Re: [PATCH 4/5] ARM: Add basic support for EcoNet EN7523 SoC

From: Bert Vermeulen
Date: Mon Aug 09 2021 - 09:04:14 EST


On 8/9/21 2:46 PM, Geert Uytterhoeven wrote:
I didn't make that patch, but it turns out it's needed to get PSCI working;
detection hangs without it. That makes no sense to me, but I'll examine further.

Probably PSCI relies on the memory contents at the start of RAM not
being overwritten?

It turns out to hang at the first SMC call, for PSCI_0_2_FN_PSCI_VERSION. I assume the receiver of that call, ATF, got dropped in that region by the vendor's U-Boot.

Does it help if you remove the first 512 KiB from the /memory node
(which should be declared in en7523-evb.dts instead of en7523.dtsi
BTW)?
No it doesn't, was just trying to work out why not, in your fdt_check_mem_start().

Anyway that was Arnd's first suggestion, but I think his second suggestion (teach fdt_check_mem_start() about /memreserve/) is the cleaner approach to this. Opinions?


--
Bert Vermeulen
bert@xxxxxxxx