Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20181102' into staging

target-arm queue:
 * microbit: Add the UART to our nRF51 SoC model
 * Add a virtual Xilinx Versal board "xlnx-versal-virt"
 * hw/arm/virt: Set VIRT_COMPAT_3_0 compat
 * MAINTAINERS: Remove bouncing email in ARM ACPI
 * strongarm: mask off high[31:28] bits from dir and state registers
 * target/arm: Conditionalize some asserts on aarch32 support
 * hw/arm/xilinx_zynq: Use the ARRAY_SIZE macro

# gpg: Signature made Fri 02 Nov 2018 17:14:43 GMT
# gpg:                using RSA key 3C2525ED14360CDE
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>"
# gpg:                 aka "Peter Maydell <pmaydell@gmail.com>"
# gpg:                 aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>"
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83  15CF 3C25 25ED 1436 0CDE

* remotes/pmaydell/tags/pull-target-arm-20181102:
  hw/arm: versal: Add a virtual Xilinx Versal board
  hw/arm: versal: Add a model of Xilinx Versal SoC
  target/arm: Conditionalize some asserts on aarch32 support
  hw/arm/xilinx_zynq: Use the ARRAY_SIZE macro
  strongarm: mask off high[31:28] bits from dir and state registers
  MAINTAINERS: Remove bouncing email in ARM ACPI
  tests/boot-serial-test: Add microbit board testcase
  hw/arm/nrf51_soc: Connect UART to nRF51 SoC
  hw/char: Implement nRF51 SoC UART
  hw/arm/virt: Set VIRT_COMPAT_3_0 compat

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

11 files changed, 1182 insertions, 3 deletions

diff --git a/hw/arm/Makefile.objs b/hw/arm/Makefile.objs
index 5f88062..50c7b4a 100644
--- a/hw/arm/Makefile.objs
+++ b/hw/arm/Makefile.objs
@@ -26,6 +26,7 @@ obj-$(CONFIG_ALLWINNER_A10) += allwinner-a10.o cubieboard.o
 obj-$(CONFIG_RASPI) += bcm2835_peripherals.o bcm2836.o raspi.o
 obj-$(CONFIG_STM32F205_SOC) += stm32f205_soc.o
 obj-$(CONFIG_XLNX_ZYNQMP_ARM) += xlnx-zynqmp.o xlnx-zcu102.o
+obj-$(CONFIG_XLNX_VERSAL) += xlnx-versal.o xlnx-versal-virt.o
 obj-$(CONFIG_FSL_IMX25) += fsl-imx25.o imx25_pdk.o
 obj-$(CONFIG_FSL_IMX31) += fsl-imx31.o kzm.o
 obj-$(CONFIG_FSL_IMX6) += fsl-imx6.o sabrelite.o
diff --git a/hw/arm/microbit.c b/hw/arm/microbit.c
index e7d7411..a734e7f 100644
--- a/hw/arm/microbit.c
+++ b/hw/arm/microbit.c
@@ -12,6 +12,7 @@
 #include "qapi/error.h"
 #include "hw/boards.h"
 #include "hw/arm/arm.h"
+#include "sysemu/sysemu.h"
 #include "exec/address-spaces.h"
 
 #include "hw/arm/nrf51_soc.h"
@@ -35,6 +36,7 @@ static void microbit_init(MachineState *machine)
 
     sysbus_init_child_obj(OBJECT(machine), "nrf51", soc, sizeof(s->nrf51),
                           TYPE_NRF51_SOC);
+    qdev_prop_set_chr(DEVICE(&s->nrf51), "serial0", serial_hd(0));
     object_property_set_link(soc, OBJECT(system_memory), "memory",
                              &error_fatal);
     object_property_set_bool(soc, true, "realized", &error_fatal);
diff --git a/hw/arm/nrf51_soc.c b/hw/arm/nrf51_soc.c
index 1a59ef4..b89c1bd 100644
--- a/hw/arm/nrf51_soc.c
+++ b/hw/arm/nrf51_soc.c
@@ -43,9 +43,12 @@
 #define NRF51822_FLASH_SIZE     (256 * 1024)
 #define NRF51822_SRAM_SIZE      (16 * 1024)
 
+#define BASE_TO_IRQ(base) ((base >> 12) & 0x1F)
+
 static void nrf51_soc_realize(DeviceState *dev_soc, Error **errp)
 {
     NRF51State *s = NRF51_SOC(dev_soc);
+    MemoryRegion *mr;
     Error *err = NULL;
 
     if (!s->board_memory) {
@@ -82,6 +85,18 @@ static void nrf51_soc_realize(DeviceState *dev_soc, Error **errp)
     }
     memory_region_add_subregion(&s->container, SRAM_BASE, &s->sram);
 
+    /* UART */
+    object_property_set_bool(OBJECT(&s->uart), true, "realized", &err);
+    if (err) {
+        error_propagate(errp, err);
+        return;
+    }
+    mr = sysbus_mmio_get_region(SYS_BUS_DEVICE(&s->uart), 0);
+    memory_region_add_subregion_overlap(&s->container, UART_BASE, mr, 0);
+    sysbus_connect_irq(SYS_BUS_DEVICE(&s->uart), 0,
+                       qdev_get_gpio_in(DEVICE(&s->cpu),
+                       BASE_TO_IRQ(UART_BASE)));
+
     create_unimplemented_device("nrf51_soc.io", IOMEM_BASE, IOMEM_SIZE);
     create_unimplemented_device("nrf51_soc.ficr", FICR_BASE, FICR_SIZE);
     create_unimplemented_device("nrf51_soc.private",
@@ -99,6 +114,11 @@ static void nrf51_soc_init(Object *obj)
     qdev_prop_set_string(DEVICE(&s->cpu), "cpu-type",
                          ARM_CPU_TYPE_NAME("cortex-m0"));
     qdev_prop_set_uint32(DEVICE(&s->cpu), "num-irq", 32);
+
+    sysbus_init_child_obj(obj, "uart", &s->uart, sizeof(s->uart),
+                           TYPE_NRF51_UART);
+    object_property_add_alias(obj, "serial0", OBJECT(&s->uart), "chardev",
+                              &error_abort);
 }
 
 static Property nrf51_soc_properties[] = {
diff --git a/hw/arm/strongarm.c b/hw/arm/strongarm.c
index ec26273..644a9c4 100644
--- a/hw/arm/strongarm.c
+++ b/hw/arm/strongarm.c
@@ -587,12 +587,12 @@ static void strongarm_gpio_write(void *opaque, hwaddr offset,
 
     switch (offset) {
     case GPDR:        /* GPIO Pin-Direction registers */
-        s->dir = value;
+        s->dir = value & 0x0fffffff;
         strongarm_gpio_handler_update(s);
         break;
 
     case GPSR:        /* GPIO Pin-Output Set registers */
-        s->olevel |= value;
+        s->olevel |= value & 0x0fffffff;
         strongarm_gpio_handler_update(s);
         break;
 
diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index 9f67782..a2b8d8f 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -1871,6 +1871,9 @@ static void virt_machine_3_1_options(MachineClass *mc)
 }
 DEFINE_VIRT_MACHINE_AS_LATEST(3, 1)
 
+#define VIRT_COMPAT_3_0 \
+    HW_COMPAT_3_0
+
 static void virt_3_0_instance_init(Object *obj)
 {
     virt_3_1_instance_init(obj);
@@ -1879,6 +1882,7 @@ static void virt_3_0_instance_init(Object *obj)
 static void virt_machine_3_0_options(MachineClass *mc)
 {
     virt_machine_3_1_options(mc);
+    SET_MACHINE_COMPAT(mc, VIRT_COMPAT_3_0);
 }
 DEFINE_VIRT_MACHINE(3, 0)
 
diff --git a/hw/arm/xilinx_zynq.c b/hw/arm/xilinx_zynq.c
index f1496d2..57497b0 100644
--- a/hw/arm/xilinx_zynq.c
+++ b/hw/arm/xilinx_zynq.c
@@ -294,7 +294,7 @@ static void zynq_init(MachineState *machine)
     busdev = SYS_BUS_DEVICE(dev);
     sysbus_mmio_map(busdev, 0, 0xF8003000);
     sysbus_connect_irq(busdev, 0, pic[45-IRQ_OFFSET]); /* abort irq line */
-    for (n = 0; n < 8; ++n) { /* event irqs */
+    for (n = 0; n < ARRAY_SIZE(dma_irqs); ++n) { /* event irqs */
         sysbus_connect_irq(busdev, n + 1, pic[dma_irqs[n] - IRQ_OFFSET]);
     }
 
diff --git a/hw/arm/xlnx-versal-virt.c b/hw/arm/xlnx-versal-virt.c
new file mode 100644
index 0000000..1e31a3f
--- /dev/null
+++ b/hw/arm/xlnx-versal-virt.c
@@ -0,0 +1,494 @@
+/*
+ * Xilinx Versal Virtual board.
+ *
+ * Copyright (c) 2018 Xilinx Inc.
+ * Written by Edgar E. Iglesias
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 or
+ * (at your option) any later version.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/log.h"
+#include "qemu/error-report.h"
+#include "qapi/error.h"
+#include "sysemu/device_tree.h"
+#include "exec/address-spaces.h"
+#include "hw/boards.h"
+#include "hw/sysbus.h"
+#include "hw/arm/sysbus-fdt.h"
+#include "hw/arm/fdt.h"
+#include "cpu.h"
+#include "hw/arm/xlnx-versal.h"
+
+#define TYPE_XLNX_VERSAL_VIRT_MACHINE MACHINE_TYPE_NAME("xlnx-versal-virt")
+#define XLNX_VERSAL_VIRT_MACHINE(obj) \
+    OBJECT_CHECK(VersalVirt, (obj), TYPE_XLNX_VERSAL_VIRT_MACHINE)
+
+typedef struct VersalVirt {
+    MachineState parent_obj;
+
+    Versal soc;
+    MemoryRegion mr_ddr;
+
+    void *fdt;
+    int fdt_size;
+    struct {
+        uint32_t gic;
+        uint32_t ethernet_phy[2];
+        uint32_t clk_125Mhz;
+        uint32_t clk_25Mhz;
+    } phandle;
+    struct arm_boot_info binfo;
+
+    struct {
+        bool secure;
+    } cfg;
+} VersalVirt;
+
+static void fdt_create(VersalVirt *s)
+{
+    MachineClass *mc = MACHINE_GET_CLASS(s);
+    int i;
+
+    s->fdt = create_device_tree(&s->fdt_size);
+    if (!s->fdt) {
+        error_report("create_device_tree() failed");
+        exit(1);
+    }
+
+    /* Allocate all phandles.  */
+    s->phandle.gic = qemu_fdt_alloc_phandle(s->fdt);
+    for (i = 0; i < ARRAY_SIZE(s->phandle.ethernet_phy); i++) {
+        s->phandle.ethernet_phy[i] = qemu_fdt_alloc_phandle(s->fdt);
+    }
+    s->phandle.clk_25Mhz = qemu_fdt_alloc_phandle(s->fdt);
+    s->phandle.clk_125Mhz = qemu_fdt_alloc_phandle(s->fdt);
+
+    /* Create /chosen node for load_dtb.  */
+    qemu_fdt_add_subnode(s->fdt, "/chosen");
+
+    /* Header */
+    qemu_fdt_setprop_cell(s->fdt, "/", "interrupt-parent", s->phandle.gic);
+    qemu_fdt_setprop_cell(s->fdt, "/", "#size-cells", 0x2);
+    qemu_fdt_setprop_cell(s->fdt, "/", "#address-cells", 0x2);
+    qemu_fdt_setprop_string(s->fdt, "/", "model", mc->desc);
+    qemu_fdt_setprop_string(s->fdt, "/", "compatible", "xlnx-versal-virt");
+}
+
+static void fdt_add_clk_node(VersalVirt *s, const char *name,
+                             unsigned int freq_hz, uint32_t phandle)
+{
+    qemu_fdt_add_subnode(s->fdt, name);
+    qemu_fdt_setprop_cell(s->fdt, name, "phandle", phandle);
+    qemu_fdt_setprop_cell(s->fdt, name, "clock-frequency", freq_hz);
+    qemu_fdt_setprop_cell(s->fdt, name, "#clock-cells", 0x0);
+    qemu_fdt_setprop_string(s->fdt, name, "compatible", "fixed-clock");
+    qemu_fdt_setprop(s->fdt, name, "u-boot,dm-pre-reloc", NULL, 0);
+}
+
+static void fdt_add_cpu_nodes(VersalVirt *s, uint32_t psci_conduit)
+{
+    int i;
+
+    qemu_fdt_add_subnode(s->fdt, "/cpus");
+    qemu_fdt_setprop_cell(s->fdt, "/cpus", "#size-cells", 0x0);
+    qemu_fdt_setprop_cell(s->fdt, "/cpus", "#address-cells", 1);
+
+    for (i = XLNX_VERSAL_NR_ACPUS - 1; i >= 0; i--) {
+        char *name = g_strdup_printf("/cpus/cpu@%d", i);
+        ARMCPU *armcpu = ARM_CPU(qemu_get_cpu(i));
+
+        qemu_fdt_add_subnode(s->fdt, name);
+        qemu_fdt_setprop_cell(s->fdt, name, "reg", armcpu->mp_affinity);
+        if (psci_conduit != QEMU_PSCI_CONDUIT_DISABLED) {
+            qemu_fdt_setprop_string(s->fdt, name, "enable-method", "psci");
+        }
+        qemu_fdt_setprop_string(s->fdt, name, "device_type", "cpu");
+        qemu_fdt_setprop_string(s->fdt, name, "compatible",
+                                armcpu->dtb_compatible);
+        g_free(name);
+    }
+}
+
+static void fdt_add_gic_nodes(VersalVirt *s)
+{
+    char *nodename;
+
+    nodename = g_strdup_printf("/gic@%x", MM_GIC_APU_DIST_MAIN);
+    qemu_fdt_add_subnode(s->fdt, nodename);
+    qemu_fdt_setprop_cell(s->fdt, nodename, "phandle", s->phandle.gic);
+    qemu_fdt_setprop_cells(s->fdt, nodename, "interrupts",
+                           GIC_FDT_IRQ_TYPE_PPI, VERSAL_GIC_MAINT_IRQ,
+                           GIC_FDT_IRQ_FLAGS_LEVEL_HI);
+    qemu_fdt_setprop(s->fdt, nodename, "interrupt-controller", NULL, 0);
+    qemu_fdt_setprop_sized_cells(s->fdt, nodename, "reg",
+                                 2, MM_GIC_APU_DIST_MAIN,
+                                 2, MM_GIC_APU_DIST_MAIN_SIZE,
+                                 2, MM_GIC_APU_REDIST_0,
+                                 2, MM_GIC_APU_REDIST_0_SIZE);
+    qemu_fdt_setprop_cell(s->fdt, nodename, "#interrupt-cells", 3);
+    qemu_fdt_setprop_string(s->fdt, nodename, "compatible", "arm,gic-v3");
+}
+
+static void fdt_add_timer_nodes(VersalVirt *s)
+{
+    const char compat[] = "arm,armv8-timer";
+    uint32_t irqflags = GIC_FDT_IRQ_FLAGS_LEVEL_HI;
+
+    qemu_fdt_add_subnode(s->fdt, "/timer");
+    qemu_fdt_setprop_cells(s->fdt, "/timer", "interrupts",
+            GIC_FDT_IRQ_TYPE_PPI, VERSAL_TIMER_S_EL1_IRQ, irqflags,
+            GIC_FDT_IRQ_TYPE_PPI, VERSAL_TIMER_NS_EL1_IRQ, irqflags,
+            GIC_FDT_IRQ_TYPE_PPI, VERSAL_TIMER_VIRT_IRQ, irqflags,
+            GIC_FDT_IRQ_TYPE_PPI, VERSAL_TIMER_NS_EL2_IRQ, irqflags);
+    qemu_fdt_setprop(s->fdt, "/timer", "compatible",
+                     compat, sizeof(compat));
+}
+
+static void fdt_add_uart_nodes(VersalVirt *s)
+{
+    uint64_t addrs[] = { MM_UART1, MM_UART0 };
+    unsigned int irqs[] = { VERSAL_UART1_IRQ_0, VERSAL_UART0_IRQ_0 };
+    const char compat[] = "arm,pl011\0arm,sbsa-uart";
+    const char clocknames[] = "uartclk\0apb_pclk";
+    int i;
+
+    for (i = 0; i < ARRAY_SIZE(addrs); i++) {
+        char *name = g_strdup_printf("/uart@%" PRIx64, addrs[i]);
+        qemu_fdt_add_subnode(s->fdt, name);
+        qemu_fdt_setprop_cell(s->fdt, name, "current-speed", 115200);
+        qemu_fdt_setprop_cells(s->fdt, name, "clocks",
+                               s->phandle.clk_125Mhz, s->phandle.clk_125Mhz);
+        qemu_fdt_setprop(s->fdt, name, "clock-names",
+                         clocknames, sizeof(clocknames));
+
+        qemu_fdt_setprop_cells(s->fdt, name, "interrupts",
+                               GIC_FDT_IRQ_TYPE_SPI, irqs[i],
+                               GIC_FDT_IRQ_FLAGS_LEVEL_HI);
+        qemu_fdt_setprop_sized_cells(s->fdt, name, "reg",
+                                     2, addrs[i], 2, 0x1000);
+        qemu_fdt_setprop(s->fdt, name, "compatible",
+                         compat, sizeof(compat));
+        qemu_fdt_setprop(s->fdt, name, "u-boot,dm-pre-reloc", NULL, 0);
+
+        if (addrs[i] == MM_UART0) {
+            /* Select UART0.  */
+            qemu_fdt_setprop_string(s->fdt, "/chosen", "stdout-path", name);
+        }
+        g_free(name);
+    }
+}
+
+static void fdt_add_fixed_link_nodes(VersalVirt *s, char *gemname,
+                                     uint32_t phandle)
+{
+    char *name = g_strdup_printf("%s/fixed-link", gemname);
+
+    qemu_fdt_add_subnode(s->fdt, name);
+    qemu_fdt_setprop_cell(s->fdt, name, "phandle", phandle);
+    qemu_fdt_setprop(s->fdt, name, "full-duplex", NULL, 0);
+    qemu_fdt_setprop_cell(s->fdt, name, "speed", 1000);
+    g_free(name);
+}
+
+static void fdt_add_gem_nodes(VersalVirt *s)
+{
+    uint64_t addrs[] = { MM_GEM1, MM_GEM0 };
+    unsigned int irqs[] = { VERSAL_GEM1_IRQ_0, VERSAL_GEM0_IRQ_0 };
+    const char clocknames[] = "pclk\0hclk\0tx_clk\0rx_clk";
+    const char compat_gem[] = "cdns,zynqmp-gem\0cdns,gem";
+    int i;
+
+    for (i = 0; i < ARRAY_SIZE(addrs); i++) {
+        char *name = g_strdup_printf("/ethernet@%" PRIx64, addrs[i]);
+        qemu_fdt_add_subnode(s->fdt, name);
+
+        fdt_add_fixed_link_nodes(s, name, s->phandle.ethernet_phy[i]);
+        qemu_fdt_setprop_string(s->fdt, name, "phy-mode", "rgmii-id");
+        qemu_fdt_setprop_cell(s->fdt, name, "phy-handle",
+                              s->phandle.ethernet_phy[i]);
+        qemu_fdt_setprop_cells(s->fdt, name, "clocks",
+                               s->phandle.clk_25Mhz, s->phandle.clk_25Mhz,
+                               s->phandle.clk_25Mhz, s->phandle.clk_25Mhz);
+        qemu_fdt_setprop(s->fdt, name, "clock-names",
+                         clocknames, sizeof(clocknames));
+        qemu_fdt_setprop_cells(s->fdt, name, "interrupts",
+                               GIC_FDT_IRQ_TYPE_SPI, irqs[i],
+                               GIC_FDT_IRQ_FLAGS_LEVEL_HI,
+                               GIC_FDT_IRQ_TYPE_SPI, irqs[i],
+                               GIC_FDT_IRQ_FLAGS_LEVEL_HI);
+        qemu_fdt_setprop_sized_cells(s->fdt, name, "reg",
+                                     2, addrs[i], 2, 0x1000);
+        qemu_fdt_setprop(s->fdt, name, "compatible",
+                         compat_gem, sizeof(compat_gem));
+        qemu_fdt_setprop_cell(s->fdt, name, "#address-cells", 1);
+        qemu_fdt_setprop_cell(s->fdt, name, "#size-cells", 0);
+        g_free(name);
+    }
+}
+
+static void fdt_nop_memory_nodes(void *fdt, Error **errp)
+{
+    Error *err = NULL;
+    char **node_path;
+    int n = 0;
+
+    node_path = qemu_fdt_node_unit_path(fdt, "memory", &err);
+    if (err) {
+        error_propagate(errp, err);
+        return;
+    }
+    while (node_path[n]) {
+        if (g_str_has_prefix(node_path[n], "/memory")) {
+            qemu_fdt_nop_node(fdt, node_path[n]);
+        }
+        n++;
+    }
+    g_strfreev(node_path);
+}
+
+static void fdt_add_memory_nodes(VersalVirt *s, void *fdt, uint64_t ram_size)
+{
+    /* Describes the various split DDR access regions.  */
+    static const struct {
+        uint64_t base;
+        uint64_t size;
+    } addr_ranges[] = {
+        { MM_TOP_DDR, MM_TOP_DDR_SIZE },
+        { MM_TOP_DDR_2, MM_TOP_DDR_2_SIZE },
+        { MM_TOP_DDR_3, MM_TOP_DDR_3_SIZE },
+        { MM_TOP_DDR_4, MM_TOP_DDR_4_SIZE }
+    };
+    uint64_t mem_reg_prop[8] = {0};
+    uint64_t size = ram_size;
+    Error *err = NULL;
+    char *name;
+    int i;
+
+    fdt_nop_memory_nodes(fdt, &err);
+    if (err) {
+        error_report_err(err);
+        return;
+    }
+
+    name = g_strdup_printf("/memory@%x", MM_TOP_DDR);
+    for (i = 0; i < ARRAY_SIZE(addr_ranges) && size; i++) {
+        uint64_t mapsize;
+
+        mapsize = size < addr_ranges[i].size ? size : addr_ranges[i].size;
+
+        mem_reg_prop[i * 2] = addr_ranges[i].base;
+        mem_reg_prop[i * 2 + 1] = mapsize;
+        size -= mapsize;
+    }
+    qemu_fdt_add_subnode(fdt, name);
+    qemu_fdt_setprop_string(fdt, name, "device_type", "memory");
+
+    switch (i) {
+    case 1:
+        qemu_fdt_setprop_sized_cells(fdt, name, "reg",
+                                     2, mem_reg_prop[0],
+                                     2, mem_reg_prop[1]);
+        break;
+    case 2:
+        qemu_fdt_setprop_sized_cells(fdt, name, "reg",
+                                     2, mem_reg_prop[0],
+                                     2, mem_reg_prop[1],
+                                     2, mem_reg_prop[2],
+                                     2, mem_reg_prop[3]);
+        break;
+    case 3:
+        qemu_fdt_setprop_sized_cells(fdt, name, "reg",
+                                     2, mem_reg_prop[0],
+                                     2, mem_reg_prop[1],
+                                     2, mem_reg_prop[2],
+                                     2, mem_reg_prop[3],
+                                     2, mem_reg_prop[4],
+                                     2, mem_reg_prop[5]);
+        break;
+    case 4:
+        qemu_fdt_setprop_sized_cells(fdt, name, "reg",
+                                     2, mem_reg_prop[0],
+                                     2, mem_reg_prop[1],
+                                     2, mem_reg_prop[2],
+                                     2, mem_reg_prop[3],
+                                     2, mem_reg_prop[4],
+                                     2, mem_reg_prop[5],
+                                     2, mem_reg_prop[6],
+                                     2, mem_reg_prop[7]);
+        break;
+    default:
+        g_assert_not_reached();
+    }
+    g_free(name);
+}
+
+static void versal_virt_modify_dtb(const struct arm_boot_info *binfo,
+                                    void *fdt)
+{
+    VersalVirt *s = container_of(binfo, VersalVirt, binfo);
+
+    fdt_add_memory_nodes(s, fdt, binfo->ram_size);
+}
+
+static void *versal_virt_get_dtb(const struct arm_boot_info *binfo,
+                                  int *fdt_size)
+{
+    const VersalVirt *board = container_of(binfo, VersalVirt, binfo);
+
+    *fdt_size = board->fdt_size;
+    return board->fdt;
+}
+
+#define NUM_VIRTIO_TRANSPORT 32
+static void create_virtio_regions(VersalVirt *s)
+{
+    int virtio_mmio_size = 0x200;
+    int i;
+
+    for (i = 0; i < NUM_VIRTIO_TRANSPORT; i++) {
+        char *name = g_strdup_printf("virtio%d", i);;
+        hwaddr base = MM_TOP_RSVD + i * virtio_mmio_size;
+        int irq = VERSAL_RSVD_HIGH_IRQ_FIRST + i;
+        MemoryRegion *mr;
+        DeviceState *dev;
+        qemu_irq pic_irq;
+
+        pic_irq = qdev_get_gpio_in(DEVICE(&s->soc.fpd.apu.gic), irq);
+        dev = qdev_create(NULL, "virtio-mmio");
+        object_property_add_child(OBJECT(&s->soc), name, OBJECT(dev),
+                                  &error_fatal);
+        qdev_init_nofail(dev);
+        sysbus_connect_irq(SYS_BUS_DEVICE(dev), 0, pic_irq);
+        mr = sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 0);
+        memory_region_add_subregion(&s->soc.mr_ps, base, mr);
+        sysbus_create_simple("virtio-mmio", base, pic_irq);
+    }
+
+    for (i = 0; i < NUM_VIRTIO_TRANSPORT; i++) {
+        hwaddr base = MM_TOP_RSVD + i * virtio_mmio_size;
+        int irq = VERSAL_RSVD_HIGH_IRQ_FIRST + i;
+        char *name = g_strdup_printf("/virtio_mmio@%" PRIx64, base);
+
+        qemu_fdt_add_subnode(s->fdt, name);
+        qemu_fdt_setprop(s->fdt, name, "dma-coherent", NULL, 0);
+        qemu_fdt_setprop_cells(s->fdt, name, "interrupts",
+                               GIC_FDT_IRQ_TYPE_SPI, irq,
+                               GIC_FDT_IRQ_FLAGS_EDGE_LO_HI);
+        qemu_fdt_setprop_sized_cells(s->fdt, name, "reg",
+                                     2, base, 2, virtio_mmio_size);
+        qemu_fdt_setprop_string(s->fdt, name, "compatible", "virtio,mmio");
+        g_free(name);
+    }
+}
+
+static void versal_virt_init(MachineState *machine)
+{
+    VersalVirt *s = XLNX_VERSAL_VIRT_MACHINE(machine);
+    int psci_conduit = QEMU_PSCI_CONDUIT_DISABLED;
+
+    /*
+     * If the user provides an Operating System to be loaded, we expect them
+     * to use the -kernel command line option.
+     *
+     * Users can load firmware or boot-loaders with the -device loader options.
+     *
+     * When loading an OS, we generate a dtb and let arm_load_kernel() select
+     * where it gets loaded. This dtb will be passed to the kernel in x0.
+     *
+     * If there's no -kernel option, we generate a DTB and place it at 0x1000
+     * for the bootloaders or firmware to pick up.
+     *
+     * If users want to provide their own DTB, they can use the -dtb option.
+     * These dtb's will have their memory nodes modified to match QEMU's
+     * selected ram_size option before they get passed to the kernel or fw.
+     *
+     * When loading an OS, we turn on QEMU's PSCI implementation with SMC
+     * as the PSCI conduit. When there's no -kernel, we assume the user
+     * provides EL3 firmware to handle PSCI.
+     */
+    if (machine->kernel_filename) {
+        psci_conduit = QEMU_PSCI_CONDUIT_SMC;
+    }
+
+    memory_region_allocate_system_memory(&s->mr_ddr, NULL, "ddr",
+                                         machine->ram_size);
+
+    sysbus_init_child_obj(OBJECT(machine), "xlnx-ve", &s->soc,
+                          sizeof(s->soc), TYPE_XLNX_VERSAL);
+    object_property_set_link(OBJECT(&s->soc), OBJECT(&s->mr_ddr),
+                             "ddr", &error_abort);
+    object_property_set_int(OBJECT(&s->soc), psci_conduit,
+                            "psci-conduit", &error_abort);
+    object_property_set_bool(OBJECT(&s->soc), true, "realized", &error_fatal);
+
+    fdt_create(s);
+    create_virtio_regions(s);
+    fdt_add_gem_nodes(s);
+    fdt_add_uart_nodes(s);
+    fdt_add_gic_nodes(s);
+    fdt_add_timer_nodes(s);
+    fdt_add_cpu_nodes(s, psci_conduit);
+    fdt_add_clk_node(s, "/clk125", 125000000, s->phandle.clk_125Mhz);
+    fdt_add_clk_node(s, "/clk25", 25000000, s->phandle.clk_25Mhz);
+
+    /* Make the APU cpu address space visible to virtio and other
+     * modules unaware of muliple address-spaces.  */
+    memory_region_add_subregion_overlap(get_system_memory(),
+                                        0, &s->soc.fpd.apu.mr, 0);
+
+    s->binfo.ram_size = machine->ram_size;
+    s->binfo.kernel_filename = machine->kernel_filename;
+    s->binfo.kernel_cmdline = machine->kernel_cmdline;
+    s->binfo.initrd_filename = machine->initrd_filename;
+    s->binfo.loader_start = 0x0;
+    s->binfo.get_dtb = versal_virt_get_dtb;
+    s->binfo.modify_dtb = versal_virt_modify_dtb;
+    if (machine->kernel_filename) {
+        arm_load_kernel(s->soc.fpd.apu.cpu[0], &s->binfo);
+    } else {
+        AddressSpace *as = arm_boot_address_space(s->soc.fpd.apu.cpu[0],
+                                                  &s->binfo);
+        /* Some boot-loaders (e.g u-boot) don't like blobs at address 0 (NULL).
+         * Offset things by 4K.  */
+        s->binfo.loader_start = 0x1000;
+        s->binfo.dtb_limit = 0x1000000;
+        if (arm_load_dtb(s->binfo.loader_start,
+                         &s->binfo, s->binfo.dtb_limit, as) < 0) {
+            exit(EXIT_FAILURE);
+        }
+    }
+}
+
+static void versal_virt_machine_instance_init(Object *obj)
+{
+}
+
+static void versal_virt_machine_class_init(ObjectClass *oc, void *data)
+{
+    MachineClass *mc = MACHINE_CLASS(oc);
+
+    mc->desc = "Xilinx Versal Virtual development board";
+    mc->init = versal_virt_init;
+    mc->max_cpus = XLNX_VERSAL_NR_ACPUS;
+    mc->default_cpus = XLNX_VERSAL_NR_ACPUS;
+    mc->no_cdrom = true;
+}
+
+static const TypeInfo versal_virt_machine_init_typeinfo = {
+    .name       = TYPE_XLNX_VERSAL_VIRT_MACHINE,
+    .parent     = TYPE_MACHINE,
+    .class_init = versal_virt_machine_class_init,
+    .instance_init = versal_virt_machine_instance_init,
+    .instance_size = sizeof(VersalVirt),
+};
+
+static void versal_virt_machine_init_register_types(void)
+{
+    type_register_static(&versal_virt_machine_init_typeinfo);
+}
+
+type_init(versal_virt_machine_init_register_types)
+
diff --git a/hw/arm/xlnx-versal.c b/hw/arm/xlnx-versal.c
new file mode 100644
index 0000000..5ee58c0
--- /dev/null
+++ b/hw/arm/xlnx-versal.c
@@ -0,0 +1,323 @@
+/*
+ * Xilinx Versal SoC model.
+ *
+ * Copyright (c) 2018 Xilinx Inc.
+ * Written by Edgar E. Iglesias
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 or
+ * (at your option) any later version.
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "qemu-common.h"
+#include "qemu/log.h"
+#include "hw/sysbus.h"
+#include "net/net.h"
+#include "sysemu/sysemu.h"
+#include "sysemu/kvm.h"
+#include "hw/arm/arm.h"
+#include "kvm_arm.h"
+#include "hw/misc/unimp.h"
+#include "hw/intc/arm_gicv3_common.h"
+#include "hw/arm/xlnx-versal.h"
+
+#define XLNX_VERSAL_ACPU_TYPE ARM_CPU_TYPE_NAME("cortex-a72")
+#define GEM_REVISION        0x40070106
+
+static void versal_create_apu_cpus(Versal *s)
+{
+    int i;
+
+    for (i = 0; i < ARRAY_SIZE(s->fpd.apu.cpu); i++) {
+        Object *obj;
+        char *name;
+
+        obj = object_new(XLNX_VERSAL_ACPU_TYPE);
+        if (!obj) {
+            /* Secondary CPUs start in PSCI powered-down state */
+            error_report("Unable to create apu.cpu[%d] of type %s",
+                         i, XLNX_VERSAL_ACPU_TYPE);
+            exit(EXIT_FAILURE);
+        }
+
+        name = g_strdup_printf("apu-cpu[%d]", i);
+        object_property_add_child(OBJECT(s), name, obj, &error_fatal);
+        g_free(name);
+
+        object_property_set_int(obj, s->cfg.psci_conduit,
+                                "psci-conduit", &error_abort);
+        if (i) {
+            object_property_set_bool(obj, true,
+                                     "start-powered-off", &error_abort);
+        }
+
+        object_property_set_int(obj, ARRAY_SIZE(s->fpd.apu.cpu),
+                                "core-count", &error_abort);
+        object_property_set_link(obj, OBJECT(&s->fpd.apu.mr), "memory",
+                                 &error_abort);
+        object_property_set_bool(obj, true, "realized", &error_fatal);
+        s->fpd.apu.cpu[i] = ARM_CPU(obj);
+    }
+}
+
+static void versal_create_apu_gic(Versal *s, qemu_irq *pic)
+{
+    static const uint64_t addrs[] = {
+        MM_GIC_APU_DIST_MAIN,
+        MM_GIC_APU_REDIST_0
+    };
+    SysBusDevice *gicbusdev;
+    DeviceState *gicdev;
+    int nr_apu_cpus = ARRAY_SIZE(s->fpd.apu.cpu);
+    int i;
+
+    sysbus_init_child_obj(OBJECT(s), "apu-gic",
+                          &s->fpd.apu.gic, sizeof(s->fpd.apu.gic),
+                          gicv3_class_name());
+    gicbusdev = SYS_BUS_DEVICE(&s->fpd.apu.gic);
+    gicdev = DEVICE(&s->fpd.apu.gic);
+    qdev_prop_set_uint32(gicdev, "revision", 3);
+    qdev_prop_set_uint32(gicdev, "num-cpu", 2);
+    qdev_prop_set_uint32(gicdev, "num-irq", XLNX_VERSAL_NR_IRQS + 32);
+    qdev_prop_set_uint32(gicdev, "len-redist-region-count", 1);
+    qdev_prop_set_uint32(gicdev, "redist-region-count[0]", 2);
+    qdev_prop_set_bit(gicdev, "has-security-extensions", true);
+
+    object_property_set_bool(OBJECT(&s->fpd.apu.gic), true, "realized",
+                                    &error_fatal);
+
+    for (i = 0; i < ARRAY_SIZE(addrs); i++) {
+        MemoryRegion *mr;
+
+        mr = sysbus_mmio_get_region(gicbusdev, i);
+        memory_region_add_subregion(&s->fpd.apu.mr, addrs[i], mr);
+    }
+
+    for (i = 0; i < nr_apu_cpus; i++) {
+        DeviceState *cpudev = DEVICE(s->fpd.apu.cpu[i]);
+        int ppibase = XLNX_VERSAL_NR_IRQS + i * GIC_INTERNAL + GIC_NR_SGIS;
+        qemu_irq maint_irq;
+        int ti;
+        /* Mapping from the output timer irq lines from the CPU to the
+         * GIC PPI inputs.
+         */
+        const int timer_irq[] = {
+            [GTIMER_PHYS] = VERSAL_TIMER_NS_EL1_IRQ,
+            [GTIMER_VIRT] = VERSAL_TIMER_VIRT_IRQ,
+            [GTIMER_HYP]  = VERSAL_TIMER_NS_EL2_IRQ,
+            [GTIMER_SEC]  = VERSAL_TIMER_S_EL1_IRQ,
+        };
+
+        for (ti = 0; ti < ARRAY_SIZE(timer_irq); ti++) {
+            qdev_connect_gpio_out(cpudev, ti,
+                                  qdev_get_gpio_in(gicdev,
+                                                   ppibase + timer_irq[ti]));
+        }
+        maint_irq = qdev_get_gpio_in(gicdev,
+                                        ppibase + VERSAL_GIC_MAINT_IRQ);
+        qdev_connect_gpio_out_named(cpudev, "gicv3-maintenance-interrupt",
+                                    0, maint_irq);
+        sysbus_connect_irq(gicbusdev, i, qdev_get_gpio_in(cpudev, ARM_CPU_IRQ));
+        sysbus_connect_irq(gicbusdev, i + nr_apu_cpus,
+                           qdev_get_gpio_in(cpudev, ARM_CPU_FIQ));
+        sysbus_connect_irq(gicbusdev, i + 2 * nr_apu_cpus,
+                           qdev_get_gpio_in(cpudev, ARM_CPU_VIRQ));
+        sysbus_connect_irq(gicbusdev, i + 3 * nr_apu_cpus,
+                           qdev_get_gpio_in(cpudev, ARM_CPU_VFIQ));
+    }
+
+    for (i = 0; i < XLNX_VERSAL_NR_IRQS; i++) {
+        pic[i] = qdev_get_gpio_in(gicdev, i);
+    }
+}
+
+static void versal_create_uarts(Versal *s, qemu_irq *pic)
+{
+    int i;
+
+    for (i = 0; i < ARRAY_SIZE(s->lpd.iou.uart); i++) {
+        static const int irqs[] = { VERSAL_UART0_IRQ_0, VERSAL_UART1_IRQ_0};
+        static const uint64_t addrs[] = { MM_UART0, MM_UART1 };
+        char *name = g_strdup_printf("uart%d", i);
+        DeviceState *dev;
+        MemoryRegion *mr;
+
+        dev = qdev_create(NULL, "pl011");
+        s->lpd.iou.uart[i] = SYS_BUS_DEVICE(dev);
+        qdev_prop_set_chr(dev, "chardev", serial_hd(i));
+        object_property_add_child(OBJECT(s), name, OBJECT(dev), &error_fatal);
+        qdev_init_nofail(dev);
+
+        mr = sysbus_mmio_get_region(s->lpd.iou.uart[i], 0);
+        memory_region_add_subregion(&s->mr_ps, addrs[i], mr);
+
+        sysbus_connect_irq(s->lpd.iou.uart[i], 0, pic[irqs[i]]);
+        g_free(name);
+    }
+}
+
+static void versal_create_gems(Versal *s, qemu_irq *pic)
+{
+    int i;
+
+    for (i = 0; i < ARRAY_SIZE(s->lpd.iou.gem); i++) {
+        static const int irqs[] = { VERSAL_GEM0_IRQ_0, VERSAL_GEM1_IRQ_0};
+        static const uint64_t addrs[] = { MM_GEM0, MM_GEM1 };
+        char *name = g_strdup_printf("gem%d", i);
+        NICInfo *nd = &nd_table[i];
+        DeviceState *dev;
+        MemoryRegion *mr;
+
+        dev = qdev_create(NULL, "cadence_gem");
+        s->lpd.iou.gem[i] = SYS_BUS_DEVICE(dev);
+        object_property_add_child(OBJECT(s), name, OBJECT(dev), &error_fatal);
+        if (nd->used) {
+            qemu_check_nic_model(nd, "cadence_gem");
+            qdev_set_nic_properties(dev, nd);
+        }
+        object_property_set_int(OBJECT(s->lpd.iou.gem[i]),
+                                2, "num-priority-queues",
+                                &error_abort);
+        object_property_set_link(OBJECT(s->lpd.iou.gem[i]),
+                                 OBJECT(&s->mr_ps), "dma",
+                                 &error_abort);
+        qdev_init_nofail(dev);
+
+        mr = sysbus_mmio_get_region(s->lpd.iou.gem[i], 0);
+        memory_region_add_subregion(&s->mr_ps, addrs[i], mr);
+
+        sysbus_connect_irq(s->lpd.iou.gem[i], 0, pic[irqs[i]]);
+        g_free(name);
+    }
+}
+
+/* This takes the board allocated linear DDR memory and creates aliases
+ * for each split DDR range/aperture on the Versal address map.
+ */
+static void versal_map_ddr(Versal *s)
+{
+    uint64_t size = memory_region_size(s->cfg.mr_ddr);
+    /* Describes the various split DDR access regions.  */
+    static const struct {
+        uint64_t base;
+        uint64_t size;
+    } addr_ranges[] = {
+        { MM_TOP_DDR, MM_TOP_DDR_SIZE },
+        { MM_TOP_DDR_2, MM_TOP_DDR_2_SIZE },
+        { MM_TOP_DDR_3, MM_TOP_DDR_3_SIZE },
+        { MM_TOP_DDR_4, MM_TOP_DDR_4_SIZE }
+    };
+    uint64_t offset = 0;
+    int i;
+
+    assert(ARRAY_SIZE(addr_ranges) == ARRAY_SIZE(s->noc.mr_ddr_ranges));
+    for (i = 0; i < ARRAY_SIZE(addr_ranges) && size; i++) {
+        char *name;
+        uint64_t mapsize;
+
+        mapsize = size < addr_ranges[i].size ? size : addr_ranges[i].size;
+        name = g_strdup_printf("noc-ddr-range%d", i);
+        /* Create the MR alias.  */
+        memory_region_init_alias(&s->noc.mr_ddr_ranges[i], OBJECT(s),
+                                 name, s->cfg.mr_ddr,
+                                 offset, mapsize);
+
+        /* Map it onto the NoC MR.  */
+        memory_region_add_subregion(&s->mr_ps, addr_ranges[i].base,
+                                    &s->noc.mr_ddr_ranges[i]);
+        offset += mapsize;
+        size -= mapsize;
+        g_free(name);
+    }
+}
+
+static void versal_unimp_area(Versal *s, const char *name,
+                                MemoryRegion *mr,
+                                hwaddr base, hwaddr size)
+{
+    DeviceState *dev = qdev_create(NULL, TYPE_UNIMPLEMENTED_DEVICE);
+    MemoryRegion *mr_dev;
+
+    qdev_prop_set_string(dev, "name", name);
+    qdev_prop_set_uint64(dev, "size", size);
+    object_property_add_child(OBJECT(s), name, OBJECT(dev), &error_fatal);
+    qdev_init_nofail(dev);
+
+    mr_dev = sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 0);
+    memory_region_add_subregion(mr, base, mr_dev);
+}
+
+static void versal_unimp(Versal *s)
+{
+    versal_unimp_area(s, "psm", &s->mr_ps,
+                        MM_PSM_START, MM_PSM_END - MM_PSM_START);
+    versal_unimp_area(s, "crl", &s->mr_ps,
+                        MM_CRL, MM_CRL_SIZE);
+    versal_unimp_area(s, "crf", &s->mr_ps,
+                        MM_FPD_CRF, MM_FPD_CRF_SIZE);
+    versal_unimp_area(s, "iou-scntr", &s->mr_ps,
+                        MM_IOU_SCNTR, MM_IOU_SCNTR_SIZE);
+    versal_unimp_area(s, "iou-scntr-seucre", &s->mr_ps,
+                        MM_IOU_SCNTRS, MM_IOU_SCNTRS_SIZE);
+}
+
+static void versal_realize(DeviceState *dev, Error **errp)
+{
+    Versal *s = XLNX_VERSAL(dev);
+    qemu_irq pic[XLNX_VERSAL_NR_IRQS];
+
+    versal_create_apu_cpus(s);
+    versal_create_apu_gic(s, pic);
+    versal_create_uarts(s, pic);
+    versal_create_gems(s, pic);
+    versal_map_ddr(s);
+    versal_unimp(s);
+
+    /* Create the On Chip Memory (OCM).  */
+    memory_region_init_ram(&s->lpd.mr_ocm, OBJECT(s), "ocm",
+                           MM_OCM_SIZE, &error_fatal);
+
+    memory_region_add_subregion_overlap(&s->mr_ps, MM_OCM, &s->lpd.mr_ocm, 0);
+    memory_region_add_subregion_overlap(&s->fpd.apu.mr, 0, &s->mr_ps, 0);
+}
+
+static void versal_init(Object *obj)
+{
+    Versal *s = XLNX_VERSAL(obj);
+
+    memory_region_init(&s->fpd.apu.mr, obj, "mr-apu", UINT64_MAX);
+    memory_region_init(&s->mr_ps, obj, "mr-ps-switch", UINT64_MAX);
+}
+
+static Property versal_properties[] = {
+    DEFINE_PROP_LINK("ddr", Versal, cfg.mr_ddr, TYPE_MEMORY_REGION,
+                     MemoryRegion *),
+    DEFINE_PROP_UINT32("psci-conduit", Versal, cfg.psci_conduit, 0),
+    DEFINE_PROP_END_OF_LIST()
+};
+
+static void versal_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->realize = versal_realize;
+    dc->props = versal_properties;
+    /* No VMSD since we haven't got any top-level SoC state to save.  */
+}
+
+static const TypeInfo versal_info = {
+    .name = TYPE_XLNX_VERSAL,
+    .parent = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(Versal),
+    .instance_init = versal_init,
+    .class_init = versal_class_init,
+};
+
+static void versal_register_types(void)
+{
+    type_register_static(&versal_info);
+}
+
+type_init(versal_register_types);
diff --git a/hw/char/Makefile.objs b/hw/char/Makefile.objs
index b570531..c4947d7 100644
--- a/hw/char/Makefile.objs
+++ b/hw/char/Makefile.objs
@@ -1,5 +1,6 @@
 common-obj-$(CONFIG_IPACK) += ipoctal232.o
 common-obj-$(CONFIG_ESCC) += escc.o
+common-obj-$(CONFIG_NRF51_SOC) += nrf51_uart.o
 common-obj-$(CONFIG_PARALLEL) += parallel.o
 common-obj-$(CONFIG_PARALLEL) += parallel-isa.o
 common-obj-$(CONFIG_PL011) += pl011.o
diff --git a/hw/char/nrf51_uart.c b/hw/char/nrf51_uart.c
new file mode 100644
index 0000000..2f5fae6
--- /dev/null
+++ b/hw/char/nrf51_uart.c
@@ -0,0 +1,330 @@
+/*
+ * nRF51 SoC UART emulation
+ *
+ * See nRF51 Series Reference Manual, "29 Universal Asynchronous
+ * Receiver/Transmitter" for hardware specifications:
+ * http://infocenter.nordicsemi.com/pdf/nRF51_RM_v3.0.pdf
+ *
+ * Copyright (c) 2018 Julia Suvorova <jusual@mail.ru>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 or
+ * (at your option) any later version.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/log.h"
+#include "hw/char/nrf51_uart.h"
+#include "trace.h"
+
+static void nrf51_uart_update_irq(NRF51UARTState *s)
+{
+    bool irq = false;
+
+    irq |= (s->reg[R_UART_RXDRDY] &&
+            (s->reg[R_UART_INTEN] & R_UART_INTEN_RXDRDY_MASK));
+    irq |= (s->reg[R_UART_TXDRDY] &&
+            (s->reg[R_UART_INTEN] & R_UART_INTEN_TXDRDY_MASK));
+    irq |= (s->reg[R_UART_ERROR]  &&
+            (s->reg[R_UART_INTEN] & R_UART_INTEN_ERROR_MASK));
+    irq |= (s->reg[R_UART_RXTO]   &&
+            (s->reg[R_UART_INTEN] & R_UART_INTEN_RXTO_MASK));
+
+    qemu_set_irq(s->irq, irq);
+}
+
+static uint64_t uart_read(void *opaque, hwaddr addr, unsigned int size)
+{
+    NRF51UARTState *s = NRF51_UART(opaque);
+    uint64_t r;
+
+    if (!s->enabled) {
+        return 0;
+    }
+
+    switch (addr) {
+    case A_UART_RXD:
+        r = s->rx_fifo[s->rx_fifo_pos];
+        if (s->rx_started && s->rx_fifo_len) {
+            s->rx_fifo_pos = (s->rx_fifo_pos + 1) % UART_FIFO_LENGTH;
+            s->rx_fifo_len--;
+            if (s->rx_fifo_len) {
+                s->reg[R_UART_RXDRDY] = 1;
+                nrf51_uart_update_irq(s);
+            }
+            qemu_chr_fe_accept_input(&s->chr);
+        }
+        break;
+    case A_UART_INTENSET:
+    case A_UART_INTENCLR:
+    case A_UART_INTEN:
+        r = s->reg[R_UART_INTEN];
+        break;
+    default:
+        r = s->reg[addr / 4];
+        break;
+    }
+
+    trace_nrf51_uart_read(addr, r, size);
+
+    return r;
+}
+
+static gboolean uart_transmit(GIOChannel *chan, GIOCondition cond, void *opaque)
+{
+    NRF51UARTState *s = NRF51_UART(opaque);
+    int r;
+    uint8_t c = s->reg[R_UART_TXD];
+
+    s->watch_tag = 0;
+
+    r = qemu_chr_fe_write(&s->chr, &c, 1);
+    if (r <= 0) {
+        s->watch_tag = qemu_chr_fe_add_watch(&s->chr, G_IO_OUT | G_IO_HUP,
+                                             uart_transmit, s);
+        if (!s->watch_tag) {
+            /* The hardware has no transmit error reporting,
+             * so silently drop the byte
+             */
+            goto buffer_drained;
+        }
+        return FALSE;
+    }
+
+buffer_drained:
+    s->reg[R_UART_TXDRDY] = 1;
+    s->pending_tx_byte = false;
+    return FALSE;
+}
+
+static void uart_cancel_transmit(NRF51UARTState *s)
+{
+    if (s->watch_tag) {
+        g_source_remove(s->watch_tag);
+        s->watch_tag = 0;
+    }
+}
+
+static void uart_write(void *opaque, hwaddr addr,
+                       uint64_t value, unsigned int size)
+{
+    NRF51UARTState *s = NRF51_UART(opaque);
+
+    trace_nrf51_uart_write(addr, value, size);
+
+    if (!s->enabled && (addr != A_UART_ENABLE)) {
+        return;
+    }
+
+    switch (addr) {
+    case A_UART_TXD:
+        if (!s->pending_tx_byte && s->tx_started) {
+            s->reg[R_UART_TXD] = value;
+            s->pending_tx_byte = true;
+            uart_transmit(NULL, G_IO_OUT, s);
+        }
+        break;
+    case A_UART_INTEN:
+        s->reg[R_UART_INTEN] = value;
+        break;
+    case A_UART_INTENSET:
+        s->reg[R_UART_INTEN] |= value;
+        break;
+    case A_UART_INTENCLR:
+        s->reg[R_UART_INTEN] &= ~value;
+        break;
+    case A_UART_TXDRDY ... A_UART_RXTO:
+        s->reg[addr / 4] = value;
+        break;
+    case A_UART_ERRORSRC:
+        s->reg[addr / 4] &= ~value;
+        break;
+    case A_UART_RXD:
+        break;
+    case A_UART_RXDRDY:
+        if (value == 0) {
+            s->reg[R_UART_RXDRDY] = 0;
+        }
+        break;
+    case A_UART_STARTTX:
+        if (value == 1) {
+            s->tx_started = true;
+        }
+        break;
+    case A_UART_STARTRX:
+        if (value == 1) {
+            s->rx_started = true;
+        }
+        break;
+    case A_UART_ENABLE:
+        if (value) {
+            if (value == 4) {
+                s->enabled = true;
+            }
+            break;
+        }
+        s->enabled = false;
+        value = 1;
+        /* fall through */
+    case A_UART_SUSPEND:
+    case A_UART_STOPTX:
+        if (value == 1) {
+            s->tx_started = false;
+        }
+        /* fall through */
+    case A_UART_STOPRX:
+        if (addr != A_UART_STOPTX && value == 1) {
+            s->rx_started = false;
+            s->reg[R_UART_RXTO] = 1;
+        }
+        break;
+    default:
+        s->reg[addr / 4] = value;
+        break;
+    }
+    nrf51_uart_update_irq(s);
+}
+
+static const MemoryRegionOps uart_ops = {
+    .read =  uart_read,
+    .write = uart_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+};
+
+static void nrf51_uart_reset(DeviceState *dev)
+{
+    NRF51UARTState *s = NRF51_UART(dev);
+
+    s->pending_tx_byte = 0;
+
+    uart_cancel_transmit(s);
+
+    memset(s->reg, 0, sizeof(s->reg));
+
+    s->reg[R_UART_PSELRTS] = 0xFFFFFFFF;
+    s->reg[R_UART_PSELTXD] = 0xFFFFFFFF;
+    s->reg[R_UART_PSELCTS] = 0xFFFFFFFF;
+    s->reg[R_UART_PSELRXD] = 0xFFFFFFFF;
+    s->reg[R_UART_BAUDRATE] = 0x4000000;
+
+    s->rx_fifo_len = 0;
+    s->rx_fifo_pos = 0;
+    s->rx_started = false;
+    s->tx_started = false;
+    s->enabled = false;
+}
+
+static void uart_receive(void *opaque, const uint8_t *buf, int size)
+{
+
+    NRF51UARTState *s = NRF51_UART(opaque);
+    int i;
+
+    if (size == 0 || s->rx_fifo_len >= UART_FIFO_LENGTH) {
+        return;
+    }
+
+    for (i = 0; i < size; i++) {
+        uint32_t pos = (s->rx_fifo_pos + s->rx_fifo_len) % UART_FIFO_LENGTH;
+        s->rx_fifo[pos] = buf[i];
+        s->rx_fifo_len++;
+    }
+
+    s->reg[R_UART_RXDRDY] = 1;
+    nrf51_uart_update_irq(s);
+}
+
+static int uart_can_receive(void *opaque)
+{
+    NRF51UARTState *s = NRF51_UART(opaque);
+
+    return s->rx_started ? (UART_FIFO_LENGTH - s->rx_fifo_len) : 0;
+}
+
+static void uart_event(void *opaque, int event)
+{
+    NRF51UARTState *s = NRF51_UART(opaque);
+
+    if (event == CHR_EVENT_BREAK) {
+        s->reg[R_UART_ERRORSRC] |= 3;
+        s->reg[R_UART_ERROR] = 1;
+        nrf51_uart_update_irq(s);
+    }
+}
+
+static void nrf51_uart_realize(DeviceState *dev, Error **errp)
+{
+    NRF51UARTState *s = NRF51_UART(dev);
+
+    qemu_chr_fe_set_handlers(&s->chr, uart_can_receive, uart_receive,
+                             uart_event, NULL, s, NULL, true);
+}
+
+static void nrf51_uart_init(Object *obj)
+{
+    NRF51UARTState *s = NRF51_UART(obj);
+    SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
+
+    memory_region_init_io(&s->iomem, obj, &uart_ops, s,
+                          "nrf51_soc.uart", UART_SIZE);
+    sysbus_init_mmio(sbd, &s->iomem);
+    sysbus_init_irq(sbd, &s->irq);
+}
+
+static int nrf51_uart_post_load(void *opaque, int version_id)
+{
+    NRF51UARTState *s = NRF51_UART(opaque);
+
+    if (s->pending_tx_byte) {
+        s->watch_tag = qemu_chr_fe_add_watch(&s->chr, G_IO_OUT | G_IO_HUP,
+                                             uart_transmit, s);
+    }
+
+    return 0;
+}
+
+static const VMStateDescription nrf51_uart_vmstate = {
+    .name = "nrf51_soc.uart",
+    .post_load = nrf51_uart_post_load,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32_ARRAY(reg, NRF51UARTState, 0x56C),
+        VMSTATE_UINT8_ARRAY(rx_fifo, NRF51UARTState, UART_FIFO_LENGTH),
+        VMSTATE_UINT32(rx_fifo_pos, NRF51UARTState),
+        VMSTATE_UINT32(rx_fifo_len, NRF51UARTState),
+        VMSTATE_BOOL(rx_started, NRF51UARTState),
+        VMSTATE_BOOL(tx_started, NRF51UARTState),
+        VMSTATE_BOOL(pending_tx_byte, NRF51UARTState),
+        VMSTATE_BOOL(enabled, NRF51UARTState),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static Property nrf51_uart_properties[] = {
+    DEFINE_PROP_CHR("chardev", NRF51UARTState, chr),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void nrf51_uart_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->reset = nrf51_uart_reset;
+    dc->realize = nrf51_uart_realize;
+    dc->props = nrf51_uart_properties;
+    dc->vmsd = &nrf51_uart_vmstate;
+}
+
+static const TypeInfo nrf51_uart_info = {
+    .name = TYPE_NRF51_UART,
+    .parent = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(NRF51UARTState),
+    .instance_init = nrf51_uart_init,
+    .class_init = nrf51_uart_class_init
+};
+
+static void nrf51_uart_register_types(void)
+{
+    type_register_static(&nrf51_uart_info);
+}
+
+type_init(nrf51_uart_register_types)
diff --git a/hw/char/trace-events b/hw/char/trace-events
index b64213d..de34a74 100644
--- a/hw/char/trace-events
+++ b/hw/char/trace-events
@@ -73,3 +73,7 @@ cmsdk_apb_uart_receive(uint8_t c) "CMSDK APB UART: got character 0x%x from backe
 cmsdk_apb_uart_tx_pending(void) "CMSDK APB UART: character send to backend pending"
 cmsdk_apb_uart_tx(uint8_t c) "CMSDK APB UART: character 0x%x sent to backend"
 cmsdk_apb_uart_set_params(int speed) "CMSDK APB UART: params set to %d 8N1"
+
+# hw/char/nrf51_uart.c
+nrf51_uart_read(uint64_t addr, uint64_t r, unsigned int size) "addr 0x%" PRIx64 " value 0x%" PRIx64 " size %u"
+nrf51_uart_write(uint64_t addr, uint64_t value, unsigned int size) "addr 0x%" PRIx64 " value 0x%" PRIx64 " size %u"