arch/powerpc/platforms/44x/ppc476.c

   1 /*
   2  * PowerPC 476FPE board specific routines
   3  *
   4  * Copyright © 2013 Tony Breeds IBM Corporation
   5  * Copyright © 2013 Alistair Popple IBM Corporation
   6  *
   7  * Based on earlier code:
   8  *    Matt Porter <mporter@kernel.crashing.org>
   9  *    Copyright 2002-2005 MontaVista Software Inc.
  10  *
  11  *    Eugene Surovegin <eugene.surovegin@zultys.com> or <ebs@ebshome.net>
  12  *    Copyright (c) 2003-2005 Zultys Technologies
  13  *
  14  *    Rewritten and ported to the merged powerpc tree:
  15  *    Copyright 2007 David Gibson <dwg@au1.ibm.com>, IBM Corporation.
  16  *    Copyright © 2011 David Kliekamp IBM Corporation
  17  *
  18  * This program is free software; you can redistribute  it and/or modify it
  19  * under  the terms of  the GNU General  Public License as published by the
  20  * Free Software Foundation;  either version 2 of the  License, or (at your
  21  * option) any later version.
  22  */
  23
  24 #include <linux/init.h>
  25 #include <linux/of.h>
  26 #include <linux/of_platform.h>
  27 #include <linux/rtc.h>
  28
  29 #include <asm/machdep.h>
  30 #include <asm/prom.h>
  31 #include <asm/udbg.h>
  32 #include <asm/time.h>
  33 #include <asm/uic.h>
  34 #include <asm/ppc4xx.h>
  35 #include <asm/mpic.h>
  36 #include <asm/mmu.h>
  37
  38 #include <linux/pci.h>
  39 #include <linux/i2c.h>
  40
  41 static struct of_device_id ppc47x_of_bus[] __initdata = {
  42         { .compatible = "ibm,plb4", },
  43         { .compatible = "ibm,plb6", },
  44         { .compatible = "ibm,opb", },
  45         { .compatible = "ibm,ebc", },
  46         {},
  47 };
  48
  49 /* The EEPROM is missing and the default values are bogus.  This forces USB in
  50  * to EHCI mode */
  51 static void quirk_ppc_currituck_usb_fixup(struct pci_dev *dev)
  52 {
  53         if (of_machine_is_compatible("ibm,currituck")) {
  54                 pci_write_config_dword(dev, 0xe0, 0x0114231f);
  55                 pci_write_config_dword(dev, 0xe4, 0x00006c40);
  56         }
  57 }
  58 DECLARE_PCI_FIXUP_HEADER(0x1033, 0x0035, quirk_ppc_currituck_usb_fixup);
  59
  60 /* Akebono has an AVR microcontroller attached to the I2C bus
  61  * which is used to power off/reset the system. */
  62
  63 /* AVR I2C Commands */
  64 #define AVR_PWRCTL_CMD (0x26)
  65
  66 /* Flags for the power control I2C commands */
  67 #define AVR_PWRCTL_PWROFF (0x01)
  68 #define AVR_PWRCTL_RESET (0x02)
  69
  70 static struct i2c_client *avr_i2c_client;
  71 static void avr_halt_system(int pwrctl_flags)
  72 {
  73         /* Request the AVR to reset the system */
  74         i2c_smbus_write_byte_data(avr_i2c_client,
  75                                   AVR_PWRCTL_CMD, pwrctl_flags);
  76
  77         /* Wait for system to be reset */
  78         while (1)
  79                 ;
  80 }
  81
  82 static void avr_power_off_system(void)
  83 {
  84         avr_halt_system(AVR_PWRCTL_PWROFF);
  85 }
  86
  87 static void avr_reset_system(char *cmd)
  88 {
  89         avr_halt_system(AVR_PWRCTL_RESET);
  90 }
  91
  92 static int avr_probe(struct i2c_client *client,
  93                             const struct i2c_device_id *id)
  94 {
  95         avr_i2c_client = client;
  96         ppc_md.restart = avr_reset_system;
  97         ppc_md.power_off = avr_power_off_system;
  98         return 0;
  99 }
 100
 101 static const struct i2c_device_id avr_id[] = {
 102         { "akebono-avr", 0 },
 103         { }
 104 };
 105
 106 static struct i2c_driver avr_driver = {
 107         .driver = {
 108                 .name = "akebono-avr",
 109         },
 110         .probe = avr_probe,
 111         .id_table = avr_id,
 112 };
 113
 114 static int __init ppc47x_device_probe(void)
 115 {
 116         i2c_add_driver(&avr_driver);
 117         of_platform_bus_probe(NULL, ppc47x_of_bus, NULL);
 118
 119         return 0;
 120 }
 121 machine_device_initcall(ppc47x, ppc47x_device_probe);
 122
 123 static void __init ppc47x_init_irq(void)
 124 {
 125         struct device_node *np;
 126
 127         /* Find top level interrupt controller */
 128         for_each_node_with_property(np, "interrupt-controller") {
 129                 if (of_get_property(np, "interrupts", NULL) == NULL)
 130                         break;
 131         }
 132         if (np == NULL)
 133                 panic("Can't find top level interrupt controller");
 134
 135         /* Check type and do appropriate initialization */
 136         if (of_device_is_compatible(np, "chrp,open-pic")) {
 137                 /* The MPIC driver will get everything it needs from the
 138                  * device-tree, just pass 0 to all arguments
 139                  */
 140                 struct mpic *mpic =
 141                         mpic_alloc(np, 0, MPIC_NO_RESET, 0, 0, " MPIC     ");
 142                 BUG_ON(mpic == NULL);
 143                 mpic_init(mpic);
 144                 ppc_md.get_irq = mpic_get_irq;
 145         } else
 146                 panic("Unrecognized top level interrupt controller");
 147 }
 148
 149 #ifdef CONFIG_SMP
 150 static void smp_ppc47x_setup_cpu(int cpu)
 151 {
 152         mpic_setup_this_cpu();
 153 }
 154
 155 static int smp_ppc47x_kick_cpu(int cpu)
 156 {
 157         struct device_node *cpunode = of_get_cpu_node(cpu, NULL);
 158         const u64 *spin_table_addr_prop;
 159         u32 *spin_table;
 160         extern void start_secondary_47x(void);
 161
 162         BUG_ON(cpunode == NULL);
 163
 164         /* Assume spin table. We could test for the enable-method in
 165          * the device-tree but currently there's little point as it's
 166          * our only supported method
 167          */
 168         spin_table_addr_prop =
 169                 of_get_property(cpunode, "cpu-release-addr", NULL);
 170
 171         if (spin_table_addr_prop == NULL) {
 172                 pr_err("CPU%d: Can't start, missing cpu-release-addr !\n",
 173                        cpu);
 174                 return 1;
 175         }
 176
 177         /* Assume it's mapped as part of the linear mapping. This is a bit
 178          * fishy but will work fine for now
 179          *
 180          * XXX: Is there any reason to assume differently?
 181          */
 182         spin_table = (u32 *)__va(*spin_table_addr_prop);
 183         pr_debug("CPU%d: Spin table mapped at %p\n", cpu, spin_table);
 184
 185         spin_table[3] = cpu;
 186         smp_wmb();
 187         spin_table[1] = __pa(start_secondary_47x);
 188         mb();
 189
 190         return 0;
 191 }
 192
 193 static struct smp_ops_t ppc47x_smp_ops = {
 194         .probe          = smp_mpic_probe,
 195         .message_pass   = smp_mpic_message_pass,
 196         .setup_cpu      = smp_ppc47x_setup_cpu,
 197         .kick_cpu       = smp_ppc47x_kick_cpu,
 198         .give_timebase  = smp_generic_give_timebase,
 199         .take_timebase  = smp_generic_take_timebase,
 200 };
 201
 202 static void __init ppc47x_smp_init(void)
 203 {
 204         if (mmu_has_feature(MMU_FTR_TYPE_47x))
 205                 smp_ops = &ppc47x_smp_ops;
 206 }
 207
 208 #else /* CONFIG_SMP */
 209 static void __init ppc47x_smp_init(void) { }
 210 #endif /* CONFIG_SMP */
 211
 212 static void __init ppc47x_setup_arch(void)
 213 {
 214
 215         /* No need to check the DMA config as we /know/ our windows are all of
 216          * RAM.  Lets hope that doesn't change */
 217         swiotlb_detect_4g();
 218
 219         ppc47x_smp_init();
 220 }
 221
 222 static int board_rev = -1;
 223 static int __init ppc47x_get_board_rev(void)
 224 {
 225         int reg;
 226         u8 *fpga;
 227         struct device_node *np = NULL;
 228
 229         if (of_machine_is_compatible("ibm,currituck")) {
 230                 np = of_find_compatible_node(NULL, NULL, "ibm,currituck-fpga");
 231                 reg = 0;
 232         } else if (of_machine_is_compatible("ibm,akebono")) {
 233                 np = of_find_compatible_node(NULL, NULL, "ibm,akebono-fpga");
 234                 reg = 2;
 235         }
 236
 237         if (!np)
 238                 goto fail;
 239
 240         fpga = (u8 *) of_iomap(np, 0);
 241         of_node_put(np);
 242         if (!fpga)
 243                 goto fail;
 244
 245         board_rev = ioread8(fpga + reg) & 0x03;
 246         pr_info("%s: Found board revision %d\n", __func__, board_rev);
 247         iounmap(fpga);
 248         return 0;
 249
 250 fail:
 251         pr_info("%s: Unable to find board revision\n", __func__);
 252         return 0;
 253 }
 254 machine_arch_initcall(ppc47x, ppc47x_get_board_rev);
 255
 256 /* Use USB controller should have been hardware swizzled but it wasn't :( */
 257 static void ppc47x_pci_irq_fixup(struct pci_dev *dev)
 258 {
 259         if (dev->vendor == 0x1033 && (dev->device == 0x0035 ||
 260                                       dev->device == 0x00e0)) {
 261                 if (board_rev == 0) {
 262                         dev->irq = irq_create_mapping(NULL, 47);
 263                         pr_info("%s: Mapping irq %d\n", __func__, dev->irq);
 264                 } else if (board_rev == 2) {
 265                         dev->irq = irq_create_mapping(NULL, 49);
 266                         pr_info("%s: Mapping irq %d\n", __func__, dev->irq);
 267                 } else {
 268                         pr_alert("%s: Unknown board revision\n", __func__);
 269                 }
 270         }
 271 }
 272
 273 /*
 274  * Called very early, MMU is off, device-tree isn't unflattened
 275  */
 276 static int __init ppc47x_probe(void)
 277 {
 278         unsigned long root = of_get_flat_dt_root();
 279
 280         if (of_flat_dt_is_compatible(root, "ibm,akebono"))
 281                 return 1;
 282
 283         if (of_flat_dt_is_compatible(root, "ibm,currituck")) {
 284                 ppc_md.pci_irq_fixup = ppc47x_pci_irq_fixup;
 285                 return 1;
 286         }
 287
 288         return 0;
 289 }
 290
 291 define_machine(ppc47x) {
 292         .name                   = "PowerPC 47x",
 293         .probe                  = ppc47x_probe,
 294         .progress               = udbg_progress,
 295         .init_IRQ               = ppc47x_init_irq,
 296         .setup_arch             = ppc47x_setup_arch,
 297         .restart                = ppc4xx_reset_system,
 298         .calibrate_decr         = generic_calibrate_decr,
 299 };