1 /* 2 * 3 * Utility functions for the Freescale MPC52xx. 4 * 5 * Copyright (C) 2006 Sylvain Munaut <tnt@246tNt.com> 6 * 7 * This file is licensed under the terms of the GNU General Public License 8 * version 2. This program is licensed "as is" without any warranty of any 9 * kind, whether express or implied. 10 * 11 */ 12 13 #undef DEBUG 14 15 #include <linux/kernel.h> 16 #include <linux/of_platform.h> 17 #include <asm/io.h> 18 #include <asm/prom.h> 19 #include <asm/mpc52xx.h> 20 21 22 void __iomem * 23 mpc52xx_find_and_map(const char *compatible) 24 { 25 struct device_node *ofn; 26 const u32 *regaddr_p; 27 u64 regaddr64, size64; 28 29 ofn = of_find_compatible_node(NULL, NULL, compatible); 30 if (!ofn) 31 return NULL; 32 33 regaddr_p = of_get_address(ofn, 0, &size64, NULL); 34 if (!regaddr_p) { 35 of_node_put(ofn); 36 return NULL; 37 } 38 39 regaddr64 = of_translate_address(ofn, regaddr_p); 40 41 of_node_put(ofn); 42 43 return ioremap((u32)regaddr64, (u32)size64); 44 } 45 EXPORT_SYMBOL(mpc52xx_find_and_map); 46 47 48 /** 49 * mpc52xx_find_ipb_freq - Find the IPB bus frequency for a device 50 * @node: device node 51 * 52 * Returns IPB bus frequency, or 0 if the bus frequency cannot be found. 53 */ 54 unsigned int 55 mpc52xx_find_ipb_freq(struct device_node *node) 56 { 57 struct device_node *np; 58 const unsigned int *p_ipb_freq = NULL; 59 60 of_node_get(node); 61 while (node) { 62 p_ipb_freq = of_get_property(node, "bus-frequency", NULL); 63 if (p_ipb_freq) 64 break; 65 66 np = of_get_parent(node); 67 of_node_put(node); 68 node = np; 69 } 70 if (node) 71 of_node_put(node); 72 73 return p_ipb_freq ? *p_ipb_freq : 0; 74 } 75 EXPORT_SYMBOL(mpc52xx_find_ipb_freq); 76 77 78 /* 79 * Configure the XLB arbiter settings to match what Linux expects. 80 */ 81 void __init 82 mpc5200_setup_xlb_arbiter(void) 83 { 84 struct mpc52xx_xlb __iomem *xlb; 85 86 xlb = mpc52xx_find_and_map("mpc5200-xlb"); 87 if (!xlb) { 88 printk(KERN_ERR __FILE__ ": " 89 "Error mapping XLB in mpc52xx_setup_cpu(). " 90 "Expect some abnormal behavior\n"); 91 return; 92 } 93 94 /* Configure the XLB Arbiter priorities */ 95 out_be32(&xlb->master_pri_enable, 0xff); 96 out_be32(&xlb->master_priority, 0x11111111); 97 98 /* Disable XLB pipelining 99 * (cfr errate 292. We could do this only just before ATA PIO 100 * transaction and re-enable it afterwards ...) 101 */ 102 out_be32(&xlb->config, in_be32(&xlb->config) | MPC52xx_XLB_CFG_PLDIS); 103 104 iounmap(xlb); 105 } 106 107 void __init 108 mpc52xx_declare_of_platform_devices(void) 109 { 110 /* Find every child of the SOC node and add it to of_platform */ 111 if (of_platform_bus_probe(NULL, NULL, NULL)) 112 printk(KERN_ERR __FILE__ ": " 113 "Error while probing of_platform bus\n"); 114 } 115 116