xref: /openbmc/qemu/include/hw/ppc/xive.h (revision f3635813)
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 
147 /*
148  * XIVE Notifier (Interface between Source and Router)
149  */
150 
151 typedef struct XiveNotifier XiveNotifier;
152 
153 #define TYPE_XIVE_NOTIFIER "xive-notifier"
154 #define XIVE_NOTIFIER(obj)                                     \
155     INTERFACE_CHECK(XiveNotifier, (obj), TYPE_XIVE_NOTIFIER)
156 #define XIVE_NOTIFIER_CLASS(klass)                                     \
157     OBJECT_CLASS_CHECK(XiveNotifierClass, (klass), TYPE_XIVE_NOTIFIER)
158 #define XIVE_NOTIFIER_GET_CLASS(obj)                                   \
159     OBJECT_GET_CLASS(XiveNotifierClass, (obj), TYPE_XIVE_NOTIFIER)
160 
161 typedef struct XiveNotifierClass {
162     InterfaceClass parent;
163     void (*notify)(XiveNotifier *xn, uint32_t lisn);
164 } XiveNotifierClass;
165 
166 /*
167  * XIVE Interrupt Source
168  */
169 
170 #define TYPE_XIVE_SOURCE "xive-source"
171 #define XIVE_SOURCE(obj) OBJECT_CHECK(XiveSource, (obj), TYPE_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 
180 typedef struct XiveSource {
181     DeviceState parent;
182 
183     /* IRQs */
184     uint32_t        nr_irqs;
185     unsigned long   *lsi_map;
186 
187     /* PQ bits and LSI assertion bit */
188     uint8_t         *status;
189 
190     /* ESB memory region */
191     uint64_t        esb_flags;
192     uint32_t        esb_shift;
193     MemoryRegion    esb_mmio;
194 
195     /* KVM support */
196     void            *esb_mmap;
197     MemoryRegion    esb_mmio_kvm;
198 
199     XiveNotifier    *xive;
200 } XiveSource;
201 
202 /*
203  * ESB MMIO setting. Can be one page, for both source triggering and
204  * source management, or two different pages. See below for magic
205  * values.
206  */
207 #define XIVE_ESB_4K          12 /* PSI HB only */
208 #define XIVE_ESB_4K_2PAGE    13
209 #define XIVE_ESB_64K         16
210 #define XIVE_ESB_64K_2PAGE   17
211 
212 static inline bool xive_source_esb_has_2page(XiveSource *xsrc)
213 {
214     return xsrc->esb_shift == XIVE_ESB_64K_2PAGE ||
215         xsrc->esb_shift == XIVE_ESB_4K_2PAGE;
216 }
217 
218 /* The trigger page is always the first/even page */
219 static inline hwaddr xive_source_esb_page(XiveSource *xsrc, uint32_t srcno)
220 {
221     assert(srcno < xsrc->nr_irqs);
222     return (1ull << xsrc->esb_shift) * srcno;
223 }
224 
225 /* In a two pages ESB MMIO setting, the odd page is for management */
226 static inline hwaddr xive_source_esb_mgmt(XiveSource *xsrc, int srcno)
227 {
228     hwaddr addr = xive_source_esb_page(xsrc, srcno);
229 
230     if (xive_source_esb_has_2page(xsrc)) {
231         addr += (1 << (xsrc->esb_shift - 1));
232     }
233 
234     return addr;
235 }
236 
237 /*
238  * Each interrupt source has a 2-bit state machine which can be
239  * controlled by MMIO. P indicates that an interrupt is pending (has
240  * been sent to a queue and is waiting for an EOI). Q indicates that
241  * the interrupt has been triggered while pending.
242  *
243  * This acts as a coalescing mechanism in order to guarantee that a
244  * given interrupt only occurs at most once in a queue.
245  *
246  * When doing an EOI, the Q bit will indicate if the interrupt
247  * needs to be re-triggered.
248  */
249 #define XIVE_STATUS_ASSERTED  0x4  /* Extra bit for LSI */
250 #define XIVE_ESB_VAL_P        0x2
251 #define XIVE_ESB_VAL_Q        0x1
252 
253 #define XIVE_ESB_RESET        0x0
254 #define XIVE_ESB_PENDING      XIVE_ESB_VAL_P
255 #define XIVE_ESB_QUEUED       (XIVE_ESB_VAL_P | XIVE_ESB_VAL_Q)
256 #define XIVE_ESB_OFF          XIVE_ESB_VAL_Q
257 
258 /*
259  * "magic" Event State Buffer (ESB) MMIO offsets.
260  *
261  * The following offsets into the ESB MMIO allow to read or manipulate
262  * the PQ bits. They must be used with an 8-byte load instruction.
263  * They all return the previous state of the interrupt (atomically).
264  *
265  * Additionally, some ESB pages support doing an EOI via a store and
266  * some ESBs support doing a trigger via a separate trigger page.
267  */
268 #define XIVE_ESB_STORE_EOI      0x400 /* Store */
269 #define XIVE_ESB_LOAD_EOI       0x000 /* Load */
270 #define XIVE_ESB_GET            0x800 /* Load */
271 #define XIVE_ESB_SET_PQ_00      0xc00 /* Load */
272 #define XIVE_ESB_SET_PQ_01      0xd00 /* Load */
273 #define XIVE_ESB_SET_PQ_10      0xe00 /* Load */
274 #define XIVE_ESB_SET_PQ_11      0xf00 /* Load */
275 
276 uint8_t xive_source_esb_get(XiveSource *xsrc, uint32_t srcno);
277 uint8_t xive_source_esb_set(XiveSource *xsrc, uint32_t srcno, uint8_t pq);
278 
279 void xive_source_pic_print_info(XiveSource *xsrc, uint32_t offset,
280                                 Monitor *mon);
281 
282 static inline bool xive_source_irq_is_lsi(XiveSource *xsrc, uint32_t srcno)
283 {
284     assert(srcno < xsrc->nr_irqs);
285     return test_bit(srcno, xsrc->lsi_map);
286 }
287 
288 static inline void xive_source_irq_set_lsi(XiveSource *xsrc, uint32_t srcno)
289 {
290     assert(srcno < xsrc->nr_irqs);
291     bitmap_set(xsrc->lsi_map, srcno, 1);
292 }
293 
294 void xive_source_set_irq(void *opaque, int srcno, int val);
295 
296 /*
297  * XIVE Thread interrupt Management (TM) context
298  */
299 
300 #define TYPE_XIVE_TCTX "xive-tctx"
301 #define XIVE_TCTX(obj) OBJECT_CHECK(XiveTCTX, (obj), TYPE_XIVE_TCTX)
302 
303 /*
304  * XIVE Thread interrupt Management register rings :
305  *
306  *   QW-0  User       event-based exception state
307  *   QW-1  O/S        OS context for priority management, interrupt acks
308  *   QW-2  Pool       hypervisor pool context for virtual processors dispatched
309  *   QW-3  Physical   physical thread context and security context
310  */
311 #define XIVE_TM_RING_COUNT      4
312 #define XIVE_TM_RING_SIZE       0x10
313 
314 typedef struct XiveTCTX {
315     DeviceState parent_obj;
316 
317     CPUState    *cs;
318     qemu_irq    hv_output;
319     qemu_irq    os_output;
320 
321     uint8_t     regs[XIVE_TM_RING_COUNT * XIVE_TM_RING_SIZE];
322 } XiveTCTX;
323 
324 /*
325  * XIVE Router
326  */
327 
328 typedef struct XiveRouter {
329     SysBusDevice    parent;
330 } XiveRouter;
331 
332 #define TYPE_XIVE_ROUTER "xive-router"
333 #define XIVE_ROUTER(obj)                                \
334     OBJECT_CHECK(XiveRouter, (obj), TYPE_XIVE_ROUTER)
335 #define XIVE_ROUTER_CLASS(klass)                                        \
336     OBJECT_CLASS_CHECK(XiveRouterClass, (klass), TYPE_XIVE_ROUTER)
337 #define XIVE_ROUTER_GET_CLASS(obj)                              \
338     OBJECT_GET_CLASS(XiveRouterClass, (obj), TYPE_XIVE_ROUTER)
339 
340 typedef struct XiveRouterClass {
341     SysBusDeviceClass parent;
342 
343     /* XIVE table accessors */
344     int (*get_eas)(XiveRouter *xrtr, uint8_t eas_blk, uint32_t eas_idx,
345                    XiveEAS *eas);
346     int (*get_end)(XiveRouter *xrtr, uint8_t end_blk, uint32_t end_idx,
347                    XiveEND *end);
348     int (*write_end)(XiveRouter *xrtr, uint8_t end_blk, uint32_t end_idx,
349                      XiveEND *end, uint8_t word_number);
350     int (*get_nvt)(XiveRouter *xrtr, uint8_t nvt_blk, uint32_t nvt_idx,
351                    XiveNVT *nvt);
352     int (*write_nvt)(XiveRouter *xrtr, uint8_t nvt_blk, uint32_t nvt_idx,
353                      XiveNVT *nvt, uint8_t word_number);
354     XiveTCTX *(*get_tctx)(XiveRouter *xrtr, CPUState *cs);
355 } XiveRouterClass;
356 
357 int xive_router_get_eas(XiveRouter *xrtr, uint8_t eas_blk, uint32_t eas_idx,
358                         XiveEAS *eas);
359 int xive_router_get_end(XiveRouter *xrtr, uint8_t end_blk, uint32_t end_idx,
360                         XiveEND *end);
361 int xive_router_write_end(XiveRouter *xrtr, uint8_t end_blk, uint32_t end_idx,
362                           XiveEND *end, uint8_t word_number);
363 int xive_router_get_nvt(XiveRouter *xrtr, uint8_t nvt_blk, uint32_t nvt_idx,
364                         XiveNVT *nvt);
365 int xive_router_write_nvt(XiveRouter *xrtr, uint8_t nvt_blk, uint32_t nvt_idx,
366                           XiveNVT *nvt, uint8_t word_number);
367 XiveTCTX *xive_router_get_tctx(XiveRouter *xrtr, CPUState *cs);
368 void xive_router_notify(XiveNotifier *xn, uint32_t lisn);
369 
370 /*
371  * XIVE END ESBs
372  */
373 
374 #define TYPE_XIVE_END_SOURCE "xive-end-source"
375 #define XIVE_END_SOURCE(obj) \
376     OBJECT_CHECK(XiveENDSource, (obj), TYPE_XIVE_END_SOURCE)
377 
378 typedef struct XiveENDSource {
379     DeviceState parent;
380 
381     uint32_t        nr_ends;
382     uint8_t         block_id;
383 
384     /* ESB memory region */
385     uint32_t        esb_shift;
386     MemoryRegion    esb_mmio;
387 
388     XiveRouter      *xrtr;
389 } XiveENDSource;
390 
391 /*
392  * For legacy compatibility, the exceptions define up to 256 different
393  * priorities. P9 implements only 9 levels : 8 active levels [0 - 7]
394  * and the least favored level 0xFF.
395  */
396 #define XIVE_PRIORITY_MAX  7
397 
398 /*
399  * XIVE Thread Interrupt Management Aera (TIMA)
400  *
401  * This region gives access to the registers of the thread interrupt
402  * management context. It is four page wide, each page providing a
403  * different view of the registers. The page with the lower offset is
404  * the most privileged and gives access to the entire context.
405  */
406 #define XIVE_TM_HW_PAGE         0x0
407 #define XIVE_TM_HV_PAGE         0x1
408 #define XIVE_TM_OS_PAGE         0x2
409 #define XIVE_TM_USER_PAGE       0x3
410 
411 extern const MemoryRegionOps xive_tm_ops;
412 void xive_tctx_tm_write(XiveTCTX *tctx, hwaddr offset, uint64_t value,
413                         unsigned size);
414 uint64_t xive_tctx_tm_read(XiveTCTX *tctx, hwaddr offset, unsigned size);
415 
416 void xive_tctx_pic_print_info(XiveTCTX *tctx, Monitor *mon);
417 Object *xive_tctx_create(Object *cpu, XiveRouter *xrtr, Error **errp);
418 void xive_tctx_reset(XiveTCTX *tctx);
419 void xive_tctx_destroy(XiveTCTX *tctx);
420 
421 static inline uint32_t xive_nvt_cam_line(uint8_t nvt_blk, uint32_t nvt_idx)
422 {
423     return (nvt_blk << 19) | nvt_idx;
424 }
425 
426 /*
427  * KVM XIVE device helpers
428  */
429 
430 int kvmppc_xive_source_reset_one(XiveSource *xsrc, int srcno, Error **errp);
431 void kvmppc_xive_source_set_irq(void *opaque, int srcno, int val);
432 void kvmppc_xive_cpu_connect(XiveTCTX *tctx, Error **errp);
433 void kvmppc_xive_cpu_synchronize_state(XiveTCTX *tctx, Error **errp);
434 void kvmppc_xive_cpu_get_state(XiveTCTX *tctx, Error **errp);
435 void kvmppc_xive_cpu_set_state(XiveTCTX *tctx, Error **errp);
436 
437 #endif /* PPC_XIVE_H */
438