linux-pci.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH V2 0/3] PCI: Add basic Compute eXpress Link DVSEC decode
@ 2020-05-18 16:35 Sean V Kelley
  2020-05-18 16:35 ` [PATCH V2 1/3] pci: Add Designated Vendor Specific Capability Sean V Kelley
                   ` (3 more replies)
  0 siblings, 4 replies; 10+ messages in thread
From: Sean V Kelley @ 2020-05-18 16:35 UTC (permalink / raw)
  To: bhelgaas; +Cc: linux-pci, linux-kernel, Sean V Kelley

Changes since v1 [1]:

- Make use pci_info() and FLAG(), as in pcie_init().
- Wrap new cxl_cap in pci_dev struct within #ifdef PCI_CXL.
(Bjorn Helgaas)

- Added functionality for some CXL.mem and CXL.cache helper functions.
Snoop filter helper functions along with a performance hint as
well as a toggle for viral self-isolation mode could be implemented.
However, in the absence of CXL devices with their associated drivers, it
perhaps makes best sense to be in a holding pattern on this until we have
something to exercise it with.

Thoughts?

[1] https://lore.kernel.org/linux-pci/20200515175528.980103-1-sean.v.kelley@linux.intel.com/

This patch series implements basic Designated Vendor-Specific Extended
Capabilities (DVSEC) decode for Compute eXpress Link devices, a new CPU
interconnect building upon PCIe. As a basis for the CXL support it provides
PCI init handling for detection, decode, and caching of CXL device
capabilities.  Moreover, it makes use of the DVSEC Vendor ID and DVSEC ID so
as to identify a CXL capable device. (PCIe r5.0, sec 7.9.6.2)

DocLink: https://www.computeexpresslink.org/

For your reference, a parallel series of patches have been submitted to enable
lspci decode of CXL DVSEC and may be tracked.

Link: https://lore.kernel.org/linux-pci/20200511174618.10589-1-sean.v.kelley@linux.intel.com/

This patch makes use of pending DVSEC related header additions and the
first patch of that series is included here. It can be sorted out when the
upstream merge is done.

Link: https://lore.kernel.org/linux-pci/20200508021844.6911-2-david.e.box@linux.intel.com/

Sample dmesg output of a CXL Type 3 device (CXL.io, CXL.mem):
[    2.997177] pci 0000:6b:00.0: CXL: Cache- IO+ Mem+ Viral- HDMCount 1
[    2.997188] pci 0000:6b:00.0: CXL: cap ctrl status ctrl2 status2 lock
[    2.997201] pci 0000:6b:00.0: CXL: 001e 0002 0000 0000 0000 0000

David E. Box (1):
  pci: Add Designated Vendor Specific Capability

Sean V Kelley (2):
  PCI: Add basic Compute eXpress Link DVSEC decode
  PCI: Add helpers to enable/disable CXL.mem and CXL.cache

 drivers/pci/Kconfig           |   9 ++
 drivers/pci/Makefile          |   1 +
 drivers/pci/cxl.c             | 175 ++++++++++++++++++++++++++++++++++
 drivers/pci/pci.h             |  15 +++
 drivers/pci/probe.c           |   1 +
 include/linux/pci.h           |   3 +
 include/uapi/linux/pci_regs.h |   5 +
 7 files changed, 209 insertions(+)
 create mode 100644 drivers/pci/cxl.c

--
2.26.2


^ permalink raw reply	[flat|nested] 10+ messages in thread

end of thread, other threads:[~2020-05-20 17:43 UTC | newest]

Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-05-18 16:35 [PATCH V2 0/3] PCI: Add basic Compute eXpress Link DVSEC decode Sean V Kelley
2020-05-18 16:35 ` [PATCH V2 1/3] pci: Add Designated Vendor Specific Capability Sean V Kelley
2020-05-18 16:35 ` [PATCH V2 2/3] PCI: Add basic Compute eXpress Link DVSEC decode Sean V Kelley
2020-05-18 16:35 ` [PATCH V2 3/3] PCI: Add helpers to enable/disable CXL.mem and CXL.cache Sean V Kelley
2020-05-18 16:55   ` Bjorn Helgaas
2020-05-19 19:53     ` Sean V Kelley
2020-05-18 18:10   ` kbuild test robot
2020-05-18 20:09   ` kbuild test robot
2020-05-20 17:43   ` Christoph Hellwig
2020-05-18 16:44 ` [PATCH V2 0/3] PCI: Add basic Compute eXpress Link DVSEC decode Bjorn Helgaas

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).