xref: /openbmc/qemu/hw/intc/xics_kvm.c (revision 3f53bc61)
1 /*
2  * QEMU PowerPC pSeries Logical Partition (aka sPAPR) hardware System Emulator
3  *
4  * PAPR Virtualized Interrupt System, aka ICS/ICP aka xics, in-kernel emulation
5  *
6  * Copyright (c) 2013 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 
28 #include "qemu/osdep.h"
29 #include "qapi/error.h"
30 #include "qemu-common.h"
31 #include "cpu.h"
32 #include "hw/hw.h"
33 #include "trace.h"
34 #include "sysemu/kvm.h"
35 #include "hw/ppc/spapr.h"
36 #include "hw/ppc/xics.h"
37 #include "kvm_ppc.h"
38 #include "qemu/config-file.h"
39 #include "qemu/error-report.h"
40 
41 #include <sys/ioctl.h>
42 
43 static int kernel_xics_fd = -1;
44 
45 /*
46  * ICP-KVM
47  */
48 static void icp_get_kvm_state(ICPState *icp)
49 {
50     uint64_t state;
51     struct kvm_one_reg reg = {
52         .id = KVM_REG_PPC_ICP_STATE,
53         .addr = (uintptr_t)&state,
54     };
55     int ret;
56 
57     /* ICP for this CPU thread is not in use, exiting */
58     if (!icp->cs) {
59         return;
60     }
61 
62     ret = kvm_vcpu_ioctl(icp->cs, KVM_GET_ONE_REG, &reg);
63     if (ret != 0) {
64         error_report("Unable to retrieve KVM interrupt controller state"
65                 " for CPU %ld: %s", kvm_arch_vcpu_id(icp->cs), strerror(errno));
66         exit(1);
67     }
68 
69     icp->xirr = state >> KVM_REG_PPC_ICP_XISR_SHIFT;
70     icp->mfrr = (state >> KVM_REG_PPC_ICP_MFRR_SHIFT)
71         & KVM_REG_PPC_ICP_MFRR_MASK;
72     icp->pending_priority = (state >> KVM_REG_PPC_ICP_PPRI_SHIFT)
73         & KVM_REG_PPC_ICP_PPRI_MASK;
74 }
75 
76 static int icp_set_kvm_state(ICPState *icp, int version_id)
77 {
78     uint64_t state;
79     struct kvm_one_reg reg = {
80         .id = KVM_REG_PPC_ICP_STATE,
81         .addr = (uintptr_t)&state,
82     };
83     int ret;
84 
85     /* ICP for this CPU thread is not in use, exiting */
86     if (!icp->cs) {
87         return 0;
88     }
89 
90     state = ((uint64_t)icp->xirr << KVM_REG_PPC_ICP_XISR_SHIFT)
91         | ((uint64_t)icp->mfrr << KVM_REG_PPC_ICP_MFRR_SHIFT)
92         | ((uint64_t)icp->pending_priority << KVM_REG_PPC_ICP_PPRI_SHIFT);
93 
94     ret = kvm_vcpu_ioctl(icp->cs, KVM_SET_ONE_REG, &reg);
95     if (ret != 0) {
96         error_report("Unable to restore KVM interrupt controller state (0x%"
97                 PRIx64 ") for CPU %ld: %s", state, kvm_arch_vcpu_id(icp->cs),
98                 strerror(errno));
99         return ret;
100     }
101 
102     return 0;
103 }
104 
105 static void icp_kvm_reset(void *dev)
106 {
107     ICPState *icp = ICP(dev);
108 
109     icp->xirr = 0;
110     icp->pending_priority = 0xff;
111     icp->mfrr = 0xff;
112 
113     /* Make all outputs as deasserted only if the CPU thread is in use */
114     if (icp->output) {
115         qemu_set_irq(icp->output, 0);
116     }
117 
118     icp_set_kvm_state(icp, 1);
119 }
120 
121 static void icp_kvm_cpu_setup(ICPState *icp, PowerPCCPU *cpu)
122 {
123     CPUState *cs = CPU(cpu);
124     int ret;
125 
126     if (kernel_xics_fd == -1) {
127         abort();
128     }
129 
130     /*
131      * If we are reusing a parked vCPU fd corresponding to the CPU
132      * which was hot-removed earlier we don't have to renable
133      * KVM_CAP_IRQ_XICS capability again.
134      */
135     if (icp->cap_irq_xics_enabled) {
136         return;
137     }
138 
139     ret = kvm_vcpu_enable_cap(cs, KVM_CAP_IRQ_XICS, 0, kernel_xics_fd,
140                               kvm_arch_vcpu_id(cs));
141     if (ret < 0) {
142         error_report("Unable to connect CPU%ld to kernel XICS: %s",
143                      kvm_arch_vcpu_id(cs), strerror(errno));
144         exit(1);
145     }
146     icp->cap_irq_xics_enabled = true;
147 }
148 
149 static void icp_kvm_realize(DeviceState *dev, Error **errp)
150 {
151     qemu_register_reset(icp_kvm_reset, dev);
152 }
153 
154 static void icp_kvm_class_init(ObjectClass *klass, void *data)
155 {
156     DeviceClass *dc = DEVICE_CLASS(klass);
157     ICPStateClass *icpc = ICP_CLASS(klass);
158 
159     dc->realize = icp_kvm_realize;
160     icpc->pre_save = icp_get_kvm_state;
161     icpc->post_load = icp_set_kvm_state;
162     icpc->cpu_setup = icp_kvm_cpu_setup;
163 }
164 
165 static const TypeInfo icp_kvm_info = {
166     .name = TYPE_KVM_ICP,
167     .parent = TYPE_ICP,
168     .instance_size = sizeof(ICPState),
169     .class_init = icp_kvm_class_init,
170     .class_size = sizeof(ICPStateClass),
171 };
172 
173 /*
174  * ICS-KVM
175  */
176 static void ics_get_kvm_state(ICSState *ics)
177 {
178     uint64_t state;
179     struct kvm_device_attr attr = {
180         .flags = 0,
181         .group = KVM_DEV_XICS_GRP_SOURCES,
182         .addr = (uint64_t)(uintptr_t)&state,
183     };
184     int i;
185 
186     for (i = 0; i < ics->nr_irqs; i++) {
187         ICSIRQState *irq = &ics->irqs[i];
188         int ret;
189 
190         attr.attr = i + ics->offset;
191 
192         ret = ioctl(kernel_xics_fd, KVM_GET_DEVICE_ATTR, &attr);
193         if (ret != 0) {
194             error_report("Unable to retrieve KVM interrupt controller state"
195                     " for IRQ %d: %s", i + ics->offset, strerror(errno));
196             exit(1);
197         }
198 
199         irq->server = state & KVM_XICS_DESTINATION_MASK;
200         irq->saved_priority = (state >> KVM_XICS_PRIORITY_SHIFT)
201             & KVM_XICS_PRIORITY_MASK;
202         /*
203          * To be consistent with the software emulation in xics.c, we
204          * split out the masked state + priority that we get from the
205          * kernel into 'current priority' (0xff if masked) and
206          * 'saved priority' (if masked, this is the priority the
207          * interrupt had before it was masked).  Masking and unmasking
208          * are done with the ibm,int-off and ibm,int-on RTAS calls.
209          */
210         if (state & KVM_XICS_MASKED) {
211             irq->priority = 0xff;
212         } else {
213             irq->priority = irq->saved_priority;
214         }
215 
216         if (state & KVM_XICS_PENDING) {
217             if (state & KVM_XICS_LEVEL_SENSITIVE) {
218                 irq->status |= XICS_STATUS_ASSERTED;
219             } else {
220                 /*
221                  * A pending edge-triggered interrupt (or MSI)
222                  * must have been rejected previously when we
223                  * first detected it and tried to deliver it,
224                  * so mark it as pending and previously rejected
225                  * for consistency with how xics.c works.
226                  */
227                 irq->status |= XICS_STATUS_MASKED_PENDING
228                     | XICS_STATUS_REJECTED;
229             }
230         }
231     }
232 }
233 
234 static int ics_set_kvm_state(ICSState *ics, int version_id)
235 {
236     uint64_t state;
237     struct kvm_device_attr attr = {
238         .flags = 0,
239         .group = KVM_DEV_XICS_GRP_SOURCES,
240         .addr = (uint64_t)(uintptr_t)&state,
241     };
242     int i;
243 
244     for (i = 0; i < ics->nr_irqs; i++) {
245         ICSIRQState *irq = &ics->irqs[i];
246         int ret;
247 
248         attr.attr = i + ics->offset;
249 
250         state = irq->server;
251         state |= (uint64_t)(irq->saved_priority & KVM_XICS_PRIORITY_MASK)
252             << KVM_XICS_PRIORITY_SHIFT;
253         if (irq->priority != irq->saved_priority) {
254             assert(irq->priority == 0xff);
255             state |= KVM_XICS_MASKED;
256         }
257 
258         if (ics->irqs[i].flags & XICS_FLAGS_IRQ_LSI) {
259             state |= KVM_XICS_LEVEL_SENSITIVE;
260             if (irq->status & XICS_STATUS_ASSERTED) {
261                 state |= KVM_XICS_PENDING;
262             }
263         } else {
264             if (irq->status & XICS_STATUS_MASKED_PENDING) {
265                 state |= KVM_XICS_PENDING;
266             }
267         }
268 
269         ret = ioctl(kernel_xics_fd, KVM_SET_DEVICE_ATTR, &attr);
270         if (ret != 0) {
271             error_report("Unable to restore KVM interrupt controller state"
272                     " for IRQs %d: %s", i + ics->offset, strerror(errno));
273             return ret;
274         }
275     }
276 
277     return 0;
278 }
279 
280 static void ics_kvm_set_irq(void *opaque, int srcno, int val)
281 {
282     ICSState *ics = opaque;
283     struct kvm_irq_level args;
284     int rc;
285 
286     args.irq = srcno + ics->offset;
287     if (ics->irqs[srcno].flags & XICS_FLAGS_IRQ_MSI) {
288         if (!val) {
289             return;
290         }
291         args.level = KVM_INTERRUPT_SET;
292     } else {
293         args.level = val ? KVM_INTERRUPT_SET_LEVEL : KVM_INTERRUPT_UNSET;
294     }
295     rc = kvm_vm_ioctl(kvm_state, KVM_IRQ_LINE, &args);
296     if (rc < 0) {
297         perror("kvm_irq_line");
298     }
299 }
300 
301 static void ics_kvm_reset(void *dev)
302 {
303     ICSState *ics = ICS_SIMPLE(dev);
304     int i;
305     uint8_t flags[ics->nr_irqs];
306 
307     for (i = 0; i < ics->nr_irqs; i++) {
308         flags[i] = ics->irqs[i].flags;
309     }
310 
311     memset(ics->irqs, 0, sizeof(ICSIRQState) * ics->nr_irqs);
312 
313     for (i = 0; i < ics->nr_irqs; i++) {
314         ics->irqs[i].priority = 0xff;
315         ics->irqs[i].saved_priority = 0xff;
316         ics->irqs[i].flags = flags[i];
317     }
318 
319     ics_set_kvm_state(ics, 1);
320 }
321 
322 static void ics_kvm_realize(DeviceState *dev, Error **errp)
323 {
324     ICSState *ics = ICS_SIMPLE(dev);
325 
326     if (!ics->nr_irqs) {
327         error_setg(errp, "Number of interrupts needs to be greater 0");
328         return;
329     }
330     ics->irqs = g_malloc0(ics->nr_irqs * sizeof(ICSIRQState));
331     ics->qirqs = qemu_allocate_irqs(ics_kvm_set_irq, ics, ics->nr_irqs);
332 
333     qemu_register_reset(ics_kvm_reset, dev);
334 }
335 
336 static void ics_kvm_class_init(ObjectClass *klass, void *data)
337 {
338     ICSStateClass *icsc = ICS_BASE_CLASS(klass);
339 
340     icsc->realize = ics_kvm_realize;
341     icsc->pre_save = ics_get_kvm_state;
342     icsc->post_load = ics_set_kvm_state;
343 }
344 
345 static const TypeInfo ics_kvm_info = {
346     .name = TYPE_ICS_KVM,
347     .parent = TYPE_ICS_SIMPLE,
348     .instance_size = sizeof(ICSState),
349     .class_init = ics_kvm_class_init,
350 };
351 
352 /*
353  * XICS-KVM
354  */
355 
356 static void rtas_dummy(PowerPCCPU *cpu, sPAPRMachineState *spapr,
357                        uint32_t token,
358                        uint32_t nargs, target_ulong args,
359                        uint32_t nret, target_ulong rets)
360 {
361     error_report("pseries: %s must never be called for in-kernel XICS",
362                  __func__);
363 }
364 
365 int xics_kvm_init(sPAPRMachineState *spapr, Error **errp)
366 {
367     int rc;
368     struct kvm_create_device xics_create_device = {
369         .type = KVM_DEV_TYPE_XICS,
370         .flags = 0,
371     };
372 
373     if (!kvm_enabled() || !kvm_check_extension(kvm_state, KVM_CAP_IRQ_XICS)) {
374         error_setg(errp,
375                    "KVM and IRQ_XICS capability must be present for in-kernel XICS");
376         goto fail;
377     }
378 
379     spapr_rtas_register(RTAS_IBM_SET_XIVE, "ibm,set-xive", rtas_dummy);
380     spapr_rtas_register(RTAS_IBM_GET_XIVE, "ibm,get-xive", rtas_dummy);
381     spapr_rtas_register(RTAS_IBM_INT_OFF, "ibm,int-off", rtas_dummy);
382     spapr_rtas_register(RTAS_IBM_INT_ON, "ibm,int-on", rtas_dummy);
383 
384     rc = kvmppc_define_rtas_kernel_token(RTAS_IBM_SET_XIVE, "ibm,set-xive");
385     if (rc < 0) {
386         error_setg(errp, "kvmppc_define_rtas_kernel_token: ibm,set-xive");
387         goto fail;
388     }
389 
390     rc = kvmppc_define_rtas_kernel_token(RTAS_IBM_GET_XIVE, "ibm,get-xive");
391     if (rc < 0) {
392         error_setg(errp, "kvmppc_define_rtas_kernel_token: ibm,get-xive");
393         goto fail;
394     }
395 
396     rc = kvmppc_define_rtas_kernel_token(RTAS_IBM_INT_ON, "ibm,int-on");
397     if (rc < 0) {
398         error_setg(errp, "kvmppc_define_rtas_kernel_token: ibm,int-on");
399         goto fail;
400     }
401 
402     rc = kvmppc_define_rtas_kernel_token(RTAS_IBM_INT_OFF, "ibm,int-off");
403     if (rc < 0) {
404         error_setg(errp, "kvmppc_define_rtas_kernel_token: ibm,int-off");
405         goto fail;
406     }
407 
408     /* Create the kernel ICP */
409     rc = kvm_vm_ioctl(kvm_state, KVM_CREATE_DEVICE, &xics_create_device);
410     if (rc < 0) {
411         error_setg_errno(errp, -rc, "Error on KVM_CREATE_DEVICE for XICS");
412         goto fail;
413     }
414 
415     kernel_xics_fd = xics_create_device.fd;
416 
417     kvm_kernel_irqchip = true;
418     kvm_msi_via_irqfd_allowed = true;
419     kvm_gsi_direct_mapping = true;
420 
421     return rc;
422 
423 fail:
424     kvmppc_define_rtas_kernel_token(0, "ibm,set-xive");
425     kvmppc_define_rtas_kernel_token(0, "ibm,get-xive");
426     kvmppc_define_rtas_kernel_token(0, "ibm,int-on");
427     kvmppc_define_rtas_kernel_token(0, "ibm,int-off");
428     return -1;
429 }
430 
431 static void xics_kvm_register_types(void)
432 {
433     type_register_static(&ics_kvm_info);
434     type_register_static(&icp_kvm_info);
435 }
436 
437 type_init(xics_kvm_register_types)
438