powerpc/mpc85xx: Add DSP side awareness for Freescale Heterogeneous SoCs

The code provides framework for heterogeneous multicore chips based on StarCore
and Power Architecture which are chasis-2 compliant, like B4860 and B4420

It will make u-boot recognize all non-ppc cores and peripherals like
SC3900/DSP CPUs, MAPLE, CPRI and print their configuration in u-boot logs.
Example boot logs of B4860QDS:

U-Boot 2015.01-00232-geef6e36-dirty (Jan 19 2015 - 11:58:45)

CPU0:  B4860E, Version: 2.2, (0x86880022)
Core:  e6500, Version: 2.0, (0x80400120)
Clock Configuration:
       CPU0:1600 MHz, CPU1:1600 MHz, CPU2:1600 MHz, CPU3:1600 MHz,
       DSP CPU0:1200 MHz, DSP CPU1:1200 MHz, DSP CPU2:1200 MHz, DSP CPU3:1200 MHz,
       DSP CPU4:1200 MHz, DSP CPU5:1200 MHz,
       CCB:666.667 MHz,
       DDR:933.333 MHz (1866.667 MT/s data rate) (Asynchronous), IFC:166.667 MHz
       CPRI:600  MHz
       MAPLE:600  MHz, MAPLE-ULB:800  MHz, MAPLE-eTVPE:1000 MHz
       FMAN1: 666.667 MHz
       QMAN:  333.333 MHz

Top level changes include:
(1) Top level CONFIG to identify HETEROGENUOUS clusters
(2) CONFIGS for SC3900/DSP components
(3) Global structures like "cpu_type" and "MPC85xx_SYS_INFO"
    updated for dsp cores and other components
(3) APIs to get DSP num cores and their Mask like:
        cpu_dsp_mask, cpu_num_dspcores etc same as that of PowerPC
(5) Code to fetch and print SC cores and other heterogenous
    device's frequencies
(6) README added for the same

Signed-off-by: Shaveta Leekha <shaveta@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>
diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h
index db8cc8c..fdfca90 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -1202,12 +1202,17 @@
 	u32 soc_ver;
 	u32 num_cores;
 	u32 mask;	/* which cpu(s) actually exist */
+#ifdef CONFIG_HETROGENOUS_CLUSTERS
+	u32 dsp_num_cores;
+	u32 dsp_mask;	/* which DSP cpu(s) actually exist */
+#endif
 };
 
 struct cpu_type *identify_cpu(u32 ver);
 int fixup_cpu(void);
 
 int fsl_qoriq_core_to_cluster(unsigned int core);
+int fsl_qoriq_dsp_core_to_cluster(unsigned int core);
 
 #if defined(CONFIG_MPC85xx) || defined(CONFIG_MPC86xx)
 #define CPU_TYPE_ENTRY(n, v, nc) \