xref: /openbmc/qemu/hw/pci-bridge/cxl_upstream.c (revision 35bafa95)
1 /*
2  * Emulated CXL Switch Upstream Port
3  *
4  * Copyright (c) 2022 Huawei Technologies.
5  *
6  * Based on xio3130_upstream.c
7  *
8  * SPDX-License-Identifier: GPL-2.0-or-later
9  */
10 
11 #include "qemu/osdep.h"
12 #include "qemu/log.h"
13 #include "hw/qdev-properties.h"
14 #include "hw/pci/msi.h"
15 #include "hw/pci/pcie.h"
16 #include "hw/pci/pcie_port.h"
17 /*
18  * Null value of all Fs suggested by IEEE RA guidelines for use of
19  * EU, OUI and CID
20  */
21 #define UI64_NULL (~0ULL)
22 
23 #define CXL_UPSTREAM_PORT_MSI_NR_VECTOR 2
24 
25 #define CXL_UPSTREAM_PORT_MSI_OFFSET 0x70
26 #define CXL_UPSTREAM_PORT_PCIE_CAP_OFFSET 0x90
27 #define CXL_UPSTREAM_PORT_AER_OFFSET 0x100
28 #define CXL_UPSTREAM_PORT_SN_OFFSET \
29     (CXL_UPSTREAM_PORT_AER_OFFSET + PCI_ERR_SIZEOF)
30 #define CXL_UPSTREAM_PORT_DVSEC_OFFSET \
31     (CXL_UPSTREAM_PORT_SN_OFFSET + PCI_EXT_CAP_DSN_SIZEOF)
32 
33 typedef struct CXLUpstreamPort {
34     /*< private >*/
35     PCIEPort parent_obj;
36 
37     /*< public >*/
38     CXLComponentState cxl_cstate;
39     DOECap doe_cdat;
40     uint64_t sn;
41 } CXLUpstreamPort;
42 
43 CXLComponentState *cxl_usp_to_cstate(CXLUpstreamPort *usp)
44 {
45     return &usp->cxl_cstate;
46 }
47 
48 static void cxl_usp_dvsec_write_config(PCIDevice *dev, uint32_t addr,
49                                        uint32_t val, int len)
50 {
51     CXLUpstreamPort *usp = CXL_USP(dev);
52 
53     if (range_contains(&usp->cxl_cstate.dvsecs[EXTENSIONS_PORT_DVSEC], addr)) {
54         uint8_t *reg = &dev->config[addr];
55         addr -= usp->cxl_cstate.dvsecs[EXTENSIONS_PORT_DVSEC].lob;
56         if (addr == PORT_CONTROL_OFFSET) {
57             if (pci_get_word(reg) & PORT_CONTROL_UNMASK_SBR) {
58                 /* unmask SBR */
59                 qemu_log_mask(LOG_UNIMP, "SBR mask control is not supported\n");
60             }
61             if (pci_get_word(reg) & PORT_CONTROL_ALT_MEMID_EN) {
62                 /* Alt Memory & ID Space Enable */
63                 qemu_log_mask(LOG_UNIMP,
64                               "Alt Memory & ID space is not supported\n");
65             }
66         }
67     }
68 }
69 
70 static void cxl_usp_write_config(PCIDevice *d, uint32_t address,
71                                  uint32_t val, int len)
72 {
73     CXLUpstreamPort *usp = CXL_USP(d);
74 
75     pcie_doe_write_config(&usp->doe_cdat, address, val, len);
76     pci_bridge_write_config(d, address, val, len);
77     pcie_cap_flr_write_config(d, address, val, len);
78     pcie_aer_write_config(d, address, val, len);
79 
80     cxl_usp_dvsec_write_config(d, address, val, len);
81 }
82 
83 static uint32_t cxl_usp_read_config(PCIDevice *d, uint32_t address, int len)
84 {
85     CXLUpstreamPort *usp = CXL_USP(d);
86     uint32_t val;
87 
88     if (pcie_doe_read_config(&usp->doe_cdat, address, len, &val)) {
89         return val;
90     }
91 
92     return pci_default_read_config(d, address, len);
93 }
94 
95 static void latch_registers(CXLUpstreamPort *usp)
96 {
97     uint32_t *reg_state = usp->cxl_cstate.crb.cache_mem_registers;
98     uint32_t *write_msk = usp->cxl_cstate.crb.cache_mem_regs_write_mask;
99 
100     cxl_component_register_init_common(reg_state, write_msk,
101                                        CXL2_UPSTREAM_PORT);
102     ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_CAPABILITY, TARGET_COUNT, 8);
103 }
104 
105 static void cxl_usp_reset(DeviceState *qdev)
106 {
107     PCIDevice *d = PCI_DEVICE(qdev);
108     CXLUpstreamPort *usp = CXL_USP(qdev);
109 
110     pci_bridge_reset(qdev);
111     pcie_cap_deverr_reset(d);
112     latch_registers(usp);
113 }
114 
115 static void build_dvsecs(CXLComponentState *cxl)
116 {
117     uint8_t *dvsec;
118 
119     dvsec = (uint8_t *)&(CXLDVSECPortExtensions){
120         .status = 0x1, /* Port Power Management Init Complete */
121     };
122     cxl_component_create_dvsec(cxl, CXL2_UPSTREAM_PORT,
123                                EXTENSIONS_PORT_DVSEC_LENGTH,
124                                EXTENSIONS_PORT_DVSEC,
125                                EXTENSIONS_PORT_DVSEC_REVID, dvsec);
126     dvsec = (uint8_t *)&(CXLDVSECPortFlexBus){
127         .cap                     = 0x27, /* Cache, IO, Mem, non-MLD */
128         .ctrl                    = 0x27, /* Cache, IO, Mem */
129         .status                  = 0x26, /* same */
130         .rcvd_mod_ts_data_phase1 = 0xef, /* WTF? */
131     };
132     cxl_component_create_dvsec(cxl, CXL2_UPSTREAM_PORT,
133                                PCIE_FLEXBUS_PORT_DVSEC_LENGTH_2_0,
134                                PCIE_FLEXBUS_PORT_DVSEC,
135                                PCIE_FLEXBUS_PORT_DVSEC_REVID_2_0, dvsec);
136 
137     dvsec = (uint8_t *)&(CXLDVSECRegisterLocator){
138         .rsvd         = 0,
139         .reg0_base_lo = RBI_COMPONENT_REG | CXL_COMPONENT_REG_BAR_IDX,
140         .reg0_base_hi = 0,
141     };
142     cxl_component_create_dvsec(cxl, CXL2_UPSTREAM_PORT,
143                                REG_LOC_DVSEC_LENGTH, REG_LOC_DVSEC,
144                                REG_LOC_DVSEC_REVID, dvsec);
145 }
146 
147 static bool cxl_doe_cdat_rsp(DOECap *doe_cap)
148 {
149     CDATObject *cdat = &CXL_USP(doe_cap->pdev)->cxl_cstate.cdat;
150     uint16_t ent;
151     void *base;
152     uint32_t len;
153     CDATReq *req = pcie_doe_get_write_mbox_ptr(doe_cap);
154     CDATRsp rsp;
155 
156     cxl_doe_cdat_update(&CXL_USP(doe_cap->pdev)->cxl_cstate, &error_fatal);
157     assert(cdat->entry_len);
158 
159     /* Discard if request length mismatched */
160     if (pcie_doe_get_obj_len(req) <
161         DIV_ROUND_UP(sizeof(CDATReq), sizeof(uint32_t))) {
162         return false;
163     }
164 
165     ent = req->entry_handle;
166     base = cdat->entry[ent].base;
167     len = cdat->entry[ent].length;
168 
169     rsp = (CDATRsp) {
170         .header = {
171             .vendor_id = CXL_VENDOR_ID,
172             .data_obj_type = CXL_DOE_TABLE_ACCESS,
173             .reserved = 0x0,
174             .length = DIV_ROUND_UP((sizeof(rsp) + len), sizeof(uint32_t)),
175         },
176         .rsp_code = CXL_DOE_TAB_RSP,
177         .table_type = CXL_DOE_TAB_TYPE_CDAT,
178         .entry_handle = (ent < cdat->entry_len - 1) ?
179                         ent + 1 : CXL_DOE_TAB_ENT_MAX,
180     };
181 
182     memcpy(doe_cap->read_mbox, &rsp, sizeof(rsp));
183         memcpy(doe_cap->read_mbox + DIV_ROUND_UP(sizeof(rsp), sizeof(uint32_t)),
184            base, len);
185 
186     doe_cap->read_mbox_len += rsp.header.length;
187 
188     return true;
189 }
190 
191 static DOEProtocol doe_cdat_prot[] = {
192     { CXL_VENDOR_ID, CXL_DOE_TABLE_ACCESS, cxl_doe_cdat_rsp },
193     { }
194 };
195 
196 enum {
197     CXL_USP_CDAT_SSLBIS_LAT,
198     CXL_USP_CDAT_SSLBIS_BW,
199     CXL_USP_CDAT_NUM_ENTRIES
200 };
201 
202 static int build_cdat_table(CDATSubHeader ***cdat_table, void *priv)
203 {
204     g_autofree CDATSslbis *sslbis_latency = NULL;
205     g_autofree CDATSslbis *sslbis_bandwidth = NULL;
206     CXLUpstreamPort *us = CXL_USP(priv);
207     PCIBus *bus = &PCI_BRIDGE(us)->sec_bus;
208     int devfn, sslbis_size, i;
209     int count = 0;
210     uint16_t port_ids[256];
211 
212     for (devfn = 0; devfn < ARRAY_SIZE(bus->devices); devfn++) {
213         PCIDevice *d = bus->devices[devfn];
214         PCIEPort *port;
215 
216         if (!d || !pci_is_express(d) || !d->exp.exp_cap) {
217             continue;
218         }
219 
220         /*
221          * Whilst the PCI express spec doesn't allow anything other than
222          * downstream ports on this bus, let us be a little paranoid
223          */
224         if (!object_dynamic_cast(OBJECT(d), TYPE_PCIE_PORT)) {
225             continue;
226         }
227 
228         port = PCIE_PORT(d);
229         port_ids[count] = port->port;
230         count++;
231     }
232 
233     /* May not yet have any ports - try again later */
234     if (count == 0) {
235         return 0;
236     }
237 
238     sslbis_size = sizeof(CDATSslbis) + sizeof(*sslbis_latency->sslbe) * count;
239     sslbis_latency = g_malloc(sslbis_size);
240     if (!sslbis_latency) {
241         return -ENOMEM;
242     }
243     *sslbis_latency = (CDATSslbis) {
244         .sslbis_header = {
245             .header = {
246                 .type = CDAT_TYPE_SSLBIS,
247                 .length = sslbis_size,
248             },
249             .data_type = HMATLB_DATA_TYPE_ACCESS_LATENCY,
250             .entry_base_unit = 10000,
251         },
252     };
253 
254     for (i = 0; i < count; i++) {
255         sslbis_latency->sslbe[i] = (CDATSslbe) {
256             .port_x_id = CDAT_PORT_ID_USP,
257             .port_y_id = port_ids[i],
258             .latency_bandwidth = 15, /* 150ns */
259         };
260     }
261 
262     sslbis_bandwidth = g_malloc(sslbis_size);
263     if (!sslbis_bandwidth) {
264         return 0;
265     }
266     *sslbis_bandwidth = (CDATSslbis) {
267         .sslbis_header = {
268             .header = {
269                 .type = CDAT_TYPE_SSLBIS,
270                 .length = sslbis_size,
271             },
272             .data_type = HMATLB_DATA_TYPE_ACCESS_BANDWIDTH,
273             .entry_base_unit = 1024,
274         },
275     };
276 
277     for (i = 0; i < count; i++) {
278         sslbis_bandwidth->sslbe[i] = (CDATSslbe) {
279             .port_x_id = CDAT_PORT_ID_USP,
280             .port_y_id = port_ids[i],
281             .latency_bandwidth = 16, /* 16 GB/s */
282         };
283     }
284 
285     *cdat_table = g_new0(CDATSubHeader *, CXL_USP_CDAT_NUM_ENTRIES);
286 
287     /* Header always at start of structure */
288     (*cdat_table)[CXL_USP_CDAT_SSLBIS_LAT] = g_steal_pointer(&sslbis_latency);
289     (*cdat_table)[CXL_USP_CDAT_SSLBIS_BW] = g_steal_pointer(&sslbis_bandwidth);
290 
291     return CXL_USP_CDAT_NUM_ENTRIES;
292 }
293 
294 static void free_default_cdat_table(CDATSubHeader **cdat_table, int num,
295                                     void *priv)
296 {
297     int i;
298 
299     for (i = 0; i < num; i++) {
300         g_free(cdat_table[i]);
301     }
302     g_free(cdat_table);
303 }
304 
305 static void cxl_usp_realize(PCIDevice *d, Error **errp)
306 {
307     PCIEPort *p = PCIE_PORT(d);
308     CXLUpstreamPort *usp = CXL_USP(d);
309     CXLComponentState *cxl_cstate = &usp->cxl_cstate;
310     ComponentRegisters *cregs = &cxl_cstate->crb;
311     MemoryRegion *component_bar = &cregs->component_registers;
312     int rc;
313 
314     pci_bridge_initfn(d, TYPE_PCIE_BUS);
315     pcie_port_init_reg(d);
316 
317     rc = msi_init(d, CXL_UPSTREAM_PORT_MSI_OFFSET,
318                   CXL_UPSTREAM_PORT_MSI_NR_VECTOR, true, true, errp);
319     if (rc) {
320         assert(rc == -ENOTSUP);
321         goto err_bridge;
322     }
323 
324     rc = pcie_cap_init(d, CXL_UPSTREAM_PORT_PCIE_CAP_OFFSET,
325                        PCI_EXP_TYPE_UPSTREAM, p->port, errp);
326     if (rc < 0) {
327         goto err_msi;
328     }
329 
330     pcie_cap_flr_init(d);
331     pcie_cap_deverr_init(d);
332     rc = pcie_aer_init(d, PCI_ERR_VER, CXL_UPSTREAM_PORT_AER_OFFSET,
333                        PCI_ERR_SIZEOF, errp);
334     if (rc) {
335         goto err_cap;
336     }
337     if (usp->sn != UI64_NULL) {
338         pcie_dev_ser_num_init(d, CXL_UPSTREAM_PORT_SN_OFFSET, usp->sn);
339     }
340     cxl_cstate->dvsec_offset = CXL_UPSTREAM_PORT_DVSEC_OFFSET;
341     cxl_cstate->pdev = d;
342     build_dvsecs(cxl_cstate);
343     cxl_component_register_block_init(OBJECT(d), cxl_cstate, TYPE_CXL_USP);
344     pci_register_bar(d, CXL_COMPONENT_REG_BAR_IDX,
345                      PCI_BASE_ADDRESS_SPACE_MEMORY |
346                      PCI_BASE_ADDRESS_MEM_TYPE_64,
347                      component_bar);
348 
349     pcie_doe_init(d, &usp->doe_cdat, cxl_cstate->dvsec_offset, doe_cdat_prot,
350                   true, 1);
351 
352     cxl_cstate->cdat.build_cdat_table = build_cdat_table;
353     cxl_cstate->cdat.free_cdat_table = free_default_cdat_table;
354     cxl_cstate->cdat.private = d;
355     cxl_doe_cdat_init(cxl_cstate, errp);
356     if (*errp) {
357         goto err_cap;
358     }
359 
360     return;
361 
362 err_cap:
363     pcie_cap_exit(d);
364 err_msi:
365     msi_uninit(d);
366 err_bridge:
367     pci_bridge_exitfn(d);
368 }
369 
370 static void cxl_usp_exitfn(PCIDevice *d)
371 {
372     pcie_aer_exit(d);
373     pcie_cap_exit(d);
374     msi_uninit(d);
375     pci_bridge_exitfn(d);
376 }
377 
378 static Property cxl_upstream_props[] = {
379     DEFINE_PROP_UINT64("sn", CXLUpstreamPort, sn, UI64_NULL),
380     DEFINE_PROP_STRING("cdat", CXLUpstreamPort, cxl_cstate.cdat.filename),
381     DEFINE_PROP_END_OF_LIST()
382 };
383 
384 static void cxl_upstream_class_init(ObjectClass *oc, void *data)
385 {
386     DeviceClass *dc = DEVICE_CLASS(oc);
387     PCIDeviceClass *k = PCI_DEVICE_CLASS(oc);
388 
389     k->config_write = cxl_usp_write_config;
390     k->config_read = cxl_usp_read_config;
391     k->realize = cxl_usp_realize;
392     k->exit = cxl_usp_exitfn;
393     k->vendor_id = 0x19e5; /* Huawei */
394     k->device_id = 0xa128; /* Emulated CXL Switch Upstream Port */
395     k->revision = 0;
396     set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
397     dc->desc = "CXL Switch Upstream Port";
398     dc->reset = cxl_usp_reset;
399     device_class_set_props(dc, cxl_upstream_props);
400 }
401 
402 static const TypeInfo cxl_usp_info = {
403     .name = TYPE_CXL_USP,
404     .parent = TYPE_PCIE_PORT,
405     .instance_size = sizeof(CXLUpstreamPort),
406     .class_init = cxl_upstream_class_init,
407     .interfaces = (InterfaceInfo[]) {
408         { INTERFACE_PCIE_DEVICE },
409         { INTERFACE_CXL_DEVICE },
410         { }
411     },
412 };
413 
414 static void cxl_usp_register_type(void)
415 {
416     type_register_static(&cxl_usp_info);
417 }
418 
419 type_init(cxl_usp_register_type);
420