drivers/mtd/maps/l440gx.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * BIOS Flash chip on Intel 440GX board.
   4  *
   5  * Bugs this currently does not work under linuxBIOS.
   6  */
   7
   8 #include <linux/module.h>
   9 #include <linux/pci.h>
  10 #include <linux/kernel.h>
  11 #include <linux/init.h>
  12 #include <asm/io.h>
  13 #include <linux/mtd/mtd.h>
  14 #include <linux/mtd/map.h>
  15
  16 #define PIIXE_IOBASE_RESOURCE   11
  17
  18 #define WINDOW_ADDR 0xfff00000
  19 #define WINDOW_SIZE 0x00100000
  20 #define BUSWIDTH 1
  21
  22 static u32 iobase;
  23 #define IOBASE iobase
  24 #define TRIBUF_PORT (IOBASE+0x37)
  25 #define VPP_PORT (IOBASE+0x28)
  26
  27 static struct mtd_info *mymtd;
  28
  29
  30 /* Is this really the vpp port? */
  31 static DEFINE_SPINLOCK(l440gx_vpp_lock);
  32 static int l440gx_vpp_refcnt;
  33 static void l440gx_set_vpp(struct map_info *map, int vpp)
  34 {
  35         unsigned long flags;
  36
  37         spin_lock_irqsave(&l440gx_vpp_lock, flags);
  38         if (vpp) {
  39                 if (++l440gx_vpp_refcnt == 1)   /* first nested 'on' */
  40                         outl(inl(VPP_PORT) | 1, VPP_PORT);
  41         } else {
  42                 if (--l440gx_vpp_refcnt == 0)   /* last nested 'off' */
  43                         outl(inl(VPP_PORT) & ~1, VPP_PORT);
  44         }
  45         spin_unlock_irqrestore(&l440gx_vpp_lock, flags);
  46 }
  47
  48 static struct map_info l440gx_map = {
  49         .name = "L440GX BIOS",
  50         .size = WINDOW_SIZE,
  51         .bankwidth = BUSWIDTH,
  52         .phys = WINDOW_ADDR,
  53 #if 0
  54         /* FIXME verify that this is the
  55          * appripriate code for vpp enable/disable
  56          */
  57         .set_vpp = l440gx_set_vpp
  58 #endif
  59 };
  60
  61 static int __init init_l440gx(void)
  62 {
  63         struct pci_dev *dev, *pm_dev;
  64         struct resource *pm_iobase;
  65         __u16 word;
  66
  67         dev = pci_get_device(PCI_VENDOR_ID_INTEL,
  68                 PCI_DEVICE_ID_INTEL_82371AB_0, NULL);
  69
  70         pm_dev = pci_get_device(PCI_VENDOR_ID_INTEL,
  71                 PCI_DEVICE_ID_INTEL_82371AB_3, NULL);
  72
  73         pci_dev_put(dev);
  74
  75         if (!dev || !pm_dev) {
  76                 printk(KERN_NOTICE "L440GX flash mapping: failed to find PIIX4 ISA bridge, cannot continue\n");
  77                 pci_dev_put(pm_dev);
  78                 return -ENODEV;
  79         }
  80
  81         l440gx_map.virt = ioremap(WINDOW_ADDR, WINDOW_SIZE);
  82
  83         if (!l440gx_map.virt) {
  84                 printk(KERN_WARNING "Failed to ioremap L440GX flash region\n");
  85                 pci_dev_put(pm_dev);
  86                 return -ENOMEM;
  87         }
  88         simple_map_init(&l440gx_map);
  89         pr_debug("window_addr = %p\n", l440gx_map.virt);
  90
  91         /* Setup the pm iobase resource
  92          * This code should move into some kind of generic bridge
  93          * driver but for the moment I'm content with getting the
  94          * allocation correct.
  95          */
  96         pm_iobase = &pm_dev->resource[PIIXE_IOBASE_RESOURCE];
  97         if (!(pm_iobase->flags & IORESOURCE_IO)) {
  98                 pm_iobase->name = "pm iobase";
  99                 pm_iobase->start = 0;
 100                 pm_iobase->end = 63;
 101                 pm_iobase->flags = IORESOURCE_IO;
 102
 103                 /* Put the current value in the resource */
 104                 pci_read_config_dword(pm_dev, 0x40, &iobase);
 105                 iobase &= ~1;
 106                 pm_iobase->start += iobase & ~1;
 107                 pm_iobase->end += iobase & ~1;
 108
 109                 pci_dev_put(pm_dev);
 110
 111                 /* Allocate the resource region */
 112                 if (pci_assign_resource(pm_dev, PIIXE_IOBASE_RESOURCE) != 0) {
 113                         pci_dev_put(dev);
 114                         pci_dev_put(pm_dev);
 115                         printk(KERN_WARNING "Could not allocate pm iobase resource\n");
 116                         iounmap(l440gx_map.virt);
 117                         return -ENXIO;
 118                 }
 119         }
 120         /* Set the iobase */
 121         iobase = pm_iobase->start;
 122         pci_write_config_dword(pm_dev, 0x40, iobase | 1);
 123
 124
 125         /* Set XBCS# */
 126         pci_read_config_word(dev, 0x4e, &word);
 127         word |= 0x4;
 128         pci_write_config_word(dev, 0x4e, word);
 129
 130         /* Supply write voltage to the chip */
 131         l440gx_set_vpp(&l440gx_map, 1);
 132
 133         /* Enable the gate on the WE line */
 134         outb(inb(TRIBUF_PORT) & ~1, TRIBUF_PORT);
 135
 136         printk(KERN_NOTICE "Enabled WE line to L440GX BIOS flash chip.\n");
 137
 138         mymtd = do_map_probe("jedec_probe", &l440gx_map);
 139         if (!mymtd) {
 140                 printk(KERN_NOTICE "JEDEC probe on BIOS chip failed. Using ROM\n");
 141                 mymtd = do_map_probe("map_rom", &l440gx_map);
 142         }
 143         if (mymtd) {
 144                 mymtd->owner = THIS_MODULE;
 145
 146                 mtd_device_register(mymtd, NULL, 0);
 147                 return 0;
 148         }
 149
 150         iounmap(l440gx_map.virt);
 151         return -ENXIO;
 152 }
 153
 154 static void __exit cleanup_l440gx(void)
 155 {
 156         mtd_device_unregister(mymtd);
 157         map_destroy(mymtd);
 158
 159         iounmap(l440gx_map.virt);
 160 }
 161
 162 module_init(init_l440gx);
 163 module_exit(cleanup_l440gx);
 164
 165 MODULE_LICENSE("GPL");
 166 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
 167 MODULE_DESCRIPTION("MTD map driver for BIOS chips on Intel L440GX motherboards");