On 24/01/2025 16:16, Viken Dadhaniya wrote: > > > On 1/24/2025 8:33 PM, Dmitry Baryshkov wrote: >> On Fri, Jan 24, 2025 at 05:52:24PM +0530, Viken Dadhaniya wrote: >>> >>> >>> 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. >> >> You answer actually reads as "No, yes" (excuse me, non-native here). >> Most likely you mean that it can not be reloaded once either TZ or APPS >> has loaded it. > > Yes correct. it can not be reloaded once either TZ or APPS has loaded it. > >> >>> 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. >> >> So, is it actually possible to change the mode? E.g. if the TZ has >> loaded the firmware and configured SE for PIO/SE DMA, is it possible to >> change it to GPI DMA? > > No, if the TZ has loaded the firmware, it is not possible to switch from > non-GPI (PIO/SE DMA) to GPI DMA mode. > >> >>> >>>> >>>>> >>>>> 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? >> >> You need to '#define FOO_BAR 1', then another one for 3. String is a >> "string", it's not required here (in my opinion). >> > > Sure, I will update it in the next patch. Well, no. Not 3 but 2, because why having gap there? But anyway use string and explain what is GPI. I assume that DMA is present in both cases, you just choose not to use it? If so, then why? Best regards, Krzysztof
