Re: [Patch v6 3/4] dt-bindings: memory: Update reg maxitems for tegra186

From: Ashish Mhetre
Date: Mon Apr 11 2022 - 11:41:50 EST




On 4/11/2022 8:59 PM, Dmitry Osipenko wrote:
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On 4/11/22 18:02, Ashish Mhetre wrote:


On 4/10/2022 7:51 PM, Dmitry Osipenko wrote:
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06.04.2022 08:24, Ashish Mhetre пишет:
memory-controller@2c00000 {
compatible = "nvidia,tegra186-mc";
- reg = <0x0 0x02c00000 0x0 0xb0000>;
+ reg = <0x0 0x02c00000 0x0 0x10000>, /* MC-SID */
+ <0x0 0x02c10000 0x0 0x10000>, /* Broadcast
channel */
+ <0x0 0x02c20000 0x0 0x10000>, /* MC0 */
+ <0x0 0x02c30000 0x0 0x10000>, /* MC1 */
+ <0x0 0x02c40000 0x0 0x10000>, /* MC2 */
+ <0x0 0x02c50000 0x0 0x10000>; /* MC3 */
+ reg-names = "mc-sid", "mc-broadcast", "mc0", "mc1",
"mc2", "mc3";

The "mc-" prefix feels redundant to me, I'd name the regs like this:

"sid", "broadcast", "ch0", "ch1", "ch2", "ch3"


You should also add validation of the regs/reg-names to the yaml based
on SoC version. I.e. it's not enough to only bump the maxItems.

Okay, I will add validation of reg-names as following:

reg-names:
minItems: 0
maxItems: 6
items:
- const: sid
- const: broadcast
- const: ch0
- const: ch1
- const: ch2
- const: ch3


We will have to keep minItems to 0 in order to make it compatible with
old DT, right?

Bindings are about the latest DTs. In general older dtbs must be updated
and you must get error from the schema checker for older DTs. It's only
drivers that should care about older dtbs.

On v5 Krzysztof mentioned that old DTS will start failing with new
bindings https://lkml.org/lkml/2022/3/22/907.
So I just wanted to confirm whether it's fine if updated bindings
start to fail with old DTS?