CLK: ti: dra7: Initialize USB_DPLL

USB_DPLL must be initialized and locked at boot so that
USB modules can work.

Also program USB_DLL_M2 output to half rate.

CC: Mike Turquette <mturquette@linaro.org>
CC: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Tero Kristo <t-kristo@ti.com>

drivers/clk/ti/clk-7xx.c

@@ -18,6 +18,7 @@
 
 #define DRA7_DPLL_ABE_DEFFREQ				361267200
 #define DRA7_DPLL_GMAC_DEFFREQ				1000000000
+#define DRA7_DPLL_USB_DEFFREQ				960000000
 
 
 static struct ti_dt_clk dra7xx_clks[] = {
@@ -327,5 +328,15 @@ int __init dra7xx_dt_clk_init(void)
 	if (rc)
 		pr_err("%s: failed to configure GMAC DPLL!\n", __func__);
 
+	dpll_ck = clk_get_sys(NULL, "dpll_usb_ck");
+	rc = clk_set_rate(dpll_ck, DRA7_DPLL_USB_DEFFREQ);
+	if (rc)
+		pr_err("%s: failed to configure USB DPLL!\n", __func__);
+
+	dpll_ck = clk_get_sys(NULL, "dpll_usb_m2_ck");
+	rc = clk_set_rate(dpll_ck, DRA7_DPLL_USB_DEFFREQ/2);
+	if (rc)
+		pr_err("%s: failed to set USB_DPLL M2 OUT\n", __func__);
+
 	return rc;
 }