On Fri, Nov 16, 2018 at 09:45:42AM +0800, peng.h...@zte.com.cn wrote: > >> add pvpanic device in virt acpi table, so when kenrel command line uses > >> acpi=force, kernel can get info from acpi table in aarch64. > > [...] > > >> > >> +static void acpi_dsdt_add_pvpanic(Aml *scope, const MemMapEntry > >> *pvpanic_memmap) > >> +{ > >> + Aml *dev = aml_device("PANC"); > > > >Shouldn't this be "PEVT" ("panic event"), like it is for x86? > > > yeah, I will change it. > >> + aml_append(dev, aml_name_decl("_HID", aml_string("QEMU0001"))); > >> + aml_append(dev, aml_name_decl("_UID", aml_int(0))); > > > >Why add _UID? Also, I see x86 had some issues with not having _STA and > >then having a _STA without the UI flag. It now has _STA=0xf > >(PRESENT|ENABLED|UI|FUNCTIONING). I'm not saying we need to do that to, > >but I'd like to know if it was considered and decided we don't need to. > > > The way the kernel code processes _STA is that if _STA is not found, the > default > setting is (PRESENT|ENABLED|UI|FUNCTIONING). So I think it is not necessary > to add it. It is only parsed in the pvpanic driver.
Good enough for me. > for _UID, I think it is used for device index. I just fill it with 0 because > there is > only one pvpanic device. OK, but I'm still not sure it's necessary. > > by the way, How to get the value of ACPI conveniently? how dou you get the > value of _STA? Not sure what you mean here. From where do you want to check the value? If you mean from guest userspace, then there's nothing convenient that I know of. You'll have to disassemble the tables you extract from sysfs, afaik. Thanks, drew > > Thanks. > >> + > >> + Aml *crs = aml_resource_template(); > >> + aml_append(crs, aml_memory32_fixed(pvpanic_memmap->base, > >> + pvpanic_memmap->size, > >> AML_READ_WRITE)); > >> + > >> + aml_append(dev, aml_name_decl("_CRS", crs)); > >> + > >> + aml_append(scope, dev); > >> +} > >> + > >> static void acpi_dsdt_add_uart(Aml *scope, const MemMapEntry *uart_memmap, > >> uint32_t uart_irq) > >> { > >> @@ -770,6 +785,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker, > >> VirtMachineState *vms) > >> acpi_dsdt_add_cpus(scope, vms->smp_cpus); > >> acpi_dsdt_add_uart(scope, &memmap[VIRT_UART], > >> (irqmap[VIRT_UART] + ARM_SPI_BASE)); > >> + acpi_dsdt_add_pvpanic(scope, &memmap[VIRT_PVPANIC]); > >> acpi_dsdt_add_flash(scope, &memmap[VIRT_FLASH]); > >> acpi_dsdt_add_fw_cfg(scope, &memmap[VIRT_FW_CFG]); > >> acpi_dsdt_add_virtio(scope, &memmap[VIRT_MMIO], > >> -- > >> 1.8.3.1 > >> > >> > > > >Thanks, > >drew