powerpc/mpc85xx: modify erratum A007186

T2080 v1.0 has this errata while v1.1 has fixed
this errata by hardware, add a new function has_errata_a007186
to check the SVR_SOC_VER, SVR_MAJ and SVR_MIN first,
if the sil has errata a007186, then run the errata code,
if not, doesn't run the code.

Signed-off-by: Zhao Qiang <B45475@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>
diff --git a/arch/powerpc/include/asm/fsl_errata.h b/arch/powerpc/include/asm/fsl_errata.h
index b9e2fb0..61c6d70 100644
--- a/arch/powerpc/include/asm/fsl_errata.h
+++ b/arch/powerpc/include/asm/fsl_errata.h
@@ -27,3 +27,27 @@
 }
 #endif
 #endif
+
+#ifdef CONFIG_SYS_FSL_ERRATUM_A007186
+static inline bool has_erratum_a007186(void)
+{
+	u32 svr = get_svr();
+	u32 soc = SVR_SOC_VER(svr);
+
+	switch (soc) {
+	case SVR_T4240:
+		return IS_SVR_REV(svr, 2, 0);
+	case SVR_T4160:
+		return IS_SVR_REV(svr, 2, 0);
+	case SVR_B4860:
+		return IS_SVR_REV(svr, 2, 0);
+	case SVR_B4420:
+		return IS_SVR_REV(svr, 2, 0);
+	case SVR_T2081:
+	case SVR_T2080:
+		return IS_SVR_REV(svr, 1, 0);
+	}
+
+	return false;
+}
+#endif