Re: [Qemu-devel] [PATCH-for-4.2 v10 05/11] hw/arm/virt: Enable device memory cold/hot plug with ACPI boot

[Igor Mammedov <imammedo@redhat.com>]

On Wed, 4 Sep 2019 09:56:23 +0100
Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> wrote:

> This initializes the GED device with base memory and irq, configures
> ged memory hotplug event and builds the corresponding aml code. With
> this, both hot and cold plug of device memory is enabled now for Guest
> with ACPI boot. Memory cold plug support with Guest DT boot is not yet
> supported.
> 
> As DSDT table gets changed by this, update bios-tables-test-allowed-diff.h
> to avoid "make check" failure.
> 
> Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
> ---
> v9 --> v10
>  -updated commit log with bios-tables-test-allowed-diff.h info.
>  -Removed object_property_add_child() from create_acpi_ged().
> 
> v8 --> v9
>  -Changes related to GED being a TYPE_SYS_BUS_DEVICE now.
>  -Error propagation to _plug() handler.
>  -Removed R-by by Eric for now.
> 
> v7 --> v8
>  -Changed no_acpi_dev to no_ged.
>  -Fixed 'dev' reference leak by object_new().
>  -Updated bios-tables-test-allowed-diff.h to avoid "make check"
>   failure.
> 
> ---
>  hw/arm/Kconfig                        |  2 +
>  hw/arm/virt-acpi-build.c              | 16 +++++++
>  hw/arm/virt.c                         | 60 +++++++++++++++++++++++----
>  include/hw/arm/virt.h                 |  4 ++
>  tests/bios-tables-test-allowed-diff.h |  1 +
>  5 files changed, 76 insertions(+), 7 deletions(-)
> 
> diff --git a/hw/arm/Kconfig b/hw/arm/Kconfig
> index 39d285ad3d..c6e7782580 100644
> --- a/hw/arm/Kconfig
> +++ b/hw/arm/Kconfig
> @@ -22,6 +22,8 @@ config ARM_VIRT
>      select ACPI_PCI
>      select MEM_DEVICE
>      select DIMM
> +    select ACPI_MEMORY_HOTPLUG
> +    select ACPI_HW_REDUCED
>  
>  config CHEETAH
>      bool
> diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
> index a8b2d97fe9..5063f28812 100644
> --- a/hw/arm/virt-acpi-build.c
> +++ b/hw/arm/virt-acpi-build.c
> @@ -39,6 +39,8 @@
>  #include "hw/acpi/aml-build.h"
>  #include "hw/acpi/utils.h"
>  #include "hw/acpi/pci.h"
> +#include "hw/acpi/memory_hotplug.h"
> +#include "hw/acpi/generic_event_device.h"
>  #include "hw/pci/pcie_host.h"
>  #include "hw/pci/pci.h"
>  #include "hw/arm/virt.h"
> @@ -706,6 +708,7 @@ static void
>  build_dsdt(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
>  {
>      Aml *scope, *dsdt;
> +    MachineState *ms = MACHINE(vms);
>      const MemMapEntry *memmap = vms->memmap;
>      const int *irqmap = vms->irqmap;
>  
> @@ -730,6 +733,19 @@ build_dsdt(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
>                        vms->highmem, vms->highmem_ecam);
>      acpi_dsdt_add_gpio(scope, &memmap[VIRT_GPIO],
>                         (irqmap[VIRT_GPIO] + ARM_SPI_BASE));
> +    if (vms->acpi_dev) {
> +        build_ged_aml(scope, "\\_SB."GED_DEVICE,
> +                      HOTPLUG_HANDLER(vms->acpi_dev),
> +                      irqmap[VIRT_ACPI_GED] + ARM_SPI_BASE, AML_SYSTEM_MEMORY,
> +                      memmap[VIRT_ACPI_GED].base);
> +    }
> +
> +    if (vms->acpi_dev && ms->ram_slots) {
> +        build_memory_hotplug_aml(scope, ms->ram_slots, "\\_SB", NULL,
> +                                 AML_SYSTEM_MEMORY,
> +                                 memmap[VIRT_PCDIMM_ACPI].base);
> +    }
> +
>      acpi_dsdt_add_power_button(scope);
>  
>      aml_append(dsdt, scope);
> diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> index 7c492c31a0..b99c12ad9c 100644
> --- a/hw/arm/virt.c
> +++ b/hw/arm/virt.c
> @@ -70,6 +70,7 @@
>  #include "target/arm/internals.h"
>  #include "hw/mem/pc-dimm.h"
>  #include "hw/mem/nvdimm.h"
> +#include "hw/acpi/generic_event_device.h"
>  
>  #define DEFINE_VIRT_MACHINE_LATEST(major, minor, latest) \
>      static void virt_##major##_##minor##_class_init(ObjectClass *oc, \
> @@ -140,6 +141,8 @@ static const MemMapEntry base_memmap[] = {
>      [VIRT_GPIO] =               { 0x09030000, 0x00001000 },
>      [VIRT_SECURE_UART] =        { 0x09040000, 0x00001000 },
>      [VIRT_SMMU] =               { 0x09050000, 0x00020000 },
> +    [VIRT_PCDIMM_ACPI] =        { 0x09070000, MEMORY_HOTPLUG_IO_LEN },
> +    [VIRT_ACPI_GED] =           { 0x09080000, ACPI_GED_EVT_SEL_LEN },
>      [VIRT_MMIO] =               { 0x0a000000, 0x00000200 },
>      /* ...repeating for a total of NUM_VIRTIO_TRANSPORTS, each of that size */
>      [VIRT_PLATFORM_BUS] =       { 0x0c000000, 0x02000000 },
> @@ -175,6 +178,7 @@ static const int a15irqmap[] = {
>      [VIRT_PCIE] = 3, /* ... to 6 */
>      [VIRT_GPIO] = 7,
>      [VIRT_SECURE_UART] = 8,
> +    [VIRT_ACPI_GED] = 9,
>      [VIRT_MMIO] = 16, /* ...to 16 + NUM_VIRTIO_TRANSPORTS - 1 */
>      [VIRT_GIC_V2M] = 48, /* ...to 48 + NUM_GICV2M_SPIS - 1 */
>      [VIRT_SMMU] = 74,    /* ...to 74 + NUM_SMMU_IRQS - 1 */
> @@ -524,6 +528,24 @@ static void fdt_add_pmu_nodes(const VirtMachineState *vms)
>      }
>  }
>  
> +static inline DeviceState *create_acpi_ged(VirtMachineState *vms, qemu_irq *pic)
> +{
> +    DeviceState *dev;
> +    int irq = vms->irqmap[VIRT_ACPI_GED];
> +    uint32_t event = ACPI_GED_MEM_HOTPLUG_EVT;
> +
> +    dev = qdev_create(NULL, TYPE_ACPI_GED);
> +    qdev_prop_set_uint32(dev, "ged-event", event);

> +    qdev_init_nofail(dev)
I suggest to move this line past property initialization
(i.e. sysbus_connect_irq) so it would follow typical QOM object init flow.
 
> +
> +    sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, vms->memmap[VIRT_ACPI_GED].base);
> +    sysbus_mmio_map(SYS_BUS_DEVICE(dev), 1, vms->memmap[VIRT_PCDIMM_ACPI].base);
> +
> +    sysbus_connect_irq(SYS_BUS_DEVICE(dev), 0, pic[irq]);
> +
> +    return dev;
> +}
> +
>  static void create_its(VirtMachineState *vms, DeviceState *gicdev)
>  {
>      const char *itsclass = its_class_name();
> @@ -1487,6 +1509,7 @@ static void machvirt_init(MachineState *machine)
>      MemoryRegion *ram = g_new(MemoryRegion, 1);
>      bool firmware_loaded;
>      bool aarch64 = true;
> +    bool has_ged = !vmc->no_ged;
>      unsigned int smp_cpus = machine->smp.cpus;
>      unsigned int max_cpus = machine->smp.max_cpus;
>  
> @@ -1701,6 +1724,10 @@ static void machvirt_init(MachineState *machine)
>  
>      create_gpio(vms, pic);
>  
> +    if (has_ged && aarch64 && firmware_loaded && acpi_enabled) {
> +        vms->acpi_dev = create_acpi_ged(vms, 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.
> @@ -1880,14 +1907,23 @@ static const CPUArchIdList *virt_possible_cpu_arch_ids(MachineState *ms)
>  static void virt_memory_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
>                                   Error **errp)
>  {
> +    VirtMachineState *vms = VIRT_MACHINE(hotplug_dev);
> +    const bool is_nvdimm = object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM);
> +    Error *local_err = NULL;
>  
> -    /*
> -     * The device memory is not yet exposed to the Guest either through
> -     * DT or ACPI and hence both cold/hot plug of memory is explicitly
> -     * disabled for now.
> -     */
> -    if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
> -        error_setg(errp, "memory cold/hot plug is not yet supported");
> +    if (is_nvdimm) {
> +        error_setg(errp, "nvdimm is not yet supported");
> +        return;
> +    }
> +
> +    if (!vms->acpi_dev) {
> +        error_setg(errp, "memory hotplug is not enabled: missing acpi device");
It could be more clear if s/acpi/acpi-ged/
> +        return;
> +    }
> +
> +    hotplug_handler_pre_plug(HOTPLUG_HANDLER(vms->acpi_dev), dev, &local_err);
Does this call do anything?

> +    if (local_err) {
> +        error_propagate(errp, local_err);
>          return;
>      }
>  
> @@ -1897,11 +1933,18 @@ static void virt_memory_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
>  static void virt_memory_plug(HotplugHandler *hotplug_dev,
>                               DeviceState *dev, Error **errp)
>  {
> +    HotplugHandlerClass *hhc;
>      VirtMachineState *vms = VIRT_MACHINE(hotplug_dev);
>      Error *local_err = NULL;
>  
>      pc_dimm_plug(PC_DIMM(dev), MACHINE(vms), &local_err);
> +    if (local_err) {
> +        goto out;
> +    }
>  
> +    hhc = HOTPLUG_HANDLER_GET_CLASS(vms->acpi_dev);
> +    hhc->plug(HOTPLUG_HANDLER(vms->acpi_dev), dev, &local_err);
if error after this fails is recoverable, there should be code that
will undo whatever previous steps done.

There is no rollback in x86 case and we use error_abort
since it should never fail.

> +out:
>      error_propagate(errp, local_err);
>  }
>  
> @@ -2108,8 +2151,11 @@ DEFINE_VIRT_MACHINE_AS_LATEST(4, 2)
>  
>  static void virt_machine_4_1_options(MachineClass *mc)
>  {
> +    VirtMachineClass *vmc = VIRT_MACHINE_CLASS(OBJECT_CLASS(mc));
> +
>      virt_machine_4_2_options(mc);
>      compat_props_add(mc->compat_props, hw_compat_4_1, hw_compat_4_1_len);
> +    vmc->no_ged = true;
>  }
>  DEFINE_VIRT_MACHINE(4, 1)
>  
> diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h
> index a72094204e..577ee49b4b 100644
> --- a/include/hw/arm/virt.h
> +++ b/include/hw/arm/virt.h
> @@ -77,6 +77,8 @@ enum {
>      VIRT_GPIO,
>      VIRT_SECURE_UART,
>      VIRT_SECURE_MEM,
> +    VIRT_PCDIMM_ACPI,
> +    VIRT_ACPI_GED,
>      VIRT_LOWMEMMAP_LAST,
>  };
>  
> @@ -106,6 +108,7 @@ typedef struct {
>      bool claim_edge_triggered_timers;
>      bool smbios_old_sys_ver;
>      bool no_highmem_ecam;
> +    bool no_ged;   /* Machines < 4.2 has no support for ACPI GED device */
>  } VirtMachineClass;
>  
>  typedef struct {
> @@ -133,6 +136,7 @@ typedef struct {
>      uint32_t iommu_phandle;
>      int psci_conduit;
>      hwaddr highest_gpa;
> +    DeviceState *acpi_dev;
>  } VirtMachineState;
>  
>  #define VIRT_ECAM_ID(high) (high ? VIRT_HIGH_PCIE_ECAM : VIRT_PCIE_ECAM)
> diff --git a/tests/bios-tables-test-allowed-diff.h b/tests/bios-tables-test-allowed-diff.h
> index dfb8523c8b..7b4adbc822 100644
> --- a/tests/bios-tables-test-allowed-diff.h
> +++ b/tests/bios-tables-test-allowed-diff.h
> @@ -1 +1,2 @@
>  /* List of comma-separated changed AML files to ignore */
> +"tests/data/acpi/virt/DSDT",