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authorDavid S. Miller <davem@davemloft.net>2008-07-18 02:39:39 -0700
committerDavid S. Miller <davem@davemloft.net>2008-07-18 02:39:39 -0700
commit49997d75152b3d23c53b0fa730599f2f74c92c65 (patch)
tree46e93126170d02cfec9505172e545732c1b69656 /arch/x86/mm/testmmiotrace.c
parenta0c80b80e0fb48129e4e9d6a9ede914f9ff1850d (diff)
parent5b664cb235e97afbf34db9c4d77f08ebd725335e (diff)
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts: Documentation/powerpc/booting-without-of.txt drivers/atm/Makefile drivers/net/fs_enet/fs_enet-main.c drivers/pci/pci-acpi.c net/8021q/vlan.c net/iucv/iucv.c
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");