ARM: omap3: Implement dpll5 (HSUSB clk) workaround for OMAP36xx/AM/DM37xx according to errata sprz318e.

In chapter 'Advisory 2.1 USB Host Clock Drift Causes USB Spec Non-compliance in Certain Configurations' of the TI Errata it is recommended to use certain div/mult values for the DPLL5 clock setup.
So far u-boot used the old 34xx values, so I added the errata recommended values specificly for 36xx init only.
Also, the FSEL registers exist no longer, so removed them from init.

Tested this on a AM3703 board with 19.2MHz oscillator, which previously couldnt lock the dpll5 (kernel complained). As a consequence the EHCI USB port wasnt usable in U-Boot and kernel. With this patch, kernel panics disappear and USB working fine in u-boot and kernel.

Signed-off-by: Andreas Naumann <anaumann@ultratronik.de>
[trini: Add extern to <asm/arch-omap3/clock.h>
Signed-off-by: Tom Rini <trini@ti.com>
diff --git a/arch/arm/include/asm/arch-omap3/clocks_omap3.h b/arch/arm/include/asm/arch-omap3/clocks_omap3.h
index bf7fa00..df73c4b 100644
--- a/arch/arm/include/asm/arch-omap3/clocks_omap3.h
+++ b/arch/arm/include/asm/arch-omap3/clocks_omap3.h
@@ -323,4 +323,26 @@
 #define PER_36XX_FSEL_38P4	0x07
 #define PER_36XX_M2_38P4	0x09
 
+/* 36XX PER2 DPLL */
+
+#define PER2_36XX_M_12		0x50
+#define PER2_36XX_N_12		0x00
+#define PER2_36XX_M2_12		0x08
+
+#define PER2_36XX_M_13		0x1BB
+#define PER2_36XX_N_13		0x05
+#define PER2_36XX_M2_13		0x08
+
+#define PER2_36XX_M_19P2		0x32
+#define PER2_36XX_N_19P2		0x00
+#define PER2_36XX_M2_19P2		0x08
+
+#define PER2_36XX_M_26		0x1BB
+#define PER2_36XX_N_26		0x0B
+#define PER2_36XX_M2_26		0x08
+
+#define PER2_36XX_M_38P4		0x19
+#define PER2_36XX_N_38P4		0x00
+#define PER2_36XX_M2_38P4		0x08
+
 #endif	/* endif _CLOCKS_OMAP3_H_ */