Re: [PATCH v2 3/4] target/riscv: SMBIOS support for RISC-V virt machine

[Heinrich Schuchardt]

On 22.01.24 10:57, Andrew Jones wrote:
> On Fri, Dec 29, 2023 at 01:07:23PM +0100, Heinrich Schuchardt wrote:
> > Generate SMBIOS tables for the RISC-V mach-virt.
> > Add CONFIG_SMBIOS=y to the RISC-V default config.
> > Set the default processor family in the type 4 table.
> >
> > The implementation is based on the corresponding ARM and Loongson code.
> >
> > With the patch the following firmware tables are provided:
> >
> >      etc/smbios/smbios-anchor
> >      etc/smbios/smbios-tables
> >
> > Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
> > ---
> > v2:
> >         set processor family
> > ---
> >   hw/riscv/Kconfig |  1 +
> >   hw/riscv/virt.c  | 42 ++++++++++++++++++++++++++++++++++++++++++
> >   2 files changed, 43 insertions(+)
> >
> > diff --git a/hw/riscv/Kconfig b/hw/riscv/Kconfig
> > index b6a5eb4452..1e11ac9432 100644
> > --- a/hw/riscv/Kconfig
> > +++ b/hw/riscv/Kconfig
> > @@ -41,6 +41,7 @@ config RISCV_VIRT
> >       select RISCV_IMSIC
> >       select SIFIVE_PLIC
> >       select SIFIVE_TEST
> > +    select SMBIOS
> >       select VIRTIO_MMIO
> >       select FW_CFG_DMA
> >       select PLATFORM_BUS
> > diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
> > index d2eac24156..a876dd8f34 100644
> > --- a/hw/riscv/virt.c
> > +++ b/hw/riscv/virt.c
> > @@ -36,6 +36,7 @@
> >   #include "hw/riscv/boot.h"
> >   #include "hw/riscv/numa.h"
> >   #include "kvm/kvm_riscv.h"
> > +#include "hw/firmware/smbios.h"
> >   #include "hw/intc/riscv_aclint.h"
> >   #include "hw/intc/riscv_aplic.h"
> >   #include "hw/intc/riscv_imsic.h"
> > @@ -1249,6 +1250,45 @@ static void create_platform_bus(RISCVVirtState *s, 
> > DeviceState *irqchip)
> >                                   sysbus_mmio_get_region(sysbus, 0));
> >   }
> >   
> > +static void virt_build_smbios(RISCVVirtState *s)
> > +{
> > +    MachineClass *mc = MACHINE_GET_CLASS(s);
> > +    MachineState *ms = MACHINE(s);
> > +    uint8_t *smbios_tables, *smbios_anchor;
> > +    size_t smbios_tables_len, smbios_anchor_len;
> > +    struct smbios_phys_mem_area mem_array;
> > +    const char *product = "QEMU Virtual Machine";
> > +
> > +    if (kvm_enabled()) {
> > +        product = "KVM Virtual Machine";
> > +    }
> > +
> > +    smbios_set_defaults("QEMU", product, mc->name, false,
> > +                        true, SMBIOS_ENTRY_POINT_TYPE_64);
> > +
> > +#if defined(TARGET_RISCV32)
> > +    smbios_set_default_processor_family(0x200);
> > +#elif defined(TARGET_RISCV64)
> > +    smbios_set_default_processor_family(0x201);
> > +#endif
>
> I think we should use misa_mxl_max to determine the family, rather than
> TARGET_*, because, iirc, we're slowly working our ways towards allowing
> rv32 cpus to be instantiated with qemu-system-riscv64.

Hello Andrew,

thank you for reviewing. I guess you mean something like:

    if (riscv_is_32bit(&s->soc[0])) {
        smbios_set_default_processor_family(0x200);
#if defined(TARGET_RISCV64)
    } else {
        smbios_set_default_processor_family(0x201);
#endif
    }

riscv_is_32bit returns harts->harts[0].env.misa_mxl_max == MXL_RV32.

Some real hardware has a 32bit hart and multiple 64bit harts. Will QEMU 
support mixing harts with different bitness on the virt machine in 
future? In that case we would have to revisit the code using 
misa_mxl_max in multiple places.

Best regards

Heinrich

> > +
> > +    /* build the array of physical mem area from base_memmap */
> > +    mem_array.address = s->memmap[VIRT_DRAM].base;
> > +    mem_array.length = ms->ram_size;
> > +
> > +    smbios_get_tables(ms, &mem_array, 1,
> > +                      &smbios_tables, &smbios_tables_len,
> > +                      &smbios_anchor, &smbios_anchor_len,
> > +                      &error_fatal);
> > +
> > +    if (smbios_anchor) {
> > +        fw_cfg_add_file(s->fw_cfg, "etc/smbios/smbios-tables",
> > +                        smbios_tables, smbios_tables_len);
> > +        fw_cfg_add_file(s->fw_cfg, "etc/smbios/smbios-anchor",
> > +                        smbios_anchor, smbios_anchor_len);
> > +    }
> > +}
> > +
> >   static void virt_machine_done(Notifier *notifier, void *data)
> >   {
> >       RISCVVirtState *s = container_of(notifier, RISCVVirtState,
> > @@ -1337,6 +1377,8 @@ static void virt_machine_done(Notifier *notifier, void 
> > *data)
> >           riscv_setup_direct_kernel(kernel_entry, fdt_load_addr);
> >       }
> >   
> > +    virt_build_smbios(s);
> > +
> >       if (virt_is_acpi_enabled(s)) {
> >           virt_acpi_setup(s);
> >       }
> > --
> > 2.43.0
>
> Otherwise,
>
> Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
>
> Thanks,
> drew