Merge branch irq/generic_handle_domain_irq-core into irq/irqchip-next

Simplify the handling of interrupts that require an IRQ domain
resolution:
- domains now cache the irqdata instead of the irq number
- consistent behaviour wrt RCU
- single lookup for architectures using sparse IRQs
- reduced boilerplate code in drivers.

* irq/generic_handle_domain_irq-core: (26 commits)
  irqchip: Bulk conversion to generic_handle_domain_irq()
  genirq: Move non-irqdomain handle_domain_irq() handling into ARM's handle_IRQ()
  genirq: Add generic_handle_domain_irq() helper
  irqchip/nvic: Convert from handle_IRQ() to handle_domain_irq()
  irqdesc: Fix __handle_domain_irq() comment
  genirq: Use irq_resolve_mapping() to implement __handle_domain_irq() and co
  irqdomain: Introduce irq_resolve_mapping()
  irqdomain: Protect the linear revmap with RCU
  irqdomain: Cache irq_data instead of a virq number in the revmap
  irqdomain: Use struct_size() helper when allocating irqdomain
  irqdomain: Make normal and nomap irqdomains exclusive
  powerpc: Move the use of irq_domain_add_nomap() behind a config option
  irqdomain: Reimplement irq_linear_revmap() with irq_find_mapping()
  irqdomain: Kill irq_domain_add_legacy_isa
  powerpc: Drop dependency between asm/irq.h and linux/irqdomain.h
  powerpc: Convert irq_domain_add_legacy_isa use to irq_domain_add_legacy
  scsi/ibmvscsi: Directly include linux/{of.h,irqdomain.h}
  powerpc: Add missing linux/{of.h,irqdomain.h} include directives
  MIPS: Do not include linux/irqdomain.h from asm/irq.h
  MIPS: Add missing linux/irqdomain.h includes
  ...

Author: Marc Zyngier

Documentation/core-api/irq/irq-domain.rst

@@ -146,7 +146,6 @@ Legacy
 
 	irq_domain_add_simple()
 	irq_domain_add_legacy()
-	irq_domain_add_legacy_isa()
 	irq_domain_create_simple()
 	irq_domain_create_legacy()
 

arch/arm/kernel/irq.c

@@ -63,7 +63,27 @@ int arch_show_interrupts(struct seq_file *p, int prec)
  */
 void handle_IRQ(unsigned int irq, struct pt_regs *regs)
 {
-	__handle_domain_irq(NULL, irq, false, regs);
+	struct pt_regs *old_regs = set_irq_regs(regs);
+	struct irq_desc *desc;
+
+	irq_enter();
+
+	/*
+	 * Some hardware gives randomly wrong interrupts.  Rather
+	 * than crashing, do something sensible.
+	 */
+	if (unlikely(!irq || irq >= nr_irqs))
+		desc = NULL;
+	else
+		desc = irq_to_desc(irq);
+
+	if (likely(desc))
+		handle_irq_desc(desc);
+	else
+		ack_bad_irq(irq);
+
+	irq_exit();
+	set_irq_regs(old_regs);
 }
 
 /*

arch/mips/include/asm/irq.h

@@ -11,7 +11,6 @@
 
 #include <linux/linkage.h>
 #include <linux/smp.h>
-#include <linux/irqdomain.h>
 
 #include <asm/mipsmtregs.h>
 

arch/mips/lantiq/xway/dma.c

@@ -12,6 +12,7 @@
 #include <linux/spinlock.h>
 #include <linux/clk.h>
 #include <linux/err.h>
+#include <linux/of.h>
 
 #include <lantiq_soc.h>
 #include <xway_dma.h>

arch/mips/pci/pci-rt3883.c

@@ -13,6 +13,7 @@
 #include <linux/init.h>
 #include <linux/delay.h>
 #include <linux/interrupt.h>
+#include <linux/irqdomain.h>
 #include <linux/of.h>
 #include <linux/of_irq.h>
 #include <linux/of_pci.h>

arch/mips/pci/pci-xtalk-bridge.c

@@ -13,6 +13,7 @@
 #include <linux/platform_data/xtalk-bridge.h>
 #include <linux/nvmem-consumer.h>
 #include <linux/crc16.h>
+#include <linux/irqdomain.h>
 
 #include <asm/pci/bridge.h>
 #include <asm/paccess.h>

arch/mips/sgi-ip27/ip27-irq.c

@@ -9,6 +9,7 @@
 
 #include <linux/interrupt.h>
 #include <linux/irq.h>
+#include <linux/irqdomain.h>
 #include <linux/ioport.h>
 #include <linux/kernel.h>
 #include <linux/bitops.h>

arch/mips/sgi-ip30/ip30-irq.c

@@ -6,6 +6,7 @@
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
+#include <linux/irqdomain.h>
 #include <linux/percpu.h>
 #include <linux/spinlock.h>
 #include <linux/tick.h>

arch/nios2/include/asm/irq.h

@@ -10,6 +10,5 @@
 #define NIOS2_CPU_NR_IRQS	32
 
 #include <asm-generic/irq.h>
-#include <linux/irqdomain.h>
 
 #endif

arch/nios2/kernel/irq.c

@@ -11,6 +11,7 @@
 
 #include <linux/init.h>
 #include <linux/interrupt.h>
+#include <linux/irqdomain.h>
 #include <linux/of.h>
 
 static u32 ienable;