Re: [Qemu-devel] [PATCH v3 2/6] hw/arm/dyn_sysbus_devtree: helpers for sysbus device dynamic dt node generation

[Paolo Bonzini <pbonzini@redhat.com>]

Il 09/09/2014 09:54, Eric Auger ha scritto:
> This module will be used by ARM machine files to generate
> device tree nodes of dynamically instantiated sysbus devices (ie.
> those instantiated with -device option).
> 
> Signed-off-by: Alexander Graf <agraf@suse.de>
> Signed-off-by: Eric Auger <eric.auger@linaro.org>
> 
> ---
> 
> v2 -> v3:
> - add arm_ prefix
> - arm_sysbus_device_create_devtree becomes static
> 
> v1 -> v2:
> - Code moved in an arch specific file to accomodate architecture
>   dependent specificities.
> - remove platform_bus_base from PlatformDevtreeData
> 
> v1: code originally written by Alex Graf in e500.c and reused for ARM
>     [Eric Auger]
>     code originally moved in hw/misc/platform_devices and device itself
> ---
>  hw/arm/Makefile.objs                |  1 +
>  hw/arm/dyn_sysbus_devtree.c         | 66 +++++++++++++++++++++++++++++++++++++

File names in QEMU typically use a dash instead of an underscore.  Also,
I see the "fdt" moniker used more often than "devtree" (ouch, I checked
now and it's 7 vs. 851 uses :)).  So what about hw/arm/sysbus-fdt.c?

>  include/hw/arm/dyn_sysbus_devtree.h | 16 +++++++++
>  3 files changed, 83 insertions(+)
>  create mode 100644 hw/arm/dyn_sysbus_devtree.c
>  create mode 100644 include/hw/arm/dyn_sysbus_devtree.h
> 
> diff --git a/hw/arm/Makefile.objs b/hw/arm/Makefile.objs
> index 6088e53..bc5e014 100644
> --- a/hw/arm/Makefile.objs
> +++ b/hw/arm/Makefile.objs
> @@ -3,6 +3,7 @@ obj-$(CONFIG_DIGIC) += digic_boards.o
>  obj-y += integratorcp.o kzm.o mainstone.o musicpal.o nseries.o
>  obj-y += omap_sx1.o palm.o realview.o spitz.o stellaris.o
>  obj-y += tosa.o versatilepb.o vexpress.o virt.o xilinx_zynq.o z2.o
> +obj-y += dyn_sysbus_devtree.o
>  
>  obj-y += armv7m.o exynos4210.o pxa2xx.o pxa2xx_gpio.o pxa2xx_pic.o
>  obj-$(CONFIG_DIGIC) += digic.o
> diff --git a/hw/arm/dyn_sysbus_devtree.c b/hw/arm/dyn_sysbus_devtree.c
> new file mode 100644
> index 0000000..6375024
> --- /dev/null
> +++ b/hw/arm/dyn_sysbus_devtree.c
> @@ -0,0 +1,66 @@
> +#include "hw/arm/dyn_sysbus_devtree.h"
> +#include "qemu/error-report.h"
> +#include "sysemu/device_tree.h"
> +
> +static int arm_sysbus_device_create_devtree(Object *obj, void *opaque)
> +{
> +    PlatformDevtreeData *data = opaque;
> +    Object *dev;
> +    SysBusDevice *sbdev;
> +    bool matched = false;
> +
> +    dev = object_dynamic_cast(obj, TYPE_SYS_BUS_DEVICE);
> +    sbdev = (SysBusDevice *)dev;
> +
> +    if (!sbdev) {
> +        /* Container, traverse it for children */
> +        return object_child_foreach(obj,
> +                                    arm_sysbus_device_create_devtree, data);
> +    }
> +
> +    if (!matched) {

Who is going to set "matched", since it doesn't escape?

> +        error_report("Device %s is not supported by this machine yet.",
> +                     qdev_fw_name(DEVICE(dev)));
> +        exit(1);
> +    }
> +
> +    return 0;
> +}
> +
> +void arm_platform_bus_create_devtree(DynSysbusParams *params,
> +                                 void *fdt, const char *intc)

Let's just call this arm_create_fdt_dynamic.

> +{
> +    gchar *node = g_strdup_printf("/platform@%"PRIx64,
> +                                  params->platform_bus_base);
> +    const char platcomp[] = "qemu,platform\0simple-bus";
> +    PlatformDevtreeData data;
> +    Object *container;
> +    uint64_t addr = params->platform_bus_base;
> +    uint64_t size = params->platform_bus_size;
> +    int irq_start = params->platform_bus_first_irq;
> +
> +    /* Create a /platform node that we can put all devices into */
> +    qemu_fdt_add_subnode(fdt, node);
> +    qemu_fdt_setprop(fdt, node, "compatible", platcomp, sizeof(platcomp));
> +
> +    /* Our platform bus region is less than 32bit big, so 1 cell is enough for
> +       address and size */
> +    qemu_fdt_setprop_cells(fdt, node, "#size-cells", 1);
> +    qemu_fdt_setprop_cells(fdt, node, "#address-cells", 1);
> +    qemu_fdt_setprop_cells(fdt, node, "ranges", 0, addr >> 32, addr, size);
> +
> +    qemu_fdt_setprop_phandle(fdt, node, "interrupt-parent", intc);
> +
> +    /* Loop through all devices and create nodes for known ones */
> +    data.fdt = fdt;
> +    data.intc = intc;
> +    data.irq_start = irq_start;
> +    data.node = node;

Why does arm_sysbus_device_create_devtree need intc and irq_start?

> +
> +    container = container_get(qdev_get_machine(), "/peripheral");
> +    arm_sysbus_device_create_devtree(container, &data);
> +    container = container_get(qdev_get_machine(), "/peripheral-anon");
> +    arm_sysbus_device_create_devtree(container, &data);
> +
> +    g_free(node);
> +}
> diff --git a/include/hw/arm/dyn_sysbus_devtree.h b/include/hw/arm/dyn_sysbus_devtree.h
> new file mode 100644
> index 0000000..b072365
> --- /dev/null
> +++ b/include/hw/arm/dyn_sysbus_devtree.h
> @@ -0,0 +1,16 @@
> +#ifndef HW_ARM_DYN_SYSBUS_DEVTREE_H
> +#define HW_ARM_DYN_SYSBUS_DEVTREE_H
> +
> +#include "hw/misc/dyn_sysbus_binding.h"
> +
> +typedef struct PlatformDevtreeData {
> +    void *fdt;
> +    const char *intc;
> +    int irq_start;
> +    const char *node;
> +} PlatformDevtreeData;
> +
> +void arm_platform_bus_create_devtree(DynSysbusParams *params,
> +                                    void *fdt, const char *intc);
> +
> +#endif
>