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  • only in /asuswrt-rt-n18u-9.0.0.4.380.2695/release/src-rt-6.x.4708/linux/linux-2.6.36/arch/x86/kernel/
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
32static 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}
40PV_CALLEE_SAVE_REGS_THUNK(vsmp_save_fl);
41
42static 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}
50PV_CALLEE_SAVE_REGS_THUNK(vsmp_restore_fl);
51
52static 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}
58PV_CALLEE_SAVE_REGS_THUNK(vsmp_irq_disable);
59
60static 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}
66PV_CALLEE_SAVE_REGS_THUNK(vsmp_irq_enable);
67
68static 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
83static 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
112static void __init set_vsmp_pv_ops(void)
113{
114}
115#endif
116
117#ifdef CONFIG_PCI
118static int is_vsmp = -1;
119
120static 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
133int 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
144static void __init detect_vsmp_box(void)
145{
146}
147int is_vsmp_box(void)
148{
149	return 0;
150}
151#endif
152void __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}
161