3 * Utility functions for the Freescale MPC52xx.
5 * Copyright (C) 2006 Sylvain Munaut <tnt@246tNt.com>
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.
15 #include <linux/kernel.h>
16 #include <linux/of_platform.h>
19 #include <asm/mpc52xx.h>
22 * This variable is mapped in mpc52xx_map_wdt() and used in mpc52xx_restart().
23 * Permanent mapping is required because mpc52xx_restart() can be called
24 * from interrupt context while node mapping (which calls ioremap())
25 * cannot be used at such point.
27 static volatile struct mpc52xx_gpt *mpc52xx_wdt = NULL;
30 mpc52xx_map_node(struct device_node *ofn)
33 u64 regaddr64, size64;
38 regaddr_p = of_get_address(ofn, 0, &size64, NULL);
44 regaddr64 = of_translate_address(ofn, regaddr_p);
48 return ioremap((u32)regaddr64, (u32)size64);
52 mpc52xx_find_and_map(const char *compatible)
54 return mpc52xx_map_node(
55 of_find_compatible_node(NULL, NULL, compatible));
58 EXPORT_SYMBOL(mpc52xx_find_and_map);
61 mpc52xx_find_and_map_path(const char *path)
63 return mpc52xx_map_node(of_find_node_by_path(path));
66 EXPORT_SYMBOL(mpc52xx_find_and_map_path);
69 * mpc52xx_find_ipb_freq - Find the IPB bus frequency for a device
72 * Returns IPB bus frequency, or 0 if the bus frequency cannot be found.
75 mpc52xx_find_ipb_freq(struct device_node *node)
77 struct device_node *np;
78 const unsigned int *p_ipb_freq = NULL;
82 p_ipb_freq = of_get_property(node, "bus-frequency", NULL);
86 np = of_get_parent(node);
93 return p_ipb_freq ? *p_ipb_freq : 0;
95 EXPORT_SYMBOL(mpc52xx_find_ipb_freq);
99 * Configure the XLB arbiter settings to match what Linux expects.
102 mpc5200_setup_xlb_arbiter(void)
104 struct mpc52xx_xlb __iomem *xlb;
106 xlb = mpc52xx_find_and_map("mpc5200-xlb");
108 printk(KERN_ERR __FILE__ ": "
109 "Error mapping XLB in mpc52xx_setup_cpu(). "
110 "Expect some abnormal behavior\n");
114 /* Configure the XLB Arbiter priorities */
115 out_be32(&xlb->master_pri_enable, 0xff);
116 out_be32(&xlb->master_priority, 0x11111111);
118 /* Disable XLB pipelining
119 * (cfr errate 292. We could do this only just before ATA PIO
120 * transaction and re-enable it afterwards ...)
122 out_be32(&xlb->config, in_be32(&xlb->config) | MPC52xx_XLB_CFG_PLDIS);
127 static struct of_device_id mpc52xx_bus_ids[] __initdata= {
128 { .compatible = "fsl,mpc5200-immr", },
129 { .compatible = "fsl,lpb", },
131 /* depreciated matches; shouldn't be used in new device trees */
132 { .type = "builtin", .compatible = "mpc5200", }, /* efika */
133 { .type = "soc", .compatible = "mpc5200", }, /* lite5200 */
138 mpc52xx_declare_of_platform_devices(void)
140 /* Find every child of the SOC node and add it to of_platform */
141 if (of_platform_bus_probe(NULL, mpc52xx_bus_ids, NULL))
142 printk(KERN_ERR __FILE__ ": "
143 "Error while probing of_platform bus\n");
147 mpc52xx_map_wdt(void)
150 struct device_node *np;
152 /* mpc52xx_wdt is mapped here and used in mpc52xx_restart,
153 * possibly from a interrupt context. wdt is only implement
154 * on a gpt0, so check has-wdt property before mapping.
156 for_each_compatible_node(np, NULL, "fsl,mpc5200-gpt") {
157 has_wdt = of_get_property(np, "fsl,has-wdt", NULL);
159 mpc52xx_wdt = mpc52xx_map_node(np);
163 for_each_compatible_node(np, NULL, "mpc5200-gpt") {
164 has_wdt = of_get_property(np, "has-wdt", NULL);
166 mpc52xx_wdt = mpc52xx_map_node(np);
173 mpc52xx_restart(char *cmd)
177 /* Turn on the watchdog and wait for it to expire.
178 * It effectively does a reset. */
180 out_be32(&mpc52xx_wdt->mode, 0x00000000);
181 out_be32(&mpc52xx_wdt->count, 0x000000ff);
182 out_be32(&mpc52xx_wdt->mode, 0x00009004);
184 printk("mpc52xx_restart: Can't access wdt. "
185 "Restart impossible, system halted.\n");