RZ/G2H: How to access QSPI from Linux?

Hi,

I'm trying to access the QSPI flash from Linux but to no avail.

I enabled the following configurations in the r8a774e1_hihope-rzg2h_defconfig file.
(I thought this is enough. Unfortunately, this is not.)

CONFIG_MTD=y
CONFIG_MTD_PARTITIONS=y
CONFIG_SPI_FLASH_MTD=y

After boot,no mtd nodes are availabe in /dev.

# cat /proc/mtd
dev: size erasesize name

# ls -l /dev/m*
crw-rw---- 1 root video 252, 0 Jan 12 09:15 /dev/media0
crw-r----- 1 root kmem 1, 1 Jan 12 09:15 /dev/mem
crw------- 1 root root 10, 59 Jan 12 09:15 /dev/memory_bandwidth
brw-rw---- 1 root disk 179, 0 Jan 12 09:15 /dev/mmcblk0
brw-rw---- 1 root disk 179, 8 Jan 12 09:15 /dev/mmcblk0boot0
brw-rw---- 1 root disk 179, 16 Jan 12 09:15 /dev/mmcblk0boot1
crw------- 1 root root 244, 0 Jan 12 09:15 /dev/mmcblk0rpmb
brw-rw---- 1 root disk 179, 24 Jan 12 09:15 /dev/mmcblk1
brw-rw---- 1 root disk 179, 25 Jan 12 09:15 /dev/mmcblk1p1
brw-rw---- 1 root disk 179, 26 Jan 12 09:15 /dev/mmcblk1p2

The QSPI flash is accessible from U-Boot.

=> sf probe
SF: Detected w25m512jw with page size 256 Bytes, erase size 4 KiB, total 32 MiB

Any help or reference to a documentation will be greatly appreciated.

Thank you.