8. SATA

8.1. Introduction

There is 1 M.2 interface on the ROC-RK3588S-PC development board.

It can be configured as an M.2 SATA3.0 interface by software for use with SSDs that support the SATA protocol, or as an M.2 PCIe2.0 interface by software to support the use of SSDs with the NVMe protocol.

The default software is configured as M.2 SATA3.0 interface, which supports the use of SSDs with SATA protocol.

_images/usage_sata_interface.jpg

8.2. Software configuration

8.2.1. Method 1:Modify system settings

Settings->Connected devices -> M.2 SSD Type

Select the option SATA or PCIe that needs to take effect

_images/swtich_sata_pcie.jpg

The modification will take effect only after the system is restarted

8.2.2. Method 2: DTS configuration

Generally, according to the schematic diagram, select the correct controller node and PHY node to enable in DTS, and close the multiplexed controller node.

There is the following configuration in kernel-5.10/arch/arm64/boot/dts/rockchip/roc-rk3588s-pc.dtsi:

#define M2_SATA_OR_PCIE 1 /*1 = SATA , 0 = PCIe */

/* default use sata3.0 , pcie2.0 optional*/
&combphy0_ps {
    status = "okay";
};

#if M2_SATA_OR_PCIE
&sata0 {
    pinctrl-names = "default";
    pinctrl-0 = <&sata_reset>;
    status = "okay";
};
#else
&pcie2x1l2 {
    reset-gpios = <&gpio3 RK_PD1 GPIO_ACTIVE_HIGH>;
    vpcie3v3-supply = <&vcc3v3_pcie20>;
    status = "okay";
};
#endif

combphy0_ps:PHY node

sata0:sata0 controller node

pcie2x1l2:pcie2x1l2 controller node

M2_SATA_OR_PCIEThe default value is 1, which means it is configured as SATA3.0. If it needs to be configured as PCIe2.0, it needs to be changed to 0

8.3. Mount

8.3.1. Auto mount

Format the hard drive to a usable format in the Android system interface to mount it automatically at boot.

8.3.2. Command to mount manually

  • Find device nodes

ls /dev/block/sd*                                 
/dev/block/sda
  • Formatted as EXT4 file format

mkfs.ext4 /dev/block/sda
  • mount

mount /dev/block/sda /mnt/media_rw/
  • View the mount path

df -h
/dev/block/sda               916G  24K  916G   1% /mnt/media_rw

or

cat /proc/mounts  | grep sda
/dev/block/sda /mnt/media_rw ext4 rw,seclabel,relatime 0 0

8.4. Read and write speed

The transfer rate of SATA3.0 is theoretically 6.0 Gbps. You can refer to the following commands to test the read and write speed:

  • dd

# The path is modified according to the actual mount path
# Write 1G file
echo 3 > /proc/sys/vm/drop_caches
busybox dd if=/dev/zero of=/mnt/media_rw/41AD-09EA/test1 bs=1M count=1024 conv=sync
# Read 1G file
echo 3 > /proc/sys/vm/drop_caches
busybox dd if=/mnt/media_rw/41AD-09EA/test1 of=/dev/null conv=sync
  • fio

# Using fio will format the hard drive
# Write
fio -filename=/dev/block/sda -direct=1 -iodepth 1 -thread -rw=write -ioengine=psync -bs=1M -size=200G -numjobs=30 -runtime=60 -group_reporting -name=mytes
# Read
fio -filename=/dev/block/sda -direct=1 -iodepth 1 -thread -rw=read -ioengine=psync -bs=1M -size=200G -numjobs=30 -runtime=60 -group_reporting -name=mytes