1 /* 2 * linux/arch/i386/kernel/reboot_fixups.c 3 * 4 * This is a good place to put board specific reboot fixups. 5 * 6 * List of supported fixups: 7 * geode-gx1/cs5530a - Jaya Kumar <jayalk@intworks.biz> 8 * geode-gx/lx/cs5536 - Andres Salomon <dilinger@debian.org> 9 * 10 */ 11 12 #include <asm/delay.h> 13 #include <linux/pci.h> 14 #include <linux/interrupt.h> 15 #include <asm/reboot_fixups.h> 16 #include <asm/msr.h> 17 18 static void cs5530a_warm_reset(struct pci_dev *dev) 19 { 20 /* writing 1 to the reset control register, 0x44 causes the 21 cs5530a to perform a system warm reset */ 22 pci_write_config_byte(dev, 0x44, 0x1); 23 udelay(50); /* shouldn't get here but be safe and spin-a-while */ 24 return; 25 } 26 27 static void cs5536_warm_reset(struct pci_dev *dev) 28 { 29 /* 30 * 6.6.2.12 Soft Reset (DIVIL_SOFT_RESET) 31 * writing 1 to the LSB of this MSR causes a hard reset. 32 */ 33 wrmsrl(0x51400017, 1ULL); 34 udelay(50); /* shouldn't get here but be safe and spin a while */ 35 } 36 37 struct device_fixup { 38 unsigned int vendor; 39 unsigned int device; 40 void (*reboot_fixup)(struct pci_dev *); 41 }; 42 43 static struct device_fixup fixups_table[] = { 44 { PCI_VENDOR_ID_CYRIX, PCI_DEVICE_ID_CYRIX_5530_LEGACY, cs5530a_warm_reset }, 45 { PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CS5536_ISA, cs5536_warm_reset }, 46 }; 47 48 /* 49 * we see if any fixup is available for our current hardware. if there 50 * is a fixup, we call it and we expect to never return from it. if we 51 * do return, we keep looking and then eventually fall back to the 52 * standard mach_reboot on return. 53 */ 54 void mach_reboot_fixups(void) 55 { 56 struct device_fixup *cur; 57 struct pci_dev *dev; 58 int i; 59 60 /* we can be called from sysrq-B code. In such a case it is 61 * prohibited to dig PCI */ 62 if (in_interrupt()) 63 return; 64 65 for (i=0; i < ARRAY_SIZE(fixups_table); i++) { 66 cur = &(fixups_table[i]); 67 dev = pci_get_device(cur->vendor, cur->device, NULL); 68 if (!dev) 69 continue; 70 71 cur->reboot_fixup(dev); 72 } 73 } 74 75