On 13/12/2022 18:30, Manivannan Sadhasivam wrote:
On Tue, Dec 13, 2022 at 05:24:45PM +0100, Krzysztof Kozlowski wrote:
On 12/12/2022 13:33, Manivannan Sadhasivam wrote:
Register regions of the LLCC banks are located at separate addresses. Currently, the binding just lists the LLCC0 base address and specifies the size to cover all banks. This is not the correct approach since, there are holes and other registers located in between.
So let's specify the base address of each LLCC bank and get rid of reg-names property as it is not needed anymore. It should be noted that the bank count differs for each SoC, so that also needs to be taken into account in the binding.
Cc: stable@vger.kernel.org # 4.19 Fixes: 7e5700ae64f6 ("dt-bindings: Documentation for qcom, llcc") Reported-by: Parikshit Pareek quic_ppareek@quicinc.com Signed-off-by: Manivannan Sadhasivam manivannan.sadhasivam@linaro.org
.../bindings/arm/msm/qcom,llcc.yaml | 97 ++++++++++++++++--- 1 file changed, 83 insertions(+), 14 deletions(-)
diff --git a/Documentation/devicetree/bindings/arm/msm/qcom,llcc.yaml b/Documentation/devicetree/bindings/arm/msm/qcom,llcc.yaml index d1df49ffcc1b..260bc87629a7 100644 --- a/Documentation/devicetree/bindings/arm/msm/qcom,llcc.yaml +++ b/Documentation/devicetree/bindings/arm/msm/qcom,llcc.yaml @@ -33,14 +33,8 @@ properties: - qcom,sm8550-llcc reg:
- items:
- description: LLCC base register region- description: LLCC broadcast base register region- reg-names:
- items:
- const: llcc_base- const: llcc_broadcast_base
- minItems: 2
- maxItems: 9
interrupts: maxItems: 1 @@ -48,7 +42,76 @@ properties: required:
- compatible
- reg
- reg-names
+allOf:
- if:
properties:compatible:contains:enum:- qcom,sc7180-llcc- qcom,sm6350-llcc- then:
properties:reg:items:- description: LLCC0 base register region- description: LLCC broadcast base register region
- if:
properties:compatible:contains:enum:- qcom,sc7280-llcc- then:
properties:reg:items:- description: LLCC0 base register region- description: LLCC1 base register region- description: LLCC broadcast base register regionThis will break all existing users (all systems, bootloaders/firmwares), so you need to explain that in commit msg - why breaking is allowed, who is or is not going to be affected etc. Otherwise judging purely by bindings this is an ABI break.
Reason "This is not the correct approach since, there are holes and other registers located in between." is not enough, because this suggests previous approach was just not the best and you have something better. Better is not a reason for ABI break.
Maybe I need to reword the commit message a bit. But clearly the binding was wrong for rest of the SoCs other than SDM845 as the total size of the LLCC region includes registers of other peripherals like memory controller.
In that case, will you let the binding to be wrong or fix it?
Sure it needs fixing, but as I said you need to explain why breaking ABI is okay and who/where is going to be affected.
Best regards, Krzysztof