Future uapi needs to give userspace the ability to select the pat_index
for a given vm_bind. However we need to be able to extract the coherency
mode from the provided pat_index to ensure it's compatible with the
cpu_caching mode set at object creation. There are various security
reasons for why this matters. However the pat_index itself is very
platform specific, so seems reasonable to annotate each platform
definition of the pat table. On some older platforms there is no
explicit coherency mode, so we just pick whatever makes sense.
v2:
- Simplify with COH_AT_LEAST_1_WAY
- Add some kernel-doc
v3 (Matt Roper):
- Some small tweaks
v4:
- Rebase
v5:
- Rebase on Xe2 PAT additions
v6:
- Rebase on removal of coh_mode from uapi
Bspec: 45101, 44235 #xe
Bspec: 70552, 71582, 59400 #xe2
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Pallavi Mishra <pallavi.mishra@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: José Roberto de Souza <jose.souza@intel.com>
Cc: Filip Hazubski <filip.hazubski@intel.com>
Cc: Carl Zhang <carl.zhang@intel.com>
Cc: Effie Yu <effie.yu@intel.com>
Cc: Zhengguo Xu <zhengguo.xu@intel.com>
Cc: Francois Dugast <francois.dugast@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Reviewed-by: Pallavi Mishra <pallavi.mishra@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
This is useful to debug cache issues, to double check if the PAT
indexes match what they were supposed to be set to from spec.
v2: Add separate functions for XeHP, XeHPC and XeLPG so it correctly
reads the index based on MCR/REG registers and also decodes the
fields (Matt Roper)
v3: Starting with XeHPC, do not translate values to human-readable
formats as the main goal is to make it easy to compare the table
with the spec. Also, share a single array for xelp/xehp str map
(Matt Roper)
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://lore.kernel.org/r/20231006182325.3617685-3-lucas.demarchi@intel.com
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
These should replace the _MMIO() and MCR_REG() from i915, with the goal
of being more extensible, allowing to pass the additional fields for
struct xe_reg and struct xe_reg_mcr. Replace all uses of _MMIO() and
MCR_REG() in xe.
Since the RTP, reg-save-restore and WA infra are not ready to use the
new type, just undef the macro like was done for the i915 types
previously. That conversion will come later.
v2: Remove MEDIA_SOFT_SCRATCH_COUNT/MEDIA_SOFT_SCRATCH re-added by
mistake (Matt Roper)
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://lore.kernel.org/r/20230427223256.1432787-8-lucas.demarchi@intel.com
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Clarify a few things related to the PAT programming, particularly on
MTL:
- The register type doesn't change depending on the GT - what
happens is that media GT writes to other set of registers that
are not MCR
- Remove "UNICAST": otherwise it's confusing why it's not using
MCR registers with the unicast function variant
Also, there isn't much reason to keep those parts as macros: promote
them to proper functions and let the compiler inline if it sees fit.
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://lore.kernel.org/r/20230427223256.1432787-5-lucas.demarchi@intel.com
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Starting with MTL, the number of entries in the PAT table increased to
16. The register offset jumped between index 7 and index 8, so a slight
adjustment is needed to ensure the PAT_INDEX macros select the proper
offset for the upper half of the table.
Note that although there are 16 registers in the hardware, the driver is
currently only asked to program the first 5, and we leave the rest at
their hardware default values. That means we don't actually touch the
upper half of the PAT table in the driver today and this patch won't
have any functional effect [yet].
Bspec: 44235
Reviewed-by: Nirmoy Das <nirmoy.das@intel.com>
Link: https://lore.kernel.org/r/20230324210415.2434992-7-matthew.d.roper@intel.com
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
The PAT_INDEX registers are MCR registers on some platforms and unicast
on others. On MTL the handling even varies between GTs: the primary GT
uses MCR registers while the media GT uses unicast registers. Let's add
proper MCR programming on the relevant platforms/GTs.
Given that we PAT tables to change pretty regularly on future platforms,
we'll make PAT programming an exception to the usual model of assuming
new platforms should inherit the previous platform's behavior. Instead
we'll raise a warning if the current platform isn't handled in the
if/else ladder. This should help prevent subtle cache misbehavior if we
forget to add the table for a new platform.
Bspec: 66534, 67609, 67788
Reviewed-by: Nirmoy Das <nirmoy.das@intel.com>
Link: https://lore.kernel.org/r/20230324210415.2434992-4-matthew.d.roper@intel.com
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
