DIPM is unsupported or broken on sunxi. Trying to enable the power management policy med_power_with_dipm on an Allwinner A20 SoC based board leads to immediate I/O errors and the attached SATA disk disappears from the /dev filesystem. A reset (power cycle) is required to make the SATA controller or disk work again. The A10 and A20 SoC data sheets and manuals don't mention DIPM at all [1], so it's fair to assume that it's simply not supported. But even if it was, it should be considered broken and best be disabled in the ahci_sunxi driver. [1] https://github.com/allwinner-zh/documents/tree/master/ Fixes: c5754b5220f0 ("ARM: sunxi: Add support for Allwinner SUNXi SoCs sata to ahci_platform") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Timo Sigurdsson <public_timo.s@xxxxxxxxxxxxxx> Tested-by: Timo Sigurdsson <public_timo.s@xxxxxxxxxxxxxx> --- Changes since v1: - Formal changes to the commit message as suggested by Greg Kroah-Hartman and Sergei Shtylyov (Fixes and Cc lines). No changes to the patch itself. --- drivers/ata/ahci_sunxi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/ata/ahci_sunxi.c b/drivers/ata/ahci_sunxi.c index cb69b737cb49..56b695136977 100644 --- a/drivers/ata/ahci_sunxi.c +++ b/drivers/ata/ahci_sunxi.c @@ -200,7 +200,7 @@ static void ahci_sunxi_start_engine(struct ata_port *ap) } static const struct ata_port_info ahci_sunxi_port_info = { - .flags = AHCI_FLAG_COMMON | ATA_FLAG_NCQ, + .flags = AHCI_FLAG_COMMON | ATA_FLAG_NCQ | ATA_FLAG_NO_DIPM, .pio_mask = ATA_PIO4, .udma_mask = ATA_UDMA6, .port_ops = &ahci_platform_ops, -- 2.26.2