[U-Boot] bug when using environment in an i2c eeprom and SPI is enabled?

[U-Boot] bug when using environment in an i2c eeprom and SPI is enabled?

[Heiko Schocher]

Hello Wolfgang,

I actually try to use Environment on an I2C EEprom with SPI enabled,
and found in include/common.h the following defines @line 326ff:

/*
 * Set this up regardless of board
 * type, to prevent errors.
 */
#if defined(CONFIG_SPI) || !defined(CONFIG_SYS_I2C_EEPROM_ADDR)
# define CONFIG_SYS_DEF_EEPROM_ADDR 0
#else
# define CONFIG_SYS_DEF_EEPROM_ADDR CONFIG_SYS_I2C_EEPROM_ADDR
#endif /* CONFIG_SPI || !defined(CONFIG_SYS_I2C_EEPROM_ADDR) */

So, it seems to me, that, if SPI is enabled, it is not possible
to use an I2C EEprom with an address != 0, because in
common/env_eeprom.c @line79 in env_init():

       /* read old CRC */a
        eeprom_read (CONFIG_SYS_DEF_EEPROM_ADDR,
                     CONFIG_ENV_OFFSET+offsetof(env_t,crc),
                     (uchar *)&crc, sizeof(ulong));

CONFIG_SYS_DEF_EEPROM_ADDR is fix used ...

I tried to use "git blame" to find out where this comes from,
but this is in code since the "initial revision" ... so I ask
here on the mailinglist, if somebody knows, if this is a
feature or a bug?

BTW, I think it should be:

diff --git a/include/common.h b/include/common.h
index 9e4b859..411563b 100644
--- a/include/common.h
+++ b/include/common.h
@@ -327,7 +327,7 @@ extern void  pic_write (uchar reg, uchar val);
  * Set this up regardless of board
  * type, to prevent errors.
  */
-#if defined(CONFIG_SPI) || !defined(CONFIG_SYS_I2C_EEPROM_ADDR)
+#if defined(CONFIG_SPI) && !defined(CONFIG_SYS_I2C_EEPROM_ADDR)
 # define CONFIG_SYS_DEF_EEPROM_ADDR 0
 #else
 # define CONFIG_SYS_DEF_EEPROM_ADDR CONFIG_SYS_I2C_EEPROM_ADDR

What do you think?

thanks
Heiko
-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany

[U-Boot] bug when using environment in an i2c eeprom and SPI is enabled?

[Wolfgang Denk]

Dear Heiko Schocher,

In message <4A5ED846.90305@denx.de> you wrote:
> 
> I actually try to use Environment on an I2C EEprom with SPI enabled,
> and found in include/common.h the following defines @line 326ff:

I'm not surprised...

> So, it seems to me, that, if SPI is enabled, it is not possible
> to use an I2C EEprom with an address != 0, because in
> common/env_eeprom.c @line79 in env_init():

Actually you are most probably not supposed to use any I2C EEPROM at
all.

> I tried to use "git blame" to find out where this comes from,
> but this is in code since the "initial revision" ... so I ask
> here on the mailinglist, if somebody knows, if this is a
> feature or a bug?

I think this is a deficiency of  the  original  implementation  which
assumed  that  if  there was an EEPROM, it was either attached to the
I2C or to the SPI bus, and that SPI would never be used in U-Boot for
anything else than reading an EEPROM.

Please consider it a bug...

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
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