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 <asm/geode.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 struct device_fixup {
34 	unsigned int vendor;
35 	unsigned int device;
36 	void (*reboot_fixup)(struct pci_dev *);
37 };
38 
39 static struct device_fixup fixups_table[] = {
40 { PCI_VENDOR_ID_CYRIX, PCI_DEVICE_ID_CYRIX_5530_LEGACY, cs5530a_warm_reset },
41 { PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CS5536_ISA, cs5536_warm_reset },
42 { PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SC1100_BRIDGE, cs5530a_warm_reset },
43 };
44 
45 /*
46  * we see if any fixup is available for our current hardware. if there
47  * is a fixup, we call it and we expect to never return from it. if we
48  * do return, we keep looking and then eventually fall back to the
49  * standard mach_reboot on return.
50  */
51 void mach_reboot_fixups(void)
52 {
53 	struct device_fixup *cur;
54 	struct pci_dev *dev;
55 	int i;
56 
57 	/* we can be called from sysrq-B code. In such a case it is
58 	 * prohibited to dig PCI */
59 	if (in_interrupt())
60 		return;
61 
62 	for (i=0; i < ARRAY_SIZE(fixups_table); i++) {
63 		cur = &(fixups_table[i]);
64 		dev = pci_get_device(cur->vendor, cur->device, NULL);
65 		if (!dev)
66 			continue;
67 
68 		cur->reboot_fixup(dev);
69 	}
70 }
71 
72