ARM: dts: everest: Add phase corrections for eMMC

The values were determined experimentally via boot tests, not by
measuring the bus behaviour with a scope. We plan to do scope
measurements to confirm or refine the values and will update the
devicetree if necessary once these have been obtained.

However, with the patch we can write and read data without issue, where
as booting the system without the patch failed at the point of mounting
the rootfs.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20210628013605.1257346-1-andrew@aj.id.au
Fixes: 2fc88f92359d ("mmc: sdhci-of-aspeed: Expose clock phase controls")
Fixes: a5c5168478d7 ("ARM: dts: aspeed: Add Everest BMC machine")
Signed-off-by: Joel Stanley <joel@jms.id.au>

diff --git a/arch/arm/boot/dts/aspeed-bmc-ibm-everest.dts b/arch/arm/boot/dts/aspeed-bmc-ibm-everest.dts
index d26a9e16ff7c303da7eeea904ce33a5f9d755840..53c049daf85325a08aa6e390c669e5933111dfec 100644 (file)
--- a/arch/arm/boot/dts/aspeed-bmc-ibm-everest.dts
+++ b/arch/arm/boot/dts/aspeed-bmc-ibm-everest.dts
@@ -2832,6 +2832,7 @@
 
 &emmc {
        status = "okay";
+       clk-phase-mmc-hs200 = <180>, <180>;
 };
 
 &fsim0 {