linux-kernel - RE: [PATCH v7 4/4] perf/smmuv3: Enable HiSilicon Erratum 162001800 quirk

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] [day] [month] [year] [list]

Date:   Thu, 4 Apr 2019 16:31:55 +0000
From:   Shameerali Kolothum Thodi <shameerali.kolothum.thodi@...wei.com>
To:     Will Deacon <will.deacon@....com>
CC:     "lorenzo.pieralisi@....com" <lorenzo.pieralisi@....com>,
        "robin.murphy@....com" <robin.murphy@....com>,
        "andrew.murray@....com" <andrew.murray@....com>,
        "jean-philippe.brucker@....com" <jean-philippe.brucker@....com>,
        "mark.rutland@....com" <mark.rutland@....com>,
        "Guohanjun (Hanjun Guo)" <guohanjun@...wei.com>,
        "John Garry" <john.garry@...wei.com>,
        "pabba@...eaurora.org" <pabba@...eaurora.org>,
        "vkilari@...eaurora.org" <vkilari@...eaurora.org>,
        "rruigrok@...eaurora.org" <rruigrok@...eaurora.org>,
        "linux-acpi@...r.kernel.org" <linux-acpi@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "linux-arm-kernel@...ts.infradead.org" 
        <linux-arm-kernel@...ts.infradead.org>,
        Linuxarm <linuxarm@...wei.com>,
        "neil.m.leeder@...il.com" <neil.m.leeder@...il.com>
Subject: RE: [PATCH v7 4/4] perf/smmuv3: Enable HiSilicon Erratum 162001800
 quirk



> -----Original Message-----
> From: Will Deacon [mailto:will.deacon@....com]
> Sent: 04 April 2019 16:47
> To: Shameerali Kolothum Thodi <shameerali.kolothum.thodi@...wei.com>
> Cc: lorenzo.pieralisi@....com; robin.murphy@....com;
> andrew.murray@....com; jean-philippe.brucker@....com;
> mark.rutland@....com; Guohanjun (Hanjun Guo) <guohanjun@...wei.com>;
> John Garry <john.garry@...wei.com>; pabba@...eaurora.org;
> vkilari@...eaurora.org; rruigrok@...eaurora.org; linux-acpi@...r.kernel.org;
> linux-kernel@...r.kernel.org; linux-arm-kernel@...ts.infradead.org; Linuxarm
> <linuxarm@...wei.com>; neil.m.leeder@...il.com
> Subject: Re: [PATCH v7 4/4] perf/smmuv3: Enable HiSilicon Erratum 162001800
> quirk
> 
> On Tue, Mar 26, 2019 at 03:17:53PM +0000, Shameer Kolothum wrote:
> > HiSilicon erratum 162001800 describes the limitation of
> > SMMUv3 PMCG implementation on HiSilicon Hip08 platforms.
> >
> > On these platforms, the PMCG event counter registers
> > (SMMU_PMCG_EVCNTRn) are read only and as a result it
> > is not possible to set the initial counter period value
> > on event monitor start.
> >
> > To work around this, the current value of the counter
> > is read and used for delta calculations. OEM information
> > from ACPI header is used to identify the affected hardware
> > platforms.
> >
> > Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@...wei.com>
> > Reviewed-by: Hanjun Guo <hanjun.guo@...aro.org>
> > Reviewed-by: Robin Murphy <robin.murphy@....com>
> > ---
> >  drivers/acpi/arm64/iort.c     | 16 ++++++++++++++-
> >  drivers/perf/arm_smmuv3_pmu.c | 48
> ++++++++++++++++++++++++++++++++++++-------
> >  include/linux/acpi_iort.h     |  1 +
> >  3 files changed, 57 insertions(+), 8 deletions(-)
> >
> > diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
> > index e2c9b26..4dc68de 100644
> > --- a/drivers/acpi/arm64/iort.c
> > +++ b/drivers/acpi/arm64/iort.c
> > @@ -1366,9 +1366,23 @@ static void __init
> arm_smmu_v3_pmcg_init_resources(struct resource *res,
> >  				       ACPI_EDGE_SENSITIVE, &res[2]);
> >  }
> >
> > +static struct acpi_platform_list pmcg_plat_info[] __initdata = {
> > +	/* HiSilicon Hip08 Platform */
> > +	{"HISI  ", "HIP08   ", 0, ACPI_SIG_IORT, greater_than_or_equal, 0,
> 
> Passing integer constant 0 for the reason feels wrong to me. I'm going to
> change it to "Erratum #162001800" and also add an entry to
> silicon-errata.txt.
> 
> Please shout if that's not ok.

Thanks Will for taking a look at this series. The proposed changes are fine to me.

Shameer