linux-kernel - Re: [V2] i2c: i2c-qcom-geni: Correct I2C TRE sequence

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <56f08eaf-079c-4076-b900-710884db6ca5@linaro.org>
Date: Tue, 30 Jan 2024 11:32:28 +0000
From: Bryan O'Donoghue <bryan.odonoghue@...aro.org>
To: Andi Shyti <andi.shyti@...nel.org>,
 Viken Dadhaniya <quic_vdadhani@...cinc.com>
Cc: andersson@...nel.org, konrad.dybcio@...aro.org,
 linux-arm-msm@...r.kernel.org, linux-i2c@...r.kernel.org,
 linux-kernel@...r.kernel.org, vkoul@...nel.org, quic_bjorande@...cinc.com,
 manivannan.sadhasivam@...aro.org, quic_msavaliy@...cinc.com,
 quic_vtanuku@...cinc.com
Subject: Re: [V2] i2c: i2c-qcom-geni: Correct I2C TRE sequence

On 29/01/2024 23:24, Andi Shyti wrote:
> Hi Viken,
> 
> as Bryan has done some comments in version 1, please, Cc him to
> this patch.
> 
> On Mon, Jan 29, 2024 at 11:40:03AM +0530, Viken Dadhaniya wrote:
>> For i2c read operation, we are getting gsi mode timeout due
>> to malformed TRE(Transfer Ring Element). Currently we are
>> configuring incorrect TRE sequence in gpi driver
>> (drivers/dma/qcom/gpi.c) as below
>>
>> - Sets up CONFIG
>> - Sets up DMA tre
>> - Sets up GO tre
>>
>> As per HPG(Hardware programming guide), We should configure TREs in below
>> sequence for any i2c transfer
>>
>> - Sets up CONFIG tre
>> - Sets up GO tre
>> - Sets up DMA tre
>>
>> For only write operation or write followed by read operation,
>> existing software sequence is correct.
>>
>> for only read operation, TRE sequence need to be corrected.
>> Hence, we have changed the sequence to submit GO tre before DMA tre.
>>
>> Tested covering i2c read/write transfer on QCM6490 RB3 board.
>>
>> Signed-off-by: Viken Dadhaniya <quic_vdadhani@...cinc.com>
>> Fixes: commit d8703554f4de ("i2c: qcom-geni: Add support for GPI DMA")
> 
> The format is:
> 
> Fixes: d8703554f4de ("i2c: qcom-geni: Add support for GPI DMA")
> 
> and goes above the SoB.
> 
>> ---
>> v1 -> v2:
>> - Remove redundant check.
>> - update commit log.
>> - add fix tag.
>> ---
>> ---
>>   drivers/i2c/busses/i2c-qcom-geni.c | 14 +++++++-------
>>   1 file changed, 7 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
>> index 0d2e7171e3a6..da94df466e83 100644
>> --- a/drivers/i2c/busses/i2c-qcom-geni.c
>> +++ b/drivers/i2c/busses/i2c-qcom-geni.c
>> @@ -613,20 +613,20 @@ static int geni_i2c_gpi_xfer(struct geni_i2c_dev *gi2c, struct i2c_msg msgs[], i
>>   
>>   		peripheral.addr = msgs[i].addr;
>>   
>> +		ret =  geni_i2c_gpi(gi2c, &msgs[i], &config,
>> +				    &tx_addr, &tx_buf, I2C_WRITE, gi2c->tx_c);
>> +		if (ret)
>> +			goto err;
>> +
>>   		if (msgs[i].flags & I2C_M_RD) {
>>   			ret =  geni_i2c_gpi(gi2c, &msgs[i], &config,
>>   					    &rx_addr, &rx_buf, I2C_READ, gi2c->rx_c);
>>   			if (ret)
>>   				goto err;
>> -		}
>> -
>> -		ret =  geni_i2c_gpi(gi2c, &msgs[i], &config,
>> -				    &tx_addr, &tx_buf, I2C_WRITE, gi2c->tx_c);
>> -		if (ret)
>> -			goto err;
>>   
>> -		if (msgs[i].flags & I2C_M_RD)
>>   			dma_async_issue_pending(gi2c->rx_c);
>> +		}
>> +
> 
> Bryan, could you please check here?
> 
> Thanks for your review!
> 
> Andi

Assuming the Fixes tag is fixed.

Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@...aro.org>
Tested-by: Bryan O'Donoghue <bryan.odonoghue@...aro.org> # qrb5165-rb5

---
bod