xref: /openbmc/qemu/hw/cxl/cxl-component-utils.c (revision d525f73f)
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 static uint64_t cxl_cache_mem_read_reg(void *opaque, hwaddr offset,
17                                        unsigned size)
18 {
19     CXLComponentState *cxl_cstate = opaque;
20     ComponentRegisters *cregs = &cxl_cstate->crb;
21 
22     if (size == 8) {
23         qemu_log_mask(LOG_UNIMP,
24                       "CXL 8 byte cache mem registers not implemented\n");
25         return 0;
26     }
27 
28     if (cregs->special_ops && cregs->special_ops->read) {
29         return cregs->special_ops->read(cxl_cstate, offset, size);
30     } else {
31         return cregs->cache_mem_registers[offset / sizeof(*cregs->cache_mem_registers)];
32     }
33 }
34 
35 static void dumb_hdm_handler(CXLComponentState *cxl_cstate, hwaddr offset,
36                              uint32_t value)
37 {
38     ComponentRegisters *cregs = &cxl_cstate->crb;
39     uint32_t *cache_mem = cregs->cache_mem_registers;
40     bool should_commit = false;
41 
42     switch (offset) {
43     case A_CXL_HDM_DECODER0_CTRL:
44         should_commit = FIELD_EX32(value, CXL_HDM_DECODER0_CTRL, COMMIT);
45         break;
46     default:
47         break;
48     }
49 
50     memory_region_transaction_begin();
51     stl_le_p((uint8_t *)cache_mem + offset, value);
52     if (should_commit) {
53         ARRAY_FIELD_DP32(cache_mem, CXL_HDM_DECODER0_CTRL, COMMIT, 0);
54         ARRAY_FIELD_DP32(cache_mem, CXL_HDM_DECODER0_CTRL, ERR, 0);
55         ARRAY_FIELD_DP32(cache_mem, CXL_HDM_DECODER0_CTRL, COMMITTED, 1);
56     }
57     memory_region_transaction_commit();
58 }
59 
60 static void cxl_cache_mem_write_reg(void *opaque, hwaddr offset, uint64_t value,
61                                     unsigned size)
62 {
63     CXLComponentState *cxl_cstate = opaque;
64     ComponentRegisters *cregs = &cxl_cstate->crb;
65     uint32_t mask;
66 
67     if (size == 8) {
68         qemu_log_mask(LOG_UNIMP,
69                       "CXL 8 byte cache mem registers not implemented\n");
70         return;
71     }
72     mask = cregs->cache_mem_regs_write_mask[offset / sizeof(*cregs->cache_mem_regs_write_mask)];
73     value &= mask;
74     /* RO bits should remain constant. Done by reading existing value */
75     value |= ~mask & cregs->cache_mem_registers[offset / sizeof(*cregs->cache_mem_registers)];
76     if (cregs->special_ops && cregs->special_ops->write) {
77         cregs->special_ops->write(cxl_cstate, offset, value, size);
78         return;
79     }
80 
81     if (offset >= A_CXL_HDM_DECODER_CAPABILITY &&
82         offset <= A_CXL_HDM_DECODER0_TARGET_LIST_HI) {
83         dumb_hdm_handler(cxl_cstate, offset, value);
84     } else {
85         cregs->cache_mem_registers[offset / sizeof(*cregs->cache_mem_registers)] = value;
86     }
87 }
88 
89 /*
90  * 8.2.3
91  *   The access restrictions specified in Section 8.2.2 also apply to CXL 2.0
92  *   Component Registers.
93  *
94  * 8.2.2
95  *   • A 32 bit register shall be accessed as a 4 Bytes quantity. Partial
96  *   reads are not permitted.
97  *   • A 64 bit register shall be accessed as a 8 Bytes quantity. Partial
98  *   reads are not permitted.
99  *
100  * As of the spec defined today, only 4 byte registers exist.
101  */
102 static const MemoryRegionOps cache_mem_ops = {
103     .read = cxl_cache_mem_read_reg,
104     .write = cxl_cache_mem_write_reg,
105     .endianness = DEVICE_LITTLE_ENDIAN,
106     .valid = {
107         .min_access_size = 4,
108         .max_access_size = 8,
109         .unaligned = false,
110     },
111     .impl = {
112         .min_access_size = 4,
113         .max_access_size = 8,
114     },
115 };
116 
117 void cxl_component_register_block_init(Object *obj,
118                                        CXLComponentState *cxl_cstate,
119                                        const char *type)
120 {
121     ComponentRegisters *cregs = &cxl_cstate->crb;
122 
123     memory_region_init(&cregs->component_registers, obj, type,
124                        CXL2_COMPONENT_BLOCK_SIZE);
125 
126     /* io registers controls link which we don't care about in QEMU */
127     memory_region_init_io(&cregs->io, obj, NULL, cregs, ".io",
128                           CXL2_COMPONENT_IO_REGION_SIZE);
129     memory_region_init_io(&cregs->cache_mem, obj, &cache_mem_ops, cregs,
130                           ".cache_mem", CXL2_COMPONENT_CM_REGION_SIZE);
131 
132     memory_region_add_subregion(&cregs->component_registers, 0, &cregs->io);
133     memory_region_add_subregion(&cregs->component_registers,
134                                 CXL2_COMPONENT_IO_REGION_SIZE,
135                                 &cregs->cache_mem);
136 }
137 
138 static void ras_init_common(uint32_t *reg_state, uint32_t *write_msk)
139 {
140     /*
141      * Error status is RW1C but given bits are not yet set, it can
142      * be handled as RO.
143      */
144     reg_state[R_CXL_RAS_UNC_ERR_STATUS] = 0;
145     /* Bits 12-13 and 17-31 reserved in CXL 2.0 */
146     reg_state[R_CXL_RAS_UNC_ERR_MASK] = 0x1cfff;
147     write_msk[R_CXL_RAS_UNC_ERR_MASK] = 0x1cfff;
148     reg_state[R_CXL_RAS_UNC_ERR_SEVERITY] = 0x1cfff;
149     write_msk[R_CXL_RAS_UNC_ERR_SEVERITY] = 0x1cfff;
150     reg_state[R_CXL_RAS_COR_ERR_STATUS] = 0;
151     reg_state[R_CXL_RAS_COR_ERR_MASK] = 0x7f;
152     write_msk[R_CXL_RAS_COR_ERR_MASK] = 0x7f;
153     /* CXL switches and devices must set */
154     reg_state[R_CXL_RAS_ERR_CAP_CTRL] = 0x00;
155 }
156 
157 static void hdm_init_common(uint32_t *reg_state, uint32_t *write_msk,
158                             enum reg_type type)
159 {
160     int decoder_count = 1;
161     int i;
162 
163     ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_CAPABILITY, DECODER_COUNT,
164                      cxl_decoder_count_enc(decoder_count));
165     ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_CAPABILITY, TARGET_COUNT, 1);
166     ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_CAPABILITY, INTERLEAVE_256B, 1);
167     ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_CAPABILITY, INTERLEAVE_4K, 1);
168     ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_CAPABILITY, POISON_ON_ERR_CAP, 0);
169     ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_GLOBAL_CONTROL,
170                      HDM_DECODER_ENABLE, 0);
171     write_msk[R_CXL_HDM_DECODER_GLOBAL_CONTROL] = 0x3;
172     for (i = 0; i < decoder_count; i++) {
173         write_msk[R_CXL_HDM_DECODER0_BASE_LO + i * 0x20] = 0xf0000000;
174         write_msk[R_CXL_HDM_DECODER0_BASE_HI + i * 0x20] = 0xffffffff;
175         write_msk[R_CXL_HDM_DECODER0_SIZE_LO + i * 0x20] = 0xf0000000;
176         write_msk[R_CXL_HDM_DECODER0_SIZE_HI + i * 0x20] = 0xffffffff;
177         write_msk[R_CXL_HDM_DECODER0_CTRL + i * 0x20] = 0x13ff;
178         if (type == CXL2_DEVICE ||
179             type == CXL2_TYPE3_DEVICE ||
180             type == CXL2_LOGICAL_DEVICE) {
181             write_msk[R_CXL_HDM_DECODER0_TARGET_LIST_LO + i * 0x20] = 0xf0000000;
182         } else {
183             write_msk[R_CXL_HDM_DECODER0_TARGET_LIST_LO + i * 0x20] = 0xffffffff;
184         }
185         write_msk[R_CXL_HDM_DECODER0_TARGET_LIST_HI + i * 0x20] = 0xffffffff;
186     }
187 }
188 
189 void cxl_component_register_init_common(uint32_t *reg_state, uint32_t *write_msk,
190                                         enum reg_type type)
191 {
192     int caps = 0;
193 
194     /*
195      * In CXL 2.0 the capabilities required for each CXL component are such that,
196      * with the ordering chosen here, a single number can be used to define
197      * which capabilities should be provided.
198      */
199     switch (type) {
200     case CXL2_DOWNSTREAM_PORT:
201     case CXL2_DEVICE:
202         /* RAS, Link */
203         caps = 2;
204         break;
205     case CXL2_UPSTREAM_PORT:
206     case CXL2_TYPE3_DEVICE:
207     case CXL2_LOGICAL_DEVICE:
208         /* + HDM */
209         caps = 3;
210         break;
211     case CXL2_ROOT_PORT:
212         /* + Extended Security, + Snoop */
213         caps = 5;
214         break;
215     default:
216         abort();
217     }
218 
219     memset(reg_state, 0, CXL2_COMPONENT_CM_REGION_SIZE);
220 
221     /* CXL Capability Header Register */
222     ARRAY_FIELD_DP32(reg_state, CXL_CAPABILITY_HEADER, ID, 1);
223     ARRAY_FIELD_DP32(reg_state, CXL_CAPABILITY_HEADER, VERSION, 1);
224     ARRAY_FIELD_DP32(reg_state, CXL_CAPABILITY_HEADER, CACHE_MEM_VERSION, 1);
225     ARRAY_FIELD_DP32(reg_state, CXL_CAPABILITY_HEADER, ARRAY_SIZE, caps);
226 
227 #define init_cap_reg(reg, id, version)                                        \
228     QEMU_BUILD_BUG_ON(CXL_##reg##_REGISTERS_OFFSET == 0);                     \
229     do {                                                                      \
230         int which = R_CXL_##reg##_CAPABILITY_HEADER;                          \
231         reg_state[which] = FIELD_DP32(reg_state[which],                       \
232                                       CXL_##reg##_CAPABILITY_HEADER, ID, id); \
233         reg_state[which] =                                                    \
234             FIELD_DP32(reg_state[which], CXL_##reg##_CAPABILITY_HEADER,       \
235                        VERSION, version);                                     \
236         reg_state[which] =                                                    \
237             FIELD_DP32(reg_state[which], CXL_##reg##_CAPABILITY_HEADER, PTR,  \
238                        CXL_##reg##_REGISTERS_OFFSET);                         \
239     } while (0)
240 
241     init_cap_reg(RAS, 2, 2);
242     ras_init_common(reg_state, write_msk);
243 
244     init_cap_reg(LINK, 4, 2);
245 
246     if (caps < 3) {
247         return;
248     }
249 
250     init_cap_reg(HDM, 5, 1);
251     hdm_init_common(reg_state, write_msk, type);
252 
253     if (caps < 5) {
254         return;
255     }
256 
257     init_cap_reg(EXTSEC, 6, 1);
258     init_cap_reg(SNOOP, 8, 1);
259 
260 #undef init_cap_reg
261 }
262 
263 /*
264  * Helper to creates a DVSEC header for a CXL entity. The caller is responsible
265  * for tracking the valid offset.
266  *
267  * This function will build the DVSEC header on behalf of the caller and then
268  * copy in the remaining data for the vendor specific bits.
269  * It will also set up appropriate write masks.
270  */
271 void cxl_component_create_dvsec(CXLComponentState *cxl,
272                                 enum reg_type cxl_dev_type, uint16_t length,
273                                 uint16_t type, uint8_t rev, uint8_t *body)
274 {
275     PCIDevice *pdev = cxl->pdev;
276     uint16_t offset = cxl->dvsec_offset;
277     uint8_t *wmask = pdev->wmask;
278 
279     assert(offset >= PCI_CFG_SPACE_SIZE &&
280            ((offset + length) < PCI_CFG_SPACE_EXP_SIZE));
281     assert((length & 0xf000) == 0);
282     assert((rev & ~0xf) == 0);
283 
284     /* Create the DVSEC in the MCFG space */
285     pcie_add_capability(pdev, PCI_EXT_CAP_ID_DVSEC, 1, offset, length);
286     pci_set_long(pdev->config + offset + PCIE_DVSEC_HEADER1_OFFSET,
287                  (length << 20) | (rev << 16) | CXL_VENDOR_ID);
288     pci_set_word(pdev->config + offset + PCIE_DVSEC_ID_OFFSET, type);
289     memcpy(pdev->config + offset + sizeof(DVSECHeader),
290            body + sizeof(DVSECHeader),
291            length - sizeof(DVSECHeader));
292 
293     /* Configure write masks */
294     switch (type) {
295     case PCIE_CXL_DEVICE_DVSEC:
296         /* Cntrl RW Lock - so needs explicit blocking when lock is set */
297         wmask[offset + offsetof(CXLDVSECDevice, ctrl)] = 0xFD;
298         wmask[offset + offsetof(CXLDVSECDevice, ctrl) + 1] = 0x4F;
299         /* Status is RW1CS */
300         wmask[offset + offsetof(CXLDVSECDevice, ctrl2)] = 0x0F;
301        /* Lock is RW Once */
302         wmask[offset + offsetof(CXLDVSECDevice, lock)] = 0x01;
303         /* range1/2_base_high/low is RW Lock */
304         wmask[offset + offsetof(CXLDVSECDevice, range1_base_hi)] = 0xFF;
305         wmask[offset + offsetof(CXLDVSECDevice, range1_base_hi) + 1] = 0xFF;
306         wmask[offset + offsetof(CXLDVSECDevice, range1_base_hi) + 2] = 0xFF;
307         wmask[offset + offsetof(CXLDVSECDevice, range1_base_hi) + 3] = 0xFF;
308         wmask[offset + offsetof(CXLDVSECDevice, range1_base_lo) + 3] = 0xF0;
309         wmask[offset + offsetof(CXLDVSECDevice, range2_base_hi)] = 0xFF;
310         wmask[offset + offsetof(CXLDVSECDevice, range2_base_hi) + 1] = 0xFF;
311         wmask[offset + offsetof(CXLDVSECDevice, range2_base_hi) + 2] = 0xFF;
312         wmask[offset + offsetof(CXLDVSECDevice, range2_base_hi) + 3] = 0xFF;
313         wmask[offset + offsetof(CXLDVSECDevice, range2_base_lo) + 3] = 0xF0;
314         break;
315     case NON_CXL_FUNCTION_MAP_DVSEC:
316         break; /* Not yet implemented */
317     case EXTENSIONS_PORT_DVSEC:
318         wmask[offset + offsetof(CXLDVSECPortExtensions, control)] = 0x0F;
319         wmask[offset + offsetof(CXLDVSECPortExtensions, control) + 1] = 0x40;
320         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_bus_base)] = 0xFF;
321         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_bus_limit)] = 0xFF;
322         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_memory_base)] = 0xF0;
323         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_memory_base) + 1] = 0xFF;
324         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_memory_limit)] = 0xF0;
325         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_memory_limit) + 1] = 0xFF;
326         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_base)] = 0xF0;
327         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_base) + 1] = 0xFF;
328         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_limit)] = 0xF0;
329         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_limit) + 1] = 0xFF;
330         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_base_high)] = 0xFF;
331         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_base_high) + 1] = 0xFF;
332         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_base_high) + 2] = 0xFF;
333         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_base_high) + 3] = 0xFF;
334         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_limit_high)] = 0xFF;
335         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_limit_high) + 1] = 0xFF;
336         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_limit_high) + 2] = 0xFF;
337         wmask[offset + offsetof(CXLDVSECPortExtensions, alt_prefetch_limit_high) + 3] = 0xFF;
338         break;
339     case GPF_PORT_DVSEC:
340         wmask[offset + offsetof(CXLDVSECPortGPF, phase1_ctrl)] = 0x0F;
341         wmask[offset + offsetof(CXLDVSECPortGPF, phase1_ctrl) + 1] = 0x0F;
342         wmask[offset + offsetof(CXLDVSECPortGPF, phase2_ctrl)] = 0x0F;
343         wmask[offset + offsetof(CXLDVSECPortGPF, phase2_ctrl) + 1] = 0x0F;
344         break;
345     case GPF_DEVICE_DVSEC:
346         wmask[offset + offsetof(CXLDVSECDeviceGPF, phase2_duration)] = 0x0F;
347         wmask[offset + offsetof(CXLDVSECDeviceGPF, phase2_duration) + 1] = 0x0F;
348         wmask[offset + offsetof(CXLDVSECDeviceGPF, phase2_power)] = 0xFF;
349         wmask[offset + offsetof(CXLDVSECDeviceGPF, phase2_power) + 1] = 0xFF;
350         wmask[offset + offsetof(CXLDVSECDeviceGPF, phase2_power) + 2] = 0xFF;
351         wmask[offset + offsetof(CXLDVSECDeviceGPF, phase2_power) + 3] = 0xFF;
352         break;
353     case PCIE_FLEXBUS_PORT_DVSEC:
354         switch (cxl_dev_type) {
355         case CXL2_ROOT_PORT:
356             /* No MLD */
357             wmask[offset + offsetof(CXLDVSECPortFlexBus, ctrl)] = 0xbd;
358             break;
359         case CXL2_DOWNSTREAM_PORT:
360             wmask[offset + offsetof(CXLDVSECPortFlexBus, ctrl)] = 0xfd;
361             break;
362         default: /* Registers are RO for other component types */
363             break;
364         }
365         /* There are rw1cs bits in the status register but never set currently */
366         break;
367     }
368 
369     /* Update state for future DVSEC additions */
370     range_init_nofail(&cxl->dvsecs[type], cxl->dvsec_offset, length);
371     cxl->dvsec_offset += length;
372 }
373 
374 uint8_t cxl_interleave_ways_enc(int iw, Error **errp)
375 {
376     switch (iw) {
377     case 1: return 0x0;
378     case 2: return 0x1;
379     case 4: return 0x2;
380     case 8: return 0x3;
381     case 16: return 0x4;
382     case 3: return 0x8;
383     case 6: return 0x9;
384     case 12: return 0xa;
385     default:
386         error_setg(errp, "Interleave ways: %d not supported", iw);
387         return 0;
388     }
389 }
390 
391 uint8_t cxl_interleave_granularity_enc(uint64_t gran, Error **errp)
392 {
393     switch (gran) {
394     case 256: return 0;
395     case 512: return 1;
396     case 1024: return 2;
397     case 2048: return 3;
398     case 4096: return 4;
399     case 8192: return 5;
400     case 16384: return 6;
401     default:
402         error_setg(errp, "Interleave granularity: %" PRIu64 " invalid", gran);
403         return 0;
404     }
405 }
406