aboutsummaryrefslogtreecommitdiffstats
path: root/arch/mips/kernel/cevt-sb1250.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/mips/kernel/cevt-sb1250.c')
-rw-r--r--arch/mips/kernel/cevt-sb1250.c148
1 files changed, 148 insertions, 0 deletions
diff --git a/arch/mips/kernel/cevt-sb1250.c b/arch/mips/kernel/cevt-sb1250.c
new file mode 100644
index 000000000000..e2029d0fc39b
--- /dev/null
+++ b/arch/mips/kernel/cevt-sb1250.c
@@ -0,0 +1,148 @@
1/*
2 * Copyright (C) 2000, 2001 Broadcom Corporation
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version 2
7 * of the License, or (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
17 */
18#include <linux/clockchips.h>
19#include <linux/interrupt.h>
20#include <linux/percpu.h>
21
22#include <asm/addrspace.h>
23#include <asm/io.h>
24#include <asm/time.h>
25
26#include <asm/sibyte/sb1250.h>
27#include <asm/sibyte/sb1250_regs.h>
28#include <asm/sibyte/sb1250_int.h>
29#include <asm/sibyte/sb1250_scd.h>
30
31#define IMR_IP2_VAL K_INT_MAP_I0
32#define IMR_IP3_VAL K_INT_MAP_I1
33#define IMR_IP4_VAL K_INT_MAP_I2
34
35/*
36 * The general purpose timer ticks at 1MHz independent if
37 * the rest of the system
38 */
39static void sibyte_set_mode(enum clock_event_mode mode,
40 struct clock_event_device *evt)
41{
42 unsigned int cpu = smp_processor_id();
43 void __iomem *cfg, *init;
44
45 cfg = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG));
46 init = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_INIT));
47
48 switch (mode) {
49 case CLOCK_EVT_MODE_PERIODIC:
50 __raw_writeq(0, cfg);
51 __raw_writeq((V_SCD_TIMER_FREQ / HZ) - 1, init);
52 __raw_writeq(M_SCD_TIMER_ENABLE | M_SCD_TIMER_MODE_CONTINUOUS,
53 cfg);
54 break;
55
56 case CLOCK_EVT_MODE_ONESHOT:
57 /* Stop the timer until we actually program a shot */
58 case CLOCK_EVT_MODE_SHUTDOWN:
59 __raw_writeq(0, cfg);
60 break;
61
62 case CLOCK_EVT_MODE_UNUSED: /* shuddup gcc */
63 case CLOCK_EVT_MODE_RESUME:
64 ;
65 }
66}
67
68static int sibyte_next_event(unsigned long delta, struct clock_event_device *cd)
69{
70 unsigned int cpu = smp_processor_id();
71 void __iomem *cfg, *init;
72
73 cfg = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG));
74 init = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_INIT));
75
76 __raw_writeq(delta - 1, init);
77 __raw_writeq(M_SCD_TIMER_ENABLE, cfg);
78
79 return 0;
80}
81
82static irqreturn_t sibyte_counter_handler(int irq, void *dev_id)
83{
84 unsigned int cpu = smp_processor_id();
85 struct clock_event_device *cd = dev_id;
86 void __iomem *cfg;
87 unsigned long tmode;
88
89 if (cd->mode == CLOCK_EVT_MODE_PERIODIC)
90 tmode = M_SCD_TIMER_ENABLE | M_SCD_TIMER_MODE_CONTINUOUS;
91 else
92 tmode = 0;
93
94 /* ACK interrupt */
95 cfg = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG));
96 ____raw_writeq(tmode, cfg);
97
98 cd->event_handler(cd);
99
100 return IRQ_HANDLED;
101}
102
103static DEFINE_PER_CPU(struct clock_event_device, sibyte_hpt_clockevent);
104static DEFINE_PER_CPU(struct irqaction, sibyte_hpt_irqaction);
105static DEFINE_PER_CPU(char [18], sibyte_hpt_name);
106
107void __cpuinit sb1250_clockevent_init(void)
108{
109 unsigned int cpu = smp_processor_id();
110 unsigned int irq = K_INT_TIMER_0 + cpu;
111 struct irqaction *action = &per_cpu(sibyte_hpt_irqaction, cpu);
112 struct clock_event_device *cd = &per_cpu(sibyte_hpt_clockevent, cpu);
113 unsigned char *name = per_cpu(sibyte_hpt_name, cpu);
114
115 /* Only have 4 general purpose timers, and we use last one as hpt */
116 BUG_ON(cpu > 2);
117
118 sprintf(name, "sb1250-counter-%d", cpu);
119 cd->name = name;
120 cd->features = CLOCK_EVT_FEAT_PERIODIC |
121 CLOCK_EVT_FEAT_ONESHOT;
122 clockevent_set_clock(cd, V_SCD_TIMER_FREQ);
123 cd->max_delta_ns = clockevent_delta2ns(0x7fffff, cd);
124 cd->min_delta_ns = clockevent_delta2ns(1, cd);
125 cd->rating = 200;
126 cd->irq = irq;
127 cd->cpumask = cpumask_of_cpu(cpu);
128 cd->set_next_event = sibyte_next_event;
129 cd->set_mode = sibyte_set_mode;
130 clockevents_register_device(cd);
131
132 sb1250_mask_irq(cpu, irq);
133
134 /*
135 * Map the timer interrupt to IP[4] of this cpu
136 */
137 __raw_writeq(IMR_IP4_VAL,
138 IOADDR(A_IMR_REGISTER(cpu, R_IMR_INTERRUPT_MAP_BASE) +
139 (irq << 3)));
140
141 sb1250_unmask_irq(cpu, irq);
142
143 action->handler = sibyte_counter_handler;
144 action->flags = IRQF_DISABLED | IRQF_PERCPU;
145 action->name = name;
146 action->dev_id = cd;
147 setup_irq(irq, action);
148}