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(&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("Jailhouse\0\0\0", 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(0xfee00000);
103
104	for (cpu = 0; cpu < setup_data.v1.num_cpus; cpu++)
105		generic_processor_info(setup_data.v1.cpu_ids[cpu]);
106
107	smp_found_config = 1;
108
109	if (setup_data.v1.standard_ioapic) {
110		mp_register_ioapic(0, 0xfec00000, gsi_top, &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(3);
116			jailhouse_setup_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(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(0, 0, pcibios_last_bus,
142				 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(n)) {
167			pr_info("Enabling UART%u (port 0x%lx)\n", n,
168				up->iobase);
169			jailhouse_setup_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(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(pa_data, sizeof(header));
222		memcpy(&header, mapping, sizeof(header));
223		early_memunmap(mapping, 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("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(pa_data, setup_data_len);
242	memcpy(&setup_data, mapping, setup_data_len);
243	early_memunmap(mapping, 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("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};