microblaze_v8: memory inicialization, MMU, TLB

Reviewed-by: Ingo Molnar <mingo@elte.hu>
Acked-by: John Linn <john.linn@xilinx.com>
Acked-by: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Acked-by: John Williams <john.williams@petalogix.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>

1 files changed, 201 insertions, 0 deletions

diff --git a/arch/microblaze/mm/init.c b/arch/microblaze/mm/init.c
new file mode 100644
index 000000000000..b0c8213cd6cf
--- /dev/null
+++ b/arch/microblaze/mm/init.c
@@ -0,0 +1,201 @@
+/*
+ * Copyright (C) 2007-2008 Michal Simek <monstr@monstr.eu>
+ * Copyright (C) 2006 Atmark Techno, Inc.
+ *
+ * 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/bootmem.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/lmb.h>
+#include <linux/mm.h> /* mem_init */
+#include <linux/initrd.h>
+#include <linux/pagemap.h>
+#include <linux/pfn.h>
+#include <linux/swap.h>
+
+#include <asm/page.h>
+#include <asm/mmu_context.h>
+#include <asm/pgalloc.h>
+#include <asm/sections.h>
+#include <asm/tlb.h>
+
+unsigned int __page_offset;
+/* EXPORT_SYMBOL(__page_offset); */
+
+char *klimit = _end;
+
+/*
+ * Initialize the bootmem system and give it all the memory we
+ * have available.
+ */
+unsigned int memory_start;
+unsigned int memory_end; /* due to mm/nommu.c */
+unsigned int memory_size;
+
+/*
+ * paging_init() sets up the page tables - in fact we've already done this.
+ */
+static void __init paging_init(void)
+{
+        int i;
+        unsigned long zones_size[MAX_NR_ZONES];
+
+        /*
+         * old: we can DMA to/from any address.put all page into ZONE_DMA
+         * We use only ZONE_NORMAL
+         */
+        zones_size[ZONE_NORMAL] = max_mapnr;
+
+        /* every other zones are empty */
+        for (i = 1; i < MAX_NR_ZONES; i++)
+                zones_size[i] = 0;
+
+        free_area_init(zones_size);
+}
+
+void __init setup_memory(void)
+{
+        int i;
+        unsigned long map_size;
+        u32 kernel_align_start, kernel_align_size;
+
+        /* Find main memory where is the kernel */
+        for (i = 0; i < lmb.memory.cnt; i++) {
+                memory_start = (u32) lmb.memory.region[i].base;
+                memory_end = (u32) lmb.memory.region[i].base
+                                + (u32) lmb.memory.region[i].size;
+                if ((memory_start <= (u32)_text) &&
+                                        ((u32)_text <= memory_end)) {
+                        memory_size = memory_end - memory_start;
+                        PAGE_OFFSET = memory_start;
+                        printk(KERN_INFO "%s: Main mem: 0x%x-0x%x, "
+                                "size 0x%08x\n", __func__, memory_start,
+                                                memory_end, memory_size);
+                        break;
+                }
+        }
+
+        if (!memory_start || !memory_end) {
+                panic("%s: Missing memory setting 0x%08x-0x%08x\n",
+                        __func__, memory_start, memory_end);
+        }
+
+        /* reservation of region where is the kernel */
+        kernel_align_start = PAGE_DOWN((u32)_text);
+        /* ALIGN can be remove because _end in vmlinux.lds.S is align */
+        kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start;
+        lmb_reserve(kernel_align_start, kernel_align_size);
+        printk(KERN_INFO "%s: kernel addr=0x%08x-0x%08x size=0x%08x\n",
+                __func__, kernel_align_start, kernel_align_start
+                        + kernel_align_size, kernel_align_size);
+
+        /*
+         * Kernel:
+         * start: base phys address of kernel - page align
+         * end: base phys address of kernel - page align
+         *
+         * min_low_pfn - the first page (mm/bootmem.c - node_boot_start)
+         * max_low_pfn
+         * max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn)
+         * num_physpages - number of all pages
+         */
+
+        /* memory start is from the kernel end (aligned) to higher addr */
+        min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */
+        /* RAM is assumed contiguous */
+        num_physpages = max_mapnr = memory_size >> PAGE_SHIFT;
+        max_pfn = max_low_pfn = memory_end >> PAGE_SHIFT;
+
+        printk(KERN_INFO "%s: max_mapnr: %#lx\n", __func__, max_mapnr);
+        printk(KERN_INFO "%s: min_low_pfn: %#lx\n", __func__, min_low_pfn);
+        printk(KERN_INFO "%s: max_low_pfn: %#lx\n", __func__, max_low_pfn);
+
+        /*
+         * Find an area to use for the bootmem bitmap.
+         * We look for the first area which is at least
+         * 128kB in length (128kB is enough for a bitmap
+         * for 4GB of memory, using 4kB pages), plus 1 page
+         * (in case the address isn't page-aligned).
+         */
+        map_size = init_bootmem_node(NODE_DATA(0), PFN_UP(TOPHYS((u32)_end)),
+                                        min_low_pfn, max_low_pfn);
+
+        lmb_reserve(PFN_UP(TOPHYS((u32)_end)) << PAGE_SHIFT, map_size);
+
+        /* free bootmem is whole main memory */
+        free_bootmem(memory_start, memory_size);
+
+        /* reserve allocate blocks */
+        for (i = 0; i < lmb.reserved.cnt; i++) {
+                pr_debug("reserved %d - 0x%08x-0x%08x\n", i,
+                        (u32) lmb.reserved.region[i].base,
+                        (u32) lmb_size_bytes(&lmb.reserved, i));
+                reserve_bootmem(lmb.reserved.region[i].base,
+                        lmb_size_bytes(&lmb.reserved, i) - 1, BOOTMEM_DEFAULT);
+        }
+        paging_init();
+}
+
+void free_init_pages(char *what, unsigned long begin, unsigned long end)
+{
+        unsigned long addr;
+
+        for (addr = begin; addr < end; addr += PAGE_SIZE) {
+                ClearPageReserved(virt_to_page(addr));
+                init_page_count(virt_to_page(addr));
+                memset((void *)addr, 0xcc, PAGE_SIZE);
+                free_page(addr);
+                totalram_pages++;
+        }
+        printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
+}
+
+#ifdef CONFIG_BLK_DEV_INITRD
+void free_initrd_mem(unsigned long start, unsigned long end)
+{
+        int pages = 0;
+        for (; start < end; start += PAGE_SIZE) {
+                ClearPageReserved(virt_to_page(start));
+                init_page_count(virt_to_page(start));
+                free_page(start);
+                totalram_pages++;
+                pages++;
+        }
+        printk(KERN_NOTICE "Freeing initrd memory: %dk freed\n", pages);
+}
+#endif
+
+void free_initmem(void)
+{
+        free_init_pages("unused kernel memory",
+                        (unsigned long)(&__init_begin),
+                        (unsigned long)(&__init_end));
+}
+
+/* FIXME from arch/powerpc/mm/mem.c*/
+void show_mem(void)
+{
+        printk(KERN_NOTICE "%s\n", __func__);
+}
+
+void __init mem_init(void)
+{
+        high_memory = (void *)__va(memory_end);
+        /* this will put all memory onto the freelists */
+        totalram_pages += free_all_bootmem();
+
+        printk(KERN_INFO "Memory: %luk/%luk available\n",
+               (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
+               num_physpages << (PAGE_SHIFT-10));
+}
+
+/* Check against bounds of physical memory */
+int ___range_ok(unsigned long addr, unsigned long size)
+{
+        return ((addr < memory_start) ||
+                ((addr + size) > memory_end));
+}