linux-kernel - Re: [PATCH v3 14/18] coresight tmc etr: Cleanup AXICTL register handling

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: <6b7c32c2-a372-4666-1d77-830155ab8f33@arm.com>
Date:   Tue, 18 Jul 2017 10:07:36 +0100
From:   Suzuki K Poulose <Suzuki.Poulose@....com>
To:     Mathieu Poirier <mathieu.poirier@...aro.org>
Cc:     linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        mike.leach@...aro.org
Subject: Re: [PATCH v3 14/18] coresight tmc etr: Cleanup AXICTL register
 handling

On 17/07/17 18:06, Mathieu Poirier wrote:
> On Fri, Jul 14, 2017 at 02:04:19PM +0100, Suzuki K Poulose wrote:
>> This patch cleans up how we setup the AXICTL register on
>> TMC ETR. At the moment we don't set the CacheCtrl bits, which
>> drives the arcache and awcache bits on AXI bus specifying the
>> cacheablitiy. Set this to Write-back Read and Write-allocate.
>>
>> Cc: Mathieu Poirier <mathieu.poirier@...aro.org>
>> Signed-off-by: Suzuki K Poulose <suzuki.poulose@....com>
>> ---
>>  drivers/hwtracing/coresight/coresight-tmc-etr.c | 10 +++-------
>>  drivers/hwtracing/coresight/coresight-tmc.h     | 17 ++++++++++++++++-
>>  2 files changed, 19 insertions(+), 8 deletions(-)
>>
>> diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
>> index ff11b92..4aa5d36 100644
>> --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
>> +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
>> @@ -36,13 +36,9 @@ static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
>>  	writel_relaxed(TMC_MODE_CIRCULAR_BUFFER, drvdata->base + TMC_MODE);
>>
>>  	axictl = readl_relaxed(drvdata->base + TMC_AXICTL);
>> -	axictl |= TMC_AXICTL_WR_BURST_16;
>> -	writel_relaxed(axictl, drvdata->base + TMC_AXICTL);
>> -	axictl &= ~TMC_AXICTL_SCT_GAT_MODE;
>> -	writel_relaxed(axictl, drvdata->base + TMC_AXICTL);
>> -	axictl = (axictl &
>> -		  ~(TMC_AXICTL_PROT_CTL_B0 | TMC_AXICTL_PROT_CTL_B1)) |
>> -		  TMC_AXICTL_PROT_CTL_B1;
>> +	axictl &= ~TMC_AXICTL_CLEAR_MASK;
>> +	axictl |= (TMC_AXICTL_PROT_CTL_B1 | TMC_AXICTL_WR_BURST_16);
>> +	axictl |= TMC_AXICTL_AxCACHE_OS;
>>  	writel_relaxed(axictl, drvdata->base + TMC_AXICTL);
>>  	tmc_write_dba(drvdata, drvdata->paddr);
>>
>> diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h
>> index a0668f6..5d6d7e5 100644
>> --- a/drivers/hwtracing/coresight/coresight-tmc.h
>> +++ b/drivers/hwtracing/coresight/coresight-tmc.h
>> @@ -55,11 +55,26 @@
>>  #define TMC_STS_TMCREADY_BIT	2
>>  #define TMC_STS_FULL		BIT(0)
>>  #define TMC_STS_TRIGGERED	BIT(1)
>> -/* TMC_AXICTL - 0x110 */
>> +/*
>> + * TMC_AXICTL - 0x110
>> + *
>> + * TMC AXICTL format for SoC-400
>> + * 	Bits [0-1]	: ProtCtrlBit0-1
>> + * 	Bits [2-5]	: CacheCtrlBits 0-3 (AxCACHE)
>> + * 	Bit  6		: Reserved
>> + * 	Bit  7		: ScatterGatherMode
>> + * 	Bits [8-11]	: WrBurstLen
>> + * 	Bits [12-31]	: Reserved.
>> + */
>> +#define TMC_AXICTL_CLEAR_MASK 0xfbf
>> +
>>  #define TMC_AXICTL_PROT_CTL_B0	BIT(0)
>>  #define TMC_AXICTL_PROT_CTL_B1	BIT(1)
>>  #define TMC_AXICTL_SCT_GAT_MODE	BIT(7)
>>  #define TMC_AXICTL_WR_BURST_16	0xF00
>> +/* Write-back Read and Write-allocate */
>> +#define TMC_AXICTL_AxCACHE_OS	(0xf << 2)
>
> Please use a capital 'x' here.

Sure, fixed in the next version.

>
> Also this patch is giving me a few checkpatch.pl warnings.
>

Thats because of the space before the TABs in the comment section
above describing the bits. I have fixed it now, though I am not sure
if it checkpatch should really complain about it.

Cheers
Suzuki

>> +
>>  /* TMC_FFCR - 0x304 */
>>  #define TMC_FFCR_FLUSHMAN_BIT	6
>>  #define TMC_FFCR_EN_FMT		BIT(0)
>> --
>> 2.7.5
>>