arch/x86/kernel/reboot_fixups_32.c

   1 /*
   2  * This is a good place to put board specific reboot fixups.
   3  *
   4  * List of supported fixups:
   5  * geode-gx1/cs5530a - Jaya Kumar <jayalk@intworks.biz>
   6  * geode-gx/lx/cs5536 - Andres Salomon <dilinger@debian.org>
   7  *
   8  */
   9
  10 #include <asm/delay.h>
  11 #include <linux/pci.h>
  12 #include <linux/interrupt.h>
  13 #include <asm/reboot_fixups.h>
  14 #include <asm/msr.h>
  15 #include <linux/cs5535.h>
  16
  17 static void cs5530a_warm_reset(struct pci_dev *dev)
  18 {
  19         /* writing 1 to the reset control register, 0x44 causes the
  20         cs5530a to perform a system warm reset */
  21         pci_write_config_byte(dev, 0x44, 0x1);
  22         udelay(50); /* shouldn't get here but be safe and spin-a-while */
  23         return;
  24 }
  25
  26 static void cs5536_warm_reset(struct pci_dev *dev)
  27 {
  28         /* writing 1 to the LSB of this MSR causes a hard reset */
  29         wrmsrl(MSR_DIVIL_SOFT_RESET, 1ULL);
  30         udelay(50); /* shouldn't get here but be safe and spin a while */
  31 }
  32
  33 static void rdc321x_reset(struct pci_dev *dev)
  34 {
  35         unsigned i;
  36         /* Voluntary reset the watchdog timer */
  37         outl(0x80003840, 0xCF8);
  38         /* Generate a CPU reset on next tick */
  39         i = inl(0xCFC);
  40         /* Use the minimum timer resolution */
  41         i |= 0x1600;
  42         outl(i, 0xCFC);
  43         outb(1, 0x92);
  44 }
  45
  46 struct device_fixup {
  47         unsigned int vendor;
  48         unsigned int device;
  49         void (*reboot_fixup)(struct pci_dev *);
  50 };
  51
  52 static const struct device_fixup fixups_table[] = {
  53 { PCI_VENDOR_ID_CYRIX, PCI_DEVICE_ID_CYRIX_5530_LEGACY, cs5530a_warm_reset },
  54 { PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CS5536_ISA, cs5536_warm_reset },
  55 { PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SC1100_BRIDGE, cs5530a_warm_reset },
  56 { PCI_VENDOR_ID_RDC, PCI_DEVICE_ID_RDC_R6030, rdc321x_reset },
  57 };
  58
  59 /*
  60  * we see if any fixup is available for our current hardware. if there
  61  * is a fixup, we call it and we expect to never return from it. if we
  62  * do return, we keep looking and then eventually fall back to the
  63  * standard mach_reboot on return.
  64  */
  65 void mach_reboot_fixups(void)
  66 {
  67         const struct device_fixup *cur;
  68         struct pci_dev *dev;
  69         int i;
  70
  71         /* we can be called from sysrq-B code. In such a case it is
  72          * prohibited to dig PCI */
  73         if (in_interrupt())
  74                 return;
  75
  76         for (i=0; i < ARRAY_SIZE(fixups_table); i++) {
  77                 cur = &(fixups_table[i]);
  78                 dev = pci_get_device(cur->vendor, cur->device, NULL);
  79                 if (!dev)
  80                         continue;
  81
  82                 cur->reboot_fixup(dev);
  83                 pci_dev_put(dev);
  84         }
  85 }
  86