On 1/24/2025 4:48 PM, Dmitry Baryshkov wrote:
On Fri, Jan 24, 2025 at 04:23:03PM +0530, Viken Dadhaniya wrote:
Data transfer mode is fixed by TrustZone (TZ), which currently restricts
developers from modifying the transfer mode from the APPS side.
Document the 'qcom,xfer-mode' properties to select the data transfer mode,
either GPI DMA (Generic Packet Interface) or non-GPI mode (PIO/CPU DMA).
I2C controller can operate in one of two modes based on the
'qcom,xfer-mode' property, and the firmware is loaded accordingly.
Is it possible to load the firmware after it being loaded by TZ? Is it
possible to change the mode at runtime too?
No, firmware can be loaded either from the TZ side or APPS side.
In non-GPI mode, the transfer mode will change runtime between PIO and
CPU DMA based on the data length.
We need to update the device tree property(qcom,xfer-mode) to change the
mode between non-GPI and GPI.
Co-developed-by: Mukesh Kumar Savaliya <quic_msavaliy@xxxxxxxxxxx>
Signed-off-by: Mukesh Kumar Savaliya <quic_msavaliy@xxxxxxxxxxx>
Signed-off-by: Viken Dadhaniya <quic_vdadhani@xxxxxxxxxxx>
---
v1 -> v2:
- Drop 'qcom,load-firmware' property and add 'firmware-name' property in
qup common driver.
- Update commit log.
v1 Link: https://lore.kernel.org/linux-kernel/20241204150326.1470749-2-quic_vdadhani@xxxxxxxxxxx/
---
---
.../devicetree/bindings/i2c/qcom,i2c-geni-qcom.yaml | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/Documentation/devicetree/bindings/i2c/qcom,i2c-geni-qcom.yaml b/Documentation/devicetree/bindings/i2c/qcom,i2c-geni-qcom.yaml
index 9f66a3bb1f80..68e4bf0c84d1 100644
--- a/Documentation/devicetree/bindings/i2c/qcom,i2c-geni-qcom.yaml
+++ b/Documentation/devicetree/bindings/i2c/qcom,i2c-geni-qcom.yaml
@@ -66,6 +66,12 @@ properties:
required-opps:
maxItems: 1
+ qcom,xfer-mode:
+ description: Set the value to 1 for non-GPI (FIFO/CPU DMA) mode and 3 for GPI DMA mode.
+ The default mode is FIFO.
+ $ref: /schemas/types.yaml#/definitions/uint32
+ enum: [1, 3]
+
required:
- compatible
- interrupts
@@ -142,5 +148,6 @@ examples:
interconnect-names = "qup-core", "qup-config", "qup-memory";
power-domains = <&rpmhpd SC7180_CX>;
required-opps = <&rpmhpd_opp_low_svs>;
+ qcom,xfer-mode = <1>;
What does <1> mean? Please provide corresponding defines.
Do we need to add a string instead of a number, like
include/dt-bindings/dma/qcom-gpi.h?
};
...
--
2.34.1
