xref: /openbmc/linux/arch/powerpc/platforms/cell/pmu.c (revision 63dc02bd)
1 /*
2  * Cell Broadband Engine Performance Monitor
3  *
4  * (C) Copyright IBM Corporation 2001,2006
5  *
6  * Author:
7  *    David Erb (djerb@us.ibm.com)
8  *    Kevin Corry (kevcorry@us.ibm.com)
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2, or (at your option)
13  * any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23  */
24 
25 #include <linux/interrupt.h>
26 #include <linux/types.h>
27 #include <linux/export.h>
28 #include <asm/io.h>
29 #include <asm/irq_regs.h>
30 #include <asm/machdep.h>
31 #include <asm/pmc.h>
32 #include <asm/reg.h>
33 #include <asm/spu.h>
34 #include <asm/cell-regs.h>
35 
36 #include "interrupt.h"
37 
38 /*
39  * When writing to write-only mmio addresses, save a shadow copy. All of the
40  * registers are 32-bit, but stored in the upper-half of a 64-bit field in
41  * pmd_regs.
42  */
43 
44 #define WRITE_WO_MMIO(reg, x)					\
45 	do {							\
46 		u32 _x = (x);					\
47 		struct cbe_pmd_regs __iomem *pmd_regs;		\
48 		struct cbe_pmd_shadow_regs *shadow_regs;	\
49 		pmd_regs = cbe_get_cpu_pmd_regs(cpu);		\
50 		shadow_regs = cbe_get_cpu_pmd_shadow_regs(cpu);	\
51 		out_be64(&(pmd_regs->reg), (((u64)_x) << 32));	\
52 		shadow_regs->reg = _x;				\
53 	} while (0)
54 
55 #define READ_SHADOW_REG(val, reg)				\
56 	do {							\
57 		struct cbe_pmd_shadow_regs *shadow_regs;	\
58 		shadow_regs = cbe_get_cpu_pmd_shadow_regs(cpu);	\
59 		(val) = shadow_regs->reg;			\
60 	} while (0)
61 
62 #define READ_MMIO_UPPER32(val, reg)				\
63 	do {							\
64 		struct cbe_pmd_regs __iomem *pmd_regs;		\
65 		pmd_regs = cbe_get_cpu_pmd_regs(cpu);		\
66 		(val) = (u32)(in_be64(&pmd_regs->reg) >> 32);	\
67 	} while (0)
68 
69 /*
70  * Physical counter registers.
71  * Each physical counter can act as one 32-bit counter or two 16-bit counters.
72  */
73 
74 u32 cbe_read_phys_ctr(u32 cpu, u32 phys_ctr)
75 {
76 	u32 val_in_latch, val = 0;
77 
78 	if (phys_ctr < NR_PHYS_CTRS) {
79 		READ_SHADOW_REG(val_in_latch, counter_value_in_latch);
80 
81 		/* Read the latch or the actual counter, whichever is newer. */
82 		if (val_in_latch & (1 << phys_ctr)) {
83 			READ_SHADOW_REG(val, pm_ctr[phys_ctr]);
84 		} else {
85 			READ_MMIO_UPPER32(val, pm_ctr[phys_ctr]);
86 		}
87 	}
88 
89 	return val;
90 }
91 EXPORT_SYMBOL_GPL(cbe_read_phys_ctr);
92 
93 void cbe_write_phys_ctr(u32 cpu, u32 phys_ctr, u32 val)
94 {
95 	struct cbe_pmd_shadow_regs *shadow_regs;
96 	u32 pm_ctrl;
97 
98 	if (phys_ctr < NR_PHYS_CTRS) {
99 		/* Writing to a counter only writes to a hardware latch.
100 		 * The new value is not propagated to the actual counter
101 		 * until the performance monitor is enabled.
102 		 */
103 		WRITE_WO_MMIO(pm_ctr[phys_ctr], val);
104 
105 		pm_ctrl = cbe_read_pm(cpu, pm_control);
106 		if (pm_ctrl & CBE_PM_ENABLE_PERF_MON) {
107 			/* The counters are already active, so we need to
108 			 * rewrite the pm_control register to "re-enable"
109 			 * the PMU.
110 			 */
111 			cbe_write_pm(cpu, pm_control, pm_ctrl);
112 		} else {
113 			shadow_regs = cbe_get_cpu_pmd_shadow_regs(cpu);
114 			shadow_regs->counter_value_in_latch |= (1 << phys_ctr);
115 		}
116 	}
117 }
118 EXPORT_SYMBOL_GPL(cbe_write_phys_ctr);
119 
120 /*
121  * "Logical" counter registers.
122  * These will read/write 16-bits or 32-bits depending on the
123  * current size of the counter. Counters 4 - 7 are always 16-bit.
124  */
125 
126 u32 cbe_read_ctr(u32 cpu, u32 ctr)
127 {
128 	u32 val;
129 	u32 phys_ctr = ctr & (NR_PHYS_CTRS - 1);
130 
131 	val = cbe_read_phys_ctr(cpu, phys_ctr);
132 
133 	if (cbe_get_ctr_size(cpu, phys_ctr) == 16)
134 		val = (ctr < NR_PHYS_CTRS) ? (val >> 16) : (val & 0xffff);
135 
136 	return val;
137 }
138 EXPORT_SYMBOL_GPL(cbe_read_ctr);
139 
140 void cbe_write_ctr(u32 cpu, u32 ctr, u32 val)
141 {
142 	u32 phys_ctr;
143 	u32 phys_val;
144 
145 	phys_ctr = ctr & (NR_PHYS_CTRS - 1);
146 
147 	if (cbe_get_ctr_size(cpu, phys_ctr) == 16) {
148 		phys_val = cbe_read_phys_ctr(cpu, phys_ctr);
149 
150 		if (ctr < NR_PHYS_CTRS)
151 			val = (val << 16) | (phys_val & 0xffff);
152 		else
153 			val = (val & 0xffff) | (phys_val & 0xffff0000);
154 	}
155 
156 	cbe_write_phys_ctr(cpu, phys_ctr, val);
157 }
158 EXPORT_SYMBOL_GPL(cbe_write_ctr);
159 
160 /*
161  * Counter-control registers.
162  * Each "logical" counter has a corresponding control register.
163  */
164 
165 u32 cbe_read_pm07_control(u32 cpu, u32 ctr)
166 {
167 	u32 pm07_control = 0;
168 
169 	if (ctr < NR_CTRS)
170 		READ_SHADOW_REG(pm07_control, pm07_control[ctr]);
171 
172 	return pm07_control;
173 }
174 EXPORT_SYMBOL_GPL(cbe_read_pm07_control);
175 
176 void cbe_write_pm07_control(u32 cpu, u32 ctr, u32 val)
177 {
178 	if (ctr < NR_CTRS)
179 		WRITE_WO_MMIO(pm07_control[ctr], val);
180 }
181 EXPORT_SYMBOL_GPL(cbe_write_pm07_control);
182 
183 /*
184  * Other PMU control registers. Most of these are write-only.
185  */
186 
187 u32 cbe_read_pm(u32 cpu, enum pm_reg_name reg)
188 {
189 	u32 val = 0;
190 
191 	switch (reg) {
192 	case group_control:
193 		READ_SHADOW_REG(val, group_control);
194 		break;
195 
196 	case debug_bus_control:
197 		READ_SHADOW_REG(val, debug_bus_control);
198 		break;
199 
200 	case trace_address:
201 		READ_MMIO_UPPER32(val, trace_address);
202 		break;
203 
204 	case ext_tr_timer:
205 		READ_SHADOW_REG(val, ext_tr_timer);
206 		break;
207 
208 	case pm_status:
209 		READ_MMIO_UPPER32(val, pm_status);
210 		break;
211 
212 	case pm_control:
213 		READ_SHADOW_REG(val, pm_control);
214 		break;
215 
216 	case pm_interval:
217 		READ_MMIO_UPPER32(val, pm_interval);
218 		break;
219 
220 	case pm_start_stop:
221 		READ_SHADOW_REG(val, pm_start_stop);
222 		break;
223 	}
224 
225 	return val;
226 }
227 EXPORT_SYMBOL_GPL(cbe_read_pm);
228 
229 void cbe_write_pm(u32 cpu, enum pm_reg_name reg, u32 val)
230 {
231 	switch (reg) {
232 	case group_control:
233 		WRITE_WO_MMIO(group_control, val);
234 		break;
235 
236 	case debug_bus_control:
237 		WRITE_WO_MMIO(debug_bus_control, val);
238 		break;
239 
240 	case trace_address:
241 		WRITE_WO_MMIO(trace_address, val);
242 		break;
243 
244 	case ext_tr_timer:
245 		WRITE_WO_MMIO(ext_tr_timer, val);
246 		break;
247 
248 	case pm_status:
249 		WRITE_WO_MMIO(pm_status, val);
250 		break;
251 
252 	case pm_control:
253 		WRITE_WO_MMIO(pm_control, val);
254 		break;
255 
256 	case pm_interval:
257 		WRITE_WO_MMIO(pm_interval, val);
258 		break;
259 
260 	case pm_start_stop:
261 		WRITE_WO_MMIO(pm_start_stop, val);
262 		break;
263 	}
264 }
265 EXPORT_SYMBOL_GPL(cbe_write_pm);
266 
267 /*
268  * Get/set the size of a physical counter to either 16 or 32 bits.
269  */
270 
271 u32 cbe_get_ctr_size(u32 cpu, u32 phys_ctr)
272 {
273 	u32 pm_ctrl, size = 0;
274 
275 	if (phys_ctr < NR_PHYS_CTRS) {
276 		pm_ctrl = cbe_read_pm(cpu, pm_control);
277 		size = (pm_ctrl & CBE_PM_16BIT_CTR(phys_ctr)) ? 16 : 32;
278 	}
279 
280 	return size;
281 }
282 EXPORT_SYMBOL_GPL(cbe_get_ctr_size);
283 
284 void cbe_set_ctr_size(u32 cpu, u32 phys_ctr, u32 ctr_size)
285 {
286 	u32 pm_ctrl;
287 
288 	if (phys_ctr < NR_PHYS_CTRS) {
289 		pm_ctrl = cbe_read_pm(cpu, pm_control);
290 		switch (ctr_size) {
291 		case 16:
292 			pm_ctrl |= CBE_PM_16BIT_CTR(phys_ctr);
293 			break;
294 
295 		case 32:
296 			pm_ctrl &= ~CBE_PM_16BIT_CTR(phys_ctr);
297 			break;
298 		}
299 		cbe_write_pm(cpu, pm_control, pm_ctrl);
300 	}
301 }
302 EXPORT_SYMBOL_GPL(cbe_set_ctr_size);
303 
304 /*
305  * Enable/disable the entire performance monitoring unit.
306  * When we enable the PMU, all pending writes to counters get committed.
307  */
308 
309 void cbe_enable_pm(u32 cpu)
310 {
311 	struct cbe_pmd_shadow_regs *shadow_regs;
312 	u32 pm_ctrl;
313 
314 	shadow_regs = cbe_get_cpu_pmd_shadow_regs(cpu);
315 	shadow_regs->counter_value_in_latch = 0;
316 
317 	pm_ctrl = cbe_read_pm(cpu, pm_control) | CBE_PM_ENABLE_PERF_MON;
318 	cbe_write_pm(cpu, pm_control, pm_ctrl);
319 }
320 EXPORT_SYMBOL_GPL(cbe_enable_pm);
321 
322 void cbe_disable_pm(u32 cpu)
323 {
324 	u32 pm_ctrl;
325 	pm_ctrl = cbe_read_pm(cpu, pm_control) & ~CBE_PM_ENABLE_PERF_MON;
326 	cbe_write_pm(cpu, pm_control, pm_ctrl);
327 }
328 EXPORT_SYMBOL_GPL(cbe_disable_pm);
329 
330 /*
331  * Reading from the trace_buffer.
332  * The trace buffer is two 64-bit registers. Reading from
333  * the second half automatically increments the trace_address.
334  */
335 
336 void cbe_read_trace_buffer(u32 cpu, u64 *buf)
337 {
338 	struct cbe_pmd_regs __iomem *pmd_regs = cbe_get_cpu_pmd_regs(cpu);
339 
340 	*buf++ = in_be64(&pmd_regs->trace_buffer_0_63);
341 	*buf++ = in_be64(&pmd_regs->trace_buffer_64_127);
342 }
343 EXPORT_SYMBOL_GPL(cbe_read_trace_buffer);
344 
345 /*
346  * Enabling/disabling interrupts for the entire performance monitoring unit.
347  */
348 
349 u32 cbe_get_and_clear_pm_interrupts(u32 cpu)
350 {
351 	/* Reading pm_status clears the interrupt bits. */
352 	return cbe_read_pm(cpu, pm_status);
353 }
354 EXPORT_SYMBOL_GPL(cbe_get_and_clear_pm_interrupts);
355 
356 void cbe_enable_pm_interrupts(u32 cpu, u32 thread, u32 mask)
357 {
358 	/* Set which node and thread will handle the next interrupt. */
359 	iic_set_interrupt_routing(cpu, thread, 0);
360 
361 	/* Enable the interrupt bits in the pm_status register. */
362 	if (mask)
363 		cbe_write_pm(cpu, pm_status, mask);
364 }
365 EXPORT_SYMBOL_GPL(cbe_enable_pm_interrupts);
366 
367 void cbe_disable_pm_interrupts(u32 cpu)
368 {
369 	cbe_get_and_clear_pm_interrupts(cpu);
370 	cbe_write_pm(cpu, pm_status, 0);
371 }
372 EXPORT_SYMBOL_GPL(cbe_disable_pm_interrupts);
373 
374 static irqreturn_t cbe_pm_irq(int irq, void *dev_id)
375 {
376 	perf_irq(get_irq_regs());
377 	return IRQ_HANDLED;
378 }
379 
380 static int __init cbe_init_pm_irq(void)
381 {
382 	unsigned int irq;
383 	int rc, node;
384 
385 	for_each_node(node) {
386 		irq = irq_create_mapping(NULL, IIC_IRQ_IOEX_PMI |
387 					       (node << IIC_IRQ_NODE_SHIFT));
388 		if (irq == NO_IRQ) {
389 			printk("ERROR: Unable to allocate irq for node %d\n",
390 			       node);
391 			return -EINVAL;
392 		}
393 
394 		rc = request_irq(irq, cbe_pm_irq,
395 				 0, "cbe-pmu-0", NULL);
396 		if (rc) {
397 			printk("ERROR: Request for irq on node %d failed\n",
398 			       node);
399 			return rc;
400 		}
401 	}
402 
403 	return 0;
404 }
405 machine_arch_initcall(cell, cbe_init_pm_irq);
406 
407 void cbe_sync_irq(int node)
408 {
409 	unsigned int irq;
410 
411 	irq = irq_find_mapping(NULL,
412 			       IIC_IRQ_IOEX_PMI
413 			       | (node << IIC_IRQ_NODE_SHIFT));
414 
415 	if (irq == NO_IRQ) {
416 		printk(KERN_WARNING "ERROR, unable to get existing irq %d " \
417 		"for node %d\n", irq, node);
418 		return;
419 	}
420 
421 	synchronize_irq(irq);
422 }
423 EXPORT_SYMBOL_GPL(cbe_sync_irq);
424 
425