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authorRalf Baechle <ralf@linux-mips.org>2007-03-09 15:59:56 +0000
committerRalf Baechle <ralf@linux-mips.org>2007-03-09 20:27:31 +0000
commitbb9b813bb665cdbe7019a4f1e93f7138e7bf59d0 (patch)
treee16ef7f87c90a90e02fd501cf1472ce77ee02c30 /arch/mips/sibyte/sb1250
parentca6f5494f5e0ff60675d99b51c4c56921d95fe1d (diff)
[MIPS] Sibyte: Fix ZBbus profiler
o Fix build error. o Handle error returns. o Deal with signals received while sleeping. o Don't allow to be selected when we're not building the directory with the driver anyway. o Coding style cleanups. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/sibyte/sb1250')
-rw-r--r--arch/mips/sibyte/sb1250/bcm1250_tbprof.c377
-rw-r--r--arch/mips/sibyte/sb1250/setup.c2
2 files changed, 273 insertions, 106 deletions
diff --git a/arch/mips/sibyte/sb1250/bcm1250_tbprof.c b/arch/mips/sibyte/sb1250/bcm1250_tbprof.c
index 212547c5731..ea0ca131a3c 100644
--- a/arch/mips/sibyte/sb1250/bcm1250_tbprof.c
+++ b/arch/mips/sibyte/sb1250/bcm1250_tbprof.c
@@ -1,6 +1,4 @@
/*
- * 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
@@ -14,10 +12,16 @@
* 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.
+ *
+ * Copyright (C) 2001, 2002, 2003 Broadcom Corporation
+ * Copyright (C) 2007 Ralf Baechle <ralf@linux-mips.org>
+ * Copyright (C) 2007 MIPS Technologies, Inc.
+ * written by Ralf Baechle <ralf@linux-mips.org>
*/
-#define SBPROF_TB_DEBUG 0
+#undef DEBUG
+#include <linux/device.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
@@ -27,24 +31,98 @@
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <linux/errno.h>
-#include <linux/reboot.h>
-#include <linux/smp_lock.h>
+#include <linux/types.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>
+#include <asm/system.h>
+#include <asm/uaccess.h>
-#define DEVNAME "bcm1250_tbprof"
+#define SBPROF_TB_MAJOR 240
+
+typedef u64 tb_sample_t[6*256];
+
+enum open_status {
+ SB_CLOSED,
+ SB_OPENING,
+ SB_OPEN
+};
+
+struct sbprof_tb {
+ wait_queue_head_t tb_sync;
+ wait_queue_head_t tb_read;
+ struct mutex lock;
+ enum open_status open;
+ tb_sample_t *sbprof_tbbuf;
+ int next_tb_sample;
+
+ volatile int tb_enable;
+ volatile int tb_armed;
+
+};
static struct sbprof_tb sbp;
+#define MAX_SAMPLE_BYTES (24*1024*1024)
+#define MAX_TBSAMPLE_BYTES (12*1024*1024)
+
+#define MAX_SAMPLES (MAX_SAMPLE_BYTES/sizeof(u_int32_t))
+#define TB_SAMPLE_SIZE (sizeof(tb_sample_t))
+#define MAX_TB_SAMPLES (MAX_TBSAMPLE_BYTES/TB_SAMPLE_SIZE)
+
+/* ioctls */
+#define SBPROF_ZBSTART _IOW('s', 0, int)
+#define SBPROF_ZBSTOP _IOW('s', 1, int)
+#define SBPROF_ZBWAITFULL _IOW('s', 2, int)
+
+/*
+ * Routines for using 40-bit SCD cycle counter
+ *
+ * Client responsible for either handling interrupts or making sure
+ * the cycles counter never saturates, e.g., by doing
+ * zclk_timer_init(0) at least every 2^40 - 1 ZCLKs.
+ */
+
+/*
+ * Configures SCD counter 0 to count ZCLKs starting from val;
+ * Configures SCD counters1,2,3 to count nothing.
+ * Must not be called while gathering ZBbus profiles.
+ */
+
+#define zclk_timer_init(val) \
+ __asm__ __volatile__ (".set push;" \
+ ".set mips64;" \
+ "la $8, 0xb00204c0;" /* SCD perf_cnt_cfg */ \
+ "sd %0, 0x10($8);" /* write val to counter0 */ \
+ "sd %1, 0($8);" /* config counter0 for zclks*/ \
+ ".set pop" \
+ : /* no outputs */ \
+ /* enable, counter0 */ \
+ : /* inputs */ "r"(val), "r" ((1ULL << 33) | 1ULL) \
+ : /* modifies */ "$8" )
+
+
+/* Reads SCD counter 0 and puts result in value
+ unsigned long long val; */
+#define zclk_get(val) \
+ __asm__ __volatile__ (".set push;" \
+ ".set mips64;" \
+ "la $8, 0xb00204c0;" /* SCD perf_cnt_cfg */ \
+ "ld %0, 0x10($8);" /* write val to counter0 */ \
+ ".set pop" \
+ : /* outputs */ "=r"(val) \
+ : /* inputs */ \
+ : /* modifies */ "$8" )
+
+#define DEVNAME "bcm1250_tbprof"
+
#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
@@ -54,30 +132,36 @@ static struct sbprof_tb sbp;
* overflow.
*
* We map the interrupt for trace_buffer_freeze to handle it on CPU 0.
- *
- ************************************************************************/
+ */
-static u_int64_t tb_period;
+static u64 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 */
+ u64 scdperfcnt;
+ u64 next = (1ULL << 40) - tb_period;
+ u64 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. */
+
+ /*
+ * 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
+ /* 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)
@@ -91,43 +175,45 @@ static void arm_tb(void)
static irqreturn_t sbprof_tb_intr(int irq, void *dev_id)
{
int i;
- DBG(printk(DEVNAME ": tb_intr\n"));
+
+ pr_debug(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++];
+ u64 *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
+ /* 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
+ /* read t2 hi */
p[i - 2] = __raw_readq(IOADDR(A_SCD_TRACE_READ));
- // read t2 lo
+ /* read t2 lo */
p[i - 3] = __raw_readq(IOADDR(A_SCD_TRACE_READ));
- // read t1 hi
+ /* read t1 hi */
p[i - 4] = __raw_readq(IOADDR(A_SCD_TRACE_READ));
- // read t1 lo
+ /* read t1 lo */
p[i - 5] = __raw_readq(IOADDR(A_SCD_TRACE_READ));
- // read t0 hi
+ /* read t0 hi */
p[i - 6] = __raw_readq(IOADDR(A_SCD_TRACE_READ));
- // read t0 lo
+ /* read t0 lo */
}
if (!sbp.tb_enable) {
- DBG(printk(DEVNAME ": tb_intr shutdown\n"));
+ pr_debug(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
+ arm_tb(); /* knock down current interrupt and get another one later */
}
} else {
/* No more trace buffer samples */
- DBG(printk(DEVNAME ": tb_intr full\n"));
+ pr_debug(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) {
@@ -135,6 +221,7 @@ static irqreturn_t sbprof_tb_intr(int irq, void *dev_id)
}
wake_up(&sbp.tb_read);
}
+
return IRQ_HANDLED;
}
@@ -144,23 +231,30 @@ static irqreturn_t sbprof_pc_intr(int irq, void *dev_id)
return IRQ_NONE;
}
-int sbprof_zbprof_start(struct file *filp)
+/*
+ * Requires: Already called zclk_timer_init with a value that won't
+ * saturate 40 bits. No subsequent use of SCD performance counters
+ * or trace buffer.
+ */
+
+static int sbprof_zbprof_start(struct file *filp)
{
- u_int64_t scdperfcnt;
+ u64 scdperfcnt;
+ int err;
- if (sbp.tb_enable)
+ if (xchg(&sbp.tb_enable, 1))
return -EBUSY;
- DBG(printk(DEVNAME ": starting\n"));
+ pr_debug(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)) {
+ err = request_irq(K_INT_TRACE_FREEZE, sbprof_tb_intr, 0,
+ DEVNAME " trace freeze", &sbp);
+ if (err)
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 */
@@ -168,18 +262,21 @@ int sbprof_zbprof_start(struct file *filp)
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 */
+ /*
+ * 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)
+ */
+ err = request_irq(K_INT_PERF_CNT, sbprof_pc_intr, 0,
+ DEVNAME " scd perfcnt", &sbp);
+ if (err)
+ goto out_free_irq;
+
+ /*
+ * 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)));
@@ -201,7 +298,7 @@ int sbprof_zbprof_start(struct file *filp)
__raw_writeq(0, IOADDR(A_ADDR_TRAP_CFG_3));
/* Initialize Trace Event 0-7 */
- // when interrupt
+ /* 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));
@@ -212,10 +309,10 @@ int sbprof_zbprof_start(struct file *filp)
__raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_7));
/* Initialize Trace Sequence 0-7 */
- // Start on event 0 (interrupt)
+ /* 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
+ /* 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));
@@ -232,33 +329,41 @@ int sbprof_zbprof_start(struct file *filp)
arm_tb();
- DBG(printk(DEVNAME ": done starting\n"));
+ pr_debug(DEVNAME ": done starting\n");
return 0;
+
+out_free_irq:
+ free_irq(K_INT_TRACE_FREEZE, &sbp);
+
+ return err;
}
-int sbprof_zbprof_stop(void)
+static int sbprof_zbprof_stop(void)
{
- DEFINE_WAIT(wait);
- DBG(printk(DEVNAME ": stopping\n"));
+ int err;
+
+ pr_debug(DEVNAME ": stopping\n");
if (sbp.tb_enable) {
+ /*
+ * XXXKW there is a window here where the intr handler may run,
+ * see the disable, and do the wake_up before this sleep
+ * happens.
+ */
+ pr_debug(DEVNAME ": wait for disarm\n");
+ err = wait_event_interruptible(sbp.tb_sync, !sbp.tb_armed);
+ pr_debug(DEVNAME ": disarm complete, stat %d\n", err);
+
+ if (err)
+ return err;
+
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"));
+ pr_debug(DEVNAME ": done stopping\n");
return 0;
}
@@ -268,42 +373,45 @@ static int sbprof_tb_open(struct inode *inode, struct file *filp)
int minor;
minor = iminor(inode);
- if (minor != 0) {
+ if (minor != 0)
return -ENODEV;
- }
- if (sbp.open) {
+
+ if (xchg(&sbp.open, SB_OPENING) != SB_CLOSED)
return -EBUSY;
- }
memset(&sbp, 0, sizeof(struct sbprof_tb));
+
sbp.sbprof_tbbuf = vmalloc(MAX_TBSAMPLE_BYTES);
- if (!sbp.sbprof_tbbuf) {
+ 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;
+ mutex_init(&sbp.lock);
+
+ sbp.open = SB_OPEN;
return 0;
}
static int sbprof_tb_release(struct inode *inode, struct file *filp)
{
- int minor;
+ int minor = iminor(inode);
- minor = iminor(inode);
- if (minor != 0 || !sbp.open) {
+ if (minor != 0 || !sbp.open)
return -ENODEV;
- }
- if (sbp.tb_armed || sbp.tb_enable) {
+ mutex_lock(&sbp.lock);
+
+ if (sbp.tb_armed || sbp.tb_enable)
sbprof_zbprof_stop();
- }
vfree(sbp.sbprof_tbbuf);
sbp.open = 0;
+ mutex_unlock(&sbp.lock);
+
return 0;
}
@@ -311,21 +419,35 @@ 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;
+ char *dest = buf;
+ int count = 0;
+ char *src;
+
+ if (!access_ok(VERIFY_WRITE, buf, size))
+ return -EFAULT;
+
+ mutex_lock(&sbp.lock);
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)) {
+ int err;
+
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));
+ err = __copy_to_user(dest, src, cur_count);
+ if (err) {
+ *offp = cur_off + cur_count - err;
+ mutex_unlock(&sbp.lock);
+ return err;
+ }
+
+ pr_debug(DEVNAME ": read from sample %d, %d bytes\n",
+ cur_sample, cur_count);
size -= cur_count;
sample_left -= cur_count;
if (!sample_left) {
@@ -339,37 +461,43 @@ static ssize_t sbprof_tb_read(struct file *filp, char *buf,
dest += cur_count;
count += cur_count;
}
+
*offp = cur_off;
+ mutex_unlock(&sbp.lock);
return count;
}
-static long sbprof_tb_ioctl(struct file *filp,
- unsigned int command,
- unsigned long arg)
+static long sbprof_tb_ioctl(struct file *filp, unsigned int command,
+ unsigned long arg)
{
int error = 0;
- lock_kernel();
switch (command) {
case SBPROF_ZBSTART:
+ mutex_lock(&sbp.lock);
error = sbprof_zbprof_start(filp);
+ mutex_unlock(&sbp.lock);
break;
+
case SBPROF_ZBSTOP:
+ mutex_lock(&sbp.lock);
error = sbprof_zbprof_stop();
+ mutex_unlock(&sbp.lock);
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);
+ error = wait_event_interruptible(sbp.tb_read, TB_FULL);
+ if (error)
+ break;
+
+ error = put_user(TB_FULL, (int *) arg);
+ break;
+
default:
error = -EINVAL;
break;
}
- unlock_kernel();
return error;
}
@@ -384,23 +512,60 @@ static const struct file_operations sbprof_tb_fops = {
.mmap = NULL,
};
+static struct class *tb_class;
+static struct device *tb_dev;
+
static int __init sbprof_tb_init(void)
{
+ struct device *dev;
+ struct class *tbc;
+ int err;
+
if (register_chrdev(SBPROF_TB_MAJOR, DEVNAME, &sbprof_tb_fops)) {
printk(KERN_WARNING DEVNAME ": initialization failed (dev %d)\n",
SBPROF_TB_MAJOR);
return -EIO;
}
+
+ tbc = class_create(THIS_MODULE, "sb_tracebuffer");
+ if (IS_ERR(tbc)) {
+ err = PTR_ERR(tbc);
+ goto out_chrdev;
+ }
+
+ tb_class = tbc;
+
+ dev = device_create(tbc, NULL, MKDEV(SBPROF_TB_MAJOR, 0), "tb");
+ if (IS_ERR(dev)) {
+ err = PTR_ERR(dev);
+ goto out_class;
+ }
+ tb_dev = dev;
+
sbp.open = 0;
tb_period = zbbus_mhz * 10000LL;
- printk(KERN_INFO DEVNAME ": initialized - tb_period = %lld\n", tb_period);
+ pr_info(DEVNAME ": initialized - tb_period = %lld\n", tb_period);
+
return 0;
+
+out_class:
+ class_destroy(tb_class);
+out_chrdev:
+ unregister_chrdev(SBPROF_TB_MAJOR, DEVNAME);
+
+ return err;
}
static void __exit sbprof_tb_cleanup(void)
{
+ device_destroy(tb_class, MKDEV(SBPROF_TB_MAJOR, 0));
unregister_chrdev(SBPROF_TB_MAJOR, DEVNAME);
+ class_destroy(tb_class);
}
module_init(sbprof_tb_init);
module_exit(sbprof_tb_cleanup);
+
+MODULE_ALIAS_CHARDEV_MAJOR(SBPROF_TB_MAJOR);
+MODULE_AUTHOR("Ralf Baechle <ralf@linux-mips.org>");
+MODULE_LICENSE("GPL");
diff --git a/arch/mips/sibyte/sb1250/setup.c b/arch/mips/sibyte/sb1250/setup.c
index 1cb042eab72..87188f0f6fb 100644
--- a/arch/mips/sibyte/sb1250/setup.c
+++ b/arch/mips/sibyte/sb1250/setup.c
@@ -16,6 +16,7 @@
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <linux/init.h>
+#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/reboot.h>
#include <linux/string.h>
@@ -32,6 +33,7 @@ unsigned int soc_pass;
unsigned int soc_type;
unsigned int periph_rev;
unsigned int zbbus_mhz;
+EXPORT_SYMBOL(zbbus_mhz);
static char *soc_str;
static char *pass_str;