Unable to handle kernel paging request at virtual address ffffffffd034001f

[Bhardwaj]

Hi,

We are working with a custom i.MX8M Plus DDR4 board that includes 32 MB QSPI NOR flash.
Our objective is to boot U-Boot, Linux kernel, device tree, and initramfs (rootfs.img) entirely from QSPI flash, without using SD/eMMC.

We are able to successfully boot up to U-Boot (flash.bin) from QSPI flash in custom but it is hangs in kernel.

Generated images for I.MX8MPLUS LPDDR4 EVK (flash.bin,image.gz ,imx8mp-evk.dtb and rootfs.img)  that's working fine.

U-Boot Environment Setup

After booting into U-Boot from QSPI, we configure the following environment variables to load the kernel, device tree, and initramfs from flash:

sf probe 0
setenv loadaddr 0x40480000 // kernel
setenv fdt_addr 0x43000000 //dtb
setenv initrd_addr 0x43800000 //rootfs (minimal initramfs)
setenv kernel_comp_addr_r 0x50000000
setenv kernel_comp_size 0x04000000

Reading Images from QSPI Flash

sf read ${loadaddr} 0x0024D000 0x00E59A6F
sf read ${fdt_addr} 0x010A6B00 0x00014BBA
sf read ${initrd_addr} 0x010BB800 0x00C04DB0

Boot Command

setenv bootargs setenv bootargs "console=ttymxc1,115200 earlycon root=/dev/ram0 rw rdinit=/sbin/init loglevel=8"

booti ${loadaddr} ${initrd_addr} ${fdt_addr}

After this kernel starting But getting error also attaching the error logs:

Unable to handle kernel paging request at virtual address ffffffffd034001f

but sometimes we are able to get till initramfs.

 Attaching the defconfig and dts in kernel (linux-imx) also attaching the logs that hangs in kernel. 

[Manuel_Salas]

Hello @Bhardwaj 

I hope you are doing very well.

Do you already have a DDR Stress Test report for your exact DDR4 part and layout?

If yes, can you share the key results and the SPL ddr4_timing you generated?

Best regards,

Salas.

[Bhardwaj]

Hi @Manuel_Salas ,

Thank you for Support , i am successfully boot the kernel and initrams.

Now i am facing on Ethernet phy not linking .

Working on a custom i.MX8M Plus DDR4 board and facing an issue with Ethernet PHY link-up.

Hardware details:

• SoC: i.MX8M Plus

• PHY: Marvell 88E1512

• Interface: RGMII-ID

• Board: Custom design

Issue description:
I am unable to bring up the Ethernet PHY link. While probing the PHY clocks using an oscilloscope:

• TX_CLK = 125 MHz

• RX_CLK = 125 MHz

So the PHY clocks appear to be present and stable, but the PHY link does not come up and I am unable to ping the PHY.

Also attached the Kernel log for reference. 

Steps performed:

mount -t proc proc /proc

mount -t sysfs sysfs /sys

mount -t devtmpfs devtmpfs /dev

ifconfig eth1 192.168.5.1 up

[ 54.807828] imx-dwmac 30bf0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-0

[ 54.815831] imx-dwmac 30bf0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-1

[ 54.823833] imx-dwmac 30bf0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-2

[ 54.831900] imx-dwmac 30bf0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-3

[ 54.839831] imx-dwmac 30bf0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-4

[ 54.892291] imx-dwmac 30bf0000.ethernet eth1: PHY [stmmac-1:01] driver [Marvell 88E1510] (irq=POLL)

[ 54.901504] imx-dwmac 30bf0000.ethernet eth1: No Safety Features support found

[ 54.908774] imx-dwmac 30bf0000.ethernet eth1: IEEE 1588-2008 Advanced Timestamp supported

[ 54.917533] imx-dwmac 30bf0000.ethernet eth1: registered PTP clock

[ 54.924316] imx-dwmac 30bf0000.ethernet eth1: configuring for phy/rgmii-id link mode

[ 54.932963] 8021q: adding VLAN 0 to HW filter on device eth1

The above procedure working on i.MX8MPLUS EVK and able to ping the PHY.

Observations / Questions:

• PHY clocks are present (125 MHz TX/RX).

• PHY driver is detected, but link never comes up.

• Is there any known device tree, strap configuration, or RGMII delay requirement specific to Marvell 88E1512 on i.MX8M Plus?

• Any recommended PHY register checks or debug steps to further isolate the issue?

Any guidance or pointers would be greatly appreciated.

Thanks in advance.