> -----Original Message-----
> From: Michael S. Tsirkin <m...@redhat.com>
> Sent: Monday, May 13, 2024 2:31 PM
> To: JeeHeng Sia <jeeheng....@starfivetech.com>
> Cc: qemu-...@nongnu.org; qemu-devel@nongnu.org; qemu-ri...@nongnu.org;
> imamm...@redhat.com; anisi...@redhat.com;
> peter.mayd...@linaro.org; shannon.zha...@gmail.com; suni...@ventanamicro.com;
> pal...@dabbelt.com; alistair.fran...@wdc.com;
> bin.m...@windriver.com; liwei1...@gmail.com; dbarb...@ventanamicro.com;
> zhiwei_...@linux.alibaba.com
> Subject: Re: [PATCH v2 2/3] hw/acpi: Upgrade ACPI SPCR table to support SPCR
> table version 4 format
>
> On Mon, May 06, 2024 at 10:22:11PM -0700, Sia Jee Heng wrote:
> > Update the SPCR table to accommodate the SPCR Table version 4 [1].
> > The SPCR table has been modified to adhere to the version 4 format [2].
> >
> > [1]:
> > https://learn.microsoft.com/en-us/windows-hardware/drivers/serports/serial-port-console-redirection-table
> > [2]: https://github.com/acpica/acpica/pull/931
> >
> > Signed-off-by: Sia Jee Heng <jeeheng....@starfivetech.com>
>
> What does this achieve? We don't normally change unless it gets
> us some useful feature.
The changes in Table 4 primarily include the addition of RISC-V support
and modifications to the Interrupt Type field. Additionally, new fields
added are Precise Baud Rate, NamespaceStringLength, NamespaceStringOffset,
and NamespaceString[].
>
>
> > ---
> > hw/acpi/aml-build.c | 14 +++++++++++---
> > hw/arm/virt-acpi-build.c | 10 ++++++++--
> > hw/riscv/virt-acpi-build.c | 12 +++++++++---
> > include/hw/acpi/acpi-defs.h | 7 +++++--
> > include/hw/acpi/aml-build.h | 2 +-
> > 5 files changed, 34 insertions(+), 11 deletions(-)
> >
> > diff --git a/hw/acpi/aml-build.c b/hw/acpi/aml-build.c
> > index 6d4517cfbe..7c43573eef 100644
> > --- a/hw/acpi/aml-build.c
> > +++ b/hw/acpi/aml-build.c
> > @@ -1996,7 +1996,7 @@ static void build_processor_hierarchy_node(GArray
> > *tbl, uint32_t flags,
> >
> > void build_spcr(GArray *table_data, BIOSLinker *linker,
> > const AcpiSpcrData *f, const uint8_t rev,
> > - const char *oem_id, const char *oem_table_id)
> > + const char *oem_id, const char *oem_table_id, const char
> > *name)
> > {
> > AcpiTable table = { .sig = "SPCR", .rev = rev, .oem_id = oem_id,
> > .oem_table_id = oem_table_id };
> > @@ -2042,8 +2042,16 @@ void build_spcr(GArray *table_data, BIOSLinker
> > *linker,
> > build_append_int_noprefix(table_data, f->pci_flags, 4);
> > /* PCI Segment */
> > build_append_int_noprefix(table_data, f->pci_segment, 1);
> > - /* Reserved */
> > - build_append_int_noprefix(table_data, 0, 4);
> > + /* UartClkFreq */
> > + build_append_int_noprefix(table_data, f->uart_clk_freq, 4);
> > + /* PreciseBaudrate */
> > + build_append_int_noprefix(table_data, f->precise_baudrate, 4);
> > + /* NameSpaceStringLength */
> > + build_append_int_noprefix(table_data, f->namespace_string_length, 2);
> > + /* NameSpaceStringOffset */
> > + build_append_int_noprefix(table_data, f->namespace_string_offset, 2);
> > + /* NamespaceString[] */
> > + g_array_append_vals(table_data, name, f->namespace_string_length);
> >
> > acpi_table_end(linker, &table);
> > }
> > diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
> > index 6a1bde61ce..cb345e8659 100644
> > --- a/hw/arm/virt-acpi-build.c
> > +++ b/hw/arm/virt-acpi-build.c
> > @@ -428,11 +428,12 @@ build_iort(GArray *table_data, BIOSLinker *linker,
> > VirtMachineState *vms)
> >
> > /*
> > * Serial Port Console Redirection Table (SPCR)
> > - * Rev: 1.07
> > + * Rev: 1.10
> > */
> > static void
> > spcr_setup(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
> > {
> > + const char name[] = ".";
> > AcpiSpcrData serial = {
> > .interface_type = 3, /* ARM PL011 UART */
> > .base_addr.id = AML_AS_SYSTEM_MEMORY,
> > @@ -456,9 +457,14 @@ spcr_setup(GArray *table_data, BIOSLinker *linker,
> > VirtMachineState *vms)
> > .pci_function = 0,
> > .pci_flags = 0,
> > .pci_segment = 0,
> > + .uart_clk_freq = 0,
> > + .precise_baudrate = 0,
> > + .namespace_string_length = sizeof(name),
> > + .namespace_string_offset = 88,
> > };
> >
> > - build_spcr(table_data, linker, &serial, 2, vms->oem_id,
> > vms->oem_table_id);
> > + build_spcr(table_data, linker, &serial, 4, vms->oem_id,
> > vms->oem_table_id,
> > + name);
> > }
> >
> > /*
> > diff --git a/hw/riscv/virt-acpi-build.c b/hw/riscv/virt-acpi-build.c
> > index 0925528160..5fa3942491 100644
> > --- a/hw/riscv/virt-acpi-build.c
> > +++ b/hw/riscv/virt-acpi-build.c
> > @@ -176,14 +176,15 @@ acpi_dsdt_add_uart(Aml *scope, const MemMapEntry
> > *uart_memmap,
> >
> > /*
> > * Serial Port Console Redirection Table (SPCR)
> > - * Rev: 1.07
> > + * Rev: 1.10
> > */
> >
> > static void
> > spcr_setup(GArray *table_data, BIOSLinker *linker, RISCVVirtState *s)
> > {
> > + const char name[] = ".";
> > AcpiSpcrData serial = {
> > - .interface_type = 0, /* 16550 compatible */
> > + .interface_type = 0x12, /* 16550 compatible */
> > .base_addr.id = AML_AS_SYSTEM_MEMORY,
> > .base_addr.width = 32,
> > .base_addr.offset = 0,
> > @@ -205,9 +206,14 @@ spcr_setup(GArray *table_data, BIOSLinker *linker,
> > RISCVVirtState *s)
> > .pci_function = 0,
> > .pci_flags = 0,
> > .pci_segment = 0,
> > + .uart_clk_freq = 0,
> > + .precise_baudrate = 0,
> > + .namespace_string_length = sizeof(name),
> > + .namespace_string_offset = 88,
> > };
> >
> > - build_spcr(table_data, linker, &serial, 2, s->oem_id, s->oem_table_id);
> > + build_spcr(table_data, linker, &serial, 4, s->oem_id, s->oem_table_id,
> > + name);
> > }
> >
> > /* RHCT Node[N] starts at offset 56 */
> > diff --git a/include/hw/acpi/acpi-defs.h b/include/hw/acpi/acpi-defs.h
> > index 0e6e82b339..2e6e341998 100644
> > --- a/include/hw/acpi/acpi-defs.h
> > +++ b/include/hw/acpi/acpi-defs.h
> > @@ -112,7 +112,6 @@ typedef struct AcpiSpcrData {
> > uint8_t flow_control;
> > uint8_t terminal_type;
> > uint8_t language;
> > - uint8_t reserved1;
> > uint16_t pci_device_id; /* Must be 0xffff if not PCI device */
> > uint16_t pci_vendor_id; /* Must be 0xffff if not PCI device */
> > uint8_t pci_bus;
> > @@ -120,7 +119,11 @@ typedef struct AcpiSpcrData {
> > uint8_t pci_function;
> > uint32_t pci_flags;
> > uint8_t pci_segment;
> > - uint32_t reserved2;
> > + uint32_t uart_clk_freq;
> > + uint32_t precise_baudrate;
> > + uint32_t namespace_string_length;
> > + uint32_t namespace_string_offset;
> > + char namespace_string[];
> > } AcpiSpcrData;
> >
> > #define ACPI_FADT_ARM_PSCI_COMPLIANT (1 << 0)
> > diff --git a/include/hw/acpi/aml-build.h b/include/hw/acpi/aml-build.h
> > index a3784155cb..68c0f2dbee 100644
> > --- a/include/hw/acpi/aml-build.h
> > +++ b/include/hw/acpi/aml-build.h
> > @@ -500,5 +500,5 @@ void build_tpm2(GArray *table_data, BIOSLinker *linker,
> > GArray *tcpalog,
> >
> > void build_spcr(GArray *table_data, BIOSLinker *linker,
> > const AcpiSpcrData *f, const uint8_t rev,
> > - const char *oem_id, const char *oem_table_id);
> > + const char *oem_id, const char *oem_table_id, const char
> > *name);
> > #endif
> > --
> > 2.34.1