xref: /openbmc/qemu/hw/ppc/spapr_rtas.c (revision a42e9c41)
1 /*
2  * QEMU PowerPC pSeries Logical Partition (aka sPAPR) hardware System Emulator
3  *
4  * Hypercall based emulated RTAS
5  *
6  * Copyright (c) 2010-2011 David Gibson, IBM Corporation.
7  *
8  * Permission is hereby granted, free of charge, to any person obtaining a copy
9  * of this software and associated documentation files (the "Software"), to deal
10  * in the Software without restriction, including without limitation the rights
11  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12  * copies of the Software, and to permit persons to whom the Software is
13  * furnished to do so, subject to the following conditions:
14  *
15  * The above copyright notice and this permission notice shall be included in
16  * all copies or substantial portions of the Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
21  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24  * THE SOFTWARE.
25  *
26  */
27 #include "cpu.h"
28 #include "sysemu/sysemu.h"
29 #include "sysemu/char.h"
30 #include "hw/qdev.h"
31 #include "sysemu/device_tree.h"
32 
33 #include "hw/ppc/spapr.h"
34 #include "hw/ppc/spapr_vio.h"
35 
36 #include <libfdt.h>
37 
38 #define TOKEN_BASE      0x2000
39 #define TOKEN_MAX       0x100
40 
41 static void rtas_display_character(PowerPCCPU *cpu, sPAPREnvironment *spapr,
42                                    uint32_t token, uint32_t nargs,
43                                    target_ulong args,
44                                    uint32_t nret, target_ulong rets)
45 {
46     uint8_t c = rtas_ld(args, 0);
47     VIOsPAPRDevice *sdev = vty_lookup(spapr, 0);
48 
49     if (!sdev) {
50         rtas_st(rets, 0, -1);
51     } else {
52         vty_putchars(sdev, &c, sizeof(c));
53         rtas_st(rets, 0, 0);
54     }
55 }
56 
57 static void rtas_get_time_of_day(PowerPCCPU *cpu, sPAPREnvironment *spapr,
58                                  uint32_t token, uint32_t nargs,
59                                  target_ulong args,
60                                  uint32_t nret, target_ulong rets)
61 {
62     struct tm tm;
63 
64     if (nret != 8) {
65         rtas_st(rets, 0, -3);
66         return;
67     }
68 
69     qemu_get_timedate(&tm, spapr->rtc_offset);
70 
71     rtas_st(rets, 0, 0); /* Success */
72     rtas_st(rets, 1, tm.tm_year + 1900);
73     rtas_st(rets, 2, tm.tm_mon + 1);
74     rtas_st(rets, 3, tm.tm_mday);
75     rtas_st(rets, 4, tm.tm_hour);
76     rtas_st(rets, 5, tm.tm_min);
77     rtas_st(rets, 6, tm.tm_sec);
78     rtas_st(rets, 7, 0); /* we don't do nanoseconds */
79 }
80 
81 static void rtas_set_time_of_day(PowerPCCPU *cpu, sPAPREnvironment *spapr,
82                                  uint32_t token, uint32_t nargs,
83                                  target_ulong args,
84                                  uint32_t nret, target_ulong rets)
85 {
86     struct tm tm;
87 
88     tm.tm_year = rtas_ld(args, 0) - 1900;
89     tm.tm_mon = rtas_ld(args, 1) - 1;
90     tm.tm_mday = rtas_ld(args, 2);
91     tm.tm_hour = rtas_ld(args, 3);
92     tm.tm_min = rtas_ld(args, 4);
93     tm.tm_sec = rtas_ld(args, 5);
94 
95     /* Just generate a monitor event for the change */
96     rtc_change_mon_event(&tm);
97     spapr->rtc_offset = qemu_timedate_diff(&tm);
98 
99     rtas_st(rets, 0, 0); /* Success */
100 }
101 
102 static void rtas_power_off(PowerPCCPU *cpu, sPAPREnvironment *spapr,
103                            uint32_t token, uint32_t nargs, target_ulong args,
104                            uint32_t nret, target_ulong rets)
105 {
106     if (nargs != 2 || nret != 1) {
107         rtas_st(rets, 0, -3);
108         return;
109     }
110     qemu_system_shutdown_request();
111     rtas_st(rets, 0, 0);
112 }
113 
114 static void rtas_system_reboot(PowerPCCPU *cpu, sPAPREnvironment *spapr,
115                                uint32_t token, uint32_t nargs,
116                                target_ulong args,
117                                uint32_t nret, target_ulong rets)
118 {
119     if (nargs != 0 || nret != 1) {
120         rtas_st(rets, 0, -3);
121         return;
122     }
123     qemu_system_reset_request();
124     rtas_st(rets, 0, 0);
125 }
126 
127 static void rtas_query_cpu_stopped_state(PowerPCCPU *cpu_,
128                                          sPAPREnvironment *spapr,
129                                          uint32_t token, uint32_t nargs,
130                                          target_ulong args,
131                                          uint32_t nret, target_ulong rets)
132 {
133     target_ulong id;
134     CPUState *cpu;
135 
136     if (nargs != 1 || nret != 2) {
137         rtas_st(rets, 0, -3);
138         return;
139     }
140 
141     id = rtas_ld(args, 0);
142     cpu = qemu_get_cpu(id);
143     if (cpu != NULL) {
144         if (cpu->halted) {
145             rtas_st(rets, 1, 0);
146         } else {
147             rtas_st(rets, 1, 2);
148         }
149 
150         rtas_st(rets, 0, 0);
151         return;
152     }
153 
154     /* Didn't find a matching cpu */
155     rtas_st(rets, 0, -3);
156 }
157 
158 static void rtas_start_cpu(PowerPCCPU *cpu_, sPAPREnvironment *spapr,
159                            uint32_t token, uint32_t nargs,
160                            target_ulong args,
161                            uint32_t nret, target_ulong rets)
162 {
163     target_ulong id, start, r3;
164     CPUState *cs;
165 
166     if (nargs != 3 || nret != 1) {
167         rtas_st(rets, 0, -3);
168         return;
169     }
170 
171     id = rtas_ld(args, 0);
172     start = rtas_ld(args, 1);
173     r3 = rtas_ld(args, 2);
174 
175     cs = qemu_get_cpu(id);
176     if (cs != NULL) {
177         PowerPCCPU *cpu = POWERPC_CPU(cs);
178         CPUPPCState *env = &cpu->env;
179 
180         if (!cs->halted) {
181             rtas_st(rets, 0, -1);
182             return;
183         }
184 
185         /* This will make sure qemu state is up to date with kvm, and
186          * mark it dirty so our changes get flushed back before the
187          * new cpu enters */
188         kvm_cpu_synchronize_state(cs);
189 
190         env->msr = (1ULL << MSR_SF) | (1ULL << MSR_ME);
191         env->nip = start;
192         env->gpr[3] = r3;
193         cs->halted = 0;
194 
195         qemu_cpu_kick(cs);
196 
197         rtas_st(rets, 0, 0);
198         return;
199     }
200 
201     /* Didn't find a matching cpu */
202     rtas_st(rets, 0, -3);
203 }
204 
205 static void rtas_stop_self(PowerPCCPU *cpu, sPAPREnvironment *spapr,
206                            uint32_t token, uint32_t nargs,
207                            target_ulong args,
208                            uint32_t nret, target_ulong rets)
209 {
210     CPUState *cs = CPU(cpu);
211     CPUPPCState *env = &cpu->env;
212 
213     cs->halted = 1;
214     cpu_exit(cs);
215     /*
216      * While stopping a CPU, the guest calls H_CPPR which
217      * effectively disables interrupts on XICS level.
218      * However decrementer interrupts in TCG can still
219      * wake the CPU up so here we disable interrupts in MSR
220      * as well.
221      * As rtas_start_cpu() resets the whole MSR anyway, there is
222      * no need to bother with specific bits, we just clear it.
223      */
224     env->msr = 0;
225 }
226 
227 static struct rtas_call {
228     const char *name;
229     spapr_rtas_fn fn;
230 } rtas_table[TOKEN_MAX];
231 
232 struct rtas_call *rtas_next = rtas_table;
233 
234 target_ulong spapr_rtas_call(PowerPCCPU *cpu, sPAPREnvironment *spapr,
235                              uint32_t token, uint32_t nargs, target_ulong args,
236                              uint32_t nret, target_ulong rets)
237 {
238     if ((token >= TOKEN_BASE)
239         && ((token - TOKEN_BASE) < TOKEN_MAX)) {
240         struct rtas_call *call = rtas_table + (token - TOKEN_BASE);
241 
242         if (call->fn) {
243             call->fn(cpu, spapr, token, nargs, args, nret, rets);
244             return H_SUCCESS;
245         }
246     }
247 
248     /* HACK: Some Linux early debug code uses RTAS display-character,
249      * but assumes the token value is 0xa (which it is on some real
250      * machines) without looking it up in the device tree.  This
251      * special case makes this work */
252     if (token == 0xa) {
253         rtas_display_character(cpu, spapr, 0xa, nargs, args, nret, rets);
254         return H_SUCCESS;
255     }
256 
257     hcall_dprintf("Unknown RTAS token 0x%x\n", token);
258     rtas_st(rets, 0, -3);
259     return H_PARAMETER;
260 }
261 
262 int spapr_rtas_register(const char *name, spapr_rtas_fn fn)
263 {
264     int i;
265 
266     for (i = 0; i < (rtas_next - rtas_table); i++) {
267         if (strcmp(name, rtas_table[i].name) == 0) {
268             fprintf(stderr, "RTAS call \"%s\" registered twice\n", name);
269             exit(1);
270         }
271     }
272 
273     assert(rtas_next < (rtas_table + TOKEN_MAX));
274 
275     rtas_next->name = name;
276     rtas_next->fn = fn;
277 
278     return (rtas_next++ - rtas_table) + TOKEN_BASE;
279 }
280 
281 int spapr_rtas_device_tree_setup(void *fdt, hwaddr rtas_addr,
282                                  hwaddr rtas_size)
283 {
284     int ret;
285     int i;
286 
287     ret = fdt_add_mem_rsv(fdt, rtas_addr, rtas_size);
288     if (ret < 0) {
289         fprintf(stderr, "Couldn't add RTAS reserve entry: %s\n",
290                 fdt_strerror(ret));
291         return ret;
292     }
293 
294     ret = qemu_devtree_setprop_cell(fdt, "/rtas", "linux,rtas-base",
295                                     rtas_addr);
296     if (ret < 0) {
297         fprintf(stderr, "Couldn't add linux,rtas-base property: %s\n",
298                 fdt_strerror(ret));
299         return ret;
300     }
301 
302     ret = qemu_devtree_setprop_cell(fdt, "/rtas", "linux,rtas-entry",
303                                     rtas_addr);
304     if (ret < 0) {
305         fprintf(stderr, "Couldn't add linux,rtas-entry property: %s\n",
306                 fdt_strerror(ret));
307         return ret;
308     }
309 
310     ret = qemu_devtree_setprop_cell(fdt, "/rtas", "rtas-size",
311                                     rtas_size);
312     if (ret < 0) {
313         fprintf(stderr, "Couldn't add rtas-size property: %s\n",
314                 fdt_strerror(ret));
315         return ret;
316     }
317 
318     for (i = 0; i < TOKEN_MAX; i++) {
319         struct rtas_call *call = &rtas_table[i];
320 
321         if (!call->name) {
322             continue;
323         }
324 
325         ret = qemu_devtree_setprop_cell(fdt, "/rtas", call->name,
326                                         i + TOKEN_BASE);
327         if (ret < 0) {
328             fprintf(stderr, "Couldn't add rtas token for %s: %s\n",
329                     call->name, fdt_strerror(ret));
330             return ret;
331         }
332 
333     }
334     return 0;
335 }
336 
337 static void core_rtas_register_types(void)
338 {
339     spapr_rtas_register("display-character", rtas_display_character);
340     spapr_rtas_register("get-time-of-day", rtas_get_time_of_day);
341     spapr_rtas_register("set-time-of-day", rtas_set_time_of_day);
342     spapr_rtas_register("power-off", rtas_power_off);
343     spapr_rtas_register("system-reboot", rtas_system_reboot);
344     spapr_rtas_register("query-cpu-stopped-state",
345                         rtas_query_cpu_stopped_state);
346     spapr_rtas_register("start-cpu", rtas_start_cpu);
347     spapr_rtas_register("stop-self", rtas_stop_self);
348 }
349 
350 type_init(core_rtas_register_types)
351