xref: /openbmc/qemu/include/hw/ppc/xive.h (revision ffe98631)
1 /*
2  * QEMU PowerPC XIVE interrupt controller model
3  *
4  *
5  * The POWER9 processor comes with a new interrupt controller, called
6  * XIVE as "eXternal Interrupt Virtualization Engine".
7  *
8  * = Overall architecture
9  *
10  *
11  *              XIVE Interrupt Controller
12  *              +------------------------------------+      IPIs
13  *              | +---------+ +---------+ +--------+ |    +-------+
14  *              | |VC       | |CQ       | |PC      |----> | CORES |
15  *              | |     esb | |         | |        |----> |       |
16  *              | |     eas | |  Bridge | |   tctx |----> |       |
17  *              | |SC   end | |         | |    nvt | |    |       |
18  *  +------+    | +---------+ +----+----+ +--------+ |    +-+-+-+-+
19  *  | RAM  |    +------------------|-----------------+      | | |
20  *  |      |                       |                        | | |
21  *  |      |                       |                        | | |
22  *  |      |  +--------------------v------------------------v-v-v--+    other
23  *  |      <--+                     Power Bus                      +--> chips
24  *  |  esb |  +---------+-----------------------+------------------+
25  *  |  eas |            |                       |
26  *  |  end |         +--|------+                |
27  *  |  nvt |       +----+----+ |           +----+----+
28  *  +------+       |SC       | |           |SC       |
29  *                 |         | |           |         |
30  *                 | PQ-bits | |           | PQ-bits |
31  *                 | local   |-+           |  in VC  |
32  *                 +---------+             +---------+
33  *                    PCIe                 NX,NPU,CAPI
34  *
35  *                   SC: Source Controller (aka. IVSE)
36  *                   VC: Virtualization Controller (aka. IVRE)
37  *                   PC: Presentation Controller (aka. IVPE)
38  *                   CQ: Common Queue (Bridge)
39  *
40  *              PQ-bits: 2 bits source state machine (P:pending Q:queued)
41  *                  esb: Event State Buffer (Array of PQ bits in an IVSE)
42  *                  eas: Event Assignment Structure
43  *                  end: Event Notification Descriptor
44  *                  nvt: Notification Virtual Target
45  *                 tctx: Thread interrupt Context
46  *
47  *
48  * The XIVE IC is composed of three sub-engines :
49  *
50  * - Interrupt Virtualization Source Engine (IVSE), or Source
51  *   Controller (SC). These are found in PCI PHBs, in the PSI host
52  *   bridge controller, but also inside the main controller for the
53  *   core IPIs and other sub-chips (NX, CAP, NPU) of the
54  *   chip/processor. They are configured to feed the IVRE with events.
55  *
56  * - Interrupt Virtualization Routing Engine (IVRE) or Virtualization
57  *   Controller (VC). Its job is to match an event source with an
58  *   Event Notification Descriptor (END).
59  *
60  * - Interrupt Virtualization Presentation Engine (IVPE) or
61  *   Presentation Controller (PC). It maintains the interrupt context
62  *   state of each thread and handles the delivery of the external
63  *   exception to the thread.
64  *
65  * In XIVE 1.0, the sub-engines used to be referred as:
66  *
67  *   SC     Source Controller
68  *   VC     Virtualization Controller
69  *   PC     Presentation Controller
70  *   CQ     Common Queue (PowerBUS Bridge)
71  *
72  *
73  * = XIVE internal tables
74  *
75  * Each of the sub-engines uses a set of tables to redirect exceptions
76  * from event sources to CPU threads.
77  *
78  *                                           +-------+
79  *   User or OS                              |  EQ   |
80  *       or                          +------>|entries|
81  *   Hypervisor                      |       |  ..   |
82  *     Memory                        |       +-------+
83  *                                   |           ^
84  *                                   |           |
85  *              +-------------------------------------------------+
86  *                                   |           |
87  *   Hypervisor      +------+    +---+--+    +---+--+   +------+
88  *     Memory        | ESB  |    | EAT  |    | ENDT |   | NVTT |
89  *    (skiboot)      +----+-+    +----+-+    +----+-+   +------+
90  *                     ^  |        ^  |        ^  |       ^
91  *                     |  |        |  |        |  |       |
92  *              +-------------------------------------------------+
93  *                     |  |        |  |        |  |       |
94  *                     |  |        |  |        |  |       |
95  *                +----|--|--------|--|--------|--|-+   +-|-----+    +------+
96  *                |    |  |        |  |        |  | |   | | tctx|    |Thread|
97  *   IPI or   --> |    +  v        +  v        +  v |---| +  .. |----->     |
98  *  HW events --> |                                 |   |       |    |      |
99  *    IVSE        |             IVRE                |   | IVPE  |    +------+
100  *                +---------------------------------+   +-------+
101  *
102  *
103  *
104  * The IVSE have a 2-bits state machine, P for pending and Q for queued,
105  * for each source that allows events to be triggered. They are stored in
106  * an Event State Buffer (ESB) array and can be controlled by MMIOs.
107  *
108  * If the event is let through, the IVRE looks up in the Event Assignment
109  * Structure (EAS) table for an Event Notification Descriptor (END)
110  * configured for the source. Each Event Notification Descriptor defines
111  * a notification path to a CPU and an in-memory Event Queue, in which
112  * will be enqueued an EQ data for the OS to pull.
113  *
114  * The IVPE determines if a Notification Virtual Target (NVT) can
115  * handle the event by scanning the thread contexts of the VCPUs
116  * dispatched on the processor HW threads. It maintains the state of
117  * the thread interrupt context (TCTX) of each thread in a NVT table.
118  *
119  * = Acronyms
120  *
121  *          Description                     In XIVE 1.0, used to be referred as
122  *
123  *   EAS    Event Assignment Structure      IVE   Interrupt Virt. Entry
124  *   EAT    Event Assignment Table          IVT   Interrupt Virt. Table
125  *   ENDT   Event Notif. Descriptor Table   EQDT  Event Queue Desc. Table
126  *   EQ     Event Queue                     same
127  *   ESB    Event State Buffer              SBE   State Bit Entry
128  *   NVT    Notif. Virtual Target           VPD   Virtual Processor Desc.
129  *   NVTT   Notif. Virtual Target Table     VPDT  Virtual Processor Desc. Table
130  *   TCTX   Thread interrupt Context
131  *
132  *
133  * Copyright (c) 2017-2018, IBM Corporation.
134  *
135  * This code is licensed under the GPL version 2 or later. See the
136  * COPYING file in the top-level directory.
137  *
138  */
139 
140 #ifndef PPC_XIVE_H
141 #define PPC_XIVE_H
142 
143 #include "sysemu/kvm.h"
144 #include "hw/sysbus.h"
145 #include "hw/ppc/xive_regs.h"
146 #include "qom/object.h"
147 
148 /*
149  * XIVE Notifier (Interface between Source and Router)
150  */
151 
152 typedef struct XiveNotifier XiveNotifier;
153 
154 #define TYPE_XIVE_NOTIFIER "xive-notifier"
155 #define XIVE_NOTIFIER(obj)                                     \
156     INTERFACE_CHECK(XiveNotifier, (obj), TYPE_XIVE_NOTIFIER)
157 typedef struct XiveNotifierClass XiveNotifierClass;
158 DECLARE_CLASS_CHECKERS(XiveNotifierClass, XIVE_NOTIFIER,
159                        TYPE_XIVE_NOTIFIER)
160 
161 struct XiveNotifierClass {
162     InterfaceClass parent;
163     void (*notify)(XiveNotifier *xn, uint32_t lisn, bool pq_checked);
164 };
165 
166 /*
167  * XIVE Interrupt Source
168  */
169 
170 #define TYPE_XIVE_SOURCE "xive-source"
171 OBJECT_DECLARE_SIMPLE_TYPE(XiveSource, XIVE_SOURCE)
172 
173 /*
174  * XIVE Interrupt Source characteristics, which define how the ESB are
175  * controlled.
176  */
177 #define XIVE_SRC_H_INT_ESB     0x1 /* ESB managed with hcall H_INT_ESB */
178 #define XIVE_SRC_STORE_EOI     0x2 /* Store EOI supported */
179 #define XIVE_SRC_PQ_DISABLE    0x4 /* Disable check on the PQ state bits */
180 
181 struct XiveSource {
182     DeviceState parent;
183 
184     /* IRQs */
185     uint32_t        nr_irqs;
186     unsigned long   *lsi_map;
187 
188     /* PQ bits and LSI assertion bit */
189     uint8_t         *status;
190 
191     /* ESB memory region */
192     uint64_t        esb_flags;
193     uint32_t        esb_shift;
194     MemoryRegion    esb_mmio;
195     MemoryRegion    esb_mmio_emulated;
196 
197     /* KVM support */
198     void            *esb_mmap;
199     MemoryRegion    esb_mmio_kvm;
200 
201     XiveNotifier    *xive;
202 };
203 
204 /*
205  * ESB MMIO setting. Can be one page, for both source triggering and
206  * source management, or two different pages. See below for magic
207  * values.
208  */
209 #define XIVE_ESB_4K          12 /* PSI HB only */
210 #define XIVE_ESB_4K_2PAGE    13
211 #define XIVE_ESB_64K         16
212 #define XIVE_ESB_64K_2PAGE   17
213 
214 static inline bool xive_source_esb_has_2page(XiveSource *xsrc)
215 {
216     return xsrc->esb_shift == XIVE_ESB_64K_2PAGE ||
217         xsrc->esb_shift == XIVE_ESB_4K_2PAGE;
218 }
219 
220 static inline size_t xive_source_esb_len(XiveSource *xsrc)
221 {
222     return (1ull << xsrc->esb_shift) * xsrc->nr_irqs;
223 }
224 
225 /* The trigger page is always the first/even page */
226 static inline hwaddr xive_source_esb_page(XiveSource *xsrc, uint32_t srcno)
227 {
228     assert(srcno < xsrc->nr_irqs);
229     return (1ull << xsrc->esb_shift) * srcno;
230 }
231 
232 /* In a two pages ESB MMIO setting, the odd page is for management */
233 static inline hwaddr xive_source_esb_mgmt(XiveSource *xsrc, int srcno)
234 {
235     hwaddr addr = xive_source_esb_page(xsrc, srcno);
236 
237     if (xive_source_esb_has_2page(xsrc)) {
238         addr += (1 << (xsrc->esb_shift - 1));
239     }
240 
241     return addr;
242 }
243 
244 /*
245  * Each interrupt source has a 2-bit state machine which can be
246  * controlled by MMIO. P indicates that an interrupt is pending (has
247  * been sent to a queue and is waiting for an EOI). Q indicates that
248  * the interrupt has been triggered while pending.
249  *
250  * This acts as a coalescing mechanism in order to guarantee that a
251  * given interrupt only occurs at most once in a queue.
252  *
253  * When doing an EOI, the Q bit will indicate if the interrupt
254  * needs to be re-triggered.
255  */
256 #define XIVE_STATUS_ASSERTED  0x4  /* Extra bit for LSI */
257 #define XIVE_ESB_VAL_P        0x2
258 #define XIVE_ESB_VAL_Q        0x1
259 
260 #define XIVE_ESB_RESET        0x0
261 #define XIVE_ESB_PENDING      XIVE_ESB_VAL_P
262 #define XIVE_ESB_QUEUED       (XIVE_ESB_VAL_P | XIVE_ESB_VAL_Q)
263 #define XIVE_ESB_OFF          XIVE_ESB_VAL_Q
264 
265 bool xive_esb_trigger(uint8_t *pq);
266 bool xive_esb_eoi(uint8_t *pq);
267 uint8_t xive_esb_set(uint8_t *pq, uint8_t value);
268 
269 /*
270  * "magic" Event State Buffer (ESB) MMIO offsets.
271  *
272  * The following offsets into the ESB MMIO allow to read or manipulate
273  * the PQ bits. They must be used with an 8-byte load instruction.
274  * They all return the previous state of the interrupt (atomically).
275  *
276  * Additionally, some ESB pages support doing an EOI via a store and
277  * some ESBs support doing a trigger via a separate trigger page.
278  */
279 #define XIVE_ESB_STORE_EOI      0x400 /* Store */
280 #define XIVE_ESB_LOAD_EOI       0x000 /* Load */
281 #define XIVE_ESB_GET            0x800 /* Load */
282 #define XIVE_ESB_INJECT         0x800 /* Store */
283 #define XIVE_ESB_SET_PQ_00      0xc00 /* Load */
284 #define XIVE_ESB_SET_PQ_01      0xd00 /* Load */
285 #define XIVE_ESB_SET_PQ_10      0xe00 /* Load */
286 #define XIVE_ESB_SET_PQ_11      0xf00 /* Load */
287 
288 uint8_t xive_source_esb_get(XiveSource *xsrc, uint32_t srcno);
289 uint8_t xive_source_esb_set(XiveSource *xsrc, uint32_t srcno, uint8_t pq);
290 
291 /*
292  * Source status helpers
293  */
294 static inline void xive_source_set_status(XiveSource *xsrc, uint32_t srcno,
295                                           uint8_t status, bool enable)
296 {
297     if (enable) {
298         xsrc->status[srcno] |= status;
299     } else {
300         xsrc->status[srcno] &= ~status;
301     }
302 }
303 
304 static inline void xive_source_set_asserted(XiveSource *xsrc, uint32_t srcno,
305                                             bool enable)
306 {
307     xive_source_set_status(xsrc, srcno, XIVE_STATUS_ASSERTED, enable);
308 }
309 
310 static inline bool xive_source_is_asserted(XiveSource *xsrc, uint32_t srcno)
311 {
312     return xsrc->status[srcno] & XIVE_STATUS_ASSERTED;
313 }
314 
315 void xive_source_pic_print_info(XiveSource *xsrc, uint32_t offset,
316                                 Monitor *mon);
317 
318 static inline bool xive_source_irq_is_lsi(XiveSource *xsrc, uint32_t srcno)
319 {
320     assert(srcno < xsrc->nr_irqs);
321     return test_bit(srcno, xsrc->lsi_map);
322 }
323 
324 static inline void xive_source_irq_set_lsi(XiveSource *xsrc, uint32_t srcno)
325 {
326     assert(srcno < xsrc->nr_irqs);
327     bitmap_set(xsrc->lsi_map, srcno, 1);
328 }
329 
330 void xive_source_set_irq(void *opaque, int srcno, int val);
331 
332 /*
333  * XIVE Thread interrupt Management (TM) context
334  */
335 
336 #define TYPE_XIVE_TCTX "xive-tctx"
337 OBJECT_DECLARE_SIMPLE_TYPE(XiveTCTX, XIVE_TCTX)
338 
339 /*
340  * XIVE Thread interrupt Management register rings :
341  *
342  *   QW-0  User       event-based exception state
343  *   QW-1  O/S        OS context for priority management, interrupt acks
344  *   QW-2  Pool       hypervisor pool context for virtual processors dispatched
345  *   QW-3  Physical   physical thread context and security context
346  */
347 #define XIVE_TM_RING_COUNT      4
348 #define XIVE_TM_RING_SIZE       0x10
349 
350 typedef struct XivePresenter XivePresenter;
351 
352 struct XiveTCTX {
353     DeviceState parent_obj;
354 
355     CPUState    *cs;
356     qemu_irq    hv_output;
357     qemu_irq    os_output;
358 
359     uint8_t     regs[XIVE_TM_RING_COUNT * XIVE_TM_RING_SIZE];
360 
361     XivePresenter *xptr;
362 };
363 
364 static inline uint32_t xive_tctx_word2(uint8_t *ring)
365 {
366     return *((uint32_t *) &ring[TM_WORD2]);
367 }
368 
369 /*
370  * XIVE Router
371  */
372 typedef struct XiveFabric XiveFabric;
373 
374 struct XiveRouter {
375     SysBusDevice    parent;
376 
377     XiveFabric *xfb;
378 };
379 
380 #define TYPE_XIVE_ROUTER "xive-router"
381 OBJECT_DECLARE_TYPE(XiveRouter, XiveRouterClass,
382                     XIVE_ROUTER)
383 
384 struct XiveRouterClass {
385     SysBusDeviceClass parent;
386 
387     /* XIVE table accessors */
388     int (*get_eas)(XiveRouter *xrtr, uint8_t eas_blk, uint32_t eas_idx,
389                    XiveEAS *eas);
390     int (*get_pq)(XiveRouter *xrtr, uint8_t eas_blk, uint32_t eas_idx,
391                   uint8_t *pq);
392     int (*set_pq)(XiveRouter *xrtr, uint8_t eas_blk, uint32_t eas_idx,
393                   uint8_t *pq);
394     int (*get_end)(XiveRouter *xrtr, uint8_t end_blk, uint32_t end_idx,
395                    XiveEND *end);
396     int (*write_end)(XiveRouter *xrtr, uint8_t end_blk, uint32_t end_idx,
397                      XiveEND *end, uint8_t word_number);
398     int (*get_nvt)(XiveRouter *xrtr, uint8_t nvt_blk, uint32_t nvt_idx,
399                    XiveNVT *nvt);
400     int (*write_nvt)(XiveRouter *xrtr, uint8_t nvt_blk, uint32_t nvt_idx,
401                      XiveNVT *nvt, uint8_t word_number);
402     uint8_t (*get_block_id)(XiveRouter *xrtr);
403 };
404 
405 int xive_router_get_eas(XiveRouter *xrtr, uint8_t eas_blk, uint32_t eas_idx,
406                         XiveEAS *eas);
407 int xive_router_get_end(XiveRouter *xrtr, uint8_t end_blk, uint32_t end_idx,
408                         XiveEND *end);
409 int xive_router_write_end(XiveRouter *xrtr, uint8_t end_blk, uint32_t end_idx,
410                           XiveEND *end, uint8_t word_number);
411 int xive_router_get_nvt(XiveRouter *xrtr, uint8_t nvt_blk, uint32_t nvt_idx,
412                         XiveNVT *nvt);
413 int xive_router_write_nvt(XiveRouter *xrtr, uint8_t nvt_blk, uint32_t nvt_idx,
414                           XiveNVT *nvt, uint8_t word_number);
415 void xive_router_notify(XiveNotifier *xn, uint32_t lisn, bool pq_checked);
416 
417 /*
418  * XIVE Presenter
419  */
420 
421 typedef struct XiveTCTXMatch {
422     XiveTCTX *tctx;
423     uint8_t ring;
424 } XiveTCTXMatch;
425 
426 #define TYPE_XIVE_PRESENTER "xive-presenter"
427 #define XIVE_PRESENTER(obj)                                     \
428     INTERFACE_CHECK(XivePresenter, (obj), TYPE_XIVE_PRESENTER)
429 typedef struct XivePresenterClass XivePresenterClass;
430 DECLARE_CLASS_CHECKERS(XivePresenterClass, XIVE_PRESENTER,
431                        TYPE_XIVE_PRESENTER)
432 
433 struct XivePresenterClass {
434     InterfaceClass parent;
435     int (*match_nvt)(XivePresenter *xptr, uint8_t format,
436                      uint8_t nvt_blk, uint32_t nvt_idx,
437                      bool cam_ignore, uint8_t priority,
438                      uint32_t logic_serv, XiveTCTXMatch *match);
439     bool (*in_kernel)(const XivePresenter *xptr);
440 };
441 
442 int xive_presenter_tctx_match(XivePresenter *xptr, XiveTCTX *tctx,
443                               uint8_t format,
444                               uint8_t nvt_blk, uint32_t nvt_idx,
445                               bool cam_ignore, uint32_t logic_serv);
446 bool xive_presenter_notify(XiveFabric *xfb, uint8_t format,
447                            uint8_t nvt_blk, uint32_t nvt_idx,
448                            bool cam_ignore, uint8_t priority,
449                            uint32_t logic_serv);
450 
451 /*
452  * XIVE Fabric (Interface between Interrupt Controller and Machine)
453  */
454 
455 #define TYPE_XIVE_FABRIC "xive-fabric"
456 #define XIVE_FABRIC(obj)                                     \
457     INTERFACE_CHECK(XiveFabric, (obj), TYPE_XIVE_FABRIC)
458 typedef struct XiveFabricClass XiveFabricClass;
459 DECLARE_CLASS_CHECKERS(XiveFabricClass, XIVE_FABRIC,
460                        TYPE_XIVE_FABRIC)
461 
462 struct XiveFabricClass {
463     InterfaceClass parent;
464     int (*match_nvt)(XiveFabric *xfb, uint8_t format,
465                      uint8_t nvt_blk, uint32_t nvt_idx,
466                      bool cam_ignore, uint8_t priority,
467                      uint32_t logic_serv, XiveTCTXMatch *match);
468 };
469 
470 /*
471  * XIVE END ESBs
472  */
473 
474 #define TYPE_XIVE_END_SOURCE "xive-end-source"
475 OBJECT_DECLARE_SIMPLE_TYPE(XiveENDSource, XIVE_END_SOURCE)
476 
477 struct XiveENDSource {
478     DeviceState parent;
479 
480     uint32_t        nr_ends;
481 
482     /* ESB memory region */
483     uint32_t        esb_shift;
484     MemoryRegion    esb_mmio;
485 
486     XiveRouter      *xrtr;
487 };
488 
489 /*
490  * For legacy compatibility, the exceptions define up to 256 different
491  * priorities. P9 implements only 9 levels : 8 active levels [0 - 7]
492  * and the least favored level 0xFF.
493  */
494 #define XIVE_PRIORITY_MAX  7
495 
496 /*
497  * Convert a priority number to an Interrupt Pending Buffer (IPB)
498  * register, which indicates a pending interrupt at the priority
499  * corresponding to the bit number
500  */
501 static inline uint8_t xive_priority_to_ipb(uint8_t priority)
502 {
503     return priority > XIVE_PRIORITY_MAX ?
504         0 : 1 << (XIVE_PRIORITY_MAX - priority);
505 }
506 
507 /*
508  * XIVE Thread Interrupt Management Aera (TIMA)
509  *
510  * This region gives access to the registers of the thread interrupt
511  * management context. It is four page wide, each page providing a
512  * different view of the registers. The page with the lower offset is
513  * the most privileged and gives access to the entire context.
514  */
515 #define XIVE_TM_HW_PAGE         0x0
516 #define XIVE_TM_HV_PAGE         0x1
517 #define XIVE_TM_OS_PAGE         0x2
518 #define XIVE_TM_USER_PAGE       0x3
519 
520 void xive_tctx_tm_write(XivePresenter *xptr, XiveTCTX *tctx, hwaddr offset,
521                         uint64_t value, unsigned size);
522 uint64_t xive_tctx_tm_read(XivePresenter *xptr, XiveTCTX *tctx, hwaddr offset,
523                            unsigned size);
524 
525 void xive_tctx_pic_print_info(XiveTCTX *tctx, Monitor *mon);
526 Object *xive_tctx_create(Object *cpu, XivePresenter *xptr, Error **errp);
527 void xive_tctx_reset(XiveTCTX *tctx);
528 void xive_tctx_destroy(XiveTCTX *tctx);
529 void xive_tctx_ipb_update(XiveTCTX *tctx, uint8_t ring, uint8_t ipb);
530 void xive_tctx_reset_os_signal(XiveTCTX *tctx);
531 
532 /*
533  * KVM XIVE device helpers
534  */
535 
536 int kvmppc_xive_source_reset_one(XiveSource *xsrc, int srcno, Error **errp);
537 void kvmppc_xive_source_set_irq(void *opaque, int srcno, int val);
538 int kvmppc_xive_cpu_connect(XiveTCTX *tctx, Error **errp);
539 int kvmppc_xive_cpu_synchronize_state(XiveTCTX *tctx, Error **errp);
540 int kvmppc_xive_cpu_get_state(XiveTCTX *tctx, Error **errp);
541 int kvmppc_xive_cpu_set_state(XiveTCTX *tctx, Error **errp);
542 
543 #endif /* PPC_XIVE_H */
544