acrn-kernel/arch/mips/sibyte/sb1250/bcm1250_tbprof.c

407 lines
12 KiB
C

/*
* Copyright (C) 2001, 2002, 2003 Broadcom Corporation
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#define SBPROF_TB_DEBUG 0
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/reboot.h>
#include <linux/smp_lock.h>
#include <linux/wait.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/sibyte/sb1250.h>
#include <asm/sibyte/sb1250_regs.h>
#include <asm/sibyte/sb1250_scd.h>
#include <asm/sibyte/sb1250_int.h>
#include <asm/sibyte/trace_prof.h>
#define DEVNAME "bcm1250_tbprof"
static struct sbprof_tb sbp;
#define TB_FULL (sbp.next_tb_sample == MAX_TB_SAMPLES)
/************************************************************************
* Support for ZBbus sampling using the trace buffer
*
* We use the SCD performance counter interrupt, caused by a Zclk counter
* overflow, to trigger the start of tracing.
*
* We set the trace buffer to sample everything and freeze on
* overflow.
*
* We map the interrupt for trace_buffer_freeze to handle it on CPU 0.
*
************************************************************************/
static u_int64_t tb_period;
static void arm_tb(void)
{
u_int64_t scdperfcnt;
u_int64_t next = (1ULL << 40) - tb_period;
u_int64_t tb_options = M_SCD_TRACE_CFG_FREEZE_FULL;
/* Generate an SCD_PERFCNT interrupt in TB_PERIOD Zclks to
trigger start of trace. XXX vary sampling period */
__raw_writeq(0, IOADDR(A_SCD_PERF_CNT_1));
scdperfcnt = __raw_readq(IOADDR(A_SCD_PERF_CNT_CFG));
/* Unfortunately, in Pass 2 we must clear all counters to knock down
a previous interrupt request. This means that bus profiling
requires ALL of the SCD perf counters. */
__raw_writeq((scdperfcnt & ~M_SPC_CFG_SRC1) |
// keep counters 0,2,3 as is
M_SPC_CFG_ENABLE | // enable counting
M_SPC_CFG_CLEAR | // clear all counters
V_SPC_CFG_SRC1(1), // counter 1 counts cycles
IOADDR(A_SCD_PERF_CNT_CFG));
__raw_writeq(next, IOADDR(A_SCD_PERF_CNT_1));
/* Reset the trace buffer */
__raw_writeq(M_SCD_TRACE_CFG_RESET, IOADDR(A_SCD_TRACE_CFG));
#if 0 && defined(M_SCD_TRACE_CFG_FORCECNT)
/* XXXKW may want to expose control to the data-collector */
tb_options |= M_SCD_TRACE_CFG_FORCECNT;
#endif
__raw_writeq(tb_options, IOADDR(A_SCD_TRACE_CFG));
sbp.tb_armed = 1;
}
static irqreturn_t sbprof_tb_intr(int irq, void *dev_id, struct pt_regs *regs)
{
int i;
DBG(printk(DEVNAME ": tb_intr\n"));
if (sbp.next_tb_sample < MAX_TB_SAMPLES) {
/* XXX should use XKPHYS to make writes bypass L2 */
u_int64_t *p = sbp.sbprof_tbbuf[sbp.next_tb_sample++];
/* Read out trace */
__raw_writeq(M_SCD_TRACE_CFG_START_READ,
IOADDR(A_SCD_TRACE_CFG));
__asm__ __volatile__ ("sync" : : : "memory");
/* Loop runs backwards because bundles are read out in reverse order */
for (i = 256 * 6; i > 0; i -= 6) {
// Subscripts decrease to put bundle in the order
// t0 lo, t0 hi, t1 lo, t1 hi, t2 lo, t2 hi
p[i - 1] = __raw_readq(IOADDR(A_SCD_TRACE_READ));
// read t2 hi
p[i - 2] = __raw_readq(IOADDR(A_SCD_TRACE_READ));
// read t2 lo
p[i - 3] = __raw_readq(IOADDR(A_SCD_TRACE_READ));
// read t1 hi
p[i - 4] = __raw_readq(IOADDR(A_SCD_TRACE_READ));
// read t1 lo
p[i - 5] = __raw_readq(IOADDR(A_SCD_TRACE_READ));
// read t0 hi
p[i - 6] = __raw_readq(IOADDR(A_SCD_TRACE_READ));
// read t0 lo
}
if (!sbp.tb_enable) {
DBG(printk(DEVNAME ": tb_intr shutdown\n"));
__raw_writeq(M_SCD_TRACE_CFG_RESET,
IOADDR(A_SCD_TRACE_CFG));
sbp.tb_armed = 0;
wake_up(&sbp.tb_sync);
} else {
arm_tb(); // knock down current interrupt and get another one later
}
} else {
/* No more trace buffer samples */
DBG(printk(DEVNAME ": tb_intr full\n"));
__raw_writeq(M_SCD_TRACE_CFG_RESET, IOADDR(A_SCD_TRACE_CFG));
sbp.tb_armed = 0;
if (!sbp.tb_enable) {
wake_up(&sbp.tb_sync);
}
wake_up(&sbp.tb_read);
}
return IRQ_HANDLED;
}
static irqreturn_t sbprof_pc_intr(int irq, void *dev_id, struct pt_regs *regs)
{
printk(DEVNAME ": unexpected pc_intr");
return IRQ_NONE;
}
int sbprof_zbprof_start(struct file *filp)
{
u_int64_t scdperfcnt;
if (sbp.tb_enable)
return -EBUSY;
DBG(printk(DEVNAME ": starting\n"));
sbp.tb_enable = 1;
sbp.next_tb_sample = 0;
filp->f_pos = 0;
if (request_irq
(K_INT_TRACE_FREEZE, sbprof_tb_intr, 0, DEVNAME " trace freeze", &sbp)) {
return -EBUSY;
}
/* Make sure there isn't a perf-cnt interrupt waiting */
scdperfcnt = __raw_readq(IOADDR(A_SCD_PERF_CNT_CFG));
/* Disable and clear counters, override SRC_1 */
__raw_writeq((scdperfcnt & ~(M_SPC_CFG_SRC1 | M_SPC_CFG_ENABLE)) |
M_SPC_CFG_ENABLE | M_SPC_CFG_CLEAR | V_SPC_CFG_SRC1(1),
IOADDR(A_SCD_PERF_CNT_CFG));
/* We grab this interrupt to prevent others from trying to use
it, even though we don't want to service the interrupts
(they only feed into the trace-on-interrupt mechanism) */
if (request_irq
(K_INT_PERF_CNT, sbprof_pc_intr, 0, DEVNAME " scd perfcnt", &sbp)) {
free_irq(K_INT_TRACE_FREEZE, &sbp);
return -EBUSY;
}
/* I need the core to mask these, but the interrupt mapper to
pass them through. I am exploiting my knowledge that
cp0_status masks out IP[5]. krw */
__raw_writeq(K_INT_MAP_I3,
IOADDR(A_IMR_REGISTER(0, R_IMR_INTERRUPT_MAP_BASE) +
(K_INT_PERF_CNT << 3)));
/* Initialize address traps */
__raw_writeq(0, IOADDR(A_ADDR_TRAP_UP_0));
__raw_writeq(0, IOADDR(A_ADDR_TRAP_UP_1));
__raw_writeq(0, IOADDR(A_ADDR_TRAP_UP_2));
__raw_writeq(0, IOADDR(A_ADDR_TRAP_UP_3));
__raw_writeq(0, IOADDR(A_ADDR_TRAP_DOWN_0));
__raw_writeq(0, IOADDR(A_ADDR_TRAP_DOWN_1));
__raw_writeq(0, IOADDR(A_ADDR_TRAP_DOWN_2));
__raw_writeq(0, IOADDR(A_ADDR_TRAP_DOWN_3));
__raw_writeq(0, IOADDR(A_ADDR_TRAP_CFG_0));
__raw_writeq(0, IOADDR(A_ADDR_TRAP_CFG_1));
__raw_writeq(0, IOADDR(A_ADDR_TRAP_CFG_2));
__raw_writeq(0, IOADDR(A_ADDR_TRAP_CFG_3));
/* Initialize Trace Event 0-7 */
// when interrupt
__raw_writeq(M_SCD_TREVT_INTERRUPT, IOADDR(A_SCD_TRACE_EVENT_0));
__raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_1));
__raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_2));
__raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_3));
__raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_4));
__raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_5));
__raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_6));
__raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_7));
/* Initialize Trace Sequence 0-7 */
// Start on event 0 (interrupt)
__raw_writeq(V_SCD_TRSEQ_FUNC_START | 0x0fff,
IOADDR(A_SCD_TRACE_SEQUENCE_0));
// dsamp when d used | asamp when a used
__raw_writeq(M_SCD_TRSEQ_ASAMPLE | M_SCD_TRSEQ_DSAMPLE |
K_SCD_TRSEQ_TRIGGER_ALL,
IOADDR(A_SCD_TRACE_SEQUENCE_1));
__raw_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_2));
__raw_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_3));
__raw_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_4));
__raw_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_5));
__raw_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_6));
__raw_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_7));
/* Now indicate the PERF_CNT interrupt as a trace-relevant interrupt */
__raw_writeq(1ULL << K_INT_PERF_CNT,
IOADDR(A_IMR_REGISTER(0, R_IMR_INTERRUPT_TRACE)));
arm_tb();
DBG(printk(DEVNAME ": done starting\n"));
return 0;
}
int sbprof_zbprof_stop(void)
{
DEFINE_WAIT(wait);
DBG(printk(DEVNAME ": stopping\n"));
if (sbp.tb_enable) {
sbp.tb_enable = 0;
/* XXXKW there is a window here where the intr handler
may run, see the disable, and do the wake_up before
this sleep happens. */
if (sbp.tb_armed) {
DBG(printk(DEVNAME ": wait for disarm\n"));
prepare_to_wait(&sbp.tb_sync, &wait, TASK_INTERRUPTIBLE);
schedule();
finish_wait(&sbp.tb_sync, &wait);
DBG(printk(DEVNAME ": disarm complete\n"));
}
free_irq(K_INT_TRACE_FREEZE, &sbp);
free_irq(K_INT_PERF_CNT, &sbp);
}
DBG(printk(DEVNAME ": done stopping\n"));
return 0;
}
static int sbprof_tb_open(struct inode *inode, struct file *filp)
{
int minor;
minor = iminor(inode);
if (minor != 0) {
return -ENODEV;
}
if (sbp.open) {
return -EBUSY;
}
memset(&sbp, 0, sizeof(struct sbprof_tb));
sbp.sbprof_tbbuf = vmalloc(MAX_TBSAMPLE_BYTES);
if (!sbp.sbprof_tbbuf) {
return -ENOMEM;
}
memset(sbp.sbprof_tbbuf, 0, MAX_TBSAMPLE_BYTES);
init_waitqueue_head(&sbp.tb_sync);
init_waitqueue_head(&sbp.tb_read);
sbp.open = 1;
return 0;
}
static int sbprof_tb_release(struct inode *inode, struct file *filp)
{
int minor;
minor = iminor(inode);
if (minor != 0 || !sbp.open) {
return -ENODEV;
}
if (sbp.tb_armed || sbp.tb_enable) {
sbprof_zbprof_stop();
}
vfree(sbp.sbprof_tbbuf);
sbp.open = 0;
return 0;
}
static ssize_t sbprof_tb_read(struct file *filp, char *buf,
size_t size, loff_t *offp)
{
int cur_sample, sample_off, cur_count, sample_left;
char *src;
int count = 0;
char *dest = buf;
long cur_off = *offp;
count = 0;
cur_sample = cur_off / TB_SAMPLE_SIZE;
sample_off = cur_off % TB_SAMPLE_SIZE;
sample_left = TB_SAMPLE_SIZE - sample_off;
while (size && (cur_sample < sbp.next_tb_sample)) {
cur_count = size < sample_left ? size : sample_left;
src = (char *)(((long)sbp.sbprof_tbbuf[cur_sample])+sample_off);
copy_to_user(dest, src, cur_count);
DBG(printk(DEVNAME ": read from sample %d, %d bytes\n",
cur_sample, cur_count));
size -= cur_count;
sample_left -= cur_count;
if (!sample_left) {
cur_sample++;
sample_off = 0;
sample_left = TB_SAMPLE_SIZE;
} else {
sample_off += cur_count;
}
cur_off += cur_count;
dest += cur_count;
count += cur_count;
}
*offp = cur_off;
return count;
}
static long sbprof_tb_ioctl(struct file *filp,
unsigned int command,
unsigned long arg)
{
int error = 0;
lock_kernel();
switch (command) {
case SBPROF_ZBSTART:
error = sbprof_zbprof_start(filp);
break;
case SBPROF_ZBSTOP:
error = sbprof_zbprof_stop();
break;
case SBPROF_ZBWAITFULL:
DEFINE_WAIT(wait);
prepare_to_wait(&sbp.tb_read, &wait, TASK_INTERRUPTIBLE);
schedule();
finish_wait(&sbp.tb_read, &wait);
/* XXXKW check if interrupted? */
return put_user(TB_FULL, (int *) arg);
default:
error = -EINVAL;
break;
}
unlock_kernel();
return error;
}
static struct file_operations sbprof_tb_fops = {
.owner = THIS_MODULE,
.open = sbprof_tb_open,
.release = sbprof_tb_release,
.read = sbprof_tb_read,
.unlocked_ioctl = sbprof_tb_ioctl,
.compat_ioctl = sbprof_tb_ioctl,
.mmap = NULL,
};
static int __init sbprof_tb_init(void)
{
if (register_chrdev(SBPROF_TB_MAJOR, DEVNAME, &sbprof_tb_fops)) {
printk(KERN_WARNING DEVNAME ": initialization failed (dev %d)\n",
SBPROF_TB_MAJOR);
return -EIO;
}
sbp.open = 0;
tb_period = zbbus_mhz * 10000LL;
printk(KERN_INFO DEVNAME ": initialized - tb_period = %lld\n", tb_period);
return 0;
}
static void __exit sbprof_tb_cleanup(void)
{
unregister_chrdev(SBPROF_TB_MAJOR, DEVNAME);
}
module_init(sbprof_tb_init);
module_exit(sbprof_tb_cleanup);