xref: /openbmc/qemu/hw/pci-host/xilinx-pcie.c (revision 8bca9a03)
1 /*
2  * Xilinx PCIe host controller emulation.
3  *
4  * Copyright (c) 2016 Imagination Technologies
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 "qapi/error.h"
22 #include "hw/pci/pci_bridge.h"
23 #include "hw/pci-host/xilinx-pcie.h"
24 
25 enum root_cfg_reg {
26     /* Interrupt Decode Register */
27     ROOTCFG_INTDEC              = 0x138,
28 
29     /* Interrupt Mask Register */
30     ROOTCFG_INTMASK             = 0x13c,
31     /* INTx Interrupt Received */
32 #define ROOTCFG_INTMASK_INTX    (1 << 16)
33     /* MSI Interrupt Received */
34 #define ROOTCFG_INTMASK_MSI     (1 << 17)
35 
36     /* PHY Status/Control Register */
37     ROOTCFG_PSCR                = 0x144,
38     /* Link Up */
39 #define ROOTCFG_PSCR_LINK_UP    (1 << 11)
40 
41     /* Root Port Status/Control Register */
42     ROOTCFG_RPSCR               = 0x148,
43     /* Bridge Enable */
44 #define ROOTCFG_RPSCR_BRIDGEEN  (1 << 0)
45     /* Interrupt FIFO Not Empty */
46 #define ROOTCFG_RPSCR_INTNEMPTY (1 << 18)
47     /* Interrupt FIFO Overflow */
48 #define ROOTCFG_RPSCR_INTOVF    (1 << 19)
49 
50     /* Root Port Interrupt FIFO Read Register 1 */
51     ROOTCFG_RPIFR1              = 0x158,
52 #define ROOTCFG_RPIFR1_INT_LANE_SHIFT   27
53 #define ROOTCFG_RPIFR1_INT_ASSERT_SHIFT 29
54 #define ROOTCFG_RPIFR1_INT_VALID_SHIFT  31
55     /* Root Port Interrupt FIFO Read Register 2 */
56     ROOTCFG_RPIFR2              = 0x15c,
57 };
58 
59 static void xilinx_pcie_update_intr(XilinxPCIEHost *s,
60                                     uint32_t set, uint32_t clear)
61 {
62     int level;
63 
64     s->intr |= set;
65     s->intr &= ~clear;
66 
67     if (s->intr_fifo_r != s->intr_fifo_w) {
68         s->intr |= ROOTCFG_INTMASK_INTX;
69     }
70 
71     level = !!(s->intr & s->intr_mask);
72     qemu_set_irq(s->irq, level);
73 }
74 
75 static void xilinx_pcie_queue_intr(XilinxPCIEHost *s,
76                                    uint32_t fifo_reg1, uint32_t fifo_reg2)
77 {
78     XilinxPCIEInt *intr;
79     unsigned int new_w;
80 
81     new_w = (s->intr_fifo_w + 1) % ARRAY_SIZE(s->intr_fifo);
82     if (new_w == s->intr_fifo_r) {
83         s->rpscr |= ROOTCFG_RPSCR_INTOVF;
84         return;
85     }
86 
87     intr = &s->intr_fifo[s->intr_fifo_w];
88     s->intr_fifo_w = new_w;
89 
90     intr->fifo_reg1 = fifo_reg1;
91     intr->fifo_reg2 = fifo_reg2;
92 
93     xilinx_pcie_update_intr(s, ROOTCFG_INTMASK_INTX, 0);
94 }
95 
96 static void xilinx_pcie_set_irq(void *opaque, int irq_num, int level)
97 {
98     XilinxPCIEHost *s = XILINX_PCIE_HOST(opaque);
99 
100     xilinx_pcie_queue_intr(s,
101        (irq_num << ROOTCFG_RPIFR1_INT_LANE_SHIFT) |
102            (level << ROOTCFG_RPIFR1_INT_ASSERT_SHIFT) |
103            (1 << ROOTCFG_RPIFR1_INT_VALID_SHIFT),
104        0);
105 }
106 
107 static void xilinx_pcie_host_realize(DeviceState *dev, Error **errp)
108 {
109     PCIHostState *pci = PCI_HOST_BRIDGE(dev);
110     XilinxPCIEHost *s = XILINX_PCIE_HOST(dev);
111     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
112     PCIExpressHost *pex = PCIE_HOST_BRIDGE(dev);
113 
114     snprintf(s->name, sizeof(s->name), "pcie%u", s->bus_nr);
115 
116     /* PCI configuration space */
117     pcie_host_mmcfg_init(pex, s->cfg_size);
118 
119     /* MMIO region */
120     memory_region_init(&s->mmio, OBJECT(s), "mmio", UINT64_MAX);
121     memory_region_set_enabled(&s->mmio, false);
122 
123     /* dummy PCI I/O region (not visible to the CPU) */
124     memory_region_init(&s->io, OBJECT(s), "io", 16);
125 
126     /* interrupt out */
127     qdev_init_gpio_out_named(dev, &s->irq, "interrupt_out", 1);
128 
129     sysbus_init_mmio(sbd, &pex->mmio);
130     sysbus_init_mmio(sbd, &s->mmio);
131 
132     pci->bus = pci_register_root_bus(dev, s->name, xilinx_pcie_set_irq,
133                                      pci_swizzle_map_irq_fn, s, &s->mmio,
134                                      &s->io, 0, 4, TYPE_PCIE_BUS);
135 
136     qdev_set_parent_bus(DEVICE(&s->root), BUS(pci->bus));
137     qdev_init_nofail(DEVICE(&s->root));
138 }
139 
140 static const char *xilinx_pcie_host_root_bus_path(PCIHostState *host_bridge,
141                                                   PCIBus *rootbus)
142 {
143     return "0000:00";
144 }
145 
146 static void xilinx_pcie_host_init(Object *obj)
147 {
148     XilinxPCIEHost *s = XILINX_PCIE_HOST(obj);
149     XilinxPCIERoot *root = &s->root;
150 
151     object_initialize(root, sizeof(*root), TYPE_XILINX_PCIE_ROOT);
152     object_property_add_child(obj, "root", OBJECT(root), NULL);
153     qdev_prop_set_int32(DEVICE(root), "addr", PCI_DEVFN(0, 0));
154     qdev_prop_set_bit(DEVICE(root), "multifunction", false);
155 }
156 
157 static Property xilinx_pcie_host_props[] = {
158     DEFINE_PROP_UINT32("bus_nr", XilinxPCIEHost, bus_nr, 0),
159     DEFINE_PROP_SIZE("cfg_base", XilinxPCIEHost, cfg_base, 0),
160     DEFINE_PROP_SIZE("cfg_size", XilinxPCIEHost, cfg_size, 32 << 20),
161     DEFINE_PROP_SIZE("mmio_base", XilinxPCIEHost, mmio_base, 0),
162     DEFINE_PROP_SIZE("mmio_size", XilinxPCIEHost, mmio_size, 1 << 20),
163     DEFINE_PROP_BOOL("link_up", XilinxPCIEHost, link_up, true),
164     DEFINE_PROP_END_OF_LIST(),
165 };
166 
167 static void xilinx_pcie_host_class_init(ObjectClass *klass, void *data)
168 {
169     DeviceClass *dc = DEVICE_CLASS(klass);
170     PCIHostBridgeClass *hc = PCI_HOST_BRIDGE_CLASS(klass);
171 
172     hc->root_bus_path = xilinx_pcie_host_root_bus_path;
173     dc->realize = xilinx_pcie_host_realize;
174     set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
175     dc->fw_name = "pci";
176     dc->props = xilinx_pcie_host_props;
177 }
178 
179 static const TypeInfo xilinx_pcie_host_info = {
180     .name       = TYPE_XILINX_PCIE_HOST,
181     .parent     = TYPE_PCIE_HOST_BRIDGE,
182     .instance_size = sizeof(XilinxPCIEHost),
183     .instance_init = xilinx_pcie_host_init,
184     .class_init = xilinx_pcie_host_class_init,
185 };
186 
187 static uint32_t xilinx_pcie_root_config_read(PCIDevice *d,
188                                              uint32_t address, int len)
189 {
190     XilinxPCIEHost *s = XILINX_PCIE_HOST(OBJECT(d)->parent);
191     uint32_t val;
192 
193     switch (address) {
194     case ROOTCFG_INTDEC:
195         val = s->intr;
196         break;
197     case ROOTCFG_INTMASK:
198         val = s->intr_mask;
199         break;
200     case ROOTCFG_PSCR:
201         val = s->link_up ? ROOTCFG_PSCR_LINK_UP : 0;
202         break;
203     case ROOTCFG_RPSCR:
204         if (s->intr_fifo_r != s->intr_fifo_w) {
205             s->rpscr &= ~ROOTCFG_RPSCR_INTNEMPTY;
206         } else {
207             s->rpscr |= ROOTCFG_RPSCR_INTNEMPTY;
208         }
209         val = s->rpscr;
210         break;
211     case ROOTCFG_RPIFR1:
212         if (s->intr_fifo_w == s->intr_fifo_r) {
213             /* FIFO empty */
214             val = 0;
215         } else {
216             val = s->intr_fifo[s->intr_fifo_r].fifo_reg1;
217         }
218         break;
219     case ROOTCFG_RPIFR2:
220         if (s->intr_fifo_w == s->intr_fifo_r) {
221             /* FIFO empty */
222             val = 0;
223         } else {
224             val = s->intr_fifo[s->intr_fifo_r].fifo_reg2;
225         }
226         break;
227     default:
228         val = pci_default_read_config(d, address, len);
229         break;
230     }
231     return val;
232 }
233 
234 static void xilinx_pcie_root_config_write(PCIDevice *d, uint32_t address,
235                                           uint32_t val, int len)
236 {
237     XilinxPCIEHost *s = XILINX_PCIE_HOST(OBJECT(d)->parent);
238     switch (address) {
239     case ROOTCFG_INTDEC:
240         xilinx_pcie_update_intr(s, 0, val);
241         break;
242     case ROOTCFG_INTMASK:
243         s->intr_mask = val;
244         xilinx_pcie_update_intr(s, 0, 0);
245         break;
246     case ROOTCFG_RPSCR:
247         s->rpscr &= ~ROOTCFG_RPSCR_BRIDGEEN;
248         s->rpscr |= val & ROOTCFG_RPSCR_BRIDGEEN;
249         memory_region_set_enabled(&s->mmio, val & ROOTCFG_RPSCR_BRIDGEEN);
250 
251         if (val & ROOTCFG_INTMASK_INTX) {
252             s->rpscr &= ~ROOTCFG_INTMASK_INTX;
253         }
254         break;
255     case ROOTCFG_RPIFR1:
256     case ROOTCFG_RPIFR2:
257         if (s->intr_fifo_w == s->intr_fifo_r) {
258             /* FIFO empty */
259             return;
260         } else {
261             s->intr_fifo_r = (s->intr_fifo_r + 1) % ARRAY_SIZE(s->intr_fifo);
262         }
263         break;
264     default:
265         pci_default_write_config(d, address, val, len);
266         break;
267     }
268 }
269 
270 static void xilinx_pcie_root_realize(PCIDevice *pci_dev, Error **errp)
271 {
272     BusState *bus = qdev_get_parent_bus(DEVICE(pci_dev));
273     XilinxPCIEHost *s = XILINX_PCIE_HOST(bus->parent);
274 
275     pci_set_word(pci_dev->config + PCI_COMMAND,
276                  PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
277     pci_set_word(pci_dev->config + PCI_MEMORY_BASE, s->mmio_base >> 16);
278     pci_set_word(pci_dev->config + PCI_MEMORY_LIMIT,
279                  ((s->mmio_base + s->mmio_size - 1) >> 16) & 0xfff0);
280 
281     pci_bridge_initfn(pci_dev, TYPE_PCI_BUS);
282 
283     if (pcie_endpoint_cap_v1_init(pci_dev, 0x80) < 0) {
284         error_setg(errp, "Failed to initialize PCIe capability");
285     }
286 }
287 
288 static void xilinx_pcie_root_class_init(ObjectClass *klass, void *data)
289 {
290     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
291     DeviceClass *dc = DEVICE_CLASS(klass);
292 
293     set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
294     dc->desc = "Xilinx AXI-PCIe Host Bridge";
295     k->vendor_id = PCI_VENDOR_ID_XILINX;
296     k->device_id = 0x7021;
297     k->revision = 0;
298     k->class_id = PCI_CLASS_BRIDGE_HOST;
299     k->is_bridge = true;
300     k->realize = xilinx_pcie_root_realize;
301     k->exit = pci_bridge_exitfn;
302     dc->reset = pci_bridge_reset;
303     k->config_read = xilinx_pcie_root_config_read;
304     k->config_write = xilinx_pcie_root_config_write;
305     /*
306      * PCI-facing part of the host bridge, not usable without the
307      * host-facing part, which can't be device_add'ed, yet.
308      */
309     dc->user_creatable = false;
310 }
311 
312 static const TypeInfo xilinx_pcie_root_info = {
313     .name = TYPE_XILINX_PCIE_ROOT,
314     .parent = TYPE_PCI_BRIDGE,
315     .instance_size = sizeof(XilinxPCIERoot),
316     .class_init = xilinx_pcie_root_class_init,
317     .interfaces = (InterfaceInfo[]) {
318         { INTERFACE_PCIE_DEVICE },
319         { }
320     },
321 };
322 
323 static void xilinx_pcie_register(void)
324 {
325     type_register_static(&xilinx_pcie_root_info);
326     type_register_static(&xilinx_pcie_host_info);
327 }
328 
329 type_init(xilinx_pcie_register)
330