Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   "N, Pandith" <pandith.n@intel.com>
To:     Joe Perches <joe@perches.com>,
        "georgi.djakov@linaro.org" <georgi.djakov@linaro.org>,
        "linux-pm@vger.kernel.org" <linux-pm@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
CC:     "mgross@linux.intel.com" <mgross@linux.intel.com>,
        "Zhou, Furong" <furong.zhou@intel.com>,
        "Sangannavar, Mallikarjunappa" 
        <mallikarjunappa.sangannavar@intel.com>,
        "Raja Subramanian, Lakshmi Bai" 
        <lakshmi.bai.raja.subramanian@intel.com>
Subject: RE: [PATCH V6 1/1] interconnect: intel: Add Keem Bay noc driver
Thread-Topic: [PATCH V6 1/1] interconnect: intel: Add Keem Bay noc driver
Thread-Index: AQHXnjKFvPGsOLQFu0yhd4mKaNMQ96uNvIQAgAFzPgA=
Date:   Wed, 1 Sep 2021 13:50:15 +0000
Message-ID: <BYAPR11MB35281058ADB062E796338B7FE1CD9@BYAPR11MB3528.namprd11.prod.outlook.com>
References: <20210831063615.1021-1-pandith.n@intel.com>
 <1c5b485cc9b8836b09f99278233d9dc0ae991da7.camel@perches.com>
In-Reply-To: <1c5b485cc9b8836b09f99278233d9dc0ae991da7.camel@perches.com>
Accept-Language: en-US
Content-Language: en-US
dlp-product: dlpe-windows
dlp-reaction: no-action
dlp-version: 11.5.1.3
x-ms-exchange-antispam-messagedata-chunkcount: 1
x-ms-exchange-antispam-messagedata-0: =?us-ascii?Q?YcYmXBcP4F40QVDhwtIxHVIjD9k1ruH25eLj3EvwgcL37c6aopoubdomrvn8?=
 =?us-ascii?Q?DvrBlWiLaK9zUDCbfXjo/CSgwBZ52B3et+PUa1aoRXtdQRIFnznGujZQK3zr?=
 =?us-ascii?Q?4O92RgO5GmE+sxM4tsmAlAh8BHLjHc4YYjdORZV95CdfJIUa+xVmtYbIUkx7?=
 =?us-ascii?Q?E2aMY4UJP7J+VbL62l/vXxpsxQgbEvPvmsa8ULd3n6RnUnugmnB2nE/2Dm3g?=
 =?us-ascii?Q?Twl/qd8OHtHowspxFBpWNsQ+L6CBQP0IzADBDjiSrVtoJQSoopbByeiAyQ6d?=
 =?us-ascii?Q?ZJn37mNiHRiGFU2BB0LhRMlIInYkQ94fobcu0IyTdRhgfLkl7JDRErreVgIS?=
 =?us-ascii?Q?t1RmEzc6b3lF+0pUbPXsY367ZzuYyt7/sSja1l3m3b8Ske3+9/h5EzBNK9pb?=
 =?us-ascii?Q?wVJ3wbEy1prSf6db00OF8cRvre9Y4/v6NSI6dp3Kv3bpLcrxgoTfEHs9F22N?=
 =?us-ascii?Q?Wirnae935XF6U9AS7KMCDba4q15uolbGcEjn0riNM/ndlSkmfodSSswSL89M?=
 =?us-ascii?Q?eKCSpaB3KANLN8Bl35YIaQsCz3M7JozvScJGDmb4SCWUDKmNmEaFTXACEPOO?=
 =?us-ascii?Q?IVxME4E2QXlhKMbZSGcXxg2Rmetl6aObXUWvjHR7MF5Fb6lkJjDDT4jNrizm?=
 =?us-ascii?Q?NoIaSFCU59I77N/7QPQqm6DhrxgVqeueh1qcE13CRCD58DZNEtIKUIbbTAFe?=
 =?us-ascii?Q?jicy7zAFBTd2FM8BUZ8S1rYGvKdGuxZnyVV4hs0h1QU6IYg9BbtNnPPM22k6?=
 =?us-ascii?Q?TATbUXdtdRvkWADuMDpCsVUvLX7/wRyoyGG2pKtVSQaZ4APHJN4hQ9gWRyhT?=
 =?us-ascii?Q?eZMnaz7PeEWxAwJt0O7o8C2OdiZWpQ6l3WPmGITkQUl/7WFrOp6CfqyjRwrZ?=
 =?us-ascii?Q?rTuk2rgA/KgIjnZfxx1OQlEcSYzD7r8GqCBd853nyUrAF4eKPmKhK7Q/9esz?=
 =?us-ascii?Q?opHoz6LcGitTHQSsWmtrjvCBzEGdwsHIYxvsgqq12MFIPHiy6itH4hM4xbdB?=
 =?us-ascii?Q?lrapvbIbXDB3PW9rD27RmT+6YU2uf/hcPTJK7uSD8hBa2AQS/XwcIsjGoDp4?=
 =?us-ascii?Q?jERp29C8DVCb5Kx2M15rvSAH7k7qaJvTDQzpoD1baAOmEFWun7plPV84mBSG?=
 =?us-ascii?Q?oW783hn/iaa+k8j5BJtBH/a8k/NR+vjZbxI6okMr/R/76ERhV3i5hJP4jP3G?=
 =?us-ascii?Q?S9jNu4cIwULl2XlYUEiyC1isa+E7n9OA3LVcEaQze4Vtg+PXC8369C7ybuzE?=
 =?us-ascii?Q?sbaG+Wr7I5zEEUwzX+4YuG1oJMfsJ1K3ChLlxooQ2oJQynWmdr6EHzITU7AT?=
 =?us-ascii?Q?YvrzpvMq3GNQGiUd4jnkpY4K?=
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-AuthSource: BYAPR11MB3528.namprd11.prod.outlook.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 767bc19e-420b-4eca-629f-08d96d4f6da0
X-MS-Exchange-CrossTenant-originalarrivaltime: 01 Sep 2021 13:50:15.7418
 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 46c98d88-e344-4ed4-8496-4ed7712e255d
X-MS-Exchange-CrossTenant-mailboxtype: HOSTED
X-MS-Exchange-CrossTenant-userprincipalname: V2vCEts+7UN56VZYm5suYZz6Z11f5JkFZR/W1Q6xNSSLZfnCmClq73qFXiKSGdnpLM8Bwk23psMMuMYc3NT9EA==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: BY5PR11MB4419
X-OriginatorOrg: intel.com
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

Hi,

> -----Original Message-----
> From: Joe Perches <joe@perches.com>
> Sent: Tuesday, August 31, 2021 8:56 PM
> To: N, Pandith <pandith.n@intel.com>; georgi.djakov@linaro.org; linux-
> pm@vger.kernel.org; linux-kernel@vger.kernel.org
> Cc: mgross@linux.intel.com; Zhou, Furong <furong.zhou@intel.com>;
> Sangannavar, Mallikarjunappa <mallikarjunappa.sangannavar@intel.com>; Raj=
a
> Subramanian, Lakshmi Bai <lakshmi.bai.raja.subramanian@intel.com>
> Subject: Re: [PATCH V6 1/1] interconnect: intel: Add Keem Bay noc driver
>=20
> On Tue, 2021-08-31 at 12:06 +0530, pandith.n@intel.com wrote:
> > From: Pandith N <pandith.n@intel.com>
> >
> > Add support for Network on Chip(NOC) counters. Enable features to
> > configure and capture NOC probe counters, needed for DDR bandwidth
> > measurement. NOC driver is specific to Intel Keem Bay SOC. NOC
> > hardware counters are used for DDR statistics profiling, it is not rela=
ted to
> timers.
> > Interface details are provided in include/uapi/linux/noc_uapi.h
>=20
> trivial notes:
>=20
> > diff --git a/drivers/interconnect/intel/Kconfig
> > b/drivers/interconnect/intel/Kconfig
> []
> > +config INTERCONNECT_INTEL_KEEMBAY
> > +	tristate "Intel Keem Bay Enable DDR profiling using NOC"
> > +	depends on INTERCONNECT_INTEL || ARCH_KEEMBAY ||
> COMPILE_TEST
> > +	help
> > +	  Enable this option for DDR bandwidth measurements using NOC
> > +
> > +	  Add support for Network-on-chip (NOC) in DDR Subsystem(DSS).
> > +	  DSS NOC has capabilities to enable and get statistics profiling.
> > +	  NOC driver enables features to configure and capture NOC probe
> > +          counters, needed for DSS bandwidth measurement.
>=20
> Inconsistent tab/space indentation on this line
>=20
It will corrected with tab + 2 spaces

> > diff --git a/drivers/interconnect/intel/keembay-bwmon.c
> > b/drivers/interconnect/intel/keembay-bwmon.c
> []
> > +/**
> > + * flex_noc_setup() - Setup two counters for the NOC probe
> > + * @noc: NOC type to setup counters
> > + * @counter: Counter number to set up counter n and n+1
> > + * @trace_port: trace port number to setup counters
> > + *
> > + * This function will setup the counters for the trace port given.
>=20
> This seems to be unnecessary kernel-doc and if it is useful, the return v=
alue isn't
> described.
>=20
Will add description for return value

> > +int flex_noc_setup(enum noc_ss_type noc, enum noc_counter counter,
> > +int trace_port) {
> > +	int offset;
> > +
> > +	if (noc >=3D NOC_TYPE_MAX || counter >=3D NOC_COUNTER_MAX)
> > +		return -EINVAL;
> > +
> > +	offset =3D f_offset[counter / 2];
> > +
> > +	/* Stop ongoing stats */
> > +	noc_writel(MAINCTL, 0);
> > +	noc_writel(CFGCTL, 0);
> > +
> > +	/* Setup trace port and counters port select */
> > +	noc_writel(TRACEPORTSEL, trace_port);
> > +	noc_writel((c_offset[counter] + C_PORTSEL), trace_port);
>=20
> Lots of unnecessary parentheses
>=20
Will change as below :=20
noc_writel(c_offset[counter] + C_PORTSEL, trace_port);

> > +	noc_writel((c_offset[counter + 1] + C_PORTSEL), trace_port);
> > +
> > +	/* Setup counter sources & triggers, Alarm mode - OFF */
> > +	noc_writel((c_offset[counter] + C_SRC), COUNTERS_0_SRC_VAL);
> > +	noc_writel((c_offset[counter] + C_ALARMMODE),
> COUNTERS_ALARMMODE_VAL);
> > +	noc_writel((c_offset[counter + 1] + C_SRC), COUNTERS_1_SRC_VAL);
> > +	noc_writel((c_offset[counter + 1] + C_ALARMMODE),
> > +		   COUNTERS_ALARMMODE_VAL);
>=20
> []
Will correct unnecessary parenthesis in above 4 statements
=20
>=20
> > +enum noc_status flexnoc_counter_capture(enum noc_ss_type noc,
> > +					enum noc_counter counter, u32
> *value) {
> > +	unsigned long j0, j1, delay;
> > +	u32 c0_0, c0_1;
> > +
> > +	if (noc >=3D NOC_TYPE_MAX ||
> > +	    counter >=3D NOC_COUNTER_MAX  ||
> > +	    !value)
> > +		return NOC_PROBE_ERR_INVALID_ARGS;
> > +
> > +	delay =3D msecs_to_jiffies(NOC_CAPTURE_TIMEOUT_MSEC);
> > +	j0 =3D jiffies;
> > +	j1 =3D j0 + delay;
>=20
> j0 and j1 seem unnecessary
>=20
Yes, will change it to single timeout variable.

> 	timeout =3D jiffies + msecs_to_jiffies(NOC_CAPTURE_TIMEOUT_MSEC);
>=20
> > +	do {
> > +		c0_0 =3D noc_readl((c_offset[counter] + C_VAL));
> > +		usleep_range(10000, 11000);
>=20
> Seems a long time.
>=20
Will review if this time can be optimized.

> > +		c0_1 =3D noc_readl((c_offset[counter] + C_VAL));
> > +		/* If mainctrl is zero , return error */
> > +		if (noc_readl(MAINCTL) =3D=3D 0)
> > +			return NOC_PROBE_ERR_IN_PROGRESS;
> > +		/* If counters are zero, keep reading */
> > +		if (0 =3D=3D c0_0 && 0 =3D=3D c0_1) {
> > +			break;
> > +		} else if (c0_0 !=3D c0_1) {
> > +			continue;
> > +		} else {
> > +			/* counters look good break the while */
> > +			break;
> > +		}
> > +	} while (time_before(jiffies, j1));
>=20
> 	} while (time_before(jiffies, timeout);
>
Variable will be renamed as timeout.
=20
> []
>=20
> > +static long noc_ioctl(struct file *file, unsigned int cmd, unsigned
> > +long arg) {
> > +	struct flexnoc_countercapture capture_data;
> > +	void __user *argp =3D (void __user *)arg;
> > +	struct flexnoc_probestart probe_data;
> > +	struct flexnoc_setup setup_data;
> > +	int rc;
> > +
> > +	if (!arg) {
> > +		pr_err("NOC: Null pointer from user\n");
>=20
> Perhaps useful to add #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt near th=
e
> top of the file.
>=20
will add this line to the top of the file
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

Regards,
Pandith