Thread (95 messages) 95 messages, 8 authors, 2024-10-17
STALE633d
Revisions (4)
  1. v1 [diff vs current]
  2. v2 current
  3. v3 [diff vs current]
  4. v4 [diff vs current]

[PATCH v2 3/8] ACPICA: IORT: Update for revision E.f

From: Jason Gunthorpe <jgg@nvidia.com>
Date: 2024-08-27 15:58:32
Also in: kvm, linux-acpi, linux-iommu, linux-patches
Subsystem: acpi, acpi component architecture (acpica), the rest · Maintainers: "Rafael J. Wysocki", Saket Dumbre, Linus Torvalds

From: Nicolin Chen <redacted>

ACPICA commit c4f5c083d24df9ddd71d5782c0988408cf0fc1ab

The IORT spec, Issue E.f (April 2024), adds a new CANWBS bit to the Memory
Access Flag field in the Memory Access Properties table, mainly for a PCI
Root Complex.

This CANWBS defines the coherency of memory accesses to be not marked IOWB
cacheable/shareable. Its value further implies the coherency impact from a
pair of mismatched memory attributes (e.g. in a nested translation case):
  0x0: Use of mismatched memory attributes for accesses made by this
       device may lead to a loss of coherency.
  0x1: Coherency of accesses made by this device to locations in
       Conventional memory are ensured as follows, even if the memory
       attributes for the accesses presented by the device or provided by
       the SMMU are different from Inner and Outer Write-back cacheable,
       Shareable.

Link: https://github.com/acpica/acpica/commit/c4f5c083
Signed-off-by: Nicolin Chen <redacted>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
---
 include/acpi/actbl2.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/include/acpi/actbl2.h b/include/acpi/actbl2.h
index e27958ef82642f..9a7acf403ed3c8 100644
--- a/include/acpi/actbl2.h
+++ b/include/acpi/actbl2.h
@@ -453,7 +453,7 @@ struct acpi_table_ccel {
  * IORT - IO Remapping Table
  *
  * Conforms to "IO Remapping Table System Software on ARM Platforms",
- * Document number: ARM DEN 0049E.e, Sep 2022
+ * Document number: ARM DEN 0049E.f, Apr 2024
  *
  ******************************************************************************/
 
@@ -524,6 +524,7 @@ struct acpi_iort_memory_access {
 
 #define ACPI_IORT_MF_COHERENCY          (1)
 #define ACPI_IORT_MF_ATTRIBUTES         (1<<1)
+#define ACPI_IORT_MF_CANWBS             (1<<2)
 
 /*
  * IORT node specific subtables
-- 
2.46.0

Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help