x86/PCI: Remove unused HyperTransport interrupt support

There are no in-tree callers of ht_create_irq(), the driver interface for
HyperTransport interrupts, left.  Remove the unused entry point and all the
supporting code.

See 8b955b0 ("[PATCH] Initial generic hypertransport interrupt
support").

Signed-off-by: Bjorn Helgaas <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Acked-by: "Eric W. Biederman" <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: [email protected]
Cc: Benjamin Herrenschmidt <[email protected]>
Link: https://lkml.kernel.org/r/20171122221337.3877.23362.stgit@bhelgaas-glaptop.roam.corp.google.com

Author: bjorn-helgaas

arch/x86/include/asm/hw_irq.h

@@ -99,14 +99,6 @@ struct irq_alloc_info {
 			void		*dmar_data;
 		};
 #endif
-#ifdef	CONFIG_HT_IRQ
-		struct {
-			int		ht_pos;
-			int		ht_idx;
-			struct pci_dev	*ht_dev;
-			void		*ht_update;
-		};
-#endif
 #ifdef	CONFIG_X86_UV
 		struct {
 			int		uv_limit;

arch/x86/include/asm/hypertransport.h

@@ -56,10 +56,4 @@ extern void arch_init_msi_domain(struct irq_domain *domain);
 static inline void arch_init_msi_domain(struct irq_domain *domain) { }
 #endif
 
-#ifdef CONFIG_HT_IRQ
-extern void arch_init_htirq_domain(struct irq_domain *domain);
-#else
-static inline void arch_init_htirq_domain(struct irq_domain *domain) { }
-#endif
-
 #endif

arch/x86/include/asm/irqdomain.h

@@ -12,7 +12,6 @@ obj-y				+= hw_nmi.o
 
 obj-$(CONFIG_X86_IO_APIC)	+= io_apic.o
 obj-$(CONFIG_PCI_MSI)		+= msi.o
-obj-$(CONFIG_HT_IRQ)		+= htirq.o
 obj-$(CONFIG_SMP)		+= ipi.o
 
 ifeq ($(CONFIG_X86_64),y)

arch/x86/kernel/apic/Makefile

@@ -1,5 +1,5 @@
 /*
- * Local APIC related interfaces to support IOAPIC, MSI, HT_IRQ etc.
+ * Local APIC related interfaces to support IOAPIC, MSI, etc.
  *
  * Copyright (C) 1997, 1998, 1999, 2000, 2009 Ingo Molnar, Hajnalka Szabo
  *	Moved from arch/x86/kernel/apic/io_apic.c.
@@ -601,7 +601,7 @@ int __init arch_probe_nr_irqs(void)
 		nr_irqs = NR_VECTORS * nr_cpu_ids;
 
 	nr = (gsi_top + nr_legacy_irqs()) + 8 * nr_cpu_ids;
-#if defined(CONFIG_PCI_MSI) || defined(CONFIG_HT_IRQ)
+#if defined(CONFIG_PCI_MSI)
 	/*
 	 * for MSI and HT dyn irq
 	 */
@@ -663,7 +663,6 @@ int __init arch_early_irq_init(void)
 	irq_set_default_host(x86_vector_domain);
 
 	arch_init_msi_domain(x86_vector_domain);
-	arch_init_htirq_domain(x86_vector_domain);
 
 	BUG_ON(!alloc_cpumask_var(&vector_searchmask, GFP_KERNEL));
 

arch/x86/kernel/apic/htirq.c

@@ -71,15 +71,6 @@ config XEN_PCIDEV_FRONTEND
           The PCI device frontend driver allows the kernel to import arbitrary
           PCI devices from a PCI backend to support PCI driver domains.
 
-config HT_IRQ
-	bool "Interrupts on hypertransport devices"
-	default y
-	depends on PCI && X86_LOCAL_APIC
-	help
-	   This allows native hypertransport devices to use interrupts.
-
-	   If unsure say Y.
-
 config PCI_ATS
 	bool
 

arch/x86/kernel/apic/vector.c

@@ -24,9 +24,6 @@ endif
 # Build the PCI MSI interrupt support
 obj-$(CONFIG_PCI_MSI) += msi.o
 
-# Build the Hypertransport interrupt support
-obj-$(CONFIG_HT_IRQ) += htirq.o
-
 obj-$(CONFIG_PCI_ATS) += ats.o
 obj-$(CONFIG_PCI_IOV) += iov.o