patch-2.4.19 linux-2.4.19/arch/mips/sibyte/sb1250/bcm1250_tbprof.c

• Lines: 373
• Date: Fri Aug 2 17:39:43 2002
• Orig file: linux-2.4.18/arch/mips/sibyte/sb1250/bcm1250_tbprof.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -urN linux-2.4.18/arch/mips/sibyte/sb1250/bcm1250_tbprof.c linux-2.4.19/arch/mips/sibyte/sb1250/bcm1250_tbprof.c
@@ -0,0 +1,372 @@
+/*
+ * Copyright (C) 2001 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/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/fs.h>
+#include <linux/errno.h>
+#include <linux/reboot.h>
+#include <linux/devfs_fs_kernel.h>
+#include <asm/uaccess.h>
+#include <asm/smplock.h>
+#include <asm/sibyte/sb1250_regs.h>
+#include <asm/sibyte/sb1250_scd.h>
+#include <asm/sibyte/sb1250_int.h>
+#include <asm/sibyte/64bit.h>
+#include "bcm1250_tbprof.h"
+
+#define DEVNAME "sb1250_tbprof"
+
+static struct sbprof_tb *sbp;
+
+/************************************************************************
+ * 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.
+ * 
+ ************************************************************************/
+
+/* Once per second on a 500 Mhz 1250 */
+#define TB_PERIOD 250000000ULL
+
+static void arm_tb(void)
+{
+	unsigned long long next = (1ULL << 40) - TB_PERIOD;
+	/* Generate an SCD_PERFCNT interrupt in TB_PERIOD Zclks to
+	   trigger start of trace.  XXX vary sampling period */
+	out64(0, KSEG1 + A_SCD_PERF_CNT_1);
+	out64(in64(KSEG1 + A_SCD_PERF_CNT_CFG) | // keep counters 0,2,3 as is
+		   M_SPC_CFG_ENABLE |		 // enable counting
+		   V_SPC_CFG_SRC1(1),		 // counter 1 counts cycles
+	      KSEG1 + A_SCD_PERF_CNT_CFG);
+	out64(next, KSEG1 + A_SCD_PERF_CNT_1);
+	/* Reset the trace buffer */
+	out64(M_SCD_TRACE_CFG_RESET, KSEG1 + A_SCD_TRACE_CFG);
+	out64(M_SCD_TRACE_CFG_FREEZE_FULL, KSEG1 + A_SCD_TRACE_CFG);
+	sbp->tb_armed = 1;
+}
+
+static void 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 */
+		unsigned long long *p = sbp->sbprof_tbbuf[sbp->next_tb_sample++];
+		/* Read out trace */
+		out64(M_SCD_TRACE_CFG_START_READ, KSEG1 + 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] = in64(KSEG1 + A_SCD_TRACE_READ); // read t2 hi
+			p[i-2] = in64(KSEG1 + A_SCD_TRACE_READ); // read t2 lo
+			p[i-3] = in64(KSEG1 + A_SCD_TRACE_READ); // read t1 hi
+			p[i-4] = in64(KSEG1 + A_SCD_TRACE_READ); // read t1 lo
+			p[i-5] = in64(KSEG1 + A_SCD_TRACE_READ); // read t0 hi
+			p[i-6] = in64(KSEG1 + A_SCD_TRACE_READ); // read t0 lo
+		}
+		if (!sbp->tb_enable) {
+			DBG(printk(DEVNAME ": tb_intr shutdown\n"));
+			out64(M_SCD_TRACE_CFG_RESET, KSEG1 + 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"));
+		out64(M_SCD_TRACE_CFG_RESET, KSEG1 + A_SCD_TRACE_CFG);
+		sbp->tb_armed = 0;
+		if (!sbp->tb_enable) {
+			wake_up(&sbp->tb_sync);
+		}
+	}
+}
+
+static void sbprof_pc_intr(int irq, void *dev_id, struct pt_regs *regs)
+{
+	panic(DEVNAME ": pc_intr");
+}
+
+static int sbprof_zbprof_start(struct file *filp)
+{
+	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, "sbprof_tb trace freeze", sbp)) {
+		return -EBUSY;
+	}
+	if (request_irq
+	    (K_INT_PERF_CNT, sbprof_pc_intr, 0, "sbprof_tb 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 */
+	out64(K_INT_MAP_I3,
+	      KSEG1 + A_IMR_REGISTER(0, R_IMR_INTERRUPT_MAP_BASE) + (K_INT_PERF_CNT<<3));
+
+	/* Initialize address traps */
+	out64(0, KSEG1 + A_ADDR_TRAP_UP_0);
+	out64(0, KSEG1 + A_ADDR_TRAP_UP_1);
+	out64(0, KSEG1 + A_ADDR_TRAP_UP_2);
+	out64(0, KSEG1 + A_ADDR_TRAP_UP_3);
+	
+	out64(0, KSEG1 + A_ADDR_TRAP_DOWN_0);
+	out64(0, KSEG1 + A_ADDR_TRAP_DOWN_1);
+	out64(0, KSEG1 + A_ADDR_TRAP_DOWN_2);
+	out64(0, KSEG1 + A_ADDR_TRAP_DOWN_3);
+	
+	out64(0, KSEG1 + A_ADDR_TRAP_CFG_0);
+	out64(0, KSEG1 + A_ADDR_TRAP_CFG_1);
+	out64(0, KSEG1 + A_ADDR_TRAP_CFG_2);
+	out64(0, KSEG1 + A_ADDR_TRAP_CFG_3);
+	
+	/* Initialize Trace Event 0-7 */
+	//				when interrupt
+	out64(M_SCD_TREVT_INTERRUPT, KSEG1 + A_SCD_TRACE_EVENT_0);
+	out64(0, KSEG1 + A_SCD_TRACE_EVENT_1);
+	out64(0, KSEG1 + A_SCD_TRACE_EVENT_2);
+	out64(0, KSEG1 + A_SCD_TRACE_EVENT_3);
+	out64(0, KSEG1 + A_SCD_TRACE_EVENT_4);
+	out64(0, KSEG1 + A_SCD_TRACE_EVENT_5);
+	out64(0, KSEG1 + A_SCD_TRACE_EVENT_6);
+	out64(0, KSEG1 + A_SCD_TRACE_EVENT_7);
+	
+	/* Initialize Trace Sequence 0-7 */
+	//				     Start on event 0 (interrupt)
+	out64(V_SCD_TRSEQ_FUNC_START|0x0fff,
+	      KSEG1 + A_SCD_TRACE_SEQUENCE_0);
+	//			  dsamp when d used | asamp when a used
+	out64(M_SCD_TRSEQ_ASAMPLE|M_SCD_TRSEQ_DSAMPLE|K_SCD_TRSEQ_TRIGGER_ALL,
+	      KSEG1 + A_SCD_TRACE_SEQUENCE_1);
+	out64(0, KSEG1 + A_SCD_TRACE_SEQUENCE_2);
+	out64(0, KSEG1 + A_SCD_TRACE_SEQUENCE_3);
+	out64(0, KSEG1 + A_SCD_TRACE_SEQUENCE_4);
+	out64(0, KSEG1 + A_SCD_TRACE_SEQUENCE_5);
+	out64(0, KSEG1 + A_SCD_TRACE_SEQUENCE_6);
+	out64(0, KSEG1 + A_SCD_TRACE_SEQUENCE_7);
+
+	/* Now indicate the PERF_CNT interrupt as a trace-relevant interrupt */
+	out64((1ULL << K_INT_PERF_CNT), KSEG1 + A_IMR_REGISTER(0, R_IMR_INTERRUPT_TRACE));
+
+	arm_tb();
+
+	DBG(printk(DEVNAME ": done starting\n"));
+
+	return 0;
+}
+
+static 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 = MINOR(inode->i_rdev);
+	if (minor != 0) {
+		return -ENODEV;
+	}
+	if (sbp != NULL) {
+		return -EBUSY;
+	}
+
+	/* XXXKW spinlock? */
+	sbp = kmalloc(sizeof(struct sbprof_tb), GFP_KERNEL);
+	if (!sbp) {
+		return -ENOMEM;
+	}
+	memset(sbp, 0, sizeof(struct sbprof_tb));
+	sbp->sbprof_tbbuf = vmalloc(MAX_TBSAMPLE_BYTES);
+	if (!sbp->sbprof_tbbuf) {
+		kfree(sbp);
+		sbp = NULL;
+		return -ENOMEM;
+	}
+	memset(sbp->sbprof_tbbuf, 0, MAX_TBSAMPLE_BYTES);
+	init_waitqueue_head(&sbp->tb_sync);
+
+	return 0;
+}
+
+static int sbprof_tb_release(struct inode *inode, struct file *filp)
+{
+	int minor;
+	
+	minor = MINOR(inode->i_rdev);
+	if (minor != 0 || sbp == NULL) {
+		return -ENODEV;
+	}
+
+	if (sbp->tb_armed || sbp->tb_enable) {
+		sbprof_zbprof_stop();
+	}
+
+	vfree(sbp->sbprof_tbbuf);
+	kfree(sbp);
+	sbp = NULL;
+
+	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;
+}
+
+#define SBPROF_ZBSTART	_IOW('s', 0, int)
+#define SBPROF_ZBSTOP	_IOW('s', 1, int)
+#define SBPROF_ZBFULL	_IOW('s', 2, int)
+
+static int sbprof_tb_ioctl(struct inode *inode, 
+			struct file *filp,
+			unsigned int command, 
+			unsigned long arg)
+{
+	int error = 0;
+	int full;
+
+	switch (command) {
+	case SBPROF_ZBSTART:
+		error = sbprof_zbprof_start(filp);
+		break;
+	case SBPROF_ZBSTOP:
+		error = sbprof_zbprof_stop();
+		break;
+	case SBPROF_ZBFULL:
+		full = (sbp->next_tb_sample == MAX_TB_SAMPLES);
+		return put_user(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 devfs_handle_t devfs_handle;
+
+static int __init sbprof_tb_init(void) 
+{
+	if (devfs_register_chrdev(SBPROF_TB_MAJOR, DEVNAME, &sbprof_tb_fops)) {
+		printk(KERN_WARNING DEVNAME ": initialization failed (dev %d)\n",
+		       SBPROF_TB_MAJOR);
+		return -EIO;
+	}
+	devfs_handle = devfs_register(NULL, DEVNAME,
+				      DEVFS_FL_DEFAULT, SBPROF_TB_MAJOR, 0,
+				      S_IFCHR | S_IRUGO | S_IWUGO,
+				      &sbprof_tb_fops, NULL);
+	sbp = NULL;
+	printk(KERN_INFO DEVNAME ": initialized\n");
+	return 0;
+}
+
+static void __exit sbprof_tb_cleanup(void)
+{
+	devfs_unregister_chrdev(SBPROF_TB_MAJOR, DEVNAME);
+	devfs_unregister(devfs_handle);
+}
+
+module_init(sbprof_tb_init);
+module_exit(sbprof_tb_cleanup);