From mboxrd@z Thu Jan  1 00:00:00 1970
From: Guenter Roeck <linux@roeck-us.net>
Subject: Re: [PATCH -next] net: hisilicon: Never build on SPARC
Date: Wed, 21 Oct 2015 10:03:05 -0700
Message-ID: <5627C549.9080600@roeck-us.net>
References: <1445437773-23261-1-git-send-email-linux@roeck-us.net>
 <5627A792.3020201@roeck-us.net>
 <20151021.083311.2193871332944250588.davem@davemloft.net>
 <4129407.LpDXnpSZOL@wuerfel>
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Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org
To: Arnd Bergmann <arnd@arndb.de>, David Miller <davem@davemloft.net>
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On 10/21/2015 08:57 AM, Arnd Bergmann wrote:
> On Wednesday 21 October 2015 08:33:11 David Miller wrote:
>> From: Guenter Roeck <linux@roeck-us.net>
>> Date: Wed, 21 Oct 2015 07:56:18 -0700
>>
>>>> @@ -57,6 +57,11 @@ extern int of_dma_get_range(struct device_node *np,
>>>> u64 *dma_addr,
>>>>                               u64 *paddr, u64 *size);
>>>>    extern bool of_dma_is_coherent(struct device_node *np);
>>>>    #else /* CONFIG_OF_ADDRESS */
>>>> +static inline u64 of_translate_address(struct device_node *np, const
>>>> __be32 *addr)
>>>> +{
>>>> +    return 0;
>>>
>>> Maybe return OF_BAD_ADDR ?
>>
>> The thing to really do on sparc, is just return the address raw untranslated
>> because that just works.
>>
>
> We still need to check #address-cells, right?
>
> Something like this?
>
> static inline u64 of_translate_address(struct device_node *np, const __be32 *addr)
> {
> #if defined(CONFIG_SPARC) || defined(CONFIG_M68K)
> 	int pna = of_n_addr_cells(np);
> 	u64 ret = be32_to_cpu(addr[pna - 1]);
>
> 	if (pna > 1)
> 		ret += (u64)be32_to_cpu(addr[pna - 2]) << 32;
>
> 	return ret;

That suggests that sparc would need a translation after all, which
seems to contradict what David said earlier.

Anyway, if it gets that complicated, I think we should stick with
just returning OF_BAD_ADDR. The above really suggests the need for
an architecture specific solution.

Guenter

> #else
> 	return OF_BAD_ADDR;
> #endif
> }
>
> 	Arnd
>