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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
130static int apicid_phys_pkg_id(int initial_apic_id, int index_msb)
131{
132 return hard_smp_processor_id() >> index_msb;
133}
134
135static void vsmp_apic_post_init(void)
136{
137 /* need to update phys_pkg_id */
138 apic->phys_pkg_id = apicid_phys_pkg_id;
139}
140
141void __init vsmp_init(void)
142{
143 detect_vsmp_box();
144 if (!is_vsmp_box())
145 return;
146
147 x86_platform.apic_post_init = vsmp_apic_post_init;
148
149 vsmp_cap_cpus();
150
151 set_vsmp_ctl();
152 return;
153}
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#include <linux/irq.h>
20
21#include <asm/apic.h>
22#include <asm/pci-direct.h>
23#include <asm/io.h>
24#include <asm/paravirt.h>
25#include <asm/setup.h>
26
27#define TOPOLOGY_REGISTER_OFFSET 0x10
28
29/* Flag below is initialized once during vSMP PCI initialization. */
30static int irq_routing_comply = 1;
31
32#if defined CONFIG_PCI && defined CONFIG_PARAVIRT
33/*
34 * Interrupt control on vSMPowered systems:
35 * ~AC is a shadow of IF. If IF is 'on' AC should be 'off'
36 * and vice versa.
37 */
38
39asmlinkage __visible unsigned long vsmp_save_fl(void)
40{
41 unsigned long flags = native_save_fl();
42
43 if (!(flags & X86_EFLAGS_IF) || (flags & X86_EFLAGS_AC))
44 flags &= ~X86_EFLAGS_IF;
45 return flags;
46}
47PV_CALLEE_SAVE_REGS_THUNK(vsmp_save_fl);
48
49__visible void vsmp_restore_fl(unsigned long flags)
50{
51 if (flags & X86_EFLAGS_IF)
52 flags &= ~X86_EFLAGS_AC;
53 else
54 flags |= X86_EFLAGS_AC;
55 native_restore_fl(flags);
56}
57PV_CALLEE_SAVE_REGS_THUNK(vsmp_restore_fl);
58
59asmlinkage __visible void vsmp_irq_disable(void)
60{
61 unsigned long flags = native_save_fl();
62
63 native_restore_fl((flags & ~X86_EFLAGS_IF) | X86_EFLAGS_AC);
64}
65PV_CALLEE_SAVE_REGS_THUNK(vsmp_irq_disable);
66
67asmlinkage __visible void vsmp_irq_enable(void)
68{
69 unsigned long flags = native_save_fl();
70
71 native_restore_fl((flags | X86_EFLAGS_IF) & (~X86_EFLAGS_AC));
72}
73PV_CALLEE_SAVE_REGS_THUNK(vsmp_irq_enable);
74
75static unsigned __init vsmp_patch(u8 type, u16 clobbers, void *ibuf,
76 unsigned long addr, unsigned len)
77{
78 switch (type) {
79 case PARAVIRT_PATCH(pv_irq_ops.irq_enable):
80 case PARAVIRT_PATCH(pv_irq_ops.irq_disable):
81 case PARAVIRT_PATCH(pv_irq_ops.save_fl):
82 case PARAVIRT_PATCH(pv_irq_ops.restore_fl):
83 return paravirt_patch_default(type, clobbers, ibuf, addr, len);
84 default:
85 return native_patch(type, clobbers, ibuf, addr, len);
86 }
87
88}
89
90static void __init set_vsmp_pv_ops(void)
91{
92 void __iomem *address;
93 unsigned int cap, ctl, cfg;
94
95 /* set vSMP magic bits to indicate vSMP capable kernel */
96 cfg = read_pci_config(0, 0x1f, 0, PCI_BASE_ADDRESS_0);
97 address = early_ioremap(cfg, 8);
98 cap = readl(address);
99 ctl = readl(address + 4);
100 printk(KERN_INFO "vSMP CTL: capabilities:0x%08x control:0x%08x\n",
101 cap, ctl);
102
103 /* If possible, let the vSMP foundation route the interrupt optimally */
104#ifdef CONFIG_SMP
105 if (cap & ctl & BIT(8)) {
106 ctl &= ~BIT(8);
107
108 /* Interrupt routing set to ignore */
109 irq_routing_comply = 0;
110
111#ifdef CONFIG_PROC_FS
112 /* Don't let users change irq affinity via procfs */
113 no_irq_affinity = 1;
114#endif
115 }
116#endif
117
118 if (cap & ctl & (1 << 4)) {
119 /* Setup irq ops and turn on vSMP IRQ fastpath handling */
120 pv_irq_ops.irq_disable = PV_CALLEE_SAVE(vsmp_irq_disable);
121 pv_irq_ops.irq_enable = PV_CALLEE_SAVE(vsmp_irq_enable);
122 pv_irq_ops.save_fl = PV_CALLEE_SAVE(vsmp_save_fl);
123 pv_irq_ops.restore_fl = PV_CALLEE_SAVE(vsmp_restore_fl);
124 pv_init_ops.patch = vsmp_patch;
125 ctl &= ~(1 << 4);
126 }
127 writel(ctl, address + 4);
128 ctl = readl(address + 4);
129 pr_info("vSMP CTL: control set to:0x%08x\n", ctl);
130
131 early_iounmap(address, 8);
132}
133#else
134static void __init set_vsmp_pv_ops(void)
135{
136}
137#endif
138
139#ifdef CONFIG_PCI
140static int is_vsmp = -1;
141
142static void __init detect_vsmp_box(void)
143{
144 is_vsmp = 0;
145
146 if (!early_pci_allowed())
147 return;
148
149 /* Check if we are running on a ScaleMP vSMPowered box */
150 if (read_pci_config(0, 0x1f, 0, PCI_VENDOR_ID) ==
151 (PCI_VENDOR_ID_SCALEMP | (PCI_DEVICE_ID_SCALEMP_VSMP_CTL << 16)))
152 is_vsmp = 1;
153}
154
155static int is_vsmp_box(void)
156{
157 if (is_vsmp != -1)
158 return is_vsmp;
159 else {
160 WARN_ON_ONCE(1);
161 return 0;
162 }
163}
164
165#else
166static void __init detect_vsmp_box(void)
167{
168}
169static int is_vsmp_box(void)
170{
171 return 0;
172}
173#endif
174
175static void __init vsmp_cap_cpus(void)
176{
177#if !defined(CONFIG_X86_VSMP) && defined(CONFIG_SMP)
178 void __iomem *address;
179 unsigned int cfg, topology, node_shift, maxcpus;
180
181 /*
182 * CONFIG_X86_VSMP is not configured, so limit the number CPUs to the
183 * ones present in the first board, unless explicitly overridden by
184 * setup_max_cpus
185 */
186 if (setup_max_cpus != NR_CPUS)
187 return;
188
189 /* Read the vSMP Foundation topology register */
190 cfg = read_pci_config(0, 0x1f, 0, PCI_BASE_ADDRESS_0);
191 address = early_ioremap(cfg + TOPOLOGY_REGISTER_OFFSET, 4);
192 if (WARN_ON(!address))
193 return;
194
195 topology = readl(address);
196 node_shift = (topology >> 16) & 0x7;
197 if (!node_shift)
198 /* The value 0 should be decoded as 8 */
199 node_shift = 8;
200 maxcpus = (topology & ((1 << node_shift) - 1)) + 1;
201
202 pr_info("vSMP CTL: Capping CPUs to %d (CONFIG_X86_VSMP is unset)\n",
203 maxcpus);
204 setup_max_cpus = maxcpus;
205 early_iounmap(address, 4);
206#endif
207}
208
209static int apicid_phys_pkg_id(int initial_apic_id, int index_msb)
210{
211 return hard_smp_processor_id() >> index_msb;
212}
213
214/*
215 * In vSMP, all cpus should be capable of handling interrupts, regardless of
216 * the APIC used.
217 */
218static void fill_vector_allocation_domain(int cpu, struct cpumask *retmask,
219 const struct cpumask *mask)
220{
221 cpumask_setall(retmask);
222}
223
224static void vsmp_apic_post_init(void)
225{
226 /* need to update phys_pkg_id */
227 apic->phys_pkg_id = apicid_phys_pkg_id;
228
229 if (!irq_routing_comply)
230 apic->vector_allocation_domain = fill_vector_allocation_domain;
231}
232
233void __init vsmp_init(void)
234{
235 detect_vsmp_box();
236 if (!is_vsmp_box())
237 return;
238
239 x86_platform.apic_post_init = vsmp_apic_post_init;
240
241 vsmp_cap_cpus();
242
243 set_vsmp_pv_ops();
244 return;
245}