Merge tag 'xtensa-for-next-20140406' of git://github.com/jcmvbkbc/linux-xtensa into for_next

Merging from Max' tree.

Xtensa fixes for 3.15:
- add missing cache manipulation symbol exports to fix build failures;
- sort extable at build time;
- clean up sysmem code, support memmap boot parameter;
- add highmem support for cores with non-aliasing caches;
- add DTS for xtfpga on KC705.

Signed-off-by: Chris Zankel <chris@zankel.net>

21 files changed, 688 insertions, 154 deletions

diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index c87ae7c..17b3198 100644
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -14,6 +14,7 @@ config XTENSA
 	select GENERIC_PCI_IOMAP
 	select ARCH_WANT_IPC_PARSE_VERSION
 	select ARCH_WANT_OPTIONAL_GPIOLIB
+	select BUILDTIME_EXTABLE_SORT
 	select CLONE_BACKWARDS
 	select IRQ_DOMAIN
 	select HAVE_OPROFILE
@@ -189,6 +190,24 @@ config INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
 
 	  If in doubt, say Y.
 
+config HIGHMEM
+	bool "High Memory Support"
+	help
+	  Linux can use the full amount of RAM in the system by
+	  default. However, the default MMUv2 setup only maps the
+	  lowermost 128 MB of memory linearly to the areas starting
+	  at 0xd0000000 (cached) and 0xd8000000 (uncached).
+	  When there are more than 128 MB memory in the system not
+	  all of it can be "permanently mapped" by the kernel.
+	  The physical memory that's not permanently mapped is called
+	  "high memory".
+
+	  If you are compiling a kernel which will never run on a
+	  machine with more than 128 MB total physical RAM, answer
+	  N here.
+
+	  If unsure, say Y.
+
 endmenu
 
 config XTENSA_CALIBRATE_CCOUNT
diff --git a/arch/xtensa/boot/dts/kc705.dts b/arch/xtensa/boot/dts/kc705.dts
new file mode 100644
index 0000000..742a347
--- /dev/null
+++ b/arch/xtensa/boot/dts/kc705.dts
@@ -0,0 +1,11 @@
+/dts-v1/;
+/include/ "xtfpga.dtsi"
+/include/ "xtfpga-flash-128m.dtsi"
+
+/ {
+	compatible = "cdns,xtensa-kc705";
+	memory@0 {
+		device_type = "memory";
+		reg = <0x00000000 0x08000000>;
+	};
+};
diff --git a/arch/xtensa/boot/dts/xtfpga-flash-128m.dtsi b/arch/xtensa/boot/dts/xtfpga-flash-128m.dtsi
new file mode 100644
index 0000000..d3a88e0
--- /dev/null
+++ b/arch/xtensa/boot/dts/xtfpga-flash-128m.dtsi
@@ -0,0 +1,28 @@
+/ {
+	soc {
+		flash: flash@00000000 {
+			#address-cells = <1>;
+			#size-cells = <1>;
+			compatible = "cfi-flash";
+			reg = <0x00000000 0x08000000>;
+			bank-width = <2>;
+			device-width = <2>;
+			partition@0x0 {
+				label = "data";
+				reg = <0x00000000 0x06000000>;
+			};
+			partition@0x6000000 {
+				label = "boot loader area";
+				reg = <0x06000000 0x00800000>;
+			};
+			partition@0x6800000 {
+				label = "kernel image";
+				reg = <0x06800000 0x017e0000>;
+			};
+			partition@0x7fe0000 {
+				label = "boot environment";
+				reg = <0x07fe0000 0x00020000>;
+			};
+		};
+        };
+};
diff --git a/arch/xtensa/boot/dts/xtfpga-flash-16m.dtsi b/arch/xtensa/boot/dts/xtfpga-flash-16m.dtsi
index e5703c7..1d97203 100644
--- a/arch/xtensa/boot/dts/xtfpga-flash-16m.dtsi
+++ b/arch/xtensa/boot/dts/xtfpga-flash-16m.dtsi
@@ -1,26 +1,28 @@
 / {
-	flash: flash@f8000000 {
-		#address-cells = <1>;
-		#size-cells = <1>;
-		compatible = "cfi-flash";
-		reg = <0xf8000000 0x01000000>;
-		bank-width = <2>;
-		device-width = <2>;
-		partition@0x0 {
-			label = "boot loader area";
-			reg = <0x00000000 0x00400000>;
+	soc {
+		flash: flash@08000000 {
+			#address-cells = <1>;
+			#size-cells = <1>;
+			compatible = "cfi-flash";
+			reg = <0x08000000 0x01000000>;
+			bank-width = <2>;
+			device-width = <2>;
+			partition@0x0 {
+				label = "boot loader area";
+				reg = <0x00000000 0x00400000>;
+			};
+			partition@0x400000 {
+				label = "kernel image";
+				reg = <0x00400000 0x00600000>;
+			};
+			partition@0xa00000 {
+				label = "data";
+				reg = <0x00a00000 0x005e0000>;
+			};
+			partition@0xfe0000 {
+				label = "boot environment";
+				reg = <0x00fe0000 0x00020000>;
+			};
 		};
-		partition@0x400000 {
-			label = "kernel image";
-			reg = <0x00400000 0x00600000>;
-		};
-		partition@0xa00000 {
-			label = "data";
-			reg = <0x00a00000 0x005e0000>;
-		};
-		partition@0xfe0000 {
-			label = "boot environment";
-			reg = <0x00fe0000 0x00020000>;
-		};
-        };
+	};
 };
diff --git a/arch/xtensa/boot/dts/xtfpga-flash-4m.dtsi b/arch/xtensa/boot/dts/xtfpga-flash-4m.dtsi
index 6f9c10d..d1c621c 100644
--- a/arch/xtensa/boot/dts/xtfpga-flash-4m.dtsi
+++ b/arch/xtensa/boot/dts/xtfpga-flash-4m.dtsi
@@ -1,18 +1,20 @@
 / {
-	flash: flash@f8000000 {
-		#address-cells = <1>;
-		#size-cells = <1>;
-		compatible = "cfi-flash";
-		reg = <0xf8000000 0x00400000>;
-		bank-width = <2>;
-		device-width = <2>;
-		partition@0x0 {
-			label = "boot loader area";
-			reg = <0x00000000 0x003f0000>;
+	soc {
+		flash: flash@08000000 {
+			#address-cells = <1>;
+			#size-cells = <1>;
+			compatible = "cfi-flash";
+			reg = <0x08000000 0x00400000>;
+			bank-width = <2>;
+			device-width = <2>;
+			partition@0x0 {
+				label = "boot loader area";
+				reg = <0x00000000 0x003f0000>;
+			};
+			partition@0x3f0000 {
+				label = "boot environment";
+				reg = <0x003f0000 0x00010000>;
+			};
 		};
-		partition@0x3f0000 {
-			label = "boot environment";
-			reg = <0x003f0000 0x00010000>;
-		};
-        };
+	};
 };
diff --git a/arch/xtensa/boot/dts/xtfpga.dtsi b/arch/xtensa/boot/dts/xtfpga.dtsi
index e7370b1..dec9178 100644
--- a/arch/xtensa/boot/dts/xtfpga.dtsi
+++ b/arch/xtensa/boot/dts/xtfpga.dtsi
@@ -42,21 +42,28 @@
 		};
 	};
 
-	serial0: serial@fd050020 {
-		device_type = "serial";
-		compatible = "ns16550a";
-		no-loopback-test;
-		reg = <0xfd050020 0x20>;
-		reg-shift = <2>;
-		interrupts = <0 1>; /* external irq 0 */
-		clocks = <&osc>;
-	};
+	soc {
+		#address-cells = <1>;
+		#size-cells = <1>;
+		compatible = "simple-bus";
+		ranges = <0x00000000 0xf0000000 0x10000000>;
 
-	enet0: ethoc@fd030000 {
-		compatible = "opencores,ethoc";
-		reg = <0xfd030000 0x4000 0xfd800000 0x4000>;
-		interrupts = <1 1>; /* external irq 1 */
-		local-mac-address = [00 50 c2 13 6f 00];
-		clocks = <&osc>;
+		serial0: serial@0d050020 {
+			device_type = "serial";
+			compatible = "ns16550a";
+			no-loopback-test;
+			reg = <0x0d050020 0x20>;
+			reg-shift = <2>;
+			interrupts = <0 1>; /* external irq 0 */
+			clocks = <&osc>;
+		};
+
+		enet0: ethoc@0d030000 {
+			compatible = "opencores,ethoc";
+			reg = <0x0d030000 0x4000 0x0d800000 0x4000>;
+			interrupts = <1 1>; /* external irq 1 */
+			local-mac-address = [00 50 c2 13 6f 00];
+			clocks = <&osc>;
+		};
 	};
 };
diff --git a/arch/xtensa/include/asm/bootparam.h b/arch/xtensa/include/asm/bootparam.h
index 23392c5..892aab3 100644
--- a/arch/xtensa/include/asm/bootparam.h
+++ b/arch/xtensa/include/asm/bootparam.h
@@ -37,23 +37,14 @@ typedef struct bp_tag {
 	unsigned long data[0];	/* data */
 } bp_tag_t;
 
-typedef struct meminfo {
+struct bp_meminfo {
 	unsigned long type;
 	unsigned long start;
 	unsigned long end;
-} meminfo_t;
-
-#define SYSMEM_BANKS_MAX 5
+};
 
 #define MEMORY_TYPE_CONVENTIONAL	0x1000
 #define MEMORY_TYPE_NONE		0x2000
 
-typedef struct sysmem_info {
-	int nr_banks;
-	meminfo_t bank[SYSMEM_BANKS_MAX];
-} sysmem_info_t;
-
-extern sysmem_info_t sysmem;
-
 #endif
 #endif
diff --git a/arch/xtensa/include/asm/fixmap.h b/arch/xtensa/include/asm/fixmap.h
new file mode 100644
index 0000000..9f6c33d0
--- /dev/null
+++ b/arch/xtensa/include/asm/fixmap.h
@@ -0,0 +1,58 @@
+/*
+ * fixmap.h: compile-time virtual memory allocation
+ *
+ * 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.
+ *
+ * Copyright (C) 1998 Ingo Molnar
+ *
+ * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
+ */
+
+#ifndef _ASM_FIXMAP_H
+#define _ASM_FIXMAP_H
+
+#include <asm/pgtable.h>
+#ifdef CONFIG_HIGHMEM
+#include <linux/threads.h>
+#include <asm/kmap_types.h>
+#endif
+
+/*
+ * Here we define all the compile-time 'special' virtual
+ * addresses. The point is to have a constant address at
+ * compile time, but to set the physical address only
+ * in the boot process. We allocate these special  addresses
+ * from the end of the consistent memory region backwards.
+ * Also this lets us do fail-safe vmalloc(), we
+ * can guarantee that these special addresses and
+ * vmalloc()-ed addresses never overlap.
+ *
+ * these 'compile-time allocated' memory buffers are
+ * fixed-size 4k pages. (or larger if used with an increment
+ * higher than 1) use fixmap_set(idx,phys) to associate
+ * physical memory with fixmap indices.
+ */
+enum fixed_addresses {
+#ifdef CONFIG_HIGHMEM
+	/* reserved pte's for temporary kernel mappings */
+	FIX_KMAP_BEGIN,
+	FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS) - 1,
+#endif
+	__end_of_fixed_addresses
+};
+
+#define FIXADDR_TOP     (VMALLOC_START - PAGE_SIZE)
+#define FIXADDR_SIZE	(__end_of_fixed_addresses << PAGE_SHIFT)
+#define FIXADDR_START	((FIXADDR_TOP - FIXADDR_SIZE) & PMD_MASK)
+
+#include <asm-generic/fixmap.h>
+
+#define kmap_get_fixmap_pte(vaddr) \
+	pte_offset_kernel( \
+		pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr)), \
+		(vaddr) \
+	)
+
+#endif
diff --git a/arch/xtensa/include/asm/highmem.h b/arch/xtensa/include/asm/highmem.h
index 80be151..2653ef5 100644
--- a/arch/xtensa/include/asm/highmem.h
+++ b/arch/xtensa/include/asm/highmem.h
@@ -6,11 +6,54 @@
  * this archive for more details.
  *
  * Copyright (C) 2003 - 2005 Tensilica Inc.
+ * Copyright (C) 2014 Cadence Design Systems Inc.
  */
 
 #ifndef _XTENSA_HIGHMEM_H
 #define _XTENSA_HIGHMEM_H
 
-extern void flush_cache_kmaps(void);
+#include <asm/cacheflush.h>
+#include <asm/fixmap.h>
+#include <asm/kmap_types.h>
+#include <asm/pgtable.h>
+
+#define PKMAP_BASE		(FIXADDR_START - PMD_SIZE)
+#define LAST_PKMAP		PTRS_PER_PTE
+#define LAST_PKMAP_MASK		(LAST_PKMAP - 1)
+#define PKMAP_NR(virt)		(((virt) - PKMAP_BASE) >> PAGE_SHIFT)
+#define PKMAP_ADDR(nr)		(PKMAP_BASE + ((nr) << PAGE_SHIFT))
+
+#define kmap_prot		PAGE_KERNEL
+
+extern pte_t *pkmap_page_table;
+
+void *kmap_high(struct page *page);
+void kunmap_high(struct page *page);
+
+static inline void *kmap(struct page *page)
+{
+	BUG_ON(in_interrupt());
+	if (!PageHighMem(page))
+		return page_address(page);
+	return kmap_high(page);
+}
+
+static inline void kunmap(struct page *page)
+{
+	BUG_ON(in_interrupt());
+	if (!PageHighMem(page))
+		return;
+	kunmap_high(page);
+}
+
+static inline void flush_cache_kmaps(void)
+{
+	flush_cache_all();
+}
+
+void *kmap_atomic(struct page *page);
+void __kunmap_atomic(void *kvaddr);
+
+void kmap_init(void);
 
 #endif
diff --git a/arch/xtensa/include/asm/pgtable.h b/arch/xtensa/include/asm/pgtable.h
index 2164462..4b0ca35 100644
--- a/arch/xtensa/include/asm/pgtable.h
+++ b/arch/xtensa/include/asm/pgtable.h
@@ -310,6 +310,10 @@ set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t pteval)
 	update_pte(ptep, pteval);
 }
 
+static inline void set_pte(pte_t *ptep, pte_t pteval)
+{
+	update_pte(ptep, pteval);
+}
 
 static inline void
 set_pmd(pmd_t *pmdp, pmd_t pmdval)
diff --git a/arch/xtensa/include/asm/sysmem.h b/arch/xtensa/include/asm/sysmem.h
new file mode 100644
index 0000000..c015c5c
--- /dev/null
+++ b/arch/xtensa/include/asm/sysmem.h
@@ -0,0 +1,38 @@
+/*
+ * sysmem-related prototypes.
+ *
+ * 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.
+ *
+ * Copyright (C) 2014 Cadence Design Systems Inc.
+ */
+
+#ifndef _XTENSA_SYSMEM_H
+#define _XTENSA_SYSMEM_H
+
+#define SYSMEM_BANKS_MAX 31
+
+struct meminfo {
+	unsigned long start;
+	unsigned long end;
+};
+
+/*
+ * Bank array is sorted by .start.
+ * Banks don't overlap and there's at least one page gap
+ * between adjacent bank entries.
+ */
+struct sysmem_info {
+	int nr_banks;
+	struct meminfo bank[SYSMEM_BANKS_MAX];
+};
+
+extern struct sysmem_info sysmem;
+
+int add_sysmem_bank(unsigned long start, unsigned long end);
+int mem_reserve(unsigned long, unsigned long, int);
+void bootmem_init(void);
+void zones_init(void);
+
+#endif /* _XTENSA_SYSMEM_H */
diff --git a/arch/xtensa/include/asm/tlbflush.h b/arch/xtensa/include/asm/tlbflush.h
index fc34274..06875feb 100644
--- a/arch/xtensa/include/asm/tlbflush.h
+++ b/arch/xtensa/include/asm/tlbflush.h
@@ -36,6 +36,7 @@ void local_flush_tlb_page(struct vm_area_struct *vma,
 		unsigned long page);
 void local_flush_tlb_range(struct vm_area_struct *vma,
 		unsigned long start, unsigned long end);
+void local_flush_tlb_kernel_range(unsigned long start, unsigned long end);
 
 #ifdef CONFIG_SMP
 
@@ -44,12 +45,7 @@ void flush_tlb_mm(struct mm_struct *);
 void flush_tlb_page(struct vm_area_struct *, unsigned long);
 void flush_tlb_range(struct vm_area_struct *, unsigned long,
 		unsigned long);
-
-static inline void flush_tlb_kernel_range(unsigned long start,
-		unsigned long end)
-{
-	flush_tlb_all();
-}
+void flush_tlb_kernel_range(unsigned long start, unsigned long end);
 
 #else /* !CONFIG_SMP */
 
@@ -58,7 +54,8 @@ static inline void flush_tlb_kernel_range(unsigned long start,
 #define flush_tlb_page(vma, page)	   local_flush_tlb_page(vma, page)
 #define flush_tlb_range(vma, vmaddr, end)  local_flush_tlb_range(vma, vmaddr, \
 								 end)
-#define flush_tlb_kernel_range(start, end) local_flush_tlb_all()
+#define flush_tlb_kernel_range(start, end) local_flush_tlb_kernel_range(start, \
+									end)
 
 #endif /* CONFIG_SMP */
 
diff --git a/arch/xtensa/kernel/setup.c b/arch/xtensa/kernel/setup.c
index 84fe931..9757bb7 100644
--- a/arch/xtensa/kernel/setup.c
+++ b/arch/xtensa/kernel/setup.c
@@ -50,6 +50,7 @@
 #include <asm/param.h>
 #include <asm/traps.h>
 #include <asm/smp.h>
+#include <asm/sysmem.h>
 
 #include <platform/hardware.h>
 
@@ -88,12 +89,6 @@ static char __initdata command_line[COMMAND_LINE_SIZE];
 static char default_command_line[COMMAND_LINE_SIZE] __initdata = CONFIG_CMDLINE;
 #endif
 
-sysmem_info_t __initdata sysmem;
-
-extern int mem_reserve(unsigned long, unsigned long, int);
-extern void bootmem_init(void);
-extern void zones_init(void);
-
 /*
  * Boot parameter parsing.
  *
@@ -113,31 +108,14 @@ typedef struct tagtable {
 
 /* parse current tag */
 
-static int __init add_sysmem_bank(unsigned long type, unsigned long start,
-		unsigned long end)
-{
-	if (sysmem.nr_banks >= SYSMEM_BANKS_MAX) {
-		printk(KERN_WARNING
-				"Ignoring memory bank 0x%08lx size %ldKB\n",
-				start, end - start);
-		return -EINVAL;
-	}
-	sysmem.bank[sysmem.nr_banks].type  = type;
-	sysmem.bank[sysmem.nr_banks].start = PAGE_ALIGN(start);
-	sysmem.bank[sysmem.nr_banks].end   = end & PAGE_MASK;
-	sysmem.nr_banks++;
-
-	return 0;
-}
-
 static int __init parse_tag_mem(const bp_tag_t *tag)
 {
-	meminfo_t *mi = (meminfo_t *)(tag->data);
+	struct bp_meminfo *mi = (struct bp_meminfo *)(tag->data);
 
 	if (mi->type != MEMORY_TYPE_CONVENTIONAL)
 		return -1;
 
-	return add_sysmem_bank(mi->type, mi->start, mi->end);
+	return add_sysmem_bank(mi->start, mi->end);
 }
 
 __tagtable(BP_TAG_MEMORY, parse_tag_mem);
@@ -146,8 +124,8 @@ __tagtable(BP_TAG_MEMORY, parse_tag_mem);
 
 static int __init parse_tag_initrd(const bp_tag_t* tag)
 {
-	meminfo_t* mi;
-	mi = (meminfo_t*)(tag->data);
+	struct bp_meminfo *mi = (struct bp_meminfo *)(tag->data);
+
 	initrd_start = (unsigned long)__va(mi->start);
 	initrd_end = (unsigned long)__va(mi->end);
 
@@ -255,7 +233,7 @@ void __init early_init_dt_add_memory_arch(u64 base, u64 size)
 		return;
 
 	size &= PAGE_MASK;
-	add_sysmem_bank(MEMORY_TYPE_CONVENTIONAL, base, base + size);
+	add_sysmem_bank(base, base + size);
 }
 
 void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
@@ -292,8 +270,6 @@ device_initcall(xtensa_device_probe);
 
 void __init init_arch(bp_tag_t *bp_start)
 {
-	sysmem.nr_banks = 0;
-
 	/* Parse boot parameters */
 
 	if (bp_start)
@@ -304,10 +280,9 @@ void __init init_arch(bp_tag_t *bp_start)
 #endif
 
 	if (sysmem.nr_banks == 0) {
-		sysmem.nr_banks = 1;
-		sysmem.bank[0].start = PLATFORM_DEFAULT_MEM_START;
-		sysmem.bank[0].end = PLATFORM_DEFAULT_MEM_START
-				     + PLATFORM_DEFAULT_MEM_SIZE;
+		add_sysmem_bank(PLATFORM_DEFAULT_MEM_START,
+				PLATFORM_DEFAULT_MEM_START +
+				PLATFORM_DEFAULT_MEM_SIZE);
 	}
 
 #ifdef CONFIG_CMDLINE_BOOL
@@ -487,7 +462,7 @@ void __init setup_arch(char **cmdline_p)
 #ifdef CONFIG_BLK_DEV_INITRD
 	if (initrd_start < initrd_end) {
 		initrd_is_mapped = mem_reserve(__pa(initrd_start),
-					       __pa(initrd_end), 0);
+					       __pa(initrd_end), 0) == 0;
 		initrd_below_start_ok = 1;
 	} else {
 		initrd_start = 0;
@@ -532,6 +507,7 @@ void __init setup_arch(char **cmdline_p)
 		    __pa(&_Level6InterruptVector_text_end), 0);
 #endif
 
+	parse_early_param();
 	bootmem_init();
 
 	unflatten_and_copy_device_tree();
diff --git a/arch/xtensa/kernel/smp.c b/arch/xtensa/kernel/smp.c
index aa8bd87..40b5a37 100644
--- a/arch/xtensa/kernel/smp.c
+++ b/arch/xtensa/kernel/smp.c
@@ -496,6 +496,21 @@ void flush_tlb_range(struct vm_area_struct *vma,
 	on_each_cpu(ipi_flush_tlb_range, &fd, 1);
 }
 
+static void ipi_flush_tlb_kernel_range(void *arg)
+{
+	struct flush_data *fd = arg;
+	local_flush_tlb_kernel_range(fd->addr1, fd->addr2);
+}
+
+void flush_tlb_kernel_range(unsigned long start, unsigned long end)
+{
+	struct flush_data fd = {
+		.addr1 = start,
+		.addr2 = end,
+	};
+	on_each_cpu(ipi_flush_tlb_kernel_range, &fd, 1);
+}
+
 /* Cache flush functions */
 
 static void ipi_flush_cache_all(void *arg)
diff --git a/arch/xtensa/kernel/xtensa_ksyms.c b/arch/xtensa/kernel/xtensa_ksyms.c
index 80b33ed..4d2872f 100644
--- a/arch/xtensa/kernel/xtensa_ksyms.c
+++ b/arch/xtensa/kernel/xtensa_ksyms.c
@@ -20,6 +20,7 @@
 #include <linux/in6.h>
 
 #include <asm/uaccess.h>
+#include <asm/cacheflush.h>
 #include <asm/checksum.h>
 #include <asm/dma.h>
 #include <asm/io.h>
@@ -105,6 +106,7 @@ EXPORT_SYMBOL(csum_partial_copy_generic);
  * Architecture-specific symbols
  */
 EXPORT_SYMBOL(__xtensa_copy_user);
+EXPORT_SYMBOL(__invalidate_icache_range);
 
 /*
  * Kernel hacking ...
@@ -127,3 +129,8 @@ EXPORT_SYMBOL(common_exception_return);
 #ifdef CONFIG_FUNCTION_TRACER
 EXPORT_SYMBOL(_mcount);
 #endif
+
+EXPORT_SYMBOL(__invalidate_dcache_range);
+#if XCHAL_DCACHE_IS_WRITEBACK
+EXPORT_SYMBOL(__flush_dcache_range);
+#endif
diff --git a/arch/xtensa/mm/Makefile b/arch/xtensa/mm/Makefile
index f0b646d..f54f78e 100644
--- a/arch/xtensa/mm/Makefile
+++ b/arch/xtensa/mm/Makefile
@@ -4,3 +4,4 @@
 
 obj-y			:= init.o cache.o misc.o
 obj-$(CONFIG_MMU)	+= fault.o mmu.o tlb.o
+obj-$(CONFIG_HIGHMEM)	+= highmem.o
diff --git a/arch/xtensa/mm/cache.c b/arch/xtensa/mm/cache.c
index ba4c47f..63cbb86 100644
--- a/arch/xtensa/mm/cache.c
+++ b/arch/xtensa/mm/cache.c
@@ -59,6 +59,10 @@
  *
  */
 
+#if (DCACHE_WAY_SIZE > PAGE_SIZE) && defined(CONFIG_HIGHMEM)
+#error "HIGHMEM is not supported on cores with aliasing cache."
+#endif
+
 #if (DCACHE_WAY_SIZE > PAGE_SIZE) && XCHAL_DCACHE_IS_WRITEBACK
 
 /*
@@ -179,10 +183,11 @@ update_mmu_cache(struct vm_area_struct * vma, unsigned long addr, pte_t *ptep)
 #else
 	if (!PageReserved(page) && !test_bit(PG_arch_1, &page->flags)
 	    && (vma->vm_flags & VM_EXEC) != 0) {
-	    	unsigned long paddr = (unsigned long) page_address(page);
+		unsigned long paddr = (unsigned long)kmap_atomic(page);
 		__flush_dcache_page(paddr);
 		__invalidate_icache_page(paddr);
 		set_bit(PG_arch_1, &page->flags);
+		kunmap_atomic((void *)paddr);
 	}
 #endif
 }
diff --git a/arch/xtensa/mm/highmem.c b/arch/xtensa/mm/highmem.c
new file mode 100644
index 0000000..17a8c0d
--- /dev/null
+++ b/arch/xtensa/mm/highmem.c
@@ -0,0 +1,72 @@
+/*
+ * High memory support for Xtensa architecture
+ *
+ * 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.
+ *
+ * Copyright (C) 2014 Cadence Design Systems Inc.
+ */
+
+#include <linux/export.h>
+#include <linux/highmem.h>
+#include <asm/tlbflush.h>
+
+static pte_t *kmap_pte;
+
+void *kmap_atomic(struct page *page)
+{
+	enum fixed_addresses idx;
+	unsigned long vaddr;
+	int type;
+
+	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_EXEC));
+
+	return (void *)vaddr;
+}
+EXPORT_SYMBOL(kmap_atomic);
+
+void __kunmap_atomic(void *kvaddr)
+{
+	int idx, type;
+
+	if (kvaddr >= (void *)FIXADDR_START &&
+	    kvaddr < (void *)FIXADDR_TOP) {
+		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, kvaddr, kmap_pte - idx);
+		local_flush_tlb_kernel_range((unsigned long)kvaddr,
+					     (unsigned long)kvaddr + PAGE_SIZE);
+
+		kmap_atomic_idx_pop();
+	}
+
+	pagefault_enable();
+}
+EXPORT_SYMBOL(__kunmap_atomic);
+
+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);
+}
diff --git a/arch/xtensa/mm/init.c b/arch/xtensa/mm/init.c
index aff108d..4224256 100644
--- a/arch/xtensa/mm/init.c
+++ b/arch/xtensa/mm/init.c
@@ -8,6 +8,7 @@
  * for more details.
  *
  * Copyright (C) 2001 - 2005 Tensilica Inc.
+ * Copyright (C) 2014 Cadence Design Systems Inc.
  *
  * Chris Zankel	<chris@zankel.net>
  * Joe Taylor	<joe@tensilica.com, joetylr@yahoo.com>
@@ -19,6 +20,7 @@
 #include <linux/errno.h>
 #include <linux/bootmem.h>
 #include <linux/gfp.h>
+#include <linux/highmem.h>
 #include <linux/swap.h>
 #include <linux/mman.h>
 #include <linux/nodemask.h>
@@ -27,11 +29,133 @@
 #include <asm/bootparam.h>
 #include <asm/page.h>
 #include <asm/sections.h>
+#include <asm/sysmem.h>
+
+struct sysmem_info sysmem __initdata;
+
+static void __init sysmem_dump(void)
+{
+	unsigned i;
+
+	pr_debug("Sysmem:\n");
+	for (i = 0; i < sysmem.nr_banks; ++i)
+		pr_debug("  0x%08lx - 0x%08lx (%ldK)\n",
+			 sysmem.bank[i].start, sysmem.bank[i].end,
+			 (sysmem.bank[i].end - sysmem.bank[i].start) >> 10);
+}
+
+/*
+ * Find bank with maximal .start such that bank.start <= start
+ */
+static inline struct meminfo * __init find_bank(unsigned long start)
+{
+	unsigned i;
+	struct meminfo *it = NULL;
+
+	for (i = 0; i < sysmem.nr_banks; ++i)
+		if (sysmem.bank[i].start <= start)
+			it = sysmem.bank + i;
+		else
+			break;
+	return it;
+}
+
+/*
+ * Move all memory banks starting at 'from' to a new place at 'to',
+ * adjust nr_banks accordingly.
+ * Both 'from' and 'to' must be inside the sysmem.bank.
+ *
+ * Returns: 0 (success), -ENOMEM (not enough space in the sysmem.bank).
+ */
+static int __init move_banks(struct meminfo *to, struct meminfo *from)
+{
+	unsigned n = sysmem.nr_banks - (from - sysmem.bank);
+
+	if (to > from && to - from + sysmem.nr_banks > SYSMEM_BANKS_MAX)
+		return -ENOMEM;
+	if (to != from)
+		memmove(to, from, n * sizeof(struct meminfo));
+	sysmem.nr_banks += to - from;
+	return 0;
+}
+
+/*
+ * Add new bank to sysmem. Resulting sysmem is the union of bytes of the
+ * original sysmem and the new bank.
+ *
+ * Returns: 0 (success), < 0 (error)
+ */
+int __init add_sysmem_bank(unsigned long start, unsigned long end)
+{
+	unsigned i;
+	struct meminfo *it = NULL;
+	unsigned long sz;
+	unsigned long bank_sz = 0;
+
+	if (start == end ||
+	    (start < end) != (PAGE_ALIGN(start) < (end & PAGE_MASK))) {
+		pr_warn("Ignoring small memory bank 0x%08lx size: %ld bytes\n",
+			start, end - start);
+		return -EINVAL;
+	}
+
+	start = PAGE_ALIGN(start);
+	end &= PAGE_MASK;
+	sz = end - start;
+
+	it = find_bank(start);
+
+	if (it)
+		bank_sz = it->end - it->start;
+
+	if (it && bank_sz >= start - it->start) {
+		if (end - it->start > bank_sz)
+			it->end = end;
+		else
+			return 0;
+	} else {
+		if (!it)
+			it = sysmem.bank;
+		else
+			++it;
+
+		if (it - sysmem.bank < sysmem.nr_banks &&
+		    it->start - start <= sz) {
+			it->start = start;
+			if (it->end - it->start < sz)
+				it->end = end;
+			else
+				return 0;
+		} else {
+			if (move_banks(it + 1, it) < 0) {
+				pr_warn("Ignoring memory bank 0x%08lx size %ld bytes\n",
+					start, end - start);
+				return -EINVAL;
+			}
+			it->start = start;
+			it->end = end;
+			return 0;
+		}
+	}
+	sz = it->end - it->start;
+	for (i = it + 1 - sysmem.bank; i < sysmem.nr_banks; ++i)
+		if (sysmem.bank[i].start - it->start <= sz) {
+			if (sz < sysmem.bank[i].end - it->start)
+				it->end = sysmem.bank[i].end;
+		} else {
+			break;
+		}
+
+	move_banks(it + 1, sysmem.bank + i);
+	return 0;
+}
 
 /*
  * mem_reserve(start, end, must_exist)
  *
  * Reserve some memory from the memory pool.
+ * If must_exist is set and a part of the region being reserved does not exist
+ * memory map is not altered.
  *
  * Parameters:
  *  start	Start of region,
@@ -39,53 +163,69 @@
  *  must_exist	Must exist in memory pool.
  *
  * Returns:
- *  0 (memory area couldn't be mapped)
- * -1 (success)
+ *  0 (success)
+ *  < 0 (error)
  */
 
 int __init mem_reserve(unsigned long start, unsigned long end, int must_exist)
 {
-	int i;
-
-	if (start == end)
-		return 0;
+	struct meminfo *it;
+	struct meminfo *rm = NULL;
+	unsigned long sz;
+	unsigned long bank_sz = 0;
 
 	start = start & PAGE_MASK;
 	end = PAGE_ALIGN(end);
+	sz = end - start;
+	if (!sz)
+		return -EINVAL;
 
-	for (i = 0; i < sysmem.nr_banks; i++)
-		if (start < sysmem.bank[i].end
-		    && end >= sysmem.bank[i].start)
-			break;
+	it = find_bank(start);
+
+	if (it)
+		bank_sz = it->end - it->start;
 
-	if (i == sysmem.nr_banks) {
-		if (must_exist)
-			printk (KERN_WARNING "mem_reserve: [0x%0lx, 0x%0lx) "
-				"not in any region!\n", start, end);
-		return 0;
+	if ((!it || end - it->start > bank_sz) && must_exist) {
+		pr_warn("mem_reserve: [0x%0lx, 0x%0lx) not in any region!\n",
+			start, end);
+		return -EINVAL;
 	}
 
-	if (start > sysmem.bank[i].start) {
-		if (end < sysmem.bank[i].end) {
-			/* split entry */
-			if (sysmem.nr_banks >= SYSMEM_BANKS_MAX)
-				panic("meminfo overflow\n");
-			sysmem.bank[sysmem.nr_banks].start = end;
-			sysmem.bank[sysmem.nr_banks].end = sysmem.bank[i].end;
-			sysmem.nr_banks++;
+	if (it && start - it->start < bank_sz) {
+		if (start == it->start) {
+			if (end - it->start < bank_sz) {
+				it->start = end;
+				return 0;
+			} else {
+				rm = it;
+			}
+		} else {
+			it->end = start;
+			if (end - it->start < bank_sz)
+				return add_sysmem_bank(end,
+						       it->start + bank_sz);
+			++it;
 		}
-		sysmem.bank[i].end = start;
+	}
 
-	} else if (end < sysmem.bank[i].end) {
-		sysmem.bank[i].start = end;
+	if (!it)
+		it = sysmem.bank;
 
-	} else {
-		/* remove entry */
-		sysmem.nr_banks--;
-		sysmem.bank[i].start = sysmem.bank[sysmem.nr_banks].start;
-		sysmem.bank[i].end   = sysmem.bank[sysmem.nr_banks].end;
+	for (; it < sysmem.bank + sysmem.nr_banks; ++it) {
+		if (it->end - start <= sz) {
+			if (!rm)
+				rm = it;
+		} else {
+			if (it->start - start < sz)
+				it->start = end;
+			break;
+		}
 	}
-	return -1;
+
+	if (rm)
+		move_banks(rm, it);
+
+	return 0;
 }
 
 
@@ -99,6 +239,7 @@ void __init bootmem_init(void)
 	unsigned long bootmap_start, bootmap_size;
 	int i;
 
+	sysmem_dump();
 	max_low_pfn = max_pfn = 0;
 	min_low_pfn = ~0;
 
@@ -156,19 +297,13 @@ void __init bootmem_init(void)
 
 void __init zones_init(void)
 {
-	unsigned long zones_size[MAX_NR_ZONES];
-	int i;
-
 	/* All pages are DMA-able, so we put them all in the DMA zone. */
-
-	zones_size[ZONE_DMA] = max_low_pfn - ARCH_PFN_OFFSET;
-	for (i = 1; i < MAX_NR_ZONES; i++)
-		zones_size[i] = 0;
-
+	unsigned long zones_size[MAX_NR_ZONES] = {
+		[ZONE_DMA] = max_low_pfn - ARCH_PFN_OFFSET,
 #ifdef CONFIG_HIGHMEM
-	zones_size[ZONE_HIGHMEM] = max_pfn - max_low_pfn;
+		[ZONE_HIGHMEM] = max_pfn - max_low_pfn,
 #endif
-
+	};
 	free_area_init_node(0, zones_size, ARCH_PFN_OFFSET, NULL);
 }
 
@@ -178,16 +313,38 @@ void __init zones_init(void)
 
 void __init mem_init(void)
 {
-	max_mapnr = max_low_pfn - ARCH_PFN_OFFSET;
-	high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
-
 #ifdef CONFIG_HIGHMEM
-#error HIGHGMEM not implemented in init.c
+	unsigned long tmp;
+
+	reset_all_zones_managed_pages();
+	for (tmp = max_low_pfn; tmp < max_pfn; tmp++)
+		free_highmem_page(pfn_to_page(tmp));
 #endif
 
+	max_mapnr = max_pfn - ARCH_PFN_OFFSET;
+	high_memory = (void *)__va(max_low_pfn << PAGE_SHIFT);
+
 	free_all_bootmem();
 
 	mem_init_print_info(NULL);
+	pr_info("virtual kernel memory layout:\n"
+#ifdef CONFIG_HIGHMEM
+		"    pkmap   : 0x%08lx - 0x%08lx  (%5lu kB)\n"
+		"    fixmap  : 0x%08lx - 0x%08lx  (%5lu kB)\n"
+#endif
+		"    vmalloc : 0x%08x - 0x%08x  (%5u MB)\n"
+		"    lowmem  : 0x%08x - 0x%08lx  (%5lu MB)\n",
+#ifdef CONFIG_HIGHMEM
+		PKMAP_BASE, PKMAP_BASE + LAST_PKMAP * PAGE_SIZE,
+		(LAST_PKMAP*PAGE_SIZE) >> 10,
+		FIXADDR_START, FIXADDR_TOP,
+		(FIXADDR_TOP - FIXADDR_START) >> 10,
+#endif
+		VMALLOC_START, VMALLOC_END,
+		(VMALLOC_END - VMALLOC_START) >> 20,
+		PAGE_OFFSET, PAGE_OFFSET +
+		(max_low_pfn - min_low_pfn) * PAGE_SIZE,
+		((max_low_pfn - min_low_pfn) * PAGE_SIZE) >> 20);
 }
 
 #ifdef CONFIG_BLK_DEV_INITRD
@@ -204,3 +361,53 @@ void free_initmem(void)
 {
 	free_initmem_default(-1);
 }
+
+static void __init parse_memmap_one(char *p)
+{
+	char *oldp;
+	unsigned long start_at, mem_size;
+
+	if (!p)
+		return;
+
+	oldp = p;
+	mem_size = memparse(p, &p);
+	if (p == oldp)
+		return;
+
+	switch (*p) {
+	case '@':
+		start_at = memparse(p + 1, &p);
+		add_sysmem_bank(start_at, start_at + mem_size);
+		break;
+
+	case '$':
+		start_at = memparse(p + 1, &p);
+		mem_reserve(start_at, start_at + mem_size, 0);
+		break;
+
+	case 0:
+		mem_reserve(mem_size, 0, 0);
+		break;
+
+	default:
+		pr_warn("Unrecognized memmap syntax: %s\n", p);
+		break;
+	}
+}
+
+static int __init parse_memmap_opt(char *str)
+{
+	while (str) {
+		char *k = strchr(str, ',');
+
+		if (k)
+			*k++ = 0;
+
+		parse_memmap_one(str);
+		str = k;
+	}
+
+	return 0;
+}
+early_param("memmap", parse_memmap_opt);
diff --git a/arch/xtensa/mm/mmu.c b/arch/xtensa/mm/mmu.c
index 861203e..3429b48 100644
--- a/arch/xtensa/mm/mmu.c
+++ b/arch/xtensa/mm/mmu.c
@@ -3,6 +3,7 @@
  *
  * Extracted from init.c
  */
+#include <linux/bootmem.h>
 #include <linux/percpu.h>
 #include <linux/init.h>
 #include <linux/string.h>
@@ -16,9 +17,44 @@
 #include <asm/initialize_mmu.h>
 #include <asm/io.h>
 
+#if defined(CONFIG_HIGHMEM)
+static void * __init init_pmd(unsigned long vaddr)
+{
+	pgd_t *pgd = pgd_offset_k(vaddr);
+	pmd_t *pmd = pmd_offset(pgd, vaddr);
+
+	if (pmd_none(*pmd)) {
+		unsigned i;
+		pte_t *pte = alloc_bootmem_low_pages(PAGE_SIZE);
+
+		for (i = 0; i < 1024; i++)
+			pte_clear(NULL, 0, pte + i);
+
+		set_pmd(pmd, __pmd(((unsigned long)pte) & PAGE_MASK));
+		BUG_ON(pte != pte_offset_kernel(pmd, 0));
+		pr_debug("%s: vaddr: 0x%08lx, pmd: 0x%p, pte: 0x%p\n",
+			 __func__, vaddr, pmd, pte);
+		return pte;
+	} else {
+		return pte_offset_kernel(pmd, 0);
+	}
+}
+
+static void __init fixedrange_init(void)
+{
+	BUILD_BUG_ON(FIXADDR_SIZE > PMD_SIZE);
+	init_pmd(__fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK);
+}
+#endif
+
 void __init paging_init(void)
 {
 	memset(swapper_pg_dir, 0, PAGE_SIZE);
+#ifdef CONFIG_HIGHMEM
+	fixedrange_init();
+	pkmap_page_table = init_pmd(PKMAP_BASE);
+	kmap_init();
+#endif
 }
 
 /*
diff --git a/arch/xtensa/mm/tlb.c b/arch/xtensa/mm/tlb.c
index ade62382..5ece856 100644
--- a/arch/xtensa/mm/tlb.c
+++ b/arch/xtensa/mm/tlb.c
@@ -149,6 +149,21 @@ void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
 	local_irq_restore(flags);
 }
 
+void local_flush_tlb_kernel_range(unsigned long start, unsigned long end)
+{
+	if (end > start && start >= TASK_SIZE && end <= PAGE_OFFSET &&
+	    end - start < _TLB_ENTRIES << PAGE_SHIFT) {
+		start &= PAGE_MASK;
+		while (start < end) {
+			invalidate_itlb_mapping(start);
+			invalidate_dtlb_mapping(start);
+			start += PAGE_SIZE;
+		}
+	} else {
+		local_flush_tlb_all();
+	}
+}
+
 #ifdef CONFIG_DEBUG_TLB_SANITY
 
 static unsigned get_pte_for_vaddr(unsigned vaddr)