xref: /openbmc/linux/arch/x86/kernel/apic/bigsmp_32.c (revision 141d3b1d)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * APIC driver for "bigsmp" xAPIC machines with more than 8 virtual CPUs.
4  *
5  * Drives the local APIC in "clustered mode".
6  */
7 #include <linux/threads.h>
8 #include <linux/cpumask.h>
9 #include <linux/kernel.h>
10 #include <linux/init.h>
11 #include <linux/dmi.h>
12 #include <linux/smp.h>
13 
14 #include <asm/apicdef.h>
15 #include <asm/fixmap.h>
16 #include <asm/mpspec.h>
17 #include <asm/apic.h>
18 #include <asm/ipi.h>
19 
20 static unsigned bigsmp_get_apic_id(unsigned long x)
21 {
22 	return (x >> 24) & 0xFF;
23 }
24 
25 static int bigsmp_apic_id_registered(void)
26 {
27 	return 1;
28 }
29 
30 static bool bigsmp_check_apicid_used(physid_mask_t *map, int apicid)
31 {
32 	return false;
33 }
34 
35 static int bigsmp_early_logical_apicid(int cpu)
36 {
37 	/* on bigsmp, logical apicid is the same as physical */
38 	return early_per_cpu(x86_cpu_to_apicid, cpu);
39 }
40 
41 static inline unsigned long calculate_ldr(int cpu)
42 {
43 	unsigned long val, id;
44 
45 	val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
46 	id = per_cpu(x86_bios_cpu_apicid, cpu);
47 	val |= SET_APIC_LOGICAL_ID(id);
48 
49 	return val;
50 }
51 
52 /*
53  * Set up the logical destination ID.
54  *
55  * Intel recommends to set DFR, LDR and TPR before enabling
56  * an APIC.  See e.g. "AP-388 82489DX User's Manual" (Intel
57  * document number 292116).  So here it goes...
58  */
59 static void bigsmp_init_apic_ldr(void)
60 {
61 	unsigned long val;
62 	int cpu = smp_processor_id();
63 
64 	apic_write(APIC_DFR, APIC_DFR_FLAT);
65 	val = calculate_ldr(cpu);
66 	apic_write(APIC_LDR, val);
67 }
68 
69 static void bigsmp_setup_apic_routing(void)
70 {
71 	printk(KERN_INFO
72 		"Enabling APIC mode:  Physflat.  Using %d I/O APICs\n",
73 		nr_ioapics);
74 }
75 
76 static int bigsmp_cpu_present_to_apicid(int mps_cpu)
77 {
78 	if (mps_cpu < nr_cpu_ids)
79 		return (int) per_cpu(x86_bios_cpu_apicid, mps_cpu);
80 
81 	return BAD_APICID;
82 }
83 
84 static void bigsmp_ioapic_phys_id_map(physid_mask_t *phys_map, physid_mask_t *retmap)
85 {
86 	/* For clustered we don't have a good way to do this yet - hack */
87 	physids_promote(0xFFL, retmap);
88 }
89 
90 static int bigsmp_check_phys_apicid_present(int phys_apicid)
91 {
92 	return 1;
93 }
94 
95 static int bigsmp_phys_pkg_id(int cpuid_apic, int index_msb)
96 {
97 	return cpuid_apic >> index_msb;
98 }
99 
100 static void bigsmp_send_IPI_allbutself(int vector)
101 {
102 	default_send_IPI_mask_allbutself_phys(cpu_online_mask, vector);
103 }
104 
105 static void bigsmp_send_IPI_all(int vector)
106 {
107 	default_send_IPI_mask_sequence_phys(cpu_online_mask, vector);
108 }
109 
110 static int dmi_bigsmp; /* can be set by dmi scanners */
111 
112 static int hp_ht_bigsmp(const struct dmi_system_id *d)
113 {
114 	printk(KERN_NOTICE "%s detected: force use of apic=bigsmp\n", d->ident);
115 	dmi_bigsmp = 1;
116 
117 	return 0;
118 }
119 
120 
121 static const struct dmi_system_id bigsmp_dmi_table[] = {
122 	{ hp_ht_bigsmp, "HP ProLiant DL760 G2",
123 		{	DMI_MATCH(DMI_BIOS_VENDOR, "HP"),
124 			DMI_MATCH(DMI_BIOS_VERSION, "P44-"),
125 		}
126 	},
127 
128 	{ hp_ht_bigsmp, "HP ProLiant DL740",
129 		{	DMI_MATCH(DMI_BIOS_VENDOR, "HP"),
130 			DMI_MATCH(DMI_BIOS_VERSION, "P47-"),
131 		}
132 	},
133 	{ } /* NULL entry stops DMI scanning */
134 };
135 
136 static int probe_bigsmp(void)
137 {
138 	if (def_to_bigsmp)
139 		dmi_bigsmp = 1;
140 	else
141 		dmi_check_system(bigsmp_dmi_table);
142 
143 	return dmi_bigsmp;
144 }
145 
146 static struct apic apic_bigsmp __ro_after_init = {
147 
148 	.name				= "bigsmp",
149 	.probe				= probe_bigsmp,
150 	.acpi_madt_oem_check		= NULL,
151 	.apic_id_valid			= default_apic_id_valid,
152 	.apic_id_registered		= bigsmp_apic_id_registered,
153 
154 	.irq_delivery_mode		= dest_Fixed,
155 	/* phys delivery to target CPU: */
156 	.irq_dest_mode			= 0,
157 
158 	.disable_esr			= 1,
159 	.dest_logical			= 0,
160 	.check_apicid_used		= bigsmp_check_apicid_used,
161 
162 	.init_apic_ldr			= bigsmp_init_apic_ldr,
163 
164 	.ioapic_phys_id_map		= bigsmp_ioapic_phys_id_map,
165 	.setup_apic_routing		= bigsmp_setup_apic_routing,
166 	.cpu_present_to_apicid		= bigsmp_cpu_present_to_apicid,
167 	.apicid_to_cpu_present		= physid_set_mask_of_physid,
168 	.check_phys_apicid_present	= bigsmp_check_phys_apicid_present,
169 	.phys_pkg_id			= bigsmp_phys_pkg_id,
170 
171 	.get_apic_id			= bigsmp_get_apic_id,
172 	.set_apic_id			= NULL,
173 
174 	.calc_dest_apicid		= apic_default_calc_apicid,
175 
176 	.send_IPI			= default_send_IPI_single_phys,
177 	.send_IPI_mask			= default_send_IPI_mask_sequence_phys,
178 	.send_IPI_mask_allbutself	= NULL,
179 	.send_IPI_allbutself		= bigsmp_send_IPI_allbutself,
180 	.send_IPI_all			= bigsmp_send_IPI_all,
181 	.send_IPI_self			= default_send_IPI_self,
182 
183 	.inquire_remote_apic		= default_inquire_remote_apic,
184 
185 	.read				= native_apic_mem_read,
186 	.write				= native_apic_mem_write,
187 	.eoi_write			= native_apic_mem_write,
188 	.icr_read			= native_apic_icr_read,
189 	.icr_write			= native_apic_icr_write,
190 	.wait_icr_idle			= native_apic_wait_icr_idle,
191 	.safe_wait_icr_idle		= native_safe_apic_wait_icr_idle,
192 
193 	.x86_32_early_logical_apicid	= bigsmp_early_logical_apicid,
194 };
195 
196 void __init generic_bigsmp_probe(void)
197 {
198 	unsigned int cpu;
199 
200 	if (!probe_bigsmp())
201 		return;
202 
203 	apic = &apic_bigsmp;
204 
205 	for_each_possible_cpu(cpu) {
206 		if (early_per_cpu(x86_cpu_to_logical_apicid,
207 				  cpu) == BAD_APICID)
208 			continue;
209 		early_per_cpu(x86_cpu_to_logical_apicid, cpu) =
210 			bigsmp_early_logical_apicid(cpu);
211 	}
212 
213 	pr_info("Overriding APIC driver with %s\n", apic_bigsmp.name);
214 }
215 
216 apic_driver(apic_bigsmp);
217