1/*
  2 * This file is subject to the terms and conditions of the GNU General Public
  3 * License.  See the file "COPYING" in the main directory of this archive
  4 * for more details.
  5 *
  6 */
  7#include <linux/init.h>
  8#include <linux/cpu.h>
  9#include <linux/smp.h>
 10#include <linux/proc_fs.h>
 11#include <linux/oprofile.h>
 12#include <linux/spinlock.h>
 13#include <linux/interrupt.h>
 14#include <linux/uaccess.h>
 15#include <irq.h>
 16#include <loongson.h>
 17#include "op_impl.h"
 18
 19#define LOONGSON3_PERFCNT_OVERFLOW	(1ULL << 63)
 20
 21#define LOONGSON3_PERFCTRL_EXL		(1UL << 0)
 22#define LOONGSON3_PERFCTRL_KERNEL	(1UL << 1)
 23#define LOONGSON3_PERFCTRL_SUPERVISOR	(1UL << 2)
 24#define LOONGSON3_PERFCTRL_USER		(1UL << 3)
 25#define LOONGSON3_PERFCTRL_ENABLE	(1UL << 4)
 26#define LOONGSON3_PERFCTRL_W		(1UL << 30)
 27#define LOONGSON3_PERFCTRL_M		(1UL << 31)
 28#define LOONGSON3_PERFCTRL_EVENT(idx, event) \
 29	(((event) & (idx ? 0x0f : 0x3f)) << 5)
 30
 31/* Loongson-3 PerfCount performance counter1 register */
 32#define read_c0_perflo1() __read_64bit_c0_register($25, 0)
 33#define write_c0_perflo1(val) __write_64bit_c0_register($25, 0, val)
 34#define read_c0_perfhi1() __read_64bit_c0_register($25, 1)
 35#define write_c0_perfhi1(val) __write_64bit_c0_register($25, 1, val)
 36
 37/* Loongson-3 PerfCount performance counter2 register */
 38#define read_c0_perflo2() __read_64bit_c0_register($25, 2)
 39#define write_c0_perflo2(val) __write_64bit_c0_register($25, 2, val)
 40#define read_c0_perfhi2() __read_64bit_c0_register($25, 3)
 41#define write_c0_perfhi2(val) __write_64bit_c0_register($25, 3, val)
 42
 43static int (*save_perf_irq)(void);
 44
 45static struct loongson3_register_config {
 46	unsigned int control1;
 47	unsigned int control2;
 48	unsigned long long reset_counter1;
 49	unsigned long long reset_counter2;
 50	int ctr1_enable, ctr2_enable;
 51} reg;
 52
 53static void reset_counters(void *arg)
 54{
 55	write_c0_perfhi1(0);
 56	write_c0_perfhi2(0);
 57	write_c0_perflo1(0xc0000000);
 58	write_c0_perflo2(0x40000000);
 59}
 60
 61/* Compute all of the registers in preparation for enabling profiling. */
 62static void loongson3_reg_setup(struct op_counter_config *ctr)
 63{
 64	unsigned int control1 = 0;
 65	unsigned int control2 = 0;
 66
 67	reg.reset_counter1 = 0;
 68	reg.reset_counter2 = 0;
 69	/* Compute the performance counter control word. */
 70	/* For now count kernel and user mode */
 71	if (ctr[0].enabled) {
 72		control1 |= LOONGSON3_PERFCTRL_EVENT(0, ctr[0].event) |
 73					LOONGSON3_PERFCTRL_ENABLE;
 74		if (ctr[0].kernel)
 75			control1 |= LOONGSON3_PERFCTRL_KERNEL;
 76		if (ctr[0].user)
 77			control1 |= LOONGSON3_PERFCTRL_USER;
 78		reg.reset_counter1 = 0x8000000000000000ULL - ctr[0].count;
 79	}
 80
 81	if (ctr[1].enabled) {
 82		control2 |= LOONGSON3_PERFCTRL_EVENT(1, ctr[1].event) |
 83					LOONGSON3_PERFCTRL_ENABLE;
 84		if (ctr[1].kernel)
 85			control2 |= LOONGSON3_PERFCTRL_KERNEL;
 86		if (ctr[1].user)
 87			control2 |= LOONGSON3_PERFCTRL_USER;
 88		reg.reset_counter2 = 0x8000000000000000ULL - ctr[1].count;
 89	}
 90
 91	if (ctr[0].enabled)
 92		control1 |= LOONGSON3_PERFCTRL_EXL;
 93	if (ctr[1].enabled)
 94		control2 |= LOONGSON3_PERFCTRL_EXL;
 95
 96	reg.control1 = control1;
 97	reg.control2 = control2;
 98	reg.ctr1_enable = ctr[0].enabled;
 99	reg.ctr2_enable = ctr[1].enabled;
100}
101
102/* Program all of the registers in preparation for enabling profiling. */
103static void loongson3_cpu_setup(void *args)
104{
105	uint64_t perfcount1, perfcount2;
106
107	perfcount1 = reg.reset_counter1;
108	perfcount2 = reg.reset_counter2;
109	write_c0_perfhi1(perfcount1);
110	write_c0_perfhi2(perfcount2);
111}
112
113static void loongson3_cpu_start(void *args)
114{
115	/* Start all counters on current CPU */
116	reg.control1 |= (LOONGSON3_PERFCTRL_W|LOONGSON3_PERFCTRL_M);
117	reg.control2 |= (LOONGSON3_PERFCTRL_W|LOONGSON3_PERFCTRL_M);
118
119	if (reg.ctr1_enable)
120		write_c0_perflo1(reg.control1);
121	if (reg.ctr2_enable)
122		write_c0_perflo2(reg.control2);
123}
124
125static void loongson3_cpu_stop(void *args)
126{
127	/* Stop all counters on current CPU */
128	write_c0_perflo1(0xc0000000);
129	write_c0_perflo2(0x40000000);
130	memset(&reg, 0, sizeof(reg));
131}
132
133static int loongson3_perfcount_handler(void)
134{
135	unsigned long flags;
136	uint64_t counter1, counter2;
137	uint32_t cause, handled = IRQ_NONE;
138	struct pt_regs *regs = get_irq_regs();
139
140	cause = read_c0_cause();
141	if (!(cause & CAUSEF_PCI))
142		return handled;
143
144	counter1 = read_c0_perfhi1();
145	counter2 = read_c0_perfhi2();
146
147	local_irq_save(flags);
148
149	if (counter1 & LOONGSON3_PERFCNT_OVERFLOW) {
150		if (reg.ctr1_enable)
151			oprofile_add_sample(regs, 0);
152		counter1 = reg.reset_counter1;
153	}
154	if (counter2 & LOONGSON3_PERFCNT_OVERFLOW) {
155		if (reg.ctr2_enable)
156			oprofile_add_sample(regs, 1);
157		counter2 = reg.reset_counter2;
158	}
159
160	local_irq_restore(flags);
161
162	write_c0_perfhi1(counter1);
163	write_c0_perfhi2(counter2);
164
165	if (!(cause & CAUSEF_TI))
166		handled = IRQ_HANDLED;
167
168	return handled;
169}
170
171static int loongson3_starting_cpu(unsigned int cpu)
172{
173	write_c0_perflo1(reg.control1);
174	write_c0_perflo2(reg.control2);
175	return 0;
176}
177
178static int loongson3_dying_cpu(unsigned int cpu)
179{
180	write_c0_perflo1(0xc0000000);
181	write_c0_perflo2(0x40000000);
182	return 0;
183}
184
185static int __init loongson3_init(void)
186{
187	on_each_cpu(reset_counters, NULL, 1);
188	cpuhp_setup_state_nocalls(CPUHP_AP_MIPS_OP_LOONGSON3_STARTING,
189				  "mips/oprofile/loongson3:starting",
190				  loongson3_starting_cpu, loongson3_dying_cpu);
191	save_perf_irq = perf_irq;
192	perf_irq = loongson3_perfcount_handler;
193
194	return 0;
195}
196
197static void loongson3_exit(void)
198{
199	on_each_cpu(reset_counters, NULL, 1);
200	cpuhp_remove_state_nocalls(CPUHP_AP_MIPS_OP_LOONGSON3_STARTING);
201	perf_irq = save_perf_irq;
202}
203
204struct op_mips_model op_model_loongson3_ops = {
205	.reg_setup	= loongson3_reg_setup,
206	.cpu_setup	= loongson3_cpu_setup,
207	.init		= loongson3_init,
208	.exit		= loongson3_exit,
209	.cpu_start	= loongson3_cpu_start,
210	.cpu_stop	= loongson3_cpu_stop,
211	.cpu_type	= "mips/loongson3",
212	.num_counters	= 2
213};