Hello. This is probably exactly the case I encountered at the time. [1] For myself, I solved this problem through the device tree. [2] Let's see which solution to the problem will be better.
[1] https://lore.pengutronix.de/barebox/cap1tnvs_bwd_gxcdwmh61dy9vtg1gsy7gsy8wr9vae+ksqa...@mail.gmail.com/T/ [2] https://github.com/MacroGroup/barebox/blob/macro/arch/arm/dts/rk3588-diasom-btb.dtsi#L234 Thanks! пт, 11 апр. 2025 г. в 19:22, Sascha Hauer <s.ha...@pengutronix.de>: > > On Fri, Apr 11, 2025 at 05:20:20PM +0200, Michael Tretter wrote: > > RK3588 has two known memory gaps when using 16+ GiB DRAM, > > [0x3fc000000, 0x3fc500000) and [0x3fff00000, 0x400000000). > > > > Skip both gaps when initializing the DRAM on rk3588 to avoid running > > into an exception when running memtest on an rk3588 board with 16+ GiB > > DRAM. > > > > The information about the gaps is taken from a patch by Jonas Karlman to > > the U-Boot mailing list [0]. > > > > [0] https://lore.kernel.org/all/20250405153832.1427549-5-jo...@kwiboo.se/ > > > > Signed-off-by: Michael Tretter <m.tret...@pengutronix.de> > > --- > > The start and end addresses of the gaps probably should be put into of > > rockchip_dmc_drvdata and only set for the rk3588. Any suggestion how to > > implement this more nicely would be very welcome. > > Looks like the rk3588 currently is the only SoC that can have that much > memory that it hits the gaps. You could add a comment that the gaps are > only verified on rk3588 and need another look once the next SoC is > added. > > Once we are there we can add a function pointer into struct > rockchip_dmc_drvdata > doing the right thing, but I think for now it's fine the way you did it. > > Sascha > > > --- > > arch/arm/mach-rockchip/dmc.c | 20 ++++++++++++++++++-- > > 1 file changed, 18 insertions(+), 2 deletions(-) > > > > diff --git a/arch/arm/mach-rockchip/dmc.c b/arch/arm/mach-rockchip/dmc.c > > index 86e61f311661..cf63fdb5a8bb 100644 > > --- a/arch/arm/mach-rockchip/dmc.c > > +++ b/arch/arm/mach-rockchip/dmc.c > > @@ -27,6 +27,12 @@ > > #define RK3568_INT_REG_START RK3399_INT_REG_START > > #define RK3588_INT_REG_START RK3399_INT_REG_START > > > > +/* RK3588 has two known memory gaps when using 16+ GiB DRAM */ > > +#define DRAM_GAP1_START 0x3fc000000 > > +#define DRAM_GAP1_END 0x3fc500000 > > +#define DRAM_GAP2_START 0x3fff00000 > > +#define DRAM_GAP2_END 0x400000000 > > + > > struct rockchip_dmc_drvdata { > > unsigned int os_reg2; > > unsigned int os_reg3; > > @@ -220,9 +226,19 @@ static int rockchip_dmc_probe(struct device *dev) > > arm_add_mem_device("ram0", membase, > > min_t(resource_size_t, drvdata->internal_registers_start, > > memsize) - membase); > > > > - /* ram1, remaining RAM beyond 32bit space */ > > + /* ram1, RAM beyond 32bit space up to first gap */ > > if (memsize > SZ_4G) > > - arm_add_mem_device("ram1", SZ_4G, memsize - SZ_4G); > > + arm_add_mem_device("ram1", SZ_4G, > > + min_t(resource_size_t, DRAM_GAP1_START, memsize) - > > SZ_4G); > > + > > + /* ram2, RAM between first and second gap */ > > + if (memsize > DRAM_GAP1_END) > > + arm_add_mem_device("ram2", DRAM_GAP1_END, > > + min_t(resource_size_t, DRAM_GAP2_START, memsize) - > > DRAM_GAP1_END); > > + > > + /* ram3, remaining RAM after second gap */ > > + if (memsize > DRAM_GAP2_END) > > + arm_add_mem_device("ram3", DRAM_GAP2_END, memsize - > > DRAM_GAP2_END); > > > > return 0; > > } > > -- > > 2.39.5 > > > > > > > > -- > Pengutronix e.K. | | > Steuerwalder Str. 21 | http://www.pengutronix.de/ | > 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | > Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | >
