1 /*
2  * Copyright 2001 MontaVista Software Inc.
3  * Author: MontaVista Software, Inc.
4  *              ahennessy@mvista.com
5  *
6  * This file is subject to the terms and conditions of the GNU General Public
7  * License.  See the file "COPYING" in the main directory of this archive
8  * for more details.
9  *
10  * Copyright (C) 2000-2001 Toshiba Corporation
11  *
12  *  This program is free software; you can redistribute  it and/or modify it
13  *  under  the terms of  the GNU General  Public License as published by the
14  *  Free Software Foundation;  either version 2 of the  License, or (at your
15  *  option) any later version.
16  *
17  *  THIS  SOFTWARE  IS PROVIDED   ``AS  IS'' AND   ANY  EXPRESS OR IMPLIED
18  *  WARRANTIES,   INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
19  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
20  *  NO  EVENT  SHALL   THE AUTHOR  BE    LIABLE FOR ANY   DIRECT, INDIRECT,
21  *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  *  NOT LIMITED   TO, PROCUREMENT OF  SUBSTITUTE GOODS  OR SERVICES; LOSS OF
23  *  USE, DATA,  OR PROFITS; OR  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
24  *  ANY THEORY OF LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT
25  *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  *
28  *  You should have received a copy of the  GNU General Public License along
29  *  with this program; if not, write  to the Free Software Foundation, Inc.,
30  *  675 Mass Ave, Cambridge, MA 02139, USA.
31  */
32 #include <linux/init.h>
33 #include <linux/types.h>
34 #include <linux/interrupt.h>
35 #include <linux/irq.h>
36 
37 #include <asm/io.h>
38 #include <asm/mipsregs.h>
39 #include <asm/txx9/generic.h>
40 #include <asm/txx9/jmr3927.h>
41 
42 #if JMR3927_IRQ_END > NR_IRQS
43 #error JMR3927_IRQ_END > NR_IRQS
44 #endif
45 
46 /*
47  * CP0_STATUS is a thread's resource (saved/restored on context switch).
48  * So disable_irq/enable_irq MUST handle IOC/IRC registers.
49  */
mask_irq_ioc(struct irq_data * d)50 static void mask_irq_ioc(struct irq_data *d)
51 {
52 	/* 0: mask */
53 	unsigned int irq_nr = d->irq - JMR3927_IRQ_IOC;
54 	unsigned char imask = jmr3927_ioc_reg_in(JMR3927_IOC_INTM_ADDR);
55 	unsigned int bit = 1 << irq_nr;
56 	jmr3927_ioc_reg_out(imask & ~bit, JMR3927_IOC_INTM_ADDR);
57 	/* flush write buffer */
58 	(void)jmr3927_ioc_reg_in(JMR3927_IOC_REV_ADDR);
59 }
unmask_irq_ioc(struct irq_data * d)60 static void unmask_irq_ioc(struct irq_data *d)
61 {
62 	/* 0: mask */
63 	unsigned int irq_nr = d->irq - JMR3927_IRQ_IOC;
64 	unsigned char imask = jmr3927_ioc_reg_in(JMR3927_IOC_INTM_ADDR);
65 	unsigned int bit = 1 << irq_nr;
66 	jmr3927_ioc_reg_out(imask | bit, JMR3927_IOC_INTM_ADDR);
67 	/* flush write buffer */
68 	(void)jmr3927_ioc_reg_in(JMR3927_IOC_REV_ADDR);
69 }
70 
jmr3927_ioc_irqroute(void)71 static int jmr3927_ioc_irqroute(void)
72 {
73 	unsigned char istat = jmr3927_ioc_reg_in(JMR3927_IOC_INTS2_ADDR);
74 	int i;
75 
76 	for (i = 0; i < JMR3927_NR_IRQ_IOC; i++) {
77 		if (istat & (1 << i))
78 			return JMR3927_IRQ_IOC + i;
79 	}
80 	return -1;
81 }
82 
jmr3927_irq_dispatch(int pending)83 static int jmr3927_irq_dispatch(int pending)
84 {
85 	int irq;
86 
87 	if ((pending & CAUSEF_IP7) == 0)
88 		return -1;
89 	irq = (pending >> CAUSEB_IP2) & 0x0f;
90 	irq += JMR3927_IRQ_IRC;
91 	if (irq == JMR3927_IRQ_IOCINT)
92 		irq = jmr3927_ioc_irqroute();
93 	return irq;
94 }
95 
96 static struct irq_chip jmr3927_irq_ioc = {
97 	.name = "jmr3927_ioc",
98 	.irq_mask = mask_irq_ioc,
99 	.irq_unmask = unmask_irq_ioc,
100 };
101 
jmr3927_irq_setup(void)102 void __init jmr3927_irq_setup(void)
103 {
104 	int i;
105 
106 	txx9_irq_dispatch = jmr3927_irq_dispatch;
107 	/* Now, interrupt control disabled, */
108 	/* all IRC interrupts are masked, */
109 	/* all IRC interrupt mode are Low Active. */
110 
111 	/* mask all IOC interrupts */
112 	jmr3927_ioc_reg_out(0, JMR3927_IOC_INTM_ADDR);
113 	/* setup IOC interrupt mode (SOFT:High Active, Others:Low Active) */
114 	jmr3927_ioc_reg_out(JMR3927_IOC_INTF_SOFT, JMR3927_IOC_INTP_ADDR);
115 
116 	/* clear PCI Soft interrupts */
117 	jmr3927_ioc_reg_out(0, JMR3927_IOC_INTS1_ADDR);
118 	/* clear PCI Reset interrupts */
119 	jmr3927_ioc_reg_out(0, JMR3927_IOC_RESET_ADDR);
120 
121 	tx3927_irq_init();
122 	for (i = JMR3927_IRQ_IOC; i < JMR3927_IRQ_IOC + JMR3927_NR_IRQ_IOC; i++)
123 		irq_set_chip_and_handler(i, &jmr3927_irq_ioc,
124 					 handle_level_irq);
125 
126 	/* setup IOC interrupt 1 (PCI, MODEM) */
127 	irq_set_chained_handler(JMR3927_IRQ_IOCINT, handle_simple_irq);
128 }
129