powerpc/mpc85xx: Add Differential SYSCLK config support T1040

Adds support for clock sourcing from sysclk(100MHz) for usb
on T104xRDB and T1040QDS. This requires changing reference divisor
and multiplication factor to derive usb clock from sysclk.
Signed-off-by: Nikhil Badola <nikhil.badola@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>

arch/powerpc/cpu/mpc85xx/cpu_init.c

@@ -39,6 +39,29 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
+#ifdef CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
+/*
+ * For deriving usb clock from 100MHz sysclk, reference divisor is set
+ * to a value of 5, which gives an intermediate value 20(100/5). The
+ * multiplication factor integer is set to 24, which when multiplied to
+ * above intermediate value provides clock for usb ip.
+ */
+void usb_single_source_clk_configure(struct ccsr_usb_phy *usb_phy)
+{
+	sys_info_t sysinfo;
+
+	get_sys_info(&sysinfo);
+	if (sysinfo.diff_sysclk == 1) {
+		clrbits_be32(&usb_phy->pllprg[1],
+			     CONFIG_SYS_FSL_USB_PLLPRG2_MFI);
+		setbits_be32(&usb_phy->pllprg[1],
+			     CONFIG_SYS_FSL_USB_PLLPRG2_REF_DIV_INTERNAL_CLK |
+			     CONFIG_SYS_FSL_USB_PLLPRG2_MFI_INTERNAL_CLK |
+			     CONFIG_SYS_FSL_USB_INTERNAL_SOC_CLK_EN);
+		}
+}
+#endif
+
 #ifdef CONFIG_SYS_FSL_ERRATUM_A006261
 void fsl_erratum_a006261_workaround(struct ccsr_usb_phy __iomem *usb_phy)
 {
@@ -815,6 +838,9 @@ skip_l2:
 			     CONFIG_SYS_FSL_USB_PLLPRG2_PHY1_CLK_EN |
 			     CONFIG_SYS_FSL_USB_PLLPRG2_MFI |
 			     CONFIG_SYS_FSL_USB_PLLPRG2_PLL_EN);
+#ifdef CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
+		usb_single_source_clk_configure(usb_phy);
+#endif
 		setbits_be32(&usb_phy->port1.ctrl,
 			     CONFIG_SYS_FSL_USB_CTRL_PHY_EN);
 		setbits_be32(&usb_phy->port1.drvvbuscfg,

include/fsl_usb.h

@@ -48,6 +48,11 @@ struct ccsr_usb_phy {
 #define CONFIG_SYS_FSL_USB_PLLPRG2_PHY2_CLK_EN (1 << 0)
 #define CONFIG_SYS_FSL_USB_PLLPRG2_PHY1_CLK_EN (1 << 1)
 #define CONFIG_SYS_FSL_USB_PLLPRG2_FRAC_LPF_EN (1 << 13)
+#ifdef CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
+#define CONFIG_SYS_FSL_USB_PLLPRG2_REF_DIV_INTERNAL_CLK (5 << 4)
+#define CONFIG_SYS_FSL_USB_PLLPRG2_MFI_INTERNAL_CLK (6 << 16)
+#define CONFIG_SYS_FSL_USB_INTERNAL_SOC_CLK_EN (1 << 20)
+#endif
 #define CONFIG_SYS_FSL_USB_PLLPRG2_REF_DIV (1 << 4)
 #define CONFIG_SYS_FSL_USB_PLLPRG2_MFI (5 << 16)
 #define CONFIG_SYS_FSL_USB_PLLPRG2_PLL_EN (1 << 21)