1 /* 2 * MX25 CPU type detection 3 * 4 * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de> 5 * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation; either version 2 of the License, or 10 * (at your option) any later version. 11 */ 12 #include <linux/module.h> 13 #include <linux/io.h> 14 #include <linux/of.h> 15 #include <linux/of_address.h> 16 17 #include "iim.h" 18 #include "hardware.h" 19 20 static int mx25_cpu_rev = -1; 21 22 static int mx25_read_cpu_rev(void) 23 { 24 u32 rev; 25 void __iomem *iim_base; 26 struct device_node *np; 27 28 np = of_find_compatible_node(NULL, NULL, "fsl,imx25-iim"); 29 iim_base = of_iomap(np, 0); 30 BUG_ON(!iim_base); 31 rev = readl(iim_base + MXC_IIMSREV); 32 iounmap(iim_base); 33 34 switch (rev) { 35 case 0x00: 36 return IMX_CHIP_REVISION_1_0; 37 case 0x01: 38 return IMX_CHIP_REVISION_1_1; 39 default: 40 return IMX_CHIP_REVISION_UNKNOWN; 41 } 42 } 43 44 int mx25_revision(void) 45 { 46 if (mx25_cpu_rev == -1) 47 mx25_cpu_rev = mx25_read_cpu_rev(); 48 49 return mx25_cpu_rev; 50 } 51 EXPORT_SYMBOL(mx25_revision); 52