[PATCH v3 6/6] ARM: davinci: da850: configure system configuration chip(CFGCHIP3) for emac

Prabhakar Lad prabhakar.csengg at gmail.com
Thu Aug 8 06:39:50 EDT 2013


On Thu, Aug 8, 2013 at 9:35 PM, Sekhar Nori <nsekhar at ti.com> wrote:
> On Thursday 08 August 2013 04:02 PM, Prabhakar Lad wrote:
>> Hi Sekhar,
>>
>> Sorry for the  delayed response I was on leave and now back again up
>> and running.
>>
>> On Wed, Jul 31, 2013 at 11:17 AM, Sekhar Nori <nsekhar at ti.com> wrote:
>>> On Sunday 23 June 2013 08:30 PM, Prabhakar Lad wrote:
>>>> From: "Lad, Prabhakar" <prabhakar.csengg at gmail.com>
>>>>
>>>> This patch makes a common function for to configure emac and calls
>>>> it appropriately in DT and non DT boot mode. The system configuration
>>>> chip CFGCHIP3, controls the emac module. This patch appropriately
>>>> configures this register for emac and sets DA850_MII_MDIO_CLKEN_PIN
>>>> GPIO pin appropriately.
>>>>
>> [Snip]
>>
>>>> +     if (rmii_enabled)
>>>> +             val |= BIT(8);
>>>> +     else
>>>> +             val &= ~BIT(8);
>>>> +
>>>> +     /* configure the CFGCHIP3 register for RMII or MII */
>>>> +     writel(val, cfg_chip3_base);
>>>> +
>>>> +     ret = davinci_cfg_reg(DA850_GPIO2_6);
>>>> +     if (ret)
>>>> +             pr_warn("%s:GPIO(2,6) mux setup failed\n", __func__);
>>>> +
>>>> +     ret = gpio_request(DA850_MII_MDIO_CLKEN_PIN, "mdio_clk_en");
>>>> +     if (ret) {
>>>> +             pr_warn("Cannot open GPIO %d\n", DA850_MII_MDIO_CLKEN_PIN);
>>>> +             return;
>>>> +     }
>>>
>>> You cannot do this in SoC specific code. All boards wont use a GPIO to
>>> choose between MII/RMII. You need to do this in a EVM specific manner.
>>> This just means you retain the GPIO part of code in board-da850-evm.c
>>
>> OK
>>
>>> and for the DT case use a board specific GPIO node. See a similar
>>> example in arch/arm/boot/dts/ste-nomadik-s8815.dts and how the code uses
>> Alrite something similar to usb-s8815 node.
>>
>>> it in arch/arm/mach-nomadik/cpu-8815.c.
>>>
>> But I don't see any code to access this node in this file, can
>> you point me to right direction ?
>
> Look at cpu8815_eth_init() function in this file.
>
Thanks, I was looking at some earlier version of code here [1],
where this was missing.

[1] https://github.com/AndrewDB/rk3066-kernel/blob/master/arch/arm/mach-nomadik/cpu-8815.c

Regards,
--Prabhakar Lad



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