xref: /openbmc/qemu/include/hw/ppc/xive.h (revision 464e447a)
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 "hw/qdev-core.h"
144 #include "hw/sysbus.h"
145 #include "hw/ppc/xive_regs.h"
146 
147 /*
148  * XIVE Fabric (Interface between Source and Router)
149  */
150 
151 typedef struct XiveNotifier {
152     Object parent;
153 } XiveNotifier;
154 
155 #define TYPE_XIVE_NOTIFIER "xive-notifier"
156 #define XIVE_NOTIFIER(obj)                                     \
157     OBJECT_CHECK(XiveNotifier, (obj), TYPE_XIVE_NOTIFIER)
158 #define XIVE_NOTIFIER_CLASS(klass)                                     \
159     OBJECT_CLASS_CHECK(XiveNotifierClass, (klass), TYPE_XIVE_NOTIFIER)
160 #define XIVE_NOTIFIER_GET_CLASS(obj)                                   \
161     OBJECT_GET_CLASS(XiveNotifierClass, (obj), TYPE_XIVE_NOTIFIER)
162 
163 typedef struct XiveNotifierClass {
164     InterfaceClass parent;
165     void (*notify)(XiveNotifier *xn, uint32_t lisn);
166 } XiveNotifierClass;
167 
168 /*
169  * XIVE Interrupt Source
170  */
171 
172 #define TYPE_XIVE_SOURCE "xive-source"
173 #define XIVE_SOURCE(obj) OBJECT_CHECK(XiveSource, (obj), TYPE_XIVE_SOURCE)
174 
175 /*
176  * XIVE Interrupt Source characteristics, which define how the ESB are
177  * controlled.
178  */
179 #define XIVE_SRC_H_INT_ESB     0x1 /* ESB managed with hcall H_INT_ESB */
180 #define XIVE_SRC_STORE_EOI     0x2 /* Store EOI supported */
181 
182 typedef struct XiveSource {
183     DeviceState parent;
184 
185     /* IRQs */
186     uint32_t        nr_irqs;
187     qemu_irq        *qirqs;
188     unsigned long   *lsi_map;
189 
190     /* PQ bits and LSI assertion bit */
191     uint8_t         *status;
192 
193     /* ESB memory region */
194     uint64_t        esb_flags;
195     uint32_t        esb_shift;
196     MemoryRegion    esb_mmio;
197 
198     XiveNotifier    *xive;
199 } XiveSource;
200 
201 /*
202  * ESB MMIO setting. Can be one page, for both source triggering and
203  * source management, or two different pages. See below for magic
204  * values.
205  */
206 #define XIVE_ESB_4K          12 /* PSI HB only */
207 #define XIVE_ESB_4K_2PAGE    13
208 #define XIVE_ESB_64K         16
209 #define XIVE_ESB_64K_2PAGE   17
210 
211 static inline bool xive_source_esb_has_2page(XiveSource *xsrc)
212 {
213     return xsrc->esb_shift == XIVE_ESB_64K_2PAGE ||
214         xsrc->esb_shift == XIVE_ESB_4K_2PAGE;
215 }
216 
217 /* The trigger page is always the first/even page */
218 static inline hwaddr xive_source_esb_page(XiveSource *xsrc, uint32_t srcno)
219 {
220     assert(srcno < xsrc->nr_irqs);
221     return (1ull << xsrc->esb_shift) * srcno;
222 }
223 
224 /* In a two pages ESB MMIO setting, the odd page is for management */
225 static inline hwaddr xive_source_esb_mgmt(XiveSource *xsrc, int srcno)
226 {
227     hwaddr addr = xive_source_esb_page(xsrc, srcno);
228 
229     if (xive_source_esb_has_2page(xsrc)) {
230         addr += (1 << (xsrc->esb_shift - 1));
231     }
232 
233     return addr;
234 }
235 
236 /*
237  * Each interrupt source has a 2-bit state machine which can be
238  * controlled by MMIO. P indicates that an interrupt is pending (has
239  * been sent to a queue and is waiting for an EOI). Q indicates that
240  * the interrupt has been triggered while pending.
241  *
242  * This acts as a coalescing mechanism in order to guarantee that a
243  * given interrupt only occurs at most once in a queue.
244  *
245  * When doing an EOI, the Q bit will indicate if the interrupt
246  * needs to be re-triggered.
247  */
248 #define XIVE_STATUS_ASSERTED  0x4  /* Extra bit for LSI */
249 #define XIVE_ESB_VAL_P        0x2
250 #define XIVE_ESB_VAL_Q        0x1
251 
252 #define XIVE_ESB_RESET        0x0
253 #define XIVE_ESB_PENDING      XIVE_ESB_VAL_P
254 #define XIVE_ESB_QUEUED       (XIVE_ESB_VAL_P | XIVE_ESB_VAL_Q)
255 #define XIVE_ESB_OFF          XIVE_ESB_VAL_Q
256 
257 /*
258  * "magic" Event State Buffer (ESB) MMIO offsets.
259  *
260  * The following offsets into the ESB MMIO allow to read or manipulate
261  * the PQ bits. They must be used with an 8-byte load instruction.
262  * They all return the previous state of the interrupt (atomically).
263  *
264  * Additionally, some ESB pages support doing an EOI via a store and
265  * some ESBs support doing a trigger via a separate trigger page.
266  */
267 #define XIVE_ESB_STORE_EOI      0x400 /* Store */
268 #define XIVE_ESB_LOAD_EOI       0x000 /* Load */
269 #define XIVE_ESB_GET            0x800 /* Load */
270 #define XIVE_ESB_SET_PQ_00      0xc00 /* Load */
271 #define XIVE_ESB_SET_PQ_01      0xd00 /* Load */
272 #define XIVE_ESB_SET_PQ_10      0xe00 /* Load */
273 #define XIVE_ESB_SET_PQ_11      0xf00 /* Load */
274 
275 uint8_t xive_source_esb_get(XiveSource *xsrc, uint32_t srcno);
276 uint8_t xive_source_esb_set(XiveSource *xsrc, uint32_t srcno, uint8_t pq);
277 
278 void xive_source_pic_print_info(XiveSource *xsrc, uint32_t offset,
279                                 Monitor *mon);
280 
281 static inline qemu_irq xive_source_qirq(XiveSource *xsrc, uint32_t srcno)
282 {
283     assert(srcno < xsrc->nr_irqs);
284     return xsrc->qirqs[srcno];
285 }
286 
287 static inline bool xive_source_irq_is_lsi(XiveSource *xsrc, uint32_t srcno)
288 {
289     assert(srcno < xsrc->nr_irqs);
290     return test_bit(srcno, xsrc->lsi_map);
291 }
292 
293 static inline void xive_source_irq_set(XiveSource *xsrc, uint32_t srcno,
294                                        bool lsi)
295 {
296     assert(srcno < xsrc->nr_irqs);
297     if (lsi) {
298         bitmap_set(xsrc->lsi_map, srcno, 1);
299     }
300 }
301 
302 /*
303  * XIVE Router
304  */
305 
306 typedef struct XiveRouter {
307     SysBusDevice    parent;
308 } XiveRouter;
309 
310 #define TYPE_XIVE_ROUTER "xive-router"
311 #define XIVE_ROUTER(obj)                                \
312     OBJECT_CHECK(XiveRouter, (obj), TYPE_XIVE_ROUTER)
313 #define XIVE_ROUTER_CLASS(klass)                                        \
314     OBJECT_CLASS_CHECK(XiveRouterClass, (klass), TYPE_XIVE_ROUTER)
315 #define XIVE_ROUTER_GET_CLASS(obj)                              \
316     OBJECT_GET_CLASS(XiveRouterClass, (obj), TYPE_XIVE_ROUTER)
317 
318 typedef struct XiveRouterClass {
319     SysBusDeviceClass parent;
320 
321     /* XIVE table accessors */
322     int (*get_eas)(XiveRouter *xrtr, uint8_t eas_blk, uint32_t eas_idx,
323                    XiveEAS *eas);
324     int (*get_end)(XiveRouter *xrtr, uint8_t end_blk, uint32_t end_idx,
325                    XiveEND *end);
326     int (*write_end)(XiveRouter *xrtr, uint8_t end_blk, uint32_t end_idx,
327                      XiveEND *end, uint8_t word_number);
328     int (*get_nvt)(XiveRouter *xrtr, uint8_t nvt_blk, uint32_t nvt_idx,
329                    XiveNVT *nvt);
330     int (*write_nvt)(XiveRouter *xrtr, uint8_t nvt_blk, uint32_t nvt_idx,
331                      XiveNVT *nvt, uint8_t word_number);
332 } XiveRouterClass;
333 
334 void xive_eas_pic_print_info(XiveEAS *eas, uint32_t lisn, Monitor *mon);
335 
336 int xive_router_get_eas(XiveRouter *xrtr, uint8_t eas_blk, uint32_t eas_idx,
337                         XiveEAS *eas);
338 int xive_router_get_end(XiveRouter *xrtr, uint8_t end_blk, uint32_t end_idx,
339                         XiveEND *end);
340 int xive_router_write_end(XiveRouter *xrtr, uint8_t end_blk, uint32_t end_idx,
341                           XiveEND *end, uint8_t word_number);
342 int xive_router_get_nvt(XiveRouter *xrtr, uint8_t nvt_blk, uint32_t nvt_idx,
343                         XiveNVT *nvt);
344 int xive_router_write_nvt(XiveRouter *xrtr, uint8_t nvt_blk, uint32_t nvt_idx,
345                           XiveNVT *nvt, uint8_t word_number);
346 
347 
348 /*
349  * XIVE END ESBs
350  */
351 
352 #define TYPE_XIVE_END_SOURCE "xive-end-source"
353 #define XIVE_END_SOURCE(obj) \
354     OBJECT_CHECK(XiveENDSource, (obj), TYPE_XIVE_END_SOURCE)
355 
356 typedef struct XiveENDSource {
357     DeviceState parent;
358 
359     uint32_t        nr_ends;
360     uint8_t         block_id;
361 
362     /* ESB memory region */
363     uint32_t        esb_shift;
364     MemoryRegion    esb_mmio;
365 
366     XiveRouter      *xrtr;
367 } XiveENDSource;
368 
369 /*
370  * For legacy compatibility, the exceptions define up to 256 different
371  * priorities. P9 implements only 9 levels : 8 active levels [0 - 7]
372  * and the least favored level 0xFF.
373  */
374 #define XIVE_PRIORITY_MAX  7
375 
376 void xive_end_pic_print_info(XiveEND *end, uint32_t end_idx, Monitor *mon);
377 void xive_end_queue_pic_print_info(XiveEND *end, uint32_t width, Monitor *mon);
378 
379 /*
380  * XIVE Thread interrupt Management (TM) context
381  */
382 
383 #define TYPE_XIVE_TCTX "xive-tctx"
384 #define XIVE_TCTX(obj) OBJECT_CHECK(XiveTCTX, (obj), TYPE_XIVE_TCTX)
385 
386 /*
387  * XIVE Thread interrupt Management register rings :
388  *
389  *   QW-0  User       event-based exception state
390  *   QW-1  O/S        OS context for priority management, interrupt acks
391  *   QW-2  Pool       hypervisor pool context for virtual processors dispatched
392  *   QW-3  Physical   physical thread context and security context
393  */
394 #define XIVE_TM_RING_COUNT      4
395 #define XIVE_TM_RING_SIZE       0x10
396 
397 typedef struct XiveTCTX {
398     DeviceState parent_obj;
399 
400     CPUState    *cs;
401     qemu_irq    output;
402 
403     uint8_t     regs[XIVE_TM_RING_COUNT * XIVE_TM_RING_SIZE];
404 } XiveTCTX;
405 
406 /*
407  * XIVE Thread Interrupt Management Aera (TIMA)
408  *
409  * This region gives access to the registers of the thread interrupt
410  * management context. It is four page wide, each page providing a
411  * different view of the registers. The page with the lower offset is
412  * the most privileged and gives access to the entire context.
413  */
414 #define XIVE_TM_HW_PAGE         0x0
415 #define XIVE_TM_HV_PAGE         0x1
416 #define XIVE_TM_OS_PAGE         0x2
417 #define XIVE_TM_USER_PAGE       0x3
418 
419 extern const MemoryRegionOps xive_tm_ops;
420 
421 void xive_tctx_pic_print_info(XiveTCTX *tctx, Monitor *mon);
422 Object *xive_tctx_create(Object *cpu, XiveRouter *xrtr, Error **errp);
423 
424 static inline uint32_t xive_nvt_cam_line(uint8_t nvt_blk, uint32_t nvt_idx)
425 {
426     return (nvt_blk << 19) | nvt_idx;
427 }
428 
429 #endif /* PPC_XIVE_H */
430