Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
[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 PV_CALLEE_SAVE_REGS_THUNK(vsmp_save_fl);
41
42 static void vsmp_restore_fl(unsigned long flags)
43 {
44         if (flags & X86_EFLAGS_IF)
45                 flags &= ~X86_EFLAGS_AC;
46         else
47                 flags |= X86_EFLAGS_AC;
48         native_restore_fl(flags);
49 }
50 PV_CALLEE_SAVE_REGS_THUNK(vsmp_restore_fl);
51
52 static void vsmp_irq_disable(void)
53 {
54         unsigned long flags = native_save_fl();
55
56         native_restore_fl((flags & ~X86_EFLAGS_IF) | X86_EFLAGS_AC);
57 }
58 PV_CALLEE_SAVE_REGS_THUNK(vsmp_irq_disable);
59
60 static void vsmp_irq_enable(void)
61 {
62         unsigned long flags = native_save_fl();
63
64         native_restore_fl((flags | X86_EFLAGS_IF) & (~X86_EFLAGS_AC));
65 }
66 PV_CALLEE_SAVE_REGS_THUNK(vsmp_irq_enable);
67
68 static unsigned __init_or_module vsmp_patch(u8 type, u16 clobbers, void *ibuf,
69                                   unsigned long addr, unsigned len)
70 {
71         switch (type) {
72         case PARAVIRT_PATCH(pv_irq_ops.irq_enable):
73         case PARAVIRT_PATCH(pv_irq_ops.irq_disable):
74         case PARAVIRT_PATCH(pv_irq_ops.save_fl):
75         case PARAVIRT_PATCH(pv_irq_ops.restore_fl):
76                 return paravirt_patch_default(type, clobbers, ibuf, addr, len);
77         default:
78                 return native_patch(type, clobbers, ibuf, addr, len);
79         }
80
81 }
82
83 static void __init set_vsmp_pv_ops(void)
84 {
85         void __iomem *address;
86         unsigned int cap, ctl, cfg;
87
88         /* set vSMP magic bits to indicate vSMP capable kernel */
89         cfg = read_pci_config(0, 0x1f, 0, PCI_BASE_ADDRESS_0);
90         address = early_ioremap(cfg, 8);
91         cap = readl(address);
92         ctl = readl(address + 4);
93         printk(KERN_INFO "vSMP CTL: capabilities:0x%08x  control:0x%08x\n",
94                cap, ctl);
95         if (cap & ctl & (1 << 4)) {
96                 /* Setup irq ops and turn on vSMP  IRQ fastpath handling */
97                 pv_irq_ops.irq_disable = PV_CALLEE_SAVE(vsmp_irq_disable);
98                 pv_irq_ops.irq_enable  = PV_CALLEE_SAVE(vsmp_irq_enable);
99                 pv_irq_ops.save_fl  = PV_CALLEE_SAVE(vsmp_save_fl);
100                 pv_irq_ops.restore_fl  = PV_CALLEE_SAVE(vsmp_restore_fl);
101                 pv_init_ops.patch = vsmp_patch;
102
103                 ctl &= ~(1 << 4);
104                 writel(ctl, address + 4);
105                 ctl = readl(address + 4);
106                 printk(KERN_INFO "vSMP CTL: control set to:0x%08x\n", ctl);
107         }
108
109         early_iounmap(address, 8);
110 }
111 #else
112 static void __init set_vsmp_pv_ops(void)
113 {
114 }
115 #endif
116
117 #ifdef CONFIG_PCI
118 static int is_vsmp = -1;
119
120 static void __init detect_vsmp_box(void)
121 {
122         is_vsmp = 0;
123
124         if (!early_pci_allowed())
125                 return;
126
127         /* Check if we are running on a ScaleMP vSMPowered box */
128         if (read_pci_config(0, 0x1f, 0, PCI_VENDOR_ID) ==
129              (PCI_VENDOR_ID_SCALEMP | (PCI_DEVICE_ID_SCALEMP_VSMP_CTL << 16)))
130                 is_vsmp = 1;
131 }
132
133 int is_vsmp_box(void)
134 {
135         if (is_vsmp != -1)
136                 return is_vsmp;
137         else {
138                 WARN_ON_ONCE(1);
139                 return 0;
140         }
141 }
142
143 #else
144 static void __init detect_vsmp_box(void)
145 {
146 }
147 int is_vsmp_box(void)
148 {
149         return 0;
150 }
151 #endif
152 void __init vsmp_init(void)
153 {
154         detect_vsmp_box();
155         if (!is_vsmp_box())
156                 return;
157
158         set_vsmp_pv_ops();
159         return;
160 }