arch/sh/drivers/pci/pci-dreamcast.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * PCI support for the Sega Dreamcast
   4  *
   5  * Copyright (C) 2001, 2002  M. R. Brown
   6  * Copyright (C) 2002, 2003  Paul Mundt
   7  *
   8  * This file originally bore the message (with enclosed-$):
   9  *      Id: pci.c,v 1.3 2003/05/04 19:29:46 lethal Exp
  10  *      Dreamcast PCI: Supports SEGA Broadband Adaptor only.
  11  */
  12
  13 #include <linux/sched.h>
  14 #include <linux/kernel.h>
  15 #include <linux/param.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/init.h>
  18 #include <linux/irq.h>
  19 #include <linux/pci.h>
  20 #include <linux/module.h>
  21 #include <asm/io.h>
  22 #include <asm/irq.h>
  23 #include <mach/pci.h>
  24
  25 static struct resource gapspci_resources[] = {
  26         {
  27                 .name   = "GAPSPCI IO",
  28                 .start  = GAPSPCI_BBA_CONFIG,
  29                 .end    = GAPSPCI_BBA_CONFIG + GAPSPCI_BBA_CONFIG_SIZE - 1,
  30                 .flags  = IORESOURCE_IO,
  31         },  {
  32                 .name   = "GAPSPCI mem",
  33                 .start  = GAPSPCI_DMA_BASE,
  34                 .end    = GAPSPCI_DMA_BASE + GAPSPCI_DMA_SIZE - 1,
  35                 .flags  = IORESOURCE_MEM,
  36         },
  37 };
  38
  39 static struct pci_channel dreamcast_pci_controller = {
  40         .pci_ops        = &gapspci_pci_ops,
  41         .resources      = gapspci_resources,
  42         .nr_resources   = ARRAY_SIZE(gapspci_resources),
  43         .io_offset      = 0x00000000,
  44         .mem_offset     = 0x00000000,
  45 };
  46
  47 /*
  48  * gapspci init
  49  */
  50
  51 static int __init gapspci_init(void)
  52 {
  53         char idbuf[16];
  54         int i;
  55
  56         /*
  57          * FIXME: All of this wants documenting to some degree,
  58          * even some basic register definitions would be nice.
  59          *
  60          * I haven't seen anything this ugly since.. maple.
  61          */
  62
  63         for (i=0; i<16; i++)
  64                 idbuf[i] = inb(GAPSPCI_REGS+i);
  65
  66         if (strncmp(idbuf, "GAPSPCI_BRIDGE_2", 16))
  67                 return -ENODEV;
  68
  69         outl(0x5a14a501, GAPSPCI_REGS+0x18);
  70
  71         for (i=0; i<1000000; i++)
  72                 cpu_relax();
  73
  74         if (inl(GAPSPCI_REGS+0x18) != 1)
  75                 return -EINVAL;
  76
  77         outl(0x01000000, GAPSPCI_REGS+0x20);
  78         outl(0x01000000, GAPSPCI_REGS+0x24);
  79
  80         outl(GAPSPCI_DMA_BASE, GAPSPCI_REGS+0x28);
  81         outl(GAPSPCI_DMA_BASE+GAPSPCI_DMA_SIZE, GAPSPCI_REGS+0x2c);
  82
  83         outl(1, GAPSPCI_REGS+0x14);
  84         outl(1, GAPSPCI_REGS+0x34);
  85
  86         /* Setting Broadband Adapter */
  87         outw(0xf900, GAPSPCI_BBA_CONFIG+0x06);
  88         outl(0x00000000, GAPSPCI_BBA_CONFIG+0x30);
  89         outb(0x00, GAPSPCI_BBA_CONFIG+0x3c);
  90         outb(0xf0, GAPSPCI_BBA_CONFIG+0x0d);
  91         outw(0x0006, GAPSPCI_BBA_CONFIG+0x04);
  92         outl(0x00002001, GAPSPCI_BBA_CONFIG+0x10);
  93         outl(0x01000000, GAPSPCI_BBA_CONFIG+0x14);
  94
  95         return register_pci_controller(&dreamcast_pci_controller);
  96 }
  97 arch_initcall(gapspci_init);