/* * * Utility functions for the Freescale MPC52xx. * * Copyright (C) 2006 Sylvain Munaut * * This file is licensed under the terms of the GNU General Public License * version 2. This program is licensed "as is" without any warranty of any * kind, whether express or implied. * */ #undef DEBUG #include #include #include #include #include #include /* MPC5200 device tree match tables */ static struct of_device_id mpc52xx_xlb_ids[] __initdata = { { .compatible = "fsl,mpc5200-xlb", }, { .compatible = "mpc5200-xlb", }, {} }; static struct of_device_id mpc52xx_bus_ids[] __initdata = { { .compatible = "fsl,mpc5200-immr", }, { .compatible = "fsl,mpc5200b-immr", }, { .compatible = "simple-bus", }, /* depreciated matches; shouldn't be used in new device trees */ { .compatible = "fsl,lpb", }, { .type = "builtin", .compatible = "mpc5200", }, /* efika */ { .type = "soc", .compatible = "mpc5200", }, /* lite5200 */ {} }; /* * This variable is mapped in mpc52xx_map_wdt() and used in mpc52xx_restart(). * Permanent mapping is required because mpc52xx_restart() can be called * from interrupt context while node mapping (which calls ioremap()) * cannot be used at such point. */ static DEFINE_SPINLOCK(mpc52xx_lock); static struct mpc52xx_gpt __iomem *mpc52xx_wdt; static struct mpc52xx_cdm __iomem *mpc52xx_cdm; /** * mpc52xx_find_ipb_freq - Find the IPB bus frequency for a device * @node: device node * * Returns IPB bus frequency, or 0 if the bus frequency cannot be found. */ unsigned int mpc52xx_find_ipb_freq(struct device_node *node) { struct device_node *np; const unsigned int *p_ipb_freq = NULL; of_node_get(node); while (node) { p_ipb_freq = of_get_property(node, "bus-frequency", NULL); if (p_ipb_freq) break; np = of_get_parent(node); of_node_put(node); node = np; } if (node) of_node_put(node); return p_ipb_freq ? *p_ipb_freq : 0; } EXPORT_SYMBOL(mpc52xx_find_ipb_freq); /* * Configure the XLB arbiter settings to match what Linux expects. */ void __init mpc5200_setup_xlb_arbiter(void) { struct device_node *np; struct mpc52xx_xlb __iomem *xlb; np = of_find_matching_node(NULL, mpc52xx_xlb_ids); xlb = of_iomap(np, 0); of_node_put(np); if (!xlb) { printk(KERN_ERR __FILE__ ": " "Error mapping XLB in mpc52xx_setup_cpu(). " "Expect some abnormal behavior\n"); return; } /* Configure the XLB Arbiter priorities */ out_be32(&xlb->master_pri_enable, 0xff); out_be32(&xlb->master_priority, 0x11111111); /* * Disable XLB pipelining * (cfr errate 292. We could do this only just before ATA PIO * transaction and re-enable it afterwards ...) * Not needed on MPC5200B. */ if ((mfspr(SPRN_SVR) & MPC5200_SVR_MASK) == MPC5200_SVR) out_be32(&xlb->config, in_be32(&xlb->config) | MPC52xx_XLB_CFG_PLDIS); iounmap(xlb); } /** * mpc52xx_declare_of_platform_devices: register internal devices and children * of the localplus bus to the of_platform * bus. */ void __init mpc52xx_declare_of_platform_devices(void) { /* Find every child of the SOC node and add it to of_platform */ if (of_platform_bus_probe(NULL, mpc52xx_bus_ids, NULL)) printk(KERN_ERR __FILE__ ": " "Error while probing of_platform bus\n"); } /* * match tables used by mpc52xx_map_common_devices() */ static struct of_device_id mpc52xx_gpt_ids[] __initdata = { { .compatible = "fsl,mpc5200-gpt", }, { .compatible = "mpc5200-gpt", }, /* old */ {} }; static struct of_device_id mpc52xx_cdm_ids[] __initdata = { { .compatible = "fsl,mpc5200-cdm", }, { .compatible = "mpc5200-cdm", }, /* old */ {} }; /** * mpc52xx_map_common_devices: iomap devices required by common code */ void __init mpc52xx_map_common_devices(void) { struct device_node *np; /* mpc52xx_wdt is mapped here and used in mpc52xx_restart, * possibly from a interrupt context. wdt is only implement * on a gpt0, so check has-wdt property before mapping. */ for_each_matching_node(np, mpc52xx_gpt_ids) { if (of_get_property(np, "fsl,has-wdt", NULL) || of_get_property(np, "has-wdt", NULL)) { mpc52xx_wdt = of_iomap(np, 0); of_node_put(np); break; } } /* Clock Distribution Module, used by PSC clock setting function */ np = of_find_matching_node(NULL, mpc52xx_cdm_ids); mpc52xx_cdm = of_iomap(np, 0); of_node_put(np); } /** * mpc52xx_set_psc_clkdiv: Set clock divider in the CDM for PSC ports * * @psc_id: id of psc port; must be 1,2,3 or 6 * @clkdiv: clock divider value to put into CDM PSC register. */ int mpc52xx_set_psc_clkdiv(int psc_id, int clkdiv) { unsigned long flags; u16 __iomem *reg; u32 val; u32 mask; u32 mclken_div; if (!mpc52xx_cdm) return -ENODEV; mclken_div = 0x8000 | (clkdiv & 0x1FF); switch (psc_id) { case 1: reg = &mpc52xx_cdm->mclken_div_psc1; mask = 0x20; break; case 2: reg = &mpc52xx_cdm->mclken_div_psc2; mask = 0x40; break; case 3: reg = &mpc52xx_cdm->mclken_div_psc3; mask = 0x80; break; case 6: reg = &mpc52xx_cdm->mclken_div_psc6; mask = 0x10; break; default: return -ENODEV; } /* Set the rate and enable the clock */ spin_lock_irqsave(&mpc52xx_lock, flags); out_be16(reg, mclken_div); val = in_be32(&mpc52xx_cdm->clk_enables); out_be32(&mpc52xx_cdm->clk_enables, val | mask); spin_unlock_irqrestore(&mpc52xx_lock, flags); return 0; } EXPORT_SYMBOL(mpc52xx_set_psc_clkdiv); /** * mpc52xx_restart: ppc_md->restart hook for mpc5200 using the watchdog timer */ void mpc52xx_restart(char *cmd) { local_irq_disable(); /* Turn on the watchdog and wait for it to expire. * It effectively does a reset. */ if (mpc52xx_wdt) { out_be32(&mpc52xx_wdt->mode, 0x00000000); out_be32(&mpc52xx_wdt->count, 0x000000ff); out_be32(&mpc52xx_wdt->mode, 0x00009004); } else printk(KERN_ERR __FILE__ ": " "mpc52xx_restart: Can't access wdt. " "Restart impossible, system halted.\n"); while (1); }