On Wed, May 28, 2025 at 06:53:38PM +0800, Li Chen wrote:
> From: Li Chen <chenl...@chinatelecom.cn>
>
> The virt machines always instantiate a PL011/16550 at UART0 and
> describe it in ACPI (DSDT device node plus optional SPCR table). When
> the command line contains “-serial none” there is no backend attached to
> that UART, yet the guest still discovers it via ACPI and may try to use
> it as a console, causing unexpected results.
>
> And also explicitly add "-serial stdio" in bios-tables-test.c to allow
> serial device creation, otherwise DSDT assert would get failure because
> "-nodefaults" will not create uart device by default:
>
> ```
> stderr:
> acpi-test: Warning! DSDT binary file mismatch. Actual [aml:/tmp/aml-BMOL72],
> Expected [aml:tests/data/acpi/aarch64/virt/DSDT].
> See source file tests/qtest/bios-tables-test.c for instructions on how to
> update expected files.
> acpi-test: Warning! DSDT mismatch. Actual [asl:/tmp/asl-RNOL72.dsl,
> aml:/tmp/aml-BMOL72], Expected [asl:/tmp/asl-ZVQL72.dsl,
> aml:tests/data/acpi/aarch64/virt/DS
> DT].
> ```
>
> Suggested-by: Philippe Mathieu-Daudé <phi...@linaro.org>
> Signed-off-by: Li Chen <chenl...@chinatelecom.cn>
> Reviewed-by: Sunil V L <suni...@ventanamicro.com>
will need to be rebased updating loongarch too, now.
> ---
>
> Notes:
> Changes since v3: 1. Add Reviewed-by from Sunil V L
> <suni...@ventanamicro.com>
> 2. Explicitly add "-serial stdio" to pass DSDT assert
>
> hw/arm/virt-acpi-build.c | 15 +++++++++------
> hw/riscv/virt-acpi-build.c | 7 +++++--
> include/system/system.h | 2 ++
> system/vl.c | 5 +++++
> tests/qtest/bios-tables-test.c | 5 +++--
> 5 files changed, 24 insertions(+), 10 deletions(-)
>
> diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
> index d77d16cbd3..c26aedb1b1 100644
> --- a/hw/arm/virt-acpi-build.c
> +++ b/hw/arm/virt-acpi-build.c
> @@ -59,6 +59,7 @@
> #include "hw/acpi/viot.h"
> #include "hw/virtio/virtio-acpi.h"
> #include "target/arm/multiprocessing.h"
> +#include "system/system.h"
>
> #define ARM_SPI_BASE 32
>
> @@ -821,11 +822,13 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
> VirtMachineState *vms)
> */
> scope = aml_scope("\\_SB");
> acpi_dsdt_add_cpus(scope, vms);
> - acpi_dsdt_add_uart(scope, &memmap[VIRT_UART0],
> - (irqmap[VIRT_UART0] + ARM_SPI_BASE), 0);
> - if (vms->second_ns_uart_present) {
> - acpi_dsdt_add_uart(scope, &memmap[VIRT_UART1],
> - (irqmap[VIRT_UART1] + ARM_SPI_BASE), 1);
> + if (serial_exist()) {
> + acpi_dsdt_add_uart(scope, &memmap[VIRT_UART0],
> + (irqmap[VIRT_UART0] + ARM_SPI_BASE), 0);
> + if (vms->second_ns_uart_present) {
> + acpi_dsdt_add_uart(scope, &memmap[VIRT_UART1],
> + (irqmap[VIRT_UART1] + ARM_SPI_BASE), 1);
> + }
> }
> if (vmc->acpi_expose_flash) {
> acpi_dsdt_add_flash(scope, &memmap[VIRT_FLASH]);
> @@ -937,7 +940,7 @@ void virt_acpi_build(VirtMachineState *vms,
> AcpiBuildTables *tables)
>
> acpi_add_table(table_offsets, tables_blob);
>
> - if (ms->acpi_spcr_enabled) {
> + if (ms->acpi_spcr_enabled && serial_exist()) {
> spcr_setup(tables_blob, tables->linker, vms);
> }
>
> diff --git a/hw/riscv/virt-acpi-build.c b/hw/riscv/virt-acpi-build.c
> index ee1416d264..80bf3c3cec 100644
> --- a/hw/riscv/virt-acpi-build.c
> +++ b/hw/riscv/virt-acpi-build.c
> @@ -39,6 +39,7 @@
> #include "qapi/error.h"
> #include "qemu/error-report.h"
> #include "system/reset.h"
> +#include "system/system.h"
>
> #define ACPI_BUILD_TABLE_SIZE 0x20000
> #define ACPI_BUILD_INTC_ID(socket, index) ((socket << 24) | (index))
> @@ -474,7 +475,9 @@ static void build_dsdt(GArray *table_data,
> memmap[VIRT_APLIC_S].size, "RSCV0002");
> }
>
> - acpi_dsdt_add_uart(scope, &memmap[VIRT_UART0], UART0_IRQ);
> + if (serial_exist())
> + acpi_dsdt_add_uart(scope, &memmap[VIRT_UART0], UART0_IRQ);
> +
coding style violation
> if (virt_is_iommu_sys_enabled(s)) {
> acpi_dsdt_add_iommu_sys(scope, &memmap[VIRT_IOMMU_SYS],
> IOMMU_SYS_IRQ);
> }
> @@ -895,7 +898,7 @@ static void virt_acpi_build(RISCVVirtState *s,
> AcpiBuildTables *tables)
>
> acpi_add_table(table_offsets, tables_blob);
>
> - if (ms->acpi_spcr_enabled) {
> + if (ms->acpi_spcr_enabled && serial_exist()) {
> spcr_setup(tables_blob, tables->linker, s);
> }
>
> diff --git a/include/system/system.h b/include/system/system.h
> index a7effe7dfd..ca1af38432 100644
> --- a/include/system/system.h
> +++ b/include/system/system.h
> @@ -75,6 +75,8 @@ extern unsigned int nb_prom_envs;
> /* Return the Chardev for serial port i, or NULL if none */
> Chardev *serial_hd(int i);
>
> +bool serial_exist(void);
> +
> /* parallel ports */
>
> #define MAX_PARALLEL_PORTS 3
> diff --git a/system/vl.c b/system/vl.c
> index fd402b8ff8..e340ee3a95 100644
> --- a/system/vl.c
> +++ b/system/vl.c
> @@ -1485,6 +1485,11 @@ Chardev *serial_hd(int i)
> return NULL;
> }
>
> +bool serial_exist(void)
> +{
> + return serial_hd(0) ? true : false;
> +}
> +
serial_exists
> static bool parallel_parse(const char *devname, Error **errp)
> {
> static int index = 0;
> diff --git a/tests/qtest/bios-tables-test.c b/tests/qtest/bios-tables-test.c
> index 44de152a36..452566fa86 100644
> --- a/tests/qtest/bios-tables-test.c
> +++ b/tests/qtest/bios-tables-test.c
> @@ -824,10 +824,11 @@ static char *test_acpi_create_args(test_data *data,
> const char *params)
> /*
> * TODO: convert '-drive if=pflash' to new syntax (see e33763be7cd3)
> * when arm/virt boad starts to support it.
> + * NOTE: Explicitly add "-serial stdio" to enable uart in DSDT.
> */
> if (data->cd) {
> args = g_strdup_printf("-machine %s%s %s -accel tcg "
> - "-nodefaults -nographic "
> + "-nodefaults -serial stdio -nographic "
> "-drive if=pflash,format=raw,file=%s,readonly=on "
> "-drive if=pflash,format=raw,file=%s,snapshot=on -cdrom %s
> %s",
> data->machine, data->machine_param ?: "",
> @@ -835,7 +836,7 @@ static char *test_acpi_create_args(test_data *data, const
> char *params)
> data->uefi_fl1, data->uefi_fl2, data->cd, params ? params :
> "");
> } else {
> args = g_strdup_printf("-machine %s%s %s -accel tcg "
> - "-nodefaults -nographic "
> + "-nodefaults -serial stdio -nographic "
> "-drive if=pflash,format=raw,file=%s,readonly=on "
> "-drive if=pflash,format=raw,file=%s,snapshot=on %s",
> data->machine, data->machine_param ?: "",
> --
> 2.49.0
