1#include <linux/init.h>
2
3#include <asm/x86_init.h>
4#include <asm/apic.h>
5#include <asm/xen/hypercall.h>
6
7#include <xen/xen.h>
8#include <xen/interface/physdev.h>
9#include "xen-ops.h"
10#include "pmu.h"
11#include "smp.h"
12
13static unsigned int xen_io_apic_read(unsigned apic, unsigned reg)
14{
15	struct physdev_apic apic_op;
16	int ret;
17
18	apic_op.apic_physbase = mpc_ioapic_addr(apic);
19	apic_op.reg = reg;
20	ret = HYPERVISOR_physdev_op(PHYSDEVOP_apic_read, &apic_op);
21	if (!ret)
22		return apic_op.value;
23
24	/* fallback to return an emulated IO_APIC values */
25	if (reg == 0x1)
26		return 0x00170020;
27	else if (reg == 0x0)
28		return apic << 24;
29
30	return 0xfd;
31}
32
33static unsigned long xen_set_apic_id(unsigned int x)
34{
35	WARN_ON(1);
36	return x;
37}
38
39static unsigned int xen_get_apic_id(unsigned long x)
40{
41	return ((x)>>24) & 0xFFu;
42}
43
44static u32 xen_apic_read(u32 reg)
45{
46	struct xen_platform_op op = {
47		.cmd = XENPF_get_cpuinfo,
48		.interface_version = XENPF_INTERFACE_VERSION,
49		.u.pcpu_info.xen_cpuid = 0,
50	};
51	int ret = 0;
52
53	/* Shouldn't need this as APIC is turned off for PV, and we only
54	 * get called on the bootup processor. But just in case. */
55	if (!xen_initial_domain() || smp_processor_id())
56		return 0;
57
58	if (reg == APIC_LVR)
59		return 0x10;
60#ifdef CONFIG_X86_32
61	if (reg == APIC_LDR)
62		return SET_APIC_LOGICAL_ID(1UL << smp_processor_id());
63#endif
64	if (reg != APIC_ID)
65		return 0;
66
67	ret = HYPERVISOR_dom0_op(&op);
68	if (ret)
69		return 0;
70
71	return op.u.pcpu_info.apic_id << 24;
72}
73
74static void xen_apic_write(u32 reg, u32 val)
75{
76	if (reg == APIC_LVTPC) {
77		(void)pmu_apic_update(reg);
78		return;
79	}
80
81	/* Warn to see if there's any stray references */
82	WARN(1,"register: %x, value: %x\n", reg, val);
83}
84
85static u64 xen_apic_icr_read(void)
86{
87	return 0;
88}
89
90static void xen_apic_icr_write(u32 low, u32 id)
91{
92	/* Warn to see if there's any stray references */
93	WARN_ON(1);
94}
95
96static u32 xen_safe_apic_wait_icr_idle(void)
97{
98        return 0;
99}
100
101static int xen_apic_probe_pv(void)
102{
103	if (xen_pv_domain())
104		return 1;
105
106	return 0;
107}
108
109static int xen_madt_oem_check(char *oem_id, char *oem_table_id)
110{
111	return xen_pv_domain();
112}
113
114static int xen_id_always_valid(int apicid)
115{
116	return 1;
117}
118
119static int xen_id_always_registered(void)
120{
121	return 1;
122}
123
124static int xen_phys_pkg_id(int initial_apic_id, int index_msb)
125{
126	return initial_apic_id >> index_msb;
127}
128
129#ifdef CONFIG_X86_32
130static int xen_x86_32_early_logical_apicid(int cpu)
131{
132	/* Match with APIC_LDR read. Otherwise setup_local_APIC complains. */
133	return 1 << cpu;
134}
135#endif
136
137static void xen_noop(void)
138{
139}
140
141static void xen_silent_inquire(int apicid)
142{
143}
144
145static struct apic xen_pv_apic = {
146	.name 				= "Xen PV",
147	.probe 				= xen_apic_probe_pv,
148	.acpi_madt_oem_check		= xen_madt_oem_check,
149	.apic_id_valid 			= xen_id_always_valid,
150	.apic_id_registered 		= xen_id_always_registered,
151
152	/* .irq_delivery_mode - used in native_compose_msi_msg only */
153	/* .irq_dest_mode     - used in native_compose_msi_msg only */
154
155	.target_cpus			= default_target_cpus,
156	.disable_esr			= 0,
157	/* .dest_logical      -  default_send_IPI_ use it but we use our own. */
158	.check_apicid_used		= default_check_apicid_used, /* Used on 32-bit */
159
160	.vector_allocation_domain	= flat_vector_allocation_domain,
161	.init_apic_ldr			= xen_noop, /* setup_local_APIC calls it */
162
163	.ioapic_phys_id_map		= default_ioapic_phys_id_map, /* Used on 32-bit */
164	.setup_apic_routing		= NULL,
165	.cpu_present_to_apicid		= default_cpu_present_to_apicid,
166	.apicid_to_cpu_present		= physid_set_mask_of_physid, /* Used on 32-bit */
167	.check_phys_apicid_present	= default_check_phys_apicid_present, /* smp_sanity_check needs it */
168	.phys_pkg_id			= xen_phys_pkg_id, /* detect_ht */
169
170	.get_apic_id 			= xen_get_apic_id,
171	.set_apic_id 			= xen_set_apic_id, /* Can be NULL on 32-bit. */
172	.apic_id_mask			= 0xFF << 24, /* Used by verify_local_APIC. Match with what xen_get_apic_id does. */
173
174	.cpu_mask_to_apicid_and		= flat_cpu_mask_to_apicid_and,
175
176#ifdef CONFIG_SMP
177	.send_IPI_mask 			= xen_send_IPI_mask,
178	.send_IPI_mask_allbutself 	= xen_send_IPI_mask_allbutself,
179	.send_IPI_allbutself 		= xen_send_IPI_allbutself,
180	.send_IPI_all 			= xen_send_IPI_all,
181	.send_IPI_self 			= xen_send_IPI_self,
182#endif
183	/* .wait_for_init_deassert- used  by AP bootup - smp_callin which we don't use */
184	.inquire_remote_apic		= xen_silent_inquire,
185
186	.read				= xen_apic_read,
187	.write				= xen_apic_write,
188	.eoi_write			= xen_apic_write,
189
190	.icr_read 			= xen_apic_icr_read,
191	.icr_write 			= xen_apic_icr_write,
192	.wait_icr_idle 			= xen_noop,
193	.safe_wait_icr_idle 		= xen_safe_apic_wait_icr_idle,
194
195#ifdef CONFIG_X86_32
196	/* generic_processor_info and setup_local_APIC. */
197	.x86_32_early_logical_apicid	= xen_x86_32_early_logical_apicid,
198#endif
199};
200
201static void __init xen_apic_check(void)
202{
203	if (apic == &xen_pv_apic)
204		return;
205
206	pr_info("Switched APIC routing from %s to %s.\n", apic->name,
207		xen_pv_apic.name);
208	apic = &xen_pv_apic;
209}
210void __init xen_init_apic(void)
211{
212	x86_io_apic_ops.read = xen_io_apic_read;
213	/* On PV guests the APIC CPUID bit is disabled so none of the
214	 * routines end up executing. */
215	if (!xen_initial_domain())
216		apic = &xen_pv_apic;
217
218	x86_platform.apic_post_init = xen_apic_check;
219}
220apic_driver(xen_pv_apic);
221