[v2,0/2] hw/mem: CXL Type-3 Volatile Memory Support

Message

Jonathan Cameron Feb. 17, 2023, 5:56 p.m. UTC

v2:
- Fix an off by one in address space matching when both volatile and
  persistent memory is in present (meant 1st byte of persistent memory
  not readale)
- Picked up tags (thanks to all who tested!)

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/pending.

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    1) The HostMemoryBackend [hostmem] has been replaced by two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    2) The single AddressSpace has been replaced by two AddressSpaces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             | 300 +++++++++++++++++++++++++--------
 include/hw/cxl/cxl_device.h    |  11 +-
 tests/qtest/bios-tables-test.c |   8 +-
 tests/qtest/cxl-test.c         | 146 +++++++++++-----
 6 files changed, 398 insertions(+), 142 deletions(-)