sbc8548: relocate 64MB user flash to sane boundary

The current situation has the 64MB user flash at an awkward
alignment; shifted back from 0xfc00_0000 by 8M, to leave an 8MB hole
for the soldered on boot flash @ EOM.  But to switch to optionally
supporting booting off the 64MB flash, the 64MB will then be mapped
at the sane address of 0xfc00_0000.

This leads to awkward things when programming the 64MB flash prior
to transitioning to it -- i.e. even though the chip spans from
0xfb80_0000 to 0xff7f_ffff, you would have to program a u-boot image
into the two sectors from 0xfbf0_0000 --> 0xfbff_ffff so that it was
in the right place when JP12/SW2.8 were switched to make the 64MB on
/CS0. (i.e. the chip is only looking at the bits in mask 0x3ff_ffff)

We also have to have three TLB entries responsible for dealing with
mapping the 64MB flash due to this 8MB of misalignment.

In the end, there is address space from 0xec00_0000 to 0xefff_ffff
where we can map it, and then the transition from booting from one
config to the other will be a simple 0xec --> 0xfc mapping.  Plus we
can toss out a TLB entry.

Note that TLB0 is kept at 64MB and not shrunk down to the 8MB boot
flash; this means we won't have to change it when the alternate
config uses the full 64MB for booting, in TLB0.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/include/configs/sbc8548.h b/include/configs/sbc8548.h
index 7c26207..cea0179 100644
--- a/include/configs/sbc8548.h
+++ b/include/configs/sbc8548.h
@@ -140,7 +140,7 @@
  * FLASH on the Local Bus
  * Two banks, one 8MB the other 64MB, using the CFI driver.
  * Boot from BR0/OR0 bank at 0xff80_0000
- * Alternate BR6/OR6 bank at 0xfb80_0000
+ * Alternate BR6/OR6 bank at 0xec00_0000
  *
  * BR0:
  *    Base address 0 = 0xff80_0000 = BR0[0:16] = 1111 1111 1000 0000 0
@@ -152,13 +152,13 @@
  * 1111 1111 1000 0000 0000 1000 0000 0001 = ff800801    BR0
  *
  * BR6:
- *    Base address 6 = 0xfb80_0000 = BR6[0:16] = 1111 1011 1000 0000 0
+ *    Base address 6 = 0xec00_0000 = BR6[0:16] = 1110 1100 0000 0000 0
  *    Port Size = 32 bits = BRx[19:20] = 11
  *    Use GPCM = BRx[24:26] = 000
  *    Valid = BRx[31] = 1
  *
  * 0    4    8    12   16   20   24   28
- * 1111 1011 1000 0000 0001 1000 0000 0001 = fb801801    BR6
+ * 1110 1100 0000 0000 0001 1000 0000 0001 = ec001801    BR6
  *
  * OR0:
  *    Addr Mask = 8M = OR1[0:16] = 1111 1111 1000 0000 0
@@ -186,11 +186,11 @@
  */
 
 #define CONFIG_SYS_BOOT_BLOCK		0xff800000	/* start of 8MB Flash */
-#define CONFIG_SYS_ALT_FLASH		0xfb800000	/* 64MB "user" flash */
+#define CONFIG_SYS_ALT_FLASH		0xec000000	/* 64MB "user" flash */
 #define CONFIG_SYS_FLASH_BASE		CONFIG_SYS_BOOT_BLOCK	/* start of FLASH 16M */
 
 #define CONFIG_SYS_BR0_PRELIM		0xff800801
-#define CONFIG_SYS_BR6_PRELIM		0xfb801801
+#define CONFIG_SYS_BR6_PRELIM		0xec001801
 
 #define	CONFIG_SYS_OR0_PRELIM		0xff806e65
 #define	CONFIG_SYS_OR6_PRELIM		0xfc006e65