Support for Toshiba's RBHMA4500 eval board for the TX4938.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/tx4938/common/irq.c b/arch/mips/tx4938/common/irq.c
new file mode 100644
index 0000000..4f90d7f
--- /dev/null
+++ b/arch/mips/tx4938/common/irq.c
@@ -0,0 +1,424 @@
+/*
+ * linux/arch/mps/tx4938/common/irq.c
+ *
+ * Common tx4938 irq handler
+ * Copyright (C) 2000-2001 Toshiba Corporation
+ *
+ * 2003-2005 (c) MontaVista Software, Inc. This file is licensed under the
+ * terms of the GNU General Public License version 2. This program is
+ * licensed "as is" without any warranty of any kind, whether express
+ * or implied.
+ *
+ * Support for TX4938 in 2.6 - Manish Lachwani (mlachwani@mvista.com)
+ */
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/kernel_stat.h>
+#include <linux/module.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/types.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/timex.h>
+#include <linux/slab.h>
+#include <linux/random.h>
+#include <linux/irq.h>
+#include <asm/bitops.h>
+#include <asm/bootinfo.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/mipsregs.h>
+#include <asm/system.h>
+#include <asm/tx4938/rbtx4938.h>
+
+/**********************************************************************************/
+/* Forwad definitions for all pic's                                               */
+/**********************************************************************************/
+
+static unsigned int tx4938_irq_cp0_startup(unsigned int irq);
+static void tx4938_irq_cp0_shutdown(unsigned int irq);
+static void tx4938_irq_cp0_enable(unsigned int irq);
+static void tx4938_irq_cp0_disable(unsigned int irq);
+static void tx4938_irq_cp0_mask_and_ack(unsigned int irq);
+static void tx4938_irq_cp0_end(unsigned int irq);
+
+static unsigned int tx4938_irq_pic_startup(unsigned int irq);
+static void tx4938_irq_pic_shutdown(unsigned int irq);
+static void tx4938_irq_pic_enable(unsigned int irq);
+static void tx4938_irq_pic_disable(unsigned int irq);
+static void tx4938_irq_pic_mask_and_ack(unsigned int irq);
+static void tx4938_irq_pic_end(unsigned int irq);
+
+/**********************************************************************************/
+/* Kernel structs for all pic's                                                   */
+/**********************************************************************************/
+DEFINE_SPINLOCK(tx4938_cp0_lock);
+DEFINE_SPINLOCK(tx4938_pic_lock);
+
+#define TX4938_CP0_NAME "TX4938-CP0"
+static struct hw_interrupt_type tx4938_irq_cp0_type = {
+	.typename = TX4938_CP0_NAME,
+	.startup = tx4938_irq_cp0_startup,
+	.shutdown = tx4938_irq_cp0_shutdown,
+	.enable = tx4938_irq_cp0_enable,
+	.disable = tx4938_irq_cp0_disable,
+	.ack = tx4938_irq_cp0_mask_and_ack,
+	.end = tx4938_irq_cp0_end,
+	.set_affinity = NULL
+};
+
+#define TX4938_PIC_NAME "TX4938-PIC"
+static struct hw_interrupt_type tx4938_irq_pic_type = {
+	.typename = TX4938_PIC_NAME,
+	.startup = tx4938_irq_pic_startup,
+	.shutdown = tx4938_irq_pic_shutdown,
+	.enable = tx4938_irq_pic_enable,
+	.disable = tx4938_irq_pic_disable,
+	.ack = tx4938_irq_pic_mask_and_ack,
+	.end = tx4938_irq_pic_end,
+	.set_affinity = NULL
+};
+
+static struct irqaction tx4938_irq_pic_action = {
+	.handler = no_action,
+	.flags = 0,
+	.mask = CPU_MASK_NONE,
+	.name = TX4938_PIC_NAME
+};
+
+/**********************************************************************************/
+/* Functions for cp0                                                              */
+/**********************************************************************************/
+
+#define tx4938_irq_cp0_mask(irq) ( 1 << ( irq-TX4938_IRQ_CP0_BEG+8 ) )
+
+static void __init
+tx4938_irq_cp0_init(void)
+{
+	int i;
+
+	for (i = TX4938_IRQ_CP0_BEG; i <= TX4938_IRQ_CP0_END; i++) {
+		irq_desc[i].status = IRQ_DISABLED;
+		irq_desc[i].action = 0;
+		irq_desc[i].depth = 1;
+		irq_desc[i].handler = &tx4938_irq_cp0_type;
+	}
+
+	return;
+}
+
+static unsigned int
+tx4938_irq_cp0_startup(unsigned int irq)
+{
+	tx4938_irq_cp0_enable(irq);
+
+	return (0);
+}
+
+static void
+tx4938_irq_cp0_shutdown(unsigned int irq)
+{
+	tx4938_irq_cp0_disable(irq);
+}
+
+static void
+tx4938_irq_cp0_enable(unsigned int irq)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&tx4938_cp0_lock, flags);
+
+	set_c0_status(tx4938_irq_cp0_mask(irq));
+
+	spin_unlock_irqrestore(&tx4938_cp0_lock, flags);
+}
+
+static void
+tx4938_irq_cp0_disable(unsigned int irq)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&tx4938_cp0_lock, flags);
+
+	clear_c0_status(tx4938_irq_cp0_mask(irq));
+
+	spin_unlock_irqrestore(&tx4938_cp0_lock, flags);
+
+	return;
+}
+
+static void
+tx4938_irq_cp0_mask_and_ack(unsigned int irq)
+{
+	tx4938_irq_cp0_disable(irq);
+
+	return;
+}
+
+static void
+tx4938_irq_cp0_end(unsigned int irq)
+{
+	if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS))) {
+		tx4938_irq_cp0_enable(irq);
+	}
+
+	return;
+}
+
+/**********************************************************************************/
+/* Functions for pic                                                              */
+/**********************************************************************************/
+
+u32
+tx4938_irq_pic_addr(int irq)
+{
+	/* MVMCP -- need to formulize this */
+	irq -= TX4938_IRQ_PIC_BEG;
+
+	switch (irq) {
+	case 17:
+	case 16:
+	case 1:
+	case 0:{
+			return (TX4938_MKA(TX4938_IRC_IRLVL0));
+		}
+	case 19:
+	case 18:
+	case 3:
+	case 2:{
+			return (TX4938_MKA(TX4938_IRC_IRLVL1));
+		}
+	case 21:
+	case 20:
+	case 5:
+	case 4:{
+			return (TX4938_MKA(TX4938_IRC_IRLVL2));
+		}
+	case 23:
+	case 22:
+	case 7:
+	case 6:{
+			return (TX4938_MKA(TX4938_IRC_IRLVL3));
+		}
+	case 25:
+	case 24:
+	case 9:
+	case 8:{
+			return (TX4938_MKA(TX4938_IRC_IRLVL4));
+		}
+	case 27:
+	case 26:
+	case 11:
+	case 10:{
+			return (TX4938_MKA(TX4938_IRC_IRLVL5));
+		}
+	case 29:
+	case 28:
+	case 13:
+	case 12:{
+			return (TX4938_MKA(TX4938_IRC_IRLVL6));
+		}
+	case 31:
+	case 30:
+	case 15:
+	case 14:{
+			return (TX4938_MKA(TX4938_IRC_IRLVL7));
+		}
+	}
+
+	return (0);
+}
+
+u32
+tx4938_irq_pic_mask(int irq)
+{
+	/* MVMCP -- need to formulize this */
+	irq -= TX4938_IRQ_PIC_BEG;
+
+	switch (irq) {
+	case 31:
+	case 29:
+	case 27:
+	case 25:
+	case 23:
+	case 21:
+	case 19:
+	case 17:{
+			return (0x07000000);
+		}
+	case 30:
+	case 28:
+	case 26:
+	case 24:
+	case 22:
+	case 20:
+	case 18:
+	case 16:{
+			return (0x00070000);
+		}
+	case 15:
+	case 13:
+	case 11:
+	case 9:
+	case 7:
+	case 5:
+	case 3:
+	case 1:{
+			return (0x00000700);
+		}
+	case 14:
+	case 12:
+	case 10:
+	case 8:
+	case 6:
+	case 4:
+	case 2:
+	case 0:{
+			return (0x00000007);
+		}
+	}
+	return (0x00000000);
+}
+
+static void
+tx4938_irq_pic_modify(unsigned pic_reg, unsigned clr_bits, unsigned set_bits)
+{
+	unsigned long val = 0;
+
+	val = TX4938_RD(pic_reg);
+	val &= (~clr_bits);
+	val |= (set_bits);
+	TX4938_WR(pic_reg, val);
+	mmiowb();
+	TX4938_RD(pic_reg);
+
+	return;
+}
+
+static void __init
+tx4938_irq_pic_init(void)
+{
+	unsigned long flags;
+	int i;
+
+	for (i = TX4938_IRQ_PIC_BEG; i <= TX4938_IRQ_PIC_END; i++) {
+		irq_desc[i].status = IRQ_DISABLED;
+		irq_desc[i].action = 0;
+		irq_desc[i].depth = 2;
+		irq_desc[i].handler = &tx4938_irq_pic_type;
+	}
+
+	setup_irq(TX4938_IRQ_NEST_PIC_ON_CP0, &tx4938_irq_pic_action);
+
+	spin_lock_irqsave(&tx4938_pic_lock, flags);
+
+	TX4938_WR(0xff1ff640, 0x6);	/* irq level mask -- only accept hightest */
+	TX4938_WR(0xff1ff600, TX4938_RD(0xff1ff600) | 0x1);	/* irq enable */
+
+	spin_unlock_irqrestore(&tx4938_pic_lock, flags);
+
+	return;
+}
+
+static unsigned int
+tx4938_irq_pic_startup(unsigned int irq)
+{
+	tx4938_irq_pic_enable(irq);
+
+	return (0);
+}
+
+static void
+tx4938_irq_pic_shutdown(unsigned int irq)
+{
+	tx4938_irq_pic_disable(irq);
+
+	return;
+}
+
+static void
+tx4938_irq_pic_enable(unsigned int irq)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&tx4938_pic_lock, flags);
+
+	tx4938_irq_pic_modify(tx4938_irq_pic_addr(irq), 0,
+			      tx4938_irq_pic_mask(irq));
+
+	spin_unlock_irqrestore(&tx4938_pic_lock, flags);
+
+	return;
+}
+
+static void
+tx4938_irq_pic_disable(unsigned int irq)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&tx4938_pic_lock, flags);
+
+	tx4938_irq_pic_modify(tx4938_irq_pic_addr(irq),
+			      tx4938_irq_pic_mask(irq), 0);
+
+	spin_unlock_irqrestore(&tx4938_pic_lock, flags);
+
+	return;
+}
+
+static void
+tx4938_irq_pic_mask_and_ack(unsigned int irq)
+{
+	tx4938_irq_pic_disable(irq);
+
+	return;
+}
+
+static void
+tx4938_irq_pic_end(unsigned int irq)
+{
+	if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS))) {
+		tx4938_irq_pic_enable(irq);
+	}
+
+	return;
+}
+
+/**********************************************************************************/
+/* Main init functions                                                            */
+/**********************************************************************************/
+
+void __init
+tx4938_irq_init(void)
+{
+	extern asmlinkage void tx4938_irq_handler(void);
+
+	tx4938_irq_cp0_init();
+	tx4938_irq_pic_init();
+	set_except_vector(0, tx4938_irq_handler);
+
+	return;
+}
+
+int
+tx4938_irq_nested(void)
+{
+	int sw_irq = 0;
+	u32 level2;
+
+	level2 = TX4938_RD(0xff1ff6a0);
+	if ((level2 & 0x10000) == 0) {
+		level2 &= 0x1f;
+		sw_irq = TX4938_IRQ_PIC_BEG + level2;
+		if (sw_irq == 26) {
+			{
+				extern int toshiba_rbtx4938_irq_nested(int sw_irq);
+				sw_irq = toshiba_rbtx4938_irq_nested(sw_irq);
+			}
+		}
+	}
+
+	wbflush();
+	return (sw_irq);
+}