The ACPI SPCR (Serial Port Console Redirection) table allows firmware
to specify a preferred serial console device to the operating system.
On ARM64 systems, Linux by default respects this table: even if the
kernel command line does not include a hardware serial console (e.g.,
"console=ttyAMA0"), the kernel still register the serial device
referenced by SPCR as a printk console.
While this behavior is standard-compliant, it can lead to situations
where guest console behavior is influenced by platform firmware rather
than user-specified configuration. To make guest console behavior more
predictable and under user control, this patch introduces a machine
option to explicitly disable SPCR table exposure:
-machine spcr=off
By default, the option is enabled (spcr=on), preserving existing
behavior. When disabled, QEMU will omit the SPCR table from the guest's
ACPI namespace, ensuring that only consoles explicitly declared in the
kernel command line are registered.
Signed-off-by: Li Chen <chenl311@chinatelecom.cn>
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Sunil V L <sunilvl@ventanamicro.com>
Message-Id: <20250528105404.457729-2-me@linux.beauty>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
With API build_mcfg(), it is not necessary with parameter structure
AcpiMcfgInfo to convert to little endian since it is directly used
with host native endian.
Here remove endian conversion before calling function build_mcfg().
With this patch, bios-tables-test passes to run on big endian host
machine S390.
Fixes: 735143f10d ("hw/loongarch: Add acpi ged support")
Cc: qemu-stable@nongnu.org
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Reviewed-by: Song Gao <gaosong@loongson.cn>
Message-Id: <20250604065502.1114098-2-maobibo@loongson.cn>
Signed-off-by: Song Gao <gaosong@loongson.cn>
XSDT table is introduced in ACPI Specification 5.0, it supports 64-bit
address in the table. There is LoongArch system support from ACPI
Specification 6.4 and later, XSDT is supported by LoongArch system.
Here replace RSDT with XSDT table.
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Reviewed-by: Song Gao <gaosong@loongson.cn>
On LoongArch virt machine, ACPI GED hardware is used for CPU hotplug
handler, here CPU hotplug support feature is added based on GED handler,
also CPU scan and reject method is added about CPU device in DSDT table.
Co-developed-by: Xianglai Li <lixianglai@loongson.cn>
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Replace function prefix name loongarch_xxx with virt_xxx in file
virt-acpi-build.c
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
File acpi-build.c is relative with virt machine type, rename it with
virt-acpi-build.c
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
