[PATCH] arm64: dts: rockchip: Enable HS400 enhanced strobe on Kobol Helios64 eMMC

[Igor Velkov via B4 Relay]

From: Igor Velkov <iav at iav.lv>

The eMMC of Helios64 runs in HS200. Run it in HS400 enhanced strobe at
150 MHz, as on Gru. The strobe line goes straight from the SoC to the
DS pin of the eMMC with no pull-down on the board, so enable the one
in the eMMC PHY.

Assisted-by: LLM
Signed-off-by: Igor Velkov <iav at iav.lv>
---
Schematic, sheet 14:
https://wiki.kobol.io/helios64/files/schematics/Helios64_Schematics_Rev1.2.pdf

Tested on mainline with three 2 GiB write and read-back passes, no
errors. Raw reads go from 180 MB/s in HS200 to 247 MB/s. Without the
pull-down, writes dropped to about 1 MB/s with repeated
"mmc1: running CQE recovery".
---
 arch/arm64/boot/dts/rockchip/rk3399-kobol-helios64.dts | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/arm64/boot/dts/rockchip/rk3399-kobol-helios64.dts b/arch/arm64/boot/dts/rockchip/rk3399-kobol-helios64.dts
index 63ad79b4c8ac..f78482c4c285 100644
--- a/arch/arm64/boot/dts/rockchip/rk3399-kobol-helios64.dts
+++ b/arch/arm64/boot/dts/rockchip/rk3399-kobol-helios64.dts
@@ -320,6 +320,7 @@ &cpu_l3 {
 };
 
 &emmc_phy {
+	rockchip,enable-strobe-pulldown;
 	status = "okay";
 };
 
@@ -586,8 +587,11 @@ &saradc {
 };
 
 &sdhci {
+	assigned-clock-rates = <150000000>;
 	bus-width = <8>;
 	mmc-hs200-1_8v;
+	mmc-hs400-1_8v;
+	mmc-hs400-enhanced-strobe;
 	non-removable;
 	vqmmc-supply = <&vcc1v8_sys_s0>;
 	status = "okay";

---
base-commit: d2abcbb905b0e4b2e06b257fa1e5bcf4faa6dbda
change-id: 20261011-b4-helios64-emmc-hs400-9c784f35d8dd

Best regards,
-- 
Igor Velkov <iav at iav.lv>