xref: /openbmc/qemu/hw/arm/virt.c (revision b45c03f5)
1 /*
2  * ARM mach-virt emulation
3  *
4  * Copyright (c) 2013 Linaro Limited
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 it will be useful, but WITHOUT
11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13  * more details.
14  *
15  * You should have received a copy of the GNU General Public License along with
16  * this program.  If not, see <http://www.gnu.org/licenses/>.
17  *
18  * Emulate a virtual board which works by passing Linux all the information
19  * it needs about what devices are present via the device tree.
20  * There are some restrictions about what we can do here:
21  *  + we can only present devices whose Linux drivers will work based
22  *    purely on the device tree with no platform data at all
23  *  + we want to present a very stripped-down minimalist platform,
24  *    both because this reduces the security attack surface from the guest
25  *    and also because it reduces our exposure to being broken when
26  *    the kernel updates its device tree bindings and requires further
27  *    information in a device binding that we aren't providing.
28  * This is essentially the same approach kvmtool uses.
29  */
30 
31 #include "hw/sysbus.h"
32 #include "hw/arm/arm.h"
33 #include "hw/arm/primecell.h"
34 #include "hw/arm/virt.h"
35 #include "hw/devices.h"
36 #include "net/net.h"
37 #include "sysemu/block-backend.h"
38 #include "sysemu/device_tree.h"
39 #include "sysemu/sysemu.h"
40 #include "sysemu/kvm.h"
41 #include "hw/boards.h"
42 #include "hw/loader.h"
43 #include "exec/address-spaces.h"
44 #include "qemu/bitops.h"
45 #include "qemu/error-report.h"
46 #include "hw/pci-host/gpex.h"
47 #include "hw/arm/virt-acpi-build.h"
48 #include "hw/arm/sysbus-fdt.h"
49 #include "hw/platform-bus.h"
50 #include "hw/arm/fdt.h"
51 #include "hw/intc/arm_gic_common.h"
52 #include "kvm_arm.h"
53 
54 /* Number of external interrupt lines to configure the GIC with */
55 #define NUM_IRQS 256
56 
57 #define PLATFORM_BUS_NUM_IRQS 64
58 
59 static ARMPlatformBusSystemParams platform_bus_params;
60 
61 typedef struct VirtBoardInfo {
62     struct arm_boot_info bootinfo;
63     const char *cpu_model;
64     const MemMapEntry *memmap;
65     const int *irqmap;
66     int smp_cpus;
67     void *fdt;
68     int fdt_size;
69     uint32_t clock_phandle;
70     uint32_t gic_phandle;
71     uint32_t v2m_phandle;
72 } VirtBoardInfo;
73 
74 typedef struct {
75     MachineClass parent;
76     VirtBoardInfo *daughterboard;
77 } VirtMachineClass;
78 
79 typedef struct {
80     MachineState parent;
81     bool secure;
82 } VirtMachineState;
83 
84 #define TYPE_VIRT_MACHINE   "virt"
85 #define VIRT_MACHINE(obj) \
86     OBJECT_CHECK(VirtMachineState, (obj), TYPE_VIRT_MACHINE)
87 #define VIRT_MACHINE_GET_CLASS(obj) \
88     OBJECT_GET_CLASS(VirtMachineClass, obj, TYPE_VIRT_MACHINE)
89 #define VIRT_MACHINE_CLASS(klass) \
90     OBJECT_CLASS_CHECK(VirtMachineClass, klass, TYPE_VIRT_MACHINE)
91 
92 /* Addresses and sizes of our components.
93  * 0..128MB is space for a flash device so we can run bootrom code such as UEFI.
94  * 128MB..256MB is used for miscellaneous device I/O.
95  * 256MB..1GB is reserved for possible future PCI support (ie where the
96  * PCI memory window will go if we add a PCI host controller).
97  * 1GB and up is RAM (which may happily spill over into the
98  * high memory region beyond 4GB).
99  * This represents a compromise between how much RAM can be given to
100  * a 32 bit VM and leaving space for expansion and in particular for PCI.
101  * Note that devices should generally be placed at multiples of 0x10000,
102  * to accommodate guests using 64K pages.
103  */
104 static const MemMapEntry a15memmap[] = {
105     /* Space up to 0x8000000 is reserved for a boot ROM */
106     [VIRT_FLASH] =              {          0, 0x08000000 },
107     [VIRT_CPUPERIPHS] =         { 0x08000000, 0x00020000 },
108     /* GIC distributor and CPU interfaces sit inside the CPU peripheral space */
109     [VIRT_GIC_DIST] =           { 0x08000000, 0x00010000 },
110     [VIRT_GIC_CPU] =            { 0x08010000, 0x00010000 },
111     [VIRT_GIC_V2M] =            { 0x08020000, 0x00001000 },
112     [VIRT_UART] =               { 0x09000000, 0x00001000 },
113     [VIRT_RTC] =                { 0x09010000, 0x00001000 },
114     [VIRT_FW_CFG] =             { 0x09020000, 0x0000000a },
115     [VIRT_MMIO] =               { 0x0a000000, 0x00000200 },
116     /* ...repeating for a total of NUM_VIRTIO_TRANSPORTS, each of that size */
117     [VIRT_PLATFORM_BUS] =       { 0x0c000000, 0x02000000 },
118     [VIRT_PCIE_MMIO] =          { 0x10000000, 0x2eff0000 },
119     [VIRT_PCIE_PIO] =           { 0x3eff0000, 0x00010000 },
120     [VIRT_PCIE_ECAM] =          { 0x3f000000, 0x01000000 },
121     [VIRT_MEM] =                { 0x40000000, 30ULL * 1024 * 1024 * 1024 },
122 };
123 
124 static const int a15irqmap[] = {
125     [VIRT_UART] = 1,
126     [VIRT_RTC] = 2,
127     [VIRT_PCIE] = 3, /* ... to 6 */
128     [VIRT_MMIO] = 16, /* ...to 16 + NUM_VIRTIO_TRANSPORTS - 1 */
129     [VIRT_GIC_V2M] = 48, /* ...to 48 + NUM_GICV2M_SPIS - 1 */
130     [VIRT_PLATFORM_BUS] = 112, /* ...to 112 + PLATFORM_BUS_NUM_IRQS -1 */
131 };
132 
133 static VirtBoardInfo machines[] = {
134     {
135         .cpu_model = "cortex-a15",
136         .memmap = a15memmap,
137         .irqmap = a15irqmap,
138     },
139     {
140         .cpu_model = "cortex-a53",
141         .memmap = a15memmap,
142         .irqmap = a15irqmap,
143     },
144     {
145         .cpu_model = "cortex-a57",
146         .memmap = a15memmap,
147         .irqmap = a15irqmap,
148     },
149     {
150         .cpu_model = "host",
151         .memmap = a15memmap,
152         .irqmap = a15irqmap,
153     },
154 };
155 
156 static VirtBoardInfo *find_machine_info(const char *cpu)
157 {
158     int i;
159 
160     for (i = 0; i < ARRAY_SIZE(machines); i++) {
161         if (strcmp(cpu, machines[i].cpu_model) == 0) {
162             return &machines[i];
163         }
164     }
165     return NULL;
166 }
167 
168 static void create_fdt(VirtBoardInfo *vbi)
169 {
170     void *fdt = create_device_tree(&vbi->fdt_size);
171 
172     if (!fdt) {
173         error_report("create_device_tree() failed");
174         exit(1);
175     }
176 
177     vbi->fdt = fdt;
178 
179     /* Header */
180     qemu_fdt_setprop_string(fdt, "/", "compatible", "linux,dummy-virt");
181     qemu_fdt_setprop_cell(fdt, "/", "#address-cells", 0x2);
182     qemu_fdt_setprop_cell(fdt, "/", "#size-cells", 0x2);
183 
184     /*
185      * /chosen and /memory nodes must exist for load_dtb
186      * to fill in necessary properties later
187      */
188     qemu_fdt_add_subnode(fdt, "/chosen");
189     qemu_fdt_add_subnode(fdt, "/memory");
190     qemu_fdt_setprop_string(fdt, "/memory", "device_type", "memory");
191 
192     /* Clock node, for the benefit of the UART. The kernel device tree
193      * binding documentation claims the PL011 node clock properties are
194      * optional but in practice if you omit them the kernel refuses to
195      * probe for the device.
196      */
197     vbi->clock_phandle = qemu_fdt_alloc_phandle(fdt);
198     qemu_fdt_add_subnode(fdt, "/apb-pclk");
199     qemu_fdt_setprop_string(fdt, "/apb-pclk", "compatible", "fixed-clock");
200     qemu_fdt_setprop_cell(fdt, "/apb-pclk", "#clock-cells", 0x0);
201     qemu_fdt_setprop_cell(fdt, "/apb-pclk", "clock-frequency", 24000000);
202     qemu_fdt_setprop_string(fdt, "/apb-pclk", "clock-output-names",
203                                 "clk24mhz");
204     qemu_fdt_setprop_cell(fdt, "/apb-pclk", "phandle", vbi->clock_phandle);
205 
206 }
207 
208 static void fdt_add_psci_node(const VirtBoardInfo *vbi)
209 {
210     uint32_t cpu_suspend_fn;
211     uint32_t cpu_off_fn;
212     uint32_t cpu_on_fn;
213     uint32_t migrate_fn;
214     void *fdt = vbi->fdt;
215     ARMCPU *armcpu = ARM_CPU(qemu_get_cpu(0));
216 
217     qemu_fdt_add_subnode(fdt, "/psci");
218     if (armcpu->psci_version == 2) {
219         const char comp[] = "arm,psci-0.2\0arm,psci";
220         qemu_fdt_setprop(fdt, "/psci", "compatible", comp, sizeof(comp));
221 
222         cpu_off_fn = QEMU_PSCI_0_2_FN_CPU_OFF;
223         if (arm_feature(&armcpu->env, ARM_FEATURE_AARCH64)) {
224             cpu_suspend_fn = QEMU_PSCI_0_2_FN64_CPU_SUSPEND;
225             cpu_on_fn = QEMU_PSCI_0_2_FN64_CPU_ON;
226             migrate_fn = QEMU_PSCI_0_2_FN64_MIGRATE;
227         } else {
228             cpu_suspend_fn = QEMU_PSCI_0_2_FN_CPU_SUSPEND;
229             cpu_on_fn = QEMU_PSCI_0_2_FN_CPU_ON;
230             migrate_fn = QEMU_PSCI_0_2_FN_MIGRATE;
231         }
232     } else {
233         qemu_fdt_setprop_string(fdt, "/psci", "compatible", "arm,psci");
234 
235         cpu_suspend_fn = QEMU_PSCI_0_1_FN_CPU_SUSPEND;
236         cpu_off_fn = QEMU_PSCI_0_1_FN_CPU_OFF;
237         cpu_on_fn = QEMU_PSCI_0_1_FN_CPU_ON;
238         migrate_fn = QEMU_PSCI_0_1_FN_MIGRATE;
239     }
240 
241     /* We adopt the PSCI spec's nomenclature, and use 'conduit' to refer
242      * to the instruction that should be used to invoke PSCI functions.
243      * However, the device tree binding uses 'method' instead, so that is
244      * what we should use here.
245      */
246     qemu_fdt_setprop_string(fdt, "/psci", "method", "hvc");
247 
248     qemu_fdt_setprop_cell(fdt, "/psci", "cpu_suspend", cpu_suspend_fn);
249     qemu_fdt_setprop_cell(fdt, "/psci", "cpu_off", cpu_off_fn);
250     qemu_fdt_setprop_cell(fdt, "/psci", "cpu_on", cpu_on_fn);
251     qemu_fdt_setprop_cell(fdt, "/psci", "migrate", migrate_fn);
252 }
253 
254 static void fdt_add_timer_nodes(const VirtBoardInfo *vbi)
255 {
256     /* Note that on A15 h/w these interrupts are level-triggered,
257      * but for the GIC implementation provided by both QEMU and KVM
258      * they are edge-triggered.
259      */
260     ARMCPU *armcpu;
261     uint32_t irqflags = GIC_FDT_IRQ_FLAGS_EDGE_LO_HI;
262 
263     irqflags = deposit32(irqflags, GIC_FDT_IRQ_PPI_CPU_START,
264                          GIC_FDT_IRQ_PPI_CPU_WIDTH, (1 << vbi->smp_cpus) - 1);
265 
266     qemu_fdt_add_subnode(vbi->fdt, "/timer");
267 
268     armcpu = ARM_CPU(qemu_get_cpu(0));
269     if (arm_feature(&armcpu->env, ARM_FEATURE_V8)) {
270         const char compat[] = "arm,armv8-timer\0arm,armv7-timer";
271         qemu_fdt_setprop(vbi->fdt, "/timer", "compatible",
272                          compat, sizeof(compat));
273     } else {
274         qemu_fdt_setprop_string(vbi->fdt, "/timer", "compatible",
275                                 "arm,armv7-timer");
276     }
277     qemu_fdt_setprop_cells(vbi->fdt, "/timer", "interrupts",
278                        GIC_FDT_IRQ_TYPE_PPI, ARCH_TIMER_S_EL1_IRQ, irqflags,
279                        GIC_FDT_IRQ_TYPE_PPI, ARCH_TIMER_NS_EL1_IRQ, irqflags,
280                        GIC_FDT_IRQ_TYPE_PPI, ARCH_TIMER_VIRT_IRQ, irqflags,
281                        GIC_FDT_IRQ_TYPE_PPI, ARCH_TIMER_NS_EL2_IRQ, irqflags);
282 }
283 
284 static void fdt_add_cpu_nodes(const VirtBoardInfo *vbi)
285 {
286     int cpu;
287 
288     qemu_fdt_add_subnode(vbi->fdt, "/cpus");
289     qemu_fdt_setprop_cell(vbi->fdt, "/cpus", "#address-cells", 0x1);
290     qemu_fdt_setprop_cell(vbi->fdt, "/cpus", "#size-cells", 0x0);
291 
292     for (cpu = vbi->smp_cpus - 1; cpu >= 0; cpu--) {
293         char *nodename = g_strdup_printf("/cpus/cpu@%d", cpu);
294         ARMCPU *armcpu = ARM_CPU(qemu_get_cpu(cpu));
295 
296         qemu_fdt_add_subnode(vbi->fdt, nodename);
297         qemu_fdt_setprop_string(vbi->fdt, nodename, "device_type", "cpu");
298         qemu_fdt_setprop_string(vbi->fdt, nodename, "compatible",
299                                     armcpu->dtb_compatible);
300 
301         if (vbi->smp_cpus > 1) {
302             qemu_fdt_setprop_string(vbi->fdt, nodename,
303                                         "enable-method", "psci");
304         }
305 
306         qemu_fdt_setprop_cell(vbi->fdt, nodename, "reg", armcpu->mp_affinity);
307         g_free(nodename);
308     }
309 }
310 
311 static void fdt_add_v2m_gic_node(VirtBoardInfo *vbi)
312 {
313     vbi->v2m_phandle = qemu_fdt_alloc_phandle(vbi->fdt);
314     qemu_fdt_add_subnode(vbi->fdt, "/intc/v2m");
315     qemu_fdt_setprop_string(vbi->fdt, "/intc/v2m", "compatible",
316                             "arm,gic-v2m-frame");
317     qemu_fdt_setprop(vbi->fdt, "/intc/v2m", "msi-controller", NULL, 0);
318     qemu_fdt_setprop_sized_cells(vbi->fdt, "/intc/v2m", "reg",
319                                  2, vbi->memmap[VIRT_GIC_V2M].base,
320                                  2, vbi->memmap[VIRT_GIC_V2M].size);
321     qemu_fdt_setprop_cell(vbi->fdt, "/intc/v2m", "phandle", vbi->v2m_phandle);
322 }
323 
324 static void fdt_add_gic_node(VirtBoardInfo *vbi)
325 {
326     vbi->gic_phandle = qemu_fdt_alloc_phandle(vbi->fdt);
327     qemu_fdt_setprop_cell(vbi->fdt, "/", "interrupt-parent", vbi->gic_phandle);
328 
329     qemu_fdt_add_subnode(vbi->fdt, "/intc");
330     /* 'cortex-a15-gic' means 'GIC v2' */
331     qemu_fdt_setprop_string(vbi->fdt, "/intc", "compatible",
332                             "arm,cortex-a15-gic");
333     qemu_fdt_setprop_cell(vbi->fdt, "/intc", "#interrupt-cells", 3);
334     qemu_fdt_setprop(vbi->fdt, "/intc", "interrupt-controller", NULL, 0);
335     qemu_fdt_setprop_sized_cells(vbi->fdt, "/intc", "reg",
336                                      2, vbi->memmap[VIRT_GIC_DIST].base,
337                                      2, vbi->memmap[VIRT_GIC_DIST].size,
338                                      2, vbi->memmap[VIRT_GIC_CPU].base,
339                                      2, vbi->memmap[VIRT_GIC_CPU].size);
340     qemu_fdt_setprop_cell(vbi->fdt, "/intc", "#address-cells", 0x2);
341     qemu_fdt_setprop_cell(vbi->fdt, "/intc", "#size-cells", 0x2);
342     qemu_fdt_setprop(vbi->fdt, "/intc", "ranges", NULL, 0);
343     qemu_fdt_setprop_cell(vbi->fdt, "/intc", "phandle", vbi->gic_phandle);
344 }
345 
346 static void create_v2m(VirtBoardInfo *vbi, qemu_irq *pic)
347 {
348     int i;
349     int irq = vbi->irqmap[VIRT_GIC_V2M];
350     DeviceState *dev;
351 
352     dev = qdev_create(NULL, "arm-gicv2m");
353     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, vbi->memmap[VIRT_GIC_V2M].base);
354     qdev_prop_set_uint32(dev, "base-spi", irq);
355     qdev_prop_set_uint32(dev, "num-spi", NUM_GICV2M_SPIS);
356     qdev_init_nofail(dev);
357 
358     for (i = 0; i < NUM_GICV2M_SPIS; i++) {
359         sysbus_connect_irq(SYS_BUS_DEVICE(dev), i, pic[irq + i]);
360     }
361 
362     fdt_add_v2m_gic_node(vbi);
363 }
364 
365 static void create_gic(VirtBoardInfo *vbi, qemu_irq *pic)
366 {
367     /* We create a standalone GIC v2 */
368     DeviceState *gicdev;
369     SysBusDevice *gicbusdev;
370     const char *gictype;
371     int i;
372 
373     gictype = gic_class_name();
374 
375     gicdev = qdev_create(NULL, gictype);
376     qdev_prop_set_uint32(gicdev, "revision", 2);
377     qdev_prop_set_uint32(gicdev, "num-cpu", smp_cpus);
378     /* Note that the num-irq property counts both internal and external
379      * interrupts; there are always 32 of the former (mandated by GIC spec).
380      */
381     qdev_prop_set_uint32(gicdev, "num-irq", NUM_IRQS + 32);
382     qdev_init_nofail(gicdev);
383     gicbusdev = SYS_BUS_DEVICE(gicdev);
384     sysbus_mmio_map(gicbusdev, 0, vbi->memmap[VIRT_GIC_DIST].base);
385     sysbus_mmio_map(gicbusdev, 1, vbi->memmap[VIRT_GIC_CPU].base);
386 
387     /* Wire the outputs from each CPU's generic timer to the
388      * appropriate GIC PPI inputs, and the GIC's IRQ output to
389      * the CPU's IRQ input.
390      */
391     for (i = 0; i < smp_cpus; i++) {
392         DeviceState *cpudev = DEVICE(qemu_get_cpu(i));
393         int ppibase = NUM_IRQS + i * GIC_INTERNAL + GIC_NR_SGIS;
394         int irq;
395         /* Mapping from the output timer irq lines from the CPU to the
396          * GIC PPI inputs we use for the virt board.
397          */
398         const int timer_irq[] = {
399             [GTIMER_PHYS] = ARCH_TIMER_NS_EL1_IRQ,
400             [GTIMER_VIRT] = ARCH_TIMER_VIRT_IRQ,
401             [GTIMER_HYP]  = ARCH_TIMER_NS_EL2_IRQ,
402             [GTIMER_SEC]  = ARCH_TIMER_S_EL1_IRQ,
403         };
404 
405         for (irq = 0; irq < ARRAY_SIZE(timer_irq); irq++) {
406             qdev_connect_gpio_out(cpudev, irq,
407                                   qdev_get_gpio_in(gicdev,
408                                                    ppibase + timer_irq[irq]));
409         }
410 
411         sysbus_connect_irq(gicbusdev, i, qdev_get_gpio_in(cpudev, ARM_CPU_IRQ));
412         sysbus_connect_irq(gicbusdev, i + smp_cpus,
413                            qdev_get_gpio_in(cpudev, ARM_CPU_FIQ));
414     }
415 
416     for (i = 0; i < NUM_IRQS; i++) {
417         pic[i] = qdev_get_gpio_in(gicdev, i);
418     }
419 
420     fdt_add_gic_node(vbi);
421 
422     create_v2m(vbi, pic);
423 }
424 
425 static void create_uart(const VirtBoardInfo *vbi, qemu_irq *pic)
426 {
427     char *nodename;
428     hwaddr base = vbi->memmap[VIRT_UART].base;
429     hwaddr size = vbi->memmap[VIRT_UART].size;
430     int irq = vbi->irqmap[VIRT_UART];
431     const char compat[] = "arm,pl011\0arm,primecell";
432     const char clocknames[] = "uartclk\0apb_pclk";
433 
434     sysbus_create_simple("pl011", base, pic[irq]);
435 
436     nodename = g_strdup_printf("/pl011@%" PRIx64, base);
437     qemu_fdt_add_subnode(vbi->fdt, nodename);
438     /* Note that we can't use setprop_string because of the embedded NUL */
439     qemu_fdt_setprop(vbi->fdt, nodename, "compatible",
440                          compat, sizeof(compat));
441     qemu_fdt_setprop_sized_cells(vbi->fdt, nodename, "reg",
442                                      2, base, 2, size);
443     qemu_fdt_setprop_cells(vbi->fdt, nodename, "interrupts",
444                                GIC_FDT_IRQ_TYPE_SPI, irq,
445                                GIC_FDT_IRQ_FLAGS_LEVEL_HI);
446     qemu_fdt_setprop_cells(vbi->fdt, nodename, "clocks",
447                                vbi->clock_phandle, vbi->clock_phandle);
448     qemu_fdt_setprop(vbi->fdt, nodename, "clock-names",
449                          clocknames, sizeof(clocknames));
450 
451     qemu_fdt_setprop_string(vbi->fdt, "/chosen", "stdout-path", nodename);
452     g_free(nodename);
453 }
454 
455 static void create_rtc(const VirtBoardInfo *vbi, qemu_irq *pic)
456 {
457     char *nodename;
458     hwaddr base = vbi->memmap[VIRT_RTC].base;
459     hwaddr size = vbi->memmap[VIRT_RTC].size;
460     int irq = vbi->irqmap[VIRT_RTC];
461     const char compat[] = "arm,pl031\0arm,primecell";
462 
463     sysbus_create_simple("pl031", base, pic[irq]);
464 
465     nodename = g_strdup_printf("/pl031@%" PRIx64, base);
466     qemu_fdt_add_subnode(vbi->fdt, nodename);
467     qemu_fdt_setprop(vbi->fdt, nodename, "compatible", compat, sizeof(compat));
468     qemu_fdt_setprop_sized_cells(vbi->fdt, nodename, "reg",
469                                  2, base, 2, size);
470     qemu_fdt_setprop_cells(vbi->fdt, nodename, "interrupts",
471                            GIC_FDT_IRQ_TYPE_SPI, irq,
472                            GIC_FDT_IRQ_FLAGS_LEVEL_HI);
473     qemu_fdt_setprop_cell(vbi->fdt, nodename, "clocks", vbi->clock_phandle);
474     qemu_fdt_setprop_string(vbi->fdt, nodename, "clock-names", "apb_pclk");
475     g_free(nodename);
476 }
477 
478 static void create_virtio_devices(const VirtBoardInfo *vbi, qemu_irq *pic)
479 {
480     int i;
481     hwaddr size = vbi->memmap[VIRT_MMIO].size;
482 
483     /* We create the transports in forwards order. Since qbus_realize()
484      * prepends (not appends) new child buses, the incrementing loop below will
485      * create a list of virtio-mmio buses with decreasing base addresses.
486      *
487      * When a -device option is processed from the command line,
488      * qbus_find_recursive() picks the next free virtio-mmio bus in forwards
489      * order. The upshot is that -device options in increasing command line
490      * order are mapped to virtio-mmio buses with decreasing base addresses.
491      *
492      * When this code was originally written, that arrangement ensured that the
493      * guest Linux kernel would give the lowest "name" (/dev/vda, eth0, etc) to
494      * the first -device on the command line. (The end-to-end order is a
495      * function of this loop, qbus_realize(), qbus_find_recursive(), and the
496      * guest kernel's name-to-address assignment strategy.)
497      *
498      * Meanwhile, the kernel's traversal seems to have been reversed; see eg.
499      * the message, if not necessarily the code, of commit 70161ff336.
500      * Therefore the loop now establishes the inverse of the original intent.
501      *
502      * Unfortunately, we can't counteract the kernel change by reversing the
503      * loop; it would break existing command lines.
504      *
505      * In any case, the kernel makes no guarantee about the stability of
506      * enumeration order of virtio devices (as demonstrated by it changing
507      * between kernel versions). For reliable and stable identification
508      * of disks users must use UUIDs or similar mechanisms.
509      */
510     for (i = 0; i < NUM_VIRTIO_TRANSPORTS; i++) {
511         int irq = vbi->irqmap[VIRT_MMIO] + i;
512         hwaddr base = vbi->memmap[VIRT_MMIO].base + i * size;
513 
514         sysbus_create_simple("virtio-mmio", base, pic[irq]);
515     }
516 
517     /* We add dtb nodes in reverse order so that they appear in the finished
518      * device tree lowest address first.
519      *
520      * Note that this mapping is independent of the loop above. The previous
521      * loop influences virtio device to virtio transport assignment, whereas
522      * this loop controls how virtio transports are laid out in the dtb.
523      */
524     for (i = NUM_VIRTIO_TRANSPORTS - 1; i >= 0; i--) {
525         char *nodename;
526         int irq = vbi->irqmap[VIRT_MMIO] + i;
527         hwaddr base = vbi->memmap[VIRT_MMIO].base + i * size;
528 
529         nodename = g_strdup_printf("/virtio_mmio@%" PRIx64, base);
530         qemu_fdt_add_subnode(vbi->fdt, nodename);
531         qemu_fdt_setprop_string(vbi->fdt, nodename,
532                                 "compatible", "virtio,mmio");
533         qemu_fdt_setprop_sized_cells(vbi->fdt, nodename, "reg",
534                                      2, base, 2, size);
535         qemu_fdt_setprop_cells(vbi->fdt, nodename, "interrupts",
536                                GIC_FDT_IRQ_TYPE_SPI, irq,
537                                GIC_FDT_IRQ_FLAGS_EDGE_LO_HI);
538         g_free(nodename);
539     }
540 }
541 
542 static void create_one_flash(const char *name, hwaddr flashbase,
543                              hwaddr flashsize)
544 {
545     /* Create and map a single flash device. We use the same
546      * parameters as the flash devices on the Versatile Express board.
547      */
548     DriveInfo *dinfo = drive_get_next(IF_PFLASH);
549     DeviceState *dev = qdev_create(NULL, "cfi.pflash01");
550     const uint64_t sectorlength = 256 * 1024;
551 
552     if (dinfo) {
553         qdev_prop_set_drive(dev, "drive", blk_by_legacy_dinfo(dinfo),
554                             &error_abort);
555     }
556 
557     qdev_prop_set_uint32(dev, "num-blocks", flashsize / sectorlength);
558     qdev_prop_set_uint64(dev, "sector-length", sectorlength);
559     qdev_prop_set_uint8(dev, "width", 4);
560     qdev_prop_set_uint8(dev, "device-width", 2);
561     qdev_prop_set_bit(dev, "big-endian", false);
562     qdev_prop_set_uint16(dev, "id0", 0x89);
563     qdev_prop_set_uint16(dev, "id1", 0x18);
564     qdev_prop_set_uint16(dev, "id2", 0x00);
565     qdev_prop_set_uint16(dev, "id3", 0x00);
566     qdev_prop_set_string(dev, "name", name);
567     qdev_init_nofail(dev);
568 
569     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, flashbase);
570 }
571 
572 static void create_flash(const VirtBoardInfo *vbi)
573 {
574     /* Create two flash devices to fill the VIRT_FLASH space in the memmap.
575      * Any file passed via -bios goes in the first of these.
576      */
577     hwaddr flashsize = vbi->memmap[VIRT_FLASH].size / 2;
578     hwaddr flashbase = vbi->memmap[VIRT_FLASH].base;
579     char *nodename;
580 
581     if (bios_name) {
582         char *fn;
583         int image_size;
584 
585         if (drive_get(IF_PFLASH, 0, 0)) {
586             error_report("The contents of the first flash device may be "
587                          "specified with -bios or with -drive if=pflash... "
588                          "but you cannot use both options at once");
589             exit(1);
590         }
591         fn = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
592         if (!fn) {
593             error_report("Could not find ROM image '%s'", bios_name);
594             exit(1);
595         }
596         image_size = load_image_targphys(fn, flashbase, flashsize);
597         g_free(fn);
598         if (image_size < 0) {
599             error_report("Could not load ROM image '%s'", bios_name);
600             exit(1);
601         }
602     }
603 
604     create_one_flash("virt.flash0", flashbase, flashsize);
605     create_one_flash("virt.flash1", flashbase + flashsize, flashsize);
606 
607     nodename = g_strdup_printf("/flash@%" PRIx64, flashbase);
608     qemu_fdt_add_subnode(vbi->fdt, nodename);
609     qemu_fdt_setprop_string(vbi->fdt, nodename, "compatible", "cfi-flash");
610     qemu_fdt_setprop_sized_cells(vbi->fdt, nodename, "reg",
611                                  2, flashbase, 2, flashsize,
612                                  2, flashbase + flashsize, 2, flashsize);
613     qemu_fdt_setprop_cell(vbi->fdt, nodename, "bank-width", 4);
614     g_free(nodename);
615 }
616 
617 static void create_fw_cfg(const VirtBoardInfo *vbi)
618 {
619     hwaddr base = vbi->memmap[VIRT_FW_CFG].base;
620     hwaddr size = vbi->memmap[VIRT_FW_CFG].size;
621     char *nodename;
622 
623     fw_cfg_init_mem_wide(base + 8, base, 8);
624 
625     nodename = g_strdup_printf("/fw-cfg@%" PRIx64, base);
626     qemu_fdt_add_subnode(vbi->fdt, nodename);
627     qemu_fdt_setprop_string(vbi->fdt, nodename,
628                             "compatible", "qemu,fw-cfg-mmio");
629     qemu_fdt_setprop_sized_cells(vbi->fdt, nodename, "reg",
630                                  2, base, 2, size);
631     g_free(nodename);
632 }
633 
634 static void create_pcie_irq_map(const VirtBoardInfo *vbi, uint32_t gic_phandle,
635                                 int first_irq, const char *nodename)
636 {
637     int devfn, pin;
638     uint32_t full_irq_map[4 * 4 * 10] = { 0 };
639     uint32_t *irq_map = full_irq_map;
640 
641     for (devfn = 0; devfn <= 0x18; devfn += 0x8) {
642         for (pin = 0; pin < 4; pin++) {
643             int irq_type = GIC_FDT_IRQ_TYPE_SPI;
644             int irq_nr = first_irq + ((pin + PCI_SLOT(devfn)) % PCI_NUM_PINS);
645             int irq_level = GIC_FDT_IRQ_FLAGS_LEVEL_HI;
646             int i;
647 
648             uint32_t map[] = {
649                 devfn << 8, 0, 0,                           /* devfn */
650                 pin + 1,                                    /* PCI pin */
651                 gic_phandle, 0, 0, irq_type, irq_nr, irq_level }; /* GIC irq */
652 
653             /* Convert map to big endian */
654             for (i = 0; i < 10; i++) {
655                 irq_map[i] = cpu_to_be32(map[i]);
656             }
657             irq_map += 10;
658         }
659     }
660 
661     qemu_fdt_setprop(vbi->fdt, nodename, "interrupt-map",
662                      full_irq_map, sizeof(full_irq_map));
663 
664     qemu_fdt_setprop_cells(vbi->fdt, nodename, "interrupt-map-mask",
665                            0x1800, 0, 0, /* devfn (PCI_SLOT(3)) */
666                            0x7           /* PCI irq */);
667 }
668 
669 static void create_pcie(const VirtBoardInfo *vbi, qemu_irq *pic)
670 {
671     hwaddr base_mmio = vbi->memmap[VIRT_PCIE_MMIO].base;
672     hwaddr size_mmio = vbi->memmap[VIRT_PCIE_MMIO].size;
673     hwaddr base_pio = vbi->memmap[VIRT_PCIE_PIO].base;
674     hwaddr size_pio = vbi->memmap[VIRT_PCIE_PIO].size;
675     hwaddr base_ecam = vbi->memmap[VIRT_PCIE_ECAM].base;
676     hwaddr size_ecam = vbi->memmap[VIRT_PCIE_ECAM].size;
677     hwaddr base = base_mmio;
678     int nr_pcie_buses = size_ecam / PCIE_MMCFG_SIZE_MIN;
679     int irq = vbi->irqmap[VIRT_PCIE];
680     MemoryRegion *mmio_alias;
681     MemoryRegion *mmio_reg;
682     MemoryRegion *ecam_alias;
683     MemoryRegion *ecam_reg;
684     DeviceState *dev;
685     char *nodename;
686     int i;
687 
688     dev = qdev_create(NULL, TYPE_GPEX_HOST);
689     qdev_init_nofail(dev);
690 
691     /* Map only the first size_ecam bytes of ECAM space */
692     ecam_alias = g_new0(MemoryRegion, 1);
693     ecam_reg = sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 0);
694     memory_region_init_alias(ecam_alias, OBJECT(dev), "pcie-ecam",
695                              ecam_reg, 0, size_ecam);
696     memory_region_add_subregion(get_system_memory(), base_ecam, ecam_alias);
697 
698     /* Map the MMIO window into system address space so as to expose
699      * the section of PCI MMIO space which starts at the same base address
700      * (ie 1:1 mapping for that part of PCI MMIO space visible through
701      * the window).
702      */
703     mmio_alias = g_new0(MemoryRegion, 1);
704     mmio_reg = sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 1);
705     memory_region_init_alias(mmio_alias, OBJECT(dev), "pcie-mmio",
706                              mmio_reg, base_mmio, size_mmio);
707     memory_region_add_subregion(get_system_memory(), base_mmio, mmio_alias);
708 
709     /* Map IO port space */
710     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 2, base_pio);
711 
712     for (i = 0; i < GPEX_NUM_IRQS; i++) {
713         sysbus_connect_irq(SYS_BUS_DEVICE(dev), i, pic[irq + i]);
714     }
715 
716     nodename = g_strdup_printf("/pcie@%" PRIx64, base);
717     qemu_fdt_add_subnode(vbi->fdt, nodename);
718     qemu_fdt_setprop_string(vbi->fdt, nodename,
719                             "compatible", "pci-host-ecam-generic");
720     qemu_fdt_setprop_string(vbi->fdt, nodename, "device_type", "pci");
721     qemu_fdt_setprop_cell(vbi->fdt, nodename, "#address-cells", 3);
722     qemu_fdt_setprop_cell(vbi->fdt, nodename, "#size-cells", 2);
723     qemu_fdt_setprop_cells(vbi->fdt, nodename, "bus-range", 0,
724                            nr_pcie_buses - 1);
725 
726     qemu_fdt_setprop_cells(vbi->fdt, nodename, "msi-parent", vbi->v2m_phandle);
727 
728     qemu_fdt_setprop_sized_cells(vbi->fdt, nodename, "reg",
729                                  2, base_ecam, 2, size_ecam);
730     qemu_fdt_setprop_sized_cells(vbi->fdt, nodename, "ranges",
731                                  1, FDT_PCI_RANGE_IOPORT, 2, 0,
732                                  2, base_pio, 2, size_pio,
733                                  1, FDT_PCI_RANGE_MMIO, 2, base_mmio,
734                                  2, base_mmio, 2, size_mmio);
735 
736     qemu_fdt_setprop_cell(vbi->fdt, nodename, "#interrupt-cells", 1);
737     create_pcie_irq_map(vbi, vbi->gic_phandle, irq, nodename);
738 
739     g_free(nodename);
740 }
741 
742 static void create_platform_bus(VirtBoardInfo *vbi, qemu_irq *pic)
743 {
744     DeviceState *dev;
745     SysBusDevice *s;
746     int i;
747     ARMPlatformBusFDTParams *fdt_params = g_new(ARMPlatformBusFDTParams, 1);
748     MemoryRegion *sysmem = get_system_memory();
749 
750     platform_bus_params.platform_bus_base = vbi->memmap[VIRT_PLATFORM_BUS].base;
751     platform_bus_params.platform_bus_size = vbi->memmap[VIRT_PLATFORM_BUS].size;
752     platform_bus_params.platform_bus_first_irq = vbi->irqmap[VIRT_PLATFORM_BUS];
753     platform_bus_params.platform_bus_num_irqs = PLATFORM_BUS_NUM_IRQS;
754 
755     fdt_params->system_params = &platform_bus_params;
756     fdt_params->binfo = &vbi->bootinfo;
757     fdt_params->intc = "/intc";
758     /*
759      * register a machine init done notifier that creates the device tree
760      * nodes of the platform bus and its children dynamic sysbus devices
761      */
762     arm_register_platform_bus_fdt_creator(fdt_params);
763 
764     dev = qdev_create(NULL, TYPE_PLATFORM_BUS_DEVICE);
765     dev->id = TYPE_PLATFORM_BUS_DEVICE;
766     qdev_prop_set_uint32(dev, "num_irqs",
767         platform_bus_params.platform_bus_num_irqs);
768     qdev_prop_set_uint32(dev, "mmio_size",
769         platform_bus_params.platform_bus_size);
770     qdev_init_nofail(dev);
771     s = SYS_BUS_DEVICE(dev);
772 
773     for (i = 0; i < platform_bus_params.platform_bus_num_irqs; i++) {
774         int irqn = platform_bus_params.platform_bus_first_irq + i;
775         sysbus_connect_irq(s, i, pic[irqn]);
776     }
777 
778     memory_region_add_subregion(sysmem,
779                                 platform_bus_params.platform_bus_base,
780                                 sysbus_mmio_get_region(s, 0));
781 }
782 
783 static void *machvirt_dtb(const struct arm_boot_info *binfo, int *fdt_size)
784 {
785     const VirtBoardInfo *board = (const VirtBoardInfo *)binfo;
786 
787     *fdt_size = board->fdt_size;
788     return board->fdt;
789 }
790 
791 static
792 void virt_guest_info_machine_done(Notifier *notifier, void *data)
793 {
794     VirtGuestInfoState *guest_info_state = container_of(notifier,
795                                               VirtGuestInfoState, machine_done);
796     virt_acpi_setup(&guest_info_state->info);
797 }
798 
799 static void machvirt_init(MachineState *machine)
800 {
801     VirtMachineState *vms = VIRT_MACHINE(machine);
802     qemu_irq pic[NUM_IRQS];
803     MemoryRegion *sysmem = get_system_memory();
804     int n;
805     MemoryRegion *ram = g_new(MemoryRegion, 1);
806     const char *cpu_model = machine->cpu_model;
807     VirtBoardInfo *vbi;
808     VirtGuestInfoState *guest_info_state = g_malloc0(sizeof *guest_info_state);
809     VirtGuestInfo *guest_info = &guest_info_state->info;
810     char **cpustr;
811 
812     if (!cpu_model) {
813         cpu_model = "cortex-a15";
814     }
815 
816     /* Separate the actual CPU model name from any appended features */
817     cpustr = g_strsplit(cpu_model, ",", 2);
818 
819     vbi = find_machine_info(cpustr[0]);
820 
821     if (!vbi) {
822         error_report("mach-virt: CPU %s not supported", cpustr[0]);
823         exit(1);
824     }
825 
826     vbi->smp_cpus = smp_cpus;
827 
828     if (machine->ram_size > vbi->memmap[VIRT_MEM].size) {
829         error_report("mach-virt: cannot model more than 30GB RAM");
830         exit(1);
831     }
832 
833     create_fdt(vbi);
834 
835     for (n = 0; n < smp_cpus; n++) {
836         ObjectClass *oc = cpu_class_by_name(TYPE_ARM_CPU, cpustr[0]);
837         CPUClass *cc = CPU_CLASS(oc);
838         Object *cpuobj;
839         Error *err = NULL;
840         char *cpuopts = g_strdup(cpustr[1]);
841 
842         if (!oc) {
843             fprintf(stderr, "Unable to find CPU definition\n");
844             exit(1);
845         }
846         cpuobj = object_new(object_class_get_name(oc));
847 
848         /* Handle any CPU options specified by the user */
849         cc->parse_features(CPU(cpuobj), cpuopts, &err);
850         g_free(cpuopts);
851         if (err) {
852             error_report_err(err);
853             exit(1);
854         }
855 
856         if (!vms->secure) {
857             object_property_set_bool(cpuobj, false, "has_el3", NULL);
858         }
859 
860         object_property_set_int(cpuobj, QEMU_PSCI_CONDUIT_HVC, "psci-conduit",
861                                 NULL);
862 
863         /* Secondary CPUs start in PSCI powered-down state */
864         if (n > 0) {
865             object_property_set_bool(cpuobj, true, "start-powered-off", NULL);
866         }
867 
868         if (object_property_find(cpuobj, "reset-cbar", NULL)) {
869             object_property_set_int(cpuobj, vbi->memmap[VIRT_CPUPERIPHS].base,
870                                     "reset-cbar", &error_abort);
871         }
872 
873         object_property_set_bool(cpuobj, true, "realized", NULL);
874     }
875     g_strfreev(cpustr);
876     fdt_add_timer_nodes(vbi);
877     fdt_add_cpu_nodes(vbi);
878     fdt_add_psci_node(vbi);
879 
880     memory_region_allocate_system_memory(ram, NULL, "mach-virt.ram",
881                                          machine->ram_size);
882     memory_region_add_subregion(sysmem, vbi->memmap[VIRT_MEM].base, ram);
883 
884     create_flash(vbi);
885 
886     create_gic(vbi, pic);
887 
888     create_uart(vbi, pic);
889 
890     create_rtc(vbi, pic);
891 
892     create_pcie(vbi, pic);
893 
894     /* Create mmio transports, so the user can create virtio backends
895      * (which will be automatically plugged in to the transports). If
896      * no backend is created the transport will just sit harmlessly idle.
897      */
898     create_virtio_devices(vbi, pic);
899 
900     create_fw_cfg(vbi);
901     rom_set_fw(fw_cfg_find());
902 
903     guest_info->smp_cpus = smp_cpus;
904     guest_info->fw_cfg = fw_cfg_find();
905     guest_info->memmap = vbi->memmap;
906     guest_info->irqmap = vbi->irqmap;
907     guest_info_state->machine_done.notify = virt_guest_info_machine_done;
908     qemu_add_machine_init_done_notifier(&guest_info_state->machine_done);
909 
910     vbi->bootinfo.ram_size = machine->ram_size;
911     vbi->bootinfo.kernel_filename = machine->kernel_filename;
912     vbi->bootinfo.kernel_cmdline = machine->kernel_cmdline;
913     vbi->bootinfo.initrd_filename = machine->initrd_filename;
914     vbi->bootinfo.nb_cpus = smp_cpus;
915     vbi->bootinfo.board_id = -1;
916     vbi->bootinfo.loader_start = vbi->memmap[VIRT_MEM].base;
917     vbi->bootinfo.get_dtb = machvirt_dtb;
918     vbi->bootinfo.firmware_loaded = bios_name || drive_get(IF_PFLASH, 0, 0);
919     arm_load_kernel(ARM_CPU(first_cpu), &vbi->bootinfo);
920 
921     /*
922      * arm_load_kernel machine init done notifier registration must
923      * happen before the platform_bus_create call. In this latter,
924      * another notifier is registered which adds platform bus nodes.
925      * Notifiers are executed in registration reverse order.
926      */
927     create_platform_bus(vbi, pic);
928 }
929 
930 static bool virt_get_secure(Object *obj, Error **errp)
931 {
932     VirtMachineState *vms = VIRT_MACHINE(obj);
933 
934     return vms->secure;
935 }
936 
937 static void virt_set_secure(Object *obj, bool value, Error **errp)
938 {
939     VirtMachineState *vms = VIRT_MACHINE(obj);
940 
941     vms->secure = value;
942 }
943 
944 static void virt_instance_init(Object *obj)
945 {
946     VirtMachineState *vms = VIRT_MACHINE(obj);
947 
948     /* EL3 is enabled by default on virt */
949     vms->secure = true;
950     object_property_add_bool(obj, "secure", virt_get_secure,
951                              virt_set_secure, NULL);
952     object_property_set_description(obj, "secure",
953                                     "Set on/off to enable/disable the ARM "
954                                     "Security Extensions (TrustZone)",
955                                     NULL);
956 }
957 
958 static void virt_class_init(ObjectClass *oc, void *data)
959 {
960     MachineClass *mc = MACHINE_CLASS(oc);
961 
962     mc->name = TYPE_VIRT_MACHINE;
963     mc->desc = "ARM Virtual Machine",
964     mc->init = machvirt_init;
965     mc->max_cpus = 8;
966     mc->has_dynamic_sysbus = true;
967     mc->block_default_type = IF_VIRTIO;
968     mc->no_cdrom = 1;
969 }
970 
971 static const TypeInfo machvirt_info = {
972     .name = TYPE_VIRT_MACHINE,
973     .parent = TYPE_MACHINE,
974     .instance_size = sizeof(VirtMachineState),
975     .instance_init = virt_instance_init,
976     .class_size = sizeof(VirtMachineClass),
977     .class_init = virt_class_init,
978 };
979 
980 static void machvirt_machine_init(void)
981 {
982     type_register_static(&machvirt_info);
983 }
984 
985 machine_init(machvirt_machine_init);
986