[U-Boot] [PATCH v2 2/2] Add a cli command to test the TPM device.

[U-Boot] [PATCH v2 2/2] Add a cli command to test the TPM device.

[Vadim Bendebury]

The command gets an arbitrary number of arguments (up to 30), which
are interpreted as byte values and are feed into the TPM device after
proper initialization. Then the return value and data of the TPM
driver is examined.

TPM commands are described in the TCG specification.

For instance, the following sequence is the 'TPM Startup' command, it
is processed by the TPM and a response is generated:

boot > tpm 0x0 0xc1 0x0 0x0 0x0 0xc 0x0 0x0 0x0 0x99 0x0 0x1
Found TPM SLB9635 TT 1.2 by Infineon
Got TPM response:
 00 c4 00 00 00 0a 00 00 00 00

If the command is corrupted (fed one byte short), an error is reported:
boot > tpm 0x0 0xc1 0x0 0x0 0x0 0xc 0x0 0x0 0x0 0x99 0x0
generic_lpc_tpm.c:311 unexpected TPM status 0xff000888
generic_lpc_tpm.c:516 failed sending data to TPM
tpm command failed
boot >

Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
CC: Wolfgang Denk <wd@denx.de>
---
 common/Makefile  |    2 +
 common/cmd_tpm.c |  111 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 113 insertions(+), 0 deletions(-)
 create mode 100644 common/cmd_tpm.c

diff --git a/common/Makefile b/common/Makefile
index 371a0d9..28c2ec5 100644
--- a/common/Makefile
+++ b/common/Makefile
@@ -153,6 +153,8 @@ COBJS-$(CONFIG_CMD_UBI) += cmd_ubi.o
 COBJS-$(CONFIG_CMD_UBIFS) += cmd_ubifs.o
 COBJS-$(CONFIG_CMD_UNIVERSE) += cmd_universe.o
 COBJS-$(CONFIG_CMD_UNZIP) += cmd_unzip.o
+COBJS-$(CONFIG_CMD_TPM) += cmd_tpm.o
+
 ifdef CONFIG_CMD_USB
 COBJS-y += cmd_usb.o
 COBJS-y += usb.o
diff --git a/common/cmd_tpm.c b/common/cmd_tpm.c
new file mode 100644
index 0000000..e008a78
--- /dev/null
+++ b/common/cmd_tpm.c
@@ -0,0 +1,111 @@
+/*
+ * Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
+ * Released under the 2-clause BSD license.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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
+ */
+
+#include <common.h>
+#include <command.h>
+#include <tpm.h>
+
+#define MAX_TRANSACTION_SIZE 30
+static void report_error(const char *msg);
+
+/*
+ * tpm_write() expects a variable number of parameters: the internal address
+ * followed by data to write, byte by byte.
+ *
+ * Returns 0 on success or ~0 on errors (wrong arguments or TPM failure).
+ */
+static int tpm_process(int argc, char * const argv[])
+{
+	u8 tpm_buffer[MAX_TRANSACTION_SIZE];
+	u32 write_size, read_size;
+	char *p;
+	int rv = ~0;
+
+	for (write_size = 0; write_size < argc; write_size++) {
+		u32 datum = simple_strtoul(argv[write_size], &p, 0);
+		if (*p || (datum > 0xff)) {
+			printf("%s: ", argv[write_size]);
+			report_error("bad data value\n");
+			return rv;
+		}
+		tpm_buffer[write_size] = (u8)datum;
+	}
+
+	read_size = sizeof(tpm_buffer);
+	if (!tis_sendrecv(tpm_buffer, write_size, tpm_buffer, &read_size)) {
+		int i;
+		puts("Got TPM response:\n");
+		for (i = 0; i < read_size; i++)
+			printf(" %2.2x", tpm_buffer[i]);
+		puts("\n");
+		rv = 0;
+	} else {
+		puts("tpm command failed\n");
+	}
+	return rv;
+}
+
+static int do_tpm(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+	int rv = 0;
+
+	/*
+	 * Verify that in case it is present, the first argument, it is
+	 * exactly one character in size.
+	 */
+	if (argc < 7) {
+		puts("command should be@least six bytes in size\n");
+		return ~0;
+	}
+
+	if (tis_init()) {
+		puts("tis_init() failed!\n");
+		return ~0;
+	}
+
+	if (tis_open()) {
+		puts("tis_open() failed!\n");
+		return ~0;
+	}
+
+	rv = tpm_process(argc - 1, argv + 1);
+
+	if (!rv && tis_close()) {
+		puts("tis_close() failed!\n");
+		rv = ~0;
+	}
+
+	return rv;
+}
+
+U_BOOT_CMD(tpm, MAX_TRANSACTION_SIZE, 1, do_tpm,
+	   "tpm <data> [<data>]   - write data and read ressponse\n",
+	   "send arbitrary data to the TPM and read the response"
+);
+
+static void report_error(const char *msg)
+{
+	if (msg && *msg)
+		printf("%s\n", msg);
+	cmd_usage(&__u_boot_cmd_tpm);
+}
-- 
1.7.3.1

[U-Boot] [PATCH v2 2/2] Add a cli command to test the TPM device.

[Marek Vasut]

On Saturday, October 15, 2011 05:39:08 AM Vadim Bendebury wrote:
> The command gets an arbitrary number of arguments (up to 30), which
> are interpreted as byte values and are feed into the TPM device after
> proper initialization. Then the return value and data of the TPM
> driver is examined.
> 

Dear Vadim Bendebury,

[...]

> diff --git a/common/cmd_tpm.c b/common/cmd_tpm.c
> new file mode 100644
> index 0000000..e008a78
> --- /dev/null
> +++ b/common/cmd_tpm.c
> @@ -0,0 +1,111 @@
> +/*
> + * Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
> + * Released under the 2-clause BSD license.

Are we ok with this ? Also, you say something about GPL in the same comment?

> + *
> + * See file CREDITS for list of people who contributed to this
> + * project.
> + *
> + * 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
> + */
> +

[...]

> +		puts("Got TPM response:\n");
> +		for (i = 0; i < read_size; i++)
> +			printf(" %2.2x", tpm_buffer[i]);
> +		puts("\n");
> +		rv = 0;
> +	} else {
> +		puts("tpm command failed\n");
> +	}
> +	return rv;
> +}

You might want to use debug() where fitting ?

> +
> +static int do_tpm(cmd_tbl_t *cmdtp, int flag, int argc, char * const
> argv[]) +{
> +	int rv = 0;
> +
> +	/*
> +	 * Verify that in case it is present, the first argument, it is
> +	 * exactly one character in size.
> +	 */
> +	if (argc < 7) {
> +		puts("command should be at least six bytes in size\n");
> +		return ~0;

Ugh, return 1 isn't ok ? Using ~0 on int type is weird.

> +	}
> +
> +	if (tis_init()) {
> +		puts("tis_init() failed!\n");
> +		return ~0;
> +	}
> +
> +	if (tis_open()) {
> +		puts("tis_open() failed!\n");
> +		return ~0;
> +	}
> +
> +	rv = tpm_process(argc - 1, argv + 1);
> +
> +	if (!rv && tis_close()) {
> +		puts("tis_close() failed!\n");
> +		rv = ~0;

This doesn't make much sense, tis_close() might not be called under all 
circumstances, is it ok ?

> +	}
> +
> +	return rv;
> +}
> +
> +U_BOOT_CMD(tpm, MAX_TRANSACTION_SIZE, 1, do_tpm,
> +	   "tpm <data> [<data>]   - write data and read ressponse\n",
> +	   "send arbitrary data to the TPM and read the response"
> +);
> +
> +static void report_error(const char *msg)
> +{
> +	if (msg && *msg)

Uhm, you also check if first character is non-zero? why ?

> +		printf("%s\n", msg);
> +	cmd_usage(&__u_boot_cmd_tpm);

Two underscores aren't a good practice.

> +}

Cheers

[U-Boot] [PATCH v2 2/2] Add a cli command to test the TPM device.

[Vadim Bendebury]

Dear Marek Vasut,

thank you for your comments, please see below:

On Sat, Oct 15, 2011 at 11:02 AM, Marek Vasut <marek.vasut@gmail.com> wrote:
> On Saturday, October 15, 2011 05:39:08 AM Vadim Bendebury wrote:
>> The command gets an arbitrary number of arguments (up to 30), which
>> are interpreted as byte values and are feed into the TPM device after
>> proper initialization. Then the return value and data of the TPM
>> driver is examined.
>>
>
> Dear Vadim Bendebury,
>
> [...]
>
>> diff --git a/common/cmd_tpm.c b/common/cmd_tpm.c
>> new file mode 100644
>> index 0000000..e008a78
>> --- /dev/null
>> +++ b/common/cmd_tpm.c
>> @@ -0,0 +1,111 @@
>> +/*
>> + * Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
>> + * Released under the 2-clause BSD license.
>
> Are we ok with this ? Also, you say something about GPL in the same comment?
>

Can someone please tell me what needs to be put in the license headers
and I will do it. I hear different suggestions from different people.

>> + *
>> + * See file CREDITS for list of people who contributed to this
>> + * project.
>> + *
>> + * 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
>> + */
>> +
>
> [...]
>
>> + ? ? ? ? ? ? puts("Got TPM response:\n");
>> + ? ? ? ? ? ? for (i = 0; i < read_size; i++)
>> + ? ? ? ? ? ? ? ? ? ? printf(" %2.2x", tpm_buffer[i]);
>> + ? ? ? ? ? ? puts("\n");
>> + ? ? ? ? ? ? rv = 0;
>> + ? ? } else {
>> + ? ? ? ? ? ? puts("tpm command failed\n");
>> + ? ? }
>> + ? ? return rv;
>> +}
>
> You might want to use debug() where fitting ?
>

I don't expect failures and if happen prefer them to be printed
always, not only if debug is enabled.

>> +
>> +static int do_tpm(cmd_tbl_t *cmdtp, int flag, int argc, char * const
>> argv[]) +{
>> + ? ? int rv = 0;
>> +
>> + ? ? /*
>> + ? ? ?* Verify that in case it is present, the first argument, it is
>> + ? ? ?* exactly one character in size.
>> + ? ? ?*/
>> + ? ? if (argc < 7) {
>> + ? ? ? ? ? ? puts("command should be at least six bytes in size\n");
>> + ? ? ? ? ? ? return ~0;
>
> Ugh, return 1 isn't ok ? Using ~0 on int type is weird.
>

I was under impression that any nonzero value is good. I see sometimes
-1 returned for error in other u-boot sources. Also, I am sorry, I am
new to this, when someone says "it is weird" - does this mean that  it
has to be changed?

>> + ? ? }
>> +
>> + ? ? if (tis_init()) {
>> + ? ? ? ? ? ? puts("tis_init() failed!\n");
>> + ? ? ? ? ? ? return ~0;
>> + ? ? }
>> +
>> + ? ? if (tis_open()) {
>> + ? ? ? ? ? ? puts("tis_open() failed!\n");
>> + ? ? ? ? ? ? return ~0;
>> + ? ? }
>> +
>> + ? ? rv = tpm_process(argc - 1, argv + 1);
>> +
>> + ? ? if (!rv && tis_close()) {
>> + ? ? ? ? ? ? puts("tis_close() failed!\n");
>> + ? ? ? ? ? ? rv = ~0;
>
> This doesn't make much sense, tis_close() might not be called under all
> circumstances, is it ok ?
>

good point, I thought about this, but left untouched. It does not
matter with this driver, but is better to call tis_close() no matter
what. I'll fix it.

>> + ? ? }
>> +
>> + ? ? return rv;
>> +}
>> +
>> +U_BOOT_CMD(tpm, MAX_TRANSACTION_SIZE, 1, do_tpm,
>> + ? ? ? ?"tpm <data> [<data>] ? - write data and read ressponse\n",
>> + ? ? ? ?"send arbitrary data to the TPM and read the response"
>> +);
>> +
>> +static void report_error(const char *msg)
>> +{
>> + ? ? if (msg && *msg)
>
> Uhm, you also check if first character is non-zero? why ?

To avoid printing an empty string if someone calls this with an empty message?

>
>> + ? ? ? ? ? ? printf("%s\n", msg);
>> + ? ? cmd_usage(&__u_boot_cmd_tpm);
>
> Two underscores aren't a good practice.
>

I did this as a result of a previous review. Do you have a suggestion
how this should be done instead?

cheers,
/vb

>> +}
>
> Cheers
>

[U-Boot] [PATCH v2 2/2] Add a cli command to test the TPM device.

[Mike Frysinger]

On Saturday 15 October 2011 14:02:29 Marek Vasut wrote:
> On Saturday, October 15, 2011 05:39:08 AM Vadim Bendebury wrote:
> > --- /dev/null
> > +++ b/common/cmd_tpm.c
> > @@ -0,0 +1,111 @@
> > +/*
> > + * Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
> > + * Released under the 2-clause BSD license.
> 
> Are we ok with this ? Also, you say something about GPL in the same
> comment?

there's nothing wrong with adding files under the BSD license.  what is odd 
about this code though is that it says BSD on one line, and then it says 
GPL-2+ a few lines later.  pick one or the other.

> > +	/*
> > +	 * Verify that in case it is present, the first argument, it is
> > +	 * exactly one character in size.
> > +	 */
> > +	if (argc < 7) {
> > +		puts("command should be at least six bytes in size\n");
> > +		return ~0;
> 
> Ugh, return 1 isn't ok ? Using ~0 on int type is weird.

~0 is weird.  this should be 1 or -1.
-mike
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[U-Boot] [PATCH v2 2/2] Add a cli command to test the TPM device.

[Mike Frysinger]

On Friday 14 October 2011 23:39:08 Vadim Bendebury wrote:
> --- /dev/null
> +++ b/common/cmd_tpm.c
>
> +	/*
> +	 * Verify that in case it is present, the first argument, it is
> +	 * exactly one character in size.
> +	 */
> +	if (argc < 7) {
> +		puts("command should be at least six bytes in size\n");
> +		return ~0;
> +	}
> ...
> +U_BOOT_CMD(tpm, MAX_TRANSACTION_SIZE, 1, do_tpm,
> +	   "tpm <data> [<data>]   - write data and read ressponse\n",

the usage information does not convey that you have to do:
	tpm 1 2 3 4 5 6 7 8 9
perhaps says "<byte> [<byte> ...]" instead ?  and note that you have to 
specify at least 6 ?

also, there's a typo: ressponse -> response

> +static void report_error(const char *msg)
> +{
> +	if (msg && *msg)
> +		printf("%s\n", msg);
> +	cmd_usage(&__u_boot_cmd_tpm);
> +}

this gets used in one place, and the one place where it does get used, i don't 
see a point in calling cmd_usage().  just have the one place where this is 
used call puts() instead.
-mike
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[U-Boot] [PATCH v2 2/2] Add a cli command to test the TPM device.

[Mike Frysinger]

On Friday 14 October 2011 23:39:08 Vadim Bendebury wrote:
> --- a/common/Makefile
> +++ b/common/Makefile
>
>  COBJS-$(CONFIG_CMD_UBIFS) += cmd_ubifs.o
>  COBJS-$(CONFIG_CMD_UNIVERSE) += cmd_universe.o
>  COBJS-$(CONFIG_CMD_UNZIP) += cmd_unzip.o
> +COBJS-$(CONFIG_CMD_TPM) += cmd_tpm.o

keep the list sorted
-mike
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[U-Boot] [PATCH v2 2/2] Add a cli command to test the TPM device.

[Wolfgang Denk]

Dear Vadim Bendebury,

In message <CAC3GErHaAGX39XjD04MnJWe3sa9XC087LLpf6SycVC6K7SLt6Q@mail.gmail.com> you wrote:
> 
> >> + * Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
> >> + * Released under the 2-clause BSD license.
> >
> > Are we ok with this ? Also, you say something about GPL in the same comment?
> >
>
> Can someone please tell me what needs to be put in the license headers
> and I will do it. I hear different suggestions from different people.

See previous comment - drop the BSD part if you include a GPLv2+
license header.

> >> +             return ~0;
> >
> > Ugh, return 1 isn't ok ? Using ~0 on int type is weird.
>
> I was under impression that any nonzero value is good. I see sometimes
> -1 returned for error in other u-boot sources. Also, I am sorry, I am
> new to this, when someone says "it is weird" - does this mean that  it
> has to be changed?

Commands are running in some sort of shell environment.  SO please
return 0 for OK and 1 for general errors like all other commands do
(or should do).

...
> >> +static void report_error(const char *msg)
> >> +{
> >> +   if (msg && *msg)
> >
> > Uhm, you also check if first character is non-zero? why ?
>
> To avoid printing an empty string if someone calls this with an empty message?

It's your code, so just don't do it, then.

And what's wrong about printing an empty string?  YOuy're just adding
dead code (and increased memory footprint) here.

> > Two underscores aren't a good practice.
>
> I did this as a result of a previous review. Do you have a suggestion
> how this should be done instead?

First, and most important, __u_boot_cmd_tpm appears to be undefined in
your two patches, so it looks to be a real bug.

Second, please read the C standard's section about reserved
identifiers.

Best regards,

Wolfgang Denk

-- 
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HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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Friday night was a comfortably long way off.
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[U-Boot] [PATCH v2 2/2] Add a cli command to test the TPM device.

[Mike Frysinger]

On Saturday 15 October 2011 15:44:04 Wolfgang Denk wrote:
> Vadim Bendebury wrote:
> > > Two underscores aren't a good practice.
> > 
> > I did this as a result of a previous review. Do you have a suggestion
> > how this should be done instead?
> 
> First, and most important, __u_boot_cmd_tpm appears to be undefined in
> your two patches, so it looks to be a real bug.
> 
> Second, please read the C standard's section about reserved
> identifiers.

no, this is coming from common u-boot code.  look at 
include/command.h:U_BOOT_CMD defines.
-mike
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[U-Boot] [PATCH v2 2/2] Add a cli command to test the TPM device.

[Vadim Bendebury]

On Sat, Oct 15, 2011 at 1:01 PM, Mike Frysinger <vapier@gentoo.org> wrote:
> On Saturday 15 October 2011 15:44:04 Wolfgang Denk wrote:
>> Vadim Bendebury wrote:
>> > > Two underscores aren't a good practice.
>> >
>> > I did this as a result of a previous review. Do you have a suggestion
>> > how this should be done instead?
>>
>> First, and most important, __u_boot_cmd_tpm appears to be undefined in
>> your two patches, so it looks to be a real bug.
>>
>> Second, please read the C standard's section about reserved
>> identifiers.
>
> no, this is coming from common u-boot code. ?look at
> include/command.h:U_BOOT_CMD defines.
> -mike
>

or, more importantly: the question is what is the right/suggested way
to print out the help message associated with a U_BOOT_CMD
declaration?

cheers,
/vb

[U-Boot] [PATCH v2 2/2] Add a cli command to test the TPM device.

[Vadim Bendebury]

On Sat, Oct 15, 2011 at 12:08 PM, Mike Frysinger <vapier@gentoo.org> wrote:
> On Saturday 15 October 2011 14:02:29 Marek Vasut wrote:
>> On Saturday, October 15, 2011 05:39:08 AM Vadim Bendebury wrote:
>> > --- /dev/null
>> > +++ b/common/cmd_tpm.c
>> > @@ -0,0 +1,111 @@
>> > +/*
>> > + * Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
>> > + * Released under the 2-clause BSD license.
>>
>> Are we ok with this ? Also, you say something about GPL in the same
>> comment?
>
> there's nothing wrong with adding files under the BSD license. ?what is odd
> about this code though is that it says BSD on one line, and then it says
> GPL-2+ a few lines later. ?pick one or the other.
>
done

>> > + ? /*
>> > + ? ?* Verify that in case it is present, the first argument, it is
>> > + ? ?* exactly one character in size.
>> > + ? ?*/
>> > + ? if (argc < 7) {
>> > + ? ? ? ? ? puts("command should be at least six bytes in size\n");
>> > + ? ? ? ? ? return ~0;
>>
>> Ugh, return 1 isn't ok ? Using ~0 on int type is weird.
>
> ~0 is weird. ?this should be 1 or -1.

done

> -mike
>

[U-Boot] [PATCH v2 2/2] Add a cli command to test the TPM device.

[Vadim Bendebury]

Dear Wolfgang Denk,

On Sat, Oct 15, 2011 at 12:44 PM, Wolfgang Denk <wd@denx.de> wrote:
> Dear Vadim Bendebury,
>
> In message <CAC3GErHaAGX39XjD04MnJWe3sa9XC087LLpf6SycVC6K7SLt6Q@mail.gmail.com> you wrote:
>>
>> >> + * Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
>> >> + * Released under the 2-clause BSD license.
>> >
>> > Are we ok with this ? Also, you say something about GPL in the same comment?
>> >
>>
>> Can someone please tell me what needs to be put in the license headers
>> and I will do it. I hear different suggestions from different people.
>
> See previous comment - drop the BSD part if you include a GPLv2+
> license header.
>

done

>> >> + ? ? ? ? ? ? return ~0;
>> >
>> > Ugh, return 1 isn't ok ? Using ~0 on int type is weird.
>>
>> I was under impression that any nonzero value is good. I see sometimes
>> -1 returned for error in other u-boot sources. Also, I am sorry, I am
>> new to this, when someone says "it is weird" - does this mean that ?it
>> has to be changed?
>
> Commands are running in some sort of shell environment. ?SO please
> return 0 for OK and 1 for general errors like all other commands do
> (or should do).
>

done

> ...
>> >> +static void report_error(const char *msg)
>> >> +{
>> >> + ? if (msg && *msg)
>> >
>> > Uhm, you also check if first character is non-zero? why ?
>>
>> To avoid printing an empty string if someone calls this with an empty message?
>
> It's your code, so just don't do it, then.
>
> And what's wrong about printing an empty string? ?YOuy're just adding
> dead code (and increased memory footprint) here.
>
>> > Two underscores aren't a good practice.
>>
>> I did this as a result of a previous review. Do you have a suggestion
>> how this should be done instead?
>
> First, and most important, __u_boot_cmd_tpm appears to be undefined in
> your two patches, so it looks to be a real bug.
>
> Second, please read the C standard's section about reserved
> identifiers.
>


reworked to avoid all the complications.

cheers,
/vb

> Best regards,
>
> Wolfgang Denk
>
> --
> DENX Software Engineering GmbH, ? ? MD: Wolfgang Denk & Detlev Zundel
> HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
> Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
> The universe contains any amount of horrible ways ?to ?be ?woken ?up,
> such as the noise of the mob breaking down the front door, the scream
> of fire engines, or the realization that today is the Monday which on
> Friday night was a comfortably long way off.
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? - Terry Pratchett, _Moving Pictures_
>

[U-Boot] [PATCH v2 2/2] Add a cli command to test the TPM device.

[Mike Frysinger]

On Saturday 15 October 2011 16:27:02 Vadim Bendebury wrote:
> On Sat, Oct 15, 2011 at 1:01 PM, Mike Frysinger <vapier@gentoo.org> wrote:
> > On Saturday 15 October 2011 15:44:04 Wolfgang Denk wrote:
> >> Vadim Bendebury wrote:
> >> > > Two underscores aren't a good practice.
> >> > 
> >> > I did this as a result of a previous review. Do you have a suggestion
> >> > how this should be done instead?
> >> 
> >> First, and most important, __u_boot_cmd_tpm appears to be undefined in
> >> your two patches, so it looks to be a real bug.
> >> 
> >> Second, please read the C standard's section about reserved
> >> identifiers.
> > 
> > no, this is coming from common u-boot code.  look at
> > include/command.h:U_BOOT_CMD defines.
> 
> or, more importantly: the question is what is the right/suggested way
> to print out the help message associated with a U_BOOT_CMD
> declaration?

your command is given a cmd_tbl_t *cmdtp pointer to pass to cmd_usage
-mike
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