[PATCH 3.16 003/217] PCI: imx6: Move PHY reset into imx6_pcie_establish_link()

From: Ben Hutchings
Date: Tue Apr 26 2016 - 19:16:19 EST


3.16.35-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: Lucas Stach <l.stach@xxxxxxxxxxxxxx>

commit 54a47a83421a3b7ee0e0fab7f65d04179bdf59b6 upstream.

This adds the PHY reset into a common error path of
imx6_pcie_establish_link(), deduplicating some of the debug prints. Also
reduce the severity of the "no-link" message in the one place where it is
expected to be hit when no peripheral is attached.

Signed-off-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
[bwh: Backported to 3.16:
- Error paths were different in imx6_pcie_start_link()
- Adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/pci/host/pci-imx6.c | 28 +++++++++++++++-------------
1 file changed, 15 insertions(+), 13 deletions(-)

--- a/drivers/pci/host/pci-imx6.c
+++ b/drivers/pci/host/pci-imx6.c
@@ -305,10 +305,6 @@ static int imx6_pcie_wait_for_link(struc
if (--count)
continue;

- dev_err(pp->dev, "phy link never came up\n");
- dev_dbg(pp->dev, "DEBUG_R0: 0x%08x, DEBUG_R1: 0x%08x\n",
- readl(pp->dbi_base + PCIE_PHY_DEBUG_R0),
- readl(pp->dbi_base + PCIE_PHY_DEBUG_R1));
return -EINVAL;
}

@@ -343,8 +339,10 @@ static int imx6_pcie_start_link(struct p
IMX6Q_GPR12_PCIE_CTL_2, 1 << 10);

ret = imx6_pcie_wait_for_link(pp);
- if (ret)
- return ret;
+ if (ret) {
+ dev_info(pp->dev, "Link never came up\n");
+ goto err_reset_phy;
+ }

/* Allow Gen2 mode after the link is up. */
tmp = readl(pp->dbi_base + PCIE_RC_LCR);
@@ -377,12 +375,21 @@ static int imx6_pcie_start_link(struct p

if (ret) {
dev_err(pp->dev, "Failed to bring link up!\n");
+ goto err_reset_phy;
} else {
tmp = readl(pp->dbi_base + 0x80);
dev_dbg(pp->dev, "Link up, Gen=%i\n", (tmp >> 16) & 0xf);
}

return ret;
+
+err_reset_phy:
+ dev_dbg(pp->dev, "PHY DEBUG_R0=0x%08x DEBUG_R1=0x%08x\n",
+ readl(pp->dbi_base + PCIE_PHY_DEBUG_R0),
+ readl(pp->dbi_base + PCIE_PHY_DEBUG_R1));
+ imx6_pcie_reset_phy(pp);
+
+ return ret;
}

static void imx6_pcie_host_init(struct pcie_port *pp)
@@ -470,11 +477,6 @@ static int imx6_pcie_link_up(struct pcie
if ((debug_r0 & 0x3f) != 0x0d)
return 0;

- dev_err(pp->dev, "transition to gen2 is stuck, reset PHY!\n");
- dev_dbg(pp->dev, "debug_r0=%08x debug_r1=%08x\n", debug_r0, rc);
-
- imx6_pcie_reset_phy(pp);
-
return 0;
}