/* * ARM mach-virt emulation * * Copyright (c) 2013 Linaro Limited * * This program is free software; you can redistribute it and/or modify it * under the terms and conditions of the GNU General Public License, * version 2 or later, as published by the Free Software Foundation. * * This program is distributed in the hope it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. * * You should have received a copy of the GNU General Public License along with * this program. If not, see . * * Emulate a virtual board which works by passing Linux all the information * it needs about what devices are present via the device tree. * There are some restrictions about what we can do here: * + we can only present devices whose Linux drivers will work based * purely on the device tree with no platform data at all * + we want to present a very stripped-down minimalist platform, * both because this reduces the security attack surface from the guest * and also because it reduces our exposure to being broken when * the kernel updates its device tree bindings and requires further * information in a device binding that we aren't providing. * This is essentially the same approach kvmtool uses. */ #include "hw/sysbus.h" #include "hw/arm/arm.h" #include "hw/arm/primecell.h" #include "hw/devices.h" #include "net/net.h" #include "sysemu/device_tree.h" #include "sysemu/sysemu.h" #include "sysemu/kvm.h" #include "hw/boards.h" #include "exec/address-spaces.h" #include "qemu/bitops.h" #include "qemu/error-report.h" #define NUM_VIRTIO_TRANSPORTS 32 /* Number of external interrupt lines to configure the GIC with */ #define NUM_IRQS 128 #define GIC_FDT_IRQ_TYPE_SPI 0 #define GIC_FDT_IRQ_TYPE_PPI 1 #define GIC_FDT_IRQ_FLAGS_EDGE_LO_HI 1 #define GIC_FDT_IRQ_FLAGS_EDGE_HI_LO 2 #define GIC_FDT_IRQ_FLAGS_LEVEL_HI 4 #define GIC_FDT_IRQ_FLAGS_LEVEL_LO 8 #define GIC_FDT_IRQ_PPI_CPU_START 8 #define GIC_FDT_IRQ_PPI_CPU_WIDTH 8 enum { VIRT_FLASH, VIRT_MEM, VIRT_CPUPERIPHS, VIRT_GIC_DIST, VIRT_GIC_CPU, VIRT_UART, VIRT_MMIO, VIRT_RTC, }; typedef struct MemMapEntry { hwaddr base; hwaddr size; } MemMapEntry; typedef struct VirtBoardInfo { struct arm_boot_info bootinfo; const char *cpu_model; const MemMapEntry *memmap; const int *irqmap; int smp_cpus; void *fdt; int fdt_size; uint32_t clock_phandle; } VirtBoardInfo; /* Addresses and sizes of our components. * 0..128MB is space for a flash device so we can run bootrom code such as UEFI. * 128MB..256MB is used for miscellaneous device I/O. * 256MB..1GB is reserved for possible future PCI support (ie where the * PCI memory window will go if we add a PCI host controller). * 1GB and up is RAM (which may happily spill over into the * high memory region beyond 4GB). * This represents a compromise between how much RAM can be given to * a 32 bit VM and leaving space for expansion and in particular for PCI. * Note that devices should generally be placed at multiples of 0x10000, * to accommodate guests using 64K pages. */ static const MemMapEntry a15memmap[] = { /* Space up to 0x8000000 is reserved for a boot ROM */ [VIRT_FLASH] = { 0, 0x08000000 }, [VIRT_CPUPERIPHS] = { 0x08000000, 0x00020000 }, /* GIC distributor and CPU interfaces sit inside the CPU peripheral space */ [VIRT_GIC_DIST] = { 0x08000000, 0x00010000 }, [VIRT_GIC_CPU] = { 0x08010000, 0x00010000 }, [VIRT_UART] = { 0x09000000, 0x00001000 }, [VIRT_RTC] = { 0x09010000, 0x00001000 }, [VIRT_MMIO] = { 0x0a000000, 0x00000200 }, /* ...repeating for a total of NUM_VIRTIO_TRANSPORTS, each of that size */ /* 0x10000000 .. 0x40000000 reserved for PCI */ [VIRT_MEM] = { 0x40000000, 30ULL * 1024 * 1024 * 1024 }, }; static const int a15irqmap[] = { [VIRT_UART] = 1, [VIRT_RTC] = 2, [VIRT_MMIO] = 16, /* ...to 16 + NUM_VIRTIO_TRANSPORTS - 1 */ }; static VirtBoardInfo machines[] = { { .cpu_model = "cortex-a15", .memmap = a15memmap, .irqmap = a15irqmap, }, { .cpu_model = "cortex-a57", .memmap = a15memmap, .irqmap = a15irqmap, }, { .cpu_model = "host", .memmap = a15memmap, .irqmap = a15irqmap, }, }; static VirtBoardInfo *find_machine_info(const char *cpu) { int i; for (i = 0; i < ARRAY_SIZE(machines); i++) { if (strcmp(cpu, machines[i].cpu_model) == 0) { return &machines[i]; } } return NULL; } static void create_fdt(VirtBoardInfo *vbi) { void *fdt = create_device_tree(&vbi->fdt_size); if (!fdt) { error_report("create_device_tree() failed"); exit(1); } vbi->fdt = fdt; /* Header */ qemu_fdt_setprop_string(fdt, "/", "compatible", "linux,dummy-virt"); qemu_fdt_setprop_cell(fdt, "/", "#address-cells", 0x2); qemu_fdt_setprop_cell(fdt, "/", "#size-cells", 0x2); /* * /chosen and /memory nodes must exist for load_dtb * to fill in necessary properties later */ qemu_fdt_add_subnode(fdt, "/chosen"); qemu_fdt_add_subnode(fdt, "/memory"); qemu_fdt_setprop_string(fdt, "/memory", "device_type", "memory"); /* Clock node, for the benefit of the UART. The kernel device tree * binding documentation claims the PL011 node clock properties are * optional but in practice if you omit them the kernel refuses to * probe for the device. */ vbi->clock_phandle = qemu_fdt_alloc_phandle(fdt); qemu_fdt_add_subnode(fdt, "/apb-pclk"); qemu_fdt_setprop_string(fdt, "/apb-pclk", "compatible", "fixed-clock"); qemu_fdt_setprop_cell(fdt, "/apb-pclk", "#clock-cells", 0x0); qemu_fdt_setprop_cell(fdt, "/apb-pclk", "clock-frequency", 24000000); qemu_fdt_setprop_string(fdt, "/apb-pclk", "clock-output-names", "clk24mhz"); qemu_fdt_setprop_cell(fdt, "/apb-pclk", "phandle", vbi->clock_phandle); } static void fdt_add_psci_node(const VirtBoardInfo *vbi) { void *fdt = vbi->fdt; ARMCPU *armcpu = ARM_CPU(qemu_get_cpu(0)); /* No PSCI for TCG yet */ if (kvm_enabled()) { uint32_t cpu_suspend_fn; uint32_t cpu_off_fn; uint32_t cpu_on_fn; uint32_t migrate_fn; qemu_fdt_add_subnode(fdt, "/psci"); if (armcpu->psci_version == 2) { const char comp[] = "arm,psci-0.2\0arm,psci"; qemu_fdt_setprop(fdt, "/psci", "compatible", comp, sizeof(comp)); cpu_off_fn = QEMU_PSCI_0_2_FN_CPU_OFF; if (arm_feature(&armcpu->env, ARM_FEATURE_AARCH64)) { cpu_suspend_fn = QEMU_PSCI_0_2_FN64_CPU_SUSPEND; cpu_on_fn = QEMU_PSCI_0_2_FN64_CPU_ON; migrate_fn = QEMU_PSCI_0_2_FN64_MIGRATE; } else { cpu_suspend_fn = QEMU_PSCI_0_2_FN_CPU_SUSPEND; cpu_on_fn = QEMU_PSCI_0_2_FN_CPU_ON; migrate_fn = QEMU_PSCI_0_2_FN_MIGRATE; } } else { qemu_fdt_setprop_string(fdt, "/psci", "compatible", "arm,psci"); cpu_suspend_fn = QEMU_PSCI_0_1_FN_CPU_SUSPEND; cpu_off_fn = QEMU_PSCI_0_1_FN_CPU_OFF; cpu_on_fn = QEMU_PSCI_0_1_FN_CPU_ON; migrate_fn = QEMU_PSCI_0_1_FN_MIGRATE; } qemu_fdt_setprop_string(fdt, "/psci", "method", "hvc"); qemu_fdt_setprop_cell(fdt, "/psci", "cpu_suspend", cpu_suspend_fn); qemu_fdt_setprop_cell(fdt, "/psci", "cpu_off", cpu_off_fn); qemu_fdt_setprop_cell(fdt, "/psci", "cpu_on", cpu_on_fn); qemu_fdt_setprop_cell(fdt, "/psci", "migrate", migrate_fn); } } static void fdt_add_timer_nodes(const VirtBoardInfo *vbi) { /* Note that on A15 h/w these interrupts are level-triggered, * but for the GIC implementation provided by both QEMU and KVM * they are edge-triggered. */ uint32_t irqflags = GIC_FDT_IRQ_FLAGS_EDGE_LO_HI; irqflags = deposit32(irqflags, GIC_FDT_IRQ_PPI_CPU_START, GIC_FDT_IRQ_PPI_CPU_WIDTH, (1 << vbi->smp_cpus) - 1); qemu_fdt_add_subnode(vbi->fdt, "/timer"); qemu_fdt_setprop_string(vbi->fdt, "/timer", "compatible", "arm,armv7-timer"); qemu_fdt_setprop_cells(vbi->fdt, "/timer", "interrupts", GIC_FDT_IRQ_TYPE_PPI, 13, irqflags, GIC_FDT_IRQ_TYPE_PPI, 14, irqflags, GIC_FDT_IRQ_TYPE_PPI, 11, irqflags, GIC_FDT_IRQ_TYPE_PPI, 10, irqflags); } static void fdt_add_cpu_nodes(const VirtBoardInfo *vbi) { int cpu; qemu_fdt_add_subnode(vbi->fdt, "/cpus"); qemu_fdt_setprop_cell(vbi->fdt, "/cpus", "#address-cells", 0x1); qemu_fdt_setprop_cell(vbi->fdt, "/cpus", "#size-cells", 0x0); for (cpu = vbi->smp_cpus - 1; cpu >= 0; cpu--) { char *nodename = g_strdup_printf("/cpus/cpu@%d", cpu); ARMCPU *armcpu = ARM_CPU(qemu_get_cpu(cpu)); qemu_fdt_add_subnode(vbi->fdt, nodename); qemu_fdt_setprop_string(vbi->fdt, nodename, "device_type", "cpu"); qemu_fdt_setprop_string(vbi->fdt, nodename, "compatible", armcpu->dtb_compatible); if (vbi->smp_cpus > 1) { qemu_fdt_setprop_string(vbi->fdt, nodename, "enable-method", "psci"); } qemu_fdt_setprop_cell(vbi->fdt, nodename, "reg", cpu); g_free(nodename); } } static void fdt_add_gic_node(const VirtBoardInfo *vbi) { uint32_t gic_phandle; gic_phandle = qemu_fdt_alloc_phandle(vbi->fdt); qemu_fdt_setprop_cell(vbi->fdt, "/", "interrupt-parent", gic_phandle); qemu_fdt_add_subnode(vbi->fdt, "/intc"); /* 'cortex-a15-gic' means 'GIC v2' */ qemu_fdt_setprop_string(vbi->fdt, "/intc", "compatible", "arm,cortex-a15-gic"); qemu_fdt_setprop_cell(vbi->fdt, "/intc", "#interrupt-cells", 3); qemu_fdt_setprop(vbi->fdt, "/intc", "interrupt-controller", NULL, 0); qemu_fdt_setprop_sized_cells(vbi->fdt, "/intc", "reg", 2, vbi->memmap[VIRT_GIC_DIST].base, 2, vbi->memmap[VIRT_GIC_DIST].size, 2, vbi->memmap[VIRT_GIC_CPU].base, 2, vbi->memmap[VIRT_GIC_CPU].size); qemu_fdt_setprop_cell(vbi->fdt, "/intc", "phandle", gic_phandle); } static void create_gic(const VirtBoardInfo *vbi, qemu_irq *pic) { /* We create a standalone GIC v2 */ DeviceState *gicdev; SysBusDevice *gicbusdev; const char *gictype = "arm_gic"; int i; if (kvm_irqchip_in_kernel()) { gictype = "kvm-arm-gic"; } gicdev = qdev_create(NULL, gictype); qdev_prop_set_uint32(gicdev, "revision", 2); qdev_prop_set_uint32(gicdev, "num-cpu", smp_cpus); /* Note that the num-irq property counts both internal and external * interrupts; there are always 32 of the former (mandated by GIC spec). */ qdev_prop_set_uint32(gicdev, "num-irq", NUM_IRQS + 32); qdev_init_nofail(gicdev); gicbusdev = SYS_BUS_DEVICE(gicdev); sysbus_mmio_map(gicbusdev, 0, vbi->memmap[VIRT_GIC_DIST].base); sysbus_mmio_map(gicbusdev, 1, vbi->memmap[VIRT_GIC_CPU].base); /* Wire the outputs from each CPU's generic timer to the * appropriate GIC PPI inputs, and the GIC's IRQ output to * the CPU's IRQ input. */ for (i = 0; i < smp_cpus; i++) { DeviceState *cpudev = DEVICE(qemu_get_cpu(i)); int ppibase = NUM_IRQS + i * 32; /* physical timer; we wire it up to the non-secure timer's ID, * since a real A15 always has TrustZone but QEMU doesn't. */ qdev_connect_gpio_out(cpudev, 0, qdev_get_gpio_in(gicdev, ppibase + 30)); /* virtual timer */ qdev_connect_gpio_out(cpudev, 1, qdev_get_gpio_in(gicdev, ppibase + 27)); sysbus_connect_irq(gicbusdev, i, qdev_get_gpio_in(cpudev, ARM_CPU_IRQ)); } for (i = 0; i < NUM_IRQS; i++) { pic[i] = qdev_get_gpio_in(gicdev, i); } fdt_add_gic_node(vbi); } static void create_uart(const VirtBoardInfo *vbi, qemu_irq *pic) { char *nodename; hwaddr base = vbi->memmap[VIRT_UART].base; hwaddr size = vbi->memmap[VIRT_UART].size; int irq = vbi->irqmap[VIRT_UART]; const char compat[] = "arm,pl011\0arm,primecell"; const char clocknames[] = "uartclk\0apb_pclk"; sysbus_create_simple("pl011", base, pic[irq]); nodename = g_strdup_printf("/pl011@%" PRIx64, base); qemu_fdt_add_subnode(vbi->fdt, nodename); /* Note that we can't use setprop_string because of the embedded NUL */ qemu_fdt_setprop(vbi->fdt, nodename, "compatible", compat, sizeof(compat)); qemu_fdt_setprop_sized_cells(vbi->fdt, nodename, "reg", 2, base, 2, size); qemu_fdt_setprop_cells(vbi->fdt, nodename, "interrupts", GIC_FDT_IRQ_TYPE_SPI, irq, GIC_FDT_IRQ_FLAGS_EDGE_LO_HI); qemu_fdt_setprop_cells(vbi->fdt, nodename, "clocks", vbi->clock_phandle, vbi->clock_phandle); qemu_fdt_setprop(vbi->fdt, nodename, "clock-names", clocknames, sizeof(clocknames)); g_free(nodename); } static void create_rtc(const VirtBoardInfo *vbi, qemu_irq *pic) { char *nodename; hwaddr base = vbi->memmap[VIRT_RTC].base; hwaddr size = vbi->memmap[VIRT_RTC].size; int irq = vbi->irqmap[VIRT_RTC]; const char compat[] = "arm,pl031\0arm,primecell"; sysbus_create_simple("pl031", base, pic[irq]); nodename = g_strdup_printf("/pl031@%" PRIx64, base); qemu_fdt_add_subnode(vbi->fdt, nodename); qemu_fdt_setprop(vbi->fdt, nodename, "compatible", compat, sizeof(compat)); qemu_fdt_setprop_sized_cells(vbi->fdt, nodename, "reg", 2, base, 2, size); qemu_fdt_setprop_cells(vbi->fdt, nodename, "interrupts", GIC_FDT_IRQ_TYPE_SPI, irq, GIC_FDT_IRQ_FLAGS_EDGE_LO_HI); qemu_fdt_setprop_cell(vbi->fdt, nodename, "clocks", vbi->clock_phandle); qemu_fdt_setprop_string(vbi->fdt, nodename, "clock-names", "apb_pclk"); g_free(nodename); } static void create_virtio_devices(const VirtBoardInfo *vbi, qemu_irq *pic) { int i; hwaddr size = vbi->memmap[VIRT_MMIO].size; /* Note that we have to create the transports in forwards order * so that command line devices are inserted lowest address first, * and then add dtb nodes in reverse order so that they appear in * the finished device tree lowest address first. */ for (i = 0; i < NUM_VIRTIO_TRANSPORTS; i++) { int irq = vbi->irqmap[VIRT_MMIO] + i; hwaddr base = vbi->memmap[VIRT_MMIO].base + i * size; sysbus_create_simple("virtio-mmio", base, pic[irq]); } for (i = NUM_VIRTIO_TRANSPORTS - 1; i >= 0; i--) { char *nodename; int irq = vbi->irqmap[VIRT_MMIO] + i; hwaddr base = vbi->memmap[VIRT_MMIO].base + i * size; nodename = g_strdup_printf("/virtio_mmio@%" PRIx64, base); qemu_fdt_add_subnode(vbi->fdt, nodename); qemu_fdt_setprop_string(vbi->fdt, nodename, "compatible", "virtio,mmio"); qemu_fdt_setprop_sized_cells(vbi->fdt, nodename, "reg", 2, base, 2, size); qemu_fdt_setprop_cells(vbi->fdt, nodename, "interrupts", GIC_FDT_IRQ_TYPE_SPI, irq, GIC_FDT_IRQ_FLAGS_EDGE_LO_HI); g_free(nodename); } } static void *machvirt_dtb(const struct arm_boot_info *binfo, int *fdt_size) { const VirtBoardInfo *board = (const VirtBoardInfo *)binfo; *fdt_size = board->fdt_size; return board->fdt; } static void machvirt_init(MachineState *machine) { qemu_irq pic[NUM_IRQS]; MemoryRegion *sysmem = get_system_memory(); int n; MemoryRegion *ram = g_new(MemoryRegion, 1); const char *cpu_model = machine->cpu_model; VirtBoardInfo *vbi; if (!cpu_model) { cpu_model = "cortex-a15"; } vbi = find_machine_info(cpu_model); if (!vbi) { error_report("mach-virt: CPU %s not supported", cpu_model); exit(1); } vbi->smp_cpus = smp_cpus; /* * Only supported method of starting secondary CPUs is PSCI and * PSCI is not yet supported with TCG, so limit smp_cpus to 1 * if we're not using KVM. */ if (!kvm_enabled() && smp_cpus > 1) { error_report("mach-virt: must enable KVM to use multiple CPUs"); exit(1); } if (machine->ram_size > vbi->memmap[VIRT_MEM].size) { error_report("mach-virt: cannot model more than 30GB RAM"); exit(1); } create_fdt(vbi); fdt_add_timer_nodes(vbi); for (n = 0; n < smp_cpus; n++) { ObjectClass *oc = cpu_class_by_name(TYPE_ARM_CPU, cpu_model); Object *cpuobj; if (!oc) { fprintf(stderr, "Unable to find CPU definition\n"); exit(1); } cpuobj = object_new(object_class_get_name(oc)); /* Secondary CPUs start in PSCI powered-down state */ if (n > 0) { object_property_set_bool(cpuobj, true, "start-powered-off", NULL); } if (object_property_find(cpuobj, "reset-cbar", NULL)) { object_property_set_int(cpuobj, vbi->memmap[VIRT_CPUPERIPHS].base, "reset-cbar", &error_abort); } object_property_set_bool(cpuobj, true, "realized", NULL); } fdt_add_cpu_nodes(vbi); fdt_add_psci_node(vbi); memory_region_init_ram(ram, NULL, "mach-virt.ram", machine->ram_size, &error_abort); vmstate_register_ram_global(ram); memory_region_add_subregion(sysmem, vbi->memmap[VIRT_MEM].base, ram); create_gic(vbi, pic); create_uart(vbi, pic); create_rtc(vbi, pic); /* Create mmio transports, so the user can create virtio backends * (which will be automatically plugged in to the transports). If * no backend is created the transport will just sit harmlessly idle. */ create_virtio_devices(vbi, pic); vbi->bootinfo.ram_size = machine->ram_size; vbi->bootinfo.kernel_filename = machine->kernel_filename; vbi->bootinfo.kernel_cmdline = machine->kernel_cmdline; vbi->bootinfo.initrd_filename = machine->initrd_filename; vbi->bootinfo.nb_cpus = smp_cpus; vbi->bootinfo.board_id = -1; vbi->bootinfo.loader_start = vbi->memmap[VIRT_MEM].base; vbi->bootinfo.get_dtb = machvirt_dtb; arm_load_kernel(ARM_CPU(first_cpu), &vbi->bootinfo); } static QEMUMachine machvirt_a15_machine = { .name = "virt", .desc = "ARM Virtual Machine", .init = machvirt_init, .max_cpus = 8, }; static void machvirt_machine_init(void) { qemu_register_machine(&machvirt_a15_machine); } machine_init(machvirt_machine_init);