[PATCH v2] microblaze: Remove noMMU code

* [PATCH v2] microblaze: Remove noMMU code
@ 2020-11-26 13:32 Michal Simek
  2020-11-26 14:38 ` Mike Rapoport
                   ` (2 more replies)
  0 siblings, 3 replies; 4+ messages in thread
From: Michal Simek @ 2020-11-26 13:32 UTC (permalink / raw)
  To: linux-kernel, monstr, michal.simek, git
  Cc: Mike Rapoport, Arnd Bergmann, Andrew Morton, Anshuman Khandual,
	Arvind Sankar, Baoquan He, Christian Brauner, Dmitry Safonov,
	Eric Biggers, Geert Uytterhoeven, Greentime Hu,
	Gustavo A. R. Silva, Helge Deller, Herbert Xu, Ira Weiny,
	Jens Axboe, Joe Perches, Manish Narani, Oleg Nesterov,
	Pekka Enberg, Peter Zijlstra (Intel),
	Randy Dunlap, Rob Herring, Robin Murphy,
	Sebastian Andrzej Siewior, Shubhrajyoti Datta, Stefan Asserhall,
	Steven Rostedt (VMware),
	Thomas Gleixner

This configuration is obsolete and likely none is really using it. That's
why remove it to simplify code.

Note about CONFIG_MMU in hw_exception_handler.S is left intentionally
for better comment understanding.

Cc: Mike Rapoport <rppt@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
---

Changes in v2:
- Remove also configs around CONFIG_MICROBLAZE_X_PAGES

If anybody is using this configuration please let me know.

---
 arch/microblaze/Kconfig                       |  53 +-
 arch/microblaze/Makefile                      |  11 +-
 arch/microblaze/configs/mmu_defconfig         |   1 -
 arch/microblaze/configs/nommu_defconfig       |  90 ---
 arch/microblaze/include/asm/dma.h             |   6 -
 arch/microblaze/include/asm/exceptions.h      |   5 -
 arch/microblaze/include/asm/io.h              |   3 -
 arch/microblaze/include/asm/mmu.h             |   4 -
 arch/microblaze/include/asm/mmu_context.h     |   4 -
 arch/microblaze/include/asm/page.h            |  59 --
 arch/microblaze/include/asm/pgalloc.h         |   4 -
 arch/microblaze/include/asm/pgtable.h         |  43 --
 arch/microblaze/include/asm/processor.h       |  37 --
 arch/microblaze/include/asm/registers.h       |   2 -
 arch/microblaze/include/asm/setup.h           |   2 -
 arch/microblaze/include/asm/tlbflush.h        |  14 -
 arch/microblaze/include/asm/uaccess.h         |  27 -
 arch/microblaze/kernel/Makefile               |   4 +-
 arch/microblaze/kernel/asm-offsets.c          |   2 -
 arch/microblaze/kernel/entry-nommu.S          | 622 ------------------
 arch/microblaze/kernel/exceptions.c           |   5 -
 arch/microblaze/kernel/head.S                 |  12 -
 arch/microblaze/kernel/hw_exception_handler.S | 130 +---
 arch/microblaze/kernel/microblaze_ksyms.c     |   2 -
 arch/microblaze/kernel/process.c              |  10 -
 arch/microblaze/kernel/setup.c                |   2 -
 arch/microblaze/kernel/signal.c               |   7 -
 arch/microblaze/kernel/unwind.c               |  19 -
 arch/microblaze/mm/Makefile                   |   2 +-
 arch/microblaze/mm/consistent.c               |  29 -
 arch/microblaze/mm/init.c                     |  49 --
 arch/microblaze/pci/pci-common.c              |   2 -
 32 files changed, 11 insertions(+), 1251 deletions(-)
 delete mode 100644 arch/microblaze/configs/nommu_defconfig
 delete mode 100644 arch/microblaze/kernel/entry-nommu.S

diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig
index 33925ffed68f..32739ab2af25 100644
--- a/arch/microblaze/Kconfig
+++ b/arch/microblaze/Kconfig
@@ -3,19 +3,17 @@ config MICROBLAZE
 	def_bool y
 	select ARCH_32BIT_OFF_T
 	select ARCH_NO_SWAP
-	select ARCH_HAS_BINFMT_FLAT if !MMU
 	select ARCH_HAS_DMA_PREP_COHERENT
 	select ARCH_HAS_GCOV_PROFILE_ALL
 	select ARCH_HAS_SYNC_DMA_FOR_CPU
 	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
-	select ARCH_HAS_DMA_SET_UNCACHED if !MMU
 	select ARCH_MIGHT_HAVE_PC_PARPORT
 	select ARCH_WANT_IPC_PARSE_VERSION
 	select BUILDTIME_TABLE_SORT
 	select TIMER_OF
 	select CLONE_BACKWARDS3
 	select COMMON_CLK
-	select DMA_DIRECT_REMAP if MMU
+	select DMA_DIRECT_REMAP
 	select GENERIC_ATOMIC64
 	select GENERIC_CLOCKEVENTS
 	select GENERIC_CPU_DEVICES
@@ -45,7 +43,7 @@ config MICROBLAZE
 	select TRACING_SUPPORT
 	select VIRT_TO_BUS
 	select CPU_NO_EFFICIENT_FFS
-	select MMU_GATHER_NO_RANGE if MMU
+	select MMU_GATHER_NO_RANGE
 	select SPARSE_IRQ
 	select SET_FS
 
@@ -96,8 +94,7 @@ menu "Processor type and features"
 source "kernel/Kconfig.hz"
 
 config MMU
-	bool "MMU support"
-	default n
+	def_bool y
 
 comment "Boot options"
 
@@ -143,18 +140,8 @@ config ADVANCED_OPTIONS
 comment "Default settings for advanced configuration options are used"
 	depends on !ADVANCED_OPTIONS
 
-config XILINX_UNCACHED_SHADOW
-	bool "Are you using uncached shadow for RAM ?"
-	depends on ADVANCED_OPTIONS && !MMU
-	default n
-	help
-	  This is needed to be able to allocate uncachable memory regions.
-	  The feature requires the design to define the RAM memory controller
-	  window to be twice as large as the actual physical memory.
-
 config HIGHMEM
 	bool "High memory support"
-	depends on MMU
 	help
 	  The address space of Microblaze processors is only 4 Gigabytes large
 	  and it has to accommodate user address space, kernel address
@@ -167,7 +154,7 @@ config HIGHMEM
 
 config LOWMEM_SIZE_BOOL
 	bool "Set maximum low memory"
-	depends on ADVANCED_OPTIONS && MMU
+	depends on ADVANCED_OPTIONS
 	help
 	  This option allows you to set the maximum amount of memory which
 	  will be used as "low memory", that is, memory which the kernel can
@@ -205,12 +192,11 @@ config KERNEL_START_BOOL
 
 config KERNEL_START
 	hex "Virtual address of kernel base" if KERNEL_START_BOOL
-	default "0xc0000000" if MMU
-	default KERNEL_BASE_ADDR if !MMU
+	default "0xc0000000"
 
 config TASK_SIZE_BOOL
 	bool "Set custom user task size"
-	depends on ADVANCED_OPTIONS && MMU
+	depends on ADVANCED_OPTIONS
 	help
 	  This option allows you to set the amount of virtual address space
 	  allocated to user tasks.  This can be useful in optimizing the
@@ -222,33 +208,6 @@ config TASK_SIZE
 	hex "Size of user task space" if TASK_SIZE_BOOL
 	default "0x80000000"
 
-choice
-	prompt "Page size"
-	default MICROBLAZE_4K_PAGES
-	depends on ADVANCED_OPTIONS && !MMU
-	help
-	  Select the kernel logical page size. Increasing the page size
-	  will reduce software overhead at each page boundary, allow
-	  hardware prefetch mechanisms to be more effective, and allow
-	  larger dma transfers increasing IO efficiency and reducing
-	  overhead. However the utilization of memory will increase.
-	  For example, each cached file will using a multiple of the
-	  page size to hold its contents and the difference between the
-	  end of file and the end of page is wasted.
-
-	  If unsure, choose 4K_PAGES.
-
-config MICROBLAZE_4K_PAGES
-	bool "4k page size"
-
-config MICROBLAZE_16K_PAGES
-	bool "16k page size"
-
-config MICROBLAZE_64K_PAGES
-	bool "64k page size"
-
-endchoice
-
 endmenu
 
 menu "Bus Options"
diff --git a/arch/microblaze/Makefile b/arch/microblaze/Makefile
index 7b340a35b194..bb980891816d 100644
--- a/arch/microblaze/Makefile
+++ b/arch/microblaze/Makefile
@@ -1,11 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 KBUILD_DEFCONFIG := mmu_defconfig
 
-ifeq ($(CONFIG_MMU),y)
 UTS_SYSNAME = -DUTS_SYSNAME=\"Linux\"
-else
-UTS_SYSNAME = -DUTS_SYSNAME=\"uClinux\"
-endif
 
 # What CPU vesion are we building for, and crack it open
 # as major.minor.rev
@@ -67,12 +63,7 @@ DTB:=$(subst simpleImage.,,$(filter simpleImage.%, $(MAKECMDGOALS)))
 
 core-y	+= $(boot)/dts/
 
-# defines filename extension depending memory management type
-ifeq ($(CONFIG_MMU),)
-MMU := -nommu
-endif
-
-export MMU DTB
+export DTB
 
 all: linux.bin
 
diff --git a/arch/microblaze/configs/mmu_defconfig b/arch/microblaze/configs/mmu_defconfig
index 9b8a50f30662..51337fffb947 100644
--- a/arch/microblaze/configs/mmu_defconfig
+++ b/arch/microblaze/configs/mmu_defconfig
@@ -16,7 +16,6 @@ CONFIG_XILINX_MICROBLAZE0_USE_DIV=1
 CONFIG_XILINX_MICROBLAZE0_USE_HW_MUL=2
 CONFIG_XILINX_MICROBLAZE0_USE_FPU=2
 CONFIG_HZ_100=y
-CONFIG_MMU=y
 CONFIG_CMDLINE_BOOL=y
 CONFIG_CMDLINE_FORCE=y
 CONFIG_HIGHMEM=y
diff --git a/arch/microblaze/configs/nommu_defconfig b/arch/microblaze/configs/nommu_defconfig
deleted file mode 100644
index 8c420782d6e4..000000000000
--- a/arch/microblaze/configs/nommu_defconfig
+++ /dev/null
@@ -1,90 +0,0 @@
-CONFIG_SYSVIPC=y
-CONFIG_POSIX_MQUEUE=y
-CONFIG_AUDIT=y
-CONFIG_BSD_PROCESS_ACCT=y
-CONFIG_BSD_PROCESS_ACCT_V3=y
-CONFIG_IKCONFIG=y
-CONFIG_IKCONFIG_PROC=y
-CONFIG_SYSFS_DEPRECATED=y
-CONFIG_SYSFS_DEPRECATED_V2=y
-# CONFIG_BASE_FULL is not set
-CONFIG_KALLSYMS_ALL=y
-CONFIG_EMBEDDED=y
-CONFIG_SLAB=y
-CONFIG_XILINX_MICROBLAZE0_USE_MSR_INSTR=1
-CONFIG_XILINX_MICROBLAZE0_USE_PCMP_INSTR=1
-CONFIG_XILINX_MICROBLAZE0_USE_BARREL=1
-CONFIG_XILINX_MICROBLAZE0_USE_DIV=1
-CONFIG_XILINX_MICROBLAZE0_USE_HW_MUL=2
-CONFIG_XILINX_MICROBLAZE0_USE_FPU=2
-CONFIG_HZ_100=y
-CONFIG_CMDLINE_BOOL=y
-CONFIG_CMDLINE_FORCE=y
-CONFIG_PCI_XILINX=y
-CONFIG_MODULES=y
-CONFIG_MODULE_UNLOAD=y
-# CONFIG_BLK_DEV_BSG is not set
-CONFIG_PARTITION_ADVANCED=y
-# CONFIG_EFI_PARTITION is not set
-CONFIG_NET=y
-CONFIG_PACKET=y
-CONFIG_UNIX=y
-CONFIG_INET=y
-# CONFIG_IPV6 is not set
-CONFIG_PCI=y
-CONFIG_MTD=y
-CONFIG_MTD_CMDLINE_PARTS=y
-CONFIG_MTD_BLOCK=y
-CONFIG_MTD_CFI=y
-CONFIG_MTD_CFI_INTELEXT=y
-CONFIG_MTD_CFI_AMDSTD=y
-CONFIG_MTD_RAM=y
-CONFIG_MTD_UCLINUX=y
-CONFIG_BLK_DEV_RAM=y
-CONFIG_BLK_DEV_RAM_SIZE=8192
-CONFIG_NETDEVICES=y
-CONFIG_XILINX_EMACLITE=y
-CONFIG_XILINX_LL_TEMAC=y
-# CONFIG_INPUT is not set
-# CONFIG_SERIO is not set
-# CONFIG_VT is not set
-CONFIG_SERIAL_8250=y
-CONFIG_SERIAL_8250_CONSOLE=y
-CONFIG_SERIAL_OF_PLATFORM=y
-CONFIG_SERIAL_UARTLITE=y
-CONFIG_SERIAL_UARTLITE_CONSOLE=y
-# CONFIG_HW_RANDOM is not set
-CONFIG_XILINX_HWICAP=y
-CONFIG_I2C=y
-CONFIG_I2C_XILINX=y
-CONFIG_SPI=y
-CONFIG_SPI_XILINX=y
-CONFIG_GPIOLIB=y
-CONFIG_GPIO_SYSFS=y
-CONFIG_GPIO_XILINX=y
-CONFIG_POWER_RESET=y
-CONFIG_POWER_RESET_GPIO_RESTART=y
-# CONFIG_HWMON is not set
-CONFIG_WATCHDOG=y
-CONFIG_XILINX_WATCHDOG=y
-CONFIG_FB=y
-CONFIG_FB_XILINX=y
-# CONFIG_USB_SUPPORT is not set
-CONFIG_EXT3_FS=y
-# CONFIG_DNOTIFY is not set
-CONFIG_CRAMFS=y
-CONFIG_ROMFS_FS=y
-CONFIG_NFS_FS=y
-CONFIG_NFS_V3_ACL=y
-CONFIG_NLS=y
-CONFIG_KEYS=y
-CONFIG_ENCRYPTED_KEYS=y
-CONFIG_CRYPTO_ECB=y
-CONFIG_CRYPTO_MD4=y
-CONFIG_CRYPTO_MD5=y
-CONFIG_CRYPTO_ARC4=y
-CONFIG_CRYPTO_DES=y
-CONFIG_DEBUG_INFO=y
-CONFIG_DEBUG_SLAB=y
-CONFIG_DETECT_HUNG_TASK=y
-CONFIG_DEBUG_SPINLOCK=y
diff --git a/arch/microblaze/include/asm/dma.h b/arch/microblaze/include/asm/dma.h
index e6cb6d0725af..f801582be912 100644
--- a/arch/microblaze/include/asm/dma.h
+++ b/arch/microblaze/include/asm/dma.h
@@ -6,14 +6,8 @@
 #ifndef _ASM_MICROBLAZE_DMA_H
 #define _ASM_MICROBLAZE_DMA_H
 
-#ifndef CONFIG_MMU
-/* we don't have dma address limit. define it as zero to be
- * unlimited. */
-#define MAX_DMA_ADDRESS		(0)
-#else
 /* Virtual address corresponding to last available physical memory address.  */
 #define MAX_DMA_ADDRESS (CONFIG_KERNEL_START + memory_size - 1)
-#endif
 
 #ifdef CONFIG_PCI
 extern int isa_dma_bridge_buggy;
diff --git a/arch/microblaze/include/asm/exceptions.h b/arch/microblaze/include/asm/exceptions.h
index d67e65b72215..967f175173e1 100644
--- a/arch/microblaze/include/asm/exceptions.h
+++ b/arch/microblaze/include/asm/exceptions.h
@@ -11,11 +11,6 @@
 #define _ASM_MICROBLAZE_EXCEPTIONS_H
 
 #ifdef __KERNEL__
-
-#ifndef CONFIG_MMU
-#define EX_HANDLER_STACK_SIZ	(4*19)
-#endif
-
 #ifndef __ASSEMBLY__
 
 /* Macros to enable and disable HW exceptions in the MSR */
diff --git a/arch/microblaze/include/asm/io.h b/arch/microblaze/include/asm/io.h
index 1dd6fae41897..b6a57f8468f0 100644
--- a/arch/microblaze/include/asm/io.h
+++ b/arch/microblaze/include/asm/io.h
@@ -30,15 +30,12 @@ extern resource_size_t isa_mem_base;
 #define PCI_IOBASE	((void __iomem *)_IO_BASE)
 #define IO_SPACE_LIMIT (0xFFFFFFFF)
 
-#ifdef CONFIG_MMU
 #define page_to_bus(page)	(page_to_phys(page))
 
 extern void iounmap(volatile void __iomem *addr);
 
 extern void __iomem *ioremap(phys_addr_t address, unsigned long size);
 
-#endif /* CONFIG_MMU */
-
 /* Big Endian */
 #define out_be32(a, v) __raw_writel((v), (void __iomem __force *)(a))
 #define out_be16(a, v) __raw_writew((v), (a))
diff --git a/arch/microblaze/include/asm/mmu.h b/arch/microblaze/include/asm/mmu.h
index 97f1243101cc..b928a87c0076 100644
--- a/arch/microblaze/include/asm/mmu.h
+++ b/arch/microblaze/include/asm/mmu.h
@@ -8,9 +8,6 @@
 #ifndef _ASM_MICROBLAZE_MMU_H
 #define _ASM_MICROBLAZE_MMU_H
 
-# ifndef CONFIG_MMU
-#  include <asm-generic/mmu.h>
-# else /* CONFIG_MMU */
 #  ifdef __KERNEL__
 #   ifndef __ASSEMBLY__
 
@@ -119,5 +116,4 @@ extern u32 tlb_skip;
 #  define TLB_G			0x00000001 /* Memory is guarded from prefetch */
 
 #  endif /* __KERNEL__ */
-# endif /* CONFIG_MMU */
 #endif /* _ASM_MICROBLAZE_MMU_H */
diff --git a/arch/microblaze/include/asm/mmu_context.h b/arch/microblaze/include/asm/mmu_context.h
index f74f9da07fdc..866e52da5eb9 100644
--- a/arch/microblaze/include/asm/mmu_context.h
+++ b/arch/microblaze/include/asm/mmu_context.h
@@ -1,6 +1,2 @@
 /* SPDX-License-Identifier: GPL-2.0 */
-#ifdef CONFIG_MMU
 # include <asm/mmu_context_mm.h>
-#else
-# include <asm-generic/mmu_context.h>
-#endif
diff --git a/arch/microblaze/include/asm/page.h b/arch/microblaze/include/asm/page.h
index b13463d39b38..bf681f272f72 100644
--- a/arch/microblaze/include/asm/page.h
+++ b/arch/microblaze/include/asm/page.h
@@ -20,13 +20,7 @@
 #ifdef __KERNEL__
 
 /* PAGE_SHIFT determines the page size */
-#if defined(CONFIG_MICROBLAZE_64K_PAGES)
-#define PAGE_SHIFT		16
-#elif defined(CONFIG_MICROBLAZE_16K_PAGES)
-#define PAGE_SHIFT		14
-#else
 #define PAGE_SHIFT		12
-#endif
 #define PAGE_SIZE	(ASM_CONST(1) << PAGE_SHIFT)
 #define PAGE_MASK	(~(PAGE_SIZE-1))
 
@@ -44,17 +38,6 @@
 #define PAGE_UP(addr)	(((addr)+((PAGE_SIZE)-1))&(~((PAGE_SIZE)-1)))
 #define PAGE_DOWN(addr)	((addr)&(~((PAGE_SIZE)-1)))
 
-#ifndef CONFIG_MMU
-/*
- * PAGE_OFFSET -- the first address of the first page of memory. When not
- * using MMU this corresponds to the first free page in physical memory (aligned
- * on a page boundary).
- */
-extern unsigned int __page_offset;
-#define PAGE_OFFSET __page_offset
-
-#else /* CONFIG_MMU */
-
 /*
  * PAGE_OFFSET -- the first address of the first page of memory. With MMU
  * it is set to the kernel start address (aligned on a page boundary).
@@ -70,8 +53,6 @@ extern unsigned int __page_offset;
 typedef unsigned long pte_basic_t;
 #define PTE_FMT		"%.8lx"
 
-#endif /* CONFIG_MMU */
-
 # define copy_page(to, from)			memcpy((to), (from), PAGE_SIZE)
 # define clear_page(pgaddr)			memset((pgaddr), 0, PAGE_SIZE)
 
@@ -86,25 +67,12 @@ typedef struct page *pgtable_t;
 typedef struct { unsigned long	pte; }		pte_t;
 typedef struct { unsigned long	pgprot; }	pgprot_t;
 /* FIXME this can depend on linux kernel version */
-#   ifdef CONFIG_MMU
 typedef struct { unsigned long pgd; } pgd_t;
-#   else /* CONFIG_MMU */
-typedef struct { unsigned long	ste[64]; }	pmd_t;
-typedef struct { pmd_t		pue[1]; }	pud_t;
-typedef struct { pud_t		p4e[1]; }	p4d_t;
-typedef struct { p4d_t		pge[1]; }	pgd_t;
-#   endif /* CONFIG_MMU */
 
 # define pte_val(x)	((x).pte)
 # define pgprot_val(x)	((x).pgprot)
 
-#   ifdef CONFIG_MMU
 #   define pgd_val(x)      ((x).pgd)
-#   else  /* CONFIG_MMU */
-#   define pmd_val(x)	((x).ste[0])
-#   define pud_val(x)	((x).pue[0])
-#   define pgd_val(x)	((x).pge[0])
-#   endif  /* CONFIG_MMU */
 
 # define __pte(x)	((pte_t) { (x) })
 # define __pgd(x)	((pgd_t) { (x) })
@@ -142,28 +110,12 @@ extern int page_is_ram(unsigned long pfn);
 # define virt_to_pfn(vaddr)	(phys_to_pfn((__pa(vaddr))))
 # define pfn_to_virt(pfn)	__va(pfn_to_phys((pfn)))
 
-#  ifdef CONFIG_MMU
-
 #  define virt_to_page(kaddr)	(pfn_to_page(__pa(kaddr) >> PAGE_SHIFT))
 #  define page_to_virt(page)   __va(page_to_pfn(page) << PAGE_SHIFT)
 #  define page_to_phys(page)     (page_to_pfn(page) << PAGE_SHIFT)
 
-#  else /* CONFIG_MMU */
-#  define virt_to_page(vaddr)	(pfn_to_page(virt_to_pfn(vaddr)))
-#  define page_to_virt(page)	(pfn_to_virt(page_to_pfn(page)))
-#  define page_to_phys(page)	(pfn_to_phys(page_to_pfn(page)))
-#  define page_to_bus(page)	(page_to_phys(page))
-#  define phys_to_page(paddr)	(pfn_to_page(phys_to_pfn(paddr)))
-#  endif /* CONFIG_MMU */
-
-#  ifndef CONFIG_MMU
-#  define pfn_valid(pfn)	(((pfn) >= min_low_pfn) && \
-				((pfn) <= (min_low_pfn + max_mapnr)))
-#  define ARCH_PFN_OFFSET	(PAGE_OFFSET >> PAGE_SHIFT)
-#  else /* CONFIG_MMU */
 #  define ARCH_PFN_OFFSET	(memory_start >> PAGE_SHIFT)
 #  define pfn_valid(pfn)	((pfn) < (max_mapnr + ARCH_PFN_OFFSET))
-#  endif /* CONFIG_MMU */
 
 # endif /* __ASSEMBLY__ */
 
@@ -174,12 +126,6 @@ extern int page_is_ram(unsigned long pfn);
 
 /* Convert between virtual and physical address for MMU. */
 /* Handle MicroBlaze processor with virtual memory. */
-#ifndef CONFIG_MMU
-#define __virt_to_phys(addr)	addr
-#define __phys_to_virt(addr)	addr
-#define tophys(rd, rs)	addik rd, rs, 0
-#define tovirt(rd, rs)	addik rd, rs, 0
-#else
 #define __virt_to_phys(addr) \
 	((addr) + CONFIG_KERNEL_BASE_ADDR - CONFIG_KERNEL_START)
 #define __phys_to_virt(addr) \
@@ -188,14 +134,9 @@ extern int page_is_ram(unsigned long pfn);
 	addik rd, rs, (CONFIG_KERNEL_BASE_ADDR - CONFIG_KERNEL_START)
 #define tovirt(rd, rs) \
 	addik rd, rs, (CONFIG_KERNEL_START - CONFIG_KERNEL_BASE_ADDR)
-#endif /* CONFIG_MMU */
 
 #define TOPHYS(addr)  __virt_to_phys(addr)
 
-#ifdef CONFIG_MMU
-
-#endif /* CONFIG_MMU */
-
 #endif /* __KERNEL__ */
 
 #include <asm-generic/memory_model.h>
diff --git a/arch/microblaze/include/asm/pgalloc.h b/arch/microblaze/include/asm/pgalloc.h
index 8839ce00ea05..d56b9f670ad1 100644
--- a/arch/microblaze/include/asm/pgalloc.h
+++ b/arch/microblaze/include/asm/pgalloc.h
@@ -8,8 +8,6 @@
 #ifndef _ASM_MICROBLAZE_PGALLOC_H
 #define _ASM_MICROBLAZE_PGALLOC_H
 
-#ifdef CONFIG_MMU
-
 #include <linux/kernel.h>	/* For min/max macros */
 #include <linux/highmem.h>
 #include <linux/pgtable.h>
@@ -42,6 +40,4 @@ extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm);
 #define pmd_populate_kernel(mm, pmd, pte) \
 		(pmd_val(*(pmd)) = (unsigned long) (pte))
 
-#endif /* CONFIG_MMU */
-
 #endif /* _ASM_MICROBLAZE_PGALLOC_H */
diff --git a/arch/microblaze/include/asm/pgtable.h b/arch/microblaze/include/asm/pgtable.h
index 3fa1df90925e..9ae8d2c17dd5 100644
--- a/arch/microblaze/include/asm/pgtable.h
+++ b/arch/microblaze/include/asm/pgtable.h
@@ -14,47 +14,6 @@
 extern int mem_init_done;
 #endif
 
-#ifndef CONFIG_MMU
-
-#define pgd_present(pgd)	(1) /* pages are always present on non MMU */
-#define pgd_none(pgd)		(0)
-#define pgd_bad(pgd)		(0)
-#define pgd_clear(pgdp)
-#define kern_addr_valid(addr)	(1)
-
-#define PAGE_NONE		__pgprot(0) /* these mean nothing to non MMU */
-#define PAGE_SHARED		__pgprot(0) /* these mean nothing to non MMU */
-#define PAGE_COPY		__pgprot(0) /* these mean nothing to non MMU */
-#define PAGE_READONLY		__pgprot(0) /* these mean nothing to non MMU */
-#define PAGE_KERNEL		__pgprot(0) /* these mean nothing to non MMU */
-
-#define pgprot_noncached(x)	(x)
-#define pgprot_writecombine	pgprot_noncached
-#define pgprot_device		pgprot_noncached
-
-#define __swp_type(x)		(0)
-#define __swp_offset(x)		(0)
-#define __swp_entry(typ, off)	((swp_entry_t) { ((typ) | ((off) << 7)) })
-#define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
-#define __swp_entry_to_pte(x)	((pte_t) { (x).val })
-
-#define ZERO_PAGE(vaddr)	({ BUG(); NULL; })
-
-#define swapper_pg_dir ((pgd_t *) NULL)
-
-#define arch_enter_lazy_cpu_mode()	do {} while (0)
-
-#define pgprot_noncached_wc(prot)	prot
-
-/*
- * All 32bit addresses are effectively valid for vmalloc...
- * Sort of meaningless for non-VM targets.
- */
-#define	VMALLOC_START	0
-#define	VMALLOC_END	0xffffffff
-
-#else /* CONFIG_MMU */
-
 #include <asm-generic/pgtable-nopmd.h>
 
 #ifdef __KERNEL__
@@ -491,8 +450,6 @@ void __init *early_get_page(void);
 #endif /* __ASSEMBLY__ */
 #endif /* __KERNEL__ */
 
-#endif /* CONFIG_MMU */
-
 #ifndef __ASSEMBLY__
 extern unsigned long ioremap_bot, ioremap_base;
 
diff --git a/arch/microblaze/include/asm/processor.h b/arch/microblaze/include/asm/processor.h
index 1ff5a82b76b6..f4f3048cde4c 100644
--- a/arch/microblaze/include/asm/processor.h
+++ b/arch/microblaze/include/asm/processor.h
@@ -31,42 +31,6 @@ extern void ret_from_kernel_thread(void);
 
 # endif /* __ASSEMBLY__ */
 
-# ifndef CONFIG_MMU
-/*
- * User space process size: memory size
- *
- * TASK_SIZE on MMU cpu is usually 1GB. However, on no-MMU arch, both
- * user processes and the kernel is on the same memory region. They
- * both share the memory space and that is limited by the amount of
- * physical memory. thus, we set TASK_SIZE == amount of total memory.
- */
-# define TASK_SIZE	(0x81000000 - 0x80000000)
-
-/*
- * This decides where the kernel will search for a free chunk of vm
- * space during mmap's. We won't be using it
- */
-# define TASK_UNMAPPED_BASE	0
-
-/* definition in include/linux/sched.h */
-struct task_struct;
-
-/* thread_struct is gone. use thread_info instead. */
-struct thread_struct { };
-# define INIT_THREAD	{ }
-
-/* Free all resources held by a thread. */
-static inline void release_thread(struct task_struct *dead_task)
-{
-}
-
-extern unsigned long get_wchan(struct task_struct *p);
-
-# define KSTK_EIP(tsk)	(0)
-# define KSTK_ESP(tsk)	(0)
-
-# else /* CONFIG_MMU */
-
 /*
  * This is used to define STACK_TOP, and with MMU it must be below
  * kernel base to select the correct PGD when handling MMU exceptions.
@@ -133,5 +97,4 @@ extern struct dentry *of_debugfs_root;
 #endif
 
 #  endif /* __ASSEMBLY__ */
-# endif /* CONFIG_MMU */
 #endif /* _ASM_MICROBLAZE_PROCESSOR_H */
diff --git a/arch/microblaze/include/asm/registers.h b/arch/microblaze/include/asm/registers.h
index ee81e1cba008..6b36693fc621 100644
--- a/arch/microblaze/include/asm/registers.h
+++ b/arch/microblaze/include/asm/registers.h
@@ -27,7 +27,6 @@
 #define FSR_UF		(1<<1) /* Underflow */
 #define FSR_DO		(1<<0) /* Denormalized operand error */
 
-# ifdef CONFIG_MMU
 /* Machine State Register (MSR) Fields */
 # define MSR_UM		(1<<11) /* User Mode */
 # define MSR_UMS	(1<<12) /* User Mode Save */
@@ -43,5 +42,4 @@
 # define	  ESR_DIZ	(1<<11) /* Zone Protection */
 # define	  ESR_S		(1<<10) /* Store instruction */
 
-# endif /* CONFIG_MMU */
 #endif /* _ASM_MICROBLAZE_REGISTERS_H */
diff --git a/arch/microblaze/include/asm/setup.h b/arch/microblaze/include/asm/setup.h
index be10da9d87cb..a06cc1f97aa9 100644
--- a/arch/microblaze/include/asm/setup.h
+++ b/arch/microblaze/include/asm/setup.h
@@ -14,9 +14,7 @@ extern char cmd_line[COMMAND_LINE_SIZE];
 
 extern char *klimit;
 
-#   ifdef CONFIG_MMU
 extern void mmu_reset(void);
-#   endif /* CONFIG_MMU */
 
 void time_init(void);
 void init_IRQ(void);
diff --git a/arch/microblaze/include/asm/tlbflush.h b/arch/microblaze/include/asm/tlbflush.h
index 1200e2bf14bb..2038168ed128 100644
--- a/arch/microblaze/include/asm/tlbflush.h
+++ b/arch/microblaze/include/asm/tlbflush.h
@@ -8,8 +8,6 @@
 #ifndef _ASM_MICROBLAZE_TLBFLUSH_H
 #define _ASM_MICROBLAZE_TLBFLUSH_H
 
-#ifdef CONFIG_MMU
-
 #include <linux/sched.h>
 #include <linux/threads.h>
 #include <asm/processor.h>	/* For TASK_SIZE */
@@ -50,16 +48,4 @@ static inline void local_flush_tlb_range(struct vm_area_struct *vma,
 static inline void flush_tlb_pgtables(struct mm_struct *mm,
 	unsigned long start, unsigned long end) { }
 
-#else /* CONFIG_MMU */
-
-#define flush_tlb()				BUG()
-#define flush_tlb_all()				BUG()
-#define flush_tlb_mm(mm)			BUG()
-#define flush_tlb_page(vma, addr)		BUG()
-#define flush_tlb_range(mm, start, end)		BUG()
-#define flush_tlb_pgtables(mm, start, end)	BUG()
-#define flush_tlb_kernel_range(start, end)	BUG()
-
-#endif /* CONFIG_MMU */
-
 #endif /* _ASM_MICROBLAZE_TLBFLUSH_H */
diff --git a/arch/microblaze/include/asm/uaccess.h b/arch/microblaze/include/asm/uaccess.h
index 304b04ffea2f..c44b59470e45 100644
--- a/arch/microblaze/include/asm/uaccess.h
+++ b/arch/microblaze/include/asm/uaccess.h
@@ -30,35 +30,14 @@
  */
 # define MAKE_MM_SEG(s)       ((mm_segment_t) { (s) })
 
-#  ifndef CONFIG_MMU
-#  define KERNEL_DS	MAKE_MM_SEG(0)
-#  define USER_DS	KERNEL_DS
-#  else
 #  define KERNEL_DS	MAKE_MM_SEG(0xFFFFFFFF)
 #  define USER_DS	MAKE_MM_SEG(TASK_SIZE - 1)
-#  endif
 
 # define get_fs()	(current_thread_info()->addr_limit)
 # define set_fs(val)	(current_thread_info()->addr_limit = (val))
 
 # define uaccess_kernel()	(get_fs().seg == KERNEL_DS.seg)
 
-#ifndef CONFIG_MMU
-
-/* Check against bounds of physical memory */
-static inline int ___range_ok(unsigned long addr, unsigned long size)
-{
-	return ((addr < memory_start) ||
-		((addr + size - 1) > (memory_start + memory_size - 1)));
-}
-
-#define __range_ok(addr, size) \
-		___range_ok((unsigned long)(addr), (unsigned long)(size))
-
-#define access_ok(addr, size) (__range_ok((addr), (size)) == 0)
-
-#else
-
 static inline int access_ok(const void __user *addr, unsigned long size)
 {
 	if (!size)
@@ -77,15 +56,9 @@ static inline int access_ok(const void __user *addr, unsigned long size)
 			(u32)get_fs().seg);
 	return 1;
 }
-#endif
 
-#ifdef CONFIG_MMU
 # define __FIXUP_SECTION	".section .fixup,\"ax\"\n"
 # define __EX_TABLE_SECTION	".section __ex_table,\"a\"\n"
-#else
-# define __FIXUP_SECTION	".section .discard,\"ax\"\n"
-# define __EX_TABLE_SECTION	".section .discard,\"ax\"\n"
-#endif
 
 extern unsigned long __copy_tofrom_user(void __user *to,
 		const void __user *from, unsigned long size);
diff --git a/arch/microblaze/kernel/Makefile b/arch/microblaze/kernel/Makefile
index dd71637437f4..15a20eb814ce 100644
--- a/arch/microblaze/kernel/Makefile
+++ b/arch/microblaze/kernel/Makefile
@@ -22,9 +22,9 @@ obj-y += dma.o exceptions.o \
 obj-y += cpu/
 
 obj-$(CONFIG_MODULES)		+= microblaze_ksyms.o module.o
-obj-$(CONFIG_MMU)		+= misc.o
+obj-y				+= misc.o
 obj-$(CONFIG_STACKTRACE)	+= stacktrace.o
 obj-$(CONFIG_FUNCTION_TRACER)	+= ftrace.o mcount.o
 obj-$(CONFIG_KGDB)		+= kgdb.o
 
-obj-y	+= entry$(MMU).o
+obj-y	+= entry.o
diff --git a/arch/microblaze/kernel/asm-offsets.c b/arch/microblaze/kernel/asm-offsets.c
index c1b459c97571..6c69ce7be2e8 100644
--- a/arch/microblaze/kernel/asm-offsets.c
+++ b/arch/microblaze/kernel/asm-offsets.c
@@ -70,7 +70,6 @@ int main(int argc, char *argv[])
 
 	/* struct task_struct */
 	DEFINE(TS_THREAD_INFO, offsetof(struct task_struct, stack));
-#ifdef CONFIG_MMU
 	DEFINE(TASK_STATE, offsetof(struct task_struct, state));
 	DEFINE(TASK_FLAGS, offsetof(struct task_struct, flags));
 	DEFINE(TASK_PTRACE, offsetof(struct task_struct, ptrace));
@@ -84,7 +83,6 @@ int main(int argc, char *argv[])
 
 	DEFINE(PGDIR, offsetof(struct thread_struct, pgdir));
 	BLANK();
-#endif
 
 	/* struct thread_info */
 	DEFINE(TI_TASK, offsetof(struct thread_info, task));
diff --git a/arch/microblaze/kernel/entry-nommu.S b/arch/microblaze/kernel/entry-nommu.S
deleted file mode 100644
index 7e394fc2c439..000000000000
--- a/arch/microblaze/kernel/entry-nommu.S
+++ /dev/null
@@ -1,622 +0,0 @@
-/*
- * Copyright (C) 2007-2009 Michal Simek <monstr@monstr.eu>
- * Copyright (C) 2007-2009 PetaLogix
- * Copyright (C) 2006 Atmark Techno, Inc.
- *
- * This file is subject to the terms and conditions of the GNU General Public
- * License. See the file "COPYING" in the main directory of this archive
- * for more details.
- */
-
-#include <linux/linkage.h>
-#include <asm/thread_info.h>
-#include <linux/errno.h>
-#include <asm/entry.h>
-#include <asm/asm-offsets.h>
-#include <asm/registers.h>
-#include <asm/unistd.h>
-#include <asm/percpu.h>
-#include <asm/signal.h>
-
-#if CONFIG_XILINX_MICROBLAZE0_USE_MSR_INSTR
-	.macro	disable_irq
-	msrclr r0, MSR_IE
-	.endm
-
-	.macro	enable_irq
-	msrset r0, MSR_IE
-	.endm
-
-	.macro	clear_bip
-	msrclr r0, MSR_BIP
-	.endm
-#else
-	.macro	disable_irq
-	mfs r11, rmsr
-	andi r11, r11, ~MSR_IE
-	mts rmsr, r11
-	.endm
-
-	.macro	enable_irq
-	mfs r11, rmsr
-	ori r11, r11, MSR_IE
-	mts rmsr, r11
-	.endm
-
-	.macro	clear_bip
-	mfs r11, rmsr
-	andi r11, r11, ~MSR_BIP
-	mts rmsr, r11
-	.endm
-#endif
-
-ENTRY(_interrupt)
-	swi	r1, r0, PER_CPU(ENTRY_SP)	/* save the current sp */
-	swi	r11, r0, PER_CPU(R11_SAVE)	/* temporarily save r11 */
-	lwi	r11, r0, PER_CPU(KM)		/* load mode indicator */
-	beqid	r11, 1f
-	nop
-	brid	2f				/* jump over */
-	addik	r1, r1, (-PT_SIZE)	/* room for pt_regs (delay slot) */
-1:						/* switch to kernel stack */
-	lwi	r1, r0, PER_CPU(CURRENT_SAVE)	/* get the saved current */
-	lwi	r1, r1, TS_THREAD_INFO		/* get the thread info */
-	/* calculate kernel stack pointer */
-	addik	r1, r1, THREAD_SIZE - PT_SIZE
-2:
-	swi	r11, r1, PT_MODE		/* store the mode */
-	lwi	r11, r0, PER_CPU(R11_SAVE)	/* reload r11 */
-	swi	r2, r1, PT_R2
-	swi	r3, r1, PT_R3
-	swi	r4, r1, PT_R4
-	swi	r5, r1, PT_R5
-	swi	r6, r1, PT_R6
-	swi	r7, r1, PT_R7
-	swi	r8, r1, PT_R8
-	swi	r9, r1, PT_R9
-	swi	r10, r1, PT_R10
-	swi	r11, r1, PT_R11
-	swi	r12, r1, PT_R12
-	swi	r13, r1, PT_R13
-	swi	r14, r1, PT_R14
-	swi	r14, r1, PT_PC
-	swi	r15, r1, PT_R15
-	swi	r16, r1, PT_R16
-	swi	r17, r1, PT_R17
-	swi	r18, r1, PT_R18
-	swi	r19, r1, PT_R19
-	swi	r20, r1, PT_R20
-	swi	r21, r1, PT_R21
-	swi	r22, r1, PT_R22
-	swi	r23, r1, PT_R23
-	swi	r24, r1, PT_R24
-	swi	r25, r1, PT_R25
-	swi	r26, r1, PT_R26
-	swi	r27, r1, PT_R27
-	swi	r28, r1, PT_R28
-	swi	r29, r1, PT_R29
-	swi	r30, r1, PT_R30
-	swi	r31, r1, PT_R31
-	/* special purpose registers */
-	mfs	r11, rmsr
-	swi	r11, r1, PT_MSR
-	mfs	r11, rear
-	swi	r11, r1, PT_EAR
-	mfs	r11, resr
-	swi	r11, r1, PT_ESR
-	mfs	r11, rfsr
-	swi	r11, r1, PT_FSR
-	/* reload original stack pointer and save it */
-	lwi	r11, r0, PER_CPU(ENTRY_SP)
-	swi	r11, r1, PT_R1
-	/* update mode indicator we are in kernel mode */
-	addik	r11, r0, 1
-	swi	r11, r0, PER_CPU(KM)
-	/* restore r31 */
-	lwi	r31, r0, PER_CPU(CURRENT_SAVE)
-	/* prepare the link register, the argument and jump */
-	addik	r15, r0, ret_from_intr - 8
-	addk	r6, r0, r15
-	braid	do_IRQ
-	add	r5, r0, r1
-
-ret_from_intr:
-	lwi	r11, r1, PT_MODE
-	bneid	r11, no_intr_resched
-
-3:
-	lwi	r6, r31, TS_THREAD_INFO	/* get thread info */
-	lwi	r19, r6, TI_FLAGS	/* get flags in thread info */
-				/* do an extra work if any bits are set */
-
-	andi	r11, r19, _TIF_NEED_RESCHED
-	beqi	r11, 1f
-	bralid	r15, schedule
-	nop
-	bri	3b
-1:	andi	r11, r19, _TIF_SIGPENDING | _TIF_NOTIFY_RESUME
-	beqid	r11, no_intr_resched
-	addk	r5, r1, r0
-	bralid	r15, do_notify_resume
-	addk	r6, r0, r0
-	bri	3b
-
-no_intr_resched:
-	/* Disable interrupts, we are now committed to the state restore */
-	disable_irq
-
-	/* save mode indicator */
-	lwi	r11, r1, PT_MODE
-	swi	r11, r0, PER_CPU(KM)
-
-	/* save r31 */
-	swi	r31, r0, PER_CPU(CURRENT_SAVE)
-restore_context:
-	/* special purpose registers */
-	lwi	r11, r1, PT_FSR
-	mts	rfsr, r11
-	lwi	r11, r1, PT_ESR
-	mts	resr, r11
-	lwi	r11, r1, PT_EAR
-	mts	rear, r11
-	lwi	r11, r1, PT_MSR
-	mts	rmsr, r11
-
-	lwi	r31, r1, PT_R31
-	lwi	r30, r1, PT_R30
-	lwi	r29, r1, PT_R29
-	lwi	r28, r1, PT_R28
-	lwi	r27, r1, PT_R27
-	lwi	r26, r1, PT_R26
-	lwi	r25, r1, PT_R25
-	lwi	r24, r1, PT_R24
-	lwi	r23, r1, PT_R23
-	lwi	r22, r1, PT_R22
-	lwi	r21, r1, PT_R21
-	lwi	r20, r1, PT_R20
-	lwi	r19, r1, PT_R19
-	lwi	r18, r1, PT_R18
-	lwi	r17, r1, PT_R17
-	lwi	r16, r1, PT_R16
-	lwi	r15, r1, PT_R15
-	lwi	r14, r1, PT_PC
-	lwi	r13, r1, PT_R13
-	lwi	r12, r1, PT_R12
-	lwi	r11, r1, PT_R11
-	lwi	r10, r1, PT_R10
-	lwi	r9, r1, PT_R9
-	lwi	r8, r1, PT_R8
-	lwi	r7, r1, PT_R7
-	lwi	r6, r1, PT_R6
-	lwi	r5, r1, PT_R5
-	lwi	r4, r1, PT_R4
-	lwi	r3, r1, PT_R3
-	lwi	r2, r1, PT_R2
-	lwi	r1, r1, PT_R1
-	rtid	r14, 0
-	nop
-
-ENTRY(_reset)
-	brai	0;
-
-ENTRY(_user_exception)
-	swi	r1, r0, PER_CPU(ENTRY_SP)	/* save the current sp */
-	swi	r11, r0, PER_CPU(R11_SAVE)	/* temporarily save r11 */
-	lwi	r11, r0, PER_CPU(KM)		/* load mode indicator */
-	beqid	r11, 1f				/* Already in kernel mode? */
-	nop
-	brid	2f				/* jump over */
-	addik	r1, r1, (-PT_SIZE)	/* Room for pt_regs (delay slot) */
-1:						/* Switch to kernel stack */
-	lwi	r1, r0, PER_CPU(CURRENT_SAVE)	/* get the saved current */
-	lwi	r1, r1, TS_THREAD_INFO		/* get the thread info */
-	/* calculate kernel stack pointer */
-	addik	r1, r1, THREAD_SIZE - PT_SIZE
-2:
-	swi	r11, r1, PT_MODE		/* store the mode */
-	lwi	r11, r0, PER_CPU(R11_SAVE)	/* reload r11 */
-	/* save them on stack */
-	swi	r2, r1, PT_R2
-	swi	r3, r1, PT_R3 /* r3: _always_ in clobber list; see unistd.h */
-	swi	r4, r1, PT_R4 /* r4: _always_ in clobber list; see unistd.h */
-	swi	r5, r1, PT_R5
-	swi	r6, r1, PT_R6
-	swi	r7, r1, PT_R7
-	swi	r8, r1, PT_R8
-	swi	r9, r1, PT_R9
-	swi	r10, r1, PT_R10
-	swi	r11, r1, PT_R11
-	/* r12: _always_ in clobber list; see unistd.h */
-	swi	r12, r1, PT_R12
-	swi	r13, r1, PT_R13
-	/* r14: _always_ in clobber list; see unistd.h */
-	swi	r14, r1, PT_R14
-	/* but we want to return to the next inst. */
-	addik	r14, r14, 0x4
-	swi	r14, r1, PT_PC		/* increment by 4 and store in pc */
-	swi	r15, r1, PT_R15
-	swi	r16, r1, PT_R16
-	swi	r17, r1, PT_R17
-	swi	r18, r1, PT_R18
-	swi	r19, r1, PT_R19
-	swi	r20, r1, PT_R20
-	swi	r21, r1, PT_R21
-	swi	r22, r1, PT_R22
-	swi	r23, r1, PT_R23
-	swi	r24, r1, PT_R24
-	swi	r25, r1, PT_R25
-	swi	r26, r1, PT_R26
-	swi	r27, r1, PT_R27
-	swi	r28, r1, PT_R28
-	swi	r29, r1, PT_R29
-	swi	r30, r1, PT_R30
-	swi	r31, r1, PT_R31
-
-	disable_irq
-	nop		/* make sure IE bit is in effect */
-	clear_bip	/* once IE is in effect it is safe to clear BIP */
-	nop
-
-	/* special purpose registers */
-	mfs	r11, rmsr
-	swi	r11, r1, PT_MSR
-	mfs	r11, rear
-	swi	r11, r1, PT_EAR
-	mfs	r11, resr
-	swi	r11, r1, PT_ESR
-	mfs	r11, rfsr
-	swi	r11, r1, PT_FSR
-	/* reload original stack pointer and save it */
-	lwi	r11, r0, PER_CPU(ENTRY_SP)
-	swi	r11, r1, PT_R1
-	/* update mode indicator we are in kernel mode */
-	addik	r11, r0, 1
-	swi	r11, r0, PER_CPU(KM)
-	/* restore r31 */
-	lwi	r31, r0, PER_CPU(CURRENT_SAVE)
-	/* re-enable interrupts now we are in kernel mode */
-	enable_irq
-
-	/* See if the system call number is valid. */
-	addi	r11, r12, -__NR_syscalls
-	bgei	r11, 1f			/* return to user if not valid */
-	/* Figure out which function to use for this system call. */
-	/* Note Microblaze barrel shift is optional, so don't rely on it */
-	add	r12, r12, r12			/* convert num -> ptr */
-	addik	r30, r0, 1			/* restarts allowed */
-	add	r12, r12, r12
-	lwi	r12, r12, sys_call_table	/* Get function pointer */
-	addik	r15, r0, ret_to_user-8		/* set return address */
-	bra	r12				/* Make the system call. */
-	bri	0				/* won't reach here */
-1:
-	brid	ret_to_user			/* jump to syscall epilogue */
-	addi	r3, r0, -ENOSYS			/* set errno in delay slot */
-
-/*
- * Debug traps are like a system call, but entered via brki r14, 0x60
- * All we need to do is send the SIGTRAP signal to current, ptrace and
- * do_notify_resume will handle the rest
- */
-ENTRY(_debug_exception)
-	swi	r1, r0, PER_CPU(ENTRY_SP)	/* save the current sp */
-	lwi	r1, r0, PER_CPU(CURRENT_SAVE)	/* get the saved current */
-	lwi	r1, r1, TS_THREAD_INFO		/* get the thread info */
-	addik	r1, r1, THREAD_SIZE - PT_SIZE	/* get the kernel stack */
-	swi	r11, r0, PER_CPU(R11_SAVE)	/* temporarily save r11 */
-	lwi	r11, r0, PER_CPU(KM)		/* load mode indicator */
-//save_context:
-	swi	r11, r1, PT_MODE	/* store the mode */
-	lwi	r11, r0, PER_CPU(R11_SAVE)	/* reload r11 */
-	/* save them on stack */
-	swi	r2, r1, PT_R2
-	swi	r3, r1, PT_R3 /* r3: _always_ in clobber list; see unistd.h */
-	swi	r4, r1, PT_R4 /* r4: _always_ in clobber list; see unistd.h */
-	swi	r5, r1, PT_R5
-	swi	r6, r1, PT_R6
-	swi	r7, r1, PT_R7
-	swi	r8, r1, PT_R8
-	swi	r9, r1, PT_R9
-	swi	r10, r1, PT_R10
-	swi	r11, r1, PT_R11
-	/* r12: _always_ in clobber list; see unistd.h */
-	swi	r12, r1, PT_R12
-	swi	r13, r1, PT_R13
-	/* r14: _always_ in clobber list; see unistd.h */
-	swi	r14, r1, PT_R14
-	swi	r14, r1, PT_PC /* Will return to interrupted instruction */
-	swi	r15, r1, PT_R15
-	swi	r16, r1, PT_R16
-	swi	r17, r1, PT_R17
-	swi	r18, r1, PT_R18
-	swi	r19, r1, PT_R19
-	swi	r20, r1, PT_R20
-	swi	r21, r1, PT_R21
-	swi	r22, r1, PT_R22
-	swi	r23, r1, PT_R23
-	swi	r24, r1, PT_R24
-	swi	r25, r1, PT_R25
-	swi	r26, r1, PT_R26
-	swi	r27, r1, PT_R27
-	swi	r28, r1, PT_R28
-	swi	r29, r1, PT_R29
-	swi	r30, r1, PT_R30
-	swi	r31, r1, PT_R31
-
-	disable_irq
-	nop		/* make sure IE bit is in effect */
-	clear_bip	/* once IE is in effect it is safe to clear BIP */
-	nop
-
-	/* special purpose registers */
-	mfs	r11, rmsr
-	swi	r11, r1, PT_MSR
-	mfs	r11, rear
-	swi	r11, r1, PT_EAR
-	mfs	r11, resr
-	swi	r11, r1, PT_ESR
-	mfs	r11, rfsr
-	swi	r11, r1, PT_FSR
-	/* reload original stack pointer and save it */
-	lwi	r11, r0, PER_CPU(ENTRY_SP)
-	swi	r11, r1, PT_R1
-	/* update mode indicator we are in kernel mode */
-	addik	r11, r0, 1
-	swi	r11, r0, PER_CPU(KM)
-	/* restore r31 */
-	lwi	r31, r0, PER_CPU(CURRENT_SAVE)
-	/* re-enable interrupts now we are in kernel mode */
-	enable_irq
-
-	addi	r5, r0, SIGTRAP			/* sending the trap signal */
-	add	r6, r0, r31			/* to current */
-	bralid	r15, send_sig
-	add	r7, r0, r0			/* 3rd param zero */
-
-	addik	r30, r0, 1			/* restarts allowed ??? */
-	/* Restore r3/r4 to work around how ret_to_user works */
-	lwi	r3, r1, PT_R3
-	lwi	r4, r1, PT_R4
-	bri	ret_to_user
-
-ENTRY(_break)
-	bri	0
-
-/* struct task_struct *_switch_to(struct thread_info *prev,
-					struct thread_info *next); */
-ENTRY(_switch_to)
-	/* prepare return value */
-	addk	r3, r0, r31
-
-	/* save registers in cpu_context */
-	/* use r11 and r12, volatile registers, as temp register */
-	addik	r11, r5, TI_CPU_CONTEXT
-	swi	r1, r11, CC_R1
-	swi	r2, r11, CC_R2
-	/* skip volatile registers.
-	 * they are saved on stack when we jumped to _switch_to() */
-	/* dedicated registers */
-	swi	r13, r11, CC_R13
-	swi	r14, r11, CC_R14
-	swi	r15, r11, CC_R15
-	swi	r16, r11, CC_R16
-	swi	r17, r11, CC_R17
-	swi	r18, r11, CC_R18
-	/* save non-volatile registers */
-	swi	r19, r11, CC_R19
-	swi	r20, r11, CC_R20
-	swi	r21, r11, CC_R21
-	swi	r22, r11, CC_R22
-	swi	r23, r11, CC_R23
-	swi	r24, r11, CC_R24
-	swi	r25, r11, CC_R25
-	swi	r26, r11, CC_R26
-	swi	r27, r11, CC_R27
-	swi	r28, r11, CC_R28
-	swi	r29, r11, CC_R29
-	swi	r30, r11, CC_R30
-	/* special purpose registers */
-	mfs	r12, rmsr
-	swi	r12, r11, CC_MSR
-	mfs	r12, rear
-	swi	r12, r11, CC_EAR
-	mfs	r12, resr
-	swi	r12, r11, CC_ESR
-	mfs	r12, rfsr
-	swi	r12, r11, CC_FSR
-
-	/* update r31, the current */
-	lwi	r31, r6, TI_TASK
-	swi	r31, r0, PER_CPU(CURRENT_SAVE)
-
-	/* get new process' cpu context and restore */
-	addik	r11, r6, TI_CPU_CONTEXT
-
-	/* special purpose registers */
-	lwi	r12, r11, CC_FSR
-	mts	rfsr, r12
-	lwi	r12, r11, CC_ESR
-	mts	resr, r12
-	lwi	r12, r11, CC_EAR
-	mts	rear, r12
-	lwi	r12, r11, CC_MSR
-	mts	rmsr, r12
-	/* non-volatile registers */
-	lwi	r30, r11, CC_R30
-	lwi	r29, r11, CC_R29
-	lwi	r28, r11, CC_R28
-	lwi	r27, r11, CC_R27
-	lwi	r26, r11, CC_R26
-	lwi	r25, r11, CC_R25
-	lwi	r24, r11, CC_R24
-	lwi	r23, r11, CC_R23
-	lwi	r22, r11, CC_R22
-	lwi	r21, r11, CC_R21
-	lwi	r20, r11, CC_R20
-	lwi	r19, r11, CC_R19
-	/* dedicated registers */
-	lwi	r18, r11, CC_R18
-	lwi	r17, r11, CC_R17
-	lwi	r16, r11, CC_R16
-	lwi	r15, r11, CC_R15
-	lwi	r14, r11, CC_R14
-	lwi	r13, r11, CC_R13
-	/* skip volatile registers */
-	lwi	r2, r11, CC_R2
-	lwi	r1, r11, CC_R1
-
-	rtsd	r15, 8
-	nop
-
-ENTRY(ret_from_fork)
-	addk	r5, r0, r3
-	brlid	r15, schedule_tail
-	nop
-	swi	r31, r1, PT_R31		/* save r31 in user context. */
-			/* will soon be restored to r31 in ret_to_user */
-	addk	r3, r0, r0
-	brid	ret_to_user
-	nop
-
-ENTRY(ret_from_kernel_thread)
-	brlid	r15, schedule_tail
-	addk	r5, r0, r3
-	brald	r15, r20
-	addk	r5, r0, r19
-	brid	ret_to_user
-	addk	r3, r0, r0
-
-work_pending:
-	lwi	r11, r1, PT_MODE
-	bneid	r11, 2f
-3:
-	enable_irq
-	andi	r11, r19, _TIF_NEED_RESCHED
-	beqi	r11, 1f
-	bralid	r15, schedule
-	nop
-	bri	4f
-1:	andi	r11, r19, _TIF_SIGPENDING | _TIF_NOTIFY_RESUME
-	beqi	r11, no_work_pending
-	addk	r5, r30, r0
-	bralid	r15, do_notify_resume
-	addik	r6, r0, 1
-	addk	r30, r0, r0	/* no restarts from now on */
-4:
-	disable_irq
-	lwi	r6, r31, TS_THREAD_INFO /* get thread info */
-	lwi	r19, r6, TI_FLAGS /* get flags in thread info */
-	bri	3b
-
-ENTRY(ret_to_user)
-	disable_irq
-
-	swi	r4, r1, PT_R4		/* return val */
-	swi	r3, r1, PT_R3		/* return val */
-
-	lwi	r6, r31, TS_THREAD_INFO /* get thread info */
-	lwi	r19, r6, TI_FLAGS /* get flags in thread info */
-	bnei	r19, work_pending /* do an extra work if any bits are set */
-no_work_pending:
-	disable_irq
-
-2:
-	/* save r31 */
-	swi	r31, r0, PER_CPU(CURRENT_SAVE)
-	/* save mode indicator */
-	lwi	r18, r1, PT_MODE
-	swi	r18, r0, PER_CPU(KM)
-//restore_context:
-	/* special purpose registers */
-	lwi	r18, r1, PT_FSR
-	mts	rfsr, r18
-	lwi	r18, r1, PT_ESR
-	mts	resr, r18
-	lwi	r18, r1, PT_EAR
-	mts	rear, r18
-	lwi	r18, r1, PT_MSR
-	mts	rmsr, r18
-
-	lwi	r31, r1, PT_R31
-	lwi	r30, r1, PT_R30
-	lwi	r29, r1, PT_R29
-	lwi	r28, r1, PT_R28
-	lwi	r27, r1, PT_R27
-	lwi	r26, r1, PT_R26
-	lwi	r25, r1, PT_R25
-	lwi	r24, r1, PT_R24
-	lwi	r23, r1, PT_R23
-	lwi	r22, r1, PT_R22
-	lwi	r21, r1, PT_R21
-	lwi	r20, r1, PT_R20
-	lwi	r19, r1, PT_R19
-	lwi	r18, r1, PT_R18
-	lwi	r17, r1, PT_R17
-	lwi	r16, r1, PT_R16
-	lwi	r15, r1, PT_R15
-	lwi	r14, r1, PT_PC
-	lwi	r13, r1, PT_R13
-	lwi	r12, r1, PT_R12
-	lwi	r11, r1, PT_R11
-	lwi	r10, r1, PT_R10
-	lwi	r9, r1, PT_R9
-	lwi	r8, r1, PT_R8
-	lwi	r7, r1, PT_R7
-	lwi	r6, r1, PT_R6
-	lwi	r5, r1, PT_R5
-	lwi	r4, r1, PT_R4		/* return val */
-	lwi	r3, r1, PT_R3		/* return val */
-	lwi	r2, r1, PT_R2
-	lwi	r1, r1, PT_R1
-
-	rtid	r14, 0
-	nop
-
-sys_rt_sigreturn_wrapper:
-	addk	r30, r0, r0		/* no restarts for this one */
-	brid	sys_rt_sigreturn
-	addk	r5, r1, r0
-
-	/* Interrupt vector table */
-	.section	.init.ivt, "ax"
-	.org 0x0
-	brai	_reset
-	brai	_user_exception
-	brai	_interrupt
-	brai	_break
-	brai	_hw_exception_handler
-	.org 0x60
-	brai	_debug_exception
-
-.section .rodata,"a"
-#include "syscall_table.S"
-
-syscall_table_size=(.-sys_call_table)
-
-type_SYSCALL:
-	.ascii "SYSCALL\0"
-type_IRQ:
-	.ascii "IRQ\0"
-type_IRQ_PREEMPT:
-	.ascii "IRQ (PREEMPTED)\0"
-type_SYSCALL_PREEMPT:
-	.ascii " SYSCALL (PREEMPTED)\0"
-
-	/*
-	 * Trap decoding for stack unwinder
-	 * Tuples are (start addr, end addr, string)
-	 * If return address lies on [start addr, end addr],
-	 * unwinder displays 'string'
-	 */
-
-	.align 4
-.global microblaze_trap_handlers
-microblaze_trap_handlers:
-	/* Exact matches come first */
-	.word ret_to_user  ; .word ret_to_user    ; .word type_SYSCALL
-	.word ret_from_intr; .word ret_from_intr  ; .word type_IRQ
-	/* Fuzzy matches go here */
-	.word ret_from_intr; .word no_intr_resched; .word type_IRQ_PREEMPT
-	.word work_pending ; .word no_work_pending; .word type_SYSCALL_PREEMPT
-	/* End of table */
-	.word 0             ; .word 0               ; .word 0
diff --git a/arch/microblaze/kernel/exceptions.c b/arch/microblaze/kernel/exceptions.c
index cf99c411503e..908788497b28 100644
--- a/arch/microblaze/kernel/exceptions.c
+++ b/arch/microblaze/kernel/exceptions.c
@@ -69,9 +69,7 @@ void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr)
 asmlinkage void full_exception(struct pt_regs *regs, unsigned int type,
 							int fsr, int addr)
 {
-#ifdef CONFIG_MMU
 	addr = regs->pc;
-#endif
 
 #if 0
 	pr_warn("Exception %02x in %s mode, FSR=%08x PC=%08x ESR=%08x\n",
@@ -132,13 +130,10 @@ asmlinkage void full_exception(struct pt_regs *regs, unsigned int type,
 			fsr = FPE_FLTRES;
 		_exception(SIGFPE, regs, fsr, addr);
 		break;
-
-#ifdef CONFIG_MMU
 	case MICROBLAZE_PRIVILEGED_EXCEPTION:
 		pr_debug("Privileged exception\n");
 		_exception(SIGILL, regs, ILL_PRVOPC, addr);
 		break;
-#endif
 	default:
 	/* FIXME what to do in unexpected exception */
 		pr_warn("Unexpected exception %02x PC=%08x in %s mode\n",
diff --git a/arch/microblaze/kernel/head.S b/arch/microblaze/kernel/head.S
index 14b276406153..ec2fcb545e64 100644
--- a/arch/microblaze/kernel/head.S
+++ b/arch/microblaze/kernel/head.S
@@ -34,7 +34,6 @@
 #include <asm/page.h>
 #include <linux/of_fdt.h>		/* for OF_DT_HEADER */
 
-#ifdef CONFIG_MMU
 #include <asm/setup.h> /* COMMAND_LINE_SIZE */
 #include <asm/mmu.h>
 #include <asm/processor.h>
@@ -48,8 +47,6 @@ empty_zero_page:
 swapper_pg_dir:
 	.space	PAGE_SIZE
 
-#endif /* CONFIG_MMU */
-
 .section .rodata
 .align 4
 endian_check:
@@ -108,8 +105,6 @@ _copy_fdt:
 	addik	r3, r3, -4 /* descrement loop */
 no_fdt_arg:
 
-#ifdef CONFIG_MMU
-
 #ifndef CONFIG_CMDLINE_BOOL
 /*
  * handling command line
@@ -329,7 +324,6 @@ turn_on_mmu:
 	nop
 
 start_here:
-#endif /* CONFIG_MMU */
 
 	/* Initialize small data anchors */
 	addik	r13, r0, _KERNEL_SDA_BASE_
@@ -345,11 +339,6 @@ start_here:
 	brald	r15, r11
 	nop
 
-#ifndef CONFIG_MMU
-	addik	r15, r0, machine_halt
-	braid	start_kernel
-	nop
-#else
 	/*
 	 * Initialize the MMU.
 	 */
@@ -383,4 +372,3 @@ kernel_load_context:
 	nop
 	rted	r17, 0		/* enable MMU and jump to start_kernel */
 	nop
-#endif /* CONFIG_MMU */
diff --git a/arch/microblaze/kernel/hw_exception_handler.S b/arch/microblaze/kernel/hw_exception_handler.S
index 54411de22fa6..07ea23965f81 100644
--- a/arch/microblaze/kernel/hw_exception_handler.S
+++ b/arch/microblaze/kernel/hw_exception_handler.S
@@ -80,7 +80,6 @@
 /* Helpful Macros */
 #define NUM_TO_REG(num)		r ## num
 
-#ifdef CONFIG_MMU
 	#define RESTORE_STATE			\
 		lwi	r5, r1, 0;		\
 		mts	rmsr, r5;		\
@@ -92,7 +91,6 @@
 		lwi	r11, r1, PT_R11;	\
 		lwi	r31, r1, PT_R31;	\
 		lwi	r1, r1, PT_R1;
-#endif /* CONFIG_MMU */
 
 #define LWREG_NOP			\
 	bri	ex_handler_unhandled;	\
@@ -102,10 +100,6 @@
 	bri	ex_handler_unhandled;	\
 	nop;
 
-/* FIXME this is weird - for noMMU kernel is not possible to use brid
- * instruction which can shorten executed time
- */
-
 /* r3 is the source */
 #define R3_TO_LWREG_V(regnum)				\
 	swi	r3, r1, 4 * regnum;				\
@@ -126,7 +120,6 @@
 	or	r3, r0, NUM_TO_REG (regnum);		\
 	bri	ex_sw_tail;
 
-#ifdef CONFIG_MMU
 	#define R3_TO_LWREG_VM_V(regnum)		\
 		brid	ex_lw_end_vm;			\
 		swi	r3, r7, 4 * regnum;
@@ -193,7 +186,6 @@
 	.endm
 	#endif
 
-#endif /* CONFIG_MMU */
 
 .extern other_exception_handler /* Defined in exception.c */
 
@@ -251,7 +243,6 @@
  */
 
 /* wrappers to restore state before coming to entry.S */
-#ifdef CONFIG_MMU
 .section .data
 .align 4
 pt_pool_space:
@@ -316,31 +307,24 @@ _MB_HW_ExceptionVectorTable:
 	.long	TOPHYS(ex_handler_unhandled)
 	.long	TOPHYS(ex_handler_unhandled)
 	.long	TOPHYS(ex_handler_unhandled)
-#endif
 
 .global _hw_exception_handler
 .section .text
 .align 4
 .ent _hw_exception_handler
 _hw_exception_handler:
-#ifndef CONFIG_MMU
-	addik	r1, r1, -(EX_HANDLER_STACK_SIZ); /* Create stack frame */
-#else
 	swi	r1, r0, TOPHYS(pt_pool_space + PT_R1); /* GET_SP */
 	/* Save date to kernel memory. Here is the problem
 	 * when you came from user space */
 	ori	r1, r0, TOPHYS(pt_pool_space);
-#endif
 	swi	r3, r1, PT_R3
 	swi	r4, r1, PT_R4
 	swi	r5, r1, PT_R5
 	swi	r6, r1, PT_R6
 
-#ifdef CONFIG_MMU
 	swi	r11, r1, PT_R11
 	swi	r31, r1, PT_R31
 	lwi	r31, r0, TOPHYS(PER_CPU(CURRENT_SAVE)) /* get saved current */
-#endif
 
 	mfs	r5, rmsr;
 	nop
@@ -350,18 +334,8 @@ _hw_exception_handler:
 	mfs	r3, rear;
 	nop
 
-#ifndef CONFIG_MMU
-	andi	r5, r4, 0x1000;		/* Check ESR[DS] */
-	beqi	r5, not_in_delay_slot;	/* Branch if ESR[DS] not set */
-	mfs	r17, rbtr;	/* ESR[DS] set - return address in BTR */
-	nop
-not_in_delay_slot:
-	swi	r17, r1, PT_R17
-#endif
-
 	andi	r5, r4, 0x1F;		/* Extract ESR[EXC] */
 
-#ifdef CONFIG_MMU
 	/* Calculate exception vector offset = r5 << 2 */
 	addk	r6, r5, r5; /* << 1 */
 	addk	r6, r6, r6; /* << 2 */
@@ -383,73 +357,6 @@ not_in_delay_slot:
 full_exception_trapw:
 	RESTORE_STATE
 	bri	full_exception_trap
-#else
-	/* Exceptions enabled here. This will allow nested exceptions */
-	mfs	r6, rmsr;
-	nop
-	swi	r6, r1, 0; /* RMSR_OFFSET */
-	ori	r6, r6, 0x100; /* Turn ON the EE bit */
-	andi	r6, r6, ~2; /* Disable interrupts */
-	mts	rmsr, r6;
-	nop
-
-	xori	r6, r5, 1; /* 00001 = Unaligned Exception */
-	/* Jump to unalignment exception handler */
-	beqi	r6, handle_unaligned_ex;
-
-handle_other_ex: /* Handle Other exceptions here */
-	/* Save other volatiles before we make procedure calls below */
-	swi	r7, r1, PT_R7
-	swi	r8, r1, PT_R8
-	swi	r9, r1, PT_R9
-	swi	r10, r1, PT_R10
-	swi	r11, r1, PT_R11
-	swi	r12, r1, PT_R12
-	swi	r14, r1, PT_R14
-	swi	r15, r1, PT_R15
-	swi	r18, r1, PT_R18
-
-	or	r5, r1, r0
-	andi	r6, r4, 0x1F; /* Load ESR[EC] */
-	lwi	r7, r0, PER_CPU(KM) /* MS: saving current kernel mode to regs */
-	swi	r7, r1, PT_MODE
-	mfs	r7, rfsr
-	nop
-	addk	r8, r17, r0; /* Load exception address */
-	bralid	r15, full_exception; /* Branch to the handler */
-	nop;
-	mts	rfsr, r0;	/* Clear sticky fsr */
-	nop
-
-	/*
-	 * Trigger execution of the signal handler by enabling
-	 * interrupts and calling an invalid syscall.
-	 */
-	mfs	r5, rmsr;
-	nop
-	ori	r5, r5, 2;
-	mts	rmsr, r5; /* enable interrupt */
-	nop
-	addi	r12, r0, __NR_syscalls;
-	brki	r14, 0x08;
-	mfs	r5, rmsr; /* disable interrupt */
-	nop
-	andi	r5, r5, ~2;
-	mts	rmsr, r5;
-	nop
-
-	lwi	r7, r1, PT_R7
-	lwi	r8, r1, PT_R8
-	lwi	r9, r1, PT_R9
-	lwi	r10, r1, PT_R10
-	lwi	r11, r1, PT_R11
-	lwi	r12, r1, PT_R12
-	lwi	r14, r1, PT_R14
-	lwi	r15, r1, PT_R15
-	lwi	r18, r1, PT_R18
-
-	bri	ex_handler_done; /* Complete exception handling */
-#endif
 
 /* 0x01 - Unaligned data access exception
  * This occurs when a word access is not aligned on a word boundary,
@@ -463,7 +370,6 @@ handle_unaligned_ex:
 	 *  R4 = ESR
 	 *  R3 = EAR
 	 */
-#ifdef CONFIG_MMU
 	andi	r6, r4, 0x1000			/* Check ESR[DS] */
 	beqi	r6, _no_delayslot		/* Branch if ESR[DS] not set */
 	mfs	r17, rbtr;	/* ESR[DS] set - return address in BTR */
@@ -472,7 +378,7 @@ _no_delayslot:
 	/* jump to high level unaligned handler */
 	RESTORE_STATE;
 	bri	unaligned_data_trap
-#endif
+
 	andi	r6, r4, 0x3E0; /* Mask and extract the register operand */
 	srl	r6, r6; /* r6 >> 5 */
 	srl	r6, r6;
@@ -558,25 +464,10 @@ ex_shw:
 ex_sw_end: /* Exception handling of store word, ends. */
 
 ex_handler_done:
-#ifndef CONFIG_MMU
-	lwi	r5, r1, 0 /* RMSR */
-	mts	rmsr, r5
-	nop
-	lwi	r3, r1, PT_R3
-	lwi	r4, r1, PT_R4
-	lwi	r5, r1, PT_R5
-	lwi	r6, r1, PT_R6
-	lwi	r17, r1, PT_R17
-
-	rted	r17, 0
-	addik	r1, r1, (EX_HANDLER_STACK_SIZ); /* Restore stack frame */
-#else
 	RESTORE_STATE;
 	rted	r17, 0
 	nop
-#endif
 
-#ifdef CONFIG_MMU
 	/* Exception vector entry code. This code runs with address translation
 	 * turned off (i.e. using physical addresses). */
 
@@ -882,13 +773,7 @@ ex_handler_done:
 		 * bits 20 and 21 are zero.
 		 */
 		andi	r3, r3, PAGE_MASK
-#ifdef CONFIG_MICROBLAZE_64K_PAGES
-		ori	r3, r3, TLB_VALID | TLB_PAGESZ(PAGESZ_64K)
-#elif CONFIG_MICROBLAZE_16K_PAGES
-		ori	r3, r3, TLB_VALID | TLB_PAGESZ(PAGESZ_16K)
-#else
 		ori	r3, r3, TLB_VALID | TLB_PAGESZ(PAGESZ_4K)
-#endif
 		mts	rtlbhi,	r3		/* Load TLB HI */
 		nop
 
@@ -926,10 +811,8 @@ ex_handler_done:
 		rtsd	r15,8
 		nop
 
-#endif
 .end _hw_exception_handler
 
-#ifdef CONFIG_MMU
 /* Unaligned data access exception last on a 4k page for MMU.
  * When this is called, we are in virtual mode with exceptions enabled
  * and registers 1-13,15,17,18 saved.
@@ -1044,7 +927,6 @@ ex_unaligned_fixup:
 	.word	store6,ex_unaligned_fixup;
 .previous;
 .end _unaligned_data_exception
-#endif /* CONFIG_MMU */
 
 .global ex_handler_unhandled
 ex_handler_unhandled:
@@ -1093,11 +975,7 @@ lw_r27:		R3_TO_LWREG	(27);
 lw_r28:		R3_TO_LWREG	(28);
 lw_r29:		R3_TO_LWREG	(29);
 lw_r30:		R3_TO_LWREG	(30);
-#ifdef CONFIG_MMU
 lw_r31: 	R3_TO_LWREG_V	(31);
-#else
-lw_r31:		R3_TO_LWREG	(31);
-#endif
 
 sw_table:
 sw_r0:		SWREG_TO_R3	(0);
@@ -1131,13 +1009,8 @@ sw_r27:		SWREG_TO_R3	(27);
 sw_r28:		SWREG_TO_R3	(28);
 sw_r29:		SWREG_TO_R3	(29);
 sw_r30:		SWREG_TO_R3	(30);
-#ifdef CONFIG_MMU
 sw_r31:		SWREG_TO_R3_V	(31);
-#else
-sw_r31:		SWREG_TO_R3	(31);
-#endif
 
-#ifdef CONFIG_MMU
 lw_table_vm:
 lw_r0_vm:	R3_TO_LWREG_VM		(0);
 lw_r1_vm:	R3_TO_LWREG_VM_V	(1);
@@ -1205,7 +1078,6 @@ sw_r28_vm:	SWREG_TO_R3_VM_V	(28);
 sw_r29_vm:	SWREG_TO_R3_VM_V	(29);
 sw_r30_vm:	SWREG_TO_R3_VM_V	(30);
 sw_r31_vm:	SWREG_TO_R3_VM_V	(31);
-#endif /* CONFIG_MMU */
 
 /* Temporary data structures used in the handler */
 .section .data
diff --git a/arch/microblaze/kernel/microblaze_ksyms.c b/arch/microblaze/kernel/microblaze_ksyms.c
index 51c43ee5e380..303aaf13573b 100644
--- a/arch/microblaze/kernel/microblaze_ksyms.c
+++ b/arch/microblaze/kernel/microblaze_ksyms.c
@@ -33,9 +33,7 @@ EXPORT_SYMBOL(memcpy);
 EXPORT_SYMBOL(memmove);
 #endif
 
-#ifdef CONFIG_MMU
 EXPORT_SYMBOL(empty_zero_page);
-#endif
 
 EXPORT_SYMBOL(mbc);
 
diff --git a/arch/microblaze/kernel/process.c b/arch/microblaze/kernel/process.c
index a9e46e525cd0..3afda1823730 100644
--- a/arch/microblaze/kernel/process.c
+++ b/arch/microblaze/kernel/process.c
@@ -69,9 +69,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 		ti->cpu_context.r19 = (unsigned long)arg;
 		childregs->pt_mode = 1;
 		local_save_flags(childregs->msr);
-#ifdef CONFIG_MMU
 		ti->cpu_context.msr = childregs->msr & ~MSR_IE;
-#endif
 		ti->cpu_context.r15 = (unsigned long)ret_from_kernel_thread - 8;
 		return 0;
 	}
@@ -81,9 +79,6 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 
 	memset(&ti->cpu_context, 0, sizeof(struct cpu_context));
 	ti->cpu_context.r1 = (unsigned long)childregs;
-#ifndef CONFIG_MMU
-	ti->cpu_context.msr = (unsigned long)childregs->msr;
-#else
 	childregs->msr |= MSR_UMS;
 
 	/* we should consider the fact that childregs is a copy of the parent
@@ -105,7 +100,6 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 	ti->cpu_context.msr = (childregs->msr|MSR_VM);
 	ti->cpu_context.msr &= ~MSR_UMS; /* switch_to to kernel mode */
 	ti->cpu_context.msr &= ~MSR_IE;
-#endif
 	ti->cpu_context.r15 = (unsigned long)ret_from_fork - 8;
 
 	/*
@@ -130,13 +124,10 @@ void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long usp)
 	regs->pc = pc;
 	regs->r1 = usp;
 	regs->pt_mode = 0;
-#ifdef CONFIG_MMU
 	regs->msr |= MSR_UMS;
 	regs->msr &= ~MSR_VM;
-#endif
 }
 
-#ifdef CONFIG_MMU
 #include <linux/elfcore.h>
 /*
  * Set up a thread for executing a new program
@@ -145,7 +136,6 @@ int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpregs)
 {
 	return 0; /* MicroBlaze has no separate FPU registers */
 }
-#endif /* CONFIG_MMU */
 
 void arch_cpu_idle(void)
 {
diff --git a/arch/microblaze/kernel/setup.c b/arch/microblaze/kernel/setup.c
index 7fcf5279ad15..f417333eccae 100644
--- a/arch/microblaze/kernel/setup.c
+++ b/arch/microblaze/kernel/setup.c
@@ -190,12 +190,10 @@ static int microblaze_debugfs_init(void)
 }
 arch_initcall(microblaze_debugfs_init);
 
-# ifdef CONFIG_MMU
 static int __init debugfs_tlb(void)
 {
 	debugfs_create_u32("tlb_skip", S_IRUGO, of_debugfs_root, &tlb_skip);
 	return 0;
 }
 device_initcall(debugfs_tlb);
-# endif
 #endif
diff --git a/arch/microblaze/kernel/signal.c b/arch/microblaze/kernel/signal.c
index 5a8d173d7b75..fc61eb0eb8dd 100644
--- a/arch/microblaze/kernel/signal.c
+++ b/arch/microblaze/kernel/signal.c
@@ -157,10 +157,8 @@ static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
 	struct rt_sigframe __user *frame;
 	int err = 0, sig = ksig->sig;
 	unsigned long address = 0;
-#ifdef CONFIG_MMU
 	pmd_t *pmdp;
 	pte_t *ptep;
-#endif
 
 	frame = get_sigframe(ksig, regs, sizeof(*frame));
 
@@ -192,7 +190,6 @@ static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
 	regs->r15 = ((unsigned long)frame->tramp)-8;
 
 	address = ((unsigned long)frame->tramp);
-#ifdef CONFIG_MMU
 	pmdp = pmd_off(current->mm, address);
 
 	preempt_disable();
@@ -208,10 +205,6 @@ static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
 	}
 	pte_unmap(ptep);
 	preempt_enable();
-#else
-	flush_icache_range(address, address + 8);
-	flush_dcache_range(address, address + 8);
-#endif
 	if (err)
 		return -EFAULT;
 
diff --git a/arch/microblaze/kernel/unwind.c b/arch/microblaze/kernel/unwind.c
index 778a761af0a7..a530a7a6be7d 100644
--- a/arch/microblaze/kernel/unwind.c
+++ b/arch/microblaze/kernel/unwind.c
@@ -161,22 +161,12 @@ static void microblaze_unwind_inner(struct task_struct *task,
  * unwind_trap - Unwind through a system trap, that stored previous state
  *		 on the stack.
  */
-#ifdef CONFIG_MMU
 static inline void unwind_trap(struct task_struct *task, unsigned long pc,
 				unsigned long fp, struct stack_trace *trace,
 				const char *loglvl)
 {
 	/* To be implemented */
 }
-#else
-static inline void unwind_trap(struct task_struct *task, unsigned long pc,
-				unsigned long fp, struct stack_trace *trace,
-				const char *loglvl)
-{
-	const struct pt_regs *regs = (const struct pt_regs *) fp;
-	microblaze_unwind_inner(task, regs->pc, regs->r1, regs->r15, trace, loglvl);
-}
-#endif
 
 /**
  * microblaze_unwind_inner - Unwind the stack from the specified point
@@ -215,16 +205,7 @@ static void microblaze_unwind_inner(struct task_struct *task,
 			 * HW exception handler doesn't save all registers,
 			 * so we open-code a special case of unwind_trap()
 			 */
-#ifndef CONFIG_MMU
-			const struct pt_regs *regs =
-				(const struct pt_regs *) fp;
-#endif
 			printk("%sHW EXCEPTION\n", loglvl);
-#ifndef CONFIG_MMU
-			microblaze_unwind_inner(task, regs->r17 - 4,
-						fp + EX_HANDLER_STACK_SIZ,
-						regs->r15, trace, loglvl);
-#endif
 			return;
 		}
 
diff --git a/arch/microblaze/mm/Makefile b/arch/microblaze/mm/Makefile
index 1b16875cea70..cd8a844bf29e 100644
--- a/arch/microblaze/mm/Makefile
+++ b/arch/microblaze/mm/Makefile
@@ -5,5 +5,5 @@
 
 obj-y := consistent.o init.o
 
-obj-$(CONFIG_MMU) += pgtable.o mmu_context.o fault.o
+obj-y += pgtable.o mmu_context.o fault.o
 obj-$(CONFIG_HIGHMEM) += highmem.o
diff --git a/arch/microblaze/mm/consistent.c b/arch/microblaze/mm/consistent.c
index 81dffe43b18c..b7ad4a98636d 100644
--- a/arch/microblaze/mm/consistent.c
+++ b/arch/microblaze/mm/consistent.c
@@ -21,32 +21,3 @@ void arch_dma_prep_coherent(struct page *page, size_t size)
 
 	flush_dcache_range(paddr, paddr + size);
 }
-
-#ifndef CONFIG_MMU
-/*
- * Consistent memory allocators. Used for DMA devices that want to share
- * uncached memory with the processor core.  My crufty no-MMU approach is
- * simple.  In the HW platform we can optionally mirror the DDR up above the
- * processor cacheable region.  So, memory accessed in this mirror region will
- * not be cached.  It's alloced from the same pool as normal memory, but the
- * handle we return is shifted up into the uncached region.  This will no doubt
- * cause big problems if memory allocated here is not also freed properly. -- JW
- *
- * I have to use dcache values because I can't relate on ram size:
- */
-#ifdef CONFIG_XILINX_UNCACHED_SHADOW
-#define UNCACHED_SHADOW_MASK (cpuinfo.dcache_high - cpuinfo.dcache_base + 1)
-#else
-#define UNCACHED_SHADOW_MASK 0
-#endif /* CONFIG_XILINX_UNCACHED_SHADOW */
-
-void *arch_dma_set_uncached(void *ptr, size_t size)
-{
-	unsigned long addr = (unsigned long)ptr;
-
-	addr |= UNCACHED_SHADOW_MASK;
-	if (addr > cpuinfo.dcache_base && addr < cpuinfo.dcache_high)
-		pr_warn("ERROR: Your cache coherent area is CACHED!!!\n");
-	return (void *)addr;
-}
-#endif /* CONFIG_MMU */
diff --git a/arch/microblaze/mm/init.c b/arch/microblaze/mm/init.c
index 45da639bd22c..7129a20881ea 100644
--- a/arch/microblaze/mm/init.c
+++ b/arch/microblaze/mm/init.c
@@ -29,11 +29,6 @@
 /* Use for MMU and noMMU because of PCI generic code */
 int mem_init_done;
 
-#ifndef CONFIG_MMU
-unsigned int __page_offset;
-EXPORT_SYMBOL(__page_offset);
-#endif /* CONFIG_MMU */
-
 char *klimit = _end;
 
 /*
@@ -82,13 +77,11 @@ static void highmem_setup(void)
 static void __init paging_init(void)
 {
 	unsigned long zones_size[MAX_NR_ZONES];
-#ifdef CONFIG_MMU
 	int idx;
 
 	/* Setup fixmaps */
 	for (idx = 0; idx < __end_of_fixed_addresses; idx++)
 		clear_fixmap(idx);
-#endif
 
 	/* Clean every zones */
 	memset(zones_size, 0, sizeof(zones_size));
@@ -108,40 +101,6 @@ static void __init paging_init(void)
 
 void __init setup_memory(void)
 {
-#ifndef CONFIG_MMU
-	u32 kernel_align_start, kernel_align_size;
-	phys_addr_t start, end;
-	u64 i;
-
-	/* Find main memory where is the kernel */
-	for_each_mem_range(i, &start, &end) {
-		memory_start = start;
-		lowmem_size = end - start;
-		if ((memory_start <= (u32)_text) &&
-			((u32)_text <= (memory_start + lowmem_size - 1))) {
-			memory_size = lowmem_size;
-			PAGE_OFFSET = memory_start;
-			pr_info("%s: Main mem: 0x%x, size 0x%08x\n",
-				__func__, (u32) memory_start,
-					(u32) memory_size);
-			break;
-		}
-	}
-
-	if (!memory_start || !memory_size) {
-		panic("%s: Missing memory setting 0x%08x, size=0x%08x\n",
-			__func__, (u32) memory_start, (u32) memory_size);
-	}
-
-	/* reservation of region where is the kernel */
-	kernel_align_start = PAGE_DOWN((u32)_text);
-	/* ALIGN can be remove because _end in vmlinux.lds.S is align */
-	kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start;
-	pr_info("%s: kernel addr:0x%08x-0x%08x size=0x%08x\n",
-		__func__, kernel_align_start, kernel_align_start
-			+ kernel_align_size, kernel_align_size);
-	memblock_reserve(kernel_align_start, kernel_align_size);
-#endif
 	/*
 	 * Kernel:
 	 * start: base phys address of kernel - page align
@@ -181,12 +140,6 @@ void __init mem_init(void)
 	mem_init_done = 1;
 }
 
-#ifndef CONFIG_MMU
-int page_is_ram(unsigned long pfn)
-{
-	return __range_ok(pfn, 0);
-}
-#else
 int page_is_ram(unsigned long pfn)
 {
 	return pfn < max_low_pfn;
@@ -330,8 +283,6 @@ void __init *early_get_page(void)
 				NUMA_NO_NODE);
 }
 
-#endif /* CONFIG_MMU */
-
 void * __ref zalloc_maybe_bootmem(size_t size, gfp_t mask)
 {
 	void *p;
diff --git a/arch/microblaze/pci/pci-common.c b/arch/microblaze/pci/pci-common.c
index 60a58c0015f2..557585f1be41 100644
--- a/arch/microblaze/pci/pci-common.c
+++ b/arch/microblaze/pci/pci-common.c
@@ -325,12 +325,10 @@ int pci_mmap_legacy_page_range(struct pci_bus *bus,
 		 * memory, effectively behaving just like /dev/zero
 		 */
 		if ((offset + size) > hose->isa_mem_size) {
-#ifdef CONFIG_MMU
 			pr_debug("Process %s (pid:%d) mapped non-existing PCI",
 				current->comm, current->pid);
 			pr_debug("legacy memory for 0%04x:%02x\n",
 				pci_domain_nr(bus), bus->number);
-#endif
 			if (vma->vm_flags & VM_SHARED)
 				return shmem_zero_setup(vma);
 			return 0;
-- 
2.29.2


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