xref: /qemu/hw/riscv/riscv-iommu-sys.c (revision 01c1caa9d1b4a1938e0baba1a64c26636a3aff9f)
1 /*
2  * QEMU emulation of an RISC-V IOMMU Platform Device
3  *
4  * Copyright (C) 2022-2023 Rivos Inc.
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms and conditions of the GNU General Public License,
8  * version 2 or later, as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License along
16  * with this program; if not, see <http://www.gnu.org/licenses/>.
17  */
18 
19 #include "qemu/osdep.h"
20 #include "hw/irq.h"
21 #include "hw/pci/pci_bus.h"
22 #include "hw/qdev-properties.h"
23 #include "hw/sysbus.h"
24 #include "qapi/error.h"
25 #include "qemu/error-report.h"
26 #include "qemu/host-utils.h"
27 #include "qemu/module.h"
28 #include "qom/object.h"
29 #include "exec/exec-all.h"
30 #include "trace.h"
31 
32 #include "riscv-iommu.h"
33 
34 #define RISCV_IOMMU_SYSDEV_ICVEC_VECTORS 0x3333
35 
36 #define RISCV_IOMMU_PCI_MSIX_VECTORS 5
37 
38 /* RISC-V IOMMU System Platform Device Emulation */
39 
40 struct RISCVIOMMUStateSys {
41     SysBusDevice     parent;
42     uint64_t         addr;
43     uint32_t         base_irq;
44     DeviceState      *irqchip;
45     RISCVIOMMUState  iommu;
46 
47     /* Wired int support */
48     qemu_irq         irqs[RISCV_IOMMU_INTR_COUNT];
49 
50     /* Memory Regions for MSIX table and pending bit entries. */
51     MemoryRegion msix_table_mmio;
52     MemoryRegion msix_pba_mmio;
53     uint8_t *msix_table;
54     uint8_t *msix_pba;
55 };
56 
57 static uint64_t msix_table_mmio_read(void *opaque, hwaddr addr,
58                                      unsigned size)
59 {
60     RISCVIOMMUStateSys *s = opaque;
61 
62     g_assert(addr + size <= RISCV_IOMMU_PCI_MSIX_VECTORS * PCI_MSIX_ENTRY_SIZE);
63     return pci_get_long(s->msix_table + addr);
64 }
65 
66 static void msix_table_mmio_write(void *opaque, hwaddr addr,
67                                   uint64_t val, unsigned size)
68 {
69     RISCVIOMMUStateSys *s = opaque;
70 
71     g_assert(addr + size <= RISCV_IOMMU_PCI_MSIX_VECTORS * PCI_MSIX_ENTRY_SIZE);
72     pci_set_long(s->msix_table + addr, val);
73 }
74 
75 static const MemoryRegionOps msix_table_mmio_ops = {
76     .read = msix_table_mmio_read,
77     .write = msix_table_mmio_write,
78     .endianness = DEVICE_LITTLE_ENDIAN,
79     .valid = {
80         .min_access_size = 4,
81         .max_access_size = 8,
82     },
83     .impl = {
84         .max_access_size = 4,
85     },
86 };
87 
88 static uint64_t msix_pba_mmio_read(void *opaque, hwaddr addr,
89                                    unsigned size)
90 {
91     RISCVIOMMUStateSys *s = opaque;
92 
93     return pci_get_long(s->msix_pba + addr);
94 }
95 
96 static void msix_pba_mmio_write(void *opaque, hwaddr addr,
97                                 uint64_t val, unsigned size)
98 {
99 }
100 
101 static const MemoryRegionOps msix_pba_mmio_ops = {
102     .read = msix_pba_mmio_read,
103     .write = msix_pba_mmio_write,
104     .endianness = DEVICE_LITTLE_ENDIAN,
105     .valid = {
106         .min_access_size = 4,
107         .max_access_size = 8,
108     },
109     .impl = {
110         .max_access_size = 4,
111     },
112 };
113 
114 static void riscv_iommu_sysdev_init_msi(RISCVIOMMUStateSys *s,
115                                         uint32_t n_vectors)
116 {
117     RISCVIOMMUState *iommu = &s->iommu;
118     uint32_t table_size = table_size = n_vectors * PCI_MSIX_ENTRY_SIZE;
119     uint32_t table_offset = RISCV_IOMMU_REG_MSI_CONFIG;
120     uint32_t pba_size = QEMU_ALIGN_UP(n_vectors, 64) / 8;
121     uint32_t pba_offset = RISCV_IOMMU_REG_MSI_CONFIG + 256;
122 
123     s->msix_table = g_malloc0(table_size);
124     s->msix_pba = g_malloc0(pba_size);
125 
126     memory_region_init_io(&s->msix_table_mmio, OBJECT(s), &msix_table_mmio_ops,
127                           s, "msix-table", table_size);
128     memory_region_add_subregion(&iommu->regs_mr, table_offset,
129                                 &s->msix_table_mmio);
130 
131     memory_region_init_io(&s->msix_pba_mmio, OBJECT(s), &msix_pba_mmio_ops, s,
132                           "msix-pba", pba_size);
133     memory_region_add_subregion(&iommu->regs_mr, pba_offset,
134                                 &s->msix_pba_mmio);
135 }
136 
137 static void riscv_iommu_sysdev_send_MSI(RISCVIOMMUStateSys *s,
138                                         uint32_t vector)
139 {
140     uint8_t *table_entry = s->msix_table + vector * PCI_MSIX_ENTRY_SIZE;
141     uint64_t msi_addr = pci_get_quad(table_entry + PCI_MSIX_ENTRY_LOWER_ADDR);
142     uint32_t msi_data = pci_get_long(table_entry + PCI_MSIX_ENTRY_DATA);
143     MemTxResult result;
144 
145     address_space_stl_le(&address_space_memory, msi_addr,
146                          msi_data, MEMTXATTRS_UNSPECIFIED, &result);
147     trace_riscv_iommu_sys_msi_sent(vector, msi_addr, msi_data, result);
148 }
149 
150 static void riscv_iommu_sysdev_notify(RISCVIOMMUState *iommu,
151                                       unsigned vector)
152 {
153     RISCVIOMMUStateSys *s = container_of(iommu, RISCVIOMMUStateSys, iommu);
154     uint32_t fctl =  riscv_iommu_reg_get32(iommu, RISCV_IOMMU_REG_FCTL);
155 
156     if (fctl & RISCV_IOMMU_FCTL_WSI) {
157         qemu_irq_pulse(s->irqs[vector]);
158         trace_riscv_iommu_sys_irq_sent(vector);
159         return;
160     }
161 
162     riscv_iommu_sysdev_send_MSI(s, vector);
163 }
164 
165 static void riscv_iommu_sys_realize(DeviceState *dev, Error **errp)
166 {
167     RISCVIOMMUStateSys *s = RISCV_IOMMU_SYS(dev);
168     SysBusDevice *sysdev = SYS_BUS_DEVICE(s);
169     PCIBus *pci_bus;
170     qemu_irq irq;
171 
172     qdev_realize(DEVICE(&s->iommu), NULL, errp);
173     sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->iommu.regs_mr);
174     if (s->addr) {
175         sysbus_mmio_map(SYS_BUS_DEVICE(s), 0, s->addr);
176     }
177 
178     pci_bus = (PCIBus *) object_resolve_path_type("", TYPE_PCI_BUS, NULL);
179     if (pci_bus) {
180         riscv_iommu_pci_setup_iommu(&s->iommu, pci_bus, errp);
181     }
182 
183     s->iommu.notify = riscv_iommu_sysdev_notify;
184 
185     /* 4 IRQs are defined starting from s->base_irq */
186     for (int i = 0; i < RISCV_IOMMU_INTR_COUNT; i++) {
187         sysbus_init_irq(sysdev, &s->irqs[i]);
188         irq = qdev_get_gpio_in(s->irqchip, s->base_irq + i);
189         sysbus_connect_irq(sysdev, i, irq);
190     }
191 
192     riscv_iommu_sysdev_init_msi(s, RISCV_IOMMU_PCI_MSIX_VECTORS);
193 }
194 
195 static void riscv_iommu_sys_init(Object *obj)
196 {
197     RISCVIOMMUStateSys *s = RISCV_IOMMU_SYS(obj);
198     RISCVIOMMUState *iommu = &s->iommu;
199 
200     object_initialize_child(obj, "iommu", iommu, TYPE_RISCV_IOMMU);
201     qdev_alias_all_properties(DEVICE(iommu), obj);
202 
203     iommu->icvec_avail_vectors = RISCV_IOMMU_SYSDEV_ICVEC_VECTORS;
204     riscv_iommu_set_cap_igs(iommu, RISCV_IOMMU_CAP_IGS_BOTH);
205 }
206 
207 static Property riscv_iommu_sys_properties[] = {
208     DEFINE_PROP_UINT64("addr", RISCVIOMMUStateSys, addr, 0),
209     DEFINE_PROP_UINT32("base-irq", RISCVIOMMUStateSys, base_irq, 0),
210     DEFINE_PROP_LINK("irqchip", RISCVIOMMUStateSys, irqchip,
211                      TYPE_DEVICE, DeviceState *),
212     DEFINE_PROP_END_OF_LIST(),
213 };
214 
215 static void riscv_iommu_sys_class_init(ObjectClass *klass, void *data)
216 {
217     DeviceClass *dc = DEVICE_CLASS(klass);
218     dc->realize = riscv_iommu_sys_realize;
219     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
220     device_class_set_props(dc, riscv_iommu_sys_properties);
221 }
222 
223 static const TypeInfo riscv_iommu_sys = {
224     .name          = TYPE_RISCV_IOMMU_SYS,
225     .parent        = TYPE_SYS_BUS_DEVICE,
226     .class_init    = riscv_iommu_sys_class_init,
227     .instance_init = riscv_iommu_sys_init,
228     .instance_size = sizeof(RISCVIOMMUStateSys),
229 };
230 
231 static void riscv_iommu_register_sys(void)
232 {
233     type_register_static(&riscv_iommu_sys);
234 }
235 
236 type_init(riscv_iommu_register_sys)
237