1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Jailhouse paravirt_ops implementation
4 *
5 * Copyright (c) Siemens AG, 2015-2017
6 *
7 * Authors:
8 * Jan Kiszka <jan.kiszka@siemens.com>
9 */
10
11#include <linux/acpi_pmtmr.h>
12#include <linux/kernel.h>
13#include <linux/reboot.h>
14#include <linux/serial_8250.h>
15#include <asm/apic.h>
16#include <asm/io_apic.h>
17#include <asm/acpi.h>
18#include <asm/cpu.h>
19#include <asm/hypervisor.h>
20#include <asm/i8259.h>
21#include <asm/irqdomain.h>
22#include <asm/pci_x86.h>
23#include <asm/reboot.h>
24#include <asm/setup.h>
25#include <asm/jailhouse_para.h>
26
27static struct jailhouse_setup_data setup_data;
28#define SETUP_DATA_V1_LEN (sizeof(setup_data.hdr) + sizeof(setup_data.v1))
29#define SETUP_DATA_V2_LEN (SETUP_DATA_V1_LEN + sizeof(setup_data.v2))
30
31static unsigned int precalibrated_tsc_khz;
32
33static void jailhouse_setup_irq(unsigned int irq)
34{
35 struct mpc_intsrc mp_irq = {
36 .type = MP_INTSRC,
37 .irqtype = mp_INT,
38 .irqflag = MP_IRQPOL_ACTIVE_HIGH | MP_IRQTRIG_EDGE,
39 .srcbusirq = irq,
40 .dstirq = irq,
41 };
42 mp_save_irq(m: &mp_irq);
43}
44
45static uint32_t jailhouse_cpuid_base(void)
46{
47 if (boot_cpu_data.cpuid_level < 0 ||
48 !boot_cpu_has(X86_FEATURE_HYPERVISOR))
49 return 0;
50
51 return hypervisor_cpuid_base(sig: "Jailhouse\0\0\0", leaves: 0);
52}
53
54static uint32_t __init jailhouse_detect(void)
55{
56 return jailhouse_cpuid_base();
57}
58
59static void jailhouse_get_wallclock(struct timespec64 *now)
60{
61 memset(now, 0, sizeof(*now));
62}
63
64static void __init jailhouse_timer_init(void)
65{
66 lapic_timer_period = setup_data.v1.apic_khz * (1000 / HZ);
67}
68
69static unsigned long jailhouse_get_tsc(void)
70{
71 return precalibrated_tsc_khz;
72}
73
74static void __init jailhouse_x2apic_init(void)
75{
76#ifdef CONFIG_X86_X2APIC
77 if (!x2apic_enabled())
78 return;
79 /*
80 * We do not have access to IR inside Jailhouse non-root cells. So
81 * we have to run in physical mode.
82 */
83 x2apic_phys = 1;
84 /*
85 * This will trigger the switch to apic_x2apic_phys. Empty OEM IDs
86 * ensure that only this APIC driver picks up the call.
87 */
88 default_acpi_madt_oem_check("", "");
89#endif
90}
91
92static void __init jailhouse_get_smp_config(unsigned int early)
93{
94 struct ioapic_domain_cfg ioapic_cfg = {
95 .type = IOAPIC_DOMAIN_STRICT,
96 .ops = &mp_ioapic_irqdomain_ops,
97 };
98 unsigned int cpu;
99
100 jailhouse_x2apic_init();
101
102 register_lapic_address(address: 0xfee00000);
103
104 for (cpu = 0; cpu < setup_data.v1.num_cpus; cpu++)
105 generic_processor_info(apicid: setup_data.v1.cpu_ids[cpu]);
106
107 smp_found_config = 1;
108
109 if (setup_data.v1.standard_ioapic) {
110 mp_register_ioapic(id: 0, address: 0xfec00000, gsi_base: gsi_top, cfg: &ioapic_cfg);
111
112 if (IS_ENABLED(CONFIG_SERIAL_8250) &&
113 setup_data.hdr.version < 2) {
114 /* Register 1:1 mapping for legacy UART IRQs 3 and 4 */
115 jailhouse_setup_irq(irq: 3);
116 jailhouse_setup_irq(irq: 4);
117 }
118 }
119}
120
121static void jailhouse_no_restart(void)
122{
123 pr_notice("Jailhouse: Restart not supported, halting\n");
124 machine_halt();
125}
126
127static int __init jailhouse_pci_arch_init(void)
128{
129 pci_direct_init(type: 1);
130
131 /*
132 * There are no bridges on the virtual PCI root bus under Jailhouse,
133 * thus no other way to discover all devices than a full scan.
134 * Respect any overrides via the command line, though.
135 */
136 if (pcibios_last_bus < 0)
137 pcibios_last_bus = 0xff;
138
139#ifdef CONFIG_PCI_MMCONFIG
140 if (setup_data.v1.pci_mmconfig_base) {
141 pci_mmconfig_add(segment: 0, start: 0, end: pcibios_last_bus,
142 addr: setup_data.v1.pci_mmconfig_base);
143 pci_mmcfg_arch_init();
144 }
145#endif
146
147 return 0;
148}
149
150#ifdef CONFIG_SERIAL_8250
151static inline bool jailhouse_uart_enabled(unsigned int uart_nr)
152{
153 return setup_data.v2.flags & BIT(uart_nr);
154}
155
156static void jailhouse_serial_fixup(int port, struct uart_port *up,
157 u32 *capabilities)
158{
159 static const u16 pcuart_base[] = {0x3f8, 0x2f8, 0x3e8, 0x2e8};
160 unsigned int n;
161
162 for (n = 0; n < ARRAY_SIZE(pcuart_base); n++) {
163 if (pcuart_base[n] != up->iobase)
164 continue;
165
166 if (jailhouse_uart_enabled(uart_nr: n)) {
167 pr_info("Enabling UART%u (port 0x%lx)\n", n,
168 up->iobase);
169 jailhouse_setup_irq(irq: up->irq);
170 } else {
171 /* Deactivate UART if access isn't allowed */
172 up->iobase = 0;
173 }
174 break;
175 }
176}
177
178static void __init jailhouse_serial_workaround(void)
179{
180 /*
181 * There are flags inside setup_data that indicate availability of
182 * platform UARTs since setup data version 2.
183 *
184 * In case of version 1, we don't know which UARTs belong Linux. In
185 * this case, unconditionally register 1:1 mapping for legacy UART IRQs
186 * 3 and 4.
187 */
188 if (setup_data.hdr.version > 1)
189 serial8250_set_isa_configurator(v: jailhouse_serial_fixup);
190}
191#else /* !CONFIG_SERIAL_8250 */
192static inline void jailhouse_serial_workaround(void)
193{
194}
195#endif /* CONFIG_SERIAL_8250 */
196
197static void __init jailhouse_init_platform(void)
198{
199 u64 pa_data = boot_params.hdr.setup_data;
200 unsigned long setup_data_len;
201 struct setup_data header;
202 void *mapping;
203
204 x86_init.irqs.pre_vector_init = x86_init_noop;
205 x86_init.timers.timer_init = jailhouse_timer_init;
206 x86_init.mpparse.get_smp_config = jailhouse_get_smp_config;
207 x86_init.pci.arch_init = jailhouse_pci_arch_init;
208
209 x86_platform.calibrate_cpu = jailhouse_get_tsc;
210 x86_platform.calibrate_tsc = jailhouse_get_tsc;
211 x86_platform.get_wallclock = jailhouse_get_wallclock;
212 x86_platform.legacy.rtc = 0;
213 x86_platform.legacy.warm_reset = 0;
214 x86_platform.legacy.i8042 = X86_LEGACY_I8042_PLATFORM_ABSENT;
215
216 legacy_pic = &null_legacy_pic;
217
218 machine_ops.emergency_restart = jailhouse_no_restart;
219
220 while (pa_data) {
221 mapping = early_memremap(phys_addr: pa_data, size: sizeof(header));
222 memcpy(&header, mapping, sizeof(header));
223 early_memunmap(addr: mapping, size: sizeof(header));
224
225 if (header.type == SETUP_JAILHOUSE)
226 break;
227
228 pa_data = header.next;
229 }
230
231 if (!pa_data)
232 panic(fmt: "Jailhouse: No valid setup data found");
233
234 /* setup data must at least contain the header */
235 if (header.len < sizeof(setup_data.hdr))
236 goto unsupported;
237
238 pa_data += offsetof(struct setup_data, data);
239 setup_data_len = min_t(unsigned long, sizeof(setup_data),
240 (unsigned long)header.len);
241 mapping = early_memremap(phys_addr: pa_data, size: setup_data_len);
242 memcpy(&setup_data, mapping, setup_data_len);
243 early_memunmap(addr: mapping, size: setup_data_len);
244
245 if (setup_data.hdr.version == 0 ||
246 setup_data.hdr.compatible_version !=
247 JAILHOUSE_SETUP_REQUIRED_VERSION ||
248 (setup_data.hdr.version == 1 && header.len < SETUP_DATA_V1_LEN) ||
249 (setup_data.hdr.version >= 2 && header.len < SETUP_DATA_V2_LEN))
250 goto unsupported;
251
252 pmtmr_ioport = setup_data.v1.pm_timer_address;
253 pr_debug("Jailhouse: PM-Timer IO Port: %#x\n", pmtmr_ioport);
254
255 precalibrated_tsc_khz = setup_data.v1.tsc_khz;
256 setup_force_cpu_cap(X86_FEATURE_TSC_KNOWN_FREQ);
257
258 pci_probe = 0;
259
260 /*
261 * Avoid that the kernel complains about missing ACPI tables - there
262 * are none in a non-root cell.
263 */
264 disable_acpi();
265
266 jailhouse_serial_workaround();
267 return;
268
269unsupported:
270 panic(fmt: "Jailhouse: Unsupported setup data structure");
271}
272
273bool jailhouse_paravirt(void)
274{
275 return jailhouse_cpuid_base() != 0;
276}
277
278static bool __init jailhouse_x2apic_available(void)
279{
280 /*
281 * The x2APIC is only available if the root cell enabled it. Jailhouse
282 * does not support switching between xAPIC and x2APIC.
283 */
284 return x2apic_enabled();
285}
286
287const struct hypervisor_x86 x86_hyper_jailhouse __refconst = {
288 .name = "Jailhouse",
289 .detect = jailhouse_detect,
290 .init.init_platform = jailhouse_init_platform,
291 .init.x2apic_available = jailhouse_x2apic_available,
292 .ignore_nopv = true,
293};
294

source code of linux/arch/x86/kernel/jailhouse.c