[PATCH v2] riscv: dmi: Add SMBIOS/DMI support

[Haibo Xu]

Hi @Palmer,

Could you please let me know whether this patch was OK for the next RISC-V PULL?

Thanks,
Haibo

On Wed, Mar 20, 2024 at 3:46 AM Atish Patra <atishp at rivosinc.com> wrote:
>
> On 3/17/24 19:09, Haibo Xu wrote:
> > Enable the dmi driver for riscv which would allow access the
> > SMBIOS info through some userspace file(/sys/firmware/dmi/*).
> >
> > The change was based on that of arm64 and has been verified
> > by dmidecode tool.
> >
> > Signed-off-by: Haibo Xu <haibo1.xu at intel.com>
> > ---
> > Changes since v1
> >    - Change to use memremap/memunmap for dmi_(early)_remap/unmap
> >      definition(suggested by Ard)
> >    - Minor clean up for comments (Ard)
> > ---
> >   arch/riscv/Kconfig                   | 11 +++++++++++
> >   arch/riscv/include/asm/dmi.h         | 24 ++++++++++++++++++++++++
> >   drivers/firmware/efi/riscv-runtime.c | 13 +++++++++++++
> >   3 files changed, 48 insertions(+)
> >   create mode 100644 arch/riscv/include/asm/dmi.h
> >
> > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> > index 8ebafe337eac..3639151cb4ef 100644
> > --- a/arch/riscv/Kconfig
> > +++ b/arch/riscv/Kconfig
> > @@ -952,6 +952,17 @@ config EFI
> >         allow the kernel to be booted as an EFI application. This
> >         is only useful on systems that have UEFI firmware.
> >
> > +config DMI
> > +     bool "Enable support for SMBIOS (DMI) tables"
> > +     depends on EFI
> > +     default y
> > +     help
> > +       This enables SMBIOS/DMI feature for systems.
> > +
> > +       This option is only useful on systems that have UEFI firmware.
> > +       However, even with this option, the resultant kernel should
> > +       continue to boot on existing non-UEFI platforms.
> > +
> >   config CC_HAVE_STACKPROTECTOR_TLS
> >       def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0)
> >
> > diff --git a/arch/riscv/include/asm/dmi.h b/arch/riscv/include/asm/dmi.h
> > new file mode 100644
> > index 000000000000..ca7cce557ef7
> > --- /dev/null
> > +++ b/arch/riscv/include/asm/dmi.h
> > @@ -0,0 +1,24 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/*
> > + * Copyright (C) 2024 Intel Corporation
> > + *
> > + * based on arch/arm64/include/asm/dmi.h
> > + *
> > + * This file is subject to the terms and conditions of the GNU General Public
> > + * License.  See the file "COPYING" in the main directory of this archive
> > + * for more details.
> > + */
> > +
> > +#ifndef __ASM_DMI_H
> > +#define __ASM_DMI_H
> > +
> > +#include <linux/io.h>
> > +#include <linux/slab.h>
> > +
> > +#define dmi_early_remap(x, l)                memremap(x, l, MEMREMAP_WB)
> > +#define dmi_early_unmap(x, l)                memunmap(x)
> > +#define dmi_remap(x, l)                      memremap(x, l, MEMREMAP_WB)
> > +#define dmi_unmap(x)                 memunmap(x)
> > +#define dmi_alloc(l)                 kzalloc(l, GFP_KERNEL)
> > +
> > +#endif
> > diff --git a/drivers/firmware/efi/riscv-runtime.c b/drivers/firmware/efi/riscv-runtime.c
> > index 09525fb5c240..c3bfb9e77e02 100644
> > --- a/drivers/firmware/efi/riscv-runtime.c
> > +++ b/drivers/firmware/efi/riscv-runtime.c
> > @@ -152,3 +152,16 @@ void arch_efi_call_virt_teardown(void)
> >   {
> >       efi_virtmap_unload();
> >   }
> > +
> > +static int __init riscv_dmi_init(void)
> > +{
> > +     /*
> > +      * On riscv, DMI depends on UEFI, and dmi_setup() needs to
> > +      * be called early because dmi_id_init(), which is an arch_initcall
> > +      * itself, depends on dmi_scan_machine() having been called already.
> > +      */
> > +     dmi_setup();
> > +
> > +     return 0;
> > +}
> > +core_initcall(riscv_dmi_init);
>
> Reviewed-by: Atish Patra <atishp at rivosinc.com>