Re: [PATCH net-next 2/2] net: ipa: add IPA v4.7 support

From: Alex Elder <elder@linaro.org>
To: Konrad Dybcio <konrad.dybcio@linaro.org>,
	Alex Elder <elder@linaro.org>,
	davem@davemloft.net, edumazet@google.com, kuba@kernel.org,
	pabeni@redhat.com
Cc: andersson@kernel.org, agross@kernel.org, robh+dt@kernel.org,
	krzysztof.kozlowski+dt@linaro.org, elder@kernel.org,
	linux-arm-msm@vger.kernel.org, netdev@vger.kernel.org,
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
	Luca Weiss <luca.weiss@fairphone.com>
Subject: Re: [PATCH net-next 2/2] net: ipa: add IPA v4.7 support
Date: Fri, 9 Dec 2022 14:22:39 -0600	[thread overview]
Message-ID: <fa6d342e-0cfe-b870-b044-b0af476e3905@linaro.org> (raw)
In-Reply-To: <47b2fb29-1c2e-db6e-b14f-6dfe90341825@linaro.org>

On 12/8/22 3:22 PM, Konrad Dybcio wrote:
> 
> 
> On 8.12.2022 22:15, Alex Elder wrote:
>> Add the necessary register and data definitions needed for IPA v4.7,
>> which is found on the SM6350 SoC.
>>
>> Co-developed-by: Luca Weiss <luca.weiss@fairphone.com>
>> Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
>> Signed-off-by: Alex Elder <elder@linaro.org>
>> ---
> [...]
>> +
>> +/* Memory configuration data for an SoC having IPA v4.7 */
>> +static const struct ipa_mem_data ipa_mem_data = {
>> +	.local_count	= ARRAY_SIZE(ipa_mem_local_data),
>> +	.local		= ipa_mem_local_data,
>> +	.imem_addr	= 0x146a9000,
>> +	.imem_size	= 0x00002000,
> Should probably be
> 
> 0x146a8000
> 0x00003000
> 
> with an appropriate change in dt to reserve that region.
> 
> Qualcomm does:
> ipa@... { qcom,additional-mapping = <0x146a8000 0x146a8000 0x2000>; };
> 
> which covers 0x146a8000-0x146a9fff
> 
> plus
> 
> imem@.. { reg = <0x146aa000 0x1000>; };
> 
> which in total gives us 0x146a8000-0x146aafff

Can you tell me where you found this information?

> That would also mean all of your writes are kind of skewed, unless
> you already applied some offsets to them.

This region is used by the modem, but must be set up
by the AP.

> (IMEM on 6350 starts at 0x14680000 and is 0x2e000 long, as per
> the bootloader memory map)

On SM7250 (sorry, I don't know about 7225, or 6350 for that matter),
the IMEM starts at 0x14680000 and has length 0x2c000.  However that
memory is used by multiple entities.  The portion set aside for IPA
starts at 0x146a9000 and has size 0x2000.

					-Alex

> Konrad