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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/avr32/mm/init.c
Initial import
Diffstat (limited to 'arch/avr32/mm/init.c')
-rw-r--r--arch/avr32/mm/init.c125
1 files changed, 125 insertions, 0 deletions
diff --git a/arch/avr32/mm/init.c b/arch/avr32/mm/init.c
new file mode 100644
index 000000000..def5391d9
--- /dev/null
+++ b/arch/avr32/mm/init.c
@@ -0,0 +1,125 @@
+/*
+ * 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/gfp.h>
+#include <linux/mm.h>
+#include <linux/swap.h>
+#include <linux/init.h>
+#include <linux/mmzone.h>
+#include <linux/module.h>
+#include <linux/bootmem.h>
+#include <linux/pagemap.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>
+
+pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_data;
+
+struct page *empty_zero_page;
+EXPORT_SYMBOL(empty_zero_page);
+
+/*
+ * Cache of MMU context last used.
+ */
+unsigned long mmu_context_cache = NO_CONTEXT;
+
+/*
+ * 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);
+
+ sysreg_write(PTBR, (unsigned long)swapper_pg_dir);
+ 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_min_pfn;
+ 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, 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;
+
+ empty_zero_page = virt_to_page(zero_page);
+ flush_dcache_page(empty_zero_page);
+}
+
+void __init mem_init(void)
+{
+ pg_data_t *pgdat;
+
+ high_memory = NULL;
+ for_each_online_pgdat(pgdat)
+ high_memory = max_t(void *, high_memory,
+ __va(pgdat_end_pfn(pgdat) << PAGE_SHIFT));
+
+ set_max_mapnr(MAP_NR(high_memory));
+ free_all_bootmem();
+ mem_init_print_info(NULL);
+}
+
+void free_initmem(void)
+{
+ free_initmem_default(-1);
+}
+
+#ifdef CONFIG_BLK_DEV_INITRD
+void free_initrd_mem(unsigned long start, unsigned long end)
+{
+ free_reserved_area((void *)start, (void *)end, -1, "initrd");
+}
+#endif