[RFC PATCH u-boot 00/12] U-Boot LTO (Sandbox + ARM Nokia RX-51)

[Adam Ford]

On Thu, Mar 4, 2021 at 9:59 AM Marek Behun <marek.behun at nic.cz> wrote:
>
> On Thu, 4 Mar 2021 09:07:33 -0600
> Adam Ford <aford173 at gmail.com> wrote:
>
> > Interesting.  with LTO enabled, the DRAM reports 7.2 GB and hangs.
> > Without LTO, U-Boot boots fine.
> >
> > LTO:
> > OMAP3630/3730-GP ES1.2, CPU-OPP2, L3-200MHz, Max CPU Clock 1 GHz
> > Model: LogicPD Zoom DM3730 Torpedo + Wireless Development Kit
> > Logic DM37x/OMAP35x reference board + LPDDR/NAND
> > DRAM:  7.2 GiB
> > <hang>
> >
> > Without LTO:
> > OMAP3630/3730-GP ES1.2, CPU-OPP2, L3-200MHz, Max CPU Clock 1 GHz
> > Model: LogicPD Zoom DM3730 Torpedo + Wireless Development Kit
> > Logic DM37x/OMAP35x reference board + LPDDR/NAND
> > DRAM:  256 MiB
> > NAND:  512 MiB
> > MMC:   OMAP SD/MMC: 0
> > Loading Environment from NAND... OK
> > OMAP die ID: 619e00029ff800000168300f1502501f
> > Net:   smc911x-0
> > Hit any key to stop autoboot:  0
> > OMAP Logic #
>
> In which file is the code for determining dram for this board?
> Try adding
> CFLAGS_REMOVE_file.o := $(LTO_CFLAGS)
> to Makefile in the directory where the file is located.
>

Marek / Tom,

I modified arch/arm/mach-omap2/omap3/Makefile with the above patch,
and the U-Boot portion appears correctly now when I use an SPL that
was compiled without LTO:

U-Boot 2021.04-rc3-00277-ge47d3424df-dirty (Mar 04 2021 - 16:09:09 -0600)

OMAP3630/3730-GP ES1.2, CPU-OPP2, L3-200MHz, Max CPU Clock 1 GHz
Model: LogicPD Zoom DM3730 Torpedo + Wireless Development Kit
Logic DM37x/OMAP35x reference board + LPDDR/NAND
DRAM:  256 MiB
NAND:  512 MiB
MMC:   OMAP SD/MMC: 0
Loading Environment from NAND... OK
OMAP die ID: 619e00029ff800000168300f1502501f
Net:   eth0: ethernet at 08000000
Hit any key to stop autoboot:  0
OMAP Logic #

Unfortunately, the SPL portion doesn't boot when compiled with SPL,
but I think we're getting closer.  Unfortunately, I don't have a good
debugger to use and without any serial port output, it may be
difficult for me to debug.

Tom,

Since you have an OMAP3 board:

diff --git a/arch/arm/mach-omap2/omap3/Makefile
b/arch/arm/mach-omap2/omap3/Makefile
index 91ed8ebc9f..a2cc21c6d2 100644
--- a/arch/arm/mach-omap2/omap3/Makefile
+++ b/arch/arm/mach-omap2/omap3/Makefile
@@ -6,6 +6,8 @@
 # If clock.c is compiled for Thumb2, then it fails on OMAP3530
 CFLAGS_clock.o += -marm

+CFLAGS_REMOVE_file.o := $(LTO_CFLAGS)
+
 obj-y  := lowlevel_init.o

 obj-y  += board.o



> Marek