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 <asm/apic.h>
 15#include <asm/cpu.h>
 16#include <asm/hypervisor.h>
 17#include <asm/i8259.h>
 18#include <asm/irqdomain.h>
 19#include <asm/pci_x86.h>
 20#include <asm/reboot.h>
 21#include <asm/setup.h>
 22
 23static __initdata struct jailhouse_setup_data setup_data;
 24static unsigned int precalibrated_tsc_khz;
 25
 26static uint32_t jailhouse_cpuid_base(void)
 27{
 28	if (boot_cpu_data.cpuid_level < 0 ||
 29	    !boot_cpu_has(X86_FEATURE_HYPERVISOR))
 30		return 0;
 31
 32	return hypervisor_cpuid_base("Jailhouse\0\0\0", 0);
 33}
 34
 35static uint32_t __init jailhouse_detect(void)
 36{
 37	return jailhouse_cpuid_base();
 38}
 39
 40static void jailhouse_get_wallclock(struct timespec *now)
 41{
 42	memset(now, 0, sizeof(*now));
 43}
 44
 45static void __init jailhouse_timer_init(void)
 46{
 47	lapic_timer_frequency = setup_data.apic_khz * (1000 / HZ);
 48}
 49
 50static unsigned long jailhouse_get_tsc(void)
 51{
 52	return precalibrated_tsc_khz;
 53}
 54
 55static void __init jailhouse_x2apic_init(void)
 56{
 57#ifdef CONFIG_X86_X2APIC
 58	if (!x2apic_enabled())
 59		return;
 60	/*
 61	 * We do not have access to IR inside Jailhouse non-root cells.  So
 62	 * we have to run in physical mode.
 63	 */
 64	x2apic_phys = 1;
 65	/*
 66	 * This will trigger the switch to apic_x2apic_phys.  Empty OEM IDs
 67	 * ensure that only this APIC driver picks up the call.
 68	 */
 69	default_acpi_madt_oem_check("", "");
 70#endif
 71}
 72
 73static void __init jailhouse_get_smp_config(unsigned int early)
 74{
 75	struct ioapic_domain_cfg ioapic_cfg = {
 76		.type = IOAPIC_DOMAIN_STRICT,
 77		.ops = &mp_ioapic_irqdomain_ops,
 78	};
 79	struct mpc_intsrc mp_irq = {
 80		.type = MP_INTSRC,
 81		.irqtype = mp_INT,
 82		.irqflag = MP_IRQPOL_ACTIVE_HIGH | MP_IRQTRIG_EDGE,
 83	};
 84	unsigned int cpu;
 85
 86	jailhouse_x2apic_init();
 87
 88	register_lapic_address(0xfee00000);
 89
 90	for (cpu = 0; cpu < setup_data.num_cpus; cpu++) {
 91		generic_processor_info(setup_data.cpu_ids[cpu],
 92				       boot_cpu_apic_version);
 93	}
 94
 95	smp_found_config = 1;
 96
 97	if (setup_data.standard_ioapic) {
 98		mp_register_ioapic(0, 0xfec00000, gsi_top, &ioapic_cfg);
 99
100		/* Register 1:1 mapping for legacy UART IRQs 3 and 4 */
101		mp_irq.srcbusirq = mp_irq.dstirq = 3;
102		mp_save_irq(&mp_irq);
103
104		mp_irq.srcbusirq = mp_irq.dstirq = 4;
105		mp_save_irq(&mp_irq);
106	}
107}
108
109static void jailhouse_no_restart(void)
110{
111	pr_notice("Jailhouse: Restart not supported, halting\n");
112	machine_halt();
113}
114
115static int __init jailhouse_pci_arch_init(void)
116{
117	pci_direct_init(1);
118
119	/*
120	 * There are no bridges on the virtual PCI root bus under Jailhouse,
121	 * thus no other way to discover all devices than a full scan.
122	 * Respect any overrides via the command line, though.
123	 */
124	if (pcibios_last_bus < 0)
125		pcibios_last_bus = 0xff;
126
127#ifdef CONFIG_PCI_MMCONFIG
128	if (setup_data.pci_mmconfig_base) {
129		pci_mmconfig_add(0, 0, pcibios_last_bus,
130				 setup_data.pci_mmconfig_base);
131		pci_mmcfg_arch_init();
132	}
133#endif
134
135	return 0;
136}
137
138static void __init jailhouse_init_platform(void)
139{
140	u64 pa_data = boot_params.hdr.setup_data;
141	struct setup_data header;
142	void *mapping;
143
144	x86_init.irqs.pre_vector_init	= x86_init_noop;
145	x86_init.timers.timer_init	= jailhouse_timer_init;
146	x86_init.mpparse.get_smp_config	= jailhouse_get_smp_config;
147	x86_init.pci.arch_init		= jailhouse_pci_arch_init;
148
149	x86_platform.calibrate_cpu	= jailhouse_get_tsc;
150	x86_platform.calibrate_tsc	= jailhouse_get_tsc;
151	x86_platform.get_wallclock	= jailhouse_get_wallclock;
152	x86_platform.legacy.rtc		= 0;
153	x86_platform.legacy.warm_reset	= 0;
154	x86_platform.legacy.i8042	= X86_LEGACY_I8042_PLATFORM_ABSENT;
155
156	legacy_pic			= &null_legacy_pic;
157
158	machine_ops.emergency_restart	= jailhouse_no_restart;
159
160	while (pa_data) {
161		mapping = early_memremap(pa_data, sizeof(header));
162		memcpy(&header, mapping, sizeof(header));
163		early_memunmap(mapping, sizeof(header));
164
165		if (header.type == SETUP_JAILHOUSE &&
166		    header.len >= sizeof(setup_data)) {
167			pa_data += offsetof(struct setup_data, data);
168
169			mapping = early_memremap(pa_data, sizeof(setup_data));
170			memcpy(&setup_data, mapping, sizeof(setup_data));
171			early_memunmap(mapping, sizeof(setup_data));
172
173			break;
174		}
175
176		pa_data = header.next;
177	}
178
179	if (!pa_data)
180		panic("Jailhouse: No valid setup data found");
181
182	if (setup_data.compatible_version > JAILHOUSE_SETUP_REQUIRED_VERSION)
183		panic("Jailhouse: Unsupported setup data structure");
184
185	pmtmr_ioport = setup_data.pm_timer_address;
186	pr_debug("Jailhouse: PM-Timer IO Port: %#x\n", pmtmr_ioport);
187
188	precalibrated_tsc_khz = setup_data.tsc_khz;
189	setup_force_cpu_cap(X86_FEATURE_TSC_KNOWN_FREQ);
190
191	pci_probe = 0;
192
193	/*
194	 * Avoid that the kernel complains about missing ACPI tables - there
195	 * are none in a non-root cell.
196	 */
197	disable_acpi();
198}
199
200bool jailhouse_paravirt(void)
201{
202	return jailhouse_cpuid_base() != 0;
203}
204
205static bool jailhouse_x2apic_available(void)
206{
207	/*
208	 * The x2APIC is only available if the root cell enabled it. Jailhouse
209	 * does not support switching between xAPIC and x2APIC.
210	 */
211	return x2apic_enabled();
212}
213
214const struct hypervisor_x86 x86_hyper_jailhouse __refconst = {
215	.name			= "Jailhouse",
216	.detect			= jailhouse_detect,
217	.init.init_platform	= jailhouse_init_platform,
218	.init.x2apic_available	= jailhouse_x2apic_available,
219};