From f5fdcd6e58ec35b4463569694fc15d28c505c4d0 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Fri, 22 Nov 2013 17:17:14 +0000 Subject: hw/arm: Add 'virt' platform Add 'virt' platform support corresponding to arch/arm/mach-virt in the Linux kernel tree. This has no platform-specific code but can use any device whose kernel driver is is able to work purely from a device tree node. We use this to instantiate a minimal set of devices: a GIC and some virtio-mmio transports. Signed-off-by: John Rigby Reviewed-by: Christoffer Dall Message-id: 1385140638-10444-8-git-send-email-peter.maydell@linaro.org [PMM: Significantly overhauled: * renamed user-facing machine to just "virt" * removed the A9 support (it can't work since the A9 has no generic timers) * added virtio-mmio transports instead of random set of 'soc' devices (though we retain a pl011 UART) * instead of updating io_base as we step through adding devices, define a memory map with an array (similar to vexpress) * similarly, define irqmap with an array * folded in some minor fixes from John's aarch64-support patch * rather than explicitly doing endian-swapping on FDT cells, use fdt APIs that let us just pass in host-endian values and let the fdt layer take care of the swapping * miscellaneous minor code cleanups and style fixes ] Signed-off-by: Peter Maydell --- hw/arm/Makefile.objs | 2 +- hw/arm/virt.c | 444 +++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 445 insertions(+), 1 deletion(-) create mode 100644 hw/arm/virt.c (limited to 'hw/arm') diff --git a/hw/arm/Makefile.objs b/hw/arm/Makefile.objs index 3671b42738..78b56149b6 100644 --- a/hw/arm/Makefile.objs +++ b/hw/arm/Makefile.objs @@ -1,7 +1,7 @@ obj-y += boot.o collie.o exynos4_boards.o gumstix.o highbank.o obj-y += integratorcp.o kzm.o mainstone.o musicpal.o nseries.o obj-y += omap_sx1.o palm.o realview.o spitz.o stellaris.o -obj-y += tosa.o versatilepb.o vexpress.o xilinx_zynq.o z2.o +obj-y += tosa.o versatilepb.o vexpress.o virt.o xilinx_zynq.o z2.o obj-y += armv7m.o exynos4210.o pxa2xx.o pxa2xx_gpio.o pxa2xx_pic.o obj-y += omap1.o omap2.o strongarm.o diff --git a/hw/arm/virt.c b/hw/arm/virt.c new file mode 100644 index 0000000000..1e42cc2666 --- /dev/null +++ b/hw/arm/virt.c @@ -0,0 +1,444 @@ +/* + * 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, +}; + +typedef struct MemMapEntry { + hwaddr base; + hwaddr size; +} MemMapEntry; + +typedef struct VirtBoardInfo { + struct arm_boot_info bootinfo; + const char *cpu_model; + const char *qdevname; + const char *gic_compatible; + 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. + */ +static const MemMapEntry a15memmap[] = { + /* Space up to 0x8000000 is reserved for a boot ROM */ + [VIRT_FLASH] = { 0, 0x8000000 }, + [VIRT_CPUPERIPHS] = { 0x8000000, 0x8000 }, + /* GIC distributor and CPU interfaces sit inside the CPU peripheral space */ + [VIRT_GIC_DIST] = { 0x8001000, 0x1000 }, + [VIRT_GIC_CPU] = { 0x8002000, 0x1000 }, + [VIRT_UART] = { 0x9000000, 0x1000 }, + [VIRT_MMIO] = { 0xa000000, 0x200 }, + /* ...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_MMIO] = 16, /* ...to 16 + NUM_VIRTIO_TRANSPORTS - 1 */ +}; + +static VirtBoardInfo machines[] = { + { + .cpu_model = "cortex-a15", + .qdevname = "a15mpcore_priv", + .gic_compatible = "arm,cortex-a15-gic", + .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_devtree_setprop_string(fdt, "/", "compatible", "linux,dummy-virt"); + qemu_devtree_setprop_cell(fdt, "/", "#address-cells", 0x2); + qemu_devtree_setprop_cell(fdt, "/", "#size-cells", 0x2); + + /* + * /chosen and /memory nodes must exist for load_dtb + * to fill in necessary properties later + */ + qemu_devtree_add_subnode(fdt, "/chosen"); + qemu_devtree_add_subnode(fdt, "/memory"); + qemu_devtree_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_devtree_alloc_phandle(fdt); + qemu_devtree_add_subnode(fdt, "/apb-pclk"); + qemu_devtree_setprop_string(fdt, "/apb-pclk", "compatible", "fixed-clock"); + qemu_devtree_setprop_cell(fdt, "/apb-pclk", "#clock-cells", 0x0); + qemu_devtree_setprop_cell(fdt, "/apb-pclk", "clock-frequency", 24000000); + qemu_devtree_setprop_string(fdt, "/apb-pclk", "clock-output-names", + "clk24mhz"); + qemu_devtree_setprop_cell(fdt, "/apb-pclk", "phandle", vbi->clock_phandle); + + /* No PSCI for TCG yet */ + if (kvm_enabled()) { + qemu_devtree_add_subnode(fdt, "/psci"); + qemu_devtree_setprop_string(fdt, "/psci", "compatible", "arm,psci"); + qemu_devtree_setprop_string(fdt, "/psci", "method", "hvc"); + qemu_devtree_setprop_cell(fdt, "/psci", "cpu_suspend", + PSCI_FN_CPU_SUSPEND); + qemu_devtree_setprop_cell(fdt, "/psci", "cpu_off", PSCI_FN_CPU_OFF); + qemu_devtree_setprop_cell(fdt, "/psci", "cpu_on", PSCI_FN_CPU_ON); + qemu_devtree_setprop_cell(fdt, "/psci", "migrate", PSCI_FN_MIGRATE); + } +} + +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_devtree_add_subnode(vbi->fdt, "/timer"); + qemu_devtree_setprop_string(vbi->fdt, "/timer", + "compatible", "arm,armv7-timer"); + qemu_devtree_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_devtree_add_subnode(vbi->fdt, "/cpus"); + qemu_devtree_setprop_cell(vbi->fdt, "/cpus", "#address-cells", 0x1); + qemu_devtree_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_devtree_add_subnode(vbi->fdt, nodename); + qemu_devtree_setprop_string(vbi->fdt, nodename, "device_type", "cpu"); + qemu_devtree_setprop_string(vbi->fdt, nodename, "compatible", + armcpu->dtb_compatible); + + if (vbi->smp_cpus > 1) { + qemu_devtree_setprop_string(vbi->fdt, nodename, + "enable-method", "psci"); + } + + qemu_devtree_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_devtree_alloc_phandle(vbi->fdt); + qemu_devtree_setprop_cell(vbi->fdt, "/", "interrupt-parent", gic_phandle); + + qemu_devtree_add_subnode(vbi->fdt, "/intc"); + qemu_devtree_setprop_string(vbi->fdt, "/intc", "compatible", + vbi->gic_compatible); + qemu_devtree_setprop_cell(vbi->fdt, "/intc", "#interrupt-cells", 3); + qemu_devtree_setprop(vbi->fdt, "/intc", "interrupt-controller", NULL, 0); + qemu_devtree_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_devtree_setprop_cell(vbi->fdt, "/intc", "phandle", gic_phandle); +} + +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_devtree_add_subnode(vbi->fdt, nodename); + /* Note that we can't use setprop_string because of the embedded NUL */ + qemu_devtree_setprop(vbi->fdt, nodename, "compatible", + compat, sizeof(compat)); + qemu_devtree_setprop_sized_cells(vbi->fdt, nodename, "reg", + 2, base, 2, size); + qemu_devtree_setprop_cells(vbi->fdt, nodename, "interrupts", + GIC_FDT_IRQ_TYPE_SPI, irq, + GIC_FDT_IRQ_FLAGS_EDGE_LO_HI); + qemu_devtree_setprop_cells(vbi->fdt, nodename, "clocks", + vbi->clock_phandle, vbi->clock_phandle); + qemu_devtree_setprop(vbi->fdt, nodename, "clock-names", + clocknames, sizeof(clocknames)); + 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_devtree_add_subnode(vbi->fdt, nodename); + qemu_devtree_setprop_string(vbi->fdt, nodename, + "compatible", "virtio,mmio"); + qemu_devtree_setprop_sized_cells(vbi->fdt, nodename, "reg", + 2, base, 2, size); + qemu_devtree_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(QEMUMachineInitArgs *args) +{ + qemu_irq pic[NUM_IRQS]; + MemoryRegion *sysmem = get_system_memory(); + int n; + MemoryRegion *ram = g_new(MemoryRegion, 1); + DeviceState *dev; + SysBusDevice *busdev; + const char *cpu_model = args->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 (args->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); + } + object_property_set_bool(cpuobj, true, "realized", NULL); + } + fdt_add_cpu_nodes(vbi); + + memory_region_init_ram(ram, NULL, "mach-virt.ram", args->ram_size); + vmstate_register_ram_global(ram); + memory_region_add_subregion(sysmem, vbi->memmap[VIRT_MEM].base, ram); + + dev = qdev_create(NULL, vbi->qdevname); + qdev_prop_set_uint32(dev, "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(dev, "num-irq", NUM_IRQS + 32); + qdev_init_nofail(dev); + busdev = SYS_BUS_DEVICE(dev); + sysbus_mmio_map(busdev, 0, vbi->memmap[VIRT_CPUPERIPHS].base); + fdt_add_gic_node(vbi); + for (n = 0; n < smp_cpus; n++) { + DeviceState *cpudev = DEVICE(qemu_get_cpu(n)); + + sysbus_connect_irq(busdev, n, qdev_get_gpio_in(cpudev, ARM_CPU_IRQ)); + } + + for (n = 0; n < NUM_IRQS; n++) { + pic[n] = qdev_get_gpio_in(dev, n); + } + + create_uart(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 = args->ram_size; + vbi->bootinfo.kernel_filename = args->kernel_filename; + vbi->bootinfo.kernel_cmdline = args->kernel_cmdline; + vbi->bootinfo.initrd_filename = args->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 = 4, +}; + +static void machvirt_machine_init(void) +{ + qemu_register_machine(&machvirt_a15_machine); +} + +machine_init(machvirt_machine_init); -- cgit v1.2.1