xref: /openbmc/qemu/include/hw/ppc/xive.h (revision 83a71719)
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 Notifier (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     unsigned long   *lsi_map;
188 
189     /* PQ bits and LSI assertion bit */
190     uint8_t         *status;
191 
192     /* ESB memory region */
193     uint64_t        esb_flags;
194     uint32_t        esb_shift;
195     MemoryRegion    esb_mmio;
196 
197     XiveNotifier    *xive;
198 } XiveSource;
199 
200 /*
201  * ESB MMIO setting. Can be one page, for both source triggering and
202  * source management, or two different pages. See below for magic
203  * values.
204  */
205 #define XIVE_ESB_4K          12 /* PSI HB only */
206 #define XIVE_ESB_4K_2PAGE    13
207 #define XIVE_ESB_64K         16
208 #define XIVE_ESB_64K_2PAGE   17
209 
210 static inline bool xive_source_esb_has_2page(XiveSource *xsrc)
211 {
212     return xsrc->esb_shift == XIVE_ESB_64K_2PAGE ||
213         xsrc->esb_shift == XIVE_ESB_4K_2PAGE;
214 }
215 
216 /* The trigger page is always the first/even page */
217 static inline hwaddr xive_source_esb_page(XiveSource *xsrc, uint32_t srcno)
218 {
219     assert(srcno < xsrc->nr_irqs);
220     return (1ull << xsrc->esb_shift) * srcno;
221 }
222 
223 /* In a two pages ESB MMIO setting, the odd page is for management */
224 static inline hwaddr xive_source_esb_mgmt(XiveSource *xsrc, int srcno)
225 {
226     hwaddr addr = xive_source_esb_page(xsrc, srcno);
227 
228     if (xive_source_esb_has_2page(xsrc)) {
229         addr += (1 << (xsrc->esb_shift - 1));
230     }
231 
232     return addr;
233 }
234 
235 /*
236  * Each interrupt source has a 2-bit state machine which can be
237  * controlled by MMIO. P indicates that an interrupt is pending (has
238  * been sent to a queue and is waiting for an EOI). Q indicates that
239  * the interrupt has been triggered while pending.
240  *
241  * This acts as a coalescing mechanism in order to guarantee that a
242  * given interrupt only occurs at most once in a queue.
243  *
244  * When doing an EOI, the Q bit will indicate if the interrupt
245  * needs to be re-triggered.
246  */
247 #define XIVE_STATUS_ASSERTED  0x4  /* Extra bit for LSI */
248 #define XIVE_ESB_VAL_P        0x2
249 #define XIVE_ESB_VAL_Q        0x1
250 
251 #define XIVE_ESB_RESET        0x0
252 #define XIVE_ESB_PENDING      XIVE_ESB_VAL_P
253 #define XIVE_ESB_QUEUED       (XIVE_ESB_VAL_P | XIVE_ESB_VAL_Q)
254 #define XIVE_ESB_OFF          XIVE_ESB_VAL_Q
255 
256 /*
257  * "magic" Event State Buffer (ESB) MMIO offsets.
258  *
259  * The following offsets into the ESB MMIO allow to read or manipulate
260  * the PQ bits. They must be used with an 8-byte load instruction.
261  * They all return the previous state of the interrupt (atomically).
262  *
263  * Additionally, some ESB pages support doing an EOI via a store and
264  * some ESBs support doing a trigger via a separate trigger page.
265  */
266 #define XIVE_ESB_STORE_EOI      0x400 /* Store */
267 #define XIVE_ESB_LOAD_EOI       0x000 /* Load */
268 #define XIVE_ESB_GET            0x800 /* Load */
269 #define XIVE_ESB_SET_PQ_00      0xc00 /* Load */
270 #define XIVE_ESB_SET_PQ_01      0xd00 /* Load */
271 #define XIVE_ESB_SET_PQ_10      0xe00 /* Load */
272 #define XIVE_ESB_SET_PQ_11      0xf00 /* Load */
273 
274 uint8_t xive_source_esb_get(XiveSource *xsrc, uint32_t srcno);
275 uint8_t xive_source_esb_set(XiveSource *xsrc, uint32_t srcno, uint8_t pq);
276 
277 void xive_source_pic_print_info(XiveSource *xsrc, uint32_t offset,
278                                 Monitor *mon);
279 
280 static inline bool xive_source_irq_is_lsi(XiveSource *xsrc, uint32_t srcno)
281 {
282     assert(srcno < xsrc->nr_irqs);
283     return test_bit(srcno, xsrc->lsi_map);
284 }
285 
286 static inline void xive_source_irq_set(XiveSource *xsrc, uint32_t srcno,
287                                        bool lsi)
288 {
289     assert(srcno < xsrc->nr_irqs);
290     if (lsi) {
291         bitmap_set(xsrc->lsi_map, srcno, 1);
292     }
293 }
294 
295 void xive_source_set_irq(void *opaque, int srcno, int val);
296 
297 /*
298  * XIVE Thread interrupt Management (TM) context
299  */
300 
301 #define TYPE_XIVE_TCTX "xive-tctx"
302 #define XIVE_TCTX(obj) OBJECT_CHECK(XiveTCTX, (obj), TYPE_XIVE_TCTX)
303 
304 /*
305  * XIVE Thread interrupt Management register rings :
306  *
307  *   QW-0  User       event-based exception state
308  *   QW-1  O/S        OS context for priority management, interrupt acks
309  *   QW-2  Pool       hypervisor pool context for virtual processors dispatched
310  *   QW-3  Physical   physical thread context and security context
311  */
312 #define XIVE_TM_RING_COUNT      4
313 #define XIVE_TM_RING_SIZE       0x10
314 
315 typedef struct XiveTCTX {
316     DeviceState parent_obj;
317 
318     CPUState    *cs;
319     qemu_irq    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 void xive_eas_pic_print_info(XiveEAS *eas, uint32_t lisn, Monitor *mon);
358 
359 int xive_router_get_eas(XiveRouter *xrtr, uint8_t eas_blk, uint32_t eas_idx,
360                         XiveEAS *eas);
361 int xive_router_get_end(XiveRouter *xrtr, uint8_t end_blk, uint32_t end_idx,
362                         XiveEND *end);
363 int xive_router_write_end(XiveRouter *xrtr, uint8_t end_blk, uint32_t end_idx,
364                           XiveEND *end, uint8_t word_number);
365 int xive_router_get_nvt(XiveRouter *xrtr, uint8_t nvt_blk, uint32_t nvt_idx,
366                         XiveNVT *nvt);
367 int xive_router_write_nvt(XiveRouter *xrtr, uint8_t nvt_blk, uint32_t nvt_idx,
368                           XiveNVT *nvt, uint8_t word_number);
369 XiveTCTX *xive_router_get_tctx(XiveRouter *xrtr, CPUState *cs);
370 
371 /*
372  * XIVE END ESBs
373  */
374 
375 #define TYPE_XIVE_END_SOURCE "xive-end-source"
376 #define XIVE_END_SOURCE(obj) \
377     OBJECT_CHECK(XiveENDSource, (obj), TYPE_XIVE_END_SOURCE)
378 
379 typedef struct XiveENDSource {
380     DeviceState parent;
381 
382     uint32_t        nr_ends;
383     uint8_t         block_id;
384 
385     /* ESB memory region */
386     uint32_t        esb_shift;
387     MemoryRegion    esb_mmio;
388 
389     XiveRouter      *xrtr;
390 } XiveENDSource;
391 
392 /*
393  * For legacy compatibility, the exceptions define up to 256 different
394  * priorities. P9 implements only 9 levels : 8 active levels [0 - 7]
395  * and the least favored level 0xFF.
396  */
397 #define XIVE_PRIORITY_MAX  7
398 
399 void xive_end_pic_print_info(XiveEND *end, uint32_t end_idx, Monitor *mon);
400 void xive_end_queue_pic_print_info(XiveEND *end, uint32_t width, Monitor *mon);
401 
402 /*
403  * XIVE Thread Interrupt Management Aera (TIMA)
404  *
405  * This region gives access to the registers of the thread interrupt
406  * management context. It is four page wide, each page providing a
407  * different view of the registers. The page with the lower offset is
408  * the most privileged and gives access to the entire context.
409  */
410 #define XIVE_TM_HW_PAGE         0x0
411 #define XIVE_TM_HV_PAGE         0x1
412 #define XIVE_TM_OS_PAGE         0x2
413 #define XIVE_TM_USER_PAGE       0x3
414 
415 extern const MemoryRegionOps xive_tm_ops;
416 
417 void xive_tctx_pic_print_info(XiveTCTX *tctx, Monitor *mon);
418 Object *xive_tctx_create(Object *cpu, XiveRouter *xrtr, Error **errp);
419 
420 static inline uint32_t xive_nvt_cam_line(uint8_t nvt_blk, uint32_t nvt_idx)
421 {
422     return (nvt_blk << 19) | nvt_idx;
423 }
424 
425 #endif /* PPC_XIVE_H */
426