summaryrefslogtreecommitdiff
path: root/arch/x86/kernel/jailhouse.c
blob: 4eb8f2d19a872f7bce16e680c7600ab9708b59c6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
// SPDX-License-Identifier: GPL-2.0
/*
 * Jailhouse paravirt_ops implementation
 *
 * Copyright (c) Siemens AG, 2015-2017
 *
 * Authors:
 *  Jan Kiszka <jan.kiszka@siemens.com>
 */

#include <linux/acpi_pmtmr.h>
#include <linux/kernel.h>
#include <linux/reboot.h>
#include <linux/serial_8250.h>
#include <asm/apic.h>
#include <asm/io_apic.h>
#include <asm/acpi.h>
#include <asm/cpu.h>
#include <asm/hypervisor.h>
#include <asm/i8259.h>
#include <asm/irqdomain.h>
#include <asm/pci_x86.h>
#include <asm/reboot.h>
#include <asm/setup.h>
#include <asm/jailhouse_para.h>

static struct jailhouse_setup_data setup_data;
#define SETUP_DATA_V1_LEN	(sizeof(setup_data.hdr) + sizeof(setup_data.v1))
#define SETUP_DATA_V2_LEN	(SETUP_DATA_V1_LEN + sizeof(setup_data.v2))

static unsigned int precalibrated_tsc_khz;

static void jailhouse_setup_irq(unsigned int irq)
{
	struct mpc_intsrc mp_irq = {
		.type		= MP_INTSRC,
		.irqtype	= mp_INT,
		.irqflag	= MP_IRQPOL_ACTIVE_HIGH | MP_IRQTRIG_EDGE,
		.srcbusirq	= irq,
		.dstirq		= irq,
	};
	mp_save_irq(&mp_irq);
}

static uint32_t jailhouse_cpuid_base(void)
{
	if (boot_cpu_data.cpuid_level < 0 ||
	    !boot_cpu_has(X86_FEATURE_HYPERVISOR))
		return 0;

	return hypervisor_cpuid_base("Jailhouse\0\0\0", 0);
}

static uint32_t __init jailhouse_detect(void)
{
	return jailhouse_cpuid_base();
}

static void jailhouse_get_wallclock(struct timespec64 *now)
{
	memset(now, 0, sizeof(*now));
}

static void __init jailhouse_timer_init(void)
{
	lapic_timer_period = setup_data.v1.apic_khz * (1000 / HZ);
}

static unsigned long jailhouse_get_tsc(void)
{
	return precalibrated_tsc_khz;
}

static void __init jailhouse_x2apic_init(void)
{
#ifdef CONFIG_X86_X2APIC
	if (!x2apic_enabled())
		return;
	/*
	 * We do not have access to IR inside Jailhouse non-root cells.  So
	 * we have to run in physical mode.
	 */
	x2apic_phys = 1;
	/*
	 * This will trigger the switch to apic_x2apic_phys.  Empty OEM IDs
	 * ensure that only this APIC driver picks up the call.
	 */
	default_acpi_madt_oem_check("", "");
#endif
}

static void __init jailhouse_get_smp_config(unsigned int early)
{
	struct ioapic_domain_cfg ioapic_cfg = {
		.type = IOAPIC_DOMAIN_STRICT,
		.ops = &mp_ioapic_irqdomain_ops,
	};
	unsigned int cpu;

	jailhouse_x2apic_init();

	register_lapic_address(0xfee00000);

	for (cpu = 0; cpu < setup_data.v1.num_cpus; cpu++) {
		generic_processor_info(setup_data.v1.cpu_ids[cpu],
				       boot_cpu_apic_version);
	}

	smp_found_config = 1;

	if (setup_data.v1.standard_ioapic) {
		mp_register_ioapic(0, 0xfec00000, gsi_top, &ioapic_cfg);

		if (IS_ENABLED(CONFIG_SERIAL_8250) &&
		    setup_data.hdr.version < 2) {
			/* Register 1:1 mapping for legacy UART IRQs 3 and 4 */
			jailhouse_setup_irq(3);
			jailhouse_setup_irq(4);
		}
	}
}

static void jailhouse_no_restart(void)
{
	pr_notice("Jailhouse: Restart not supported, halting\n");
	machine_halt();
}

static int __init jailhouse_pci_arch_init(void)
{
	pci_direct_init(1);

	/*
	 * There are no bridges on the virtual PCI root bus under Jailhouse,
	 * thus no other way to discover all devices than a full scan.
	 * Respect any overrides via the command line, though.
	 */
	if (pcibios_last_bus < 0)
		pcibios_last_bus = 0xff;

#ifdef CONFIG_PCI_MMCONFIG
	if (setup_data.v1.pci_mmconfig_base) {
		pci_mmconfig_add(0, 0, pcibios_last_bus,
				 setup_data.v1.pci_mmconfig_base);
		pci_mmcfg_arch_init();
	}
#endif

	return 0;
}

#ifdef CONFIG_SERIAL_8250
static inline bool jailhouse_uart_enabled(unsigned int uart_nr)
{
	return setup_data.v2.flags & BIT(uart_nr);
}

static void jailhouse_serial_fixup(int port, struct uart_port *up,
				   u32 *capabilities)
{
	static const u16 pcuart_base[] = {0x3f8, 0x2f8, 0x3e8, 0x2e8};
	unsigned int n;

	for (n = 0; n < ARRAY_SIZE(pcuart_base); n++) {
		if (pcuart_base[n] != up->iobase)
			continue;

		if (jailhouse_uart_enabled(n)) {
			pr_info("Enabling UART%u (port 0x%lx)\n", n,
				up->iobase);
			jailhouse_setup_irq(up->irq);
		} else {
			/* Deactivate UART if access isn't allowed */
			up->iobase = 0;
		}
		break;
	}
}

static void __init jailhouse_serial_workaround(void)
{
	/*
	 * There are flags inside setup_data that indicate availability of
	 * platform UARTs since setup data version 2.
	 *
	 * In case of version 1, we don't know which UARTs belong Linux. In
	 * this case, unconditionally register 1:1 mapping for legacy UART IRQs
	 * 3 and 4.
	 */
	if (setup_data.hdr.version > 1)
		serial8250_set_isa_configurator(jailhouse_serial_fixup);
}
#else /* !CONFIG_SERIAL_8250 */
static inline void jailhouse_serial_workaround(void)
{
}
#endif /* CONFIG_SERIAL_8250 */

static void __init jailhouse_init_platform(void)
{
	u64 pa_data = boot_params.hdr.setup_data;
	unsigned long setup_data_len;
	struct setup_data header;
	void *mapping;

	x86_init.irqs.pre_vector_init	= x86_init_noop;
	x86_init.timers.timer_init	= jailhouse_timer_init;
	x86_init.mpparse.get_smp_config	= jailhouse_get_smp_config;
	x86_init.pci.arch_init		= jailhouse_pci_arch_init;

	x86_platform.calibrate_cpu	= jailhouse_get_tsc;
	x86_platform.calibrate_tsc	= jailhouse_get_tsc;
	x86_platform.get_wallclock	= jailhouse_get_wallclock;
	x86_platform.legacy.rtc		= 0;
	x86_platform.legacy.warm_reset	= 0;
	x86_platform.legacy.i8042	= X86_LEGACY_I8042_PLATFORM_ABSENT;

	legacy_pic			= &null_legacy_pic;

	machine_ops.emergency_restart	= jailhouse_no_restart;

	while (pa_data) {
		mapping = early_memremap(pa_data, sizeof(header));
		memcpy(&header, mapping, sizeof(header));
		early_memunmap(mapping, sizeof(header));

		if (header.type == SETUP_JAILHOUSE)
			break;

		pa_data = header.next;
	}

	if (!pa_data)
		panic("Jailhouse: No valid setup data found");

	/* setup data must at least contain the header */
	if (header.len < sizeof(setup_data.hdr))
		goto unsupported;

	pa_data += offsetof(struct setup_data, data);
	setup_data_len = min_t(unsigned long, sizeof(setup_data),
			       (unsigned long)header.len);
	mapping = early_memremap(pa_data, setup_data_len);
	memcpy(&setup_data, mapping, setup_data_len);
	early_memunmap(mapping, setup_data_len);

	if (setup_data.hdr.version == 0 ||
	    setup_data.hdr.compatible_version !=
		JAILHOUSE_SETUP_REQUIRED_VERSION ||
	    (setup_data.hdr.version == 1 && header.len < SETUP_DATA_V1_LEN) ||
	    (setup_data.hdr.version >= 2 && header.len < SETUP_DATA_V2_LEN))
		goto unsupported;

	pmtmr_ioport = setup_data.v1.pm_timer_address;
	pr_debug("Jailhouse: PM-Timer IO Port: %#x\n", pmtmr_ioport);

	precalibrated_tsc_khz = setup_data.v1.tsc_khz;
	setup_force_cpu_cap(X86_FEATURE_TSC_KNOWN_FREQ);

	pci_probe = 0;

	/*
	 * Avoid that the kernel complains about missing ACPI tables - there
	 * are none in a non-root cell.
	 */
	disable_acpi();

	jailhouse_serial_workaround();
	return;

unsupported:
	panic("Jailhouse: Unsupported setup data structure");
}

bool jailhouse_paravirt(void)
{
	return jailhouse_cpuid_base() != 0;
}

static bool __init jailhouse_x2apic_available(void)
{
	/*
	 * The x2APIC is only available if the root cell enabled it. Jailhouse
	 * does not support switching between xAPIC and x2APIC.
	 */
	return x2apic_enabled();
}

const struct hypervisor_x86 x86_hyper_jailhouse __refconst = {
	.name			= "Jailhouse",
	.detect			= jailhouse_detect,
	.init.init_platform	= jailhouse_init_platform,
	.init.x2apic_available	= jailhouse_x2apic_available,
	.ignore_nopv		= true,
};