diff --git a/arch/powerpc/include/asm/fixmap.h b/arch/powerpc/include/asm/fixmap.h
index 90f604b..d7dd8fb 100644
--- a/arch/powerpc/include/asm/fixmap.h
+++ b/arch/powerpc/include/asm/fixmap.h
@@ -51,6 +51,13 @@ enum fixed_addresses {
 	FIX_KMAP_BEGIN,	/* reserved pte's for temporary kernel mappings */
 	FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
 #endif
+#ifdef CONFIG_PPC_8xx
+	/* For IMMR we need an aligned 512K area */
+	FIX_IMMR_START,
+	FIX_IMMR_TOP = (FIX_IMMR_START - 1 + ((512 * 1024) / PAGE_SIZE)) &
+		       ~(((512 * 1024) / PAGE_SIZE) - 1),
+	FIX_IMMR_BASE = FIX_IMMR_TOP - 1 + ((512 * 1024) / PAGE_SIZE),
+#endif
 	/* FIX_PCIE_MCFG, */
 	__end_of_fixed_addresses
 };
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 07cebc3..9724ff8 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -68,6 +68,10 @@
 #include "../mm/mmu_decl.h"
 #endif
 
+#ifdef CONFIG_PPC_8xx
+#include <asm/fixmap.h>
+#endif
+
 int main(void)
 {
 	DEFINE(THREAD, offsetof(struct task_struct, thread));
@@ -772,5 +776,9 @@ int main(void)
 
 	DEFINE(PPC_DBELL_SERVER, PPC_DBELL_SERVER);
 
+#ifdef CONFIG_PPC_8xx
+	DEFINE(VIRT_IMMR_BASE, __fix_to_virt(FIX_IMMR_BASE));
+#endif
+
 	return 0;
 }
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 87d1f5f..09173ae 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -30,6 +30,7 @@
 #include <asm/ppc_asm.h>
 #include <asm/asm-offsets.h>
 #include <asm/ptrace.h>
+#include <asm/fixmap.h>
 
 /* Macro to make the code more readable. */
 #ifdef CONFIG_8xx_CPU6
@@ -763,7 +764,7 @@ start_here:
  * virtual to physical.  Also, set the cache mode since that is defined
  * by TLB entries and perform any additional mapping (like of the IMMR).
  * If configured to pin some TLBs, we pin the first 8 Mbytes of kernel,
- * 24 Mbytes of data, and the 8M IMMR space.  Anything not covered by
+ * 24 Mbytes of data, and the 512k IMMR space.  Anything not covered by
  * these mappings is mapped by page tables.
  */
 initial_mmu:
@@ -812,7 +813,7 @@ initial_mmu:
 	ori	r8, r8, MD_APG_INIT@l
 	mtspr	SPRN_MD_AP, r8
 
-	/* Map another 8 MByte at the IMMR to get the processor
+	/* Map a 512k page for the IMMR to get the processor
 	 * internal registers (among other things).
 	 */
 #ifdef CONFIG_PIN_TLB
@@ -820,12 +821,12 @@ initial_mmu:
 	mtspr	SPRN_MD_CTR, r10
 #endif
 	mfspr	r9, 638			/* Get current IMMR */
-	andis.	r9, r9, 0xff80		/* Get 8Mbyte boundary */
+	andis.	r9, r9, 0xfff8		/* Get 512 kbytes boundary */
 
-	mr	r8, r9			/* Create vaddr for TLB */
+	lis	r8, VIRT_IMMR_BASE@h	/* Create vaddr for TLB */
 	ori	r8, r8, MD_EVALID	/* Mark it valid */
 	mtspr	SPRN_MD_EPN, r8
-	li	r8, MD_PS8MEG		/* Set 8M byte page */
+	li	r8, MD_PS512K | MD_GUARDED	/* Set 512k byte page */
 	ori	r8, r8, MD_SVALID	/* Make it valid */
 	mtspr	SPRN_MD_TWC, r8
 	mr	r8, r9			/* Create paddr for TLB */
diff --git a/arch/powerpc/mm/mmu_decl.h b/arch/powerpc/mm/mmu_decl.h
index 40dd5d3..e7228b7 100644
--- a/arch/powerpc/mm/mmu_decl.h
+++ b/arch/powerpc/mm/mmu_decl.h
@@ -107,6 +107,13 @@ struct hash_pte;
 extern struct hash_pte *Hash, *Hash_end;
 extern unsigned long Hash_size, Hash_mask;
 
+#define PHYS_IMMR_BASE (mfspr(SPRN_IMMR) & 0xfff80000)
+#ifdef CONFIG_PPC_8xx
+#define VIRT_IMMR_BASE (__fix_to_virt(FIX_IMMR_BASE))
+#else
+#define VIRT_IMMR_BASE PHYS_IMMR_BASE
+#endif
+
 #endif /* CONFIG_PPC32 */
 
 #ifdef CONFIG_PPC64
diff --git a/arch/powerpc/sysdev/cpm_common.c b/arch/powerpc/sysdev/cpm_common.c
index 9d32465..94476f4 100644
--- a/arch/powerpc/sysdev/cpm_common.c
+++ b/arch/powerpc/sysdev/cpm_common.c
@@ -28,6 +28,7 @@
 #include <asm/udbg.h>
 #include <asm/io.h>
 #include <asm/cpm.h>
+#include <asm/fixmap.h>
 #include <soc/fsl/qe/qe.h>
 
 #include <mm/mmu_decl.h>
@@ -37,12 +38,16 @@
 #endif
 
 #ifdef CONFIG_PPC_EARLY_DEBUG_CPM
-static u32 __iomem *cpm_udbg_txdesc =
-	(u32 __iomem __force *)CONFIG_PPC_EARLY_DEBUG_CPM_ADDR;
+static u32 __iomem *cpm_udbg_txdesc;
 
 static void udbg_putc_cpm(char c)
 {
-	u8 __iomem *txbuf = (u8 __iomem __force *)in_be32(&cpm_udbg_txdesc[1]);
+	static u8 __iomem *txbuf;
+
+	if (unlikely(txbuf == NULL))
+		txbuf = (u8 __iomem __force *)
+			 (in_be32(&cpm_udbg_txdesc[1]) - PHYS_IMMR_BASE +
+			  VIRT_IMMR_BASE);
 
 	if (c == '\n')
 		udbg_putc_cpm('\r');
@@ -56,6 +61,10 @@ static void udbg_putc_cpm(char c)
 
 void __init udbg_init_cpm(void)
 {
+	cpm_udbg_txdesc = (u32 __iomem __force *)
+			  (CONFIG_PPC_EARLY_DEBUG_CPM_ADDR - PHYS_IMMR_BASE +
+			   VIRT_IMMR_BASE);
+
 	if (cpm_udbg_txdesc) {
 #ifdef CONFIG_CPM2
 		setbat(1, 0xf0000000, 0xf0000000, 1024*1024, PAGE_KERNEL_NCG);
