1 files changed, 295 insertions, 0 deletions
diff --git a/arch/x86/kernel/jailhouse.c b/arch/x86/kernel/jailhouse.c
new file mode 100644
index 000000000..4eb8f2d19
--- /dev/null
+++ b/arch/x86/kernel/jailhouse.c
@@ -0,0 +1,295 @@
+// 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,
+};