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authorDavid S. Miller <davem@davemloft.net>2008-10-08 17:56:41 -0400
committerDavid S. Miller <davem@davemloft.net>2008-10-08 17:56:41 -0400
commit4dd565134ece7e5d528d4c5288879310c54419e9 (patch)
treee08910d2d0feae0c030f8f01acc9b03eb760ad9a /arch/mips/kernel/cevt-r4k.c
parent071d7ab6649eb34a873a53e71635186e9117101d (diff)
parent69849375d6b13e94d08cdc94b49b11fbab454a0e (diff)
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts: drivers/net/e1000e/ich8lan.c drivers/net/e1000e/netdev.c
Diffstat (limited to 'arch/mips/kernel/cevt-r4k.c')
-rw-r--r--arch/mips/kernel/cevt-r4k.c173
1 files changed, 48 insertions, 125 deletions
diff --git a/arch/mips/kernel/cevt-r4k.c b/arch/mips/kernel/cevt-r4k.c
index 24a2d907aa0d..4a4c59f2737a 100644
--- a/arch/mips/kernel/cevt-r4k.c
+++ b/arch/mips/kernel/cevt-r4k.c
@@ -12,6 +12,14 @@
12 12
13#include <asm/smtc_ipi.h> 13#include <asm/smtc_ipi.h>
14#include <asm/time.h> 14#include <asm/time.h>
15#include <asm/cevt-r4k.h>
16
17/*
18 * The SMTC Kernel for the 34K, 1004K, et. al. replaces several
19 * of these routines with SMTC-specific variants.
20 */
21
22#ifndef CONFIG_MIPS_MT_SMTC
15 23
16static int mips_next_event(unsigned long delta, 24static int mips_next_event(unsigned long delta,
17 struct clock_event_device *evt) 25 struct clock_event_device *evt)
@@ -19,60 +27,27 @@ static int mips_next_event(unsigned long delta,
19 unsigned int cnt; 27 unsigned int cnt;
20 int res; 28 int res;
21 29
22#ifdef CONFIG_MIPS_MT_SMTC
23 {
24 unsigned long flags, vpflags;
25 local_irq_save(flags);
26 vpflags = dvpe();
27#endif
28 cnt = read_c0_count(); 30 cnt = read_c0_count();
29 cnt += delta; 31 cnt += delta;
30 write_c0_compare(cnt); 32 write_c0_compare(cnt);
31 res = ((int)(read_c0_count() - cnt) > 0) ? -ETIME : 0; 33 res = ((int)(read_c0_count() - cnt) > 0) ? -ETIME : 0;
32#ifdef CONFIG_MIPS_MT_SMTC
33 evpe(vpflags);
34 local_irq_restore(flags);
35 }
36#endif
37 return res; 34 return res;
38} 35}
39 36
40static void mips_set_mode(enum clock_event_mode mode, 37#endif /* CONFIG_MIPS_MT_SMTC */
41 struct clock_event_device *evt) 38
39void mips_set_clock_mode(enum clock_event_mode mode,
40 struct clock_event_device *evt)
42{ 41{
43 /* Nothing to do ... */ 42 /* Nothing to do ... */
44} 43}
45 44
46static DEFINE_PER_CPU(struct clock_event_device, mips_clockevent_device); 45DEFINE_PER_CPU(struct clock_event_device, mips_clockevent_device);
47static int cp0_timer_irq_installed; 46int cp0_timer_irq_installed;
48 47
49/* 48#ifndef CONFIG_MIPS_MT_SMTC
50 * Timer ack for an R4k-compatible timer of a known frequency.
51 */
52static void c0_timer_ack(void)
53{
54 write_c0_compare(read_c0_compare());
55}
56 49
57/* 50irqreturn_t c0_compare_interrupt(int irq, void *dev_id)
58 * Possibly handle a performance counter interrupt.
59 * Return true if the timer interrupt should not be checked
60 */
61static inline int handle_perf_irq(int r2)
62{
63 /*
64 * The performance counter overflow interrupt may be shared with the
65 * timer interrupt (cp0_perfcount_irq < 0). If it is and a
66 * performance counter has overflowed (perf_irq() == IRQ_HANDLED)
67 * and we can't reliably determine if a counter interrupt has also
68 * happened (!r2) then don't check for a timer interrupt.
69 */
70 return (cp0_perfcount_irq < 0) &&
71 perf_irq() == IRQ_HANDLED &&
72 !r2;
73}
74
75static irqreturn_t c0_compare_interrupt(int irq, void *dev_id)
76{ 51{
77 const int r2 = cpu_has_mips_r2; 52 const int r2 = cpu_has_mips_r2;
78 struct clock_event_device *cd; 53 struct clock_event_device *cd;
@@ -93,12 +68,8 @@ static irqreturn_t c0_compare_interrupt(int irq, void *dev_id)
93 * interrupt. Being the paranoiacs we are we check anyway. 68 * interrupt. Being the paranoiacs we are we check anyway.
94 */ 69 */
95 if (!r2 || (read_c0_cause() & (1 << 30))) { 70 if (!r2 || (read_c0_cause() & (1 << 30))) {
96 c0_timer_ack(); 71 /* Clear Count/Compare Interrupt */
97#ifdef CONFIG_MIPS_MT_SMTC 72 write_c0_compare(read_c0_compare());
98 if (cpu_data[cpu].vpe_id)
99 goto out;
100 cpu = 0;
101#endif
102 cd = &per_cpu(mips_clockevent_device, cpu); 73 cd = &per_cpu(mips_clockevent_device, cpu);
103 cd->event_handler(cd); 74 cd->event_handler(cd);
104 } 75 }
@@ -107,65 +78,16 @@ out:
107 return IRQ_HANDLED; 78 return IRQ_HANDLED;
108} 79}
109 80
110static struct irqaction c0_compare_irqaction = { 81#endif /* Not CONFIG_MIPS_MT_SMTC */
82
83struct irqaction c0_compare_irqaction = {
111 .handler = c0_compare_interrupt, 84 .handler = c0_compare_interrupt,
112#ifdef CONFIG_MIPS_MT_SMTC
113 .flags = IRQF_DISABLED,
114#else
115 .flags = IRQF_DISABLED | IRQF_PERCPU, 85 .flags = IRQF_DISABLED | IRQF_PERCPU,
116#endif
117 .name = "timer", 86 .name = "timer",
118}; 87};
119 88
120#ifdef CONFIG_MIPS_MT_SMTC
121DEFINE_PER_CPU(struct clock_event_device, smtc_dummy_clockevent_device);
122
123static void smtc_set_mode(enum clock_event_mode mode,
124 struct clock_event_device *evt)
125{
126}
127
128static void mips_broadcast(cpumask_t mask)
129{
130 unsigned int cpu;
131
132 for_each_cpu_mask(cpu, mask)
133 smtc_send_ipi(cpu, SMTC_CLOCK_TICK, 0);
134}
135
136static void setup_smtc_dummy_clockevent_device(void)
137{
138 //uint64_t mips_freq = mips_hpt_^frequency;
139 unsigned int cpu = smp_processor_id();
140 struct clock_event_device *cd;
141 89
142 cd = &per_cpu(smtc_dummy_clockevent_device, cpu); 90void mips_event_handler(struct clock_event_device *dev)
143
144 cd->name = "SMTC";
145 cd->features = CLOCK_EVT_FEAT_DUMMY;
146
147 /* Calculate the min / max delta */
148 cd->mult = 0; //div_sc((unsigned long) mips_freq, NSEC_PER_SEC, 32);
149 cd->shift = 0; //32;
150 cd->max_delta_ns = 0; //clockevent_delta2ns(0x7fffffff, cd);
151 cd->min_delta_ns = 0; //clockevent_delta2ns(0x30, cd);
152
153 cd->rating = 200;
154 cd->irq = 17; //-1;
155// if (cpu)
156// cd->cpumask = CPU_MASK_ALL; // cpumask_of_cpu(cpu);
157// else
158 cd->cpumask = cpumask_of_cpu(cpu);
159
160 cd->set_mode = smtc_set_mode;
161
162 cd->broadcast = mips_broadcast;
163
164 clockevents_register_device(cd);
165}
166#endif
167
168static void mips_event_handler(struct clock_event_device *dev)
169{ 91{
170} 92}
171 93
@@ -177,7 +99,23 @@ static int c0_compare_int_pending(void)
177 return (read_c0_cause() >> cp0_compare_irq) & 0x100; 99 return (read_c0_cause() >> cp0_compare_irq) & 0x100;
178} 100}
179 101
180static int c0_compare_int_usable(void) 102/*
103 * Compare interrupt can be routed and latched outside the core,
104 * so a single execution hazard barrier may not be enough to give
105 * it time to clear as seen in the Cause register. 4 time the
106 * pipeline depth seems reasonably conservative, and empirically
107 * works better in configurations with high CPU/bus clock ratios.
108 */
109
110#define compare_change_hazard() \
111 do { \
112 irq_disable_hazard(); \
113 irq_disable_hazard(); \
114 irq_disable_hazard(); \
115 irq_disable_hazard(); \
116 } while (0)
117
118int c0_compare_int_usable(void)
181{ 119{
182 unsigned int delta; 120 unsigned int delta;
183 unsigned int cnt; 121 unsigned int cnt;
@@ -187,7 +125,7 @@ static int c0_compare_int_usable(void)
187 */ 125 */
188 if (c0_compare_int_pending()) { 126 if (c0_compare_int_pending()) {
189 write_c0_compare(read_c0_count()); 127 write_c0_compare(read_c0_count());
190 irq_disable_hazard(); 128 compare_change_hazard();
191 if (c0_compare_int_pending()) 129 if (c0_compare_int_pending())
192 return 0; 130 return 0;
193 } 131 }
@@ -196,7 +134,7 @@ static int c0_compare_int_usable(void)
196 cnt = read_c0_count(); 134 cnt = read_c0_count();
197 cnt += delta; 135 cnt += delta;
198 write_c0_compare(cnt); 136 write_c0_compare(cnt);
199 irq_disable_hazard(); 137 compare_change_hazard();
200 if ((int)(read_c0_count() - cnt) < 0) 138 if ((int)(read_c0_count() - cnt) < 0)
201 break; 139 break;
202 /* increase delta if the timer was already expired */ 140 /* increase delta if the timer was already expired */
@@ -205,11 +143,12 @@ static int c0_compare_int_usable(void)
205 while ((int)(read_c0_count() - cnt) <= 0) 143 while ((int)(read_c0_count() - cnt) <= 0)
206 ; /* Wait for expiry */ 144 ; /* Wait for expiry */
207 145
146 compare_change_hazard();
208 if (!c0_compare_int_pending()) 147 if (!c0_compare_int_pending())
209 return 0; 148 return 0;
210 149
211 write_c0_compare(read_c0_count()); 150 write_c0_compare(read_c0_count());
212 irq_disable_hazard(); 151 compare_change_hazard();
213 if (c0_compare_int_pending()) 152 if (c0_compare_int_pending())
214 return 0; 153 return 0;
215 154
@@ -219,6 +158,8 @@ static int c0_compare_int_usable(void)
219 return 1; 158 return 1;
220} 159}
221 160
161#ifndef CONFIG_MIPS_MT_SMTC
162
222int __cpuinit mips_clockevent_init(void) 163int __cpuinit mips_clockevent_init(void)
223{ 164{
224 uint64_t mips_freq = mips_hpt_frequency; 165 uint64_t mips_freq = mips_hpt_frequency;
@@ -229,17 +170,6 @@ int __cpuinit mips_clockevent_init(void)
229 if (!cpu_has_counter || !mips_hpt_frequency) 170 if (!cpu_has_counter || !mips_hpt_frequency)
230 return -ENXIO; 171 return -ENXIO;
231 172
232#ifdef CONFIG_MIPS_MT_SMTC
233 setup_smtc_dummy_clockevent_device();
234
235 /*
236 * On SMTC we only register VPE0's compare interrupt as clockevent
237 * device.
238 */
239 if (cpu)
240 return 0;
241#endif
242
243 if (!c0_compare_int_usable()) 173 if (!c0_compare_int_usable())
244 return -ENXIO; 174 return -ENXIO;
245 175
@@ -265,13 +195,9 @@ int __cpuinit mips_clockevent_init(void)
265 195
266 cd->rating = 300; 196 cd->rating = 300;
267 cd->irq = irq; 197 cd->irq = irq;
268#ifdef CONFIG_MIPS_MT_SMTC
269 cd->cpumask = CPU_MASK_ALL;
270#else
271 cd->cpumask = cpumask_of_cpu(cpu); 198 cd->cpumask = cpumask_of_cpu(cpu);
272#endif
273 cd->set_next_event = mips_next_event; 199 cd->set_next_event = mips_next_event;
274 cd->set_mode = mips_set_mode; 200 cd->set_mode = mips_set_clock_mode;
275 cd->event_handler = mips_event_handler; 201 cd->event_handler = mips_event_handler;
276 202
277 clockevents_register_device(cd); 203 clockevents_register_device(cd);
@@ -281,12 +207,9 @@ int __cpuinit mips_clockevent_init(void)
281 207
282 cp0_timer_irq_installed = 1; 208 cp0_timer_irq_installed = 1;
283 209
284#ifdef CONFIG_MIPS_MT_SMTC
285#define CPUCTR_IMASKBIT (0x100 << cp0_compare_irq)
286 setup_irq_smtc(irq, &c0_compare_irqaction, CPUCTR_IMASKBIT);
287#else
288 setup_irq(irq, &c0_compare_irqaction); 210 setup_irq(irq, &c0_compare_irqaction);
289#endif
290 211
291 return 0; 212 return 0;
292} 213}
214
215#endif /* Not CONFIG_MIPS_MT_SMTC */