Hi Heinrich, On ven., déc. 21 2018, Heinrich Schuchardt <xypron.glpk@xxxxxx> wrote: > The memory area [0x4000000-0x4200000[ is occupied by the PSCI firmware. Any > attempt to access it from Linux leads to an immediate crash. > > So let's make the same memory reservation as the vendor kernel. > > Signed-off-by: Heinrich Schuchardt <xypron.glpk@xxxxxx> We got a similar patch one month ago and Russell King pointed that it didn't match waht he saw on his MACCHIATObin: http://lists.infradead.org/pipermail/linux-arm-kernel/2018-November/612360.html on mine under U-Boot I got: Marvell>> md 0x4000000 04000000: 00000000 00000007 00000005 00000040 ............@... 04000010: 00000001 00001000 00000007 00000001 ................ 04000020: 00000008 00000000 00000009 00000000 ................ 04000030: 0000000a 00000000 ffffffff ffffffff ................ 04000040: ffffffff ffffffff ffffffff ffffffff ................ 04000050: ffffffff ffffffff ffffffff ffffffff ................ 04000060: ffffffff ffffffff ffffffff ffffffff ................ 04000070: ffffffff ffffffff ffffffff ffffffff ................ 04000080: ffffffff ffffffff ffffffff ffffffff ................ 04000090: ffffffff ffffffff ffffffff ffffffff ................ 040000a0: ffffffff ffffffff ffffffff ffffffff ................ 040000b0: ffffffff ffffffff ffffffff ffffffff ................ 040000c0: ffffffff ffffffff ffffffff ffffffff ................ 040000d0: ffffffff ffffffff ffffffff ffffffff ................ 040000e0: ffffffff ffffffff ffffffff ffffffff ................ 040000f0: ffffffff ffffffff ffffffff ffffffff ................ In my case I have an old ATF, however this kind of setting should be done by the bootloader. I am interested by your claim about causing an immediate crash when accessing this region. How did you trigger it? Gregory > --- > v2 > Move the change from armada-8040-mcbin.dts to armada-ap806.dtsi. > I only have a MACCHIATObin for testing but > https://github.com/MarvellEmbeddedProcessors/linux-marvell > has the reservation in that file. > --- > arch/arm64/boot/dts/marvell/armada-ap806.dtsi | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/arch/arm64/boot/dts/marvell/armada-ap806.dtsi b/arch/arm64/boot/dts/marvell/armada-ap806.dtsi > index 7d94c1fa592a..f8dafef83db0 100644 > --- a/arch/arm64/boot/dts/marvell/armada-ap806.dtsi > +++ b/arch/arm64/boot/dts/marvell/armada-ap806.dtsi > @@ -28,6 +28,17 @@ > method = "smc"; > }; > > + reserved-memory { > + #address-cells = <2>; > + #size-cells = <2>; > + ranges; > + > + psci-area@4000000 { > + reg = <0x0 0x4000000 0x0 0x200000>; > + no-map; > + }; > + }; > + > ap806 { > #address-cells = <2>; > #size-cells = <2>; > -- > 2.19.2 > -- Gregory Clement, Bootlin Embedded Linux and Kernel engineering http://bootlin.com