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authorHaavard Skinnemoen <hskinnemoen@atmel.com>2006-09-25 23:32:13 -0700
committerLinus Torvalds <torvalds@g5.osdl.org>2006-09-26 08:48:54 -0700
commit5f97f7f9400de47ae837170bb274e90ad3934386 (patch)
tree514451e6dc6b46253293a00035d375e77b1c65ed /arch/avr32/mm/ioremap.c
parent53e62d3aaa60590d4a69b4e07c29f448b5151047 (diff)
downloadlinux-5f97f7f9400de47ae837170bb274e90ad3934386.tar.gz
[PATCH] avr32 architecture
This adds support for the Atmel AVR32 architecture as well as the AT32AP7000 CPU and the AT32STK1000 development board. AVR32 is a new high-performance 32-bit RISC microprocessor core, designed for cost-sensitive embedded applications, with particular emphasis on low power consumption and high code density. The AVR32 architecture is not binary compatible with earlier 8-bit AVR architectures. The AVR32 architecture, including the instruction set, is described by the AVR32 Architecture Manual, available from http://www.atmel.com/dyn/resources/prod_documents/doc32000.pdf The Atmel AT32AP7000 is the first CPU implementing the AVR32 architecture. It features a 7-stage pipeline, 16KB instruction and data caches and a full Memory Management Unit. It also comes with a large set of integrated peripherals, many of which are shared with the AT91 ARM-based controllers from Atmel. Full data sheet is available from http://www.atmel.com/dyn/resources/prod_documents/doc32003.pdf while the CPU core implementation including caches and MMU is documented by the AVR32 AP Technical Reference, available from http://www.atmel.com/dyn/resources/prod_documents/doc32001.pdf Information about the AT32STK1000 development board can be found at http://www.atmel.com/dyn/products/tools_card.asp?tool_id=3918 including a BSP CD image with an earlier version of this patch, development tools (binaries and source/patches) and a root filesystem image suitable for booting from SD card. Alternatively, there's a preliminary "getting started" guide available at http://avr32linux.org/twiki/bin/view/Main/GettingStarted which provides links to the sources and patches you will need in order to set up a cross-compiling environment for avr32-linux. This patch, as well as the other patches included with the BSP and the toolchain patches, is actively supported by Atmel Corporation. [dmccr@us.ibm.com: Fix more pxx_page macro locations] [bunk@stusta.de: fix `make defconfig'] Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Dave McCracken <dmccr@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch/avr32/mm/ioremap.c')
-rw-r--r--arch/avr32/mm/ioremap.c197
1 files changed, 197 insertions, 0 deletions
diff --git a/arch/avr32/mm/ioremap.c b/arch/avr32/mm/ioremap.c
new file mode 100644
index 0000000..5360218
--- /dev/null
+++ b/arch/avr32/mm/ioremap.c
@@ -0,0 +1,197 @@
+/*
+ * Copyright (C) 2004-2006 Atmel Corporation
+ *
+ * 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.
+ */
+#include <linux/vmalloc.h>
+#include <linux/module.h>
+
+#include <asm/io.h>
+#include <asm/pgtable.h>
+#include <asm/cacheflush.h>
+#include <asm/tlbflush.h>
+#include <asm/addrspace.h>
+
+static inline int remap_area_pte(pte_t *pte, unsigned long address,
+ unsigned long end, unsigned long phys_addr,
+ pgprot_t prot)
+{
+ unsigned long pfn;
+
+ pfn = phys_addr >> PAGE_SHIFT;
+ do {
+ WARN_ON(!pte_none(*pte));
+
+ set_pte(pte, pfn_pte(pfn, prot));
+ address += PAGE_SIZE;
+ pfn++;
+ pte++;
+ } while (address && (address < end));
+
+ return 0;
+}
+
+static inline int remap_area_pmd(pmd_t *pmd, unsigned long address,
+ unsigned long end, unsigned long phys_addr,
+ pgprot_t prot)
+{
+ unsigned long next;
+
+ phys_addr -= address;
+
+ do {
+ pte_t *pte = pte_alloc_kernel(pmd, address);
+ if (!pte)
+ return -ENOMEM;
+
+ next = (address + PMD_SIZE) & PMD_MASK;
+ if (remap_area_pte(pte, address, next,
+ address + phys_addr, prot))
+ return -ENOMEM;
+
+ address = next;
+ pmd++;
+ } while (address && (address < end));
+ return 0;
+}
+
+static int remap_area_pud(pud_t *pud, unsigned long address,
+ unsigned long end, unsigned long phys_addr,
+ pgprot_t prot)
+{
+ unsigned long next;
+
+ phys_addr -= address;
+
+ do {
+ pmd_t *pmd = pmd_alloc(&init_mm, pud, address);
+ if (!pmd)
+ return -ENOMEM;
+ next = (address + PUD_SIZE) & PUD_MASK;
+ if (remap_area_pmd(pmd, address, next,
+ phys_addr + address, prot))
+ return -ENOMEM;
+
+ address = next;
+ pud++;
+ } while (address && address < end);
+
+ return 0;
+}
+
+static int remap_area_pages(unsigned long address, unsigned long phys_addr,
+ size_t size, pgprot_t prot)
+{
+ unsigned long end = address + size;
+ unsigned long next;
+ pgd_t *pgd;
+ int err = 0;
+
+ phys_addr -= address;
+
+ pgd = pgd_offset_k(address);
+ flush_cache_all();
+ BUG_ON(address >= end);
+
+ spin_lock(&init_mm.page_table_lock);
+ do {
+ pud_t *pud = pud_alloc(&init_mm, pgd, address);
+
+ err = -ENOMEM;
+ if (!pud)
+ break;
+
+ next = (address + PGDIR_SIZE) & PGDIR_MASK;
+ if (next < address || next > end)
+ next = end;
+ err = remap_area_pud(pud, address, next,
+ phys_addr + address, prot);
+ if (err)
+ break;
+
+ address = next;
+ pgd++;
+ } while (address && (address < end));
+
+ spin_unlock(&init_mm.page_table_lock);
+ flush_tlb_all();
+ return err;
+}
+
+/*
+ * Re-map an arbitrary physical address space into the kernel virtual
+ * address space. Needed when the kernel wants to access physical
+ * memory directly.
+ */
+void __iomem *__ioremap(unsigned long phys_addr, size_t size,
+ unsigned long flags)
+{
+ void *addr;
+ struct vm_struct *area;
+ unsigned long offset, last_addr;
+ pgprot_t prot;
+
+ /*
+ * Check if we can simply use the P4 segment. This area is
+ * uncacheable, so if caching/buffering is requested, we can't
+ * use it.
+ */
+ if ((phys_addr >= P4SEG) && (flags == 0))
+ return (void __iomem *)phys_addr;
+
+ /* Don't allow wraparound or zero size */
+ last_addr = phys_addr + size - 1;
+ if (!size || last_addr < phys_addr)
+ return NULL;
+
+ /*
+ * XXX: When mapping regular RAM, we'd better make damn sure
+ * it's never used for anything else. But this is really the
+ * caller's responsibility...
+ */
+ if (PHYSADDR(P2SEGADDR(phys_addr)) == phys_addr)
+ return (void __iomem *)P2SEGADDR(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_RW | _PAGE_DIRTY
+ | _PAGE_ACCESSED | _PAGE_TYPE_SMALL | flags);
+
+ /*
+ * Ok, go for it..
+ */
+ area = get_vm_area(size, VM_IOREMAP);
+ if (!area)
+ return NULL;
+ area->phys_addr = phys_addr;
+ addr = area->addr;
+ if (remap_area_pages((unsigned long)addr, phys_addr, size, prot)) {
+ vunmap(addr);
+ return NULL;
+ }
+
+ return (void __iomem *)(offset + (char *)addr);
+}
+EXPORT_SYMBOL(__ioremap);
+
+void __iounmap(void __iomem *addr)
+{
+ struct vm_struct *p;
+
+ if ((unsigned long)addr >= P4SEG)
+ return;
+
+ p = remove_vm_area((void *)(PAGE_MASK & (unsigned long __force)addr));
+ if (unlikely(!p)) {
+ printk (KERN_ERR "iounmap: bad address %p\n", addr);
+ return;
+ }
+
+ kfree (p);
+}
+EXPORT_SYMBOL(__iounmap);