG_CPU1_STATUS         = 0x0088, /* CPU#1 Status */
43     REG_CPU2_RST_CTRL       = 0x00C0, /* CPU#2 Reset Control */
44     REG_CPU2_CTRL           = 0x00C4, /* CPU#2 Control */
45     REG_CPU2_STATUS         = 0x00C8, /* CPU#2 Status */
46     REG_CPU3_RST_CTRL       = 0x0100, /* CPU#3 Reset Control */
47     REG_CPU3_CTRL           = 0x0104, /* CPU#3 Control */
48     REG_CPU3_STATUS         = 0x0108, /* CPU#3 Status */
49     REG_CPU_SYS_RST         = 0x0140, /* CPU System Reset */
50     REG_CLK_GATING          = 0x0144, /* CPU Clock Gating */
51     REG_GEN_CTRL            = 0x0184, /* General Control */
52     REG_SUPER_STANDBY       = 0x01A0, /* Super Standby Flag */
53     REG_ENTRY_ADDR          = 0x01A4, /* Reset Entry Address */
54     REG_DBG_EXTERN          = 0x01E4, /* Debug External */
55     REG_CNT64_CTRL          = 0x0280, /* 64-bit Counter Control */
56     REG_CNT64_LOW           = 0x0284, /* 64-bit Counter Low */
57     REG_CNT64_HIGH          = 0x0288, /* 64-bit Counter High */
58 };
59 
60 /* CPUCFG register flags */
61 enum {
62     CPUX_RESET_RELEASED     = ((1 << 1) | (1 << 0)),
63     CPUX_STATUS_SMP         = (1 << 0),
64     CPU_SYS_RESET_RELEASED  = (1 << 0),
65     CLK_GATING_ENABLE       = ((1 << 8) | 0xF),
66 };
67 
68 /* CPUCFG register reset values */
69 enum {
70     REG_CLK_GATING_RST      = 0x0000010F,
71     REG_GEN_CTRL_RST        = 0x00000020,
72     REG_SUPER_STANDBY_RST   = 0x0,
73     REG_CNT64_CTRL_RST      = 0x0,
74 };
75 
76 /* CPUCFG constants */
77 enum {
78     CPU_EXCEPTION_LEVEL_ON_RESET = 3, /* EL3 */
79 };
80 
81 static void allwinner_cpucfg_cpu_reset(AwCpuCfgState *s, uint8_t cpu_id)
82 {
83     int ret;
84 
85     trace_allwinner_cpucfg_cpu_reset(cpu_id, s->entry_addr);
86 
87     ARMCPU *target_cpu = ARM_CPU(arm_get_cpu_by_id(cpu_id));
88     if (!target_cpu) {
89         /*
90          * Called with a bogus value for cpu_id. Guest error will
91          * already have been logged, we can simply return here.
92          */
93         return;
94     }
95     bool target_aa64 = arm_feature(&target_cpu->env, ARM_FEATURE_AARCH64);
96 
97     ret = arm_set_cpu_on(cpu_id, s->entry_addr, 0,
98                          CPU_EXCEPTION_LEVEL_ON_RESET, target_aa64);
99     if (ret != QEMU_ARM_POWERCTL_RET_SUCCESS) {
100         error_report("%s: failed to bring up CPU %d: err %d",
101                      __func__, cpu_id, ret);
102         return;
103     }
104 }
105 
106 static uint64_t allwinner_cpucfg_read(void *opaque, hwaddr offset,
107                                       unsigned size)
108 {
109     const AwCpuCfgState *s = AW_CPUCFG(opaque);
110     uint64_t val = 0;
111 
112     switch (offset) {
113     case REG_CPUS_RST_CTRL:     /* CPUs Reset Control */
114     case REG_CPU_SYS_RST:       /* CPU System Reset */
115         val = CPU_SYS_RESET_RELEASED;
116         break;
117     case REG_CPU0_RST_CTRL:     /* CPU#0 Reset Control */
118     case REG_CPU1_RST_CTRL:     /* CPU#1 Reset Control */
119     case REG_CPU2_RST_CTRL:     /* CPU#2 Reset Control */
120     case REG_CPU3_RST_CTRL:     /* CPU#3 Reset Control */
121         val = CPUX_RESET_RELEASED;
122         break;
123     case REG_CPU0_CTRL:         /* CPU#0 Control */
124     case REG_CPU1_CTRL:         /* CPU#1 Control */
125     case REG_CPU2_CTRL:         /* CPU#2 Control */
126     case REG_CPU3_CTRL:         /* CPU#3 Control */
127         val = 0;
128         break;
129     case REG_CPU0_STATUS:       /* CPU#0 Status */
130     case REG_CPU1_STATUS:       /* CPU#1 Status */
131     case REG_CPU2_STATUS:       /* CPU#2 Status */
132     case REG_CPU3_STATUS:       /* CPU#3 Status */
133         val = CPUX_STATUS_SMP;
134         break;
135     case REG_CLK_GATING:        /* CPU Clock Gating */
136         val = CLK_GATING_ENABLE;
137         break;
138     case REG_GEN_CTRL:          /* General Control */
139         val = s->gen_ctrl;
140         break;
141     case REG_SUPER_STANDBY:     /* Super Standby Flag */
142         val = s->super_standby;
143         break;
144     case REG_ENTRY_ADDR:        /* Reset Entry Address */
145         val = s->entry_addr;
146         break;
147     case REG_DBG_EXTERN:        /* Debug External */
148     case REG_CNT64_CTRL:        /* 64-bit Counter Control */
149     case REG_CNT64_LOW:         /* 64-bit Counter Low */
150     case REG_CNT64_HIGH:        /* 64-bit Counter High */
151         qemu_log_mask(LOG_UNIMP, "%s: unimplemented register at 0x%04x\n",
152                       __func__, (uint32_t)offset);
153         break;
154     default:
155         qemu_log_mask(LOG_GUEST_ERROR, "%s: out-of-bounds offset 0x%04x\n",
156                       __func__, (uint32_t)offset);
157         break;
158     }
159 
160     trace_allwinner_cpucfg_read(offset, val, size);
161 
162     return val;
163 }
164 
165 static void allwinner_cpucfg_write(void *opaque, hwaddr offset,
166                                    uint64_t val, unsigned size)
167 {
168     AwCpuCfgState *s = AW_CPUCFG(opaque);
169 
170     trace_allwinner_cpucfg_write(offset, val, size);
171 
172     switch (offset) {
173     case REG_CPUS_RST_CTRL:     /* CPUs Reset Control */
174     case REG_CPU_SYS_RST:       /* CPU System Reset */
175         break;
176     case REG_CPU0_RST_CTRL:     /* CPU#0 Reset Control */
177     case REG_CPU1_RST_CTRL:     /* CPU#1 Reset Control */
178     case REG_CPU2_RST_CTRL:     /* CPU#2 Reset Control */
179     case REG_CPU3_RST_CTRL:     /* CPU#3 Reset Control */
180         if (val) {
181             allwinner_cpucfg_cpu_reset(s, (offset - REG_CPU0_RST_CTRL) >> 6);
182         }
183         break;
184     case REG_CPU0_CTRL:         /* CPU#0 Control */
185     case REG_CPU1_CTRL:         /* CPU#1 Control */
186     case REG_CPU2_CTRL:         /* CPU#2 Control */
187     case REG_CPU3_CTRL:         /* CPU#3 Control */
188     case REG_CPU0_STATUS:       /* CPU#0 Status */
189     case REG_CPU1_STATUS:       /* CPU#1 Status */
190     case REG_CPU2_STATUS:       /* CPU#2 Status */
191     case REG_CPU3_STATUS:       /* CPU#3 Status */
192     case REG_CLK_GATING:        /* CPU Clock Gating */
193         break;
194     case REG_GEN_CTRL:          /* General Control */
195         s->gen_ctrl = val;
196         break;
197     case REG_SUPER_STANDBY:     /* Super Standby Flag */
198         s->super_standby = val;
199         break;
200     case REG_ENTRY_ADDR:        /* Reset Entry Address */
201         s->entry_addr = val;
202         break;
203     case REG_DBG_EXTERN:        /* Debug External */
204     case REG_CNT64_CTRL:        /* 64-bit Counter Control */
205     case REG_CNT64_LOW:         /* 64-bit Counter Low */
206     case REG_CNT64_HIGH:        /* 64-bit Counter High */
207         qemu_log_mask(LOG_UNIMP, "%s: unimplemented register at 0x%04x\n",
208                       __func__, (uint32_t)offset);
209         break;
210     default:
211         qemu_log_mask(LOG_GUEST_ERROR, "%s: out-of-bounds offset 0x%04x\n",
212                       __func__, (uint32_t)offset);
213         break;
214     }
215 }
216 
217 static const MemoryRegionOps allwinner_cpucfg_ops = {
218     .read = allwinner_cpucfg_read,
219     .write = allwinner_cpucfg_write,
220     .endianness = DEVICE_NATIVE_ENDIAN,
221     .valid = {
222         .min_access_size = 4,
223         .max_access_size = 4,
224     },
225     .impl.min_access_size = 4,
226 };
227 
228 static void allwinner_cpucfg_reset(DeviceState *dev)
229 {
230     AwCpuCfgState *s = AW_CPUCFG(dev);
231 
232     /* Set default values for registers */
233     s->gen_ctrl = REG_GEN_CTRL_RST;
234     s->super_standby = REG_SUPER_STANDBY_RST;
235     s->entry_addr = 0;
236 }
237 
238 static void allwinner_cpucfg_init(Object *obj)
239 {
240     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
241     AwCpuCfgState *s = AW_CPUCFG(obj);
242 
243     /* Memory mapping */
244     memory_region_init_io(&s->iomem, OBJECT(s), &allwinner_cpucfg_ops, s,
245                           TYPE_AW_CPUCFG, 1 * KiB);
246     sysbus_init_mmio(sbd, &s->iomem);
247 }
248 
249 static const VMStateDescription allwinner_cpucfg_vmstate = {
250     .name = "allwinner-cpucfg",
251     .version_id = 1,
252     .minimum_version_id = 1,
253     .fields = (VMStateField[]) {
254         VMSTATE_UINT32(gen_ctrl, AwCpuCfgState),
255         VMSTATE_UINT32(super_standby, AwCpuCfgState),
256         VMSTATE_UINT32(entry_addr, AwCpuCfgState),
257         VMSTATE_END_OF_LIST()
258     }
259 };
260 
261 static void allwinner_cpucfg_class_init(ObjectClass *klass, void *data)
262 {
263     DeviceClass *dc = DEVICE_CLASS(klass);
264 
265     dc->reset = allwinner_cpucfg_reset;
266     dc->vmsd = &allwinner_cpucfg_vmstate;
267 }
268 
269 static const TypeInfo allwinner_cpucfg_info = {
270     .name          = TYPE_AW_CPUCFG,
271     .parent        = TYPE_SYS_BUS_DEVICE,
272     .instance_init = allwinner_cpucfg_init,
273     .instance_size = sizeof(AwCpuCfgState),
274     .class_init    = allwinner_cpucfg_class_init,
275 };
276 
277 static void allwinner_cpucfg_register(void)
278 {
279     type_register_static(&allwinner_cpucfg_info);
280 }
281 
282 type_init(allwinner_cpucfg_register)
283