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