Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6.git] / arch / x86 / kernel / vsmp_64.c
1 /*
2  * vSMPowered(tm) systems specific initialization
3  * Copyright (C) 2005 ScaleMP Inc.
4  *
5  * Use of this code is subject to the terms and conditions of the
6  * GNU general public license version 2. See "COPYING" or
7  * http://www.gnu.org/licenses/gpl.html
8  *
9  * Ravikiran Thirumalai <kiran@scalemp.com>,
10  * Shai Fultheim <shai@scalemp.com>
11  * Paravirt ops integration: Glauber de Oliveira Costa <gcosta@redhat.com>,
12  *                           Ravikiran Thirumalai <kiran@scalemp.com>
13  */
14
15 #include <linux/init.h>
16 #include <linux/pci_ids.h>
17 #include <linux/pci_regs.h>
18
19 #include <asm/apic.h>
20 #include <asm/pci-direct.h>
21 #include <asm/io.h>
22 #include <asm/paravirt.h>
23 #include <asm/setup.h>
24
25 #if defined CONFIG_PCI && defined CONFIG_PARAVIRT
26 /*
27  * Interrupt control on vSMPowered systems:
28  * ~AC is a shadow of IF.  If IF is 'on' AC should be 'off'
29  * and vice versa.
30  */
31
32 static unsigned long vsmp_save_fl(void)
33 {
34         unsigned long flags = native_save_fl();
35
36         if (!(flags & X86_EFLAGS_IF) || (flags & X86_EFLAGS_AC))
37                 flags &= ~X86_EFLAGS_IF;
38         return flags;
39 }
40
41 static void vsmp_restore_fl(unsigned long flags)
42 {
43         if (flags & X86_EFLAGS_IF)
44                 flags &= ~X86_EFLAGS_AC;
45         else
46                 flags |= X86_EFLAGS_AC;
47         native_restore_fl(flags);
48 }
49
50 static void vsmp_irq_disable(void)
51 {
52         unsigned long flags = native_save_fl();
53
54         native_restore_fl((flags & ~X86_EFLAGS_IF) | X86_EFLAGS_AC);
55 }
56
57 static void vsmp_irq_enable(void)
58 {
59         unsigned long flags = native_save_fl();
60
61         native_restore_fl((flags | X86_EFLAGS_IF) & (~X86_EFLAGS_AC));
62 }
63
64 static unsigned __init_or_module vsmp_patch(u8 type, u16 clobbers, void *ibuf,
65                                   unsigned long addr, unsigned len)
66 {
67         switch (type) {
68         case PARAVIRT_PATCH(pv_irq_ops.irq_enable):
69         case PARAVIRT_PATCH(pv_irq_ops.irq_disable):
70         case PARAVIRT_PATCH(pv_irq_ops.save_fl):
71         case PARAVIRT_PATCH(pv_irq_ops.restore_fl):
72                 return paravirt_patch_default(type, clobbers, ibuf, addr, len);
73         default:
74                 return native_patch(type, clobbers, ibuf, addr, len);
75         }
76
77 }
78
79 static void __init set_vsmp_pv_ops(void)
80 {
81         void *address;
82         unsigned int cap, ctl, cfg;
83
84         /* set vSMP magic bits to indicate vSMP capable kernel */
85         cfg = read_pci_config(0, 0x1f, 0, PCI_BASE_ADDRESS_0);
86         address = early_ioremap(cfg, 8);
87         cap = readl(address);
88         ctl = readl(address + 4);
89         printk(KERN_INFO "vSMP CTL: capabilities:0x%08x  control:0x%08x\n",
90                cap, ctl);
91         if (cap & ctl & (1 << 4)) {
92                 /* Setup irq ops and turn on vSMP  IRQ fastpath handling */
93                 pv_irq_ops.irq_disable = vsmp_irq_disable;
94                 pv_irq_ops.irq_enable  = vsmp_irq_enable;
95                 pv_irq_ops.save_fl  = vsmp_save_fl;
96                 pv_irq_ops.restore_fl  = vsmp_restore_fl;
97                 pv_init_ops.patch = vsmp_patch;
98
99                 ctl &= ~(1 << 4);
100                 writel(ctl, address + 4);
101                 ctl = readl(address + 4);
102                 printk(KERN_INFO "vSMP CTL: control set to:0x%08x\n", ctl);
103         }
104
105         early_iounmap(address, 8);
106 }
107 #else
108 static void __init set_vsmp_pv_ops(void)
109 {
110 }
111 #endif
112
113 #ifdef CONFIG_PCI
114 static int is_vsmp = -1;
115
116 static void __init detect_vsmp_box(void)
117 {
118         is_vsmp = 0;
119
120         if (!early_pci_allowed())
121                 return;
122
123         /* Check if we are running on a ScaleMP vSMPowered box */
124         if (read_pci_config(0, 0x1f, 0, PCI_VENDOR_ID) ==
125              (PCI_VENDOR_ID_SCALEMP | (PCI_DEVICE_ID_SCALEMP_VSMP_CTL << 16)))
126                 is_vsmp = 1;
127 }
128
129 int is_vsmp_box(void)
130 {
131         if (is_vsmp != -1)
132                 return is_vsmp;
133         else {
134                 WARN_ON_ONCE(1);
135                 return 0;
136         }
137 }
138 #else
139 static void __init detect_vsmp_box(void)
140 {
141 }
142 int is_vsmp_box(void)
143 {
144         return 0;
145 }
146 #endif
147
148 void __init vsmp_init(void)
149 {
150         detect_vsmp_box();
151         if (!is_vsmp_box())
152                 return;
153
154         set_vsmp_pv_ops();
155         return;
156 }