1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * This is a good place to put board specific reboot fixups.
4 *
5 * List of supported fixups:
6 * geode-gx1/cs5530a - Jaya Kumar <jayalk@intworks.biz>
7 * geode-gx/lx/cs5536 - Andres Salomon <dilinger@debian.org>
8 *
9 */
10
11 #include <asm/delay.h>
12 #include <linux/pci.h>
13 #include <linux/interrupt.h>
14 #include <asm/reboot_fixups.h>
15 #include <asm/msr.h>
16 #include <linux/cs5535.h>
17
cs5530a_warm_reset(struct pci_dev * dev)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
cs5536_warm_reset(struct pci_dev * dev)27 static void cs5536_warm_reset(struct pci_dev *dev)
28 {
29 /* writing 1 to the LSB of this MSR causes a hard reset */
30 wrmsrl(MSR_DIVIL_SOFT_RESET, 1ULL);
31 udelay(50); /* shouldn't get here but be safe and spin a while */
32 }
33
rdc321x_reset(struct pci_dev * dev)34 static void rdc321x_reset(struct pci_dev *dev)
35 {
36 unsigned i;
37 /* Voluntary reset the watchdog timer */
38 outl(0x80003840, 0xCF8);
39 /* Generate a CPU reset on next tick */
40 i = inl(0xCFC);
41 /* Use the minimum timer resolution */
42 i |= 0x1600;
43 outl(i, 0xCFC);
44 outb(1, 0x92);
45 }
46
ce4100_reset(struct pci_dev * dev)47 static void ce4100_reset(struct pci_dev *dev)
48 {
49 int i;
50
51 for (i = 0; i < 10; i++) {
52 outb(0x2, 0xcf9);
53 udelay(50);
54 }
55 }
56
57 struct device_fixup {
58 unsigned int vendor;
59 unsigned int device;
60 void (*reboot_fixup)(struct pci_dev *);
61 };
62
63 /*
64 * PCI ids solely used for fixups_table go here
65 */
66 #define PCI_DEVICE_ID_INTEL_CE4100 0x0708
67
68 static const struct device_fixup fixups_table[] = {
69 { PCI_VENDOR_ID_CYRIX, PCI_DEVICE_ID_CYRIX_5530_LEGACY, cs5530a_warm_reset },
70 { PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CS5536_ISA, cs5536_warm_reset },
71 { PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SC1100_BRIDGE, cs5530a_warm_reset },
72 { PCI_VENDOR_ID_RDC, PCI_DEVICE_ID_RDC_R6030, rdc321x_reset },
73 { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_CE4100, ce4100_reset },
74 };
75
76 /*
77 * we see if any fixup is available for our current hardware. if there
78 * is a fixup, we call it and we expect to never return from it. if we
79 * do return, we keep looking and then eventually fall back to the
80 * standard mach_reboot on return.
81 */
mach_reboot_fixups(void)82 void mach_reboot_fixups(void)
83 {
84 const struct device_fixup *cur;
85 struct pci_dev *dev;
86 int i;
87
88 /* we can be called from sysrq-B code. In such a case it is
89 * prohibited to dig PCI */
90 if (in_interrupt())
91 return;
92
93 for (i=0; i < ARRAY_SIZE(fixups_table); i++) {
94 cur = &(fixups_table[i]);
95 dev = pci_get_device(cur->vendor, cur->device, NULL);
96 if (!dev)
97 continue;
98
99 cur->reboot_fixup(dev);
100 pci_dev_put(dev);
101 }
102 }
103
104