xref: /openbmc/qemu/hw/cxl/cxl-component-utils.c (revision 259ebed4)
1 /*
2  * CXL Utility library for components
3  *
4  * Copyright(C) 2020 Intel Corporation.
5  *
6  * This work is licensed under the terms of the GNU GPL, version 2. See the
7  * COPYING file in the top-level directory.
8  */
9 
10 #include "qemu/osdep.h"
11 #include "qemu/log.h"
12 #include "qapi/error.h"
13 #include "hw/pci/pci.h"
14 #include "hw/cxl/cxl.h"
15 
16 /* CXL r3.0 Section 8.2.4.19.1 CXL HDM Decoder Capability Register */
17 int cxl_decoder_count_enc(int count)
18 {
19     switch (count) {
20     case 1: return 0x0;
21     case 2: return 0x1;
22     case 4: return 0x2;
23     case 6: return 0x3;
24     case 8: return 0x4;
25     case 10: return 0x5;
26     /* Switches and Host Bridges may have more than 10 decoders */
27     case 12: return 0x6;
28     case 14: return 0x7;
29     case 16: return 0x8;
30     case 20: return 0x9;
31     case 24: return 0xa;
32     case 28: return 0xb;
33     case 32: return 0xc;
34     }
35     return 0;
36 }
37 
38 int cxl_decoder_count_dec(int enc_cnt)
39 {
40     switch (enc_cnt) {
41     case 0x0: return 1;
42     case 0x1: return 2;
43     case 0x2: return 4;
44     case 0x3: return 6;
45     case 0x4: return 8;
46     case 0x5: return 10;
47     /* Switches and Host Bridges may have more than 10 decoders */
48     case 0x6: return 12;
49     case 0x7: return 14;
50     case 0x8: return 16;
51     case 0x9: return 20;
52     case 0xa: return 24;
53     case 0xb: return 28;
54     case 0xc: return 32;
55     }
56     return 0;
57 }
58 
59 hwaddr cxl_decode_ig(int ig)
60 {
61     return 1ULL << (ig + 8);
62 }
63 
64 static uint64_t cxl_cache_mem_read_reg(void *opaque, hwaddr offset,
65                                        unsigned size)
66 {
67     CXLComponentState *cxl_cstate = opaque;
68     ComponentRegisters *cregs = &cxl_cstate->crb;
69 
70     if (size == 8) {
71         qemu_log_mask(LOG_UNIMP,
72                       "CXL 8 byte cache mem registers not implemented\n");
73         return 0;
74     }
75 
76     if (cregs->special_ops && cregs->special_ops->read) {
77         return cregs->special_ops->read(cxl_cstate, offset, size);
78     } else {
79         return cregs->cache_mem_registers[offset / sizeof(*cregs->cache_mem_registers)];
80     }
81 }
82 
83 static void dumb_hdm_handler(CXLComponentState *cxl_cstate, hwaddr offset,
84                              uint32_t value)
85 {
86     ComponentRegisters *cregs = &cxl_cstate->crb;
87     uint32_t *cache_mem = cregs->cache_mem_registers;
88     bool should_commit = false;
89     bool should_uncommit = false;
90 
91     switch (offset) {
92     case A_CXL_HDM_DECODER0_CTRL:
93     case A_CXL_HDM_DECODER1_CTRL:
94     case A_CXL_HDM_DECODER2_CTRL:
95     case A_CXL_HDM_DECODER3_CTRL:
96         should_commit = FIELD_EX32(value, CXL_HDM_DECODER0_CTRL, COMMIT);
97         should_uncommit = !should_commit;
98         break;
99     default:
100         break;
101     }
102 
103     if (should_commit) {
104         value = FIELD_DP32(value, CXL_HDM_DECODER0_CTRL, ERR, 0);
105         value = FIELD_DP32(value, CXL_HDM_DECODER0_CTRL, COMMITTED, 1);
106     } else if (should_uncommit) {
107         value = FIELD_DP32(value, CXL_HDM_DECODER0_CTRL, ERR, 0);
108         value = FIELD_DP32(value, CXL_HDM_DECODER0_CTRL, COMMITTED, 0);
109     }
110     stl_le_p((uint8_t *)cache_mem + offset, value);
111 }
112 
113 static void cxl_cache_mem_write_reg(void *opaque, hwaddr offset, uint64_t value,
114                                     unsigned size)
115 {
116     CXLComponentState *cxl_cstate = opaque;
117     ComponentRegisters *cregs = &cxl_cstate->crb;
118     uint32_t mask;
119 
120     if (size == 8) {
121         qemu_log_mask(LOG_UNIMP,
122                       "CXL 8 byte cache mem registers not implemented\n");
123         return;
124     }
125     mask = cregs->cache_mem_regs_write_mask[offset / sizeof(*cregs->cache_mem_regs_write_mask)];
126     value &= mask;
127     /* RO bits should remain constant. Done by reading existing value */
128     value |= ~mask & cregs->cache_mem_registers[offset / sizeof(*cregs->cache_mem_registers)];
129     if (cregs->special_ops && cregs->special_ops->write) {
130         cregs->special_ops->write(cxl_cstate, offset, value, size);
131         return;
132     }
133 
134     if (offset >= A_CXL_HDM_DECODER_CAPABILITY &&
135         offset <= A_CXL_HDM_DECODER3_TARGET_LIST_HI) {
136         dumb_hdm_handler(cxl_cstate, offset, value);
137     } else {
138         cregs->cache_mem_registers[offset / sizeof(*cregs->cache_mem_registers)] = value;
139     }
140 }
141 
142 /*
143  * 8.2.3
144  *   The access restrictions specified in Section 8.2.2 also apply to CXL 2.0
145  *   Component Registers.
146  *
147  * 8.2.2
148  *   • A 32 bit register shall be accessed as a 4 Bytes quantity. Partial
149  *   reads are not permitted.
150  *   • A 64 bit register shall be accessed as a 8 Bytes quantity. Partial
151  *   reads are not permitted.
152  *
153  * As of the spec defined today, only 4 byte registers exist.
154  */
155 static const MemoryRegionOps cache_mem_ops = {
156     .read = cxl_cache_mem_read_reg,
157     .write = cxl_cache_mem_write_reg,
158     .endianness = DEVICE_LITTLE_ENDIAN,
159     .valid = {
160         .min_access_size = 4,
161         .max_access_size = 8,
162         .unaligned = false,
163     },
164     .impl = {
165         .min_access_size = 4,
166         .max_access_size = 8,
167     },
168 };
169 
170 void cxl_component_register_block_init(Object *obj,
171                                        CXLComponentState *cxl_cstate,
172                                        const char *type)
173 {
174     ComponentRegisters *cregs = &cxl_cstate->crb;
175 
176     memory_region_init(&cregs->component_registers, obj, type,
177                        CXL2_COMPONENT_BLOCK_SIZE);
178 
179     /* io registers controls link which we don't care about in QEMU */
180     memory_region_init_io(&cregs->io, obj, NULL, cregs, ".io",
181                           CXL2_COMPONENT_IO_REGION_SIZE);
182     memory_region_init_io(&cregs->cache_mem, obj, &cache_mem_ops, cregs,
183                           ".cache_mem", CXL2_COMPONENT_CM_REGION_SIZE);
184 
185     memory_region_add_subregion(&cregs->component_registers, 0, &cregs->io);
186     memory_region_add_subregion(&cregs->component_registers,
187                                 CXL2_COMPONENT_IO_REGION_SIZE,
188                                 &cregs->cache_mem);
189 }
190 
191 static void ras_init_common(uint32_t *reg_state, uint32_t *write_msk)
192 {
193     /*
194      * Error status is RW1C but given bits are not yet set, it can
195      * be handled as RO.
196      */
197     stl_le_p(reg_state + R_CXL_RAS_UNC_ERR_STATUS, 0);
198     stl_le_p(write_msk + R_CXL_RAS_UNC_ERR_STATUS, 0x1cfff);
199     /* Bits 12-13 and 17-31 reserved in CXL 2.0 */
200     stl_le_p(reg_state + R_CXL_RAS_UNC_ERR_MASK, 0x1cfff);
201     stl_le_p(write_msk + R_CXL_RAS_UNC_ERR_MASK, 0x1cfff);
202     stl_le_p(reg_state + R_CXL_RAS_UNC_ERR_SEVERITY, 0x1cfff);
203     stl_le_p(write_msk + R_CXL_RAS_UNC_ERR_SEVERITY, 0x1cfff);
204     stl_le_p(reg_state + R_CXL_RAS_COR_ERR_STATUS, 0);
205     stl_le_p(write_msk + R_CXL_RAS_COR_ERR_STATUS, 0x7f);
206     stl_le_p(reg_state + R_CXL_RAS_COR_ERR_MASK, 0x7f);
207     stl_le_p(write_msk + R_CXL_RAS_COR_ERR_MASK, 0x7f);
208     /* CXL switches and devices must set */
209     stl_le_p(reg_state + R_CXL_RAS_ERR_CAP_CTRL, 0x200);
210 }
211 
212 static void hdm_init_common(uint32_t *reg_state, uint32_t *write_msk,
213                             enum reg_type type)
214 {
215     int decoder_count = CXL_HDM_DECODER_COUNT;
216     int hdm_inc = R_CXL_HDM_DECODER1_BASE_LO - R_CXL_HDM_DECODER0_BASE_LO;
217     int i;
218 
219     ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_CAPABILITY, DECODER_COUNT,
220                      cxl_decoder_count_enc(decoder_count));
221     ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_CAPABILITY, TARGET_COUNT, 1);
222     ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_CAPABILITY, INTERLEAVE_256B, 1);
223     ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_CAPABILITY, INTERLEAVE_4K, 1);
224     ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_CAPABILITY, POISON_ON_ERR_CAP, 0);
225     ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_GLOBAL_CONTROL,
226                      HDM_DECODER_ENABLE, 0);
227     write_msk[R_CXL_HDM_DECODER_GLOBAL_CONTROL] = 0x3;
228     for (i = 0; i < decoder_count; i++) {
229         write_msk[R_CXL_HDM_DECODER0_BASE_LO + i * hdm_inc] = 0xf0000000;
230         write_msk[R_CXL_HDM_DECODER0_BASE_HI + i * hdm_inc] = 0xffffffff;
231         write_msk[R_CXL_HDM_DECODER0_SIZE_LO + i * hdm_inc] = 0xf0000000;
232         write_msk[R_CXL_HDM_DECODER0_SIZE_HI + i * hdm_inc] = 0xffffffff;
233         write_msk[R_CXL_HDM_DECODER0_CTRL + i * hdm_inc] = 0x13ff;
234         if (type == CXL2_DEVICE ||
235             type == CXL2_TYPE3_DEVICE ||
236             type == CXL2_LOGICAL_DEVICE) {
237             write_msk[R_CXL_HDM_DECODER0_TARGET_LIST_LO + i * hdm_inc] =
238                 0xf0000000;
239         } else {
240             write_msk[R_CXL_HDM_DECODER0_TARGET_LIST_LO + i * hdm_inc] =
241                 0xffffffff;
242         }
243         write_msk[R_CXL_HDM_DECODER0_TARGET_LIST_HI + i * hdm_inc] = 0xffffffff;
244     }
245 }
246 
247 void cxl_component_register_init_common(uint32_t *reg_state, uint32_t *write_msk,
248                                         enum reg_type type)
249 {
250     int caps = 0;
251 
252     /*
253      * In CXL 2.0 the capabilities required for each CXL component are such that,
254      * with the ordering chosen here, a single number can be used to define
255      * which capabilities should be provided.
256      */
257     switch (type) {
258     case CXL2_DOWNSTREAM_PORT:
259     case CXL2_DEVICE:
260         /* RAS, Link */
261         caps = 2;
262         break;
263     case CXL2_UPSTREAM_PORT:
264     case CXL2_TYPE3_DEVICE:
265     case CXL2_LOGICAL_DEVICE:
266         /* + HDM */
267         caps = 3;
268         break;
269     case CXL2_ROOT_PORT:
270         /* + Extended Security, + Snoop */
271         caps = 5;
272         break;
273     default:
274         abort();
275     }
276 
277     memset(reg_state, 0, CXL2_COMPONENT_CM_REGION_SIZE);
278 
279     /* CXL Capability Header Register */
280     ARRAY_FIELD_DP32(reg_state, CXL_CAPABILITY_HEADER, ID, 1);
281     ARRAY_FIELD_DP32(reg_state, CXL_CAPABILITY_HEADER, VERSION, 1);
282     ARRAY_FIELD_DP32(reg_state, CXL_CAPABILITY_HEADER, CACHE_MEM_VERSION, 1);
283     ARRAY_FIELD_DP32(reg_state, CXL_CAPABILITY_HEADER, ARRAY_SIZE, caps);
284 
285 #define init_cap_reg(reg, id, version)                                        \
286     QEMU_BUILD_BUG_ON(CXL_##reg##_REGISTERS_OFFSET == 0);                     \
287     do {                                                                      \
288         int which = R_CXL_##reg##_CAPABILITY_HEADER;                          \
289         reg_state[which] = FIELD_DP32(reg_state[which],                       \
290                                       CXL_##reg##_CAPABILITY_HEADER, ID, id); \
291         reg_state[which] =                                                    \
292             FIELD_DP32(reg_state[which], CXL_##reg##_CAPABILITY_HEADER,       \
293                        VERSION, version);                                     \
294         reg_state[which] =                                                    \
295             FIELD_DP32(reg_state[which], CXL_##reg##_CAPABILITY_HEADER, PTR,  \
296                        CXL_##reg##_REGISTERS_OFFSET);                         \
297     } while (0)
298 
299     init_cap_reg(RAS, 2, 2);
300     ras_init_common(reg_state, write_msk);
301 
302     init_cap_reg(LINK, 4, 2);
303 
304     if (caps < 3) {
305         return;
306     }
307 
308     init_cap_reg(HDM, 5, 1);
309     hdm_init_common(reg_state, write_msk, type);
310 
311     if (caps < 5) {
312         return;
313     }
314 
315     init_cap_reg(EXTSEC, 6, 1);
316     init_cap_reg(SNOOP, 8, 1);
317 
318 #undef init_cap_reg
319 }
320 
321 /*
322  * Helper to creates a DVSEC header for a CXL entity. The caller is responsible
323  * for tracking the valid offset.
324  *
325  * This function will build the DVSEC header on behalf of the caller and then
326  * copy in the remaining data for the vendor specific bits.
327  * It will also set up appropriate write masks.
328  */
329 void cxl_component_create_dvsec(CXLComponentState *cxl,
330                                 enum reg_type cxl_dev_type, uint16_t length,
331                                 uint16_t type, uint8_t rev, uint8_t *body)
332 {
333     PCIDevice *pdev = cxl->pdev;
334     uint16_t offset = cxl->dvsec_offset;
335     uint8_t *wmask = pdev->wmask;
336 
337     assert(offset >= PCI_CFG_SPACE_SIZE &&
338            ((offset + length) < PCI_CFG_SPACE_EXP_SIZE));
339     assert((length & 0xf000) == 0);
340     assert((rev & ~0xf) == 0);
341 
342     /* Create the DVSEC in the MCFG space */
343     pcie_add_capability(pdev, PCI_EXT_CAP_ID_DVSEC, 1, offset, length);
344     pci_set_long(pdev->config + offset + PCIE_DVSEC_HEADER1_OFFSET,
345                  (length << 20) | (rev << 16) | CXL_VENDOR_ID);
346     pci_set_word(pdev->config + offset + PCIE_DVSEC_ID_OFFSET, type);
347     memcpy(pdev->config + offset + sizeof(DVSECHeader),
348            body + sizeof(DVSECHeader),
349            length - sizeof(DVSECHeader));
350 
351     /* Configure write masks */
352     switch (type) {
353     case PCIE_CXL_DEVICE_DVSEC:
354         /* Cntrl RW Lock - so needs explicit blocking when lock is set */
355         wmask[offset + offsetof(CXLDVSECDevice, ctrl)] = 0xFD;
356         wmask[offset + offsetof(CXLDVSECDevice, ctrl) + 1] = 0x4F;
357         /* Status is RW1CS */
358         wmask[offset + offsetof(CXLDVSECDevice, ctrl2)] = 0x0F;
359        /* Lock is RW Once */
360         wmask[offset + offsetof(CXLDVSECDevice, lock)] = 0x01;
361         /* range1/2_base_high/low is RW Lock */
362         wmask[offset + offsetof(CXLDVSECDevice, range1_base_hi)] = 0xFF;
363         wmask[offset + offsetof(CXLDVSECDevice, range1_base_hi) + 1] = 0xFF;
364         wmask[offset + offsetof(CXLDVSECDevice, range1_base_hi) + 2] = 0xFF;
365         wmask[offset + offsetof(CXLDVSECDevice, range1_base_hi) + 3] = 0xFF;
366         wmask[offset + offsetof(CXLDVSECDevice, range1_base_lo) + 3] = 0xF0;
367         wmask[offset + offsetof(CXLDVSECDevice, range2_base_hi)] = 0xFF;
368         wmask[offset + offsetof(CXLDVSECDevice, range2_base_hi) + 1] = 0xFF;
369         wmask[offset + offsetof(CXLDVSECDevice, range2_base_hi) + 2] = 0xFF;
370         wmask[offset + offsetof(CXLDVSECDevice, range2_base_hi) + 3] = 0xFF;
371         wmask[offset + offsetof(CXLDVSECDevice, range2_base_lo) + 3] = 0xF0;
372         break;
373     case NON_CXL_FUNCTION_MAP_DVSEC:
374         break; /* Not yet implemented */
375     case EXTENSIONS_PORT_DVSEC:
376         wmask[offset + offsetof(CXLDVSECPortExtensions, control)] = 0x0F;
377         wmask[offset + offsetof(CXLDVSECPortExtensions, control) + 1] = 0x40;
378         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_bus_base)] = 0xFF;
379         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_bus_limit)] = 0xFF;
380         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_memory_base)] = 0xF0;
381         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_memory_base) + 1] = 0xFF;
382         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_memory_limit)] = 0xF0;
383         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_memory_limit) + 1] = 0xFF;
384         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_base)] = 0xF0;
385         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_base) + 1] = 0xFF;
386         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_limit)] = 0xF0;
387         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_limit) + 1] = 0xFF;
388         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_base_high)] = 0xFF;
389         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_base_high) + 1] = 0xFF;
390         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_base_high) + 2] = 0xFF;
391         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_base_high) + 3] = 0xFF;
392         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_limit_high)] = 0xFF;
393         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_limit_high) + 1] = 0xFF;
394         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_limit_high) + 2] = 0xFF;
395         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_limit_high) + 3] = 0xFF;
396         break;
397     case GPF_PORT_DVSEC:
398         wmask[offset + offsetof(CXLDVSECPortGPF, phase1_ctrl)] = 0x0F;
399         wmask[offset + offsetof(CXLDVSECPortGPF, phase1_ctrl) + 1] = 0x0F;
400         wmask[offset + offsetof(CXLDVSECPortGPF, phase2_ctrl)] = 0x0F;
401         wmask[offset + offsetof(CXLDVSECPortGPF, phase2_ctrl) + 1] = 0x0F;
402         break;
403     case GPF_DEVICE_DVSEC:
404         wmask[offset + offsetof(CXLDVSECDeviceGPF, phase2_duration)] = 0x0F;
405         wmask[offset + offsetof(CXLDVSECDeviceGPF, phase2_duration) + 1] = 0x0F;
406         wmask[offset + offsetof(CXLDVSECDeviceGPF, phase2_power)] = 0xFF;
407         wmask[offset + offsetof(CXLDVSECDeviceGPF, phase2_power) + 1] = 0xFF;
408         wmask[offset + offsetof(CXLDVSECDeviceGPF, phase2_power) + 2] = 0xFF;
409         wmask[offset + offsetof(CXLDVSECDeviceGPF, phase2_power) + 3] = 0xFF;
410         break;
411     case PCIE_FLEXBUS_PORT_DVSEC:
412         switch (cxl_dev_type) {
413         case CXL2_ROOT_PORT:
414             /* No MLD */
415             wmask[offset + offsetof(CXLDVSECPortFlexBus, ctrl)] = 0xbd;
416             break;
417         case CXL2_DOWNSTREAM_PORT:
418             wmask[offset + offsetof(CXLDVSECPortFlexBus, ctrl)] = 0xfd;
419             break;
420         default: /* Registers are RO for other component types */
421             break;
422         }
423         /* There are rw1cs bits in the status register but never set currently */
424         break;
425     }
426 
427     /* Update state for future DVSEC additions */
428     range_init_nofail(&cxl->dvsecs[type], cxl->dvsec_offset, length);
429     cxl->dvsec_offset += length;
430 }
431 
432 /* CXL r3.0 Section 8.2.4.19.7 CXL HDM Decoder n Control Register */
433 uint8_t cxl_interleave_ways_enc(int iw, Error **errp)
434 {
435     switch (iw) {
436     case 1: return 0x0;
437     case 2: return 0x1;
438     case 4: return 0x2;
439     case 8: return 0x3;
440     case 16: return 0x4;
441     case 3: return 0x8;
442     case 6: return 0x9;
443     case 12: return 0xa;
444     default:
445         error_setg(errp, "Interleave ways: %d not supported", iw);
446         return 0;
447     }
448 }
449 
450 int cxl_interleave_ways_dec(uint8_t iw_enc, Error **errp)
451 {
452     switch (iw_enc) {
453     case 0x0: return 1;
454     case 0x1: return 2;
455     case 0x2: return 4;
456     case 0x3: return 8;
457     case 0x4: return 16;
458     case 0x8: return 3;
459     case 0x9: return 6;
460     case 0xa: return 12;
461     default:
462         error_setg(errp, "Encoded interleave ways: %d not supported", iw_enc);
463         return 0;
464     }
465 }
466 
467 uint8_t cxl_interleave_granularity_enc(uint64_t gran, Error **errp)
468 {
469     switch (gran) {
470     case 256: return 0;
471     case 512: return 1;
472     case 1024: return 2;
473     case 2048: return 3;
474     case 4096: return 4;
475     case 8192: return 5;
476     case 16384: return 6;
477     default:
478         error_setg(errp, "Interleave granularity: %" PRIu64 " invalid", gran);
479         return 0;
480     }
481 }
482