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arm64: dts: ti: k3-j7200: Fix the L2 cache sets

PATCH Applied Nishanth Menon 3 participants 3 messages Nov 13, 2021 – Dec 6, 2021

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Nishanth Menon

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#0 lore raw

PATCH 1/1 arm64: dts: ti: k3-j7200: Fix the L2 cache sets

A72's L2 cache[1] on J7200[2] is 1MB. A53's L2 is fixed line length of 64 bytes and 16-way set-associative cache structure.

1MB of L2 / 64 (line length) = 16384 ways
16384 ways / 16 = 1024 sets

Fix the l2 cache-sets.

[1] https://developer.arm.com/documentation/100095/0003/Level-2-Memory-System/About-the-L2-memory-system
[2] https://www.ti.com/lit/pdf/spruiu1

Fixes d361ed88455f ("arm64: dts: ti: Add support for J7200 SoC")
Reported-by Peng Fan <[email protected]>
Signed-off-by Nishanth Menon <[email protected]>
---
 arch/arm64/boot/dts/ti/k3-j7200.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
arch/arm64/boot/dts/ti/k3-j7200.dtsi +1 -1
index 958587d3a33d..64fef4e67d76 100644
@@ -86,7 +86,7 @@ L2_0: l2-cache0 {
 		cache-level = <2>;
 		cache-size = <0x100000>;
 		cache-line-size = <64>;
-		cache-sets = <2048>;
+		cache-sets = <1024>;
 		next-level-cache = <&msmc_l3>;
 	};
Signature · 1 line
2.32.0
Reviewed-by on v1 1/1
#1 lore raw
Quoted 1 line · Nishanth Menon

A72's L2 cache[1] on J7200[2] is 1MB. A53's L2 is fixed line length of

                                        ^^^

Same as previous patch, do you mean A72? J7200 does not have an A53 core and this cache node is for A72 cores anyway.

With this fixed,

Reviewed-by Pratyush Yadav <[email protected]>
Quoted 30 lines

64 bytes and 16-way set-associative cache structure.

1MB of L2 / 64 (line length) = 16384 ways
16384 ways / 16 = 1024 sets

Fix the l2 cache-sets.

[1] https://developer.arm.com/documentation/100095/0003/Level-2-Memory-System/About-the-L2-memory-system
[2] https://www.ti.com/lit/pdf/spruiu1

Fixes d361ed88455f ("arm64: dts: ti: Add support for J7200 SoC")
Reported-by Peng Fan <[email protected]>
Signed-off-by Nishanth Menon <[email protected]>
---
 arch/arm64/boot/dts/ti/k3-j7200.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
arch/arm64/boot/dts/ti/k3-j7200.dtsi +1 -1
index 958587d3a33d..64fef4e67d76 100644
@@ -86,7 +86,7 @@ L2_0: l2-cache0 {
 		cache-level = <2>;
 		cache-size = <0x100000>;
 		cache-line-size = <64>;
-		cache-sets = <2048>;
+		cache-sets = <1024>;
 		next-level-cache = <&msmc_l3>;
 	};
Signature · 3 lines
Regards,
Pratyush Yadav
Texas Instruments Inc.
maintainer Applied
#2 lore raw
In reply to Nishanth Menon

Hi Nishanth Menon,

Quoted 3 lines · Nishanth Menon

A72's L2 cache[1] on J7200[2] is 1MB. A53's L2 is fixed line length of 64 bytes and 16-way set-associative cache structure.

Replaced A53 referenc with A72 locally and applied.

Quoted 6 lines

1MB of L2 / 64 (line length) = 16384 ways
16384 ways / 16 = 1024 sets

Fix the l2 cache-sets.

[...]

I have applied the following to branch ti-k3-dts-next on [1]. Thank you!

[1/1] arm64: dts: ti: k3-j7200: Fix the L2 cache sets

      commit: d0c826106f3fc11ff97285102b576b65576654ae

All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent up the chain during the next merge window (or sooner if it is a relevant bug fix), however if problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying to this mail.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/ti/linux.git
--
Vignesh