xref: /openbmc/qemu/hw/pci-bridge/cxl_root_port.c (revision 651ccdfa)
1 /*
2  * CXL 2.0 Root Port Implementation
3  *
4  * Copyright(C) 2020 Intel Corporation.
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, see <http://www.gnu.org/licenses/>
18  */
19 
20 #include "qemu/osdep.h"
21 #include "qemu/log.h"
22 #include "qemu/range.h"
23 #include "hw/pci/pci_bridge.h"
24 #include "hw/pci/pcie_port.h"
25 #include "hw/pci/msi.h"
26 #include "hw/qdev-properties.h"
27 #include "hw/sysbus.h"
28 #include "qapi/error.h"
29 #include "hw/cxl/cxl.h"
30 
31 #define CXL_ROOT_PORT_DID 0x7075
32 
33 #define CXL_RP_MSI_OFFSET               0x60
34 #define CXL_RP_MSI_SUPPORTED_FLAGS      PCI_MSI_FLAGS_MASKBIT
35 #define CXL_RP_MSI_NR_VECTOR            2
36 
37 /* Copied from the gen root port which we derive */
38 #define GEN_PCIE_ROOT_PORT_AER_OFFSET 0x100
39 #define GEN_PCIE_ROOT_PORT_ACS_OFFSET \
40     (GEN_PCIE_ROOT_PORT_AER_OFFSET + PCI_ERR_SIZEOF)
41 #define CXL_ROOT_PORT_DVSEC_OFFSET \
42     (GEN_PCIE_ROOT_PORT_ACS_OFFSET + PCI_ACS_SIZEOF)
43 
44 typedef struct CXLRootPort {
45     /*< private >*/
46     PCIESlot parent_obj;
47 
48     CXLComponentState cxl_cstate;
49     PCIResReserve res_reserve;
50 } CXLRootPort;
51 
52 #define TYPE_CXL_ROOT_PORT "cxl-rp"
53 DECLARE_INSTANCE_CHECKER(CXLRootPort, CXL_ROOT_PORT, TYPE_CXL_ROOT_PORT)
54 
55 /*
56  * If two MSI vector are allocated, Advanced Error Interrupt Message Number
57  * is 1. otherwise 0.
58  * 17.12.5.10 RPERRSTS,  32:27 bit Advanced Error Interrupt Message Number.
59  */
60 static uint8_t cxl_rp_aer_vector(const PCIDevice *d)
61 {
62     switch (msi_nr_vectors_allocated(d)) {
63     case 1:
64         return 0;
65     case 2:
66         return 1;
67     case 4:
68     case 8:
69     case 16:
70     case 32:
71     default:
72         break;
73     }
74     abort();
75     return 0;
76 }
77 
78 static int cxl_rp_interrupts_init(PCIDevice *d, Error **errp)
79 {
80     int rc;
81 
82     rc = msi_init(d, CXL_RP_MSI_OFFSET, CXL_RP_MSI_NR_VECTOR,
83                   CXL_RP_MSI_SUPPORTED_FLAGS & PCI_MSI_FLAGS_64BIT,
84                   CXL_RP_MSI_SUPPORTED_FLAGS & PCI_MSI_FLAGS_MASKBIT,
85                   errp);
86     if (rc < 0) {
87         assert(rc == -ENOTSUP);
88     }
89 
90     return rc;
91 }
92 
93 static void cxl_rp_interrupts_uninit(PCIDevice *d)
94 {
95     msi_uninit(d);
96 }
97 
98 static void latch_registers(CXLRootPort *crp)
99 {
100     uint32_t *reg_state = crp->cxl_cstate.crb.cache_mem_registers;
101     uint32_t *write_msk = crp->cxl_cstate.crb.cache_mem_regs_write_mask;
102 
103     cxl_component_register_init_common(reg_state, write_msk, CXL2_ROOT_PORT);
104 }
105 
106 static void build_dvsecs(CXLComponentState *cxl)
107 {
108     uint8_t *dvsec;
109 
110     dvsec = (uint8_t *)&(CXLDVSECPortExtensions){ 0 };
111     cxl_component_create_dvsec(cxl, CXL2_ROOT_PORT,
112                                EXTENSIONS_PORT_DVSEC_LENGTH,
113                                EXTENSIONS_PORT_DVSEC,
114                                EXTENSIONS_PORT_DVSEC_REVID, dvsec);
115 
116     dvsec = (uint8_t *)&(CXLDVSECPortGPF){
117         .rsvd        = 0,
118         .phase1_ctrl = 1, /* 1μs timeout */
119         .phase2_ctrl = 1, /* 1μs timeout */
120     };
121     cxl_component_create_dvsec(cxl, CXL2_ROOT_PORT,
122                                GPF_PORT_DVSEC_LENGTH, GPF_PORT_DVSEC,
123                                GPF_PORT_DVSEC_REVID, dvsec);
124 
125     dvsec = (uint8_t *)&(CXLDVSECPortFlexBus){
126         .cap                     = 0x26, /* IO, Mem, non-MLD */
127         .ctrl                    = 0x2,
128         .status                  = 0x26, /* same */
129         .rcvd_mod_ts_data_phase1 = 0xef,
130     };
131     cxl_component_create_dvsec(cxl, CXL2_ROOT_PORT,
132                                PCIE_FLEXBUS_PORT_DVSEC_LENGTH_2_0,
133                                PCIE_FLEXBUS_PORT_DVSEC,
134                                PCIE_FLEXBUS_PORT_DVSEC_REVID_2_0, dvsec);
135 
136     dvsec = (uint8_t *)&(CXLDVSECRegisterLocator){
137         .rsvd         = 0,
138         .reg0_base_lo = RBI_COMPONENT_REG | CXL_COMPONENT_REG_BAR_IDX,
139         .reg0_base_hi = 0,
140     };
141     cxl_component_create_dvsec(cxl, CXL2_ROOT_PORT,
142                                REG_LOC_DVSEC_LENGTH, REG_LOC_DVSEC,
143                                REG_LOC_DVSEC_REVID, dvsec);
144 }
145 
146 static void cxl_rp_realize(DeviceState *dev, Error **errp)
147 {
148     PCIDevice *pci_dev     = PCI_DEVICE(dev);
149     PCIERootPortClass *rpc = PCIE_ROOT_PORT_GET_CLASS(dev);
150     CXLRootPort *crp       = CXL_ROOT_PORT(dev);
151     CXLComponentState *cxl_cstate = &crp->cxl_cstate;
152     ComponentRegisters *cregs = &cxl_cstate->crb;
153     MemoryRegion *component_bar = &cregs->component_registers;
154     Error *local_err = NULL;
155 
156     rpc->parent_realize(dev, &local_err);
157     if (local_err) {
158         error_propagate(errp, local_err);
159         return;
160     }
161 
162     int rc =
163         pci_bridge_qemu_reserve_cap_init(pci_dev, 0, crp->res_reserve, errp);
164     if (rc < 0) {
165         rpc->parent_class.exit(pci_dev);
166         return;
167     }
168 
169     if (!crp->res_reserve.io || crp->res_reserve.io == -1) {
170         pci_word_test_and_clear_mask(pci_dev->wmask + PCI_COMMAND,
171                                      PCI_COMMAND_IO);
172         pci_dev->wmask[PCI_IO_BASE]  = 0;
173         pci_dev->wmask[PCI_IO_LIMIT] = 0;
174     }
175 
176     cxl_cstate->dvsec_offset = CXL_ROOT_PORT_DVSEC_OFFSET;
177     cxl_cstate->pdev = pci_dev;
178     build_dvsecs(&crp->cxl_cstate);
179 
180     cxl_component_register_block_init(OBJECT(pci_dev), cxl_cstate,
181                                       TYPE_CXL_ROOT_PORT);
182 
183     pci_register_bar(pci_dev, CXL_COMPONENT_REG_BAR_IDX,
184                      PCI_BASE_ADDRESS_SPACE_MEMORY |
185                          PCI_BASE_ADDRESS_MEM_TYPE_64,
186                      component_bar);
187 }
188 
189 static void cxl_rp_reset_hold(Object *obj)
190 {
191     PCIERootPortClass *rpc = PCIE_ROOT_PORT_GET_CLASS(obj);
192     CXLRootPort *crp = CXL_ROOT_PORT(obj);
193 
194     if (rpc->parent_phases.hold) {
195         rpc->parent_phases.hold(obj);
196     }
197 
198     latch_registers(crp);
199 }
200 
201 static Property gen_rp_props[] = {
202     DEFINE_PROP_UINT32("bus-reserve", CXLRootPort, res_reserve.bus, -1),
203     DEFINE_PROP_SIZE("io-reserve", CXLRootPort, res_reserve.io, -1),
204     DEFINE_PROP_SIZE("mem-reserve", CXLRootPort, res_reserve.mem_non_pref, -1),
205     DEFINE_PROP_SIZE("pref32-reserve", CXLRootPort, res_reserve.mem_pref_32,
206                      -1),
207     DEFINE_PROP_SIZE("pref64-reserve", CXLRootPort, res_reserve.mem_pref_64,
208                      -1),
209     DEFINE_PROP_END_OF_LIST()
210 };
211 
212 static void cxl_rp_dvsec_write_config(PCIDevice *dev, uint32_t addr,
213                                       uint32_t val, int len)
214 {
215     CXLRootPort *crp = CXL_ROOT_PORT(dev);
216 
217     if (range_contains(&crp->cxl_cstate.dvsecs[EXTENSIONS_PORT_DVSEC], addr)) {
218         uint8_t *reg = &dev->config[addr];
219         addr -= crp->cxl_cstate.dvsecs[EXTENSIONS_PORT_DVSEC].lob;
220         if (addr == PORT_CONTROL_OFFSET) {
221             if (pci_get_word(reg) & PORT_CONTROL_UNMASK_SBR) {
222                 /* unmask SBR */
223                 qemu_log_mask(LOG_UNIMP, "SBR mask control is not supported\n");
224             }
225             if (pci_get_word(reg) & PORT_CONTROL_ALT_MEMID_EN) {
226                 /* Alt Memory & ID Space Enable */
227                 qemu_log_mask(LOG_UNIMP,
228                               "Alt Memory & ID space is not supported\n");
229             }
230         }
231     }
232 }
233 
234 static void cxl_rp_aer_vector_update(PCIDevice *d)
235 {
236     PCIERootPortClass *rpc = PCIE_ROOT_PORT_GET_CLASS(d);
237 
238     if (rpc->aer_vector) {
239         pcie_aer_root_set_vector(d, rpc->aer_vector(d));
240     }
241 }
242 
243 static void cxl_rp_write_config(PCIDevice *d, uint32_t address, uint32_t val,
244                                 int len)
245 {
246     uint16_t slt_ctl, slt_sta;
247     uint32_t root_cmd =
248         pci_get_long(d->config + d->exp.aer_cap + PCI_ERR_ROOT_COMMAND);
249 
250     pcie_cap_slot_get(d, &slt_ctl, &slt_sta);
251     pci_bridge_write_config(d, address, val, len);
252     cxl_rp_aer_vector_update(d);
253     pcie_cap_flr_write_config(d, address, val, len);
254     pcie_cap_slot_write_config(d, slt_ctl, slt_sta, address, val, len);
255     pcie_aer_write_config(d, address, val, len);
256     pcie_aer_root_write_config(d, address, val, len, root_cmd);
257 
258     cxl_rp_dvsec_write_config(d, address, val, len);
259 }
260 
261 static void cxl_root_port_class_init(ObjectClass *oc, void *data)
262 {
263     DeviceClass *dc        = DEVICE_CLASS(oc);
264     PCIDeviceClass *k      = PCI_DEVICE_CLASS(oc);
265     ResettableClass *rc    = RESETTABLE_CLASS(oc);
266     PCIERootPortClass *rpc = PCIE_ROOT_PORT_CLASS(oc);
267 
268     k->vendor_id = PCI_VENDOR_ID_INTEL;
269     k->device_id = CXL_ROOT_PORT_DID;
270     dc->desc     = "CXL Root Port";
271     k->revision  = 0;
272     device_class_set_props(dc, gen_rp_props);
273     k->config_write = cxl_rp_write_config;
274 
275     device_class_set_parent_realize(dc, cxl_rp_realize, &rpc->parent_realize);
276     resettable_class_set_parent_phases(rc, NULL, cxl_rp_reset_hold, NULL,
277                                        &rpc->parent_phases);
278 
279     rpc->aer_offset = GEN_PCIE_ROOT_PORT_AER_OFFSET;
280     rpc->acs_offset = GEN_PCIE_ROOT_PORT_ACS_OFFSET;
281     rpc->aer_vector = cxl_rp_aer_vector;
282     rpc->interrupts_init = cxl_rp_interrupts_init;
283     rpc->interrupts_uninit = cxl_rp_interrupts_uninit;
284 
285     dc->hotpluggable = false;
286 }
287 
288 static const TypeInfo cxl_root_port_info = {
289     .name = TYPE_CXL_ROOT_PORT,
290     .parent = TYPE_PCIE_ROOT_PORT,
291     .instance_size = sizeof(CXLRootPort),
292     .class_init = cxl_root_port_class_init,
293     .interfaces = (InterfaceInfo[]) {
294         { INTERFACE_CXL_DEVICE },
295         { }
296     },
297 };
298 
299 static void cxl_register(void)
300 {
301     type_register_static(&cxl_root_port_info);
302 }
303 
304 type_init(cxl_register);
305