MIPS: Add support for Texas Instruments AR7 System-on-a-Chip

This patch adds support for the Texas Instruments AR7 System-on-a-Chip.
It supports the TNETD7100, 7200 and 7300 versions of the SoC.

Signed-off-by: Matteo Croce <matteo@openwrt.org>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Eugene Konev <ejka@openwrt.org>
Signed-off-by: Nicolas Thill <nico@openwrt.org>
Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/ar7/memory.c b/arch/mips/ar7/memory.c
new file mode 100644
index 0000000..46fed44
--- /dev/null
+++ b/arch/mips/ar7/memory.c
@@ -0,0 +1,72 @@
+/*
+ * Copyright (C) 2007 Felix Fietkau <nbd@openwrt.org>
+ * Copyright (C) 2007 Eugene Konev <ejka@openwrt.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+#include <linux/bootmem.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/pfn.h>
+#include <linux/proc_fs.h>
+#include <linux/string.h>
+#include <linux/swap.h>
+
+#include <asm/bootinfo.h>
+#include <asm/page.h>
+#include <asm/sections.h>
+
+#include <asm/mach-ar7/ar7.h>
+#include <asm/mips-boards/prom.h>
+
+static int __init memsize(void)
+{
+	u32 size = (64 << 20);
+	u32 *addr = (u32 *)KSEG1ADDR(AR7_SDRAM_BASE + size - 4);
+	u32 *kernel_end = (u32 *)KSEG1ADDR(CPHYSADDR((u32)&_end));
+	u32 *tmpaddr = addr;
+
+	while (tmpaddr > kernel_end) {
+		*tmpaddr = (u32)tmpaddr;
+		size >>= 1;
+		tmpaddr -= size >> 2;
+	}
+
+	do {
+		tmpaddr += size >> 2;
+		if (*tmpaddr != (u32)tmpaddr)
+			break;
+		size <<= 1;
+	} while (size < (64 << 20));
+
+	writel(tmpaddr, &addr);
+
+	return size;
+}
+
+void __init prom_meminit(void)
+{
+	unsigned long pages;
+
+	pages = memsize() >> PAGE_SHIFT;
+	add_memory_region(PHYS_OFFSET, pages << PAGE_SHIFT,
+			  BOOT_MEM_RAM);
+}
+
+void __init prom_free_prom_memory(void)
+{
+	/* Nothing to free */
+}