PCI: imx6: Do not switch speed if Gen2 is disabled
Save a bit of time and avoid going through link speed change procedure in
configuration where link max speed is limited to Gen1 in DT.
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Cc: yurovsky@gmail.com
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Dong Aisheng <dongas86@gmail.com>
Cc: linux-arm-kernel@lists.infradead.org
diff --git a/drivers/pci/dwc/pci-imx6.c b/drivers/pci/dwc/pci-imx6.c
index 793b008..102edcf 100644
--- a/drivers/pci/dwc/pci-imx6.c
+++ b/drivers/pci/dwc/pci-imx6.c
@@ -533,40 +533,40 @@ static int imx6_pcie_establish_link(struct imx6_pcie *imx6_pcie)
tmp &= ~PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK;
tmp |= PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN2;
dw_pcie_writel_dbi(pci, PCIE_RC_LCR, tmp);
- } else {
- dev_info(dev, "Link: Gen2 disabled\n");
- }
- /*
- * Start Directed Speed Change so the best possible speed both link
- * partners support can be negotiated.
- */
- tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
- tmp |= PORT_LOGIC_SPEED_CHANGE;
- dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, tmp);
-
- if (imx6_pcie->variant != IMX7D) {
/*
- * On i.MX7, DIRECT_SPEED_CHANGE behaves differently
- * from i.MX6 family when no link speed transition
- * occurs and we go Gen1 -> yep, Gen1. The difference
- * is that, in such case, it will not be cleared by HW
- * which will cause the following code to report false
- * failure.
+ * Start Directed Speed Change so the best possible
+ * speed both link partners support can be negotiated.
*/
+ tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
+ tmp |= PORT_LOGIC_SPEED_CHANGE;
+ dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, tmp);
- ret = imx6_pcie_wait_for_speed_change(imx6_pcie);
+ if (imx6_pcie->variant != IMX7D) {
+ /*
+ * On i.MX7, DIRECT_SPEED_CHANGE behaves differently
+ * from i.MX6 family when no link speed transition
+ * occurs and we go Gen1 -> yep, Gen1. The difference
+ * is that, in such case, it will not be cleared by HW
+ * which will cause the following code to report false
+ * failure.
+ */
+
+ ret = imx6_pcie_wait_for_speed_change(imx6_pcie);
+ if (ret) {
+ dev_err(dev, "Failed to bring link up!\n");
+ goto err_reset_phy;
+ }
+ }
+
+ /* Make sure link training is finished as well! */
+ ret = imx6_pcie_wait_for_link(imx6_pcie);
if (ret) {
dev_err(dev, "Failed to bring link up!\n");
goto err_reset_phy;
}
- }
-
- /* Make sure link training is finished as well! */
- ret = imx6_pcie_wait_for_link(imx6_pcie);
- if (ret) {
- dev_err(dev, "Failed to bring link up!\n");
- goto err_reset_phy;
+ } else {
+ dev_info(dev, "Link: Gen2 disabled\n");
}
tmp = dw_pcie_readl_dbi(pci, PCIE_RC_LCSR);