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

Sekhar Nori nsekhar at ti.com
Thu Aug 8 12:05:37 EDT 2013


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,
Sekhar



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