[PATCH 13/21] convert generic irq code to irq controller

[zippel@linux-m68k.org]

[-- Attachment #1: 0019-M68K-convert-generic-irq-code-to-irq-controller.txt --]
[-- Type: text/plain, Size: 18493 bytes --]

Convert the generic irq code to use irq controller, this gets rid of the
machine specific callbacks and gives better control over irq handling
without duplicating lots of code.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>

---

 arch/m68k/kernel/entry.S      |   11 +-
 arch/m68k/kernel/ints.c       |  240 ++++++++++++++++++++++++++---------------
 arch/m68k/kernel/m68k_ksyms.c |    2 
 arch/m68k/kernel/setup.c      |    3 -
 arch/m68k/kernel/traps.c      |    7 +
 include/asm-m68k/irq.h        |   65 ++++-------
 include/asm-m68k/machdep.h    |    6 -
 include/asm-m68k/traps.h      |    2 
 8 files changed, 188 insertions(+), 148 deletions(-)

58f615bf9135a7bc00999b29deffd0c5f9cc971b
diff --git a/arch/m68k/kernel/entry.S b/arch/m68k/kernel/entry.S
index 1fb88f3..48cccc5 100644
--- a/arch/m68k/kernel/entry.S
+++ b/arch/m68k/kernel/entry.S
@@ -48,6 +48,8 @@ #include <asm/asm-offsets.h>
 .globl sys_call_table
 .globl sys_fork, sys_clone, sys_vfork
 .globl ret_from_interrupt, bad_interrupt
+.globl auto_irqhandler_fixup
+.globl user_irqvec_fixup, user_irqhandler_fixup
 
 .text
 ENTRY(buserr)
@@ -212,6 +214,7 @@ #if defined(MACH_Q40_ONLY) && defined(CO
 	jbra	3f
 1:
 #endif
+auto_irqhandler_fixup = . + 2
 	jsr	m68k_handle_int		|  process the IRQ
 3:	addql	#8,%sp			|  pop parameters off stack
 
@@ -234,17 +237,19 @@ ret_from_last_interrupt:
 
 /* Handler for user defined interrupt vectors */
 
-ENTRY(mach_inthandler)
+ENTRY(user_inthandler)
 	SAVE_ALL_INT
 	GET_CURRENT(%d0)
 	addqb	#1,%curptr@(TASK_INFO+TINFO_PREEMPT+1)
 					|  put exception # in d0
 	bfextu	%sp@(PT_VECTOR){#4,#10},%d0
+user_irqvec_fixup = . + 2
+	subw	#VEC_USER,%d0
 
 	movel	%sp,%sp@-
 	movel	%d0,%sp@-		|  put vector # on stack
-	movel	mach_process_int,%a0
-	jsr	%a0@			|  process the IRQ
+user_irqhandler_fixup = . + 2
+	jsr	m68k_handle_int		|  process the IRQ
 	addql	#8,%sp			|  pop parameters off stack
 
 	subqb	#1,%curptr@(TASK_INFO+TINFO_PREEMPT+1)
diff --git a/arch/m68k/kernel/ints.c b/arch/m68k/kernel/ints.c
index c7f6ee6..5a8344b 100644
--- a/arch/m68k/kernel/ints.c
+++ b/arch/m68k/kernel/ints.c
@@ -39,14 +39,22 @@ #include <asm/irq.h>
 #include <asm/traps.h>
 #include <asm/page.h>
 #include <asm/machdep.h>
+#include <asm/cacheflush.h>
 
 #ifdef CONFIG_Q40
 #include <asm/q40ints.h>
 #endif
 
+extern u32 auto_irqhandler_fixup[];
+extern u32 user_irqhandler_fixup[];
+extern u16 user_irqvec_fixup[];
+
 /* table for system interrupt handlers */
-static struct irq_node *irq_list[SYS_IRQS];
-static struct irq_controller *irq_controller[SYS_IRQS];
+static struct irq_node *irq_list[NR_IRQS];
+static struct irq_controller *irq_controller[NR_IRQS];
+static int irq_depth[NR_IRQS];
+
+static int m68k_first_user_vec;
 
 static struct irq_controller auto_irq_controller = {
 	.name		= "auto",
@@ -55,39 +63,16 @@ static struct irq_controller auto_irq_co
 	.shutdown	= m68k_irq_shutdown,
 };
 
-static const char *default_names[SYS_IRQS] = {
-	[0] = "spurious int",
-	[1] = "int1 handler",
-	[2] = "int2 handler",
-	[3] = "int3 handler",
-	[4] = "int4 handler",
-	[5] = "int5 handler",
-	[6] = "int6 handler",
-	[7] = "int7 handler"
+static struct irq_controller user_irq_controller = {
+	.name		= "user",
+	.lock		= SPIN_LOCK_UNLOCKED,
+	.startup	= m68k_irq_startup,
+	.shutdown	= m68k_irq_shutdown,
 };
 
-/* The number of spurious interrupts */
-volatile unsigned int num_spurious;
-
 #define NUM_IRQ_NODES 100
 static irq_node_t nodes[NUM_IRQ_NODES];
 
-static void dummy_enable_irq(unsigned int irq);
-static void dummy_disable_irq(unsigned int irq);
-static int dummy_request_irq(unsigned int irq,
-		irqreturn_t (*handler) (int, void *, struct pt_regs *),
-		unsigned long flags, const char *devname, void *dev_id);
-static void dummy_free_irq(unsigned int irq, void *dev_id);
-
-void (*enable_irq) (unsigned int) = dummy_enable_irq;
-void (*disable_irq) (unsigned int) = dummy_disable_irq;
-
-int (*mach_request_irq) (unsigned int, irqreturn_t (*)(int, void *, struct pt_regs *),
-                      unsigned long, const char *, void *) = dummy_request_irq;
-void (*mach_free_irq) (unsigned int, void *) = dummy_free_irq;
-
-void init_irq_proc(void);
-
 /*
  * void init_IRQ(void)
  *
@@ -109,14 +94,70 @@ void __init init_IRQ(void)
 		hardirq_mask_is_broken();
 	}
 
-	for (i = IRQ_AUTO_1; i <= IRQ_AUTO_7; i++) {
+	for (i = IRQ_AUTO_1; i <= IRQ_AUTO_7; i++)
 		irq_controller[i] = &auto_irq_controller;
-		if (mach_default_handler && (*mach_default_handler)[i])
-			cpu_request_irq(i, (*mach_default_handler)[i],
-					0, default_names[i], NULL);
-	}
 
-	mach_init_IRQ ();
+	mach_init_IRQ();
+}
+
+/**
+ * m68k_setup_auto_interrupt
+ * @handler: called from auto vector interrupts
+ *
+ * setup the handler to be called from auto vector interrupts instead of the
+ * standard m68k_handle_int(), it will be called with irq numbers in the range
+ * from IRQ_AUTO_1 - IRQ_AUTO_7.
+ */
+void __init m68k_setup_auto_interrupt(void (*handler)(unsigned int, struct pt_regs *))
+{
+	if (handler)
+		*auto_irqhandler_fixup = (u32)handler;
+	flush_icache();
+}
+
+/**
+ * m68k_setup_user_interrupt
+ * @vec: first user vector interrupt to handle
+ * @cnt: number of active user vector interrupts
+ * @handler: called from user vector interrupts
+ *
+ * setup user vector interrupts, this includes activating the specified range
+ * of interrupts, only then these interrupts can be requested (note: this is
+ * different from auto vector interrupts). An optional handler can be installed
+ * to be called instead of the default m68k_handle_int(), it will be called
+ * with irq numbers starting from IRQ_USER.
+ */
+void __init m68k_setup_user_interrupt(unsigned int vec, unsigned int cnt,
+				      void (*handler)(unsigned int, struct pt_regs *))
+{
+	int i;
+
+	m68k_first_user_vec = vec;
+	for (i = 0; i < cnt; i++)
+		irq_controller[IRQ_USER + i] = &user_irq_controller;
+	*user_irqvec_fixup = vec - IRQ_USER;
+	if (handler)
+		*user_irqhandler_fixup = (u32)handler;
+	flush_icache();
+}
+
+/**
+ * m68k_setup_irq_controller
+ * @contr: irq controller which controls specified irq
+ * @irq: first irq to be managed by the controller
+ *
+ * Change the controller for the specified range of irq, which will be used to
+ * manage these irq. auto/user irq already have a default controller, which can
+ * be changed as well, but the controller probably should use m68k_irq_startup/
+ * m68k_irq_shutdown.
+ */
+void m68k_setup_irq_controller(struct irq_controller *contr, unsigned int irq,
+			       unsigned int cnt)
+{
+	int i;
+
+	for (i = 0; i < cnt; i++)
+		irq_controller[irq + i] = contr;
 }
 
 irq_node_t *new_irq_node(void)
@@ -135,34 +176,13 @@ irq_node_t *new_irq_node(void)
 	return NULL;
 }
 
-/*
- * We will keep these functions until I have convinced Linus to move
- * the declaration of them from include/linux/sched.h to
- * include/asm/irq.h.
- */
-int request_irq(unsigned int irq,
-		irqreturn_t (*handler) (int, void *, struct pt_regs *),
-		unsigned long flags, const char *devname, void *dev_id)
-{
-	return mach_request_irq(irq, handler, flags, devname, dev_id);
-}
-
-EXPORT_SYMBOL(request_irq);
-
-void free_irq(unsigned int irq, void *dev_id)
-{
-	mach_free_irq(irq, dev_id);
-}
-
-EXPORT_SYMBOL(free_irq);
-
 int setup_irq(unsigned int irq, struct irq_node *node)
 {
 	struct irq_controller *contr;
 	struct irq_node **prev;
 	unsigned long flags;
 
-	if (irq >= SYS_IRQS || !(contr = irq_controller[irq])) {
+	if (irq >= NR_IRQS || !(contr = irq_controller[irq])) {
 		printk("%s: Incorrect IRQ %d from %s\n",
 		       __FUNCTION__, irq, node->devname);
 		return -ENXIO;
@@ -195,9 +215,9 @@ int setup_irq(unsigned int irq, struct i
 	return 0;
 }
 
-int cpu_request_irq(unsigned int irq,
-                    irqreturn_t (*handler)(int, void *, struct pt_regs *),
-                    unsigned long flags, const char *devname, void *dev_id)
+int request_irq(unsigned int irq,
+		irqreturn_t (*handler) (int, void *, struct pt_regs *),
+		unsigned long flags, const char *devname, void *dev_id)
 {
 	struct irq_node *node;
 	int res;
@@ -218,13 +238,15 @@ int cpu_request_irq(unsigned int irq,
 	return res;
 }
 
-void cpu_free_irq(unsigned int irq, void *dev_id)
+EXPORT_SYMBOL(request_irq);
+
+void free_irq(unsigned int irq, void *dev_id)
 {
 	struct irq_controller *contr;
 	struct irq_node **p, *node;
 	unsigned long flags;
 
-	if (irq >= SYS_IRQS || !(contr = irq_controller[irq])) {
+	if (irq >= NR_IRQS || !(contr = irq_controller[irq])) {
 		printk("%s: Incorrect IRQ %d\n", __FUNCTION__, irq);
 		return;
 	}
@@ -245,16 +267,69 @@ void cpu_free_irq(unsigned int irq, void
 		printk("%s: Removing probably wrong IRQ %d\n",
 		       __FUNCTION__, irq);
 
-	if (!irq_list[irq])
-		contr->shutdown(irq);
+	if (!irq_list[irq]) {
+		if (contr->shutdown)
+			contr->shutdown(irq);
+		else
+			contr->disable(irq);
+	}
+
+	spin_unlock_irqrestore(&contr->lock, flags);
+}
+
+EXPORT_SYMBOL(free_irq);
+
+void enable_irq(unsigned int irq)
+{
+	struct irq_controller *contr;
+	unsigned long flags;
+
+	if (irq >= NR_IRQS || !(contr = irq_controller[irq])) {
+		printk("%s: Incorrect IRQ %d\n",
+		       __FUNCTION__, irq);
+		return;
+	}
+
+	spin_lock_irqsave(&contr->lock, flags);
+	if (irq_depth[irq]) {
+		if (!--irq_depth[irq]) {
+			if (contr->enable)
+				contr->enable(irq);
+		}
+	} else
+		WARN_ON(1);
+	spin_unlock_irqrestore(&contr->lock, flags);
+}
+
+EXPORT_SYMBOL(enable_irq);
 
+void disable_irq(unsigned int irq)
+{
+	struct irq_controller *contr;
+	unsigned long flags;
+
+	if (irq >= NR_IRQS || !(contr = irq_controller[irq])) {
+		printk("%s: Incorrect IRQ %d\n",
+		       __FUNCTION__, irq);
+		return;
+	}
+
+	spin_lock_irqsave(&contr->lock, flags);
+	if (!irq_depth[irq]++) {
+		if (contr->disable)
+			contr->disable(irq);
+	}
 	spin_unlock_irqrestore(&contr->lock, flags);
 }
 
+EXPORT_SYMBOL(disable_irq);
+
 int m68k_irq_startup(unsigned int irq)
 {
 	if (irq <= IRQ_AUTO_7)
 		vectors[VEC_SPUR + irq] = auto_inthandler;
+	else
+		vectors[m68k_first_user_vec + irq - IRQ_USER] = user_inthandler;
 	return 0;
 }
 
@@ -262,6 +337,8 @@ void m68k_irq_shutdown(unsigned int irq)
 {
 	if (irq <= IRQ_AUTO_7)
 		vectors[VEC_SPUR + irq] = bad_inthandler;
+	else
+		vectors[m68k_first_user_vec + irq - IRQ_USER] = bad_inthandler;
 }
 
 
@@ -292,28 +369,16 @@ #endif
 
 EXPORT_SYMBOL(probe_irq_off);
 
-static void dummy_enable_irq(unsigned int irq)
+unsigned int irq_canonicalize(unsigned int irq)
 {
-	printk("calling uninitialized enable_irq()\n");
-}
-
-static void dummy_disable_irq(unsigned int irq)
-{
-	printk("calling uninitialized disable_irq()\n");
-}
-
-static int dummy_request_irq(unsigned int irq,
-		irqreturn_t (*handler) (int, void *, struct pt_regs *),
-		unsigned long flags, const char *devname, void *dev_id)
-{
-	printk("calling uninitialized request_irq()\n");
-	return 0;
+#ifdef CONFIG_Q40
+	if (MACH_IS_Q40 && irq == 11)
+		irq = 10;
+#endif
+	return irq;
 }
 
-static void dummy_free_irq(unsigned int irq, void *dev_id)
-{
-	printk("calling uninitialized disable_irq()\n");
-}
+EXPORT_SYMBOL(irq_canonicalize);
 
 asmlinkage void m68k_handle_int(unsigned int irq, struct pt_regs *regs)
 {
@@ -340,15 +405,14 @@ int show_interrupts(struct seq_file *p, 
 	int i = *(loff_t *) v;
 
 	/* autovector interrupts */
-	if (i < SYS_IRQS && irq_list[i]) {
+	if (irq_list[i]) {
 		contr = irq_controller[i];
 		node = irq_list[i];
-		seq_printf(p, "%s %u: %10u %s", contr->name, i, kstat_cpu(0).irqs[i], node->devname);
+		seq_printf(p, "%-8s %3u: %10u %s", contr->name, i, kstat_cpu(0).irqs[i], node->devname);
 		while ((node = node->next))
 			seq_printf(p, ", %s", node->devname);
 		seq_puts(p, "\n");
-	} else if (i == SYS_IRQS)
-		mach_get_irq_list(p, v);
+	}
 	return 0;
 }
 
diff --git a/arch/m68k/kernel/m68k_ksyms.c b/arch/m68k/kernel/m68k_ksyms.c
index 5b7952e..1f5e1b5 100644
--- a/arch/m68k/kernel/m68k_ksyms.c
+++ b/arch/m68k/kernel/m68k_ksyms.c
@@ -57,8 +57,6 @@ EXPORT_SYMBOL(dump_thread);
 EXPORT_SYMBOL(strnlen);
 EXPORT_SYMBOL(strrchr);
 EXPORT_SYMBOL(strstr);
-EXPORT_SYMBOL(enable_irq);
-EXPORT_SYMBOL(disable_irq);
 EXPORT_SYMBOL(kernel_thread);
 #ifdef CONFIG_VME
 EXPORT_SYMBOL(vme_brdtype);
diff --git a/arch/m68k/kernel/setup.c b/arch/m68k/kernel/setup.c
index 750d5b3..214a95f 100644
--- a/arch/m68k/kernel/setup.c
+++ b/arch/m68k/kernel/setup.c
@@ -68,11 +68,8 @@ char m68k_debug_device[6] = "";
 void (*mach_sched_init) (irqreturn_t (*handler)(int, void *, struct pt_regs *)) __initdata = NULL;
 /* machine dependent irq functions */
 void (*mach_init_IRQ) (void) __initdata = NULL;
-irqreturn_t (*(*mach_default_handler)[]) (int, void *, struct pt_regs *);
 void (*mach_get_model) (char *model);
 int (*mach_get_hardware_list) (char *buffer);
-int (*mach_get_irq_list) (struct seq_file *, void *);
-irqreturn_t (*mach_process_int) (int, struct pt_regs *);
 /* machine dependent timer functions */
 unsigned long (*mach_gettimeoffset) (void);
 int (*mach_hwclk) (int, struct rtc_time*);
diff --git a/arch/m68k/kernel/traps.c b/arch/m68k/kernel/traps.c
index b19b951..e86de7b 100644
--- a/arch/m68k/kernel/traps.c
+++ b/arch/m68k/kernel/traps.c
@@ -87,16 +87,15 @@ void __init trap_init (void)
 {
 	int i;
 
-	vectors[VEC_SPUR] = bad_inthandler;
-	for (i = VEC_INT1; i <= VEC_INT7; i++)
-		vectors[i] = auto_inthandler;
+	for (i = VEC_SPUR; i <= VEC_INT7; i++)
+		vectors[i] = bad_inthandler;
 
 	for (i = 0; i < VEC_USER; i++)
 		if (!vectors[i])
 			vectors[i] = trap;
 
 	for (i = VEC_USER; i < 256; i++)
-		vectors[i] = mach_inthandler;
+		vectors[i] = bad_inthandler;
 
 #ifdef CONFIG_M68KFPU_EMU
 	if (FPU_IS_EMU)
diff --git a/include/asm-m68k/irq.h b/include/asm-m68k/irq.h
index 7fa8733..f4ae7d8 100644
--- a/include/asm-m68k/irq.h
+++ b/include/asm-m68k/irq.h
@@ -1,25 +1,30 @@
 #ifndef _M68K_IRQ_H_
 #define _M68K_IRQ_H_
 
+#include <linux/linkage.h>
 #include <linux/hardirq.h>
 #include <linux/spinlock_types.h>
 
 /*
- * # of m68k auto vector interrupts
- */
-
-#define SYS_IRQS 8
-
-/*
  * This should be the same as the max(NUM_X_SOURCES) for all the
  * different m68k hosts compiled into the kernel.
  * Currently the Atari has 72 and the Amiga 24, but if both are
  * supported in the kernel it is better to make room for 72.
  */
-#if defined(CONFIG_ATARI) || defined(CONFIG_MAC)
-#define NR_IRQS (72+SYS_IRQS)
+#if defined(CONFIG_VME) || defined(CONFIG_SUN3) || defined(CONFIG_SUN3X)
+#define NR_IRQS 200
+#elif defined(CONFIG_ATARI) || defined(CONFIG_MAC)
+#define NR_IRQS 72
+#elif defined(CONFIG_Q40)
+#define NR_IRQS	43
+#elif defined(CONFIG_AMIGA)
+#define NR_IRQS	32
+#elif defined(CONFIG_APOLLO)
+#define NR_IRQS	24
+#elif defined(CONFIG_HP300)
+#define NR_IRQS	8
 #else
-#define NR_IRQS (24+SYS_IRQS)
+#error unknown nr of irqs
 #endif
 
 /*
@@ -53,39 +58,13 @@ #define IRQ_AUTO_7	7	/* level 7 interrup
 
 #define IRQ_USER	8
 
-static __inline__ int irq_canonicalize(int irq)
-{
-	return irq;
-}
-
-/*
- * Machine specific interrupt sources.
- *
- * Adding an interrupt service routine for a source with this bit
- * set indicates a special machine specific interrupt source.
- * The machine specific files define these sources.
- *
- * The IRQ_MACHSPEC bit is now gone - the only thing it did was to
- * introduce unnecessary overhead.
- *
- * All interrupt handling is actually machine specific so it is better
- * to use function pointers, as used by the Sparc port, and select the
- * interrupt handling functions when initializing the kernel. This way
- * we save some unnecessary overhead at run-time.
- *                                                      01/11/97 - Jes
- */
-
-extern void (*enable_irq)(unsigned int);
-extern void (*disable_irq)(unsigned int);
+extern unsigned int irq_canonicalize(unsigned int irq);
+extern void enable_irq(unsigned int);
+extern void disable_irq(unsigned int);
 #define disable_irq_nosync	disable_irq
 
 struct pt_regs;
 
-extern int cpu_request_irq(unsigned int,
-			   int (*)(int, void *, struct pt_regs *),
-			   unsigned long, const char *, void *);
-extern void cpu_free_irq(unsigned int, void *);
-
 /*
  * various flags for request_irq() - the Amiga now uses the standard
  * mechanism like all other architectures - SA_INTERRUPT and SA_SHIRQ
@@ -133,12 +112,16 @@ struct irq_controller {
 extern int m68k_irq_startup(unsigned int);
 extern void m68k_irq_shutdown(unsigned int);
 
-/* count of spurious interrupts */
-extern volatile unsigned int num_spurious;
-
 /*
  * This function returns a new irq_node_t
  */
 extern irq_node_t *new_irq_node(void);
 
+extern void m68k_setup_auto_interrupt(void (*handler)(unsigned int, struct pt_regs *));
+extern void m68k_setup_user_interrupt(unsigned int vec, unsigned int cnt,
+				      void (*handler)(unsigned int, struct pt_regs *));
+extern void m68k_setup_irq_controller(struct irq_controller *, unsigned int, unsigned int);
+
+asmlinkage void m68k_handle_int(unsigned int, struct pt_regs *);
+
 #endif /* _M68K_IRQ_H_ */
diff --git a/include/asm-m68k/machdep.h b/include/asm-m68k/machdep.h
index 7d3fee3..df898f2 100644
--- a/include/asm-m68k/machdep.h
+++ b/include/asm-m68k/machdep.h
@@ -13,14 +13,8 @@ struct buffer_head;
 extern void (*mach_sched_init) (irqreturn_t (*handler)(int, void *, struct pt_regs *));
 /* machine dependent irq functions */
 extern void (*mach_init_IRQ) (void);
-extern irqreturn_t (*(*mach_default_handler)[]) (int, void *, struct pt_regs *);
-extern int (*mach_request_irq) (unsigned int irq, irqreturn_t (*handler)(int, void *, struct pt_regs *),
-                                unsigned long flags, const char *devname, void *dev_id);
-extern void (*mach_free_irq) (unsigned int irq, void *dev_id);
 extern void (*mach_get_model) (char *model);
 extern int (*mach_get_hardware_list) (char *buffer);
-extern int (*mach_get_irq_list) (struct seq_file *p, void *v);
-extern irqreturn_t (*mach_process_int) (int irq, struct pt_regs *fp);
 /* machine dependent timer functions */
 extern unsigned long (*mach_gettimeoffset)(void);
 extern int (*mach_hwclk)(int, struct rtc_time*);
diff --git a/include/asm-m68k/traps.h b/include/asm-m68k/traps.h
index 7715194..8caef25 100644
--- a/include/asm-m68k/traps.h
+++ b/include/asm-m68k/traps.h
@@ -19,7 +19,7 @@ #include <asm/ptrace.h>
 typedef void (*e_vector)(void);
 
 asmlinkage void auto_inthandler(void);
-asmlinkage void mach_inthandler(void);
+asmlinkage void user_inthandler(void);
 asmlinkage void bad_inthandler(void);
 
 extern e_vector vectors[];
-- 
1.3.3

--