linux-kernel - Re: [PATCH v11 2/9] ARM: l2c: use l2c_write_sec() for restoring latency and filter regs

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: <54AD0EDF.6080709@samsung.com>
Date:	Wed, 07 Jan 2015 11:47:59 +0100
From:	Marek Szyprowski <m.szyprowski@...sung.com>
To:	Nishanth Menon <nm@...com>
Cc:	linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
	Tomasz Figa <tomasz.figa@...il.com>,
	Kyungmin Park <kyungmin.park@...sung.com>,
	linux-samsung-soc@...r.kernel.org, linux-omap@...r.kernel.org,
	Arnd Bergmann <arnd@...db.de>, Olof Johansson <olof@...om.net>,
	Russell King - ARM Linux <linux@....linux.org.uk>,
	Kukjin Kim <kgene.kim@...sung.com>, lauraa@...eaurora.org,
	linus.walleij@...aro.org, tony@...mide.com, drake@...lessm.com,
	loeliger@...il.com, Mark Rutland <mark.rutland@....com>,
	khilman@...aro.org
Subject: Re: [PATCH v11 2/9] ARM: l2c: use l2c_write_sec() for restoring
 latency and filter regs

Hello,

On 2015-01-05 18:20, Nishanth Menon wrote:
> On 13:19-20150105, Marek Szyprowski wrote:
>> All four register for latency and filter settings cannot be written in
>> non-secure mode and they should go through l2c_write_sec(). More on this
>> can be found in CoreLink Level 2 Cache Controller L2C-310 Technical
>> Reference Manual, 3.2. Register summary, table 3.1. This have been checked
>> the TRM for r3p3, but it should be uniform for all revisions.
>>
>> Reported-by: Nishanth Menon <nm@...com>
>> Suggested-by: Tomasz Figa <tomasz.figa@...il.com>
>> Signed-off-by: Marek Szyprowski <m.szyprowski@...sung.com>
>> ---
>>   arch/arm/mm/cache-l2x0.c | 16 ++++++++--------
>>   1 file changed, 8 insertions(+), 8 deletions(-)
>>
>> diff --git a/arch/arm/mm/cache-l2x0.c b/arch/arm/mm/cache-l2x0.c
>> index 5e65ca8dea62..0aeeaa95c42d 100644
>> --- a/arch/arm/mm/cache-l2x0.c
>> +++ b/arch/arm/mm/cache-l2x0.c
>> @@ -623,14 +623,14 @@ static void l2c310_resume(void)
>>   		unsigned revision;
>>   
>>   		/* restore pl310 setup */
>> -		writel_relaxed(l2x0_saved_regs.tag_latency,
>> -			       base + L310_TAG_LATENCY_CTRL);
>> -		writel_relaxed(l2x0_saved_regs.data_latency,
>> -			       base + L310_DATA_LATENCY_CTRL);
>> -		writel_relaxed(l2x0_saved_regs.filter_end,
>> -			       base + L310_ADDR_FILTER_END);
>> -		writel_relaxed(l2x0_saved_regs.filter_start,
>> -			       base + L310_ADDR_FILTER_START);
>> +		l2c_write_sec(l2x0_saved_regs.tag_latency, base,
>> +			      L310_TAG_LATENCY_CTRL);
>> +		l2c_write_sec(l2x0_saved_regs.data_latency, base,
>> +			      L310_DATA_LATENCY_CTRL);
>> +		l2c_write_sec(l2x0_saved_regs.filter_end, base,
>> +			      L310_ADDR_FILTER_END);
>> +		l2c_write_sec(l2x0_saved_regs.filter_start, base,
>> +			      L310_ADDR_FILTER_START);
>>   
>>   		revision = readl_relaxed(base + L2X0_CACHE_ID) &
>>   				L2X0_CACHE_ID_RTL_MASK;
> Do you need the following as well at this point in the patch series?
> Agreed that the writes will disappear later in the series.

Right. Thanks for pointing this. I will send an updated version, which
will also fix the checkpatch --strict issues.

> diff --git a/arch/arm/mm/cache-l2x0.c b/arch/arm/mm/cache-l2x0.c
> index 0aeeaa9..7afab37 100644
> --- a/arch/arm/mm/cache-l2x0.c
> +++ b/arch/arm/mm/cache-l2x0.c
> @@ -1135,28 +1135,28 @@ static void __init l2c310_of_parse(const struct device_node *np,
>   
>   	of_property_read_u32_array(np, "arm,tag-latency", tag, ARRAY_SIZE(tag));
>   	if (tag[0] && tag[1] && tag[2])
> -		writel_relaxed(
> +		l2c_write_sec(
>   			L310_LATENCY_CTRL_RD(tag[0] - 1) |
>   			L310_LATENCY_CTRL_WR(tag[1] - 1) |
>   			L310_LATENCY_CTRL_SETUP(tag[2] - 1),
> -			l2x0_base + L310_TAG_LATENCY_CTRL);
> +			l2x0_base, L310_TAG_LATENCY_CTRL);
>   
>   	of_property_read_u32_array(np, "arm,data-latency",
>   				   data, ARRAY_SIZE(data));
>   	if (data[0] && data[1] && data[2])
> -		writel_relaxed(
> +		l2c_write_sec(
>   			L310_LATENCY_CTRL_RD(data[0] - 1) |
>   			L310_LATENCY_CTRL_WR(data[1] - 1) |
>   			L310_LATENCY_CTRL_SETUP(data[2] - 1),
> -			l2x0_base + L310_DATA_LATENCY_CTRL);
> +			l2x0_base,  L310_DATA_LATENCY_CTRL);
>   
>   	of_property_read_u32_array(np, "arm,filter-ranges",
>   				   filter, ARRAY_SIZE(filter));
>   	if (filter[1]) {
> -		writel_relaxed(ALIGN(filter[0] + filter[1], SZ_1M),
> -			       l2x0_base + L310_ADDR_FILTER_END);
> -		writel_relaxed((filter[0] & ~(SZ_1M - 1)) | L310_ADDR_FILTER_EN,
> -			       l2x0_base + L310_ADDR_FILTER_START);
> +		l2c_write_sec(ALIGN(filter[0] + filter[1], SZ_1M),
> +			       l2x0_base, L310_ADDR_FILTER_END);
> +		l2c_write_sec((filter[0] & ~(SZ_1M - 1)) | L310_ADDR_FILTER_EN,
> +			       l2x0_base, L310_ADDR_FILTER_START);
>   	}
>   
>   	ret = l2x0_cache_size_of_parse(np, aux_val, aux_mask, &assoc, SZ_512K);
>   

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/