From 6a48c64eec355ab1aff694eb4522d07a8e461368 Mon Sep 17 00:00:00 2001 From: Gavin Shan Date: Wed, 14 Dec 2022 14:27:06 +0000 Subject: [PATCH] hw/arm/virt: Add properties to disable high memory regions The 3 high memory regions are usually enabled by default, but they may be not used. For example, VIRT_HIGH_GIC_REDIST2 isn't needed by GICv2. This leads to waste in the PA space. Add properties ("highmem-redists", "highmem-ecam", "highmem-mmio") to allow users selectively disable them if needed. After that, the high memory region for GICv3 or GICv4 redistributor can be disabled by user, the number of maximal supported CPUs needs to be calculated based on 'vms->highmem_redists'. The follow-up error message is also improved to indicate if the high memory region for GICv3 and GICv4 has been enabled or not. Suggested-by: Marc Zyngier Signed-off-by: Gavin Shan Reviewed-by: Marc Zyngier Reviewed-by: Cornelia Huck Reviewed-by: Eric Auger Message-id: 20221029224307.138822-8-gshan@redhat.com Signed-off-by: Peter Maydell --- docs/system/arm/virt.rst | 13 +++++++ hw/arm/virt.c | 75 ++++++++++++++++++++++++++++++++++++++-- 2 files changed, 86 insertions(+), 2 deletions(-) diff --git a/docs/system/arm/virt.rst b/docs/system/arm/virt.rst index 4454706392..188a4f211f 100644 --- a/docs/system/arm/virt.rst +++ b/docs/system/arm/virt.rst @@ -98,6 +98,19 @@ compact-highmem Set ``on``/``off`` to enable/disable the compact layout for high memory regions. The default is ``on`` for machine types later than ``virt-7.2``. +highmem-redists + Set ``on``/``off`` to enable/disable the high memory region for GICv3 or + GICv4 redistributor. The default is ``on``. Setting this to ``off`` will + limit the maximum number of CPUs when GICv3 or GICv4 is used. + +highmem-ecam + Set ``on``/``off`` to enable/disable the high memory region for PCI ECAM. + The default is ``on`` for machine types later than ``virt-3.0``. + +highmem-mmio + Set ``on``/``off`` to enable/disable the high memory region for PCI MMIO. + The default is ``on``. + gic-version Specify the version of the Generic Interrupt Controller (GIC) to provide. Valid values are: diff --git a/hw/arm/virt.c b/hw/arm/virt.c index 3d1371c05c..0acb71be96 100644 --- a/hw/arm/virt.c +++ b/hw/arm/virt.c @@ -2096,14 +2096,20 @@ static void machvirt_init(MachineState *machine) if (vms->gic_version == VIRT_GIC_VERSION_2) { virt_max_cpus = GIC_NCPU; } else { - virt_max_cpus = virt_redist_capacity(vms, VIRT_GIC_REDIST) + - virt_redist_capacity(vms, VIRT_HIGH_GIC_REDIST2); + virt_max_cpus = virt_redist_capacity(vms, VIRT_GIC_REDIST); + if (vms->highmem_redists) { + virt_max_cpus += virt_redist_capacity(vms, VIRT_HIGH_GIC_REDIST2); + } } if (max_cpus > virt_max_cpus) { error_report("Number of SMP CPUs requested (%d) exceeds max CPUs " "supported by machine 'mach-virt' (%d)", max_cpus, virt_max_cpus); + if (vms->gic_version != VIRT_GIC_VERSION_2 && !vms->highmem_redists) { + error_printf("Try 'highmem-redists=on' for more CPUs\n"); + } + exit(1); } @@ -2372,6 +2378,49 @@ static void virt_set_compact_highmem(Object *obj, bool value, Error **errp) vms->highmem_compact = value; } +static bool virt_get_highmem_redists(Object *obj, Error **errp) +{ + VirtMachineState *vms = VIRT_MACHINE(obj); + + return vms->highmem_redists; +} + +static void virt_set_highmem_redists(Object *obj, bool value, Error **errp) +{ + VirtMachineState *vms = VIRT_MACHINE(obj); + + vms->highmem_redists = value; +} + +static bool virt_get_highmem_ecam(Object *obj, Error **errp) +{ + VirtMachineState *vms = VIRT_MACHINE(obj); + + return vms->highmem_ecam; +} + +static void virt_set_highmem_ecam(Object *obj, bool value, Error **errp) +{ + VirtMachineState *vms = VIRT_MACHINE(obj); + + vms->highmem_ecam = value; +} + +static bool virt_get_highmem_mmio(Object *obj, Error **errp) +{ + VirtMachineState *vms = VIRT_MACHINE(obj); + + return vms->highmem_mmio; +} + +static void virt_set_highmem_mmio(Object *obj, bool value, Error **errp) +{ + VirtMachineState *vms = VIRT_MACHINE(obj); + + vms->highmem_mmio = value; +} + + static bool virt_get_its(Object *obj, Error **errp) { VirtMachineState *vms = VIRT_MACHINE(obj); @@ -2997,6 +3046,28 @@ static void virt_machine_class_init(ObjectClass *oc, void *data) "Set on/off to enable/disable compact " "layout for high memory regions"); + object_class_property_add_bool(oc, "highmem-redists", + virt_get_highmem_redists, + virt_set_highmem_redists); + object_class_property_set_description(oc, "highmem-redists", + "Set on/off to enable/disable high " + "memory region for GICv3 or GICv4 " + "redistributor"); + + object_class_property_add_bool(oc, "highmem-ecam", + virt_get_highmem_ecam, + virt_set_highmem_ecam); + object_class_property_set_description(oc, "highmem-ecam", + "Set on/off to enable/disable high " + "memory region for PCI ECAM"); + + object_class_property_add_bool(oc, "highmem-mmio", + virt_get_highmem_mmio, + virt_set_highmem_mmio); + object_class_property_set_description(oc, "highmem-mmio", + "Set on/off to enable/disable high " + "memory region for PCI MMIO"); + object_class_property_add_str(oc, "gic-version", virt_get_gic_version, virt_set_gic_version); object_class_property_set_description(oc, "gic-version",