UPGRADE YOUR BROWSER

We have detected your current browser version is not the latest one. Xilinx.com uses the latest web technologies to bring you the best online experience possible. Please upgrade to a Xilinx.com supported browser:Chrome, Firefox, Internet Explorer 11, Safari. Thank you!

cancel
Showing results for 
Search instead for 
Did you mean: 
Observer mishuk
Observer
2,565 Views
Registered: ‎09-11-2017

Reserve a DDR memory region

Jump to solution

Hello!

I`m using Petalinux 2017.2 with zedBoard BSP.

I reserved DDR memory region through *.dtsi file as described here: https://www.kernel.org/doc/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt

and got boot fail "rootfs image is not initramfs (write error); looks like an initrd".

The same boot fail I got when booting with "mem=" parameter. 

Without "mem=" boot parameter and without memory reservation through *.dtsi file Linux boots fine.

 

I need help!

Tags (3)
0 Kudos
1 Solution

Accepted Solutions
Moderator
Moderator
3,895 Views
Registered: ‎12-04-2016

Re: Reserve a DDR memory region

Jump to solution

Hi

 

You would need to add device tree node something like this, for example, to reserve 0x2000000 of total memory 0x80000000:-

 

memory {
                reg = <0x0 0x0 0x0 0x80000000>;
        };
        reserved-memory {
                #address-cells = <2>;
                #size-cells = <2>;
                ranges;

                te_linux_shm_reserved: te_linux_shm@7e000000 {
                        reg = <0x0 0x7e000000 0x0 0x2000000>;
                };
        };

5 Replies
Moderator
Moderator
3,896 Views
Registered: ‎12-04-2016

Re: Reserve a DDR memory region

Jump to solution

Hi

 

You would need to add device tree node something like this, for example, to reserve 0x2000000 of total memory 0x80000000:-

 

memory {
                reg = <0x0 0x0 0x0 0x80000000>;
        };
        reserved-memory {
                #address-cells = <2>;
                #size-cells = <2>;
                ranges;

                te_linux_shm_reserved: te_linux_shm@7e000000 {
                        reg = <0x0 0x7e000000 0x0 0x2000000>;
                };
        };

Observer mishuk
Observer
2,538 Views
Registered: ‎09-11-2017

Re: Reserve a DDR memory region

Jump to solution

I have already done it.  Take a look at dtsi file attached

0 Kudos
Xilinx Employee
Xilinx Employee
2,521 Views
Registered: ‎02-20-2014

Re: Reserve a DDR memory region

Jump to solution

Can you try some other address for reserved memory? i.e higher 16MB

 

Thanks,

Radhey

0 Kudos
Observer mishuk
Observer
2,502 Views
Registered: ‎09-11-2017

Re: Reserve a DDR memory region

Jump to solution

I have tried three different addresses (low, medium and high): 0xf00000, 0x10000000, 0x1F000000.  I have 512M RAM on the board, so valid RAM addresses are 0...0x20000000.  Each time boot failure.

0 Kudos
Observer mishuk
Observer
2,442 Views
Registered: ‎09-11-2017

Re: Reserve a DDR memory region

Jump to solution

Your answer works.   Problems with initramfs were far away from memory reservation

0 Kudos