1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * MX35 CPU type detection 4 * 5 * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de> 6 */ 7 #include <linux/module.h> 8 #include <linux/of_address.h> 9 #include <linux/io.h> 10 11 #include "hardware.h" 12 #include "iim.h" 13 14 static int mx35_cpu_rev = -1; 15 16 static int mx35_read_cpu_rev(void) 17 { 18 void __iomem *iim_base; 19 struct device_node *np; 20 u32 rev; 21 22 np = of_find_compatible_node(NULL, NULL, "fsl,imx35-iim"); 23 iim_base = of_iomap(np, 0); 24 of_node_put(np); 25 BUG_ON(!iim_base); 26 27 rev = imx_readl(iim_base + MXC_IIMSREV); 28 switch (rev) { 29 case 0x00: 30 return IMX_CHIP_REVISION_1_0; 31 case 0x10: 32 return IMX_CHIP_REVISION_2_0; 33 case 0x11: 34 return IMX_CHIP_REVISION_2_1; 35 default: 36 return IMX_CHIP_REVISION_UNKNOWN; 37 } 38 } 39 40 int mx35_revision(void) 41 { 42 if (mx35_cpu_rev == -1) 43 mx35_cpu_rev = mx35_read_cpu_rev(); 44 45 return mx35_cpu_rev; 46 } 47 EXPORT_SYMBOL(mx35_revision); 48