arch/mips/sgi-ip30/ip30-xtalk.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * ip30-xtalk.c - Very basic Crosstalk (XIO) detection support.
   4  *   Copyright (C) 2004-2007 Stanislaw Skowronek <skylark@unaligned.org>
   5  *   Copyright (C) 2009 Johannes Dickgreber <tanzy@gmx.de>
   6  *   Copyright (C) 2007, 2014-2016 Joshua Kinard <kumba@gentoo.org>
   7  */
   8
   9 #include <linux/init.h>
  10 #include <linux/kernel.h>
  11 #include <linux/platform_device.h>
  12 #include <linux/platform_data/sgi-w1.h>
  13 #include <linux/platform_data/xtalk-bridge.h>
  14
  15 #include <asm/xtalk/xwidget.h>
  16 #include <asm/pci/bridge.h>
  17
  18 #define IP30_SWIN_BASE(widget) \
  19                 (0x0000000010000000 | (((unsigned long)(widget)) << 24))
  20
  21 #define IP30_RAW_SWIN_BASE(widget)      (IO_BASE + IP30_SWIN_BASE(widget))
  22
  23 #define IP30_SWIN_SIZE          (1 << 24)
  24
  25 #define IP30_WIDGET_XBOW        _AC(0x0, UL)    /* XBow is always 0 */
  26 #define IP30_WIDGET_HEART       _AC(0x8, UL)    /* HEART is always 8 */
  27 #define IP30_WIDGET_PCI_BASE    _AC(0xf, UL)    /* BaseIO PCI is always 15 */
  28
  29 #define XTALK_NODEV             0xffffffff
  30
  31 #define XBOW_REG_LINK_STAT_0    0x114
  32 #define XBOW_REG_LINK_BLK_SIZE  0x40
  33 #define XBOW_REG_LINK_ALIVE     0x80000000
  34
  35 #define HEART_INTR_ADDR         0x00000080
  36
  37 #define xtalk_read      __raw_readl
  38
  39 static void bridge_platform_create(int widget, int masterwid)
  40 {
  41         struct xtalk_bridge_platform_data *bd;
  42         struct sgi_w1_platform_data *wd;
  43         struct platform_device *pdev;
  44         struct resource w1_res;
  45
  46         wd = kzalloc(sizeof(*wd), GFP_KERNEL);
  47         if (!wd)
  48                 goto no_mem;
  49
  50         snprintf(wd->dev_id, sizeof(wd->dev_id), "bridge-%012lx",
  51                  IP30_SWIN_BASE(widget));
  52
  53         memset(&w1_res, 0, sizeof(w1_res));
  54         w1_res.start = IP30_SWIN_BASE(widget) +
  55                                 offsetof(struct bridge_regs, b_nic);
  56         w1_res.end = w1_res.start + 3;
  57         w1_res.flags = IORESOURCE_MEM;
  58
  59         pdev = platform_device_alloc("sgi_w1", PLATFORM_DEVID_AUTO);
  60         if (!pdev) {
  61                 kfree(wd);
  62                 goto no_mem;
  63         }
  64         platform_device_add_resources(pdev, &w1_res, 1);
  65         platform_device_add_data(pdev, wd, sizeof(*wd));
  66         platform_device_add(pdev);
  67
  68         bd = kzalloc(sizeof(*bd), GFP_KERNEL);
  69         if (!bd)
  70                 goto no_mem;
  71         pdev = platform_device_alloc("xtalk-bridge", PLATFORM_DEVID_AUTO);
  72         if (!pdev) {
  73                 kfree(bd);
  74                 goto no_mem;
  75         }
  76
  77         bd->bridge_addr = IP30_RAW_SWIN_BASE(widget);
  78         bd->intr_addr   = HEART_INTR_ADDR;
  79         bd->nasid       = 0;
  80         bd->masterwid   = masterwid;
  81
  82         bd->mem.name    = "Bridge PCI MEM";
  83         bd->mem.start   = IP30_SWIN_BASE(widget) + BRIDGE_DEVIO0;
  84         bd->mem.end     = IP30_SWIN_BASE(widget) + IP30_SWIN_SIZE - 1;
  85         bd->mem.flags   = IORESOURCE_MEM;
  86         bd->mem_offset  = IP30_SWIN_BASE(widget);
  87
  88         bd->io.name     = "Bridge PCI IO";
  89         bd->io.start    = IP30_SWIN_BASE(widget) + BRIDGE_DEVIO0;
  90         bd->io.end      = IP30_SWIN_BASE(widget) + IP30_SWIN_SIZE - 1;
  91         bd->io.flags    = IORESOURCE_IO;
  92         bd->io_offset   = IP30_SWIN_BASE(widget);
  93
  94         platform_device_add_data(pdev, bd, sizeof(*bd));
  95         platform_device_add(pdev);
  96         pr_info("xtalk:%x bridge widget\n", widget);
  97         return;
  98
  99 no_mem:
 100         pr_warn("xtalk:%x bridge create out of memory\n", widget);
 101 }
 102
 103 static unsigned int __init xbow_widget_active(s8 wid)
 104 {
 105         unsigned int link_stat;
 106
 107         link_stat = xtalk_read((void *)(IP30_RAW_SWIN_BASE(IP30_WIDGET_XBOW) +
 108                                         XBOW_REG_LINK_STAT_0 +
 109                                         XBOW_REG_LINK_BLK_SIZE *
 110                                         (wid - 8)));
 111
 112         return (link_stat & XBOW_REG_LINK_ALIVE) ? 1 : 0;
 113 }
 114
 115 static void __init xtalk_init_widget(s8 wid, s8 masterwid)
 116 {
 117         xwidget_part_num_t partnum;
 118         widgetreg_t widget_id;
 119
 120         if (!xbow_widget_active(wid))
 121                 return;
 122
 123         widget_id = xtalk_read((void *)(IP30_RAW_SWIN_BASE(wid) + WIDGET_ID));
 124
 125         partnum = XWIDGET_PART_NUM(widget_id);
 126
 127         switch (partnum) {
 128         case BRIDGE_WIDGET_PART_NUM:
 129         case XBRIDGE_WIDGET_PART_NUM:
 130                 bridge_platform_create(wid, masterwid);
 131                 break;
 132         default:
 133                 pr_info("xtalk:%x unknown widget (0x%x)\n", wid, partnum);
 134                 break;
 135         }
 136 }
 137
 138 static int __init ip30_xtalk_init(void)
 139 {
 140         int i;
 141
 142         /*
 143          * Walk widget IDs backwards so that BaseIO is probed first.  This
 144          * ensures that the BaseIO IOC3 is always detected as eth0.
 145          */
 146         for (i = IP30_WIDGET_PCI_BASE; i > IP30_WIDGET_HEART; i--)
 147                 xtalk_init_widget(i, IP30_WIDGET_HEART);
 148
 149         return 0;
 150 }
 151
 152 arch_initcall(ip30_xtalk_init);