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authorLinus Torvalds <torvalds@linux-foundation.org>2008-07-14 14:49:54 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-07-14 14:49:54 -0700
commite18425a0abc8eafa8e98ecffac517bb0c0904f4b (patch)
tree5eb743e7201850de19496183554bb34c766948c4 /arch/x86/mm/testmmiotrace.c
parentd1794f2c5b5817eb79ccc5e00701ca748d1b073a (diff)
parent5806b81ac1c0c52665b91723fd4146a4f86e386b (diff)
Merge branch 'tracing/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (228 commits) ftrace: build fix for ftraced_suspend ftrace: separate out the function enabled variable ftrace: add ftrace_kill_atomic ftrace: use current CPU for function startup ftrace: start wakeup tracing after setting function tracer ftrace: check proper config for preempt type ftrace: trace schedule ftrace: define function trace nop ftrace: move sched_switch enable after markers ftrace: prevent ftrace modifications while being kprobe'd, v2 fix "ftrace: store mcount address in rec->ip" mmiotrace broken in linux-next (8-bit writes only) ftrace: avoid modifying kprobe'd records ftrace: freeze kprobe'd records kprobes: enable clean usage of get_kprobe ftrace: store mcount address in rec->ip ftrace: build fix with gcc 4.3 namespacecheck: fixes ftrace: fix "notrace" filtering priority ftrace: fix printout ...
Diffstat (limited to 'arch/x86/mm/testmmiotrace.c')
-rw-r--r--arch/x86/mm/testmmiotrace.c71
1 files changed, 71 insertions, 0 deletions
diff --git a/arch/x86/mm/testmmiotrace.c b/arch/x86/mm/testmmiotrace.c
new file mode 100644
index 000000000000..d877c5b423ef
--- /dev/null
+++ b/arch/x86/mm/testmmiotrace.c
@@ -0,0 +1,71 @@
+/*
+ * Written by Pekka Paalanen, 2008 <pq@iki.fi>
+ */
+#include <linux/module.h>
+#include <linux/io.h>
+
+#define MODULE_NAME "testmmiotrace"
+
+static unsigned long mmio_address;
+module_param(mmio_address, ulong, 0);
+MODULE_PARM_DESC(mmio_address, "Start address of the mapping of 16 kB.");
+
+static void do_write_test(void __iomem *p)
+{
+ unsigned int i;
+ for (i = 0; i < 256; i++)
+ iowrite8(i, p + i);
+ for (i = 1024; i < (5 * 1024); i += 2)
+ iowrite16(i * 12 + 7, p + i);
+ for (i = (5 * 1024); i < (16 * 1024); i += 4)
+ iowrite32(i * 212371 + 13, p + i);
+}
+
+static void do_read_test(void __iomem *p)
+{
+ unsigned int i;
+ for (i = 0; i < 256; i++)
+ ioread8(p + i);
+ for (i = 1024; i < (5 * 1024); i += 2)
+ ioread16(p + i);
+ for (i = (5 * 1024); i < (16 * 1024); i += 4)
+ ioread32(p + i);
+}
+
+static void do_test(void)
+{
+ void __iomem *p = ioremap_nocache(mmio_address, 0x4000);
+ if (!p) {
+ pr_err(MODULE_NAME ": could not ioremap, aborting.\n");
+ return;
+ }
+ do_write_test(p);
+ do_read_test(p);
+ iounmap(p);
+}
+
+static int __init init(void)
+{
+ if (mmio_address == 0) {
+ pr_err(MODULE_NAME ": you have to use the module argument "
+ "mmio_address.\n");
+ pr_err(MODULE_NAME ": DO NOT LOAD THIS MODULE UNLESS"
+ " YOU REALLY KNOW WHAT YOU ARE DOING!\n");
+ return -ENXIO;
+ }
+
+ pr_warning(MODULE_NAME ": WARNING: mapping 16 kB @ 0x%08lx "
+ "in PCI address space, and writing "
+ "rubbish in there.\n", mmio_address);
+ do_test();
+ return 0;
+}
+
+static void __exit cleanup(void)
+{
+ pr_debug(MODULE_NAME ": unloaded.\n");
+}
+
+module_init(init);
+module_exit(cleanup);
+MODULE_LICENSE("GPL");