PCI: mvebu: move clock enable before register access
The clock passed to PCI controller found on MVEBU SoCs may come from a
clock gate. This requires the clock to be enabled before any registers
are accessed. Therefore, move the clock enable before register iomap to
ensure it is enabled.
Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
diff --git a/drivers/pci/host/pci-mvebu.c b/drivers/pci/host/pci-mvebu.c
index 32ac564..5c327ce 100644
--- a/drivers/pci/host/pci-mvebu.c
+++ b/drivers/pci/host/pci-mvebu.c
@@ -897,11 +897,23 @@
continue;
}
+ port->clk = of_clk_get_by_name(child, NULL);
+ if (IS_ERR(port->clk)) {
+ dev_err(&pdev->dev, "PCIe%d.%d: cannot get clock\n",
+ port->port, port->lane);
+ continue;
+ }
+
+ ret = clk_prepare_enable(port->clk);
+ if (ret)
+ continue;
+
port->base = mvebu_pcie_map_registers(pdev, child, port);
if (IS_ERR(port->base)) {
dev_err(&pdev->dev, "PCIe%d.%d: cannot map registers\n",
port->port, port->lane);
port->base = NULL;
+ clk_disable_unprepare(port->clk);
continue;
}
@@ -917,22 +929,9 @@
port->port, port->lane);
}
- port->clk = of_clk_get_by_name(child, NULL);
- if (IS_ERR(port->clk)) {
- dev_err(&pdev->dev, "PCIe%d.%d: cannot get clock\n",
- port->port, port->lane);
- iounmap(port->base);
- port->haslink = 0;
- continue;
- }
-
port->dn = child;
-
- clk_prepare_enable(port->clk);
spin_lock_init(&port->conf_lock);
-
mvebu_sw_pci_bridge_init(port);
-
i++;
}