xref: /openbmc/linux/arch/powerpc/platforms/cell/pmu.c (revision 0ad53fe3)
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/irqdomain.h>
14 #include <linux/types.h>
15 #include <linux/export.h>
16 #include <asm/io.h>
17 #include <asm/irq_regs.h>
18 #include <asm/machdep.h>
19 #include <asm/pmc.h>
20 #include <asm/reg.h>
21 #include <asm/spu.h>
22 #include <asm/cell-regs.h>
23 
24 #include "interrupt.h"
25 
26 /*
27  * When writing to write-only mmio addresses, save a shadow copy. All of the
28  * registers are 32-bit, but stored in the upper-half of a 64-bit field in
29  * pmd_regs.
30  */
31 
32 #define WRITE_WO_MMIO(reg, x)					\
33 	do {							\
34 		u32 _x = (x);					\
35 		struct cbe_pmd_regs __iomem *pmd_regs;		\
36 		struct cbe_pmd_shadow_regs *shadow_regs;	\
37 		pmd_regs = cbe_get_cpu_pmd_regs(cpu);		\
38 		shadow_regs = cbe_get_cpu_pmd_shadow_regs(cpu);	\
39 		out_be64(&(pmd_regs->reg), (((u64)_x) << 32));	\
40 		shadow_regs->reg = _x;				\
41 	} while (0)
42 
43 #define READ_SHADOW_REG(val, reg)				\
44 	do {							\
45 		struct cbe_pmd_shadow_regs *shadow_regs;	\
46 		shadow_regs = cbe_get_cpu_pmd_shadow_regs(cpu);	\
47 		(val) = shadow_regs->reg;			\
48 	} while (0)
49 
50 #define READ_MMIO_UPPER32(val, reg)				\
51 	do {							\
52 		struct cbe_pmd_regs __iomem *pmd_regs;		\
53 		pmd_regs = cbe_get_cpu_pmd_regs(cpu);		\
54 		(val) = (u32)(in_be64(&pmd_regs->reg) >> 32);	\
55 	} while (0)
56 
57 /*
58  * Physical counter registers.
59  * Each physical counter can act as one 32-bit counter or two 16-bit counters.
60  */
61 
62 u32 cbe_read_phys_ctr(u32 cpu, u32 phys_ctr)
63 {
64 	u32 val_in_latch, val = 0;
65 
66 	if (phys_ctr < NR_PHYS_CTRS) {
67 		READ_SHADOW_REG(val_in_latch, counter_value_in_latch);
68 
69 		/* Read the latch or the actual counter, whichever is newer. */
70 		if (val_in_latch & (1 << phys_ctr)) {
71 			READ_SHADOW_REG(val, pm_ctr[phys_ctr]);
72 		} else {
73 			READ_MMIO_UPPER32(val, pm_ctr[phys_ctr]);
74 		}
75 	}
76 
77 	return val;
78 }
79 EXPORT_SYMBOL_GPL(cbe_read_phys_ctr);
80 
81 void cbe_write_phys_ctr(u32 cpu, u32 phys_ctr, u32 val)
82 {
83 	struct cbe_pmd_shadow_regs *shadow_regs;
84 	u32 pm_ctrl;
85 
86 	if (phys_ctr < NR_PHYS_CTRS) {
87 		/* Writing to a counter only writes to a hardware latch.
88 		 * The new value is not propagated to the actual counter
89 		 * until the performance monitor is enabled.
90 		 */
91 		WRITE_WO_MMIO(pm_ctr[phys_ctr], val);
92 
93 		pm_ctrl = cbe_read_pm(cpu, pm_control);
94 		if (pm_ctrl & CBE_PM_ENABLE_PERF_MON) {
95 			/* The counters are already active, so we need to
96 			 * rewrite the pm_control register to "re-enable"
97 			 * the PMU.
98 			 */
99 			cbe_write_pm(cpu, pm_control, pm_ctrl);
100 		} else {
101 			shadow_regs = cbe_get_cpu_pmd_shadow_regs(cpu);
102 			shadow_regs->counter_value_in_latch |= (1 << phys_ctr);
103 		}
104 	}
105 }
106 EXPORT_SYMBOL_GPL(cbe_write_phys_ctr);
107 
108 /*
109  * "Logical" counter registers.
110  * These will read/write 16-bits or 32-bits depending on the
111  * current size of the counter. Counters 4 - 7 are always 16-bit.
112  */
113 
114 u32 cbe_read_ctr(u32 cpu, u32 ctr)
115 {
116 	u32 val;
117 	u32 phys_ctr = ctr & (NR_PHYS_CTRS - 1);
118 
119 	val = cbe_read_phys_ctr(cpu, phys_ctr);
120 
121 	if (cbe_get_ctr_size(cpu, phys_ctr) == 16)
122 		val = (ctr < NR_PHYS_CTRS) ? (val >> 16) : (val & 0xffff);
123 
124 	return val;
125 }
126 EXPORT_SYMBOL_GPL(cbe_read_ctr);
127 
128 void cbe_write_ctr(u32 cpu, u32 ctr, u32 val)
129 {
130 	u32 phys_ctr;
131 	u32 phys_val;
132 
133 	phys_ctr = ctr & (NR_PHYS_CTRS - 1);
134 
135 	if (cbe_get_ctr_size(cpu, phys_ctr) == 16) {
136 		phys_val = cbe_read_phys_ctr(cpu, phys_ctr);
137 
138 		if (ctr < NR_PHYS_CTRS)
139 			val = (val << 16) | (phys_val & 0xffff);
140 		else
141 			val = (val & 0xffff) | (phys_val & 0xffff0000);
142 	}
143 
144 	cbe_write_phys_ctr(cpu, phys_ctr, val);
145 }
146 EXPORT_SYMBOL_GPL(cbe_write_ctr);
147 
148 /*
149  * Counter-control registers.
150  * Each "logical" counter has a corresponding control register.
151  */
152 
153 u32 cbe_read_pm07_control(u32 cpu, u32 ctr)
154 {
155 	u32 pm07_control = 0;
156 
157 	if (ctr < NR_CTRS)
158 		READ_SHADOW_REG(pm07_control, pm07_control[ctr]);
159 
160 	return pm07_control;
161 }
162 EXPORT_SYMBOL_GPL(cbe_read_pm07_control);
163 
164 void cbe_write_pm07_control(u32 cpu, u32 ctr, u32 val)
165 {
166 	if (ctr < NR_CTRS)
167 		WRITE_WO_MMIO(pm07_control[ctr], val);
168 }
169 EXPORT_SYMBOL_GPL(cbe_write_pm07_control);
170 
171 /*
172  * Other PMU control registers. Most of these are write-only.
173  */
174 
175 u32 cbe_read_pm(u32 cpu, enum pm_reg_name reg)
176 {
177 	u32 val = 0;
178 
179 	switch (reg) {
180 	case group_control:
181 		READ_SHADOW_REG(val, group_control);
182 		break;
183 
184 	case debug_bus_control:
185 		READ_SHADOW_REG(val, debug_bus_control);
186 		break;
187 
188 	case trace_address:
189 		READ_MMIO_UPPER32(val, trace_address);
190 		break;
191 
192 	case ext_tr_timer:
193 		READ_SHADOW_REG(val, ext_tr_timer);
194 		break;
195 
196 	case pm_status:
197 		READ_MMIO_UPPER32(val, pm_status);
198 		break;
199 
200 	case pm_control:
201 		READ_SHADOW_REG(val, pm_control);
202 		break;
203 
204 	case pm_interval:
205 		READ_MMIO_UPPER32(val, pm_interval);
206 		break;
207 
208 	case pm_start_stop:
209 		READ_SHADOW_REG(val, pm_start_stop);
210 		break;
211 	}
212 
213 	return val;
214 }
215 EXPORT_SYMBOL_GPL(cbe_read_pm);
216 
217 void cbe_write_pm(u32 cpu, enum pm_reg_name reg, u32 val)
218 {
219 	switch (reg) {
220 	case group_control:
221 		WRITE_WO_MMIO(group_control, val);
222 		break;
223 
224 	case debug_bus_control:
225 		WRITE_WO_MMIO(debug_bus_control, val);
226 		break;
227 
228 	case trace_address:
229 		WRITE_WO_MMIO(trace_address, val);
230 		break;
231 
232 	case ext_tr_timer:
233 		WRITE_WO_MMIO(ext_tr_timer, val);
234 		break;
235 
236 	case pm_status:
237 		WRITE_WO_MMIO(pm_status, val);
238 		break;
239 
240 	case pm_control:
241 		WRITE_WO_MMIO(pm_control, val);
242 		break;
243 
244 	case pm_interval:
245 		WRITE_WO_MMIO(pm_interval, val);
246 		break;
247 
248 	case pm_start_stop:
249 		WRITE_WO_MMIO(pm_start_stop, val);
250 		break;
251 	}
252 }
253 EXPORT_SYMBOL_GPL(cbe_write_pm);
254 
255 /*
256  * Get/set the size of a physical counter to either 16 or 32 bits.
257  */
258 
259 u32 cbe_get_ctr_size(u32 cpu, u32 phys_ctr)
260 {
261 	u32 pm_ctrl, size = 0;
262 
263 	if (phys_ctr < NR_PHYS_CTRS) {
264 		pm_ctrl = cbe_read_pm(cpu, pm_control);
265 		size = (pm_ctrl & CBE_PM_16BIT_CTR(phys_ctr)) ? 16 : 32;
266 	}
267 
268 	return size;
269 }
270 EXPORT_SYMBOL_GPL(cbe_get_ctr_size);
271 
272 void cbe_set_ctr_size(u32 cpu, u32 phys_ctr, u32 ctr_size)
273 {
274 	u32 pm_ctrl;
275 
276 	if (phys_ctr < NR_PHYS_CTRS) {
277 		pm_ctrl = cbe_read_pm(cpu, pm_control);
278 		switch (ctr_size) {
279 		case 16:
280 			pm_ctrl |= CBE_PM_16BIT_CTR(phys_ctr);
281 			break;
282 
283 		case 32:
284 			pm_ctrl &= ~CBE_PM_16BIT_CTR(phys_ctr);
285 			break;
286 		}
287 		cbe_write_pm(cpu, pm_control, pm_ctrl);
288 	}
289 }
290 EXPORT_SYMBOL_GPL(cbe_set_ctr_size);
291 
292 /*
293  * Enable/disable the entire performance monitoring unit.
294  * When we enable the PMU, all pending writes to counters get committed.
295  */
296 
297 void cbe_enable_pm(u32 cpu)
298 {
299 	struct cbe_pmd_shadow_regs *shadow_regs;
300 	u32 pm_ctrl;
301 
302 	shadow_regs = cbe_get_cpu_pmd_shadow_regs(cpu);
303 	shadow_regs->counter_value_in_latch = 0;
304 
305 	pm_ctrl = cbe_read_pm(cpu, pm_control) | CBE_PM_ENABLE_PERF_MON;
306 	cbe_write_pm(cpu, pm_control, pm_ctrl);
307 }
308 EXPORT_SYMBOL_GPL(cbe_enable_pm);
309 
310 void cbe_disable_pm(u32 cpu)
311 {
312 	u32 pm_ctrl;
313 	pm_ctrl = cbe_read_pm(cpu, pm_control) & ~CBE_PM_ENABLE_PERF_MON;
314 	cbe_write_pm(cpu, pm_control, pm_ctrl);
315 }
316 EXPORT_SYMBOL_GPL(cbe_disable_pm);
317 
318 /*
319  * Reading from the trace_buffer.
320  * The trace buffer is two 64-bit registers. Reading from
321  * the second half automatically increments the trace_address.
322  */
323 
324 void cbe_read_trace_buffer(u32 cpu, u64 *buf)
325 {
326 	struct cbe_pmd_regs __iomem *pmd_regs = cbe_get_cpu_pmd_regs(cpu);
327 
328 	*buf++ = in_be64(&pmd_regs->trace_buffer_0_63);
329 	*buf++ = in_be64(&pmd_regs->trace_buffer_64_127);
330 }
331 EXPORT_SYMBOL_GPL(cbe_read_trace_buffer);
332 
333 /*
334  * Enabling/disabling interrupts for the entire performance monitoring unit.
335  */
336 
337 u32 cbe_get_and_clear_pm_interrupts(u32 cpu)
338 {
339 	/* Reading pm_status clears the interrupt bits. */
340 	return cbe_read_pm(cpu, pm_status);
341 }
342 EXPORT_SYMBOL_GPL(cbe_get_and_clear_pm_interrupts);
343 
344 void cbe_enable_pm_interrupts(u32 cpu, u32 thread, u32 mask)
345 {
346 	/* Set which node and thread will handle the next interrupt. */
347 	iic_set_interrupt_routing(cpu, thread, 0);
348 
349 	/* Enable the interrupt bits in the pm_status register. */
350 	if (mask)
351 		cbe_write_pm(cpu, pm_status, mask);
352 }
353 EXPORT_SYMBOL_GPL(cbe_enable_pm_interrupts);
354 
355 void cbe_disable_pm_interrupts(u32 cpu)
356 {
357 	cbe_get_and_clear_pm_interrupts(cpu);
358 	cbe_write_pm(cpu, pm_status, 0);
359 }
360 EXPORT_SYMBOL_GPL(cbe_disable_pm_interrupts);
361 
362 static irqreturn_t cbe_pm_irq(int irq, void *dev_id)
363 {
364 	perf_irq(get_irq_regs());
365 	return IRQ_HANDLED;
366 }
367 
368 static int __init cbe_init_pm_irq(void)
369 {
370 	unsigned int irq;
371 	int rc, node;
372 
373 	for_each_online_node(node) {
374 		irq = irq_create_mapping(NULL, IIC_IRQ_IOEX_PMI |
375 					       (node << IIC_IRQ_NODE_SHIFT));
376 		if (!irq) {
377 			printk("ERROR: Unable to allocate irq for node %d\n",
378 			       node);
379 			return -EINVAL;
380 		}
381 
382 		rc = request_irq(irq, cbe_pm_irq,
383 				 0, "cbe-pmu-0", NULL);
384 		if (rc) {
385 			printk("ERROR: Request for irq on node %d failed\n",
386 			       node);
387 			return rc;
388 		}
389 	}
390 
391 	return 0;
392 }
393 machine_arch_initcall(cell, cbe_init_pm_irq);
394 
395 void cbe_sync_irq(int node)
396 {
397 	unsigned int irq;
398 
399 	irq = irq_find_mapping(NULL,
400 			       IIC_IRQ_IOEX_PMI
401 			       | (node << IIC_IRQ_NODE_SHIFT));
402 
403 	if (!irq) {
404 		printk(KERN_WARNING "ERROR, unable to get existing irq %d " \
405 		"for node %d\n", irq, node);
406 		return;
407 	}
408 
409 	synchronize_irq(irq);
410 }
411 EXPORT_SYMBOL_GPL(cbe_sync_irq);
412 
413