The use of the AHCI_HFLAG_NO_PMP flag is something which we inherited from the Allwinner android kernel sources, and I've always wanted to test if this is really necessary. So recently I've bought a sata port multiplexer, and I've given this a test spin on both A10 and A20 devices, and it seems to work fine: [ 2.154456] ata1: SATA link up 3.0 Gbps (SStatus 123 SControl 300) [ 2.161092] ata1.15: Port Multiplier 1.2, 0x197b:0x0325 r0, 5 ports, feat 0x5/0xf [ 2.175511] ata1.00: hard resetting link [ 2.524929] ata1.00: SATA link up 3.0 Gbps (SStatus 123 SControl 320) [ 2.531430] ata1.01: hard resetting link [ 2.974465] ata1.01: link resume succeeded after 1 retries [ 3.094932] ata1.01: SATA link up 3.0 Gbps (SStatus 123 SControl 300) [ 3.101431] ata1.02: hard resetting link [ 4.174466] ata1.02: failed to resume link (SControl 0) [ 4.180065] ata1.02: SATA link down (SStatus 0 SControl 0) (and the same for links 3 and 4) Once the NO_PMP flag is removed it correctly sees the 2 disks which I've attached, and I can mount and use them just fine. Unfortunately when I then directly attached a disk to the sata port on the sunxi SoC, and booted a kernel without the AHCI_HFLAG_NO_PMP flag, it would not recognize that disk. It turns out that the sata controller in the sunxi SoCs fails to handle soft-resets issued to directly attached disks, and when pmp support is enabled the kernel will always issue a soft-reset. So add a module parameter to enable pmp usage, and default this to off, so that directly attached disks keep working normally. Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> --- drivers/ata/ahci_sunxi.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/drivers/ata/ahci_sunxi.c b/drivers/ata/ahci_sunxi.c index e44d675..b5aedca 100644 --- a/drivers/ata/ahci_sunxi.c +++ b/drivers/ata/ahci_sunxi.c @@ -27,6 +27,12 @@ #include <linux/regulator/consumer.h> #include "ahci.h" +/* Insmod parameters */ +static bool enable_pmp; +module_param(enable_pmp, bool, 0); +MODULE_PARM_DESC(enable_pmp, + "Enable support for sata port multipliers, only use if you use a pmp!"); + #define AHCI_BISTAFR 0x00a0 #define AHCI_BISTCR 0x00a4 #define AHCI_BISTFCTR 0x00a8 @@ -184,7 +190,15 @@ static int ahci_sunxi_probe(struct platform_device *pdev) goto disable_resources; hpriv->flags = AHCI_HFLAG_32BIT_ONLY | AHCI_HFLAG_NO_MSI | - AHCI_HFLAG_NO_PMP | AHCI_HFLAG_YES_NCQ; + AHCI_HFLAG_YES_NCQ; + + /* + * The sunxi sata controller seems to be unable to successfully do a + * soft reset if no pmp is attached, so disable pmp use unless + * requested, otherwise directly attached disks do not work. + */ + if (!enable_pmp) + hpriv->flags |= AHCI_HFLAG_NO_PMP; rc = ahci_platform_init_host(pdev, hpriv, &ahci_sunxi_port_info); if (rc) -- 2.1.0 -- 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
