85xx: Speed up get_ddr_freq() and get_bus_freq()

get_ddr_freq() and get_bus_freq() used get_sys_info() each time they were
called.  However, get_sys_info() recalculates extraneous information when
called each time.  Have get_ddr_freq() and get_bus_freq() return memoized
values from global_data instead.

Signed-off-by: James Yang <James.Yang@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/cpu/mpc85xx/speed.c b/cpu/mpc85xx/speed.c
index 952f30c..d90d397 100644
--- a/cpu/mpc85xx/speed.c
+++ b/cpu/mpc85xx/speed.c
@@ -48,6 +48,8 @@
 	 * overflow for processor speeds above 2GHz */
 	half_freqSystemBus = sysInfo->freqSystemBus/2;
 	sysInfo->freqProcessor = e500_ratio*half_freqSystemBus;
+
+	/* Note: freqDDRBus is the MCLK frequency, not the data rate. */
 	sysInfo->freqDDRBus = sysInfo->freqSystemBus;
 
 #ifdef CONFIG_DDR_CLK_FREQ
@@ -75,6 +77,7 @@
 	get_sys_info (&sys_info);
 	gd->cpu_clk = sys_info.freqProcessor;
 	gd->bus_clk = sys_info.freqSystemBus;
+	gd->mem_clk = sys_info.freqDDRBus;
 	gd->i2c1_clk = sys_info.freqSystemBus;
 	gd->i2c2_clk = sys_info.freqSystemBus;
 
@@ -96,14 +99,7 @@
  *********************************************/
 ulong get_bus_freq (ulong dummy)
 {
-	ulong val;
-
-	sys_info_t sys_info;
-
-	get_sys_info (&sys_info);
-	val = sys_info.freqSystemBus;
-
-	return val;
+	return gd->bus_clk;
 }
 
 /********************************************
@@ -112,12 +108,5 @@
  *********************************************/
 ulong get_ddr_freq (ulong dummy)
 {
-	ulong val;
-
-	sys_info_t sys_info;
-
-	get_sys_info (&sys_info);
-	val = sys_info.freqDDRBus;
-
-	return val;
+	return gd->mem_clk;
 }