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authorHaavard Skinnemoen <hskinnemoen@atmel.com>2006-09-26 10:32:13 +0400
committerLinus Torvalds <torvalds@g5.osdl.org>2006-09-26 19:48:54 +0400
commit5f97f7f9400de47ae837170bb274e90ad3934386 (patch)
tree514451e6dc6b46253293a00035d375e77b1c65ed /arch/avr32/mm/init.c
parent53e62d3aaa60590d4a69b4e07c29f448b5151047 (diff)
downloadlinux-5f97f7f9400de47ae837170bb274e90ad3934386.tar.xz
[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/init.c')
-rw-r--r--arch/avr32/mm/init.c480
1 files changed, 480 insertions, 0 deletions
diff --git a/arch/avr32/mm/init.c b/arch/avr32/mm/init.c
new file mode 100644
index 000000000000..3e6c41039808
--- /dev/null
+++ b/arch/avr32/mm/init.c
@@ -0,0 +1,480 @@
+/*
+ * 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/kernel.h>
+#include <linux/mm.h>
+#include <linux/swap.h>
+#include <linux/init.h>
+#include <linux/initrd.h>
+#include <linux/mmzone.h>
+#include <linux/bootmem.h>
+#include <linux/pagemap.h>
+#include <linux/pfn.h>
+#include <linux/nodemask.h>
+
+#include <asm/page.h>
+#include <asm/mmu_context.h>
+#include <asm/tlb.h>
+#include <asm/io.h>
+#include <asm/dma.h>
+#include <asm/setup.h>
+#include <asm/sections.h>
+
+DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
+
+pgd_t swapper_pg_dir[PTRS_PER_PGD];
+
+struct page *empty_zero_page;
+
+/*
+ * Cache of MMU context last used.
+ */
+unsigned long mmu_context_cache = NO_CONTEXT;
+
+#define START_PFN (NODE_DATA(0)->bdata->node_boot_start >> PAGE_SHIFT)
+#define MAX_LOW_PFN (NODE_DATA(0)->bdata->node_low_pfn)
+
+void show_mem(void)
+{
+ int total = 0, reserved = 0, cached = 0;
+ int slab = 0, free = 0, shared = 0;
+ pg_data_t *pgdat;
+
+ printk("Mem-info:\n");
+ show_free_areas();
+
+ for_each_online_pgdat(pgdat) {
+ struct page *page, *end;
+
+ page = pgdat->node_mem_map;
+ end = page + pgdat->node_spanned_pages;
+
+ do {
+ total++;
+ if (PageReserved(page))
+ reserved++;
+ else if (PageSwapCache(page))
+ cached++;
+ else if (PageSlab(page))
+ slab++;
+ else if (!page_count(page))
+ free++;
+ else
+ shared += page_count(page) - 1;
+ page++;
+ } while (page < end);
+ }
+
+ printk ("%d pages of RAM\n", total);
+ printk ("%d free pages\n", free);
+ printk ("%d reserved pages\n", reserved);
+ printk ("%d slab pages\n", slab);
+ printk ("%d pages shared\n", shared);
+ printk ("%d pages swap cached\n", cached);
+}
+
+static void __init print_memory_map(const char *what,
+ struct tag_mem_range *mem)
+{
+ printk ("%s:\n", what);
+ for (; mem; mem = mem->next) {
+ printk (" %08lx - %08lx\n",
+ (unsigned long)mem->addr,
+ (unsigned long)(mem->addr + mem->size));
+ }
+}
+
+#define MAX_LOWMEM HIGHMEM_START
+#define MAX_LOWMEM_PFN PFN_DOWN(MAX_LOWMEM)
+
+/*
+ * Sort a list of memory regions in-place by ascending address.
+ *
+ * We're using bubble sort because we only have singly linked lists
+ * with few elements.
+ */
+static void __init sort_mem_list(struct tag_mem_range **pmem)
+{
+ int done;
+ struct tag_mem_range **a, **b;
+
+ if (!*pmem)
+ return;
+
+ do {
+ done = 1;
+ a = pmem, b = &(*pmem)->next;
+ while (*b) {
+ if ((*a)->addr > (*b)->addr) {
+ struct tag_mem_range *tmp;
+ tmp = (*b)->next;
+ (*b)->next = *a;
+ *a = *b;
+ *b = tmp;
+ done = 0;
+ }
+ a = &(*a)->next;
+ b = &(*a)->next;
+ }
+ } while (!done);
+}
+
+/*
+ * Find a free memory region large enough for storing the
+ * bootmem bitmap.
+ */
+static unsigned long __init
+find_bootmap_pfn(const struct tag_mem_range *mem)
+{
+ unsigned long bootmap_pages, bootmap_len;
+ unsigned long node_pages = PFN_UP(mem->size);
+ unsigned long bootmap_addr = mem->addr;
+ struct tag_mem_range *reserved = mem_reserved;
+ struct tag_mem_range *ramdisk = mem_ramdisk;
+ unsigned long kern_start = virt_to_phys(_stext);
+ unsigned long kern_end = virt_to_phys(_end);
+
+ bootmap_pages = bootmem_bootmap_pages(node_pages);
+ bootmap_len = bootmap_pages << PAGE_SHIFT;
+
+ /*
+ * Find a large enough region without reserved pages for
+ * storing the bootmem bitmap. We can take advantage of the
+ * fact that all lists have been sorted.
+ *
+ * We have to check explicitly reserved regions as well as the
+ * kernel image and any RAMDISK images...
+ *
+ * Oh, and we have to make sure we don't overwrite the taglist
+ * since we're going to use it until the bootmem allocator is
+ * fully up and running.
+ */
+ while (1) {
+ if ((bootmap_addr < kern_end) &&
+ ((bootmap_addr + bootmap_len) > kern_start))
+ bootmap_addr = kern_end;
+
+ while (reserved &&
+ (bootmap_addr >= (reserved->addr + reserved->size)))
+ reserved = reserved->next;
+
+ if (reserved &&
+ ((bootmap_addr + bootmap_len) >= reserved->addr)) {
+ bootmap_addr = reserved->addr + reserved->size;
+ continue;
+ }
+
+ while (ramdisk &&
+ (bootmap_addr >= (ramdisk->addr + ramdisk->size)))
+ ramdisk = ramdisk->next;
+
+ if (!ramdisk ||
+ ((bootmap_addr + bootmap_len) < ramdisk->addr))
+ break;
+
+ bootmap_addr = ramdisk->addr + ramdisk->size;
+ }
+
+ if ((PFN_UP(bootmap_addr) + bootmap_len) >= (mem->addr + mem->size))
+ return ~0UL;
+
+ return PFN_UP(bootmap_addr);
+}
+
+void __init setup_bootmem(void)
+{
+ unsigned bootmap_size;
+ unsigned long first_pfn, bootmap_pfn, pages;
+ unsigned long max_pfn, max_low_pfn;
+ unsigned long kern_start = virt_to_phys(_stext);
+ unsigned long kern_end = virt_to_phys(_end);
+ unsigned node = 0;
+ struct tag_mem_range *bank, *res;
+
+ sort_mem_list(&mem_phys);
+ sort_mem_list(&mem_reserved);
+
+ print_memory_map("Physical memory", mem_phys);
+ print_memory_map("Reserved memory", mem_reserved);
+
+ nodes_clear(node_online_map);
+
+ if (mem_ramdisk) {
+#ifdef CONFIG_BLK_DEV_INITRD
+ initrd_start = __va(mem_ramdisk->addr);
+ initrd_end = initrd_start + mem_ramdisk->size;
+
+ print_memory_map("RAMDISK images", mem_ramdisk);
+ if (mem_ramdisk->next)
+ printk(KERN_WARNING
+ "Warning: Only the first RAMDISK image "
+ "will be used\n");
+ sort_mem_list(&mem_ramdisk);
+#else
+ printk(KERN_WARNING "RAM disk image present, but "
+ "no initrd support in kernel!\n");
+#endif
+ }
+
+ if (mem_phys->next)
+ printk(KERN_WARNING "Only using first memory bank\n");
+
+ for (bank = mem_phys; bank; bank = NULL) {
+ first_pfn = PFN_UP(bank->addr);
+ max_low_pfn = max_pfn = PFN_DOWN(bank->addr + bank->size);
+ bootmap_pfn = find_bootmap_pfn(bank);
+ if (bootmap_pfn > max_pfn)
+ panic("No space for bootmem bitmap!\n");
+
+ if (max_low_pfn > MAX_LOWMEM_PFN) {
+ max_low_pfn = MAX_LOWMEM_PFN;
+#ifndef CONFIG_HIGHMEM
+ /*
+ * Lowmem is memory that can be addressed
+ * directly through P1/P2
+ */
+ printk(KERN_WARNING
+ "Node %u: Only %ld MiB of memory will be used.\n",
+ node, MAX_LOWMEM >> 20);
+ printk(KERN_WARNING "Use a HIGHMEM enabled kernel.\n");
+#else
+#error HIGHMEM is not supported by AVR32 yet
+#endif
+ }
+
+ /* Initialize the boot-time allocator with low memory only. */
+ bootmap_size = init_bootmem_node(NODE_DATA(node), bootmap_pfn,
+ first_pfn, max_low_pfn);
+
+ printk("Node %u: bdata = %p, bdata->node_bootmem_map = %p\n",
+ node, NODE_DATA(node)->bdata,
+ NODE_DATA(node)->bdata->node_bootmem_map);
+
+ /*
+ * Register fully available RAM pages with the bootmem
+ * allocator.
+ */
+ pages = max_low_pfn - first_pfn;
+ free_bootmem_node (NODE_DATA(node), PFN_PHYS(first_pfn),
+ PFN_PHYS(pages));
+
+ /*
+ * Reserve space for the kernel image (if present in
+ * this node)...
+ */
+ if ((kern_start >= PFN_PHYS(first_pfn)) &&
+ (kern_start < PFN_PHYS(max_pfn))) {
+ printk("Node %u: Kernel image %08lx - %08lx\n",
+ node, kern_start, kern_end);
+ reserve_bootmem_node(NODE_DATA(node), kern_start,
+ kern_end - kern_start);
+ }
+
+ /* ...the bootmem bitmap... */
+ reserve_bootmem_node(NODE_DATA(node),
+ PFN_PHYS(bootmap_pfn),
+ bootmap_size);
+
+ /* ...any RAMDISK images... */
+ for (res = mem_ramdisk; res; res = res->next) {
+ if (res->addr > PFN_PHYS(max_pfn))
+ break;
+
+ if (res->addr >= PFN_PHYS(first_pfn)) {
+ printk("Node %u: RAMDISK %08lx - %08lx\n",
+ node,
+ (unsigned long)res->addr,
+ (unsigned long)(res->addr + res->size));
+ reserve_bootmem_node(NODE_DATA(node),
+ res->addr, res->size);
+ }
+ }
+
+ /* ...and any other reserved regions. */
+ for (res = mem_reserved; res; res = res->next) {
+ if (res->addr > PFN_PHYS(max_pfn))
+ break;
+
+ if (res->addr >= PFN_PHYS(first_pfn)) {
+ printk("Node %u: Reserved %08lx - %08lx\n",
+ node,
+ (unsigned long)res->addr,
+ (unsigned long)(res->addr + res->size));
+ reserve_bootmem_node(NODE_DATA(node),
+ res->addr, res->size);
+ }
+ }
+
+ node_set_online(node);
+ }
+}
+
+/*
+ * paging_init() sets up the page tables
+ *
+ * This routine also unmaps the page at virtual kernel address 0, so
+ * that we can trap those pesky NULL-reference errors in the kernel.
+ */
+void __init paging_init(void)
+{
+ extern unsigned long _evba;
+ void *zero_page;
+ int nid;
+
+ /*
+ * Make sure we can handle exceptions before enabling
+ * paging. Not that we should ever _get_ any exceptions this
+ * early, but you never know...
+ */
+ printk("Exception vectors start at %p\n", &_evba);
+ sysreg_write(EVBA, (unsigned long)&_evba);
+
+ /*
+ * Since we are ready to handle exceptions now, we should let
+ * the CPU generate them...
+ */
+ __asm__ __volatile__ ("csrf %0" : : "i"(SR_EM_BIT));
+
+ /*
+ * Allocate the zero page. The allocator will panic if it
+ * can't satisfy the request, so no need to check.
+ */
+ zero_page = alloc_bootmem_low_pages_node(NODE_DATA(0),
+ PAGE_SIZE);
+
+ {
+ pgd_t *pg_dir;
+ int i;
+
+ pg_dir = swapper_pg_dir;
+ sysreg_write(PTBR, (unsigned long)pg_dir);
+
+ for (i = 0; i < PTRS_PER_PGD; i++)
+ pgd_val(pg_dir[i]) = 0;
+
+ enable_mmu();
+ printk ("CPU: Paging enabled\n");
+ }
+
+ for_each_online_node(nid) {
+ pg_data_t *pgdat = NODE_DATA(nid);
+ unsigned long zones_size[MAX_NR_ZONES];
+ unsigned long low, start_pfn;
+
+ start_pfn = pgdat->bdata->node_boot_start;
+ start_pfn >>= PAGE_SHIFT;
+ low = pgdat->bdata->node_low_pfn;
+
+ memset(zones_size, 0, sizeof(zones_size));
+ zones_size[ZONE_NORMAL] = low - start_pfn;
+
+ printk("Node %u: start_pfn = 0x%lx, low = 0x%lx\n",
+ nid, start_pfn, low);
+
+ free_area_init_node(nid, pgdat, zones_size, start_pfn, NULL);
+
+ printk("Node %u: mem_map starts at %p\n",
+ pgdat->node_id, pgdat->node_mem_map);
+ }
+
+ mem_map = NODE_DATA(0)->node_mem_map;
+
+ memset(zero_page, 0, PAGE_SIZE);
+ empty_zero_page = virt_to_page(zero_page);
+ flush_dcache_page(empty_zero_page);
+}
+
+void __init mem_init(void)
+{
+ int codesize, reservedpages, datasize, initsize;
+ int nid, i;
+
+ reservedpages = 0;
+ high_memory = NULL;
+
+ /* this will put all low memory onto the freelists */
+ for_each_online_node(nid) {
+ pg_data_t *pgdat = NODE_DATA(nid);
+ unsigned long node_pages = 0;
+ void *node_high_memory;
+
+ num_physpages += pgdat->node_present_pages;
+
+ if (pgdat->node_spanned_pages != 0)
+ node_pages = free_all_bootmem_node(pgdat);
+
+ totalram_pages += node_pages;
+
+ for (i = 0; i < node_pages; i++)
+ if (PageReserved(pgdat->node_mem_map + i))
+ reservedpages++;
+
+ node_high_memory = (void *)((pgdat->node_start_pfn
+ + pgdat->node_spanned_pages)
+ << PAGE_SHIFT);
+ if (node_high_memory > high_memory)
+ high_memory = node_high_memory;
+ }
+
+ max_mapnr = MAP_NR(high_memory);
+
+ codesize = (unsigned long)_etext - (unsigned long)_text;
+ datasize = (unsigned long)_edata - (unsigned long)_data;
+ initsize = (unsigned long)__init_end - (unsigned long)__init_begin;
+
+ printk ("Memory: %luk/%luk available (%dk kernel code, "
+ "%dk reserved, %dk data, %dk init)\n",
+ (unsigned long)nr_free_pages() << (PAGE_SHIFT - 10),
+ totalram_pages << (PAGE_SHIFT - 10),
+ codesize >> 10,
+ reservedpages << (PAGE_SHIFT - 10),
+ datasize >> 10,
+ initsize >> 10);
+}
+
+static inline void free_area(unsigned long addr, unsigned long end, char *s)
+{
+ unsigned int size = (end - addr) >> 10;
+
+ for (; addr < end; addr += PAGE_SIZE) {
+ struct page *page = virt_to_page(addr);
+ ClearPageReserved(page);
+ init_page_count(page);
+ free_page(addr);
+ totalram_pages++;
+ }
+
+ if (size && s)
+ printk(KERN_INFO "Freeing %s memory: %dK (%lx - %lx)\n",
+ s, size, end - (size << 10), end);
+}
+
+void free_initmem(void)
+{
+ free_area((unsigned long)__init_begin, (unsigned long)__init_end,
+ "init");
+}
+
+#ifdef CONFIG_BLK_DEV_INITRD
+
+static int keep_initrd;
+
+void free_initrd_mem(unsigned long start, unsigned long end)
+{
+ if (!keep_initrd)
+ free_area(start, end, "initrd");
+}
+
+static int __init keepinitrd_setup(char *__unused)
+{
+ keep_initrd = 1;
+ return 1;
+}
+
+__setup("keepinitrd", keepinitrd_setup);
+#endif