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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * vSMPowered(tm) systems specific initialization
4 * Copyright (C) 2005 ScaleMP Inc.
5 *
6 * Ravikiran Thirumalai <kiran@scalemp.com>,
7 * Shai Fultheim <shai@scalemp.com>
8 * Paravirt ops integration: Glauber de Oliveira Costa <gcosta@redhat.com>,
9 * Ravikiran Thirumalai <kiran@scalemp.com>
10 */
11
12#include <linux/init.h>
13#include <linux/pci_ids.h>
14#include <linux/pci_regs.h>
15#include <linux/smp.h>
16#include <linux/irq.h>
17
18#include <asm/apic.h>
19#include <asm/pci-direct.h>
20#include <asm/io.h>
21#include <asm/paravirt.h>
22#include <asm/setup.h>
23
24#define TOPOLOGY_REGISTER_OFFSET 0x10
25
26#ifdef CONFIG_PCI
27static void __init set_vsmp_ctl(void)
28{
29 void __iomem *address;
30 unsigned int cap, ctl, cfg;
31
32 /* set vSMP magic bits to indicate vSMP capable kernel */
33 cfg = read_pci_config(0, 0x1f, 0, PCI_BASE_ADDRESS_0);
34 address = early_ioremap(cfg, 8);
35 cap = readl(address);
36 ctl = readl(address + 4);
37 printk(KERN_INFO "vSMP CTL: capabilities:0x%08x control:0x%08x\n",
38 cap, ctl);
39
40 /* If possible, let the vSMP foundation route the interrupt optimally */
41#ifdef CONFIG_SMP
42 if (cap & ctl & BIT(8)) {
43 ctl &= ~BIT(8);
44
45#ifdef CONFIG_PROC_FS
46 /* Don't let users change irq affinity via procfs */
47 no_irq_affinity = 1;
48#endif
49 }
50#endif
51
52 writel(ctl, address + 4);
53 ctl = readl(address + 4);
54 pr_info("vSMP CTL: control set to:0x%08x\n", ctl);
55
56 early_iounmap(address, 8);
57}
58static int is_vsmp = -1;
59
60static void __init detect_vsmp_box(void)
61{
62 is_vsmp = 0;
63
64 if (!early_pci_allowed())
65 return;
66
67 /* Check if we are running on a ScaleMP vSMPowered box */
68 if (read_pci_config(0, 0x1f, 0, PCI_VENDOR_ID) ==
69 (PCI_VENDOR_ID_SCALEMP | (PCI_DEVICE_ID_SCALEMP_VSMP_CTL << 16)))
70 is_vsmp = 1;
71}
72
73static int is_vsmp_box(void)
74{
75 if (is_vsmp != -1)
76 return is_vsmp;
77 else {
78 WARN_ON_ONCE(1);
79 return 0;
80 }
81}
82
83#else
84static void __init detect_vsmp_box(void)
85{
86}
87static int is_vsmp_box(void)
88{
89 return 0;
90}
91static void __init set_vsmp_ctl(void)
92{
93}
94#endif
95
96static void __init vsmp_cap_cpus(void)
97{
98#if !defined(CONFIG_X86_VSMP) && defined(CONFIG_SMP) && defined(CONFIG_PCI)
99 void __iomem *address;
100 unsigned int cfg, topology, node_shift, maxcpus;
101
102 /*
103 * CONFIG_X86_VSMP is not configured, so limit the number CPUs to the
104 * ones present in the first board, unless explicitly overridden by
105 * setup_max_cpus
106 */
107 if (setup_max_cpus != NR_CPUS)
108 return;
109
110 /* Read the vSMP Foundation topology register */
111 cfg = read_pci_config(0, 0x1f, 0, PCI_BASE_ADDRESS_0);
112 address = early_ioremap(cfg + TOPOLOGY_REGISTER_OFFSET, 4);
113 if (WARN_ON(!address))
114 return;
115
116 topology = readl(address);
117 node_shift = (topology >> 16) & 0x7;
118 if (!node_shift)
119 /* The value 0 should be decoded as 8 */
120 node_shift = 8;
121 maxcpus = (topology & ((1 << node_shift) - 1)) + 1;
122
123 pr_info("vSMP CTL: Capping CPUs to %d (CONFIG_X86_VSMP is unset)\n",
124 maxcpus);
125 setup_max_cpus = maxcpus;
126 early_iounmap(address, 4);
127#endif
128}
129
130void __init vsmp_init(void)
131{
132 detect_vsmp_box();
133 if (!is_vsmp_box())
134 return;
135
136 vsmp_cap_cpus();
137
138 set_vsmp_ctl();
139 return;
140}
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#include <linux/smp.h>
19
20#include <asm/apic.h>
21#include <asm/pci-direct.h>
22#include <asm/io.h>
23#include <asm/paravirt.h>
24#include <asm/setup.h>
25
26#define TOPOLOGY_REGISTER_OFFSET 0x10
27
28#if defined CONFIG_PCI && defined CONFIG_PARAVIRT
29/*
30 * Interrupt control on vSMPowered systems:
31 * ~AC is a shadow of IF. If IF is 'on' AC should be 'off'
32 * and vice versa.
33 */
34
35static unsigned long vsmp_save_fl(void)
36{
37 unsigned long flags = native_save_fl();
38
39 if (!(flags & X86_EFLAGS_IF) || (flags & X86_EFLAGS_AC))
40 flags &= ~X86_EFLAGS_IF;
41 return flags;
42}
43PV_CALLEE_SAVE_REGS_THUNK(vsmp_save_fl);
44
45static void vsmp_restore_fl(unsigned long flags)
46{
47 if (flags & X86_EFLAGS_IF)
48 flags &= ~X86_EFLAGS_AC;
49 else
50 flags |= X86_EFLAGS_AC;
51 native_restore_fl(flags);
52}
53PV_CALLEE_SAVE_REGS_THUNK(vsmp_restore_fl);
54
55static void vsmp_irq_disable(void)
56{
57 unsigned long flags = native_save_fl();
58
59 native_restore_fl((flags & ~X86_EFLAGS_IF) | X86_EFLAGS_AC);
60}
61PV_CALLEE_SAVE_REGS_THUNK(vsmp_irq_disable);
62
63static void vsmp_irq_enable(void)
64{
65 unsigned long flags = native_save_fl();
66
67 native_restore_fl((flags | X86_EFLAGS_IF) & (~X86_EFLAGS_AC));
68}
69PV_CALLEE_SAVE_REGS_THUNK(vsmp_irq_enable);
70
71static unsigned __init_or_module vsmp_patch(u8 type, u16 clobbers, void *ibuf,
72 unsigned long addr, unsigned len)
73{
74 switch (type) {
75 case PARAVIRT_PATCH(pv_irq_ops.irq_enable):
76 case PARAVIRT_PATCH(pv_irq_ops.irq_disable):
77 case PARAVIRT_PATCH(pv_irq_ops.save_fl):
78 case PARAVIRT_PATCH(pv_irq_ops.restore_fl):
79 return paravirt_patch_default(type, clobbers, ibuf, addr, len);
80 default:
81 return native_patch(type, clobbers, ibuf, addr, len);
82 }
83
84}
85
86static void __init set_vsmp_pv_ops(void)
87{
88 void __iomem *address;
89 unsigned int cap, ctl, cfg;
90
91 /* set vSMP magic bits to indicate vSMP capable kernel */
92 cfg = read_pci_config(0, 0x1f, 0, PCI_BASE_ADDRESS_0);
93 address = early_ioremap(cfg, 8);
94 cap = readl(address);
95 ctl = readl(address + 4);
96 printk(KERN_INFO "vSMP CTL: capabilities:0x%08x control:0x%08x\n",
97 cap, ctl);
98 if (cap & ctl & (1 << 4)) {
99 /* Setup irq ops and turn on vSMP IRQ fastpath handling */
100 pv_irq_ops.irq_disable = PV_CALLEE_SAVE(vsmp_irq_disable);
101 pv_irq_ops.irq_enable = PV_CALLEE_SAVE(vsmp_irq_enable);
102 pv_irq_ops.save_fl = PV_CALLEE_SAVE(vsmp_save_fl);
103 pv_irq_ops.restore_fl = PV_CALLEE_SAVE(vsmp_restore_fl);
104 pv_init_ops.patch = vsmp_patch;
105
106 ctl &= ~(1 << 4);
107 writel(ctl, address + 4);
108 ctl = readl(address + 4);
109 printk(KERN_INFO "vSMP CTL: control set to:0x%08x\n", ctl);
110 }
111
112 early_iounmap(address, 8);
113}
114#else
115static void __init set_vsmp_pv_ops(void)
116{
117}
118#endif
119
120#ifdef CONFIG_PCI
121static int is_vsmp = -1;
122
123static void __init detect_vsmp_box(void)
124{
125 is_vsmp = 0;
126
127 if (!early_pci_allowed())
128 return;
129
130 /* Check if we are running on a ScaleMP vSMPowered box */
131 if (read_pci_config(0, 0x1f, 0, PCI_VENDOR_ID) ==
132 (PCI_VENDOR_ID_SCALEMP | (PCI_DEVICE_ID_SCALEMP_VSMP_CTL << 16)))
133 is_vsmp = 1;
134}
135
136int is_vsmp_box(void)
137{
138 if (is_vsmp != -1)
139 return is_vsmp;
140 else {
141 WARN_ON_ONCE(1);
142 return 0;
143 }
144}
145
146#else
147static void __init detect_vsmp_box(void)
148{
149}
150int is_vsmp_box(void)
151{
152 return 0;
153}
154#endif
155
156static void __init vsmp_cap_cpus(void)
157{
158#if !defined(CONFIG_X86_VSMP) && defined(CONFIG_SMP)
159 void __iomem *address;
160 unsigned int cfg, topology, node_shift, maxcpus;
161
162 /*
163 * CONFIG_X86_VSMP is not configured, so limit the number CPUs to the
164 * ones present in the first board, unless explicitly overridden by
165 * setup_max_cpus
166 */
167 if (setup_max_cpus != NR_CPUS)
168 return;
169
170 /* Read the vSMP Foundation topology register */
171 cfg = read_pci_config(0, 0x1f, 0, PCI_BASE_ADDRESS_0);
172 address = early_ioremap(cfg + TOPOLOGY_REGISTER_OFFSET, 4);
173 if (WARN_ON(!address))
174 return;
175
176 topology = readl(address);
177 node_shift = (topology >> 16) & 0x7;
178 if (!node_shift)
179 /* The value 0 should be decoded as 8 */
180 node_shift = 8;
181 maxcpus = (topology & ((1 << node_shift) - 1)) + 1;
182
183 pr_info("vSMP CTL: Capping CPUs to %d (CONFIG_X86_VSMP is unset)\n",
184 maxcpus);
185 setup_max_cpus = maxcpus;
186 early_iounmap(address, 4);
187#endif
188}
189
190void __init vsmp_init(void)
191{
192 detect_vsmp_box();
193 if (!is_vsmp_box())
194 return;
195
196 vsmp_cap_cpus();
197
198 set_vsmp_pv_ops();
199 return;
200}