Initial commit; kernel source import

arch/metag/mm/Kconfig

@@ -0,0 +1,146 @@
+menu "Memory management options"
+
+config PAGE_OFFSET
+	hex "Kernel page offset address"
+	default "0x40000000"
+	help
+	  This option allows you to set the virtual address at which the
+	  kernel will be mapped to.
+endmenu
+
+config KERNEL_4M_PAGES
+	bool "Map kernel with 4MB pages"
+	depends on METAG_META21_MMU
+	default y
+	help
+	  Map the kernel with large pages to reduce TLB pressure.
+
+choice
+	prompt "User page size"
+	default PAGE_SIZE_4K
+
+config PAGE_SIZE_4K
+	bool "4kB"
+	help
+	  This is the default page size used by all Meta cores.
+
+config PAGE_SIZE_8K
+	bool "8kB"
+	depends on METAG_META21_MMU
+	help
+	  This enables 8kB pages as supported by Meta 2.x and later MMUs.
+
+config PAGE_SIZE_16K
+	bool "16kB"
+	depends on METAG_META21_MMU
+	help
+	  This enables 16kB pages as supported by Meta 2.x and later MMUs.
+
+endchoice
+
+config NUMA
+	bool "Non Uniform Memory Access (NUMA) Support"
+	select ARCH_WANT_NUMA_VARIABLE_LOCALITY
+	help
+	  Some Meta systems have MMU-mappable on-chip memories with
+	  lower latencies than main memory. This enables support for
+	  these blocks by binding them to nodes and allowing
+	  memory policies to be used for prioritizing and controlling
+	  allocation behaviour.
+
+config FORCE_MAX_ZONEORDER
+	int "Maximum zone order"
+	range 10 32
+	default "10"
+	help
+	  The kernel memory allocator divides physically contiguous memory
+	  blocks into "zones", where each zone is a power of two number of
+	  pages.  This option selects the largest power of two that the kernel
+	  keeps in the memory allocator.  If you need to allocate very large
+	  blocks of physically contiguous memory, then you may need to
+	  increase this value.
+
+	  This config option is actually maximum order plus one. For example,
+	  a value of 11 means that the largest free memory block is 2^10 pages.
+
+	  The page size is not necessarily 4KB.  Keep this in mind
+	  when choosing a value for this option.
+
+config METAG_L2C
+	bool "Level 2 Cache Support"
+	depends on METAG_META21
+	help
+	  Press y here to enable support for the Meta Level 2 (L2) cache. This
+	  will enable the cache at start up if it hasn't already been enabled
+	  by the bootloader.
+
+	  If the bootloader enables the L2 you must press y here to ensure the
+	  kernel takes the appropriate actions to keep the cache coherent.
+
+config NODES_SHIFT
+	int
+	default "1"
+	depends on NEED_MULTIPLE_NODES
+
+config ARCH_FLATMEM_ENABLE
+	def_bool y
+	depends on !NUMA
+
+config ARCH_SPARSEMEM_ENABLE
+	def_bool y
+	select SPARSEMEM_STATIC
+
+config ARCH_SPARSEMEM_DEFAULT
+	def_bool y
+
+config ARCH_SELECT_MEMORY_MODEL
+	def_bool y
+
+config SYS_SUPPORTS_HUGETLBFS
+	def_bool y
+	depends on METAG_META21_MMU
+
+choice
+	prompt "HugeTLB page size"
+	depends on METAG_META21_MMU && HUGETLB_PAGE
+	default HUGETLB_PAGE_SIZE_1M
+
+config HUGETLB_PAGE_SIZE_8K
+	bool "8kB"
+	depends on PAGE_SIZE_4K
+
+config HUGETLB_PAGE_SIZE_16K
+	bool "16kB"
+	depends on PAGE_SIZE_4K || PAGE_SIZE_8K
+
+config HUGETLB_PAGE_SIZE_32K
+	bool "32kB"
+
+config HUGETLB_PAGE_SIZE_64K
+	bool "64kB"
+
+config HUGETLB_PAGE_SIZE_128K
+	bool "128kB"
+
+config HUGETLB_PAGE_SIZE_256K
+	bool "256kB"
+
+config HUGETLB_PAGE_SIZE_512K
+	bool "512kB"
+
+config HUGETLB_PAGE_SIZE_1M
+	bool "1MB"
+
+config HUGETLB_PAGE_SIZE_2M
+	bool "2MB"
+
+config HUGETLB_PAGE_SIZE_4M
+	bool "4MB"
+
+endchoice
+
+config METAG_COREMEM
+	bool
+	default y if SUSPEND
+
+source "mm/Kconfig"

arch/metag/mm/Makefile

@@ -0,0 +1,19 @@
+#
+# Makefile for the linux Meta-specific parts of the memory manager.
+#
+
+obj-y				+= cache.o
+obj-y				+= extable.o
+obj-y				+= fault.o
+obj-y				+= init.o
+obj-y				+= ioremap.o
+obj-y				+= maccess.o
+
+mmu-y				:= mmu-meta1.o
+mmu-$(CONFIG_METAG_META21_MMU)	:= mmu-meta2.o
+obj-y				+= $(mmu-y)
+
+obj-$(CONFIG_HIGHMEM)		+= highmem.o
+obj-$(CONFIG_HUGETLB_PAGE)	+= hugetlbpage.o
+obj-$(CONFIG_METAG_L2C)		+= l2cache.o
+obj-$(CONFIG_NUMA)		+= numa.o

arch/metag/mm/cache.c

@@ -0,0 +1,521 @@
+/*
+ * arch/metag/mm/cache.c
+ *
+ * Copyright (C) 2001, 2002, 2005, 2007, 2012 Imagination Technologies.
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License version 2 as published by the
+ * Free Software Foundation.
+ *
+ * Cache control code
+ */
+
+#include <linux/export.h>
+#include <linux/io.h>
+#include <asm/cacheflush.h>
+#include <asm/core_reg.h>
+#include <asm/global_lock.h>
+#include <asm/metag_isa.h>
+#include <asm/metag_mem.h>
+#include <asm/metag_regs.h>
+
+#define DEFAULT_CACHE_WAYS_LOG2	2
+
+/*
+ * Size of a set in the caches. Initialised for default 16K stride, adjusted
+ * according to values passed through TBI global heap segment via LDLK (on ATP)
+ * or config registers (on HTP/MTP)
+ */
+static int dcache_set_shift = METAG_TBI_CACHE_SIZE_BASE_LOG2
+					- DEFAULT_CACHE_WAYS_LOG2;
+static int icache_set_shift = METAG_TBI_CACHE_SIZE_BASE_LOG2
+					- DEFAULT_CACHE_WAYS_LOG2;
+/*
+ * The number of sets in the caches. Initialised for HTP/ATP, adjusted
+ * according to NOMMU setting in config registers
+ */
+static unsigned char dcache_sets_log2 = DEFAULT_CACHE_WAYS_LOG2;
+static unsigned char icache_sets_log2 = DEFAULT_CACHE_WAYS_LOG2;
+
+#ifndef CONFIG_METAG_META12
+/**
+ * metag_lnkget_probe() - Probe whether lnkget/lnkset go around the cache
+ */
+static volatile u32 lnkget_testdata[16] __initdata __aligned(64);
+
+#define LNKGET_CONSTANT 0xdeadbeef
+
+void __init metag_lnkget_probe(void)
+{
+	int temp;
+	long flags;
+
+	/*
+	 * It's conceivable the user has configured a globally coherent cache
+	 * shared with non-Linux hardware threads, so use LOCK2 to prevent them
+	 * from executing and causing cache eviction during the test.
+	 */
+	__global_lock2(flags);
+
+	/* read a value to bring it into the cache */
+	(void)lnkget_testdata[0];
+	lnkget_testdata[0] = 0;
+
+	/* lnkget/lnkset it to modify it */
+	asm volatile(
+		"1:	LNKGETD %0, [%1]\n"
+		"	LNKSETD [%1], %2\n"
+		"	DEFR	%0, TXSTAT\n"
+		"	ANDT	%0, %0, #HI(0x3f000000)\n"
+		"	CMPT	%0, #HI(0x02000000)\n"
+		"	BNZ	1b\n"
+		: "=&d" (temp)
+		: "da" (&lnkget_testdata[0]), "bd" (LNKGET_CONSTANT)
+		: "cc");
+
+	/* re-read it to see if the cached value changed */
+	temp = lnkget_testdata[0];
+
+	__global_unlock2(flags);
+
+	/* flush the cache line to fix any incoherency */
+	__builtin_dcache_flush((void *)&lnkget_testdata[0]);
+
+#if defined(CONFIG_METAG_LNKGET_AROUND_CACHE)
+	/* if the cache is right, LNKGET_AROUND_CACHE is unnecessary */
+	if (temp == LNKGET_CONSTANT)
+		pr_info("LNKGET/SET go through cache but CONFIG_METAG_LNKGET_AROUND_CACHE=y\n");
+#elif defined(CONFIG_METAG_ATOMICITY_LNKGET)
+	/*
+	 * if the cache is wrong, LNKGET_AROUND_CACHE is really necessary
+	 * because the kernel is configured to use LNKGET/SET for atomicity
+	 */
+	WARN(temp != LNKGET_CONSTANT,
+	     "LNKGET/SET go around cache but CONFIG_METAG_LNKGET_AROUND_CACHE=n\n"
+	     "Expect kernel failure as it's used for atomicity primitives\n");
+#elif defined(CONFIG_SMP)
+	/*
+	 * if the cache is wrong, LNKGET_AROUND_CACHE should be used or the
+	 * gateway page won't flush and userland could break.
+	 */
+	WARN(temp != LNKGET_CONSTANT,
+	     "LNKGET/SET go around cache but CONFIG_METAG_LNKGET_AROUND_CACHE=n\n"
+	     "Expect userland failure as it's used for user gateway page\n");
+#else
+	/*
+	 * if the cache is wrong, LNKGET_AROUND_CACHE is set wrong, but it
+	 * doesn't actually matter as it doesn't have any effect on !SMP &&
+	 * !ATOMICITY_LNKGET.
+	 */
+	if (temp != LNKGET_CONSTANT)
+		pr_warn("LNKGET/SET go around cache but CONFIG_METAG_LNKGET_AROUND_CACHE=n\n");
+#endif
+}
+#endif /* !CONFIG_METAG_META12 */
+
+/**
+ * metag_cache_probe() - Probe L1 cache configuration.
+ *
+ * Probe the L1 cache configuration to aid the L1 physical cache flushing
+ * functions.
+ */
+void __init metag_cache_probe(void)
+{
+#ifndef CONFIG_METAG_META12
+	int coreid = metag_in32(METAC_CORE_ID);
+	int config = metag_in32(METAC_CORE_CONFIG2);
+	int cfgcache = coreid & METAC_COREID_CFGCACHE_BITS;
+
+	if (cfgcache == METAC_COREID_CFGCACHE_TYPE0 ||
+	    cfgcache == METAC_COREID_CFGCACHE_PRIVNOMMU) {
+		icache_sets_log2 = 1;
+		dcache_sets_log2 = 1;
+	}
+
+	/* For normal size caches, the smallest size is 4Kb.
+	   For small caches, the smallest size is 64b */
+	icache_set_shift = (config & METAC_CORECFG2_ICSMALL_BIT)
+				? 6 : 12;
+	icache_set_shift += (config & METAC_CORE_C2ICSZ_BITS)
+				>> METAC_CORE_C2ICSZ_S;
+	icache_set_shift -= icache_sets_log2;
+
+	dcache_set_shift = (config & METAC_CORECFG2_DCSMALL_BIT)
+				? 6 : 12;
+	dcache_set_shift += (config & METAC_CORECFG2_DCSZ_BITS)
+				>> METAC_CORECFG2_DCSZ_S;
+	dcache_set_shift -= dcache_sets_log2;
+
+	metag_lnkget_probe();
+#else
+	/* Extract cache sizes from global heap segment */
+	unsigned long val, u;
+	int width, shift, addend;
+	PTBISEG seg;
+
+	seg = __TBIFindSeg(NULL, TBID_SEG(TBID_THREAD_GLOBAL,
+					  TBID_SEGSCOPE_GLOBAL,
+					  TBID_SEGTYPE_HEAP));
+	if (seg != NULL) {
+		val = seg->Data[1];
+
+		/* Work out width of I-cache size bit-field */
+		u = ((unsigned long) METAG_TBI_ICACHE_SIZE_BITS)
+		       >> METAG_TBI_ICACHE_SIZE_S;
+		width = 0;
+		while (u & 1) {
+			width++;
+			u >>= 1;
+		}
+		/* Extract sign-extended size addend value */
+		shift = 32 - (METAG_TBI_ICACHE_SIZE_S + width);
+		addend = (long) ((val & METAG_TBI_ICACHE_SIZE_BITS)
+				 << shift)
+			>> (shift + METAG_TBI_ICACHE_SIZE_S);
+		/* Now calculate I-cache set size */
+		icache_set_shift = (METAG_TBI_CACHE_SIZE_BASE_LOG2
+				    - DEFAULT_CACHE_WAYS_LOG2)
+					+ addend;
+
+		/* Similarly for D-cache */
+		u = ((unsigned long) METAG_TBI_DCACHE_SIZE_BITS)
+		       >> METAG_TBI_DCACHE_SIZE_S;
+		width = 0;
+		while (u & 1) {
+			width++;
+			u >>= 1;
+		}
+		shift = 32 - (METAG_TBI_DCACHE_SIZE_S + width);
+		addend = (long) ((val & METAG_TBI_DCACHE_SIZE_BITS)
+				 << shift)
+			>> (shift + METAG_TBI_DCACHE_SIZE_S);
+		dcache_set_shift = (METAG_TBI_CACHE_SIZE_BASE_LOG2
+				    - DEFAULT_CACHE_WAYS_LOG2)
+					+ addend;
+	}
+#endif
+}
+
+static void metag_phys_data_cache_flush(const void *start)
+{
+	unsigned long flush0, flush1, flush2, flush3;
+	int loops, step;
+	int thread;
+	int part, offset;
+	int set_shift;
+
+	/* Use a sequence of writes to flush the cache region requested */
+	thread = (__core_reg_get(TXENABLE) & TXENABLE_THREAD_BITS)
+					  >> TXENABLE_THREAD_S;
+
+	/* Cache is broken into sets which lie in contiguous RAMs */
+	set_shift = dcache_set_shift;
+
+	/* Move to the base of the physical cache flush region */
+	flush0 = LINSYSCFLUSH_DCACHE_LINE;
+	step   = 64;
+
+	/* Get partition data for this thread */
+	part = metag_in32(SYSC_DCPART0 +
+			      (SYSC_xCPARTn_STRIDE * thread));
+
+	if ((int)start < 0)
+		/* Access Global vs Local partition */
+		part >>= SYSC_xCPARTG_AND_S
+			- SYSC_xCPARTL_AND_S;
+
+	/* Extract offset and move SetOff */
+	offset = (part & SYSC_xCPARTL_OR_BITS)
+			>> SYSC_xCPARTL_OR_S;
+	flush0 += (offset << (set_shift - 4));
+
+	/* Shrink size */
+	part = (part & SYSC_xCPARTL_AND_BITS)
+			>> SYSC_xCPARTL_AND_S;
+	loops = ((part + 1) << (set_shift - 4));
+
+	/* Reduce loops by step of cache line size */
+	loops /= step;
+
+	flush1 = flush0 + (1 << set_shift);
+	flush2 = flush0 + (2 << set_shift);
+	flush3 = flush0 + (3 << set_shift);
+
+	if (dcache_sets_log2 == 1) {
+		flush2 = flush1;
+		flush3 = flush1 + step;
+		flush1 = flush0 + step;
+		step  <<= 1;
+		loops >>= 1;
+	}
+
+	/* Clear loops ways in cache */
+	while (loops-- != 0) {
+		/* Clear the ways. */
+#if 0
+		/*
+		 * GCC doesn't generate very good code for this so we
+		 * provide inline assembly instead.
+		 */
+		metag_out8(0, flush0);
+		metag_out8(0, flush1);
+		metag_out8(0, flush2);
+		metag_out8(0, flush3);
+
+		flush0 += step;
+		flush1 += step;
+		flush2 += step;
+		flush3 += step;
+#else
+		asm volatile (
+			"SETB\t[%0+%4++],%5\n"
+			"SETB\t[%1+%4++],%5\n"
+			"SETB\t[%2+%4++],%5\n"
+			"SETB\t[%3+%4++],%5\n"
+			: "+e" (flush0),
+			  "+e" (flush1),
+			  "+e" (flush2),
+			  "+e" (flush3)
+			: "e" (step), "a" (0));
+#endif
+	}
+}
+
+void metag_data_cache_flush_all(const void *start)
+{
+	if ((metag_in32(SYSC_CACHE_MMU_CONFIG) & SYSC_CMMUCFG_DC_ON_BIT) == 0)
+		/* No need to flush the data cache it's not actually enabled */
+		return;
+
+	metag_phys_data_cache_flush(start);
+}
+
+void metag_data_cache_flush(const void *start, int bytes)
+{
+	unsigned long flush0;
+	int loops, step;
+
+	if ((metag_in32(SYSC_CACHE_MMU_CONFIG) & SYSC_CMMUCFG_DC_ON_BIT) == 0)
+		/* No need to flush the data cache it's not actually enabled */
+		return;
+
+	if (bytes >= 4096) {
+		metag_phys_data_cache_flush(start);
+		return;
+	}
+
+	/* Use linear cache flush mechanism on META IP */
+	flush0 = (int)start;
+	loops  = ((int)start & (DCACHE_LINE_BYTES - 1)) + bytes +
+					(DCACHE_LINE_BYTES - 1);
+	loops  >>= DCACHE_LINE_S;
+
+#define PRIM_FLUSH(addr, offset) do {			\
+	int __addr = ((int) (addr)) + ((offset) * 64);	\
+	__builtin_dcache_flush((void *)(__addr));	\
+	} while (0)
+
+#define LOOP_INC (4*64)
+
+	do {
+		/* By default stop */
+		step = 0;
+
+		switch (loops) {
+		/* Drop Thru Cases! */
+		default:
+			PRIM_FLUSH(flush0, 3);
+			loops -= 4;
+			step = 1;
+		case 3:
+			PRIM_FLUSH(flush0, 2);
+		case 2:
+			PRIM_FLUSH(flush0, 1);
+		case 1:
+			PRIM_FLUSH(flush0, 0);
+			flush0 += LOOP_INC;
+		case 0:
+			break;
+		}
+	} while (step);
+}
+EXPORT_SYMBOL(metag_data_cache_flush);
+
+static void metag_phys_code_cache_flush(const void *start, int bytes)
+{
+	unsigned long flush0, flush1, flush2, flush3, end_set;
+	int loops, step;
+	int thread;
+	int set_shift, set_size;
+	int part, offset;
+
+	/* Use a sequence of writes to flush the cache region requested */
+	thread = (__core_reg_get(TXENABLE) & TXENABLE_THREAD_BITS)
+					  >> TXENABLE_THREAD_S;
+	set_shift = icache_set_shift;
+
+	/* Move to the base of the physical cache flush region */
+	flush0 = LINSYSCFLUSH_ICACHE_LINE;
+	step   = 64;
+
+	/* Get partition code for this thread */
+	part = metag_in32(SYSC_ICPART0 +
+			  (SYSC_xCPARTn_STRIDE * thread));
+
+	if ((int)start < 0)
+		/* Access Global vs Local partition */
+		part >>= SYSC_xCPARTG_AND_S-SYSC_xCPARTL_AND_S;
+
+	/* Extract offset and move SetOff */
+	offset = (part & SYSC_xCPARTL_OR_BITS)
+			>> SYSC_xCPARTL_OR_S;
+	flush0 += (offset << (set_shift - 4));
+
+	/* Shrink size */
+	part = (part & SYSC_xCPARTL_AND_BITS)
+			>> SYSC_xCPARTL_AND_S;
+	loops = ((part + 1) << (set_shift - 4));
+
+	/* Where does the Set end? */
+	end_set = flush0 + loops;
+	set_size = loops;
+
+#ifdef CONFIG_METAG_META12
+	if ((bytes < 4096) && (bytes < loops)) {
+		/* Unreachable on HTP/MTP */
+		/* Only target the sets that could be relavent */
+		flush0 += (loops - step) & ((int) start);
+		loops = (((int) start) & (step-1)) + bytes + step - 1;
+	}
+#endif
+
+	/* Reduce loops by step of cache line size */
+	loops /= step;
+
+	flush1 = flush0 + (1<<set_shift);
+	flush2 = flush0 + (2<<set_shift);
+	flush3 = flush0 + (3<<set_shift);
+
+	if (icache_sets_log2 == 1) {
+		flush2 = flush1;
+		flush3 = flush1 + step;
+		flush1 = flush0 + step;
+#if 0
+		/* flush0 will stop one line early in this case
+		 * (flush1 will do the final line).
+		 * However we don't correct end_set here at the moment
+		 * because it will never wrap on HTP/MTP
+		 */
+		end_set -= step;
+#endif
+		step  <<= 1;
+		loops >>= 1;
+	}
+
+	/* Clear loops ways in cache */
+	while (loops-- != 0) {
+#if 0
+		/*
+		 * GCC doesn't generate very good code for this so we
+		 * provide inline assembly instead.
+		 */
+		/* Clear the ways */
+		metag_out8(0, flush0);
+		metag_out8(0, flush1);
+		metag_out8(0, flush2);
+		metag_out8(0, flush3);
+
+		flush0 += step;
+		flush1 += step;
+		flush2 += step;
+		flush3 += step;
+#else
+		asm volatile (
+			"SETB\t[%0+%4++],%5\n"
+			"SETB\t[%1+%4++],%5\n"
+			"SETB\t[%2+%4++],%5\n"
+			"SETB\t[%3+%4++],%5\n"
+			: "+e" (flush0),
+			  "+e" (flush1),
+			  "+e" (flush2),
+			  "+e" (flush3)
+			: "e" (step), "a" (0));
+#endif
+
+		if (flush0 == end_set) {
+			/* Wrap within Set 0 */
+			flush0 -= set_size;
+			flush1 -= set_size;
+			flush2 -= set_size;
+			flush3 -= set_size;
+		}
+	}
+}
+
+void metag_code_cache_flush_all(const void *start)
+{
+	if ((metag_in32(SYSC_CACHE_MMU_CONFIG) & SYSC_CMMUCFG_IC_ON_BIT) == 0)
+		/* No need to flush the code cache it's not actually enabled */
+		return;
+
+	metag_phys_code_cache_flush(start, 4096);
+}
+EXPORT_SYMBOL(metag_code_cache_flush_all);
+
+void metag_code_cache_flush(const void *start, int bytes)
+{
+#ifndef CONFIG_METAG_META12
+	void *flush;
+	int loops, step;
+#endif /* !CONFIG_METAG_META12 */
+
+	if ((metag_in32(SYSC_CACHE_MMU_CONFIG) & SYSC_CMMUCFG_IC_ON_BIT) == 0)
+		/* No need to flush the code cache it's not actually enabled */
+		return;
+
+#ifdef CONFIG_METAG_META12
+	/* CACHEWD isn't available on Meta1, so always do full cache flush */
+	metag_phys_code_cache_flush(start, bytes);
+
+#else /* CONFIG_METAG_META12 */
+	/* If large size do full physical cache flush */
+	if (bytes >= 4096) {
+		metag_phys_code_cache_flush(start, bytes);
+		return;
+	}
+
+	/* Use linear cache flush mechanism on META IP */
+	flush = (void *)((int)start & ~(ICACHE_LINE_BYTES-1));
+	loops  = ((int)start & (ICACHE_LINE_BYTES-1)) + bytes +
+		(ICACHE_LINE_BYTES-1);
+	loops  >>= ICACHE_LINE_S;
+
+#define PRIM_IFLUSH(addr, offset) \
+	__builtin_meta2_cachewd(((addr) + ((offset) * 64)), CACHEW_ICACHE_BIT)
+
+#define LOOP_INC (4*64)
+
+	do {
+		/* By default stop */
+		step = 0;
+
+		switch (loops) {
+		/* Drop Thru Cases! */
+		default:
+			PRIM_IFLUSH(flush, 3);
+			loops -= 4;
+			step = 1;
+		case 3:
+			PRIM_IFLUSH(flush, 2);
+		case 2:
+			PRIM_IFLUSH(flush, 1);
+		case 1:
+			PRIM_IFLUSH(flush, 0);
+			flush += LOOP_INC;
+		case 0:
+			break;
+		}
+	} while (step);
+#endif /* !CONFIG_METAG_META12 */
+}
+EXPORT_SYMBOL(metag_code_cache_flush);

arch/metag/mm/extable.c

@@ -0,0 +1,15 @@
+
+#include <linux/module.h>
+#include <linux/uaccess.h>
+
+int fixup_exception(struct pt_regs *regs)
+{
+	const struct exception_table_entry *fixup;
+	unsigned long pc = instruction_pointer(regs);
+
+	fixup = search_exception_tables(pc);
+	if (fixup)
+		regs->ctx.CurrPC = fixup->fixup;
+
+	return fixup != NULL;
+}

arch/metag/mm/fault.c

@@ -0,0 +1,239 @@
+/*
+ *  Meta page fault handling.
+ *
+ *  Copyright (C) 2005-2012 Imagination Technologies Ltd.
+ */
+
+#include <linux/mman.h>
+#include <linux/mm.h>
+#include <linux/kernel.h>
+#include <linux/ptrace.h>
+#include <linux/interrupt.h>
+#include <linux/uaccess.h>
+
+#include <asm/tlbflush.h>
+#include <asm/mmu.h>
+#include <asm/traps.h>
+
+/* Clear any pending catch buffer state. */
+static void clear_cbuf_entry(struct pt_regs *regs, unsigned long addr,
+			     unsigned int trapno)
+{
+	PTBICTXEXTCB0 cbuf = regs->extcb0;
+
+	switch (trapno) {
+		/* Instruction fetch faults leave no catch buffer state. */
+	case TBIXXF_SIGNUM_IGF:
+	case TBIXXF_SIGNUM_IPF:
+		return;
+	default:
+		if (cbuf[0].CBAddr == addr) {
+			cbuf[0].CBAddr = 0;
+			cbuf[0].CBFlags &= ~TXCATCH0_FAULT_BITS;
+
+			/* And, as this is the ONLY catch entry, we
+			 * need to clear the cbuf bit from the context!
+			 */
+			regs->ctx.SaveMask &= ~(TBICTX_CBUF_BIT |
+						TBICTX_XCBF_BIT);
+
+			return;
+		}
+		pr_err("Failed to clear cbuf entry!\n");
+	}
+}
+
+int show_unhandled_signals = 1;
+
+int do_page_fault(struct pt_regs *regs, unsigned long address,
+		  unsigned int write_access, unsigned int trapno)
+{
+	struct task_struct *tsk;
+	struct mm_struct *mm;
+	struct vm_area_struct *vma, *prev_vma;
+	siginfo_t info;
+	int fault;
+	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE |
+				(write_access ? FAULT_FLAG_WRITE : 0);
+
+	tsk = current;
+
+	if ((address >= VMALLOC_START) && (address < VMALLOC_END)) {
+		/*
+		 * Synchronize this task's top level page-table
+		 * with the 'reference' page table.
+		 *
+		 * Do _not_ use "tsk" here. We might be inside
+		 * an interrupt in the middle of a task switch..
+		 */
+		int offset = pgd_index(address);
+		pgd_t *pgd, *pgd_k;
+		pud_t *pud, *pud_k;
+		pmd_t *pmd, *pmd_k;
+		pte_t *pte_k;
+
+		pgd = ((pgd_t *)mmu_get_base()) + offset;
+		pgd_k = swapper_pg_dir + offset;
+
+		/* This will never happen with the folded page table. */
+		if (!pgd_present(*pgd)) {
+			if (!pgd_present(*pgd_k))
+				goto bad_area_nosemaphore;
+			set_pgd(pgd, *pgd_k);
+			return 0;
+		}
+
+		pud = pud_offset(pgd, address);
+		pud_k = pud_offset(pgd_k, address);
+		if (!pud_present(*pud_k))
+			goto bad_area_nosemaphore;
+		set_pud(pud, *pud_k);
+
+		pmd = pmd_offset(pud, address);
+		pmd_k = pmd_offset(pud_k, address);
+		if (!pmd_present(*pmd_k))
+			goto bad_area_nosemaphore;
+		set_pmd(pmd, *pmd_k);
+
+		pte_k = pte_offset_kernel(pmd_k, address);
+		if (!pte_present(*pte_k))
+			goto bad_area_nosemaphore;
+
+		/* May only be needed on Chorus2 */
+		flush_tlb_all();
+		return 0;
+	}
+
+	mm = tsk->mm;
+
+	if (in_atomic() || !mm)
+		goto no_context;
+
+retry:
+	down_read(&mm->mmap_sem);
+
+	vma = find_vma_prev(mm, address, &prev_vma);
+
+	if (!vma || address < vma->vm_start)
+		goto check_expansion;
+
+good_area:
+	if (write_access) {
+		if (!(vma->vm_flags & VM_WRITE))
+			goto bad_area;
+	} else {
+		if (!(vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE)))
+			goto bad_area;
+	}
+
+	/*
+	 * If for any reason at all we couldn't handle the fault,
+	 * make sure we exit gracefully rather than endlessly redo
+	 * the fault.
+	 */
+	fault = handle_mm_fault(mm, vma, address, flags);
+
+	if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current))
+		return 0;
+
+	if (unlikely(fault & VM_FAULT_ERROR)) {
+		if (fault & VM_FAULT_OOM)
+			goto out_of_memory;
+		else if (fault & VM_FAULT_SIGBUS)
+			goto do_sigbus;
+		BUG();
+	}
+	if (flags & FAULT_FLAG_ALLOW_RETRY) {
+		if (fault & VM_FAULT_MAJOR)
+			tsk->maj_flt++;
+		else
+			tsk->min_flt++;
+		if (fault & VM_FAULT_RETRY) {
+			flags &= ~FAULT_FLAG_ALLOW_RETRY;
+			flags |= FAULT_FLAG_TRIED;
+
+			/*
+			 * No need to up_read(&mm->mmap_sem) as we would
+			 * have already released it in __lock_page_or_retry
+			 * in mm/filemap.c.
+			 */
+
+			goto retry;
+		}
+	}
+
+	up_read(&mm->mmap_sem);
+	return 0;
+
+check_expansion:
+	vma = prev_vma;
+	if (vma && (expand_stack(vma, address) == 0))
+		goto good_area;
+
+bad_area:
+	up_read(&mm->mmap_sem);
+
+bad_area_nosemaphore:
+	if (user_mode(regs)) {
+		info.si_signo = SIGSEGV;
+		info.si_errno = 0;
+		info.si_code = SEGV_MAPERR;
+		info.si_addr = (__force void __user *)address;
+		info.si_trapno = trapno;
+
+		if (show_unhandled_signals && unhandled_signal(tsk, SIGSEGV) &&
+		    printk_ratelimit()) {
+			pr_info("%s%s[%d]: segfault at %lx pc %08x sp %08x write %d trap %#x (%s)",
+			       task_pid_nr(tsk) > 1 ? KERN_INFO : KERN_EMERG,
+			       tsk->comm, task_pid_nr(tsk), address,
+			       regs->ctx.CurrPC, regs->ctx.AX[0].U0,
+			       write_access, trapno, trap_name(trapno));
+			print_vma_addr(" in ", regs->ctx.CurrPC);
+			print_vma_addr(" rtp in ", regs->ctx.DX[4].U1);
+			printk("\n");
+			show_regs(regs);
+		}
+		force_sig_info(SIGSEGV, &info, tsk);
+		return 1;
+	}
+	goto no_context;
+
+do_sigbus:
+	up_read(&mm->mmap_sem);
+
+	/*
+	 * Send a sigbus, regardless of whether we were in kernel
+	 * or user mode.
+	 */
+	info.si_signo = SIGBUS;
+	info.si_errno = 0;
+	info.si_code = BUS_ADRERR;
+	info.si_addr = (__force void __user *)address;
+	info.si_trapno = trapno;
+	force_sig_info(SIGBUS, &info, tsk);
+
+	/* Kernel mode? Handle exceptions or die */
+	if (!user_mode(regs))
+		goto no_context;
+
+	return 1;
+
+	/*
+	 * We ran out of memory, or some other thing happened to us that made
+	 * us unable to handle the page fault gracefully.
+	 */
+out_of_memory:
+	up_read(&mm->mmap_sem);
+	if (user_mode(regs))
+		do_group_exit(SIGKILL);
+
+no_context:
+	/* Are we prepared to handle this kernel fault?  */
+	if (fixup_exception(regs)) {
+		clear_cbuf_entry(regs, address, trapno);
+		return 1;
+	}
+
+	die("Oops", regs, (write_access << 15) | trapno, address);
+	do_exit(SIGKILL);
+}

arch/metag/mm/highmem.c

@@ -0,0 +1,133 @@
+#include <linux/export.h>
+#include <linux/highmem.h>
+#include <linux/sched.h>
+#include <linux/smp.h>
+#include <linux/interrupt.h>
+#include <asm/fixmap.h>
+#include <asm/tlbflush.h>
+
+static pte_t *kmap_pte;
+
+unsigned long highstart_pfn, highend_pfn;
+
+void *kmap(struct page *page)
+{
+	might_sleep();
+	if (!PageHighMem(page))
+		return page_address(page);
+	return kmap_high(page);
+}
+EXPORT_SYMBOL(kmap);
+
+void kunmap(struct page *page)
+{
+	BUG_ON(in_interrupt());
+	if (!PageHighMem(page))
+		return;
+	kunmap_high(page);
+}
+EXPORT_SYMBOL(kunmap);
+
+/*
+ * kmap_atomic/kunmap_atomic is significantly faster than kmap/kunmap because
+ * no global lock is needed and because the kmap code must perform a global TLB
+ * invalidation when the kmap pool wraps.
+ *
+ * However when holding an atomic kmap is is not legal to sleep, so atomic
+ * kmaps are appropriate for short, tight code paths only.
+ */
+
+void *kmap_atomic(struct page *page)
+{
+	enum fixed_addresses idx;
+	unsigned long vaddr;
+	int type;
+
+	/* even !CONFIG_PREEMPT needs this, for in_atomic in do_page_fault */
+	pagefault_disable();
+	if (!PageHighMem(page))
+		return page_address(page);
+
+	type = kmap_atomic_idx_push();
+	idx = type + KM_TYPE_NR * smp_processor_id();
+	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+#ifdef CONFIG_DEBUG_HIGHMEM
+	BUG_ON(!pte_none(*(kmap_pte - idx)));
+#endif
+	set_pte(kmap_pte - idx, mk_pte(page, PAGE_KERNEL));
+
+	return (void *)vaddr;
+}
+EXPORT_SYMBOL(kmap_atomic);
+
+void __kunmap_atomic(void *kvaddr)
+{
+	unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
+	int idx, type;
+
+	if (kvaddr >= (void *)FIXADDR_START) {
+		type = kmap_atomic_idx();
+		idx = type + KM_TYPE_NR * smp_processor_id();
+
+		/*
+		 * Force other mappings to Oops if they'll try to access this
+		 * pte without first remap it.  Keeping stale mappings around
+		 * is a bad idea also, in case the page changes cacheability
+		 * attributes or becomes a protected page in a hypervisor.
+		 */
+		pte_clear(&init_mm, vaddr, kmap_pte-idx);
+		flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE);
+
+		kmap_atomic_idx_pop();
+	}
+
+	pagefault_enable();
+}
+EXPORT_SYMBOL(__kunmap_atomic);
+
+/*
+ * This is the same as kmap_atomic() but can map memory that doesn't
+ * have a struct page associated with it.
+ */
+void *kmap_atomic_pfn(unsigned long pfn)
+{
+	enum fixed_addresses idx;
+	unsigned long vaddr;
+	int type;
+
+	pagefault_disable();
+
+	type = kmap_atomic_idx_push();
+	idx = type + KM_TYPE_NR * smp_processor_id();
+	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+#ifdef CONFIG_DEBUG_HIGHMEM
+	BUG_ON(!pte_none(*(kmap_pte - idx)));
+#endif
+	set_pte(kmap_pte - idx, pfn_pte(pfn, PAGE_KERNEL));
+	flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE);
+
+	return (void *)vaddr;
+}
+
+struct page *kmap_atomic_to_page(void *ptr)
+{
+	unsigned long vaddr = (unsigned long)ptr;
+	int idx;
+	pte_t *pte;
+
+	if (vaddr < FIXADDR_START)
+		return virt_to_page(ptr);
+
+	idx = virt_to_fix(vaddr);
+	pte = kmap_pte - (idx - FIX_KMAP_BEGIN);
+	return pte_page(*pte);
+}
+
+void __init kmap_init(void)
+{
+	unsigned long kmap_vstart;
+
+	/* cache the first kmap pte */
+	kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
+	kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
+}

arch/metag/mm/hugetlbpage.c

@@ -0,0 +1,259 @@
+/*
+ * arch/metag/mm/hugetlbpage.c
+ *
+ * METAG HugeTLB page support.
+ *
+ * Cloned from SuperH
+ *
+ * Cloned from sparc64 by Paul Mundt.
+ *
+ * Copyright (C) 2002, 2003 David S. Miller (davem@redhat.com)
+ */
+
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/hugetlb.h>
+#include <linux/pagemap.h>
+#include <linux/sysctl.h>
+
+#include <asm/mman.h>
+#include <asm/pgalloc.h>
+#include <asm/tlb.h>
+#include <asm/tlbflush.h>
+#include <asm/cacheflush.h>
+
+/*
+ * If the arch doesn't supply something else, assume that hugepage
+ * size aligned regions are ok without further preparation.
+ */
+int prepare_hugepage_range(struct file *file, unsigned long addr,
+						unsigned long len)
+{
+	struct mm_struct *mm = current->mm;
+	struct hstate *h = hstate_file(file);
+	struct vm_area_struct *vma;
+
+	if (len & ~huge_page_mask(h))
+		return -EINVAL;
+	if (addr & ~huge_page_mask(h))
+		return -EINVAL;
+	if (TASK_SIZE - len < addr)
+		return -EINVAL;
+
+	vma = find_vma(mm, ALIGN_HUGEPT(addr));
+	if (vma && !(vma->vm_flags & MAP_HUGETLB))
+		return -EINVAL;
+
+	vma = find_vma(mm, addr);
+	if (vma) {
+		if (addr + len > vma->vm_start)
+			return -EINVAL;
+		if (!(vma->vm_flags & MAP_HUGETLB) &&
+		    (ALIGN_HUGEPT(addr + len) > vma->vm_start))
+			return -EINVAL;
+	}
+	return 0;
+}
+
+pte_t *huge_pte_alloc(struct mm_struct *mm,
+			unsigned long addr, unsigned long sz)
+{
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+	pte_t *pte;
+
+	pgd = pgd_offset(mm, addr);
+	pud = pud_offset(pgd, addr);
+	pmd = pmd_offset(pud, addr);
+	pte = pte_alloc_map(mm, NULL, pmd, addr);
+	pgd->pgd &= ~_PAGE_SZ_MASK;
+	pgd->pgd |= _PAGE_SZHUGE;
+
+	return pte;
+}
+
+pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
+{
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+	pte_t *pte = NULL;
+
+	pgd = pgd_offset(mm, addr);
+	pud = pud_offset(pgd, addr);
+	pmd = pmd_offset(pud, addr);
+	pte = pte_offset_kernel(pmd, addr);
+
+	return pte;
+}
+
+int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
+{
+	return 0;
+}
+
+struct page *follow_huge_addr(struct mm_struct *mm,
+			      unsigned long address, int write)
+{
+	return ERR_PTR(-EINVAL);
+}
+
+int pmd_huge(pmd_t pmd)
+{
+	return pmd_page_shift(pmd) > PAGE_SHIFT;
+}
+
+int pud_huge(pud_t pud)
+{
+	return 0;
+}
+
+struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
+			     pmd_t *pmd, int write)
+{
+	return NULL;
+}
+
+#ifdef HAVE_ARCH_HUGETLB_UNMAPPED_AREA
+
+/*
+ * Look for an unmapped area starting after another hugetlb vma.
+ * There are guaranteed to be no huge pte's spare if all the huge pages are
+ * full size (4MB), so in that case compile out this search.
+ */
+#if HPAGE_SHIFT == HUGEPT_SHIFT
+static inline unsigned long
+hugetlb_get_unmapped_area_existing(unsigned long len)
+{
+	return 0;
+}
+#else
+static unsigned long
+hugetlb_get_unmapped_area_existing(unsigned long len)
+{
+	struct mm_struct *mm = current->mm;
+	struct vm_area_struct *vma;
+	unsigned long start_addr, addr;
+	int after_huge;
+
+	if (mm->context.part_huge) {
+		start_addr = mm->context.part_huge;
+		after_huge = 1;
+	} else {
+		start_addr = TASK_UNMAPPED_BASE;
+		after_huge = 0;
+	}
+new_search:
+	addr = start_addr;
+
+	for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
+		if ((!vma && !after_huge) || TASK_SIZE - len < addr) {
+			/*
+			 * Start a new search - just in case we missed
+			 * some holes.
+			 */
+			if (start_addr != TASK_UNMAPPED_BASE) {
+				start_addr = TASK_UNMAPPED_BASE;
+				goto new_search;
+			}
+			return 0;
+		}
+		/* skip ahead if we've aligned right over some vmas */
+		if (vma && vma->vm_end <= addr)
+			continue;
+		/* space before the next vma? */
+		if (after_huge && (!vma || ALIGN_HUGEPT(addr + len)
+			    <= vma->vm_start)) {
+			unsigned long end = addr + len;
+			if (end & HUGEPT_MASK)
+				mm->context.part_huge = end;
+			else if (addr == mm->context.part_huge)
+				mm->context.part_huge = 0;
+			return addr;
+		}
+		if (vma && (vma->vm_flags & MAP_HUGETLB)) {
+			/* space after a huge vma in 2nd level page table? */
+			if (vma->vm_end & HUGEPT_MASK) {
+				after_huge = 1;
+				/* no need to align to the next PT block */
+				addr = vma->vm_end;
+				continue;
+			}
+		}
+		after_huge = 0;
+		addr = ALIGN_HUGEPT(vma->vm_end);
+	}
+}
+#endif
+
+/* Do a full search to find an area without any nearby normal pages. */
+static unsigned long
+hugetlb_get_unmapped_area_new_pmd(unsigned long len)
+{
+	struct vm_unmapped_area_info info;
+
+	info.flags = 0;
+	info.length = len;
+	info.low_limit = TASK_UNMAPPED_BASE;
+	info.high_limit = TASK_SIZE;
+	info.align_mask = PAGE_MASK & HUGEPT_MASK;
+	info.align_offset = 0;
+	return vm_unmapped_area(&info);
+}
+
+unsigned long
+hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
+		unsigned long len, unsigned long pgoff, unsigned long flags)
+{
+	struct hstate *h = hstate_file(file);
+
+	if (len & ~huge_page_mask(h))
+		return -EINVAL;
+	if (len > TASK_SIZE)
+		return -ENOMEM;
+
+	if (flags & MAP_FIXED) {
+		if (prepare_hugepage_range(file, addr, len))
+			return -EINVAL;
+		return addr;
+	}
+
+	if (addr) {
+		addr = ALIGN(addr, huge_page_size(h));
+		if (!prepare_hugepage_range(file, addr, len))
+			return addr;
+	}
+
+	/*
+	 * Look for an existing hugetlb vma with space after it (this is to to
+	 * minimise fragmentation caused by huge pages.
+	 */
+	addr = hugetlb_get_unmapped_area_existing(len);
+	if (addr)
+		return addr;
+
+	/*
+	 * Find an unmapped naturally aligned set of 4MB blocks that we can use
+	 * for huge pages.
+	 */
+	return hugetlb_get_unmapped_area_new_pmd(len);
+}
+
+#endif /*HAVE_ARCH_HUGETLB_UNMAPPED_AREA*/
+
+/* necessary for boot time 4MB huge page allocation */
+static __init int setup_hugepagesz(char *opt)
+{
+	unsigned long ps = memparse(opt, &opt);
+	if (ps == (1 << HPAGE_SHIFT)) {
+		hugetlb_add_hstate(HPAGE_SHIFT - PAGE_SHIFT);
+	} else {
+		pr_err("hugepagesz: Unsupported page size %lu M\n",
+		       ps >> 20);
+		return 0;
+	}
+	return 1;
+}
+__setup("hugepagesz=", setup_hugepagesz);

arch/metag/mm/init.c

@@ -0,0 +1,434 @@
+/*
+ *  Copyright (C) 2005,2006,2007,2008,2009,2010 Imagination Technologies
+ *
+ */
+
+#include <linux/export.h>
+#include <linux/mm.h>
+#include <linux/swap.h>
+#include <linux/init.h>
+#include <linux/bootmem.h>
+#include <linux/pagemap.h>
+#include <linux/percpu.h>
+#include <linux/memblock.h>
+#include <linux/initrd.h>
+#include <linux/of_fdt.h>
+
+#include <asm/setup.h>
+#include <asm/page.h>
+#include <asm/pgalloc.h>
+#include <asm/mmu.h>
+#include <asm/mmu_context.h>
+#include <asm/sections.h>
+#include <asm/tlb.h>
+#include <asm/user_gateway.h>
+#include <asm/mmzone.h>
+#include <asm/fixmap.h>
+
+unsigned long pfn_base;
+EXPORT_SYMBOL(pfn_base);
+
+pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_data;
+
+unsigned long empty_zero_page;
+EXPORT_SYMBOL(empty_zero_page);
+
+extern char __user_gateway_start;
+extern char __user_gateway_end;
+
+void *gateway_page;
+
+/*
+ * Insert the gateway page into a set of page tables, creating the
+ * page tables if necessary.
+ */
+static void insert_gateway_page(pgd_t *pgd, unsigned long address)
+{
+	pud_t *pud;
+	pmd_t *pmd;
+	pte_t *pte;
+
+	BUG_ON(!pgd_present(*pgd));
+
+	pud = pud_offset(pgd, address);
+	BUG_ON(!pud_present(*pud));
+
+	pmd = pmd_offset(pud, address);
+	if (!pmd_present(*pmd)) {
+		pte = alloc_bootmem_pages(PAGE_SIZE);
+		set_pmd(pmd, __pmd(_PAGE_TABLE | __pa(pte)));
+	}
+
+	pte = pte_offset_kernel(pmd, address);
+	set_pte(pte, pfn_pte(__pa(gateway_page) >> PAGE_SHIFT, PAGE_READONLY));
+}
+
+/* Alloc and map a page in a known location accessible to userspace. */
+static void __init user_gateway_init(void)
+{
+	unsigned long address = USER_GATEWAY_PAGE;
+	int offset = pgd_index(address);
+	pgd_t *pgd;
+
+	gateway_page = alloc_bootmem_pages(PAGE_SIZE);
+
+	pgd = swapper_pg_dir + offset;
+	insert_gateway_page(pgd, address);
+
+#ifdef CONFIG_METAG_META12
+	/*
+	 * Insert the gateway page into our current page tables even
+	 * though we've already inserted it into our reference page
+	 * table (swapper_pg_dir). This is because with a META1 mmu we
+	 * copy just the user address range and not the gateway page
+	 * entry on context switch, see switch_mmu().
+	 */
+	pgd = (pgd_t *)mmu_get_base() + offset;
+	insert_gateway_page(pgd, address);
+#endif /* CONFIG_METAG_META12 */
+
+	BUG_ON((&__user_gateway_end - &__user_gateway_start) > PAGE_SIZE);
+
+	gateway_page += (address & ~PAGE_MASK);
+
+	memcpy(gateway_page, &__user_gateway_start,
+	       &__user_gateway_end - &__user_gateway_start);
+
+	/*
+	 * We don't need to flush the TLB here, there should be no mapping
+	 * present at boot for this address and only valid mappings are in
+	 * the TLB (apart from on Meta 1.x, but those cached invalid
+	 * mappings should be impossible to hit here).
+	 *
+	 * We don't flush the code cache here even though we have written
+	 * code through the data cache and they may not be coherent. At
+	 * this point we assume there is no stale data in the code cache
+	 * for this address so there is no need to flush.
+	 */
+}
+
+static void __init allocate_pgdat(unsigned int nid)
+{
+	unsigned long start_pfn, end_pfn;
+#ifdef CONFIG_NEED_MULTIPLE_NODES
+	unsigned long phys;
+#endif
+
+	get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
+
+#ifdef CONFIG_NEED_MULTIPLE_NODES
+	phys = __memblock_alloc_base(sizeof(struct pglist_data),
+				SMP_CACHE_BYTES, end_pfn << PAGE_SHIFT);
+	/* Retry with all of system memory */
+	if (!phys)
+		phys = __memblock_alloc_base(sizeof(struct pglist_data),
+					     SMP_CACHE_BYTES,
+					     memblock_end_of_DRAM());
+	if (!phys)
+		panic("Can't allocate pgdat for node %d\n", nid);
+
+	NODE_DATA(nid) = __va(phys);
+	memset(NODE_DATA(nid), 0, sizeof(struct pglist_data));
+
+	NODE_DATA(nid)->bdata = &bootmem_node_data[nid];
+#endif
+
+	NODE_DATA(nid)->node_start_pfn = start_pfn;
+	NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn;
+}
+
+static void __init bootmem_init_one_node(unsigned int nid)
+{
+	unsigned long total_pages, paddr;
+	unsigned long end_pfn;
+	struct pglist_data *p;
+
+	p = NODE_DATA(nid);
+
+	/* Nothing to do.. */
+	if (!p->node_spanned_pages)
+		return;
+
+	end_pfn = p->node_start_pfn + p->node_spanned_pages;
+#ifdef CONFIG_HIGHMEM
+	if (end_pfn > max_low_pfn)
+		end_pfn = max_low_pfn;
+#endif
+
+	total_pages = bootmem_bootmap_pages(end_pfn - p->node_start_pfn);
+
+	paddr = memblock_alloc(total_pages << PAGE_SHIFT, PAGE_SIZE);
+	if (!paddr)
+		panic("Can't allocate bootmap for nid[%d]\n", nid);
+
+	init_bootmem_node(p, paddr >> PAGE_SHIFT, p->node_start_pfn, end_pfn);
+
+	free_bootmem_with_active_regions(nid, end_pfn);
+
+	/*
+	 * XXX Handle initial reservations for the system memory node
+	 * only for the moment, we'll refactor this later for handling
+	 * reservations in other nodes.
+	 */
+	if (nid == 0) {
+		struct memblock_region *reg;
+
+		/* Reserve the sections we're already using. */
+		for_each_memblock(reserved, reg) {
+			unsigned long size = reg->size;
+
+#ifdef CONFIG_HIGHMEM
+			/* ...but not highmem */
+			if (PFN_DOWN(reg->base) >= highstart_pfn)
+				continue;
+
+			if (PFN_UP(reg->base + size) > highstart_pfn)
+				size = (highstart_pfn - PFN_DOWN(reg->base))
+				       << PAGE_SHIFT;
+#endif
+
+			reserve_bootmem(reg->base, size, BOOTMEM_DEFAULT);
+		}
+	}
+
+	sparse_memory_present_with_active_regions(nid);
+}
+
+static void __init do_init_bootmem(void)
+{
+	struct memblock_region *reg;
+	int i;
+
+	/* Add active regions with valid PFNs. */
+	for_each_memblock(memory, reg) {
+		unsigned long start_pfn, end_pfn;
+		start_pfn = memblock_region_memory_base_pfn(reg);
+		end_pfn = memblock_region_memory_end_pfn(reg);
+		memblock_set_node(PFN_PHYS(start_pfn),
+				  PFN_PHYS(end_pfn - start_pfn), 0);
+	}
+
+	/* All of system RAM sits in node 0 for the non-NUMA case */
+	allocate_pgdat(0);
+	node_set_online(0);
+
+	soc_mem_setup();
+
+	for_each_online_node(i)
+		bootmem_init_one_node(i);
+
+	sparse_init();
+}
+
+extern char _heap_start[];
+
+static void __init init_and_reserve_mem(void)
+{
+	unsigned long start_pfn, heap_start;
+	u64 base = min_low_pfn << PAGE_SHIFT;
+	u64 size = (max_low_pfn << PAGE_SHIFT) - base;
+
+	heap_start = (unsigned long) &_heap_start;
+
+	memblock_add(base, size);
+
+	/*
+	 * Partially used pages are not usable - thus
+	 * we are rounding upwards:
+	 */
+	start_pfn = PFN_UP(__pa(heap_start));
+
+	/*
+	 * Reserve the kernel text.
+	 */
+	memblock_reserve(base, (PFN_PHYS(start_pfn) + PAGE_SIZE - 1) - base);
+
+#ifdef CONFIG_HIGHMEM
+	/*
+	 * Add & reserve highmem, so page structures are initialised.
+	 */
+	base = highstart_pfn << PAGE_SHIFT;
+	size = (highend_pfn << PAGE_SHIFT) - base;
+	if (size) {
+		memblock_add(base, size);
+		memblock_reserve(base, size);
+	}
+#endif
+}
+
+#ifdef CONFIG_HIGHMEM
+/*
+ * Ensure we have allocated page tables in swapper_pg_dir for the
+ * fixed mappings range from 'start' to 'end'.
+ */
+static void __init allocate_pgtables(unsigned long start, unsigned long end)
+{
+	pgd_t *pgd;
+	pmd_t *pmd;
+	pte_t *pte;
+	int i, j;
+	unsigned long vaddr;
+
+	vaddr = start;
+	i = pgd_index(vaddr);
+	j = pmd_index(vaddr);
+	pgd = swapper_pg_dir + i;
+
+	for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) {
+		pmd = (pmd_t *)pgd;
+		for (; (j < PTRS_PER_PMD) && (vaddr != end); pmd++, j++) {
+			vaddr += PMD_SIZE;
+
+			if (!pmd_none(*pmd))
+				continue;
+
+			pte = (pte_t *)alloc_bootmem_low_pages(PAGE_SIZE);
+			pmd_populate_kernel(&init_mm, pmd, pte);
+		}
+		j = 0;
+	}
+}
+
+static void __init fixedrange_init(void)
+{
+	unsigned long vaddr, end;
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+	pte_t *pte;
+
+	/*
+	 * Fixed mappings:
+	 */
+	vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
+	end = (FIXADDR_TOP + PMD_SIZE - 1) & PMD_MASK;
+	allocate_pgtables(vaddr, end);
+
+	/*
+	 * Permanent kmaps:
+	 */
+	vaddr = PKMAP_BASE;
+	allocate_pgtables(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP);
+
+	pgd = swapper_pg_dir + pgd_index(vaddr);
+	pud = pud_offset(pgd, vaddr);
+	pmd = pmd_offset(pud, vaddr);
+	pte = pte_offset_kernel(pmd, vaddr);
+	pkmap_page_table = pte;
+}
+#endif /* CONFIG_HIGHMEM */
+
+/*
+ * paging_init() continues the virtual memory environment setup which
+ * was begun by the code in arch/metag/kernel/setup.c.
+ */
+void __init paging_init(unsigned long mem_end)
+{
+	unsigned long max_zone_pfns[MAX_NR_ZONES];
+	int nid;
+
+	init_and_reserve_mem();
+
+	memblock_allow_resize();
+
+	memblock_dump_all();
+
+	nodes_clear(node_online_map);
+
+	init_new_context(&init_task, &init_mm);
+
+	memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
+
+	do_init_bootmem();
+	mmu_init(mem_end);
+
+#ifdef CONFIG_HIGHMEM
+	fixedrange_init();
+	kmap_init();
+#endif
+
+	/* Initialize the zero page to a bootmem page, already zeroed. */
+	empty_zero_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
+
+	user_gateway_init();
+
+	memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
+
+	for_each_online_node(nid) {
+		pg_data_t *pgdat = NODE_DATA(nid);
+		unsigned long low, start_pfn;
+
+		start_pfn = pgdat->bdata->node_min_pfn;
+		low = pgdat->bdata->node_low_pfn;
+
+		if (max_zone_pfns[ZONE_NORMAL] < low)
+			max_zone_pfns[ZONE_NORMAL] = low;
+
+#ifdef CONFIG_HIGHMEM
+		max_zone_pfns[ZONE_HIGHMEM] = highend_pfn;
+#endif
+		pr_info("Node %u: start_pfn = 0x%lx, low = 0x%lx\n",
+			nid, start_pfn, low);
+	}
+
+	free_area_init_nodes(max_zone_pfns);
+}
+
+void __init mem_init(void)
+{
+	int nid;
+
+#ifdef CONFIG_HIGHMEM
+	unsigned long tmp;
+
+	/*
+	 * Explicitly reset zone->managed_pages because highmem pages are
+	 * freed before calling free_all_bootmem_node();
+	 */
+	reset_all_zones_managed_pages();
+	for (tmp = highstart_pfn; tmp < highend_pfn; tmp++)
+		free_highmem_page(pfn_to_page(tmp));
+	num_physpages += totalhigh_pages;
+#endif /* CONFIG_HIGHMEM */
+
+	for_each_online_node(nid) {
+		pg_data_t *pgdat = NODE_DATA(nid);
+		unsigned long node_pages = 0;
+
+		num_physpages += pgdat->node_present_pages;
+
+		if (pgdat->node_spanned_pages)
+			node_pages = free_all_bootmem_node(pgdat);
+
+		totalram_pages += node_pages;
+	}
+
+	pr_info("Memory: %luk/%luk available\n",
+		(unsigned long)nr_free_pages() << (PAGE_SHIFT - 10),
+		num_physpages << (PAGE_SHIFT - 10));
+
+	show_mem(0);
+
+	return;
+}
+
+void free_initmem(void)
+{
+	free_initmem_default(POISON_FREE_INITMEM);
+}
+
+#ifdef CONFIG_BLK_DEV_INITRD
+void free_initrd_mem(unsigned long start, unsigned long end)
+{
+	free_reserved_area(start, end, POISON_FREE_INITMEM, "initrd");
+}
+#endif
+
+#ifdef CONFIG_OF_FLATTREE
+void __init early_init_dt_setup_initrd_arch(unsigned long start,
+					    unsigned long end)
+{
+	pr_err("%s(%lx, %lx)\n",
+	       __func__, start, end);
+}
+#endif /* CONFIG_OF_FLATTREE */

arch/metag/mm/ioremap.c

@@ -0,0 +1,89 @@
+/*
+ * Re-map IO memory to kernel address space so that we can access it.
+ * Needed for memory-mapped I/O devices mapped outside our normal DRAM
+ * window (that is, all memory-mapped I/O devices).
+ *
+ * Copyright (C) 1995,1996 Linus Torvalds
+ *
+ * Meta port based on CRIS-port by Axis Communications AB
+ */
+
+#include <linux/vmalloc.h>
+#include <linux/io.h>
+#include <linux/export.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+
+#include <asm/pgtable.h>
+
+/*
+ * Remap an arbitrary physical address space into the kernel virtual
+ * address space. Needed when the kernel wants to access high addresses
+ * directly.
+ *
+ * NOTE! We need to allow non-page-aligned mappings too: we will obviously
+ * have to convert them into an offset in a page-aligned mapping, but the
+ * caller shouldn't need to know that small detail.
+ */
+void __iomem *__ioremap(unsigned long phys_addr, size_t size,
+			unsigned long flags)
+{
+	unsigned long addr;
+	struct vm_struct *area;
+	unsigned long offset, last_addr;
+	pgprot_t prot;
+
+	/* Don't allow wraparound or zero size */
+	last_addr = phys_addr + size - 1;
+	if (!size || last_addr < phys_addr)
+		return NULL;
+
+	/* Custom region addresses are accessible and uncached by default. */
+	if (phys_addr >= LINSYSCUSTOM_BASE &&
+	    phys_addr < (LINSYSCUSTOM_BASE + LINSYSCUSTOM_LIMIT))
+		return (__force void __iomem *) phys_addr;
+
+	/*
+	 * Mappings have to be page-aligned
+	 */
+	offset = phys_addr & ~PAGE_MASK;
+	phys_addr &= PAGE_MASK;
+	size = PAGE_ALIGN(last_addr+1) - phys_addr;
+	prot = __pgprot(_PAGE_PRESENT | _PAGE_WRITE | _PAGE_DIRTY |
+			_PAGE_ACCESSED | _PAGE_KERNEL | _PAGE_CACHE_WIN0 |
+			flags);
+
+	/*
+	 * Ok, go for it..
+	 */
+	area = get_vm_area(size, VM_IOREMAP);
+	if (!area)
+		return NULL;
+	area->phys_addr = phys_addr;
+	addr = (unsigned long) area->addr;
+	if (ioremap_page_range(addr, addr + size, phys_addr, prot)) {
+		vunmap((void *) addr);
+		return NULL;
+	}
+	return (__force void __iomem *) (offset + (char *)addr);
+}
+EXPORT_SYMBOL(__ioremap);
+
+void __iounmap(void __iomem *addr)
+{
+	struct vm_struct *p;
+
+	if ((__force unsigned long)addr >= LINSYSCUSTOM_BASE &&
+	    (__force unsigned long)addr < (LINSYSCUSTOM_BASE +
+					   LINSYSCUSTOM_LIMIT))
+		return;
+
+	p = remove_vm_area((void *)(PAGE_MASK & (unsigned long __force)addr));
+	if (unlikely(!p)) {
+		pr_err("iounmap: bad address %p\n", addr);
+		return;
+	}
+
+	kfree(p);
+}
+EXPORT_SYMBOL(__iounmap);

arch/metag/mm/l2cache.c

@@ -0,0 +1,192 @@
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+
+#include <asm/l2cache.h>
+#include <asm/metag_isa.h>
+
+/* If non-0, then initialise the L2 cache */
+static int l2cache_init = 1;
+/* If non-0, then initialise the L2 cache prefetch */
+static int l2cache_init_pf = 1;
+
+int l2c_pfenable;
+
+static volatile u32 l2c_testdata[16] __initdata __aligned(64);
+
+static int __init parse_l2cache(char *p)
+{
+	char *cp = p;
+
+	if (get_option(&cp, &l2cache_init) != 1) {
+		pr_err("Bad l2cache parameter (%s)\n", p);
+		return 1;
+	}
+	return 0;
+}
+early_param("l2cache", parse_l2cache);
+
+static int __init parse_l2cache_pf(char *p)
+{
+	char *cp = p;
+
+	if (get_option(&cp, &l2cache_init_pf) != 1) {
+		pr_err("Bad l2cache_pf parameter (%s)\n", p);
+		return 1;
+	}
+	return 0;
+}
+early_param("l2cache_pf", parse_l2cache_pf);
+
+static int __init meta_l2c_setup(void)
+{
+	/*
+	 * If the L2 cache isn't even present, don't do anything, but say so in
+	 * the log.
+	 */
+	if (!meta_l2c_is_present()) {
+		pr_info("L2 Cache: Not present\n");
+		return 0;
+	}
+
+	/*
+	 * Check whether the line size is recognised.
+	 */
+	if (!meta_l2c_linesize()) {
+		pr_warn_once("L2 Cache: unknown line size id (config=0x%08x)\n",
+			     meta_l2c_config());
+	}
+
+	/*
+	 * Initialise state.
+	 */
+	l2c_pfenable = _meta_l2c_pf_is_enabled();
+
+	/*
+	 * Enable the L2 cache and print to log whether it was already enabled
+	 * by the bootloader.
+	 */
+	if (l2cache_init) {
+		pr_info("L2 Cache: Enabling... ");
+		if (meta_l2c_enable())
+			pr_cont("already enabled\n");
+		else
+			pr_cont("done\n");
+	} else {
+		pr_info("L2 Cache: Not enabling\n");
+	}
+
+	/*
+	 * Enable L2 cache prefetch.
+	 */
+	if (l2cache_init_pf) {
+		pr_info("L2 Cache: Enabling prefetch... ");
+		if (meta_l2c_pf_enable(1))
+			pr_cont("already enabled\n");
+		else
+			pr_cont("done\n");
+	} else {
+		pr_info("L2 Cache: Not enabling prefetch\n");
+	}
+
+	return 0;
+}
+core_initcall(meta_l2c_setup);
+
+int meta_l2c_disable(void)
+{
+	unsigned long flags;
+	int en;
+
+	if (!meta_l2c_is_present())
+		return 1;
+
+	/*
+	 * Prevent other threads writing during the writeback, otherwise the
+	 * writes will get "lost" when the L2 is disabled.
+	 */
+	__global_lock2(flags);
+	en = meta_l2c_is_enabled();
+	if (likely(en)) {
+		_meta_l2c_pf_enable(0);
+		wr_fence();
+		_meta_l2c_purge();
+		_meta_l2c_enable(0);
+	}
+	__global_unlock2(flags);
+
+	return !en;
+}
+
+int meta_l2c_enable(void)
+{
+	unsigned long flags;
+	int en;
+
+	if (!meta_l2c_is_present())
+		return 0;
+
+	/*
+	 * Init (clearing the L2) can happen while the L2 is disabled, so other
+	 * threads are safe to continue executing, however we must not init the
+	 * cache if it's already enabled (dirty lines would be discarded), so
+	 * this operation should still be atomic with other threads.
+	 */
+	__global_lock1(flags);
+	en = meta_l2c_is_enabled();
+	if (likely(!en)) {
+		_meta_l2c_init();
+		_meta_l2c_enable(1);
+		_meta_l2c_pf_enable(l2c_pfenable);
+	}
+	__global_unlock1(flags);
+
+	return en;
+}
+
+int meta_l2c_pf_enable(int pfenable)
+{
+	unsigned long flags;
+	int en = l2c_pfenable;
+
+	if (!meta_l2c_is_present())
+		return 0;
+
+	/*
+	 * We read modify write the enable register, so this operation must be
+	 * atomic with other threads.
+	 */
+	__global_lock1(flags);
+	en = l2c_pfenable;
+	l2c_pfenable = pfenable;
+	if (meta_l2c_is_enabled())
+		_meta_l2c_pf_enable(pfenable);
+	__global_unlock1(flags);
+
+	return en;
+}
+
+int meta_l2c_flush(void)
+{
+	unsigned long flags;
+	int en;
+
+	/*
+	 * Prevent other threads writing during the writeback. This also
+	 * involves read modify writes.
+	 */
+	__global_lock2(flags);
+	en = meta_l2c_is_enabled();
+	if (likely(en)) {
+		_meta_l2c_pf_enable(0);
+		wr_fence();
+		_meta_l2c_purge();
+		_meta_l2c_enable(0);
+		_meta_l2c_init();
+		_meta_l2c_enable(1);
+		_meta_l2c_pf_enable(l2c_pfenable);
+	}
+	__global_unlock2(flags);
+
+	return !en;
+}

arch/metag/mm/maccess.c

@@ -0,0 +1,68 @@
+/*
+ * safe read and write memory routines callable while atomic
+ *
+ * Copyright 2012 Imagination Technologies
+ */
+
+#include <linux/uaccess.h>
+#include <asm/io.h>
+
+/*
+ * The generic probe_kernel_write() uses the user copy code which can split the
+ * writes if the source is unaligned, and repeats writes to make exceptions
+ * precise. We override it here to avoid these things happening to memory mapped
+ * IO memory where they could have undesired effects.
+ * Due to the use of CACHERD instruction this only works on Meta2 onwards.
+ */
+#ifdef CONFIG_METAG_META21
+long probe_kernel_write(void *dst, const void *src, size_t size)
+{
+	unsigned long ldst = (unsigned long)dst;
+	void __iomem *iodst = (void __iomem *)dst;
+	unsigned long lsrc = (unsigned long)src;
+	const u8 *psrc = (u8 *)src;
+	unsigned int pte, i;
+	u8 bounce[8] __aligned(8);
+
+	if (!size)
+		return 0;
+
+	/* Use the write combine bit to decide is the destination is MMIO. */
+	pte = __builtin_meta2_cacherd(dst);
+
+	/* Check the mapping is valid and writeable. */
+	if ((pte & (MMCU_ENTRY_WR_BIT | MMCU_ENTRY_VAL_BIT))
+	    != (MMCU_ENTRY_WR_BIT | MMCU_ENTRY_VAL_BIT))
+		return -EFAULT;
+
+	/* Fall back to generic version for cases we're not interested in. */
+	if (pte & MMCU_ENTRY_WRC_BIT	|| /* write combined memory */
+	    (ldst & (size - 1))		|| /* destination unaligned */
+	    size > 8			|| /* more than max write size */
+	    (size & (size - 1)))	   /* non power of 2 size */
+		return __probe_kernel_write(dst, src, size);
+
+	/* If src is unaligned, copy to the aligned bounce buffer first. */
+	if (lsrc & (size - 1)) {
+		for (i = 0; i < size; ++i)
+			bounce[i] = psrc[i];
+		psrc = bounce;
+	}
+
+	switch (size) {
+	case 1:
+		writeb(*psrc, iodst);
+		break;
+	case 2:
+		writew(*(const u16 *)psrc, iodst);
+		break;
+	case 4:
+		writel(*(const u32 *)psrc, iodst);
+		break;
+	case 8:
+		writeq(*(const u64 *)psrc, iodst);
+		break;
+	}
+	return 0;
+}
+#endif

arch/metag/mm/mmu-meta1.c

@@ -0,0 +1,157 @@
+/*
+ *  Copyright (C) 2005,2006,2007,2008,2009 Imagination Technologies
+ *
+ * Meta 1 MMU handling code.
+ *
+ */
+
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/io.h>
+
+#include <asm/mmu.h>
+
+#define DM3_BASE (LINSYSDIRECT_BASE + (MMCU_DIRECTMAPn_ADDR_SCALE * 3))
+
+/*
+ * This contains the physical address of the top level 2k pgd table.
+ */
+static unsigned long mmu_base_phys;
+
+/*
+ * Given a physical address, return a mapped virtual address that can be used
+ * to access that location.
+ * In practice, we use the DirectMap region to make this happen.
+ */
+static unsigned long map_addr(unsigned long phys)
+{
+	static unsigned long dm_base = 0xFFFFFFFF;
+	int offset;
+
+	offset = phys - dm_base;
+
+	/* Are we in the current map range ? */
+	if ((offset < 0) || (offset >= MMCU_DIRECTMAPn_ADDR_SCALE)) {
+		/* Calculate new DM area */
+		dm_base = phys & ~(MMCU_DIRECTMAPn_ADDR_SCALE - 1);
+
+		/* Actually map it in! */
+		metag_out32(dm_base, MMCU_DIRECTMAP3_ADDR);
+
+		/* And calculate how far into that area our reference is */
+		offset = phys - dm_base;
+	}
+
+	return DM3_BASE + offset;
+}
+
+/*
+ * Return the physical address of the base of our pgd table.
+ */
+static inline unsigned long __get_mmu_base(void)
+{
+	unsigned long base_phys;
+	unsigned int stride;
+
+	if (is_global_space(PAGE_OFFSET))
+		stride = 4;
+	else
+		stride = hard_processor_id();	/* [0..3] */
+
+	base_phys = metag_in32(MMCU_TABLE_PHYS_ADDR);
+	base_phys += (0x800 * stride);
+
+	return base_phys;
+}
+
+/* Given a virtual address, return the virtual address of the relevant pgd */
+static unsigned long pgd_entry_addr(unsigned long virt)
+{
+	unsigned long pgd_phys;
+	unsigned long pgd_virt;
+
+	if (!mmu_base_phys)
+		mmu_base_phys = __get_mmu_base();
+
+	/*
+	 * Are we trying to map a global address.  If so, then index
+	 * the global pgd table instead of our local one.
+	 */
+	if (is_global_space(virt)) {
+		/* Scale into 2gig map */
+		virt &= ~0x80000000;
+	}
+
+	/* Base of the pgd table plus our 4Meg entry, 4bytes each */
+	pgd_phys = mmu_base_phys + ((virt >> PGDIR_SHIFT) * 4);
+
+	pgd_virt = map_addr(pgd_phys);
+
+	return pgd_virt;
+}
+
+/* Given a virtual address, return the virtual address of the relevant pte */
+static unsigned long pgtable_entry_addr(unsigned long virt)
+{
+	unsigned long pgtable_phys;
+	unsigned long pgtable_virt, pte_virt;
+
+	/* Find the physical address of the 4MB page table*/
+	pgtable_phys = metag_in32(pgd_entry_addr(virt)) & MMCU_ENTRY_ADDR_BITS;
+
+	/* Map it to a virtual address */
+	pgtable_virt = map_addr(pgtable_phys);
+
+	/* And index into it for our pte */
+	pte_virt = pgtable_virt + ((virt >> PAGE_SHIFT) & 0x3FF) * 4;
+
+	return pte_virt;
+}
+
+unsigned long mmu_read_first_level_page(unsigned long vaddr)
+{
+	return metag_in32(pgd_entry_addr(vaddr));
+}
+
+unsigned long mmu_read_second_level_page(unsigned long vaddr)
+{
+	return metag_in32(pgtable_entry_addr(vaddr));
+}
+
+unsigned long mmu_get_base(void)
+{
+	static unsigned long __base;
+
+	/* Find the base of our MMU pgd table */
+	if (!__base)
+		__base = pgd_entry_addr(0);
+
+	return __base;
+}
+
+void __init mmu_init(unsigned long mem_end)
+{
+	unsigned long entry, addr;
+	pgd_t *p_swapper_pg_dir;
+
+	/*
+	 * Now copy over any MMU pgd entries already in the mmu page tables
+	 * over to our root init process (swapper_pg_dir) map.  This map is
+	 * then inherited by all other processes, which means all processes
+	 * inherit a map of the kernel space.
+	 */
+	addr = PAGE_OFFSET;
+	entry = pgd_index(PAGE_OFFSET);
+	p_swapper_pg_dir = pgd_offset_k(0) + entry;
+
+	while (addr <= META_MEMORY_LIMIT) {
+		unsigned long pgd_entry;
+		/* copy over the current MMU value */
+		pgd_entry = mmu_read_first_level_page(addr);
+		pgd_val(*p_swapper_pg_dir) = pgd_entry;
+
+		p_swapper_pg_dir++;
+		addr += PGDIR_SIZE;
+		entry++;
+	}
+}

arch/metag/mm/mmu-meta2.c

@@ -0,0 +1,207 @@
+/*
+ * Copyright (C) 2008,2009,2010,2011 Imagination Technologies Ltd.
+ *
+ * Meta 2 enhanced mode MMU handling code.
+ *
+ */
+
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <linux/bootmem.h>
+#include <linux/syscore_ops.h>
+
+#include <asm/mmu.h>
+#include <asm/mmu_context.h>
+
+unsigned long mmu_read_first_level_page(unsigned long vaddr)
+{
+	unsigned int cpu = hard_processor_id();
+	unsigned long offset, linear_base, linear_limit;
+	unsigned int phys0;
+	pgd_t *pgd, entry;
+
+	if (is_global_space(vaddr))
+		vaddr &= ~0x80000000;
+
+	offset = vaddr >> PGDIR_SHIFT;
+
+	phys0 = metag_in32(mmu_phys0_addr(cpu));
+
+	/* Top bit of linear base is always zero. */
+	linear_base = (phys0 >> PGDIR_SHIFT) & 0x1ff;
+
+	/* Limit in the range 0 (4MB) to 9 (2GB). */
+	linear_limit = 1 << ((phys0 >> 8) & 0xf);
+	linear_limit += linear_base;
+
+	/*
+	 * If offset is below linear base or above the limit then no
+	 * mapping exists.
+	 */
+	if (offset < linear_base || offset > linear_limit)
+		return 0;
+
+	offset -= linear_base;
+	pgd = (pgd_t *)mmu_get_base();
+	entry = pgd[offset];
+
+	return pgd_val(entry);
+}
+
+unsigned long mmu_read_second_level_page(unsigned long vaddr)
+{
+	return __builtin_meta2_cacherd((void *)(vaddr & PAGE_MASK));
+}
+
+unsigned long mmu_get_base(void)
+{
+	unsigned int cpu = hard_processor_id();
+	unsigned long stride;
+
+	stride = cpu * LINSYSMEMTnX_STRIDE;
+
+	/*
+	 * Bits 18:2 of the MMCU_TnLocal_TABLE_PHYS1 register should be
+	 * used as an offset to the start of the top-level pgd table.
+	 */
+	stride += (metag_in32(mmu_phys1_addr(cpu)) & 0x7fffc);
+
+	if (is_global_space(PAGE_OFFSET))
+		stride += LINSYSMEMTXG_OFFSET;
+
+	return LINSYSMEMT0L_BASE + stride;
+}
+
+#define FIRST_LEVEL_MASK	0xffffffc0
+#define SECOND_LEVEL_MASK	0xfffff000
+#define SECOND_LEVEL_ALIGN	64
+
+static void repriv_mmu_tables(void)
+{
+	unsigned long phys0_addr;
+	unsigned int g;
+
+	/*
+	 * Check that all the mmu table regions are priv protected, and if not
+	 * fix them and emit a warning. If we left them without priv protection
+	 * then userland processes would have access to a 2M window into
+	 * physical memory near where the page tables are.
+	 */
+	phys0_addr = MMCU_T0LOCAL_TABLE_PHYS0;
+	for (g = 0; g < 2; ++g) {
+		unsigned int t, phys0;
+		unsigned long flags;
+		for (t = 0; t < 4; ++t) {
+			__global_lock2(flags);
+			phys0 = metag_in32(phys0_addr);
+			if ((phys0 & _PAGE_PRESENT) && !(phys0 & _PAGE_PRIV)) {
+				pr_warn("Fixing priv protection on T%d %s MMU table region\n",
+					t,
+					g ? "global" : "local");
+				phys0 |= _PAGE_PRIV;
+				metag_out32(phys0, phys0_addr);
+			}
+			__global_unlock2(flags);
+
+			phys0_addr += MMCU_TnX_TABLE_PHYSX_STRIDE;
+		}
+
+		phys0_addr += MMCU_TXG_TABLE_PHYSX_OFFSET
+			    - 4*MMCU_TnX_TABLE_PHYSX_STRIDE;
+	}
+}
+
+#ifdef CONFIG_METAG_SUSPEND_MEM
+static void mmu_resume(void)
+{
+	/*
+	 * If a full suspend to RAM has happened then the original bad MMU table
+	 * priv may have been restored, so repriv them again.
+	 */
+	repriv_mmu_tables();
+}
+#else
+#define mmu_resume NULL
+#endif	/* CONFIG_METAG_SUSPEND_MEM */
+
+static struct syscore_ops mmu_syscore_ops = {
+	.resume  = mmu_resume,
+};
+
+void __init mmu_init(unsigned long mem_end)
+{
+	unsigned long entry, addr;
+	pgd_t *p_swapper_pg_dir;
+#ifdef CONFIG_KERNEL_4M_PAGES
+	unsigned long mem_size = mem_end - PAGE_OFFSET;
+	unsigned int pages = DIV_ROUND_UP(mem_size, 1 << 22);
+	unsigned int second_level_entry = 0;
+	unsigned long *second_level_table;
+#endif
+
+	/*
+	 * Now copy over any MMU pgd entries already in the mmu page tables
+	 * over to our root init process (swapper_pg_dir) map.  This map is
+	 * then inherited by all other processes, which means all processes
+	 * inherit a map of the kernel space.
+	 */
+	addr = META_MEMORY_BASE;
+	entry = pgd_index(META_MEMORY_BASE);
+	p_swapper_pg_dir = pgd_offset_k(0) + entry;
+
+	while (entry < (PTRS_PER_PGD - pgd_index(META_MEMORY_BASE))) {
+		unsigned long pgd_entry;
+		/* copy over the current MMU value */
+		pgd_entry = mmu_read_first_level_page(addr);
+		pgd_val(*p_swapper_pg_dir) = pgd_entry;
+
+		p_swapper_pg_dir++;
+		addr += PGDIR_SIZE;
+		entry++;
+	}
+
+#ifdef CONFIG_KERNEL_4M_PAGES
+	/*
+	 * At this point we can also map the kernel with 4MB pages to
+	 * reduce TLB pressure.
+	 */
+	second_level_table = alloc_bootmem_pages(SECOND_LEVEL_ALIGN * pages);
+
+	addr = PAGE_OFFSET;
+	entry = pgd_index(PAGE_OFFSET);
+	p_swapper_pg_dir = pgd_offset_k(0) + entry;
+
+	while (pages > 0) {
+		unsigned long phys_addr, second_level_phys;
+		pte_t *pte = (pte_t *)&second_level_table[second_level_entry];
+
+		phys_addr = __pa(addr);
+
+		second_level_phys = __pa(pte);
+
+		pgd_val(*p_swapper_pg_dir) = ((second_level_phys &
+					       FIRST_LEVEL_MASK) |
+					      _PAGE_SZ_4M |
+					      _PAGE_PRESENT);
+
+		pte_val(*pte) = ((phys_addr & SECOND_LEVEL_MASK) |
+				 _PAGE_PRESENT | _PAGE_DIRTY |
+				 _PAGE_ACCESSED | _PAGE_WRITE |
+				 _PAGE_CACHEABLE | _PAGE_KERNEL);
+
+		p_swapper_pg_dir++;
+		addr += PGDIR_SIZE;
+		/* Second level pages must be 64byte aligned. */
+		second_level_entry += (SECOND_LEVEL_ALIGN /
+				       sizeof(unsigned long));
+		pages--;
+	}
+	load_pgd(swapper_pg_dir, hard_processor_id());
+	flush_tlb_all();
+#endif
+
+	repriv_mmu_tables();
+	register_syscore_ops(&mmu_syscore_ops);
+}

arch/metag/mm/numa.c

@@ -0,0 +1,81 @@
+/*
+ *  Multiple memory node support for Meta machines
+ *
+ *  Copyright (C) 2007  Paul Mundt
+ *  Copyright (C) 2010  Imagination Technologies Ltd.
+ *
+ * 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/export.h>
+#include <linux/bootmem.h>
+#include <linux/memblock.h>
+#include <linux/mm.h>
+#include <linux/numa.h>
+#include <linux/pfn.h>
+#include <asm/sections.h>
+
+struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
+EXPORT_SYMBOL_GPL(node_data);
+
+extern char _heap_start[];
+
+/*
+ * On Meta machines the conventional approach is to stash system RAM
+ * in node 0, and other memory blocks in to node 1 and up, ordered by
+ * latency. Each node's pgdat is node-local at the beginning of the node,
+ * immediately followed by the node mem map.
+ */
+void __init setup_bootmem_node(int nid, unsigned long start, unsigned long end)
+{
+	unsigned long bootmap_pages, bootmem_paddr;
+	unsigned long start_pfn, end_pfn;
+	unsigned long pgdat_paddr;
+
+	/* Don't allow bogus node assignment */
+	BUG_ON(nid > MAX_NUMNODES || nid <= 0);
+
+	start_pfn = start >> PAGE_SHIFT;
+	end_pfn = end >> PAGE_SHIFT;
+
+	memblock_add(start, end - start);
+
+	memblock_set_node(PFN_PHYS(start_pfn),
+			  PFN_PHYS(end_pfn - start_pfn), nid);
+
+	/* Node-local pgdat */
+	pgdat_paddr = memblock_alloc_base(sizeof(struct pglist_data),
+					  SMP_CACHE_BYTES, end);
+	NODE_DATA(nid) = __va(pgdat_paddr);
+	memset(NODE_DATA(nid), 0, sizeof(struct pglist_data));
+
+	NODE_DATA(nid)->bdata = &bootmem_node_data[nid];
+	NODE_DATA(nid)->node_start_pfn = start_pfn;
+	NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn;
+
+	/* Node-local bootmap */
+	bootmap_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
+	bootmem_paddr = memblock_alloc_base(bootmap_pages << PAGE_SHIFT,
+					    PAGE_SIZE, end);
+	init_bootmem_node(NODE_DATA(nid), bootmem_paddr >> PAGE_SHIFT,
+			  start_pfn, end_pfn);
+
+	free_bootmem_with_active_regions(nid, end_pfn);
+
+	/* Reserve the pgdat and bootmap space with the bootmem allocator */
+	reserve_bootmem_node(NODE_DATA(nid), pgdat_paddr & PAGE_MASK,
+			     sizeof(struct pglist_data), BOOTMEM_DEFAULT);
+	reserve_bootmem_node(NODE_DATA(nid), bootmem_paddr,
+			     bootmap_pages << PAGE_SHIFT, BOOTMEM_DEFAULT);
+
+	/* It's up */
+	node_set_online(nid);
+
+	/* Kick sparsemem */
+	sparse_memory_present_with_active_regions(nid);
+}
+
+void __init __weak soc_mem_setup(void)
+{
+}