1 files changed, 177 insertions, 0 deletions
diff --git a/arch/x86/kernel/apic/x2apic_phys.c b/arch/x86/kernel/apic/x2apic_phys.c
new file mode 100644
index 000000000..788cdb4ee
--- /dev/null
+++ b/arch/x86/kernel/apic/x2apic_phys.c
@@ -0,0 +1,177 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/cpumask.h>
+#include <linux/acpi.h>
+
+#include "local.h"
+
+int x2apic_phys;
+
+static struct apic apic_x2apic_phys;
+u32 x2apic_max_apicid __ro_after_init = UINT_MAX;
+
+void __init x2apic_set_max_apicid(u32 apicid)
+{
+	x2apic_max_apicid = apicid;
+	if (apic->x2apic_set_max_apicid)
+		apic->max_apic_id = apicid;
+}
+
+static int __init set_x2apic_phys_mode(char *arg)
+{
+	x2apic_phys = 1;
+	return 0;
+}
+early_param("x2apic_phys", set_x2apic_phys_mode);
+
+static bool x2apic_fadt_phys(void)
+{
+#ifdef CONFIG_ACPI
+	if ((acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID) &&
+		(acpi_gbl_FADT.flags & ACPI_FADT_APIC_PHYSICAL)) {
+		printk(KERN_DEBUG "System requires x2apic physical mode\n");
+		return true;
+	}
+#endif
+	return false;
+}
+
+static int x2apic_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
+{
+	return x2apic_enabled() && (x2apic_phys || x2apic_fadt_phys());
+}
+
+static void x2apic_send_IPI(int cpu, int vector)
+{
+	u32 dest = per_cpu(x86_cpu_to_apicid, cpu);
+
+	/* x2apic MSRs are special and need a special fence: */
+	weak_wrmsr_fence();
+	__x2apic_send_IPI_dest(dest, vector, APIC_DEST_PHYSICAL);
+}
+
+static void
+__x2apic_send_IPI_mask(const struct cpumask *mask, int vector, int apic_dest)
+{
+	unsigned long query_cpu;
+	unsigned long this_cpu;
+	unsigned long flags;
+
+	/* x2apic MSRs are special and need a special fence: */
+	weak_wrmsr_fence();
+
+	local_irq_save(flags);
+
+	this_cpu = smp_processor_id();
+	for_each_cpu(query_cpu, mask) {
+		if (apic_dest == APIC_DEST_ALLBUT && this_cpu == query_cpu)
+			continue;
+		__x2apic_send_IPI_dest(per_cpu(x86_cpu_to_apicid, query_cpu),
+				       vector, APIC_DEST_PHYSICAL);
+	}
+	local_irq_restore(flags);
+}
+
+static void x2apic_send_IPI_mask(const struct cpumask *mask, int vector)
+{
+	__x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLINC);
+}
+
+static void
+ x2apic_send_IPI_mask_allbutself(const struct cpumask *mask, int vector)
+{
+	__x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLBUT);
+}
+
+static void __x2apic_send_IPI_shorthand(int vector, u32 which)
+{
+	unsigned long cfg = __prepare_ICR(which, vector, 0);
+
+	/* x2apic MSRs are special and need a special fence: */
+	weak_wrmsr_fence();
+	native_x2apic_icr_write(cfg, 0);
+}
+
+void x2apic_send_IPI_allbutself(int vector)
+{
+	__x2apic_send_IPI_shorthand(vector, APIC_DEST_ALLBUT);
+}
+
+void x2apic_send_IPI_all(int vector)
+{
+	__x2apic_send_IPI_shorthand(vector, APIC_DEST_ALLINC);
+}
+
+void x2apic_send_IPI_self(int vector)
+{
+	apic_write(APIC_SELF_IPI, vector);
+}
+
+void __x2apic_send_IPI_dest(unsigned int apicid, int vector, unsigned int dest)
+{
+	unsigned long cfg = __prepare_ICR(0, vector, dest);
+	native_x2apic_icr_write(cfg, apicid);
+}
+
+static int x2apic_phys_probe(void)
+{
+	if (!x2apic_mode)
+		return 0;
+
+	if (x2apic_phys || x2apic_fadt_phys())
+		return 1;
+
+	return apic == &apic_x2apic_phys;
+}
+
+unsigned int x2apic_get_apic_id(unsigned long id)
+{
+	return id;
+}
+
+u32 x2apic_set_apic_id(unsigned int id)
+{
+	return id;
+}
+
+int x2apic_phys_pkg_id(int initial_apicid, int index_msb)
+{
+	return initial_apicid >> index_msb;
+}
+
+static struct apic apic_x2apic_phys __ro_after_init = {
+
+	.name				= "physical x2apic",
+	.probe				= x2apic_phys_probe,
+	.acpi_madt_oem_check		= x2apic_acpi_madt_oem_check,
+
+	.delivery_mode			= APIC_DELIVERY_MODE_FIXED,
+	.dest_mode_logical		= false,
+
+	.disable_esr			= 0,
+
+	.cpu_present_to_apicid		= default_cpu_present_to_apicid,
+	.phys_pkg_id			= x2apic_phys_pkg_id,
+
+	.max_apic_id			= UINT_MAX,
+	.x2apic_set_max_apicid		= true,
+	.get_apic_id			= x2apic_get_apic_id,
+	.set_apic_id			= x2apic_set_apic_id,
+
+	.calc_dest_apicid		= apic_default_calc_apicid,
+
+	.send_IPI			= x2apic_send_IPI,
+	.send_IPI_mask			= x2apic_send_IPI_mask,
+	.send_IPI_mask_allbutself	= x2apic_send_IPI_mask_allbutself,
+	.send_IPI_allbutself		= x2apic_send_IPI_allbutself,
+	.send_IPI_all			= x2apic_send_IPI_all,
+	.send_IPI_self			= x2apic_send_IPI_self,
+
+	.read				= native_apic_msr_read,
+	.write				= native_apic_msr_write,
+	.eoi				= native_apic_msr_eoi,
+	.icr_read			= native_x2apic_icr_read,
+	.icr_write			= native_x2apic_icr_write,
+};
+
+apic_driver(apic_x2apic_phys);