Hi Marek cc: Michael
On Tue, Mar 5, 2019 at 4:37 AM Marek Vasut marek.vasut@gmail.com wrote:
The ATF can pass additional information via the first four registers, x0...x3. The R-Car Gen3 with mainline ATF, register x1 contains pointer to a device tree with platform information. Parse this device tree and extract DRAM size information from it. This is useful on systems where the DRAM size can vary between configurations.
1. Do the ATF changes supporting this feature already exist in mainline ATF?
2. I see more DRAM-related compile-time knobs in vanilla ATF: ➜ arm-trusted-firmware (c48d02bade88) $ grep "DRAM.*:" plat/renesas/rcar/platform.mk RCAR_DRAM_SPLIT := 0 RCAR_DRAM_LPDDR4_MEMCONF :=1 RCAR_DRAM_DDR3L_MEMCONF :=1 RCAR_DRAM_DDR3L_MEMDUAL :=1 RCAR_DRAM_CHANNEL :=15
My understanding is that these are local to ATF and U-Boot can stay agnostic about them? IOW, DRAM start and size are totally enough for U-Boot? TIA!
Best regards, Eugeniu.