aboutsummaryrefslogtreecommitdiff
path: root/arch/ppc64/kernel/iSeries_irq.c
blob: 41902e358e76a5ce9ecb7f0cb34a28122c7bb9fc (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
/*
 * This module supports the iSeries PCI bus interrupt handling
 * Copyright (C) 20yy  <Robert L Holtorf> <IBM Corp>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the:
 * Free Software Foundation, Inc.,
 * 59 Temple Place, Suite 330,
 * Boston, MA  02111-1307  USA
 *
 * Change Activity:
 *   Created, December 13, 2000 by Wayne Holm
 * End Change Activity
 */
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/threads.h>
#include <linux/smp.h>
#include <linux/param.h>
#include <linux/string.h>
#include <linux/bootmem.h>
#include <linux/ide.h>

#include <linux/irq.h>
#include <linux/spinlock.h>
#include <asm/ppcdebug.h>

#include <asm/iSeries/HvCallPci.h>
#include <asm/iSeries/HvCallXm.h>
#include <asm/iSeries/iSeries_irq.h>

/* This maps virtual irq numbers to real irqs */
unsigned int virt_irq_to_real_map[NR_IRQS];

/* The next available virtual irq number */
/* Note: the pcnet32 driver assumes irq numbers < 2 aren't valid. :( */
static int next_virtual_irq = 2;

/* This is called by init_IRQ.  set in ppc_md.init_IRQ by iSeries_setup.c */
void __init iSeries_init_IRQ(void)
{
	/* Register PCI event handler and open an event path */
	XmPciLpEvent_init();
}

#define REAL_IRQ_TO_BUS(irq)	((((irq) >> 6) & 0xff) + 1)
#define REAL_IRQ_TO_IDSEL(irq)	((((irq) >> 3) & 7) + 1)
#define REAL_IRQ_TO_FUNC(irq)	((irq) & 7)

/*
 * This will be called by device drivers (via enable_IRQ)
 * to enable INTA in the bridge interrupt status register.
 */
static void iSeries_enable_IRQ(unsigned int irq)
{
	u32 bus, deviceId, function, mask;
	const u32 subBus = 0;
	unsigned int rirq = virt_irq_to_real_map[irq];

	/* The IRQ has already been locked by the caller */
	bus = REAL_IRQ_TO_BUS(rirq);
	function = REAL_IRQ_TO_FUNC(rirq);
	deviceId = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;

	/* Unmask secondary INTA */
	mask = 0x80000000;
	HvCallPci_unmaskInterrupts(bus, subBus, deviceId, mask);
	PPCDBG(PPCDBG_BUSWALK, "iSeries_enable_IRQ 0x%02X.%02X.%02X 0x%04X\n",
			bus, subBus, deviceId, irq);
}

/* This is called by iSeries_activate_IRQs */
static unsigned int iSeries_startup_IRQ(unsigned int irq)
{
	u32 bus, deviceId, function, mask;
	const u32 subBus = 0;
	unsigned int rirq = virt_irq_to_real_map[irq];

	bus = REAL_IRQ_TO_BUS(rirq);
	function = REAL_IRQ_TO_FUNC(rirq);
	deviceId = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;

	/* Link the IRQ number to the bridge */
	HvCallXm_connectBusUnit(bus, subBus, deviceId, irq);

	/* Unmask bridge interrupts in the FISR */
	mask = 0x01010000 << function;
	HvCallPci_unmaskFisr(bus, subBus, deviceId, mask);
	iSeries_enable_IRQ(irq);
	return 0;
}

/*
 * This is called out of iSeries_fixup to activate interrupt
 * generation for usable slots
 */
void __init iSeries_activate_IRQs()
{
	int irq;
	unsigned long flags;

	for_each_irq (irq) {
		irq_desc_t *desc = get_irq_desc(irq);

		if (desc && desc->handler && desc->handler->startup) {
			spin_lock_irqsave(&desc->lock, flags);
			desc->handler->startup(irq);
			spin_unlock_irqrestore(&desc->lock, flags);
		}
	}
}

/*  this is not called anywhere currently */
static void iSeries_shutdown_IRQ(unsigned int irq)
{
	u32 bus, deviceId, function, mask;
	const u32 subBus = 0;
	unsigned int rirq = virt_irq_to_real_map[irq];

	/* irq should be locked by the caller */
	bus = REAL_IRQ_TO_BUS(rirq);
	function = REAL_IRQ_TO_FUNC(rirq);
	deviceId = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;

	/* Invalidate the IRQ number in the bridge */
	HvCallXm_connectBusUnit(bus, subBus, deviceId, 0);

	/* Mask bridge interrupts in the FISR */
	mask = 0x01010000 << function;
	HvCallPci_maskFisr(bus, subBus, deviceId, mask);
}

/*
 * This will be called by device drivers (via disable_IRQ)
 * to disable INTA in the bridge interrupt status register.
 */
static void iSeries_disable_IRQ(unsigned int irq)
{
	u32 bus, deviceId, function, mask;
	const u32 subBus = 0;
	unsigned int rirq = virt_irq_to_real_map[irq];

	/* The IRQ has already been locked by the caller */
	bus = REAL_IRQ_TO_BUS(rirq);
	function = REAL_IRQ_TO_FUNC(rirq);
	deviceId = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;

	/* Mask secondary INTA   */
	mask = 0x80000000;
	HvCallPci_maskInterrupts(bus, subBus, deviceId, mask);
	PPCDBG(PPCDBG_BUSWALK, "iSeries_disable_IRQ 0x%02X.%02X.%02X 0x%04X\n",
			bus, subBus, deviceId, irq);
}

/*
 * Need to define this so ppc_irq_dispatch_handler will NOT call
 * enable_IRQ at the end of interrupt handling.  However, this does
 * nothing because there is not enough information provided to do
 * the EOI HvCall.  This is done by XmPciLpEvent.c
 */
static void iSeries_end_IRQ(unsigned int irq)
{
}

static hw_irq_controller iSeries_IRQ_handler = {
	.typename = "iSeries irq controller",
	.startup = iSeries_startup_IRQ,
	.shutdown = iSeries_shutdown_IRQ,
	.enable = iSeries_enable_IRQ,
	.disable = iSeries_disable_IRQ,
	.end = iSeries_end_IRQ
};

/*
 * This is called out of iSeries_scan_slot to allocate an IRQ for an EADS slot
 * It calculates the irq value for the slot.
 * Note that subBusNumber is always 0 (at the moment at least).
 */
int __init iSeries_allocate_IRQ(HvBusNumber busNumber,
		HvSubBusNumber subBusNumber, HvAgentId deviceId)
{
	unsigned int realirq, virtirq;
	u8 idsel = (deviceId >> 4);
	u8 function = deviceId & 7;

	virtirq = next_virtual_irq++;
	realirq = ((busNumber - 1) << 6) + ((idsel - 1) << 3) + function;
	virt_irq_to_real_map[virtirq] = realirq;

	irq_desc[virtirq].handler = &iSeries_IRQ_handler;
	return virtirq;
}