Re: [Qemu-devel] [RFC v2 1/7] hw/misc/dyn_sysbus_binding: helpers for sysbus device dynamic binding

[Eric Auger]

On 08/11/2014 03:08 PM, Alexander Graf wrote:
> 
> On 08.08.14 17:03, Eric Auger wrote:
>> This new module implements routines which help in dynamic device
>> binding (mmio regions, irq). They are supposed to be used by machine
>> files that support dynamic sysbus instantiation.
>>
>> ---
>>
>> v1 -> v2:
>> - platform_devices renamed into dyn_sysbus_binding
>> - PlatformParams renamed into DynSysbusParams
>> - PlatformBusNotifier renamed into DynSysbusNotifier
>> - platform_bus_map_irq, platform_bus_map_mmio, sysbus_device_check,
>>    platform_bus_init become static
>> - PlatformBusInitData becomes private to the module
>> - page_shift becomes a member of DynSysbusParams
>>
>> v1: Dynamic sysbus device allocation fully written by Alex Graf.
>> Those functions were initially in ppc e500 machine file. Now moved to a
>> separate module.
>> PPCE500Params is replaced by a generic struct named PlatformParams
>>
>> Signed-off-by: Alexander Graf <address@hidden>
>> Signed-off-by: Eric Auger <address@hidden>
>> ---
>>   hw/misc/Makefile.objs                |   1 +
>>   hw/misc/dyn_sysbus_binding.c         | 163
>> +++++++++++++++++++++++++++++++++++
>>   include/hw/misc/dyn_sysbus_binding.h |  24 ++++++
>>   3 files changed, 188 insertions(+)
>>   create mode 100644 hw/misc/dyn_sysbus_binding.c
>>   create mode 100644 include/hw/misc/dyn_sysbus_binding.h
>>
>> diff --git a/hw/misc/Makefile.objs b/hw/misc/Makefile.objs
>> index 979e532..86f6243 100644
>> --- a/hw/misc/Makefile.objs
>> +++ b/hw/misc/Makefile.objs
>> @@ -41,3 +41,4 @@ obj-$(CONFIG_SLAVIO) += slavio_misc.o
>>   obj-$(CONFIG_ZYNQ) += zynq_slcr.o
>>     obj-$(CONFIG_PVPANIC) += pvpanic.o
>> +obj-y += dyn_sysbus_binding.o
>> diff --git a/hw/misc/dyn_sysbus_binding.c b/hw/misc/dyn_sysbus_binding.c
>> new file mode 100644
>> index 0000000..0f34f0b
>> --- /dev/null
>> +++ b/hw/misc/dyn_sysbus_binding.c
>> @@ -0,0 +1,163 @@
> 
> This file is missing a license header.
OK
> 
>> +#include "hw/misc/dyn_sysbus_binding.h"
>> +#include "qemu/error-report.h"
>> +
>> +typedef struct PlatformBusInitData {
>> +    unsigned long *used_irqs;
>> +    unsigned long *used_mem;
>> +    MemoryRegion *mem;
>> +    qemu_irq *irqs;
>> +    int device_count;
>> +    DynSysbusParams *params;
>> +} PlatformBusInitData;
>> +
>> +
>> +static int platform_bus_map_irq(DynSysbusParams *params,
>> +                                SysBusDevice *sbdev,
>> +                                int n, unsigned long *used_irqs,
>> +                                qemu_irq *platform_irqs)
>> +{
>> +    int max_irqs = params->platform_bus_num_irqs;
>> +    char *prop = g_strdup_printf("irq[%d]", n);
>> +    int irqn = object_property_get_int(OBJECT(sbdev), prop, NULL);
>> +
>> +    if (irqn == SYSBUS_DYNAMIC) {
>> +        /* Find the first available IRQ */
>> +        irqn = find_first_zero_bit(used_irqs, max_irqs);
>> +    }
>> +
>> +    if ((irqn >= max_irqs) || test_and_set_bit(irqn, used_irqs)) {
>> +        hw_error("IRQ %d is already allocated or no free IRQ left",
>> irqn);
>> +    }
>> +
>> +    sysbus_connect_irq(sbdev, n, platform_irqs[irqn]);
>> +    object_property_set_int(OBJECT(sbdev), irqn, prop, NULL);
>> +
>> +    g_free(prop);
>> +    return 0;
>> +}
>> +
>> +static int platform_bus_map_mmio(DynSysbusParams *params,
>> +                                 SysBusDevice *sbdev,
>> +                                 int n, unsigned long *used_mem,
>> +                                 MemoryRegion *pmem)
>> +{
>> +    MemoryRegion *device_mem = sbdev->mmio[n].memory;
>> +    uint64_t size = memory_region_size(device_mem);
>> +    uint64_t page_size = (1 << params->page_shift);
>> +    uint64_t page_mask = page_size - 1;
>> +    uint64_t size_pages = (size + page_mask) >> params->page_shift;
>> +    uint64_t max_size = params->platform_bus_size;
>> +    uint64_t max_pages = max_size >> params->page_shift;
>> +    char *prop = g_strdup_printf("mmio[%d]", n);
>> +    hwaddr addr = object_property_get_int(OBJECT(sbdev), prop, NULL);
>> +    int page;
>> +    int i;
>> +
>> +    page = addr >> params->page_shift;
>> +    if (addr == SYSBUS_DYNAMIC) {
>> +        uint64_t size_pages_align;
>> +
>> +        /* Align the region to at least its own size granularity */
>> +        if (is_power_of_2(size_pages)) {
>> +            size_pages_align = size_pages;
>> +        } else {
>> +            size_pages_align = pow2floor(size_pages) << 1;
>> +        }
>> +
>> +        /* Find the first available region that fits */
>> +        page = bitmap_find_next_zero_area(used_mem, max_pages, 0,
>> size_pages,
>> +                                          size_pages_align);
>> +
>> +        addr = (uint64_t)page << params->page_shift;
>> +    }
>> +
>> +    if (page >= max_pages || test_bit(page, used_mem) ||
>> +        (find_next_bit(used_mem, max_pages, page) < size_pages)) {
>> +        hw_error("Memory [%"PRIx64":%"PRIx64" is already allocated or "
>> +                 "no slot left", addr, size);
>> +    }
>> +
>> +    for (i = page; i < (page + size_pages); i++) {
>> +        set_bit(i, used_mem);
>> +    }
>> +
>> +    memory_region_add_subregion(pmem, addr, device_mem);
>> +    sbdev->mmio[n].addr = addr;
>> +    object_property_set_int(OBJECT(sbdev), addr, prop, NULL);
>> +
>> +    g_free(prop);
>> +    return 0;
>> +}
>> +
>> +static int sysbus_device_check(Object *obj, void *opaque)
>> +{
>> +    PlatformBusInitData *init = opaque;
>> +    Object *dev;
>> +    SysBusDevice *sbdev;
>> +    int i;
>> +
>> +    dev = object_dynamic_cast(obj, TYPE_SYS_BUS_DEVICE);
>> +    sbdev = (SysBusDevice *)dev;
>> +
>> +    if (!sbdev) {
>> +        /* Container, traverse it for children */
>> +        return object_child_foreach(obj, sysbus_device_check, opaque);
>> +    }
>> +
>> +    /* Connect sysbus device to virtual platform bus */
>> +    for (i = 0; i < sbdev->num_irq; i++) {
>> +        if (!sbdev->irqp[i]) {
>> +            /* This IRQ is an incoming IRQ, we can't wire those here */
>> +            continue;
>> +        }
>> +        platform_bus_map_irq(init->params, sbdev, i,
>> +                             init->used_irqs, init->irqs);
>> +    }
>> +
>> +    for (i = 0; i < sbdev->num_mmio; i++) {
>> +        platform_bus_map_mmio(init->params, sbdev, i,
>> +                              init->used_mem, init->mem);
>> +    }
>> +
>> +    return 0;
>> +}
>> +
>> +static void platform_bus_init(DynSysbusParams *params,
>> +                       MemoryRegion *address_space_mem,
>> +                       qemu_irq *mpic)
> 
> You probably don't want to call it "mpic" in generic code - you're using
> a GIC after all on ARM.
yes, will change that
> 
> Also I think it'd be better if you actually transform my patch set into
> the generic variant. That way I can push mine upstream and then your
> patch set makes that copy generic.
OK I will do that

thanks

Eric
> 
> 
> Alex
> 
>> +{
>> +    uint64_t max_size = params->platform_bus_size;
>> +    uint64_t max_pages = max_size >> params->page_shift;
>> +    DECLARE_BITMAP(used_irqs, params->platform_bus_num_irqs);
>> +    DECLARE_BITMAP(used_mem, max_pages);
>> +    MemoryRegion *platform_region = g_new(MemoryRegion, 1);
>> +    Object *container;
>> +    PlatformBusInitData init = {
>> +        .used_irqs = used_irqs,
>> +        .used_mem = used_mem,
>> +        .mem = platform_region,
>> +        .irqs = &mpic[params->platform_bus_first_irq],
>> +        .params = params,
>> +    };
>> +
>> +    memory_region_init(platform_region, NULL, "platform devices",
>> +                       params->platform_bus_size);
>> +
>> +    bitmap_clear(used_irqs, 0, params->platform_bus_num_irqs);
>> +    bitmap_clear(used_mem, 0, max_pages);
>> +
>> +    /* Loop through all sysbus devices that were spawened outside the
>> machine */
>> +    container = container_get(qdev_get_machine(), "/peripheral");
>> +    sysbus_device_check(container, &init);
>> +    container = container_get(qdev_get_machine(), "/peripheral-anon");
>> +    sysbus_device_check(container, &init);
>> +
>> +    memory_region_add_subregion(address_space_mem,
>> params->platform_bus_base,
>> +                                platform_region);
>> +}
>> +
>> +void platform_bus_init_notify(Notifier *notifier, void *data)
>> +{
>> +    DynSysbusNotifier *pn = (DynSysbusNotifier *)notifier;
>> +    platform_bus_init(&pn->params, pn->address_space_mem, pn->mpic);
>> +}
>> diff --git a/include/hw/misc/dyn_sysbus_binding.h
>> b/include/hw/misc/dyn_sysbus_binding.h
>> new file mode 100644
>> index 0000000..961c9c7
>> --- /dev/null
>> +++ b/include/hw/misc/dyn_sysbus_binding.h
>> @@ -0,0 +1,24 @@
>> +#ifndef HW_MISC_PLATFORM_DEVICES_H
>> +#define HW_MISC_PLATFORM_DEVICES_H
>> +
>> +#include "qemu-common.h"
>> +#include "hw/sysbus.h"
>> +
>> +typedef struct {
>> +    bool has_platform_bus;
>> +    hwaddr platform_bus_base;
>> +    hwaddr platform_bus_size;
>> +    int platform_bus_first_irq;
>> +    int platform_bus_num_irqs;
>> +    int page_shift;
>> +} DynSysbusParams;
>> +
>> +typedef struct DynSysbusNotifier {
>> +    Notifier notifier;
>> +    MemoryRegion *address_space_mem;
>> +    qemu_irq *mpic;
>> +    DynSysbusParams params;
>> +} DynSysbusNotifier;
>> +
>> +void platform_bus_init_notify(Notifier *notifier, void *data);
>> +#endif
>