1 /*
2  * arch/powerpc/oprofile/op_model_7450.c
3  *
4  * Freescale 745x/744x oprofile support, based on fsl_booke support
5  * Copyright (C) 2004 Anton Blanchard <anton@au.ibm.com>, IBM
6  *
7  * Copyright (c) 2004 Freescale Semiconductor, Inc
8  *
9  * Author: Andy Fleming
10  * Maintainer: Kumar Gala <galak@kernel.crashing.org>
11  *
12  * This program is free software; you can redistribute it and/or
13  * modify it under the terms of the GNU General Public License
14  * as published by the Free Software Foundation; either version
15  * 2 of the License, or (at your option) any later version.
16  */
17 
18 #include <linux/oprofile.h>
19 #include <linux/init.h>
20 #include <linux/smp.h>
21 #include <asm/ptrace.h>
22 #include <asm/processor.h>
23 #include <asm/cputable.h>
24 #include <asm/page.h>
25 #include <asm/pmc.h>
26 #include <asm/oprofile_impl.h>
27 
28 static unsigned long reset_value[OP_MAX_COUNTER];
29 
30 static int oprofile_running;
31 static u32 mmcr0_val, mmcr1_val, mmcr2_val, num_pmcs;
32 
33 #define MMCR0_PMC1_SHIFT	6
34 #define MMCR0_PMC2_SHIFT	0
35 #define MMCR1_PMC3_SHIFT	27
36 #define MMCR1_PMC4_SHIFT	22
37 #define MMCR1_PMC5_SHIFT	17
38 #define MMCR1_PMC6_SHIFT	11
39 
40 #define mmcr0_event1(event) \
41 	((event << MMCR0_PMC1_SHIFT) & MMCR0_PMC1SEL)
42 #define mmcr0_event2(event) \
43 	((event << MMCR0_PMC2_SHIFT) & MMCR0_PMC2SEL)
44 
45 #define mmcr1_event3(event) \
46 	((event << MMCR1_PMC3_SHIFT) & MMCR1_PMC3SEL)
47 #define mmcr1_event4(event) \
48 	((event << MMCR1_PMC4_SHIFT) & MMCR1_PMC4SEL)
49 #define mmcr1_event5(event) \
50 	((event << MMCR1_PMC5_SHIFT) & MMCR1_PMC5SEL)
51 #define mmcr1_event6(event) \
52 	((event << MMCR1_PMC6_SHIFT) & MMCR1_PMC6SEL)
53 
54 #define MMCR0_INIT (MMCR0_FC | MMCR0_FCS | MMCR0_FCP | MMCR0_FCM1 | MMCR0_FCM0)
55 
56 /* Unfreezes the counters on this CPU, enables the interrupt,
57  * enables the counters to trigger the interrupt, and sets the
58  * counters to only count when the mark bit is not set.
59  */
pmc_start_ctrs(void)60 static void pmc_start_ctrs(void)
61 {
62 	u32 mmcr0 = mfspr(SPRN_MMCR0);
63 
64 	mmcr0 &= ~(MMCR0_FC | MMCR0_FCM0);
65 	mmcr0 |= (MMCR0_FCECE | MMCR0_PMC1CE | MMCR0_PMCnCE | MMCR0_PMXE);
66 
67 	mtspr(SPRN_MMCR0, mmcr0);
68 }
69 
70 /* Disables the counters on this CPU, and freezes them */
pmc_stop_ctrs(void)71 static void pmc_stop_ctrs(void)
72 {
73 	u32 mmcr0 = mfspr(SPRN_MMCR0);
74 
75 	mmcr0 |= MMCR0_FC;
76 	mmcr0 &= ~(MMCR0_FCECE | MMCR0_PMC1CE | MMCR0_PMCnCE | MMCR0_PMXE);
77 
78 	mtspr(SPRN_MMCR0, mmcr0);
79 }
80 
81 /* Configures the counters on this CPU based on the global
82  * settings */
fsl7450_cpu_setup(struct op_counter_config * ctr)83 static int fsl7450_cpu_setup(struct op_counter_config *ctr)
84 {
85 	/* freeze all counters */
86 	pmc_stop_ctrs();
87 
88 	mtspr(SPRN_MMCR0, mmcr0_val);
89 	mtspr(SPRN_MMCR1, mmcr1_val);
90 	if (num_pmcs > 4)
91 		mtspr(SPRN_MMCR2, mmcr2_val);
92 
93 	return 0;
94 }
95 
96 /* Configures the global settings for the countes on all CPUs. */
fsl7450_reg_setup(struct op_counter_config * ctr,struct op_system_config * sys,int num_ctrs)97 static int fsl7450_reg_setup(struct op_counter_config *ctr,
98 			     struct op_system_config *sys,
99 			     int num_ctrs)
100 {
101 	int i;
102 
103 	num_pmcs = num_ctrs;
104 	/* Our counters count up, and "count" refers to
105 	 * how much before the next interrupt, and we interrupt
106 	 * on overflow.  So we calculate the starting value
107 	 * which will give us "count" until overflow.
108 	 * Then we set the events on the enabled counters */
109 	for (i = 0; i < num_ctrs; ++i)
110 		reset_value[i] = 0x80000000UL - ctr[i].count;
111 
112 	/* Set events for Counters 1 & 2 */
113 	mmcr0_val = MMCR0_INIT | mmcr0_event1(ctr[0].event)
114 		| mmcr0_event2(ctr[1].event);
115 
116 	/* Setup user/kernel bits */
117 	if (sys->enable_kernel)
118 		mmcr0_val &= ~(MMCR0_FCS);
119 
120 	if (sys->enable_user)
121 		mmcr0_val &= ~(MMCR0_FCP);
122 
123 	/* Set events for Counters 3-6 */
124 	mmcr1_val = mmcr1_event3(ctr[2].event)
125 		| mmcr1_event4(ctr[3].event);
126 	if (num_ctrs > 4)
127 		mmcr1_val |= mmcr1_event5(ctr[4].event)
128 			| mmcr1_event6(ctr[5].event);
129 
130 	mmcr2_val = 0;
131 
132 	return 0;
133 }
134 
135 /* Sets the counters on this CPU to the chosen values, and starts them */
fsl7450_start(struct op_counter_config * ctr)136 static int fsl7450_start(struct op_counter_config *ctr)
137 {
138 	int i;
139 
140 	mtmsr(mfmsr() | MSR_PMM);
141 
142 	for (i = 0; i < num_pmcs; ++i) {
143 		if (ctr[i].enabled)
144 			classic_ctr_write(i, reset_value[i]);
145 		else
146 			classic_ctr_write(i, 0);
147 	}
148 
149 	/* Clear the freeze bit, and enable the interrupt.
150 	 * The counters won't actually start until the rfi clears
151 	 * the PMM bit */
152 	pmc_start_ctrs();
153 
154 	oprofile_running = 1;
155 
156 	return 0;
157 }
158 
159 /* Stop the counters on this CPU */
fsl7450_stop(void)160 static void fsl7450_stop(void)
161 {
162 	/* freeze counters */
163 	pmc_stop_ctrs();
164 
165 	oprofile_running = 0;
166 
167 	mb();
168 }
169 
170 
171 /* Handle the interrupt on this CPU, and log a sample for each
172  * event that triggered the interrupt */
fsl7450_handle_interrupt(struct pt_regs * regs,struct op_counter_config * ctr)173 static void fsl7450_handle_interrupt(struct pt_regs *regs,
174 				    struct op_counter_config *ctr)
175 {
176 	unsigned long pc;
177 	int is_kernel;
178 	int val;
179 	int i;
180 
181 	/* set the PMM bit (see comment below) */
182 	mtmsr(mfmsr() | MSR_PMM);
183 
184 	pc = mfspr(SPRN_SIAR);
185 	is_kernel = is_kernel_addr(pc);
186 
187 	for (i = 0; i < num_pmcs; ++i) {
188 		val = classic_ctr_read(i);
189 		if (val < 0) {
190 			if (oprofile_running && ctr[i].enabled) {
191 				oprofile_add_ext_sample(pc, regs, i, is_kernel);
192 				classic_ctr_write(i, reset_value[i]);
193 			} else {
194 				classic_ctr_write(i, 0);
195 			}
196 		}
197 	}
198 
199 	/* The freeze bit was set by the interrupt. */
200 	/* Clear the freeze bit, and reenable the interrupt.
201 	 * The counters won't actually start until the rfi clears
202 	 * the PM/M bit */
203 	pmc_start_ctrs();
204 }
205 
206 struct op_powerpc_model op_model_7450= {
207 	.reg_setup		= fsl7450_reg_setup,
208 	.cpu_setup		= fsl7450_cpu_setup,
209 	.start			= fsl7450_start,
210 	.stop			= fsl7450_stop,
211 	.handle_interrupt	= fsl7450_handle_interrupt,
212 };
213