LXR linux/arch/mips/ar7/memory.c

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Copyright (C) 2007 Felix Fietkau <nbd@openwrt.org>
   4 * Copyright (C) 2007 Eugene Konev <ejka@openwrt.org>
   5 */
   6#include <linux/memblock.h>
   7#include <linux/init.h>
   8#include <linux/mm.h>
   9#include <linux/pfn.h>
  10#include <linux/proc_fs.h>
  11#include <linux/string.h>
  12#include <linux/swap.h>
  13
  14#include <asm/bootinfo.h>
  15#include <asm/page.h>
  16#include <asm/sections.h>
  17
  18#include <asm/mach-ar7/ar7.h>
  19
  20static int __init memsize(void)
  21{
  22        u32 size = (64 << 20);
  23        u32 *addr = (u32 *)KSEG1ADDR(AR7_SDRAM_BASE + size - 4);
  24        u32 *kernel_end = (u32 *)KSEG1ADDR(CPHYSADDR((u32)&_end));
  25        u32 *tmpaddr = addr;
  26
  27        while (tmpaddr > kernel_end) {
  28                *tmpaddr = (u32)tmpaddr;
  29                size >>= 1;
  30                tmpaddr -= size >> 2;
  31        }
  32
  33        do {
  34                tmpaddr += size >> 2;
  35                if (*tmpaddr != (u32)tmpaddr)
  36                        break;
  37                size <<= 1;
  38        } while (size < (64 << 20));
  39
  40        writel((u32)tmpaddr, &addr);
  41
  42        return size;
  43}
  44
  45void __init prom_meminit(void)
  46{
  47        unsigned long pages;
  48
  49        pages = memsize() >> PAGE_SHIFT;
  50        memblock_add(PHYS_OFFSET, pages << PAGE_SHIFT);
  51}
  52