diff mbox series

[09/21] PCI: imx6: Drop imx6_pcie_link_up()

Message ID 20181221072716.29017-10-andrew.smirnov@gmail.com (mailing list archive)
State New, archived
Delegated to: Bjorn Helgaas
Headers show
Series i.MX6, DesignWare PCI improvements | expand

Commit Message

Andrey Smirnov Dec. 21, 2018, 7:27 a.m. UTC
Until commit 4d107d3b5a68 ("PCI: imx6: Move link up check into
imx6_pcie_wait_for_link()") the driver relied on both LINK_UP and
LINK_IN_TRAINING to determine if PCIE link was up.

I can't seem to find out why, but code using LINK_IN_TRAINING seem to
disappear after commit 886bc5ceb5cc ("PCI: designware: Add generic
dw_pcie_wait_for_link()") and from then on only LINK_UP seems to be
tested (dw_pcie_wait_for_link() -> dw_pcie_link_up() ->
imx6_pcie_link_up()).

At the same time the default behavior of dw_pcie_link_up() went from
using just LINK_UP in commit dac29e6c5460 ("PCI: designware: Add
default link up check if sub-driver doesn't override") to using both
LINK_IN_TRAINING and LINK_UP in commit 01c076732e82 ("PCI: designware:
Check LTSSM training bit before deciding link is up").

Given all that it seems that i.MX6 doesn't really need a special
.link_up() callback and imx6_pcie_link_up() can be dropped.

Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Leonard Crestez <leonard.crestez@nxp.com>
Cc: "A.s. Dong" <aisheng.dong@nxp.com>
Cc: Richard Zhu <hongxing.zhu@nxp.com>
Cc: linux-imx@nxp.com
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
---
 drivers/pci/controller/dwc/pci-imx6.c | 12 +-----------
 1 file changed, 1 insertion(+), 11 deletions(-)

Comments

Trent Piepho Dec. 21, 2018, 6:55 p.m. UTC | #1
On Thu, 2018-12-20 at 23:27 -0800, Andrey Smirnov wrote:
> Until commit 4d107d3b5a68 ("PCI: imx6: Move link up check into
> imx6_pcie_wait_for_link()") the driver relied on both LINK_UP and
> LINK_IN_TRAINING to determine if PCIE link was up.

I've already got a patch in that fixed this issue.  Queued for 4.19 and
4.14 stable.

The problem was created by 886bc5ceb5cc in one branch and by
4d107d3b5a68 on another branch, that when merged in 562df5c8521e, the
merge kept some pieces from each commit and dropped other pieces, which
resulted in this check getting dropped.
Andrey Smirnov Dec. 22, 2018, 12:39 a.m. UTC | #2
On Fri, Dec 21, 2018 at 10:55 AM Trent Piepho <tpiepho@impinj.com> wrote:
>
> On Thu, 2018-12-20 at 23:27 -0800, Andrey Smirnov wrote:
> > Until commit 4d107d3b5a68 ("PCI: imx6: Move link up check into
> > imx6_pcie_wait_for_link()") the driver relied on both LINK_UP and
> > LINK_IN_TRAINING to determine if PCIE link was up.
>
> I've already got a patch in that fixed this issue.  Queued for 4.19 and
> 4.14 stable.
>
> The problem was created by 886bc5ceb5cc in one branch and by
> 4d107d3b5a68 on another branch, that when merged in 562df5c8521e, the
> merge kept some pieces from each commit and dropped other pieces, which
> resulted in this check getting dropped.

OK, cool, this patch can be dropped then.

Thanks,
Andrey Smirnov
diff mbox series

Patch

diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index 937d630f8c9d..74faca11eeae 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -84,8 +84,6 @@  struct imx6_pcie {
 #define PL_OFFSET 0x700
 #define PCIE_PHY_DEBUG_R0 (PL_OFFSET + 0x28)
 #define PCIE_PHY_DEBUG_R1 (PL_OFFSET + 0x2c)
-#define PCIE_PHY_DEBUG_R1_XMLH_LINK_IN_TRAINING	(1 << 29)
-#define PCIE_PHY_DEBUG_R1_XMLH_LINK_UP		(1 << 4)
 
 #define PCIE_PHY_CTRL (PL_OFFSET + 0x114)
 #define PCIE_PHY_CTRL_DATA_LOC 0
@@ -732,12 +730,6 @@  static int imx6_pcie_host_init(struct pcie_port *pp)
 	return 0;
 }
 
-static int imx6_pcie_link_up(struct dw_pcie *pci)
-{
-	return dw_pcie_readl_dbi(pci, PCIE_PHY_DEBUG_R1) &
-			PCIE_PHY_DEBUG_R1_XMLH_LINK_UP;
-}
-
 static const struct dw_pcie_host_ops imx6_pcie_host_ops = {
 	.host_init = imx6_pcie_host_init,
 };
@@ -769,9 +761,7 @@  static int imx6_add_pcie_port(struct imx6_pcie *imx6_pcie,
 	return 0;
 }
 
-static const struct dw_pcie_ops dw_pcie_ops = {
-	.link_up = imx6_pcie_link_up,
-};
+static const struct dw_pcie_ops dw_pcie_ops;
 
 #ifdef CONFIG_PM_SLEEP
 static void imx6_pcie_ltssm_disable(struct device *dev)