Fan Ni wrote:
> On Sun, Apr 13, 2025 at 05:52:10PM -0500, Ira Weiny wrote:
> > Devices which optionally support Dynamic Capacity (DC) are configured
> > via mailbox commands. CXL 3.2 section 9.13.3 requires the host to issue
> > the Get DC Configuration command in order to properly configure DCDs.
> > Without the Get DC Configuration command DCD can't be supported.
> >
> > Implement the DC mailbox commands as specified in CXL 3.2 section
> > 8.2.10.9.9 (opcodes 48XXh) to read and store the DCD configuration
> > information. Disable DCD if an invalid configuration is found.
> >
> > Linux has no support for more than one dynamic capacity partition. Read
> > and validate all the partitions but configure only the first partition
> > as 'dynamic ram A'. Additional partitions can be added in the future if
> > such a device ever materializes. Additionally is it anticipated that no
> > skips will be present from the end of the pmem partition. Check for an
> > disallow this configuration as well.
> >
> > Linux has no use for the trailing fields of the Get Dynamic Capacity
> > Configuration Output Payload (Total number of supported extents, number
> > of available extents, total number of supported tags, and number of
> > available tags). Avoid defining those fields to use the more useful
> > dynamic C array.
> >
> > Based on an original patch by Navneet Singh.
> >
> > Signed-off-by: Ira Weiny <ira.we...@intel.com>
> >
> > ---
> > Changes:
> > [iweiny: rebase]
> > [iweiny: Update spec references to 3.2]
> > [djbw: Limit to 1 partition]
> > [djbw: Avoid inter-partition skipping]
> > [djbw: s/region/partition/]
> > [djbw: remove cxl_dc_region[partition]_info->name]
> > [iweiny: adjust to lack of dcd_cmds in mds]
> > [iweiny: remove extra 'region' from names]
> > [iweiny: remove unused CXL_DYNAMIC_CAPACITY_SANITIZE_ON_RELEASE_FLAG]
> > ---
> > drivers/cxl/core/hdm.c | 2 +
> > drivers/cxl/core/mbox.c | 179
> > ++++++++++++++++++++++++++++++++++++++++++++++++
> > drivers/cxl/cxl.h | 1 +
> > drivers/cxl/cxlmem.h | 54 ++++++++++++++-
> > drivers/cxl/pci.c | 3 +
> > 5 files changed, 238 insertions(+), 1 deletion(-)
> ...
> > /* Set Timestamp CXL 3.0 Spec 8.2.9.4.2 */
> > struct cxl_mbox_set_timestamp_in {
> > __le64 timestamp;
> > @@ -845,9 +871,24 @@ enum {
> > int cxl_internal_send_cmd(struct cxl_mailbox *cxl_mbox,
> > struct cxl_mbox_cmd *cmd);
> > int cxl_dev_state_identify(struct cxl_memdev_state *mds);
> > +
> > +struct cxl_mem_dev_info {
> > + u64 total_bytes;
> > + u64 volatile_bytes;
> > + u64 persistent_bytes;
> > +};
>
> Defined, but never used.
Shoot... That was from a previous version of work on type2...
Thanks for the catch!
Ira
[snip]
