diff options
Diffstat (limited to 'arch/mips/sibyte/sb1250/bcm1250_tbprof.c')
| -rw-r--r-- | arch/mips/sibyte/sb1250/bcm1250_tbprof.c | 390 |
1 files changed, 390 insertions, 0 deletions
diff --git a/arch/mips/sibyte/sb1250/bcm1250_tbprof.c b/arch/mips/sibyte/sb1250/bcm1250_tbprof.c new file mode 100644 index 0000000..7f813ae --- /dev/null +++ b/arch/mips/sibyte/sb1250/bcm1250_tbprof.c @@ -0,0 +1,390 @@ +/* + * 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 <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 */ + bus_writeq(0, IOADDR(A_SCD_PERF_CNT_1)); + scdperfcnt = bus_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. */ + bus_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)); + bus_writeq(next, IOADDR(A_SCD_PERF_CNT_1)); + /* Reset the trace buffer */ + bus_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 + bus_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 */ + bus_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] = bus_readq(IOADDR(A_SCD_TRACE_READ)); // read t2 hi + p[i-2] = bus_readq(IOADDR(A_SCD_TRACE_READ)); // read t2 lo + p[i-3] = bus_readq(IOADDR(A_SCD_TRACE_READ)); // read t1 hi + p[i-4] = bus_readq(IOADDR(A_SCD_TRACE_READ)); // read t1 lo + p[i-5] = bus_readq(IOADDR(A_SCD_TRACE_READ)); // read t0 hi + p[i-6] = bus_readq(IOADDR(A_SCD_TRACE_READ)); // read t0 lo + } + if (!sbp.tb_enable) { + DBG(printk(DEVNAME ": tb_intr shutdown\n")); + bus_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")); + bus_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 = bus_readq(IOADDR(A_SCD_PERF_CNT_CFG)); + /* Disable and clear counters, override SRC_1 */ + bus_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 */ + bus_writeq(K_INT_MAP_I3, + IOADDR(A_IMR_REGISTER(0, R_IMR_INTERRUPT_MAP_BASE) + + (K_INT_PERF_CNT << 3))); + + /* Initialize address traps */ + bus_writeq(0, IOADDR(A_ADDR_TRAP_UP_0)); + bus_writeq(0, IOADDR(A_ADDR_TRAP_UP_1)); + bus_writeq(0, IOADDR(A_ADDR_TRAP_UP_2)); + bus_writeq(0, IOADDR(A_ADDR_TRAP_UP_3)); + + bus_writeq(0, IOADDR(A_ADDR_TRAP_DOWN_0)); + bus_writeq(0, IOADDR(A_ADDR_TRAP_DOWN_1)); + bus_writeq(0, IOADDR(A_ADDR_TRAP_DOWN_2)); + bus_writeq(0, IOADDR(A_ADDR_TRAP_DOWN_3)); + + bus_writeq(0, IOADDR(A_ADDR_TRAP_CFG_0)); + bus_writeq(0, IOADDR(A_ADDR_TRAP_CFG_1)); + bus_writeq(0, IOADDR(A_ADDR_TRAP_CFG_2)); + bus_writeq(0, IOADDR(A_ADDR_TRAP_CFG_3)); + + /* Initialize Trace Event 0-7 */ + // when interrupt + bus_writeq(M_SCD_TREVT_INTERRUPT, IOADDR(A_SCD_TRACE_EVENT_0)); + bus_writeq(0, IOADDR(A_SCD_TRACE_EVENT_1)); + bus_writeq(0, IOADDR(A_SCD_TRACE_EVENT_2)); + bus_writeq(0, IOADDR(A_SCD_TRACE_EVENT_3)); + bus_writeq(0, IOADDR(A_SCD_TRACE_EVENT_4)); + bus_writeq(0, IOADDR(A_SCD_TRACE_EVENT_5)); + bus_writeq(0, IOADDR(A_SCD_TRACE_EVENT_6)); + bus_writeq(0, IOADDR(A_SCD_TRACE_EVENT_7)); + + /* Initialize Trace Sequence 0-7 */ + // Start on event 0 (interrupt) + bus_writeq(V_SCD_TRSEQ_FUNC_START | 0x0fff, + IOADDR(A_SCD_TRACE_SEQUENCE_0)); + // dsamp when d used | asamp when a used + bus_writeq(M_SCD_TRSEQ_ASAMPLE | M_SCD_TRSEQ_DSAMPLE | + K_SCD_TRSEQ_TRIGGER_ALL, + IOADDR(A_SCD_TRACE_SEQUENCE_1)); + bus_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_2)); + bus_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_3)); + bus_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_4)); + bus_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_5)); + bus_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_6)); + bus_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_7)); + + /* Now indicate the PERF_CNT interrupt as a trace-relevant interrupt */ + bus_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) +{ + 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")); + interruptible_sleep_on(&sbp.tb_sync); + 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 int sbprof_tb_ioctl(struct inode *inode, + struct file *filp, + unsigned int command, + unsigned long arg) +{ + int error = 0; + + switch (command) { + case SBPROF_ZBSTART: + error = sbprof_zbprof_start(filp); + break; + case SBPROF_ZBSTOP: + error = sbprof_zbprof_stop(); + break; + case SBPROF_ZBWAITFULL: + interruptible_sleep_on(&sbp.tb_read); + /* XXXKW check if interrupted? */ + return put_user(TB_FULL, (int *) arg); + default: + error = -EINVAL; + break; + } + + return error; +} + +static struct file_operations sbprof_tb_fops = { + .owner = THIS_MODULE, + .open = sbprof_tb_open, + .release = sbprof_tb_release, + .read = sbprof_tb_read, + .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); |
