On 05.09.24 08:32, Krzysztof Kozlowski wrote:

On Wed, Sep 04, 2024 at 12:00:11PM +0200, Jan Kiszka wrote:

quoted

From: Jan Kiszka <jan.kiszka@siemens.com>

The PVU on the AM65 SoC is capable of restricting DMA from PCIe devices
to specific regions of host memory. Add the optional property
"memory-regions" to point to such regions of memory when PVU is used.

Since the PVU deals with system physical addresses, utilizing the PVU
with PCIe devices also requires setting up the VMAP registers to map the
Requester ID of the PCIe device to the CBA Virtual ID, which in turn is
mapped to the system physical address. Hence, describe the VMAP
registers which are optionally unless the PVU shall used for PCIe.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---
CC: Lorenzo Pieralisi <lpieralisi@kernel.org>
CC: "Krzysztof Wilczyński" <redacted>
CC: Bjorn Helgaas <bhelgaas@google.com>
CC: linux-pci@vger.kernel.org
---
 .../bindings/pci/ti,am65-pci-host.yaml        | 52 ++++++++++++++-----
 1 file changed, 40 insertions(+), 12 deletions(-)

diff --git a/Documentation/devicetree/bindings/pci/ti,am65-pci-host.yaml b/Documentation/devicetree/bindings/pci/ti,am65-pci-host.yaml
index 0a9d10532cc8..d8182bad92de 100644
--- a/Documentation/devicetree/bindings/pci/ti,am65-pci-host.yaml
+++ b/Documentation/devicetree/bindings/pci/ti,am65-pci-host.yaml

@@ -19,16 +19,6 @@ properties:
       - ti,am654-pcie-rc
       - ti,keystone-pcie
 
-  reg:
-    maxItems: 4
-
-  reg-names:
-    items:
-      - const: app
-      - const: dbics
-      - const: config
-      - const: atu

Nothing improved here.

Yes, explained the background to you. Sorry, if you do not address my
replies, I'm lost with your feedback.

quoted

-
   interrupts:
     maxItems: 1
 

@@ -84,12 +74,48 @@ if:
       enum:
         - ti,am654-pcie-rc
 then:
+  properties:
+    reg:
+      minItems: 4
+      maxItems: 6
+
+    reg-names:
+      minItems: 4
+      items:
+        - const: app
+        - const: dbics
+        - const: config
+        - const: atu
+        - const: vmap_lp
+        - const: vmap_hp
+
+    memory-region:
+      minItems: 1

Missing maxItems

Same as above. Please address my answers.

quoted

+      description: |
+        phandle to one or more restricted DMA pools to be used for all devices
+        behind this controller. The regions should be defined according to
+        reserved-memory/shared-dma-pool.yaml.
+      items:
+        maxItems: 1

And this feels redundant.

I can drop that if it's not needed. Unfortunately, schemas are far from
being intuitive to me.

Jan

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