MIPS: BCM63XX: add and use a clock for PCIe

Add a PCIe clock and use that instead of directly touching the clock
control register. While at it, fail if there is no such clock.

Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
Acked-by: Florian Fainelli <florian@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/4452
Signed-off-by: John Crispin <blogic@openwrt.org>
diff --git a/arch/mips/bcm63xx/clk.c b/arch/mips/bcm63xx/clk.c
index dff79ab..89a5fb0 100644
--- a/arch/mips/bcm63xx/clk.c
+++ b/arch/mips/bcm63xx/clk.c
@@ -253,6 +253,19 @@
 };
 
 /*
+ * PCIe clock
+ */
+
+static void pcie_set(struct clk *clk, int enable)
+{
+	bcm_hwclock_set(CKCTL_6328_PCIE_EN, enable);
+}
+
+static struct clk clk_pcie = {
+	.set	= pcie_set,
+};
+
+/*
  * Internal peripheral clock
  */
 static struct clk clk_periph = {
@@ -313,6 +326,8 @@
 		return &clk_pcm;
 	if (BCMCPU_IS_6368() && !strcmp(id, "ipsec"))
 		return &clk_ipsec;
+	if (BCMCPU_IS_6328() && !strcmp(id, "pcie"))
+		return &clk_pcie;
 	return ERR_PTR(-ENOENT);
 }