[v2,0/4] XOR Math Fixups: translation & position

Message

Alison Schofield May 8, 2024, 6:47 p.m. UTC

From: Alison Schofield <[e-mail]>

Changes in v2:
- Rebase on cxl/next
- Remove 'misconfigured root decoder' warn in cxl_region_attach_position() (Dan)
- Comment the implementation of CXL Spec's XORALLBITS in cxl_xor_restore (Dan)
- Prepend new Patch 1 to rename cxl_trace_hpa()-> cxl_translate() (Dan)
- Simplify the setting of position bit in cxl_xor_restore() (Dan)
- Collapse the helper restore_xor_pos() into cxl_xor_restore() 
- Use host bridge ways, not region ways, in cxl_xor_restore().
- Update 'override' comment in cxl_translate() (Dan)
- Clarify via renames (Dan)
	cxl_addr_trans_fn -> cxl_translate_fn
	cxl_xor_trans()   -> cxl_xor_translate()

Link to v1:
https://lore.kernel.org/[e-mail]/


Begin cover letter:

Rather than repeat the individual patch commit message content,
let me describe the flow of this set:

Patch 1: Rename an existing fn - cxl_trace_hpa()-> cxl_translate()

Patch 2: cxl/acpi: Restore XOR'd position bits during address translation
The problem fixed in this patch, bad HPA translations with XOR math,
came to my attention recently. Patch 1 can stand alone, but since that
discovery also shed light on how to repair an issue with calculating
positions in interleave sets (Patch 2,3) they are presented together.

Patch 3 & Patch 4 are paired. Patch 3 presents the new method for
verifying a target position in the list and Patch 3 removes the
old method. These could be squashed.

FYI - the reason I don't present the code removal first is because
I think it is easier to read the diff if I leave in the old root
decoder call back setup for calc_hb, insert the new call back along
the same path, and then rip out the defunct calc_hb. That's the
way I created the patchset and it may be an easier way for reviewers
to follow along with the root decoder callback setup.


Alison Schofield (4):
  cxl/core: Rename cxl_trace_hpa() to cxl_translate()
  cxl/acpi: Restore XOR'd position bits during address translation
  cxl/region: Verify target positions using the ordered target list
  cxl: Remove defunct code calculating host bridge target positions

 drivers/cxl/acpi.c        | 80 ++++++++++++++++-----------------------
 drivers/cxl/core/core.h   |  4 +-
 drivers/cxl/core/mbox.c   |  2 +-
 drivers/cxl/core/port.c   | 21 ++--------
 drivers/cxl/core/region.c | 12 +++++-
 drivers/cxl/core/trace.h  |  2 +-
 drivers/cxl/cxl.h         | 10 ++---
 7 files changed, 54 insertions(+), 77 deletions(-)


base-commit: d99f13843237cf9dbdc1bd873a901662b4aee16f