Hello,

Applied the following to libata/for-4.5-fixes.

Thanks.

------ 8< ------
>From 566d1827df2ef0cbe921d3d6946ac3007b1a6938 Mon Sep 17 00:00:00 2001
From: Tejun Heo <[email protected]>
Date: Fri, 15 Jan 2016 15:13:05 -0500
Subject: [PATCH] libata: disable forced PORTS_IMPL for >= AHCI 1.3

Some early controllers incorrectly reported zero ports in PORTS_IMPL
register and the ahci driver fabricates PORTS_IMPL from the number of
ports in those cases.  This hasn't mattered but with the new nvme
controllers there are cases where zero PORTS_IMPL is valid and should
be honored.

Disable the workaround for >= AHCI 1.3.

Signed-off-by: Tejun Heo <[email protected]>
Reported-by: Andy Lutomirski <[email protected]>
Link: 
http://lkml.kernel.org/g/calcetru7ymvxedhjaushohehdwifjgapdw--bkxsp0jmjkg...@mail.gmail.com
Cc: Sergei Shtylyov <[email protected]>
Cc: [email protected]
---
 drivers/ata/libahci.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c
index 284a176..4029679 100644
--- a/drivers/ata/libahci.c
+++ b/drivers/ata/libahci.c
@@ -496,8 +496,8 @@ void ahci_save_initial_config(struct device *dev, struct 
ahci_host_priv *hpriv)
                }
        }
 
-       /* fabricate port_map from cap.nr_ports */
-       if (!port_map) {
+       /* fabricate port_map from cap.nr_ports for < AHCI 1.3 */
+       if (!port_map && vers < 0x10300) {
                port_map = (1 << ahci_nr_ports(cap)) - 1;
                dev_warn(dev, "forcing PORTS_IMPL to 0x%x\n", port_map);
 
-- 
2.5.0

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