[v3,0/2] hw/mem: CXL Type-3 Volatile Memory Support

Message

Jonathan Cameron Feb. 21, 2023, 2 p.m. UTC

v3: Noticed whilst chasing an unrelated kernel bug.
 - Drop setting of DVSEC range base addresses.  Whilst harmless,
   expectation is that this will be 0 until the OS sets it (or uses
   HDM decoders instead)

Based on following series (in order)
1. [PATCH v4 00/10] hw/cxl: CXL emulation cleanups and minor fixes for upstream
2. [PATCH v4 0/8] hw/cxl: RAS error emulation and injection
3. [PATCH 0/2] hw/cxl: Passthrough HDM decoder emulation

Based on: Message-Id: [e-mail]
Based-on: Message-id: [e-mail]
Based-on: Message-id: [e-mail]

Kernel code is queued up in kernel.org cxl/next for the merge window
that just opened.

Now we have some kernel code to test this against (and it looks good)
I'd like to propose this series for upstream following 3 other series
already proposed for inclusion:

Original cover letter with minor updates.

This patches provides 2 features to the CXL Type-3 Device:
    1) Volatile Memory Region Support
    2) Multi-Region support (1 Volatile, 1 Persistent)

Summary of Changes per-commit:
1) Whitespace updates to docs and tests
2) Refactor CDAT DSMAS Initialization for multi-region initialization
   Multi-Region and Volatile Memory support for CXL Type-3 Devices
   Test and Documentation updates

The final patch in this series makes 6 major changes to the type-3
device in order to implement multi-region and volatile region support
    1) The HostMemoryBackend [hostmem] has been replaced by two
       [hostvmem] and [hostpmem] to store volatile and persistent memory
       respectively
    2) The single AddressSpace has been replaced by two AddressSpaces
       [hostvmem_as] and [hostpmem_as] to map respective memdevs.
    3) Each memory region size and total region are stored separately
    4) The CDAT and DVSEC memory map entries have been updated:
       a) if vmem is present, vmem is mapped at DPA(0)
       b) if pmem is present
          i)  and vmem is present, pmem is mapped at DPA(vmem->size)
          ii) else, pmem is mapped at DPA(0)
       c) partitioning of pmem is not supported in this patch set but
          has been discussed and this design should suffice.
    5) Read/Write functions have been updated to access AddressSpaces
       according to the mapping described in #4.  Access to the
       persistent address space is calculated by (dpa-vmem_len)
    6) cxl-mailbox has been updated to report the respective size of
       volatile and persistent memory region


Gregory Price (2):
  tests/qtest/cxl-test: whitespace, line ending cleanup
  hw/cxl: Multi-Region CXL Type-3 Devices (Volatile and Persistent)

 docs/system/devices/cxl.rst    |  49 ++++--
 hw/cxl/cxl-mailbox-utils.c     |  26 +--
 hw/mem/cxl_type3.c             | 294 +++++++++++++++++++++++++--------
 include/hw/cxl/cxl_device.h    |  11 +-
 tests/qtest/bios-tables-test.c |   8 +-
 tests/qtest/cxl-test.c         | 146 +++++++++++-----
 6 files changed, 392 insertions(+), 142 deletions(-)

Comments

Jonathan Cameron Feb. 21, 2023, 3:32 p.m. UTC | #1

On Tue, 21 Feb 2023 14:00:21 +0000
Jonathan Cameron <[e-mail]> wrote:

> v3: Noticed whilst chasing an unrelated kernel bug.
>  - Drop setting of DVSEC range base addresses.  Whilst harmless,
>    expectation is that this will be 0 until the OS sets it (or uses
>    HDM decoders instead)
> 
> Based on following series (in order)
> 1. [PATCH v4 00/10] hw/cxl: CXL emulation cleanups and minor fixes for upstream
> 2. [PATCH v4 0/8] hw/cxl: RAS error emulation and injection

I sent these in the wrong order. Now v5 (comment change and some tags)
Other series unchanged.

> 3. [PATCH 0/2] hw/cxl: Passthrough HDM decoder emulation
> 
> Based on: Message-Id: [e-mail]
> Based-on: Message-id: [e-mail]

Based-on: Message-id: [e-mail]

> Based-on: Message-id: [e-mail]
> 
> Kernel code is queued up in kernel.org cxl/next for the merge window
> that just opened.
> 
> Now we have some kernel code to test this against (and it looks good)
> I'd like to propose this series for upstream following 3 other series
> already proposed for inclusion:
> 
> Original cover letter with minor updates.
> 
> This patches provides 2 features to the CXL Type-3 Device:
>     1) Volatile Memory Region Support
>     2) Multi-Region support (1 Volatile, 1 Persistent)
> 
> Summary of Changes per-commit:
> 1) Whitespace updates to docs and tests
> 2) Refactor CDAT DSMAS Initialization for multi-region initialization
>    Multi-Region and Volatile Memory support for CXL Type-3 Devices
>    Test and Documentation updates
> 
> The final patch in this series makes 6 major changes to the type-3
> device in order to implement multi-region and volatile region support
>     1) The HostMemoryBackend [hostmem] has been replaced by two
>        [hostvmem] and [hostpmem] to store volatile and persistent memory
>        respectively
>     2) The single AddressSpace has been replaced by two AddressSpaces
>        [hostvmem_as] and [hostpmem_as] to map respective memdevs.
>     3) Each memory region size and total region are stored separately
>     4) The CDAT and DVSEC memory map entries have been updated:
>        a) if vmem is present, vmem is mapped at DPA(0)
>        b) if pmem is present
>           i)  and vmem is present, pmem is mapped at DPA(vmem->size)
>           ii) else, pmem is mapped at DPA(0)
>        c) partitioning of pmem is not supported in this patch set but
>           has been discussed and this design should suffice.
>     5) Read/Write functions have been updated to access AddressSpaces
>        according to the mapping described in #4.  Access to the
>        persistent address space is calculated by (dpa-vmem_len)
>     6) cxl-mailbox has been updated to report the respective size of
>        volatile and persistent memory region
> 
> 
> Gregory Price (2):
>   tests/qtest/cxl-test: whitespace, line ending cleanup
>   hw/cxl: Multi-Region CXL Type-3 Devices (Volatile and Persistent)
> 
>  docs/system/devices/cxl.rst    |  49 ++++--
>  hw/cxl/cxl-mailbox-utils.c     |  26 +--
>  hw/mem/cxl_type3.c             | 294 +++++++++++++++++++++++++--------
>  include/hw/cxl/cxl_device.h    |  11 +-
>  tests/qtest/bios-tables-test.c |   8 +-
>  tests/qtest/cxl-test.c         | 146 +++++++++++-----
>  6 files changed, 392 insertions(+), 142 deletions(-)
>