1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/init.h>
3 #include <linux/thread_info.h>
4
5 #include <asm/x86_init.h>
6 #include <asm/apic.h>
7 #include <asm/io_apic.h>
8 #include <asm/xen/hypercall.h>
9
10 #include <xen/xen.h>
11 #include <xen/interface/physdev.h>
12 #include "xen-ops.h"
13 #include "pmu.h"
14 #include "smp.h"
15
xen_io_apic_read(unsigned apic,unsigned reg)16 static unsigned int xen_io_apic_read(unsigned apic, unsigned reg)
17 {
18 struct physdev_apic apic_op;
19 int ret;
20
21 apic_op.apic_physbase = mpc_ioapic_addr(apic);
22 apic_op.reg = reg;
23 ret = HYPERVISOR_physdev_op(PHYSDEVOP_apic_read, &apic_op);
24 if (!ret)
25 return apic_op.value;
26
27 /* fallback to return an emulated IO_APIC values */
28 if (reg == 0x1)
29 return 0x00170020;
30 else if (reg == 0x0)
31 return apic << 24;
32
33 return 0xfd;
34 }
35
xen_set_apic_id(unsigned int x)36 static u32 xen_set_apic_id(unsigned int x)
37 {
38 WARN_ON(1);
39 return x;
40 }
41
xen_get_apic_id(unsigned long x)42 static unsigned int xen_get_apic_id(unsigned long x)
43 {
44 return ((x)>>24) & 0xFFu;
45 }
46
xen_apic_read(u32 reg)47 static u32 xen_apic_read(u32 reg)
48 {
49 struct xen_platform_op op = {
50 .cmd = XENPF_get_cpuinfo,
51 .interface_version = XENPF_INTERFACE_VERSION,
52 .u.pcpu_info.xen_cpuid = 0,
53 };
54 int ret = 0;
55
56 /* Shouldn't need this as APIC is turned off for PV, and we only
57 * get called on the bootup processor. But just in case. */
58 if (!xen_initial_domain() || smp_processor_id())
59 return 0;
60
61 if (reg == APIC_LVR)
62 return 0x14;
63 if (reg != APIC_ID)
64 return 0;
65
66 ret = HYPERVISOR_platform_op(&op);
67 if (ret)
68 op.u.pcpu_info.apic_id = BAD_APICID;
69
70 return op.u.pcpu_info.apic_id << 24;
71 }
72
xen_apic_write(u32 reg,u32 val)73 static void xen_apic_write(u32 reg, u32 val)
74 {
75 if (reg == APIC_LVTPC) {
76 (void)pmu_apic_update(reg);
77 return;
78 }
79
80 /* Warn to see if there's any stray references */
81 WARN(1,"register: %x, value: %x\n", reg, val);
82 }
83
xen_apic_icr_read(void)84 static u64 xen_apic_icr_read(void)
85 {
86 return 0;
87 }
88
xen_apic_icr_write(u32 low,u32 id)89 static void xen_apic_icr_write(u32 low, u32 id)
90 {
91 /* Warn to see if there's any stray references */
92 WARN_ON(1);
93 }
94
xen_safe_apic_wait_icr_idle(void)95 static u32 xen_safe_apic_wait_icr_idle(void)
96 {
97 return 0;
98 }
99
xen_apic_probe_pv(void)100 static int xen_apic_probe_pv(void)
101 {
102 if (xen_pv_domain())
103 return 1;
104
105 return 0;
106 }
107
xen_madt_oem_check(char * oem_id,char * oem_table_id)108 static int xen_madt_oem_check(char *oem_id, char *oem_table_id)
109 {
110 return xen_pv_domain();
111 }
112
xen_id_always_valid(u32 apicid)113 static int xen_id_always_valid(u32 apicid)
114 {
115 return 1;
116 }
117
xen_id_always_registered(void)118 static int xen_id_always_registered(void)
119 {
120 return 1;
121 }
122
xen_phys_pkg_id(int initial_apic_id,int index_msb)123 static int xen_phys_pkg_id(int initial_apic_id, int index_msb)
124 {
125 return initial_apic_id >> index_msb;
126 }
127
xen_noop(void)128 static void xen_noop(void)
129 {
130 }
131
xen_silent_inquire(int apicid)132 static void xen_silent_inquire(int apicid)
133 {
134 }
135
xen_cpu_present_to_apicid(int cpu)136 static int xen_cpu_present_to_apicid(int cpu)
137 {
138 if (cpu_present(cpu))
139 return cpu_data(cpu).apicid;
140 else
141 return BAD_APICID;
142 }
143
144 static struct apic xen_pv_apic = {
145 .name = "Xen PV",
146 .probe = xen_apic_probe_pv,
147 .acpi_madt_oem_check = xen_madt_oem_check,
148 .apic_id_valid = xen_id_always_valid,
149 .apic_id_registered = xen_id_always_registered,
150
151 /* .delivery_mode and .dest_mode_logical not used by XENPV */
152
153 .disable_esr = 0,
154
155 .check_apicid_used = default_check_apicid_used, /* Used on 32-bit */
156 .init_apic_ldr = xen_noop, /* setup_local_APIC calls it */
157 .ioapic_phys_id_map = default_ioapic_phys_id_map, /* Used on 32-bit */
158 .setup_apic_routing = NULL,
159 .cpu_present_to_apicid = xen_cpu_present_to_apicid,
160 .apicid_to_cpu_present = physid_set_mask_of_physid, /* Used on 32-bit */
161 .check_phys_apicid_present = default_check_phys_apicid_present, /* smp_sanity_check needs it */
162 .phys_pkg_id = xen_phys_pkg_id, /* detect_ht */
163
164 .get_apic_id = xen_get_apic_id,
165 .set_apic_id = xen_set_apic_id, /* Can be NULL on 32-bit. */
166
167 .calc_dest_apicid = apic_flat_calc_apicid,
168
169 #ifdef CONFIG_SMP
170 .send_IPI_mask = xen_send_IPI_mask,
171 .send_IPI_mask_allbutself = xen_send_IPI_mask_allbutself,
172 .send_IPI_allbutself = xen_send_IPI_allbutself,
173 .send_IPI_all = xen_send_IPI_all,
174 .send_IPI_self = xen_send_IPI_self,
175 #endif
176 /* .wait_for_init_deassert- used by AP bootup - smp_callin which we don't use */
177 .inquire_remote_apic = xen_silent_inquire,
178
179 .read = xen_apic_read,
180 .write = xen_apic_write,
181 .eoi_write = xen_apic_write,
182
183 .icr_read = xen_apic_icr_read,
184 .icr_write = xen_apic_icr_write,
185 .wait_icr_idle = xen_noop,
186 .safe_wait_icr_idle = xen_safe_apic_wait_icr_idle,
187 };
188
xen_apic_check(void)189 static void __init xen_apic_check(void)
190 {
191 if (apic == &xen_pv_apic)
192 return;
193
194 pr_info("Switched APIC routing from %s to %s.\n", apic->name,
195 xen_pv_apic.name);
196 apic = &xen_pv_apic;
197 }
xen_init_apic(void)198 void __init xen_init_apic(void)
199 {
200 x86_apic_ops.io_apic_read = xen_io_apic_read;
201 /* On PV guests the APIC CPUID bit is disabled so none of the
202 * routines end up executing. */
203 if (!xen_initial_domain())
204 apic = &xen_pv_apic;
205
206 x86_platform.apic_post_init = xen_apic_check;
207 }
208 apic_driver(xen_pv_apic);
209