[U-Boot] [PATCH v2 2/5] sunxi: net: Allow the sunxi to set the MAC from an EEPROM

[Olliver Schinagl <o.schinagl@ultimaker.com>]

Hey Joe

On 26-01-16 01:32, Joe Hershberger wrote:
> On Mon, Dec 14, 2015 at 6:41 AM, Olliver Schinagl
> <o.schinagl@ultimaker.com> wrote:
>> This patch uses the newly introduced Kconfig options to set the MAC
>> address from an EEPROM, this will be especially useful for the Olimex
>> OLinuXino series of sunxi boards as they all have an 2k i2c eeprom chip.
>>
>> The MAC address is in the eeprom is ignored if there is already a MAC
> "The MAC address in the eeprom is ignored..."
oops :) fixed for v3
>
>> address in the environment or (if enabled) the CRC8 check fails.
>>
>> Signed-off-by: Olliver Schinagl <o.schinagl@ultimaker.com>
>> ---
>>   board/sunxi/Kconfig |  4 ++++
>>   board/sunxi/board.c | 36 ++++++++++++++++++++++++++++++++++++
>>   net/Kconfig         |  1 +
>>   3 files changed, 41 insertions(+)
>>
>> diff --git a/board/sunxi/Kconfig b/board/sunxi/Kconfig
>> index 2dd9d3b..a2da3a6 100644
>> --- a/board/sunxi/Kconfig
>> +++ b/board/sunxi/Kconfig
>> @@ -339,18 +339,21 @@ config I2C0_ENABLE
>>
>>   config I2C1_ENABLE
>>          bool "Enable I2C/TWI controller 1"
>> +       default y if (NET_ETHADDR_EEPROM_I2C_BUS = 1)
>>          default n
>>          ---help---
>>          See I2C0_ENABLE help text.
>>
>>   config I2C2_ENABLE
>>          bool "Enable I2C/TWI controller 2"
>> +       default y if NET_ETHADDR_EEPROM_I2C_BUS = 2
>>          default n
>>          ---help---
>>          See I2C0_ENABLE help text.
>>
>>   if MACH_SUN6I || MACH_SUN7I
>>   config I2C3_ENABLE
>> +       default y if NET_ETHADDR_EEPROM_I2C_BUS = 3
>>          bool "Enable I2C/TWI controller 3"
>>          default n
>>          ---help---
>> @@ -359,6 +362,7 @@ endif
>>
>>   if MACH_SUN7I
>>   config I2C4_ENABLE
>> +       default y if NET_ETHADDR_EEPROM_I2C_BUS = 4
>>          bool "Enable I2C/TWI controller 4"
>>          default n
>>          ---help---
>> diff --git a/board/sunxi/board.c b/board/sunxi/board.c
>> index 6ac398c..28310a2 100644
>> --- a/board/sunxi/board.c
>> +++ b/board/sunxi/board.c
>> @@ -12,6 +12,7 @@
>>    */
>>
>>   #include <common.h>
>> +#include <i2c.h>
>>   #include <mmc.h>
>>   #include <axp_pmic.h>
>>   #include <asm/arch/clock.h>
>> @@ -23,6 +24,7 @@
>>   #include <asm/arch/usb_phy.h>
>>   #include <asm/gpio.h>
>>   #include <asm/io.h>
>> +#include <linux/crc8.h>
>>   #include <nand.h>
>>   #include <net.h>
>>
>> @@ -510,6 +512,37 @@ void get_board_serial(struct tag_serialnr *serialnr)
>>   }
>>   #endif
>>
>> +#if defined(CONFIG_NET_ETHADDR_EEPROM) && defined(CONFIG_NET_ETHADDR_EEPROM_I2C)
>> +static int read_mac_from_eeprom(uint8_t *mac_addr)
>> +{
>> +       uint8_t eeprom[7];
>> +       int old_i2c_bus;
>> +
>> +       old_i2c_bus = i2c_get_bus_num();
>> +       i2c_set_bus_num(CONFIG_NET_ETHADDR_EEPROM_I2C_BUS);
>> +       if (i2c_read(CONFIG_NET_ETHADDR_EEPROM_I2C_ADDR,
>> +                    CONFIG_NET_ETHADDR_EEPROM_OFFSET,
>> +                    CONFIG_NET_ETHADDR_EEPROM_I2C_ADDRLEN,
>> +                    eeprom, 7)) {
>> +               i2c_set_bus_num(old_i2c_bus);
>> +               puts("Could not read the EEPROM; EEPROM missing?\n");
>> +               return -1;
>> +       }
>> +       i2c_set_bus_num(old_i2c_bus);
>> +#ifdef CONFIG_NET_ETHADDR_EEPROM_CRC8
>> +       if (crc8(eeprom, 6) != eeprom[6]) {
>> +               puts("CRC error on MAC address from EEPROM.\n");
>> +               return -1;
>> +       }
>> +#endif
>> +       memcpy(mac_addr, eeprom, 6);
>> +
>> +       return 0;
>> +}
>> +#else
>> +static int read_mac_from_eeprom(uint8_t *mac_addr) { return -1; }
>> +#endif
>> +
>>   #if !defined(CONFIG_SPL_BUILD)
>>   #include <asm/arch/spl.h>
>>
>> @@ -553,6 +586,9 @@ int misc_init_r(void)
>>          }
>>   #endif
>>
>> +       if ((!getenv("ethaddr")) && (!read_mac_from_eeprom(mac_addr)))
>> +               eth_setenv_enetaddr("ethaddr", mac_addr);
> It seems a bit odd to actually write this to the environment instead
> of it being a read_rom_hwaddr operation for the Ethernet driver that
> this board uses.
>
> Do we need a different board-level ROM callback? Maybe the drivers
> used in such situations can be the only ones to support it.
I'm hoping your thinking out-loud, as I'm not too familiar with all the 
backing code. But if I understand you correctly, you suggest to 
implement a new callback for ethernet drivers to get mac's from eeprom? 
Anyhow, I just followed suit with how the address gets set in case of 
when it is not in the environment and we need to generate a random one.

I was reading the u-boot documentation and though the assumed method was 
to use the environment and to only use other methods (such as the eeprom 
method) where it is absolutely a must. In this case the eeprom is not 
directly related to the ethernet, it's a generic eeprom.

But then again, I am new to this stuff so I can be gladly very wrong here :)


>
>> +
>>          ret = sunxi_get_sid(sid);
>>          if (ret == 0 && sid[0] != 0 && sid[3] != 0) {
>>                  if (!getenv("ethaddr")) {
>> diff --git a/net/Kconfig b/net/Kconfig
>> index aced51e..0f4cc5a 100644
>> --- a/net/Kconfig
>> +++ b/net/Kconfig
>> @@ -8,6 +8,7 @@ menuconfig NET
>>   if NET
>>
>>   config NET_ETHADDR_EEPROM
>> +       depends on ARCH_SUNXI
>>          bool "Get ethaddr from eeprom"
>>          help
>>            Selecting this will try to get the Ethernet address from an onboard
>> --
>> 2.6.2
>>
>> _______________________________________________
>> U-Boot mailing list
>> U-Boot at lists.denx.de
>> http://lists.denx.de/mailman/listinfo/u-boot

-- 
Met vriendelijke groeten, Kind regards, ??????

Olliver Schinagl
Software Engineer
Research & Development
Ultimaker B.V.