xref: /openbmc/linux/arch/powerpc/platforms/cell/pmu.c (revision b8d312aa)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Cell Broadband Engine Performance Monitor
4  *
5  * (C) Copyright IBM Corporation 2001,2006
6  *
7  * Author:
8  *    David Erb (djerb@us.ibm.com)
9  *    Kevin Corry (kevcorry@us.ibm.com)
10  */
11 
12 #include <linux/interrupt.h>
13 #include <linux/types.h>
14 #include <linux/export.h>
15 #include <asm/io.h>
16 #include <asm/irq_regs.h>
17 #include <asm/machdep.h>
18 #include <asm/pmc.h>
19 #include <asm/reg.h>
20 #include <asm/spu.h>
21 #include <asm/cell-regs.h>
22 
23 #include "interrupt.h"
24 
25 /*
26  * When writing to write-only mmio addresses, save a shadow copy. All of the
27  * registers are 32-bit, but stored in the upper-half of a 64-bit field in
28  * pmd_regs.
29  */
30 
31 #define WRITE_WO_MMIO(reg, x)					\
32 	do {							\
33 		u32 _x = (x);					\
34 		struct cbe_pmd_regs __iomem *pmd_regs;		\
35 		struct cbe_pmd_shadow_regs *shadow_regs;	\
36 		pmd_regs = cbe_get_cpu_pmd_regs(cpu);		\
37 		shadow_regs = cbe_get_cpu_pmd_shadow_regs(cpu);	\
38 		out_be64(&(pmd_regs->reg), (((u64)_x) << 32));	\
39 		shadow_regs->reg = _x;				\
40 	} while (0)
41 
42 #define READ_SHADOW_REG(val, reg)				\
43 	do {							\
44 		struct cbe_pmd_shadow_regs *shadow_regs;	\
45 		shadow_regs = cbe_get_cpu_pmd_shadow_regs(cpu);	\
46 		(val) = shadow_regs->reg;			\
47 	} while (0)
48 
49 #define READ_MMIO_UPPER32(val, reg)				\
50 	do {							\
51 		struct cbe_pmd_regs __iomem *pmd_regs;		\
52 		pmd_regs = cbe_get_cpu_pmd_regs(cpu);		\
53 		(val) = (u32)(in_be64(&pmd_regs->reg) >> 32);	\
54 	} while (0)
55 
56 /*
57  * Physical counter registers.
58  * Each physical counter can act as one 32-bit counter or two 16-bit counters.
59  */
60 
61 u32 cbe_read_phys_ctr(u32 cpu, u32 phys_ctr)
62 {
63 	u32 val_in_latch, val = 0;
64 
65 	if (phys_ctr < NR_PHYS_CTRS) {
66 		READ_SHADOW_REG(val_in_latch, counter_value_in_latch);
67 
68 		/* Read the latch or the actual counter, whichever is newer. */
69 		if (val_in_latch & (1 << phys_ctr)) {
70 			READ_SHADOW_REG(val, pm_ctr[phys_ctr]);
71 		} else {
72 			READ_MMIO_UPPER32(val, pm_ctr[phys_ctr]);
73 		}
74 	}
75 
76 	return val;
77 }
78 EXPORT_SYMBOL_GPL(cbe_read_phys_ctr);
79 
80 void cbe_write_phys_ctr(u32 cpu, u32 phys_ctr, u32 val)
81 {
82 	struct cbe_pmd_shadow_regs *shadow_regs;
83 	u32 pm_ctrl;
84 
85 	if (phys_ctr < NR_PHYS_CTRS) {
86 		/* Writing to a counter only writes to a hardware latch.
87 		 * The new value is not propagated to the actual counter
88 		 * until the performance monitor is enabled.
89 		 */
90 		WRITE_WO_MMIO(pm_ctr[phys_ctr], val);
91 
92 		pm_ctrl = cbe_read_pm(cpu, pm_control);
93 		if (pm_ctrl & CBE_PM_ENABLE_PERF_MON) {
94 			/* The counters are already active, so we need to
95 			 * rewrite the pm_control register to "re-enable"
96 			 * the PMU.
97 			 */
98 			cbe_write_pm(cpu, pm_control, pm_ctrl);
99 		} else {
100 			shadow_regs = cbe_get_cpu_pmd_shadow_regs(cpu);
101 			shadow_regs->counter_value_in_latch |= (1 << phys_ctr);
102 		}
103 	}
104 }
105 EXPORT_SYMBOL_GPL(cbe_write_phys_ctr);
106 
107 /*
108  * "Logical" counter registers.
109  * These will read/write 16-bits or 32-bits depending on the
110  * current size of the counter. Counters 4 - 7 are always 16-bit.
111  */
112 
113 u32 cbe_read_ctr(u32 cpu, u32 ctr)
114 {
115 	u32 val;
116 	u32 phys_ctr = ctr & (NR_PHYS_CTRS - 1);
117 
118 	val = cbe_read_phys_ctr(cpu, phys_ctr);
119 
120 	if (cbe_get_ctr_size(cpu, phys_ctr) == 16)
121 		val = (ctr < NR_PHYS_CTRS) ? (val >> 16) : (val & 0xffff);
122 
123 	return val;
124 }
125 EXPORT_SYMBOL_GPL(cbe_read_ctr);
126 
127 void cbe_write_ctr(u32 cpu, u32 ctr, u32 val)
128 {
129 	u32 phys_ctr;
130 	u32 phys_val;
131 
132 	phys_ctr = ctr & (NR_PHYS_CTRS - 1);
133 
134 	if (cbe_get_ctr_size(cpu, phys_ctr) == 16) {
135 		phys_val = cbe_read_phys_ctr(cpu, phys_ctr);
136 
137 		if (ctr < NR_PHYS_CTRS)
138 			val = (val << 16) | (phys_val & 0xffff);
139 		else
140 			val = (val & 0xffff) | (phys_val & 0xffff0000);
141 	}
142 
143 	cbe_write_phys_ctr(cpu, phys_ctr, val);
144 }
145 EXPORT_SYMBOL_GPL(cbe_write_ctr);
146 
147 /*
148  * Counter-control registers.
149  * Each "logical" counter has a corresponding control register.
150  */
151 
152 u32 cbe_read_pm07_control(u32 cpu, u32 ctr)
153 {
154 	u32 pm07_control = 0;
155 
156 	if (ctr < NR_CTRS)
157 		READ_SHADOW_REG(pm07_control, pm07_control[ctr]);
158 
159 	return pm07_control;
160 }
161 EXPORT_SYMBOL_GPL(cbe_read_pm07_control);
162 
163 void cbe_write_pm07_control(u32 cpu, u32 ctr, u32 val)
164 {
165 	if (ctr < NR_CTRS)
166 		WRITE_WO_MMIO(pm07_control[ctr], val);
167 }
168 EXPORT_SYMBOL_GPL(cbe_write_pm07_control);
169 
170 /*
171  * Other PMU control registers. Most of these are write-only.
172  */
173 
174 u32 cbe_read_pm(u32 cpu, enum pm_reg_name reg)
175 {
176 	u32 val = 0;
177 
178 	switch (reg) {
179 	case group_control:
180 		READ_SHADOW_REG(val, group_control);
181 		break;
182 
183 	case debug_bus_control:
184 		READ_SHADOW_REG(val, debug_bus_control);
185 		break;
186 
187 	case trace_address:
188 		READ_MMIO_UPPER32(val, trace_address);
189 		break;
190 
191 	case ext_tr_timer:
192 		READ_SHADOW_REG(val, ext_tr_timer);
193 		break;
194 
195 	case pm_status:
196 		READ_MMIO_UPPER32(val, pm_status);
197 		break;
198 
199 	case pm_control:
200 		READ_SHADOW_REG(val, pm_control);
201 		break;
202 
203 	case pm_interval:
204 		READ_MMIO_UPPER32(val, pm_interval);
205 		break;
206 
207 	case pm_start_stop:
208 		READ_SHADOW_REG(val, pm_start_stop);
209 		break;
210 	}
211 
212 	return val;
213 }
214 EXPORT_SYMBOL_GPL(cbe_read_pm);
215 
216 void cbe_write_pm(u32 cpu, enum pm_reg_name reg, u32 val)
217 {
218 	switch (reg) {
219 	case group_control:
220 		WRITE_WO_MMIO(group_control, val);
221 		break;
222 
223 	case debug_bus_control:
224 		WRITE_WO_MMIO(debug_bus_control, val);
225 		break;
226 
227 	case trace_address:
228 		WRITE_WO_MMIO(trace_address, val);
229 		break;
230 
231 	case ext_tr_timer:
232 		WRITE_WO_MMIO(ext_tr_timer, val);
233 		break;
234 
235 	case pm_status:
236 		WRITE_WO_MMIO(pm_status, val);
237 		break;
238 
239 	case pm_control:
240 		WRITE_WO_MMIO(pm_control, val);
241 		break;
242 
243 	case pm_interval:
244 		WRITE_WO_MMIO(pm_interval, val);
245 		break;
246 
247 	case pm_start_stop:
248 		WRITE_WO_MMIO(pm_start_stop, val);
249 		break;
250 	}
251 }
252 EXPORT_SYMBOL_GPL(cbe_write_pm);
253 
254 /*
255  * Get/set the size of a physical counter to either 16 or 32 bits.
256  */
257 
258 u32 cbe_get_ctr_size(u32 cpu, u32 phys_ctr)
259 {
260 	u32 pm_ctrl, size = 0;
261 
262 	if (phys_ctr < NR_PHYS_CTRS) {
263 		pm_ctrl = cbe_read_pm(cpu, pm_control);
264 		size = (pm_ctrl & CBE_PM_16BIT_CTR(phys_ctr)) ? 16 : 32;
265 	}
266 
267 	return size;
268 }
269 EXPORT_SYMBOL_GPL(cbe_get_ctr_size);
270 
271 void cbe_set_ctr_size(u32 cpu, u32 phys_ctr, u32 ctr_size)
272 {
273 	u32 pm_ctrl;
274 
275 	if (phys_ctr < NR_PHYS_CTRS) {
276 		pm_ctrl = cbe_read_pm(cpu, pm_control);
277 		switch (ctr_size) {
278 		case 16:
279 			pm_ctrl |= CBE_PM_16BIT_CTR(phys_ctr);
280 			break;
281 
282 		case 32:
283 			pm_ctrl &= ~CBE_PM_16BIT_CTR(phys_ctr);
284 			break;
285 		}
286 		cbe_write_pm(cpu, pm_control, pm_ctrl);
287 	}
288 }
289 EXPORT_SYMBOL_GPL(cbe_set_ctr_size);
290 
291 /*
292  * Enable/disable the entire performance monitoring unit.
293  * When we enable the PMU, all pending writes to counters get committed.
294  */
295 
296 void cbe_enable_pm(u32 cpu)
297 {
298 	struct cbe_pmd_shadow_regs *shadow_regs;
299 	u32 pm_ctrl;
300 
301 	shadow_regs = cbe_get_cpu_pmd_shadow_regs(cpu);
302 	shadow_regs->counter_value_in_latch = 0;
303 
304 	pm_ctrl = cbe_read_pm(cpu, pm_control) | CBE_PM_ENABLE_PERF_MON;
305 	cbe_write_pm(cpu, pm_control, pm_ctrl);
306 }
307 EXPORT_SYMBOL_GPL(cbe_enable_pm);
308 
309 void cbe_disable_pm(u32 cpu)
310 {
311 	u32 pm_ctrl;
312 	pm_ctrl = cbe_read_pm(cpu, pm_control) & ~CBE_PM_ENABLE_PERF_MON;
313 	cbe_write_pm(cpu, pm_control, pm_ctrl);
314 }
315 EXPORT_SYMBOL_GPL(cbe_disable_pm);
316 
317 /*
318  * Reading from the trace_buffer.
319  * The trace buffer is two 64-bit registers. Reading from
320  * the second half automatically increments the trace_address.
321  */
322 
323 void cbe_read_trace_buffer(u32 cpu, u64 *buf)
324 {
325 	struct cbe_pmd_regs __iomem *pmd_regs = cbe_get_cpu_pmd_regs(cpu);
326 
327 	*buf++ = in_be64(&pmd_regs->trace_buffer_0_63);
328 	*buf++ = in_be64(&pmd_regs->trace_buffer_64_127);
329 }
330 EXPORT_SYMBOL_GPL(cbe_read_trace_buffer);
331 
332 /*
333  * Enabling/disabling interrupts for the entire performance monitoring unit.
334  */
335 
336 u32 cbe_get_and_clear_pm_interrupts(u32 cpu)
337 {
338 	/* Reading pm_status clears the interrupt bits. */
339 	return cbe_read_pm(cpu, pm_status);
340 }
341 EXPORT_SYMBOL_GPL(cbe_get_and_clear_pm_interrupts);
342 
343 void cbe_enable_pm_interrupts(u32 cpu, u32 thread, u32 mask)
344 {
345 	/* Set which node and thread will handle the next interrupt. */
346 	iic_set_interrupt_routing(cpu, thread, 0);
347 
348 	/* Enable the interrupt bits in the pm_status register. */
349 	if (mask)
350 		cbe_write_pm(cpu, pm_status, mask);
351 }
352 EXPORT_SYMBOL_GPL(cbe_enable_pm_interrupts);
353 
354 void cbe_disable_pm_interrupts(u32 cpu)
355 {
356 	cbe_get_and_clear_pm_interrupts(cpu);
357 	cbe_write_pm(cpu, pm_status, 0);
358 }
359 EXPORT_SYMBOL_GPL(cbe_disable_pm_interrupts);
360 
361 static irqreturn_t cbe_pm_irq(int irq, void *dev_id)
362 {
363 	perf_irq(get_irq_regs());
364 	return IRQ_HANDLED;
365 }
366 
367 static int __init cbe_init_pm_irq(void)
368 {
369 	unsigned int irq;
370 	int rc, node;
371 
372 	for_each_online_node(node) {
373 		irq = irq_create_mapping(NULL, IIC_IRQ_IOEX_PMI |
374 					       (node << IIC_IRQ_NODE_SHIFT));
375 		if (!irq) {
376 			printk("ERROR: Unable to allocate irq for node %d\n",
377 			       node);
378 			return -EINVAL;
379 		}
380 
381 		rc = request_irq(irq, cbe_pm_irq,
382 				 0, "cbe-pmu-0", NULL);
383 		if (rc) {
384 			printk("ERROR: Request for irq on node %d failed\n",
385 			       node);
386 			return rc;
387 		}
388 	}
389 
390 	return 0;
391 }
392 machine_arch_initcall(cell, cbe_init_pm_irq);
393 
394 void cbe_sync_irq(int node)
395 {
396 	unsigned int irq;
397 
398 	irq = irq_find_mapping(NULL,
399 			       IIC_IRQ_IOEX_PMI
400 			       | (node << IIC_IRQ_NODE_SHIFT));
401 
402 	if (!irq) {
403 		printk(KERN_WARNING "ERROR, unable to get existing irq %d " \
404 		"for node %d\n", irq, node);
405 		return;
406 	}
407 
408 	synchronize_irq(irq);
409 }
410 EXPORT_SYMBOL_GPL(cbe_sync_irq);
411 
412