Re: [QEMU PATCH v2 3/6] acpi/nvdimm: NVDIMM _DSM Spec supports revision 2

[Igor Mammedov <imammedo@redhat.com>]

On Mon, 30 May 2022 11:40:44 +0800
Robert Hoo <robert.hu@linux.intel.com> wrote:

> The Intel Optane PMem DSM Interface, Version 2.0 [1], is the up-to-date
> spec for NVDIMM _DSM definition, which supports revision_id == 2.
> 
> Nevertheless, Rev.2 of NVDIMM _DSM has no functional change on those Label
> Data _DSM Functions, which are the only ones implemented for vNVDIMM.
> So, simple change to support this revision_id == 2 case.
> 
> [1] https://pmem.io/documents/IntelOptanePMem_DSM_Interface-V2.0.pdf

pls enumerate functions that QEMU implement and that are supported by rev=2,
do we really need rev2 ?

also don't we need make sure that rev1 only function are excluded?
/spec above says, functions 3-6 are deprecated and limited to rev1 only/
"
Warning: This function has been deprecated in preference to the ACPI 6.2 _LSW (Label Storage Write)
NVDIMM Device Interface and is only supported with Arg1 – Revision Id = 1. It is included here for
backwards compatibility with existing Arg1 - Revision Id = 1 implementations.
"

> 
> Signed-off-by: Robert Hoo <robert.hu@linux.intel.com>
> Reviewed-by: Jingqi Liu <jingqi.liu@intel.com>
> ---
>  hw/acpi/nvdimm.c | 10 +++++++---
>  1 file changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/hw/acpi/nvdimm.c b/hw/acpi/nvdimm.c
> index 0ab247a870..59b42afcf1 100644
> --- a/hw/acpi/nvdimm.c
> +++ b/hw/acpi/nvdimm.c
> @@ -849,9 +849,13 @@ nvdimm_dsm_write(void *opaque, hwaddr addr, uint64_t val, unsigned size)
>      nvdimm_debug("Revision 0x%x Handler 0x%x Function 0x%x.\n", in->revision,
>                   in->handle, in->function);
>  
> -    if (in->revision != 0x1 /* Currently we only support DSM Spec Rev1. */) {
> -        nvdimm_debug("Revision 0x%x is not supported, expect 0x%x.\n",
> -                     in->revision, 0x1);
> +    /*
> +     * Current NVDIMM _DSM Spec supports Rev1 and Rev2
> +     * Intel® OptanePersistent Memory Module DSM Interface, Revision 2.0
> +     */
> +    if (in->revision != 0x1 && in->revision != 0x2) {
> +        nvdimm_debug("Revision 0x%x is not supported, expect 0x1 or 0x2.\n",
> +                     in->revision);
>          nvdimm_dsm_no_payload(NVDIMM_DSM_RET_STATUS_UNSUPPORT, dsm_mem_addr);
>          goto exit;
>      }