xref: /openbmc/qemu/hw/pci-host/xilinx-pcie.c (revision f1733749)
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 "qemu/module.h"
22 #include "qemu/units.h"
23 #include "qapi/error.h"
24 #include "hw/pci/pci_bridge.h"
25 #include "hw/qdev-properties.h"
26 #include "hw/irq.h"
27 #include "hw/pci-host/xilinx-pcie.h"
28 
29 enum root_cfg_reg {
30     /* Interrupt Decode Register */
31     ROOTCFG_INTDEC              = 0x138,
32 
33     /* Interrupt Mask Register */
34     ROOTCFG_INTMASK             = 0x13c,
35     /* INTx Interrupt Received */
36 #define ROOTCFG_INTMASK_INTX    (1 << 16)
37     /* MSI Interrupt Received */
38 #define ROOTCFG_INTMASK_MSI     (1 << 17)
39 
40     /* PHY Status/Control Register */
41     ROOTCFG_PSCR                = 0x144,
42     /* Link Up */
43 #define ROOTCFG_PSCR_LINK_UP    (1 << 11)
44 
45     /* Root Port Status/Control Register */
46     ROOTCFG_RPSCR               = 0x148,
47     /* Bridge Enable */
48 #define ROOTCFG_RPSCR_BRIDGEEN  (1 << 0)
49     /* Interrupt FIFO Not Empty */
50 #define ROOTCFG_RPSCR_INTNEMPTY (1 << 18)
51     /* Interrupt FIFO Overflow */
52 #define ROOTCFG_RPSCR_INTOVF    (1 << 19)
53 
54     /* Root Port Interrupt FIFO Read Register 1 */
55     ROOTCFG_RPIFR1              = 0x158,
56 #define ROOTCFG_RPIFR1_INT_LANE_SHIFT   27
57 #define ROOTCFG_RPIFR1_INT_ASSERT_SHIFT 29
58 #define ROOTCFG_RPIFR1_INT_VALID_SHIFT  31
59     /* Root Port Interrupt FIFO Read Register 2 */
60     ROOTCFG_RPIFR2              = 0x15c,
61 };
62 
63 static void xilinx_pcie_update_intr(XilinxPCIEHost *s,
64                                     uint32_t set, uint32_t clear)
65 {
66     int level;
67 
68     s->intr |= set;
69     s->intr &= ~clear;
70 
71     if (s->intr_fifo_r != s->intr_fifo_w) {
72         s->intr |= ROOTCFG_INTMASK_INTX;
73     }
74 
75     level = !!(s->intr & s->intr_mask);
76     qemu_set_irq(s->irq, level);
77 }
78 
79 static void xilinx_pcie_queue_intr(XilinxPCIEHost *s,
80                                    uint32_t fifo_reg1, uint32_t fifo_reg2)
81 {
82     XilinxPCIEInt *intr;
83     unsigned int new_w;
84 
85     new_w = (s->intr_fifo_w + 1) % ARRAY_SIZE(s->intr_fifo);
86     if (new_w == s->intr_fifo_r) {
87         s->rpscr |= ROOTCFG_RPSCR_INTOVF;
88         return;
89     }
90 
91     intr = &s->intr_fifo[s->intr_fifo_w];
92     s->intr_fifo_w = new_w;
93 
94     intr->fifo_reg1 = fifo_reg1;
95     intr->fifo_reg2 = fifo_reg2;
96 
97     xilinx_pcie_update_intr(s, ROOTCFG_INTMASK_INTX, 0);
98 }
99 
100 static void xilinx_pcie_set_irq(void *opaque, int irq_num, int level)
101 {
102     XilinxPCIEHost *s = XILINX_PCIE_HOST(opaque);
103 
104     xilinx_pcie_queue_intr(s,
105        (irq_num << ROOTCFG_RPIFR1_INT_LANE_SHIFT) |
106            (level << ROOTCFG_RPIFR1_INT_ASSERT_SHIFT) |
107            (1 << ROOTCFG_RPIFR1_INT_VALID_SHIFT),
108        0);
109 }
110 
111 static void xilinx_pcie_host_realize(DeviceState *dev, Error **errp)
112 {
113     PCIHostState *pci = PCI_HOST_BRIDGE(dev);
114     XilinxPCIEHost *s = XILINX_PCIE_HOST(dev);
115     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
116     PCIExpressHost *pex = PCIE_HOST_BRIDGE(dev);
117 
118     snprintf(s->name, sizeof(s->name), "pcie%u", s->bus_nr);
119 
120     /* PCI configuration space */
121     pcie_host_mmcfg_init(pex, s->cfg_size);
122 
123     /* MMIO region */
124     memory_region_init(&s->mmio, OBJECT(s), "mmio", UINT64_MAX);
125     memory_region_set_enabled(&s->mmio, false);
126 
127     /* dummy PCI I/O region (not visible to the CPU) */
128     memory_region_init(&s->io, OBJECT(s), "io", 16);
129 
130     /* interrupt out */
131     qdev_init_gpio_out_named(dev, &s->irq, "interrupt_out", 1);
132 
133     sysbus_init_mmio(sbd, &pex->mmio);
134     sysbus_init_mmio(sbd, &s->mmio);
135 
136     pci->bus = pci_register_root_bus(dev, s->name, xilinx_pcie_set_irq,
137                                      pci_swizzle_map_irq_fn, s, &s->mmio,
138                                      &s->io, 0, 4, TYPE_PCIE_BUS);
139 
140     qdev_set_parent_bus(DEVICE(&s->root), BUS(pci->bus));
141     qdev_init_nofail(DEVICE(&s->root));
142 }
143 
144 static const char *xilinx_pcie_host_root_bus_path(PCIHostState *host_bridge,
145                                                   PCIBus *rootbus)
146 {
147     return "0000:00";
148 }
149 
150 static void xilinx_pcie_host_init(Object *obj)
151 {
152     XilinxPCIEHost *s = XILINX_PCIE_HOST(obj);
153     XilinxPCIERoot *root = &s->root;
154 
155     object_initialize_child(obj, "root",  root, sizeof(*root),
156                             TYPE_XILINX_PCIE_ROOT, &error_abort, NULL);
157     qdev_prop_set_int32(DEVICE(root), "addr", PCI_DEVFN(0, 0));
158     qdev_prop_set_bit(DEVICE(root), "multifunction", false);
159 }
160 
161 static Property xilinx_pcie_host_props[] = {
162     DEFINE_PROP_UINT32("bus_nr", XilinxPCIEHost, bus_nr, 0),
163     DEFINE_PROP_SIZE("cfg_base", XilinxPCIEHost, cfg_base, 0),
164     DEFINE_PROP_SIZE("cfg_size", XilinxPCIEHost, cfg_size, 32 * MiB),
165     DEFINE_PROP_SIZE("mmio_base", XilinxPCIEHost, mmio_base, 0),
166     DEFINE_PROP_SIZE("mmio_size", XilinxPCIEHost, mmio_size, 1 * MiB),
167     DEFINE_PROP_BOOL("link_up", XilinxPCIEHost, link_up, true),
168     DEFINE_PROP_END_OF_LIST(),
169 };
170 
171 static void xilinx_pcie_host_class_init(ObjectClass *klass, void *data)
172 {
173     DeviceClass *dc = DEVICE_CLASS(klass);
174     PCIHostBridgeClass *hc = PCI_HOST_BRIDGE_CLASS(klass);
175 
176     hc->root_bus_path = xilinx_pcie_host_root_bus_path;
177     dc->realize = xilinx_pcie_host_realize;
178     set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
179     dc->fw_name = "pci";
180     dc->props = xilinx_pcie_host_props;
181 }
182 
183 static const TypeInfo xilinx_pcie_host_info = {
184     .name       = TYPE_XILINX_PCIE_HOST,
185     .parent     = TYPE_PCIE_HOST_BRIDGE,
186     .instance_size = sizeof(XilinxPCIEHost),
187     .instance_init = xilinx_pcie_host_init,
188     .class_init = xilinx_pcie_host_class_init,
189 };
190 
191 static uint32_t xilinx_pcie_root_config_read(PCIDevice *d,
192                                              uint32_t address, int len)
193 {
194     XilinxPCIEHost *s = XILINX_PCIE_HOST(OBJECT(d)->parent);
195     uint32_t val;
196 
197     switch (address) {
198     case ROOTCFG_INTDEC:
199         val = s->intr;
200         break;
201     case ROOTCFG_INTMASK:
202         val = s->intr_mask;
203         break;
204     case ROOTCFG_PSCR:
205         val = s->link_up ? ROOTCFG_PSCR_LINK_UP : 0;
206         break;
207     case ROOTCFG_RPSCR:
208         if (s->intr_fifo_r != s->intr_fifo_w) {
209             s->rpscr &= ~ROOTCFG_RPSCR_INTNEMPTY;
210         } else {
211             s->rpscr |= ROOTCFG_RPSCR_INTNEMPTY;
212         }
213         val = s->rpscr;
214         break;
215     case ROOTCFG_RPIFR1:
216         if (s->intr_fifo_w == s->intr_fifo_r) {
217             /* FIFO empty */
218             val = 0;
219         } else {
220             val = s->intr_fifo[s->intr_fifo_r].fifo_reg1;
221         }
222         break;
223     case ROOTCFG_RPIFR2:
224         if (s->intr_fifo_w == s->intr_fifo_r) {
225             /* FIFO empty */
226             val = 0;
227         } else {
228             val = s->intr_fifo[s->intr_fifo_r].fifo_reg2;
229         }
230         break;
231     default:
232         val = pci_default_read_config(d, address, len);
233         break;
234     }
235     return val;
236 }
237 
238 static void xilinx_pcie_root_config_write(PCIDevice *d, uint32_t address,
239                                           uint32_t val, int len)
240 {
241     XilinxPCIEHost *s = XILINX_PCIE_HOST(OBJECT(d)->parent);
242     switch (address) {
243     case ROOTCFG_INTDEC:
244         xilinx_pcie_update_intr(s, 0, val);
245         break;
246     case ROOTCFG_INTMASK:
247         s->intr_mask = val;
248         xilinx_pcie_update_intr(s, 0, 0);
249         break;
250     case ROOTCFG_RPSCR:
251         s->rpscr &= ~ROOTCFG_RPSCR_BRIDGEEN;
252         s->rpscr |= val & ROOTCFG_RPSCR_BRIDGEEN;
253         memory_region_set_enabled(&s->mmio, val & ROOTCFG_RPSCR_BRIDGEEN);
254 
255         if (val & ROOTCFG_INTMASK_INTX) {
256             s->rpscr &= ~ROOTCFG_INTMASK_INTX;
257         }
258         break;
259     case ROOTCFG_RPIFR1:
260     case ROOTCFG_RPIFR2:
261         if (s->intr_fifo_w == s->intr_fifo_r) {
262             /* FIFO empty */
263             return;
264         } else {
265             s->intr_fifo_r = (s->intr_fifo_r + 1) % ARRAY_SIZE(s->intr_fifo);
266         }
267         break;
268     default:
269         pci_default_write_config(d, address, val, len);
270         break;
271     }
272 }
273 
274 static void xilinx_pcie_root_realize(PCIDevice *pci_dev, Error **errp)
275 {
276     BusState *bus = qdev_get_parent_bus(DEVICE(pci_dev));
277     XilinxPCIEHost *s = XILINX_PCIE_HOST(bus->parent);
278 
279     pci_set_word(pci_dev->config + PCI_COMMAND,
280                  PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
281     pci_set_word(pci_dev->config + PCI_MEMORY_BASE, s->mmio_base >> 16);
282     pci_set_word(pci_dev->config + PCI_MEMORY_LIMIT,
283                  ((s->mmio_base + s->mmio_size - 1) >> 16) & 0xfff0);
284 
285     pci_bridge_initfn(pci_dev, TYPE_PCI_BUS);
286 
287     if (pcie_endpoint_cap_v1_init(pci_dev, 0x80) < 0) {
288         error_setg(errp, "Failed to initialize PCIe capability");
289     }
290 }
291 
292 static void xilinx_pcie_root_class_init(ObjectClass *klass, void *data)
293 {
294     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
295     DeviceClass *dc = DEVICE_CLASS(klass);
296 
297     set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
298     dc->desc = "Xilinx AXI-PCIe Host Bridge";
299     k->vendor_id = PCI_VENDOR_ID_XILINX;
300     k->device_id = 0x7021;
301     k->revision = 0;
302     k->class_id = PCI_CLASS_BRIDGE_HOST;
303     k->is_bridge = true;
304     k->realize = xilinx_pcie_root_realize;
305     k->exit = pci_bridge_exitfn;
306     dc->reset = pci_bridge_reset;
307     k->config_read = xilinx_pcie_root_config_read;
308     k->config_write = xilinx_pcie_root_config_write;
309     /*
310      * PCI-facing part of the host bridge, not usable without the
311      * host-facing part, which can't be device_add'ed, yet.
312      */
313     dc->user_creatable = false;
314 }
315 
316 static const TypeInfo xilinx_pcie_root_info = {
317     .name = TYPE_XILINX_PCIE_ROOT,
318     .parent = TYPE_PCI_BRIDGE,
319     .instance_size = sizeof(XilinxPCIERoot),
320     .class_init = xilinx_pcie_root_class_init,
321     .interfaces = (InterfaceInfo[]) {
322         { INTERFACE_PCIE_DEVICE },
323         { }
324     },
325 };
326 
327 static void xilinx_pcie_register(void)
328 {
329     type_register_static(&xilinx_pcie_root_info);
330     type_register_static(&xilinx_pcie_host_info);
331 }
332 
333 type_init(xilinx_pcie_register)
334