> On Apr 9, 2025, at 09:53, Ani Sinha <anisi...@redhat.com> wrote:
>
>
>
>> On Feb 7, 2025, at 20:04, David Woodhouse <dw...@infradead.org> wrote:
>>
>> From: David Woodhouse <d...@amazon.co.uk>
>>
>> The vmclock device only has a reset method in order to plug its memory
>> region into the system memory. It was originally done this way in order
>> to defer the memory_region_add_subregion_overlap() from vmclock_realize(),
>> but that doesn't seem to be necessary (any longer?).
>>
>> Still, allowing the platform code to do this is cleaner because it lets
>> the address be specified by the platform, easing the port to Arm and
>> other platforms in future. And the platform has to be involved anyway
>> because of the need to include the device in the ACPI tables (or DT).
>>
>> So drop the reset method and provide a vmclock_mmio_map() function
>> instead, called from pc_machine_done().
>>
>> Shift the ACPI table build into #ifdef CONFIG_ACPI_VMCLOCK too while
>> we're at it, since it looks like that wouldn't have built when vmclock
>> wasn't enabled.
>>
>> Signed-off-by: David Woodhouse <d...@amazon.co.uk>
Reviewed-by: Ani Sinha <anisi...@redhat.com>
>
>> ---
>> hw/acpi/vmclock.c | 18 ++++++------------
>> hw/i386/acpi-build.c | 16 ++++++++++------
>> hw/i386/pc.c | 10 ++++++++++
>> include/hw/acpi/vmclock.h | 1 +
>> 4 files changed, 27 insertions(+), 18 deletions(-)
>>
>> diff --git a/hw/acpi/vmclock.c b/hw/acpi/vmclock.c
>> index 7387e5c9ca..36edfae0ed 100644
>> --- a/hw/acpi/vmclock.c
>> +++ b/hw/acpi/vmclock.c
>> @@ -20,7 +20,6 @@
>> #include "hw/qdev-properties.h"
>> #include "hw/qdev-properties-system.h"
>> #include "migration/vmstate.h"
>> -#include "system/reset.h"
>>
>> #include "standard-headers/linux/vmclock-abi.h"
>>
>> @@ -107,15 +106,14 @@ static const VMStateDescription vmstate_vmclock = {
>> },
>> };
>>
>> -static void vmclock_handle_reset(void *opaque)
>> +void vmclock_mmio_map(Object *dev, hwaddr addr)
>> {
>> - VmclockState *vms = VMCLOCK(opaque);
>> + VmclockState *vms = VMCLOCK(dev);
>>
>> - if (!memory_region_is_mapped(&vms->clk_page)) {
>> - memory_region_add_subregion_overlap(get_system_memory(),
>> - vms->physaddr,
>> - &vms->clk_page, 0);
>> - }
>> + vms->physaddr = addr;
>> + memory_region_add_subregion_overlap(get_system_memory(),
>> + vms->physaddr,
>> + &vms->clk_page, 0);
>> }
>>
>> static void vmclock_realize(DeviceState *dev, Error **errp)
>> @@ -131,8 +129,6 @@ static void vmclock_realize(DeviceState *dev, Error
>> **errp)
>> return;
>> }
>>
>> - vms->physaddr = VMCLOCK_ADDR;
>> -
>> e820_add_entry(vms->physaddr, VMCLOCK_SIZE, E820_RESERVED);
>>
>> memory_region_init_ram(&vms->clk_page, OBJECT(dev), "vmclock_page",
>> @@ -149,8 +145,6 @@ static void vmclock_realize(DeviceState *dev, Error
>> **errp)
>> vms->clk->clock_status = VMCLOCK_STATUS_UNKNOWN;
>> vms->clk->counter_id = VMCLOCK_COUNTER_INVALID;
>>
>> - qemu_register_reset(vmclock_handle_reset, vms);
>> -
>> vmclock_update_guest(vms);
>> }
>>
>> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
>> index 53b7306b43..9db7b1f94e 100644
>> --- a/hw/i386/acpi-build.c
>> +++ b/hw/i386/acpi-build.c
>> @@ -2446,7 +2446,7 @@ void acpi_build(AcpiBuildTables *tables, MachineState
>> *machine)
>> uint8_t *u;
>> GArray *tables_blob = tables->table_data;
>> AcpiSlicOem slic_oem = { .id = NULL, .table_id = NULL };
>> - Object *vmgenid_dev, *vmclock_dev;
>> + Object *vmgenid_dev;
>> char *oem_id;
>> char *oem_table_id;
>>
>> @@ -2519,12 +2519,16 @@ void acpi_build(AcpiBuildTables *tables,
>> MachineState *machine)
>> tables->vmgenid, tables->linker, x86ms->oem_id);
>> }
>>
>> - vmclock_dev = find_vmclock_dev();
>> - if (vmclock_dev) {
>> - acpi_add_table(table_offsets, tables_blob);
>> - vmclock_build_acpi(VMCLOCK(vmclock_dev), tables_blob,
>> tables->linker,
>> - x86ms->oem_id);
>> +#ifdef CONFIG_ACPI_VMCLOCK
>> + {
>> + Object *vmclock_dev = find_vmclock_dev();
>> + if (vmclock_dev) {
>> + acpi_add_table(table_offsets, tables_blob);
>> + vmclock_build_acpi(VMCLOCK(vmclock_dev), tables_blob,
>> tables->linker,
>> + x86ms->oem_id);
>> + }
>> }
>> +#endif
>>
>> if (misc.has_hpet) {
>> acpi_add_table(table_offsets, tables_blob);
>> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
>> index b46975c8a4..776c2c8a37 100644
>> --- a/hw/i386/pc.c
>> +++ b/hw/i386/pc.c
>> @@ -60,6 +60,7 @@
>> #include "hw/i386/kvm/xen_gnttab.h"
>> #include "hw/i386/kvm/xen_xenstore.h"
>> #include "hw/mem/memory-device.h"
>> +#include "hw/acpi/vmclock.h"
>> #include "e820_memory_layout.h"
>> #include "trace.h"
>> #include "sev.h"
>> @@ -635,6 +636,15 @@ void pc_machine_done(Notifier *notifier, void *data)
>> pci_bus_add_fw_cfg_extra_pci_roots(x86ms->fw_cfg, pcms->pcibus,
>> &error_abort);
>>
>> +#ifdef CONFIG_ACPI_VMCLOCK
>> + {
>> + Object *vmclock = find_vmclock_dev();
>> + if (vmclock) {
>> + vmclock_mmio_map(vmclock, VMCLOCK_ADDR);
>> + }
>> + }
>> +#endif
>> +
>> acpi_setup();
>> if (x86ms->fw_cfg) {
>> fw_cfg_build_smbios(pcms, x86ms->fw_cfg,
>> pcms->smbios_entry_point_type);
>> diff --git a/include/hw/acpi/vmclock.h b/include/hw/acpi/vmclock.h
>> index 5605605812..97f8a30c0e 100644
>> --- a/include/hw/acpi/vmclock.h
>> +++ b/include/hw/acpi/vmclock.h
>> @@ -30,5 +30,6 @@ static inline Object *find_vmclock_dev(void)
>>
>> void vmclock_build_acpi(VmclockState *vms, GArray *table_data,
>> BIOSLinker *linker, const char *oem_id);
>> +void vmclock_mmio_map(Object *dev, hwaddr addr);
>>
>> #endif
>> --
>> 2.48.1
