Re: [PATCH V2 7/8] spi: spi-qcom-qspi: Add interconnect support

From: Akash Asthana <akashast@codeaurora.org>
To: Matthias Kaehlcke <mka@chromium.org>
Cc: gregkh@linuxfoundation.org, agross@kernel.org,
	bjorn.andersson@linaro.org, wsa@the-dreams.de,
	broonie@kernel.org, mark.rutland@arm.com, robh+dt@kernel.org,
	linux-i2c@vger.kernel.org, linux-spi@vger.kernel.org,
	devicetree@vger.kernel.org, swboyd@chromium.org,
	mgautam@codeaurora.org, linux-arm-msm@vger.kernel.org,
	linux-serial@vger.kernel.org, dianders@chromium.org,
	evgreen@chromium.org
Subject: Re: [PATCH V2 7/8] spi: spi-qcom-qspi: Add interconnect support
Date: Tue, 17 Mar 2020 17:43:01 +0530	[thread overview]
Message-ID: <3aeb3083-2a31-b269-510d-eb608ff14ce5@codeaurora.org> (raw)
In-Reply-To: <20200314005817.GN144492@google.com>

Hi Matthias,

On 3/14/2020 6:28 AM, Matthias Kaehlcke wrote:
> Hi,
>
> On Fri, Mar 13, 2020 at 06:42:13PM +0530, Akash Asthana wrote:
>> Get the interconnect paths for QSPI device and vote according to the
>> current bus speed of the driver.
>>
>> Signed-off-by: Akash Asthana <akashast@codeaurora.org>
>> ---
>>   - As per Bjorn's comment, introduced and using devm_of_icc_get API for getting
>>     path handle
>>   - As per Matthias comment, added error handling for icc_set_bw call
>>
>>   drivers/spi/spi-qcom-qspi.c | 46 ++++++++++++++++++++++++++++++++++++++++++++-
>>   1 file changed, 45 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/spi/spi-qcom-qspi.c b/drivers/spi/spi-qcom-qspi.c
>> index 3c4f83b..ad48f43 100644
>> --- a/drivers/spi/spi-qcom-qspi.c
>> +++ b/drivers/spi/spi-qcom-qspi.c
>> @@ -2,6 +2,7 @@
>>   // Copyright (c) 2017-2018, The Linux foundation. All rights reserved.
>>   
>>   #include <linux/clk.h>
>> +#include <linux/interconnect.h>
>>   #include <linux/interrupt.h>
>>   #include <linux/io.h>
>>   #include <linux/module.h>
>> @@ -139,7 +140,10 @@ struct qcom_qspi {
>>   	struct device *dev;
>>   	struct clk_bulk_data *clks;
>>   	struct qspi_xfer xfer;
>> -	/* Lock to protect xfer and IRQ accessed registers */
>> +	struct icc_path *icc_path_cpu_to_qspi;
>> +	unsigned int avg_bw_cpu;
>> +	unsigned int peak_bw_cpu;
> This triplet is a recurring pattern, and is probably not limited to geni SE/QSPI.
> On https://patchwork.kernel.org/patch/11436889/#23221925 I suggested the creation
> of a geni SE specific struct, however adding a generic convenience struct to
> 'linux/interconnect.h' might be the better solution:
>
> struct icc_client {
> 	struct icc_path *path;
> 	unsigned int avg_bw;
> 	unsigned int peak_bw;
> };
>
> I'm sure there are better names for it, but this would be the idea.

Yeah, I think introducing this to ICC header would be better solution.

Regards,

Akash

-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,\na Linux Foundation Collaborative Project