On Wed, Mar 28, 2018 at 03:11:01PM +0800, Richard Zhu wrote: > - There are three PHY lanes on iMX8QM, and can be > used in the following three cases > 1. a two lanes PCIE_A, and a single lane SATA. > 2. a single lane PCIE_A, a single lane PCIE_B > and a single lane SATA. > 3. a two lanes PCIE_A, and a single lane PCIE_B. > The configuration of the iMX8QM AHCI SATA is relied > on the usage of PCIE ports in the case 1 and 2. > Use standalone iMX8 AHCI SATA probe and enable > functions to enable iMX8QM AHCI SATA support. > - To save power consumption, PHY CLKs can be gated > off after the configurations are done. > - The impedance ratio should be configured refer to > differnet REXT values. > 0x6c <--> REXT value is 85Ohms > 0x80 (default value) <--> REXT value is 100Ohms. > In general, REXT value should be 85ohms in standalone > PCIE HW board design, and 100ohms in SATA standalone > HW board design. > When the PCIE and the SATA are enabled simultaneously > in the HW board design. The REXT value would be set > to 85ohms. > Configure the SATA PHY impedance ratio to 0x6c in > default. > > Signed-off-by: Richard Zhu <hongxing.zhu@xxxxxxx> Applied to libata/for-4.17. Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
