Patchwork [3/3,-v3] MTD: Add nand_ecc test module

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Submitter Akinobu Mita
Date Oct. 21, 2009, 8:34 a.m.
Message ID <1256114044-12163-3-git-send-email-akinobu.mita@gmail.com>
Download mbox | patch
Permalink /patch/36496/
State New
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Comments

Akinobu Mita - Oct. 21, 2009, 8:34 a.m.
This module tests NAND ECC functions.

The test is simple.

1. Create a 256 or 512 bytes block of data filled with random bytes (data)
2. Duplicate the data block and inject single bit error (error_data)
3. Try to correct error_data
4. Compare data and error_data

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: linux-mtd@lists.infradead.org
Cc: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Cc: vimal singh <vimal.newwork@gmail.com>
---
 drivers/mtd/tests/Makefile        |    1 +
 drivers/mtd/tests/nand_ecc-test.c |   87 +++++++++++++++++++++++++++++++++++++
 2 files changed, 88 insertions(+), 0 deletions(-)
 create mode 100644 drivers/mtd/tests/nand_ecc-test.c
Artem Bityutskiy - Oct. 21, 2009, 8:51 a.m.
On Wed, 2009-10-21 at 17:34 +0900, Akinobu Mita wrote:
> This module tests NAND ECC functions.
> 
> The test is simple.
> 
> 1. Create a 256 or 512 bytes block of data filled with random bytes (data)
> 2. Duplicate the data block and inject single bit error (error_data)
> 3. Try to correct error_data
> 4. Compare data and error_data
> 
> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
> Cc: David Woodhouse <dwmw2@infradead.org>
> Cc: linux-mtd@lists.infradead.org
> Cc: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
> Cc: vimal singh <vimal.newwork@gmail.com>
> ---
>  drivers/mtd/tests/Makefile        |    1 +
>  drivers/mtd/tests/nand_ecc-test.c |   87 +++++++++++++++++++++++++++++++++++++
>  2 files changed, 88 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/mtd/tests/nand_ecc-test.c

How about a consistent name for the test? All current tests have 'mtd_'
prefix. How about make the file to be 'mtd_ecctest.c' ?

Also, since you anyway need to use these "#defines", I think there is
not need to use this splitting. I apologize for leading you that way at
the beginning.
vimal singh - Oct. 21, 2009, 9:06 a.m.
On Wed, Oct 21, 2009 at 2:21 PM, Artem Bityutskiy
<Artem.Bityutskiy@nokia.com> wrote:
> On Wed, 2009-10-21 at 17:34 +0900, Akinobu Mita wrote:
>> This module tests NAND ECC functions.
>>
>> The test is simple.
>>
>> 1. Create a 256 or 512 bytes block of data filled with random bytes (data)
>> 2. Duplicate the data block and inject single bit error (error_data)
>> 3. Try to correct error_data
>> 4. Compare data and error_data
>>
>> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
>> Cc: David Woodhouse <dwmw2@infradead.org>
>> Cc: linux-mtd@lists.infradead.org
>> Cc: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
>> Cc: vimal singh <vimal.newwork@gmail.com>
>> ---
>>  drivers/mtd/tests/Makefile        |    1 +
>>  drivers/mtd/tests/nand_ecc-test.c |   87 +++++++++++++++++++++++++++++++++++++
>>  2 files changed, 88 insertions(+), 0 deletions(-)
>>  create mode 100644 drivers/mtd/tests/nand_ecc-test.c
>
> How about a consistent name for the test? All current tests have 'mtd_'
> prefix. How about make the file to be 'mtd_ecctest.c' ?

Or 'mtd_nandecctest.c'..? Since, anyways, this test is only for nand.
Artem Bityutskiy - Oct. 21, 2009, 9:43 a.m.
On Wed, 2009-10-21 at 14:36 +0530, vimal singh wrote:
> > How about a consistent name for the test? All current tests have 'mtd_'
> > prefix. How about make the file to be 'mtd_ecctest.c' ?
> 
> Or 'mtd_nandecctest.c'..? Since, anyways, this test is only for nand.

Fair enough.
Akinobu Mita - Oct. 22, 2009, 3:24 a.m.
On Wed, Oct 21, 2009 at 11:51:35AM +0300, Artem Bityutskiy wrote:
> On Wed, 2009-10-21 at 17:34 +0900, Akinobu Mita wrote:
> > This module tests NAND ECC functions.
> > 
> > The test is simple.
> > 
> > 1. Create a 256 or 512 bytes block of data filled with random bytes (data)
> > 2. Duplicate the data block and inject single bit error (error_data)
> > 3. Try to correct error_data
> > 4. Compare data and error_data
> > 
> > Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
> > Cc: David Woodhouse <dwmw2@infradead.org>
> > Cc: linux-mtd@lists.infradead.org
> > Cc: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
> > Cc: vimal singh <vimal.newwork@gmail.com>
> > ---
> >  drivers/mtd/tests/Makefile        |    1 +
> >  drivers/mtd/tests/nand_ecc-test.c |   87 +++++++++++++++++++++++++++++++++++++
> >  2 files changed, 88 insertions(+), 0 deletions(-)
> >  create mode 100644 drivers/mtd/tests/nand_ecc-test.c
> 
> How about a consistent name for the test? All current tests have 'mtd_'
> prefix. How about make the file to be 'mtd_ecctest.c' ?

OK. I'll rename to mtd_nandecctest.c as vimal said.

> Also, since you anyway need to use these "#defines", I think there is
> not need to use this splitting. I apologize for leading you that way at
> the beginning.

Does it mean we don't need MTD_NAND_TESTS and the new mtd_nandecctest
should exist in MTD_TESTS with that #ifdef checks as I originally did?
Artem Bityutskiy - Oct. 22, 2009, 5:13 a.m.
On Thu, 2009-10-22 at 05:24 +0200, ext Akinobu Mita wrote:
> On Wed, Oct 21, 2009 at 11:51:35AM +0300, Artem Bityutskiy wrote:
> > On Wed, 2009-10-21 at 17:34 +0900, Akinobu Mita wrote:
> > > This module tests NAND ECC functions.
> > > 
> > > The test is simple.
> > > 
> > > 1. Create a 256 or 512 bytes block of data filled with random bytes (data)
> > > 2. Duplicate the data block and inject single bit error (error_data)
> > > 3. Try to correct error_data
> > > 4. Compare data and error_data
> > > 
> > > Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
> > > Cc: David Woodhouse <dwmw2@infradead.org>
> > > Cc: linux-mtd@lists.infradead.org
> > > Cc: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
> > > Cc: vimal singh <vimal.newwork@gmail.com>
> > > ---
> > >  drivers/mtd/tests/Makefile        |    1 +
> > >  drivers/mtd/tests/nand_ecc-test.c |   87 +++++++++++++++++++++++++++++++++++++
> > >  2 files changed, 88 insertions(+), 0 deletions(-)
> > >  create mode 100644 drivers/mtd/tests/nand_ecc-test.c
> > 
> > How about a consistent name for the test? All current tests have 'mtd_'
> > prefix. How about make the file to be 'mtd_ecctest.c' ?
> 
> OK. I'll rename to mtd_nandecctest.c as vimal said.
> 
> > Also, since you anyway need to use these "#defines", I think there is
> > not need to use this splitting. I apologize for leading you that way at
> > the beginning.
> 
> Does it mean we don't need MTD_NAND_TESTS and the new mtd_nandecctest
> should exist in MTD_TESTS with that #ifdef checks as I originally did?

Right. The idea was to avoid the ifdefs by cheap price, but now it seems
that was bad idea.

Patch

diff --git a/drivers/mtd/tests/Makefile b/drivers/mtd/tests/Makefile
index 919d066..8371b60 100644
--- a/drivers/mtd/tests/Makefile
+++ b/drivers/mtd/tests/Makefile
@@ -5,3 +5,4 @@  obj-$(CONFIG_MTD_TESTS) += mtd_torturetest.o
 obj-$(CONFIG_MTD_NAND_TESTS) += mtd_oobtest.o
 obj-$(CONFIG_MTD_NAND_TESTS) += mtd_pagetest.o
 obj-$(CONFIG_MTD_NAND_TESTS) += mtd_subpagetest.o
+obj-$(CONFIG_MTD_NAND_TESTS) += nand_ecc-test.o
diff --git a/drivers/mtd/tests/nand_ecc-test.c b/drivers/mtd/tests/nand_ecc-test.c
new file mode 100644
index 0000000..63ae856
--- /dev/null
+++ b/drivers/mtd/tests/nand_ecc-test.c
@@ -0,0 +1,87 @@ 
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/random.h>
+#include <linux/string.h>
+#include <linux/bitops.h>
+#include <linux/jiffies.h>
+#include <linux/mtd/nand_ecc.h>
+
+#if defined(CONFIG_MTD_NAND) || defined(CONFIG_MTD_NAND_MODULE)
+
+static void inject_single_bit_error(void *data, size_t size)
+{
+	unsigned long offset = random32() % (size * BITS_PER_BYTE);
+
+	__change_bit(offset, data);
+}
+
+static unsigned char data[512];
+static unsigned char error_data[512];
+
+static int nand_ecc_test(const size_t size)
+{
+	unsigned char code[3];
+	unsigned char error_code[3];
+	char testname[30];
+
+	BUG_ON(sizeof(data) < size);
+
+	sprintf(testname, "nand-ecc-%zu", size);
+
+	get_random_bytes(data, size);
+
+	memcpy(error_data, data, size);
+	inject_single_bit_error(error_data, size);
+
+	__nand_calculate_ecc(data, size, code);
+	__nand_calculate_ecc(error_data, size, error_code);
+	__nand_correct_data(error_data, code, error_code, size);
+
+	if (!memcmp(data, error_data, size)) {
+		printk(KERN_INFO "nand_ecc-test: ok - %s\n", testname);
+		return 0;
+	}
+
+	printk(KERN_ERR "nand_ecc-test: not ok - %s\n", testname);
+
+	printk(KERN_DEBUG "hexdump of data:\n");
+	print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 16, 4,
+			data, size, false);
+	printk(KERN_DEBUG "hexdump of error data:\n");
+	print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 16, 4,
+			error_data, size, false);
+
+	return -1;
+}
+
+#else
+
+static int nand_ecc_test(const size_t size)
+{
+	return 0;
+}
+
+#endif
+
+static int __init ecc_test_init(void)
+{
+	srandom32(jiffies);
+
+	nand_ecc_test(256);
+	nand_ecc_test(512);
+
+	return 0;
+}
+
+static void __exit ecc_test_exit(void)
+{
+}
+
+module_init(ecc_test_init);
+module_exit(ecc_test_exit);
+
+MODULE_DESCRIPTION("ECC test module");
+MODULE_AUTHOR("Akinobu Mita");
+MODULE_LICENSE("GPL");