[PATCH 4.9 165/245] ata: ahci_sunxi: Disable DIPM

From: Greg Kroah-Hartman
Date: Mon Jul 19 2021 - 11:17:37 EST

From: Timo Sigurdsson <public_timo.s@xxxxxxxxxxxxxx>

commit f6bca4d91b2ea052e917cca3f9d866b5cc1d500a upstream.

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>
Link: https://lore.kernel.org/r/20210614072539.3307-1-public_timo.s@xxxxxxxxxxxxxx
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

drivers/ata/ahci_sunxi.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/ata/ahci_sunxi.c
+++ b/drivers/ata/ahci_sunxi.c
@@ -165,7 +165,7 @@ static void ahci_sunxi_start_engine(stru

static const struct ata_port_info ahci_sunxi_port_info = {
.pio_mask = ATA_PIO4,
.udma_mask = ATA_UDMA6,
.port_ops = &ahci_platform_ops,