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* [PATCH] soc: imx-scu: Add SoC UID(unique identifier) support
@ 2019-06-26  7:07 Anson.Huang
  2019-06-26 12:41 ` Daniel Baluta
  0 siblings, 1 reply; 7+ messages in thread
From: Anson.Huang @ 2019-06-26  7:07 UTC (permalink / raw)
  To: shawnguo, s.hauer, kernel, festevam, aisheng.dong, abel.vesa,
	linux-arm-kernel, linux-kernel
  Cc: Linux-imx

From: Anson Huang <Anson.Huang@nxp.com>

Add i.MX SCU SoC's UID(unique identifier) support, user
can read it from sysfs:

root@imx8qxpmek:~# cat /sys/devices/soc0/soc_uid
7B64280B57AC1898

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
---
 drivers/soc/imx/soc-imx-scu.c | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/drivers/soc/imx/soc-imx-scu.c b/drivers/soc/imx/soc-imx-scu.c
index 676f612..8d322a1 100644
--- a/drivers/soc/imx/soc-imx-scu.c
+++ b/drivers/soc/imx/soc-imx-scu.c
@@ -27,6 +27,36 @@ struct imx_sc_msg_misc_get_soc_id {
 	} data;
 } __packed;
 
+struct imx_sc_msg_misc_get_soc_uid {
+	struct imx_sc_rpc_msg hdr;
+	u32 uid_low;
+	u32 uid_high;
+} __packed;
+
+static ssize_t soc_uid_show(struct device *dev,
+			    struct device_attribute *attr, char *buf)
+{
+	struct imx_sc_msg_misc_get_soc_uid msg;
+	struct imx_sc_rpc_msg *hdr = &msg.hdr;
+	u64 soc_uid;
+
+	hdr->ver = IMX_SC_RPC_VERSION;
+	hdr->svc = IMX_SC_RPC_SVC_MISC;
+	hdr->func = IMX_SC_MISC_FUNC_UNIQUE_ID;
+	hdr->size = 1;
+
+	/* the return value of SCU FW is in correct, skip return value check */
+	imx_scu_call_rpc(soc_ipc_handle, &msg, true);
+
+	soc_uid = msg.uid_high;
+	soc_uid <<= 32;
+	soc_uid |= msg.uid_low;
+
+	return sprintf(buf, "%016llX\n", soc_uid);
+}
+
+static DEVICE_ATTR_RO(soc_uid);
+
 static int imx_scu_soc_id(void)
 {
 	struct imx_sc_msg_misc_get_soc_id msg;
@@ -102,6 +132,11 @@ static int imx_scu_soc_probe(struct platform_device *pdev)
 		goto free_revision;
 	}
 
+	ret = device_create_file(soc_device_to_device(soc_dev),
+				 &dev_attr_soc_uid);
+	if (ret)
+		goto free_revision;
+
 	return 0;
 
 free_revision:
-- 
2.7.4


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^ permalink raw reply related	[flat|nested] 7+ messages in thread

* Re: [PATCH] soc: imx-scu: Add SoC UID(unique identifier) support
  2019-06-26  7:07 [PATCH] soc: imx-scu: Add SoC UID(unique identifier) support Anson.Huang
@ 2019-06-26 12:41 ` Daniel Baluta
  2019-06-27  0:48   ` Anson Huang
  0 siblings, 1 reply; 7+ messages in thread
From: Daniel Baluta @ 2019-06-26 12:41 UTC (permalink / raw)
  To: Anson Huang
  Cc: Aisheng Dong, Abel Vesa, Shawn Guo, Sascha Hauer,
	Linux Kernel Mailing List, Daniel Baluta, dl-linux-imx,
	Pengutronix Kernel Team, Fabio Estevam, linux-arm-kernel

On Wed, Jun 26, 2019 at 10:06 AM <Anson.Huang@nxp.com> wrote:
>
> From: Anson Huang <Anson.Huang@nxp.com>
>
> Add i.MX SCU SoC's UID(unique identifier) support, user
> can read it from sysfs:
>
> root@imx8qxpmek:~# cat /sys/devices/soc0/soc_uid
> 7B64280B57AC1898
>
> Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> ---
>  drivers/soc/imx/soc-imx-scu.c | 35 +++++++++++++++++++++++++++++++++++
>  1 file changed, 35 insertions(+)
>
> diff --git a/drivers/soc/imx/soc-imx-scu.c b/drivers/soc/imx/soc-imx-scu.c
> index 676f612..8d322a1 100644
> --- a/drivers/soc/imx/soc-imx-scu.c
> +++ b/drivers/soc/imx/soc-imx-scu.c
> @@ -27,6 +27,36 @@ struct imx_sc_msg_misc_get_soc_id {
>         } data;
>  } __packed;
>
> +struct imx_sc_msg_misc_get_soc_uid {
> +       struct imx_sc_rpc_msg hdr;
> +       u32 uid_low;
> +       u32 uid_high;
> +} __packed;
> +
> +static ssize_t soc_uid_show(struct device *dev,
> +                           struct device_attribute *attr, char *buf)
> +{
> +       struct imx_sc_msg_misc_get_soc_uid msg;
> +       struct imx_sc_rpc_msg *hdr = &msg.hdr;
> +       u64 soc_uid;
> +
> +       hdr->ver = IMX_SC_RPC_VERSION;
> +       hdr->svc = IMX_SC_RPC_SVC_MISC;
> +       hdr->func = IMX_SC_MISC_FUNC_UNIQUE_ID;
> +       hdr->size = 1;
> +
> +       /* the return value of SCU FW is in correct, skip return value check */

Why do you mean by "in correct"?
> +       imx_scu_call_rpc(soc_ipc_handle, &msg, true);
> +
> +       soc_uid = msg.uid_high;
> +       soc_uid <<= 32;
> +       soc_uid |= msg.uid_low;
> +
> +       return sprintf(buf, "%016llX\n", soc_uid);

snprintf?

> +}
> +
> +static DEVICE_ATTR_RO(soc_uid);
> +
>  static int imx_scu_soc_id(void)
>  {
>         struct imx_sc_msg_misc_get_soc_id msg;
> @@ -102,6 +132,11 @@ static int imx_scu_soc_probe(struct platform_device *pdev)
>                 goto free_revision;
>         }
>
> +       ret = device_create_file(soc_device_to_device(soc_dev),
> +                                &dev_attr_soc_uid);
> +       if (ret)
> +               goto free_revision;
> +
>         return 0;
>
>  free_revision:
> --
> 2.7.4
>

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linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 7+ messages in thread

* RE: [PATCH] soc: imx-scu: Add SoC UID(unique identifier) support
  2019-06-26 12:41 ` Daniel Baluta
@ 2019-06-27  0:48   ` Anson Huang
  2019-06-27  6:43     ` Daniel Baluta
  0 siblings, 1 reply; 7+ messages in thread
From: Anson Huang @ 2019-06-27  0:48 UTC (permalink / raw)
  To: Daniel Baluta
  Cc: Aisheng Dong, Abel Vesa, Shawn Guo, Sascha Hauer,
	Linux Kernel Mailing List, Daniel Baluta, dl-linux-imx,
	Pengutronix Kernel Team, Fabio Estevam, linux-arm-kernel

Hi, Daniel

> -----Original Message-----
> From: Daniel Baluta <daniel.baluta@gmail.com>
> Sent: Wednesday, June 26, 2019 8:42 PM
> To: Anson Huang <anson.huang@nxp.com>
> Cc: Shawn Guo <shawnguo@kernel.org>; Sascha Hauer
> <s.hauer@pengutronix.de>; Pengutronix Kernel Team
> <kernel@pengutronix.de>; Fabio Estevam <festevam@gmail.com>; Aisheng
> Dong <aisheng.dong@nxp.com>; Abel Vesa <abel.vesa@nxp.com>; linux-
> arm-kernel <linux-arm-kernel@lists.infradead.org>; Linux Kernel Mailing List
> <linux-kernel@vger.kernel.org>; dl-linux-imx <linux-imx@nxp.com>; Daniel
> Baluta <daniel.baluta@nxp.com>
> Subject: Re: [PATCH] soc: imx-scu: Add SoC UID(unique identifier) support
> 
> On Wed, Jun 26, 2019 at 10:06 AM <Anson.Huang@nxp.com> wrote:
> >
> > From: Anson Huang <Anson.Huang@nxp.com>
> >
> > Add i.MX SCU SoC's UID(unique identifier) support, user can read it
> > from sysfs:
> >
> > root@imx8qxpmek:~# cat /sys/devices/soc0/soc_uid
> > 7B64280B57AC1898
> >
> > Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> > ---
> >  drivers/soc/imx/soc-imx-scu.c | 35
> > +++++++++++++++++++++++++++++++++++
> >  1 file changed, 35 insertions(+)
> >
> > diff --git a/drivers/soc/imx/soc-imx-scu.c
> > b/drivers/soc/imx/soc-imx-scu.c index 676f612..8d322a1 100644
> > --- a/drivers/soc/imx/soc-imx-scu.c
> > +++ b/drivers/soc/imx/soc-imx-scu.c
> > @@ -27,6 +27,36 @@ struct imx_sc_msg_misc_get_soc_id {
> >         } data;
> >  } __packed;
> >
> > +struct imx_sc_msg_misc_get_soc_uid {
> > +       struct imx_sc_rpc_msg hdr;
> > +       u32 uid_low;
> > +       u32 uid_high;
> > +} __packed;
> > +
> > +static ssize_t soc_uid_show(struct device *dev,
> > +                           struct device_attribute *attr, char *buf)
> > +{
> > +       struct imx_sc_msg_misc_get_soc_uid msg;
> > +       struct imx_sc_rpc_msg *hdr = &msg.hdr;
> > +       u64 soc_uid;
> > +
> > +       hdr->ver = IMX_SC_RPC_VERSION;
> > +       hdr->svc = IMX_SC_RPC_SVC_MISC;
> > +       hdr->func = IMX_SC_MISC_FUNC_UNIQUE_ID;
> > +       hdr->size = 1;
> > +
> > +       /* the return value of SCU FW is in correct, skip return value
> > + check */
> 
> Why do you mean by "in correct"?

I made a mistake, it should be "incorrect", the existing SCFW of this API returns
an error value even this API is successfully called, to make it work with current
SCFW, I have to skip the return value check for this API for now. Will send V2 patch
to fix this typo.

> > +       imx_scu_call_rpc(soc_ipc_handle, &msg, true);
> > +
> > +       soc_uid = msg.uid_high;
> > +       soc_uid <<= 32;
> > +       soc_uid |= msg.uid_low;
> > +
> > +       return sprintf(buf, "%016llX\n", soc_uid);
> 
> snprintf?

The snprintf is to avoid buffer overflow, which in this case, I don't know the size
of "buf", and the value(u64) to be printed is with fixed length of 64, so I think
sprint is just OK.

Anson.
> 
> > +}
> > +
> > +static DEVICE_ATTR_RO(soc_uid);
> > +
> >  static int imx_scu_soc_id(void)
> >  {
> >         struct imx_sc_msg_misc_get_soc_id msg; @@ -102,6 +132,11 @@
> > static int imx_scu_soc_probe(struct platform_device *pdev)
> >                 goto free_revision;
> >         }
> >
> > +       ret = device_create_file(soc_device_to_device(soc_dev),
> > +                                &dev_attr_soc_uid);
> > +       if (ret)
> > +               goto free_revision;
> > +
> >         return 0;
> >
> >  free_revision:
> > --
> > 2.7.4
> >
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linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [PATCH] soc: imx-scu: Add SoC UID(unique identifier) support
  2019-06-27  0:48   ` Anson Huang
@ 2019-06-27  6:43     ` Daniel Baluta
  2019-06-27  7:01       ` Anson Huang
  0 siblings, 1 reply; 7+ messages in thread
From: Daniel Baluta @ 2019-06-27  6:43 UTC (permalink / raw)
  To: Anson Huang
  Cc: Aisheng Dong, Abel Vesa, Shawn Guo, Sascha Hauer,
	Linux Kernel Mailing List, Daniel Baluta, dl-linux-imx,
	Pengutronix Kernel Team, Fabio Estevam, linux-arm-kernel

On Thu, Jun 27, 2019 at 3:48 AM Anson Huang <anson.huang@nxp.com> wrote:
>
> Hi, Daniel
>
> > -----Original Message-----
> > From: Daniel Baluta <daniel.baluta@gmail.com>
> > Sent: Wednesday, June 26, 2019 8:42 PM
> > To: Anson Huang <anson.huang@nxp.com>
> > Cc: Shawn Guo <shawnguo@kernel.org>; Sascha Hauer
> > <s.hauer@pengutronix.de>; Pengutronix Kernel Team
> > <kernel@pengutronix.de>; Fabio Estevam <festevam@gmail.com>; Aisheng
> > Dong <aisheng.dong@nxp.com>; Abel Vesa <abel.vesa@nxp.com>; linux-
> > arm-kernel <linux-arm-kernel@lists.infradead.org>; Linux Kernel Mailing List
> > <linux-kernel@vger.kernel.org>; dl-linux-imx <linux-imx@nxp.com>; Daniel
> > Baluta <daniel.baluta@nxp.com>
> > Subject: Re: [PATCH] soc: imx-scu: Add SoC UID(unique identifier) support
> >
> > On Wed, Jun 26, 2019 at 10:06 AM <Anson.Huang@nxp.com> wrote:
> > >
> > > From: Anson Huang <Anson.Huang@nxp.com>
> > >
> > > Add i.MX SCU SoC's UID(unique identifier) support, user can read it
> > > from sysfs:
> > >
> > > root@imx8qxpmek:~# cat /sys/devices/soc0/soc_uid
> > > 7B64280B57AC1898
> > >
> > > Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> > > ---
> > >  drivers/soc/imx/soc-imx-scu.c | 35
> > > +++++++++++++++++++++++++++++++++++
> > >  1 file changed, 35 insertions(+)
> > >
> > > diff --git a/drivers/soc/imx/soc-imx-scu.c
> > > b/drivers/soc/imx/soc-imx-scu.c index 676f612..8d322a1 100644
> > > --- a/drivers/soc/imx/soc-imx-scu.c
> > > +++ b/drivers/soc/imx/soc-imx-scu.c
> > > @@ -27,6 +27,36 @@ struct imx_sc_msg_misc_get_soc_id {
> > >         } data;
> > >  } __packed;
> > >
> > > +struct imx_sc_msg_misc_get_soc_uid {
> > > +       struct imx_sc_rpc_msg hdr;
> > > +       u32 uid_low;
> > > +       u32 uid_high;
> > > +} __packed;
> > > +
> > > +static ssize_t soc_uid_show(struct device *dev,
> > > +                           struct device_attribute *attr, char *buf)
> > > +{
> > > +       struct imx_sc_msg_misc_get_soc_uid msg;
> > > +       struct imx_sc_rpc_msg *hdr = &msg.hdr;
> > > +       u64 soc_uid;
> > > +
> > > +       hdr->ver = IMX_SC_RPC_VERSION;
> > > +       hdr->svc = IMX_SC_RPC_SVC_MISC;
> > > +       hdr->func = IMX_SC_MISC_FUNC_UNIQUE_ID;
> > > +       hdr->size = 1;
> > > +
> > > +       /* the return value of SCU FW is in correct, skip return value
> > > + check */
> >
> > Why do you mean by "in correct"?
>
> I made a mistake, it should be "incorrect", the existing SCFW of this API returns
> an error value even this API is successfully called, to make it work with current
> SCFW, I have to skip the return value check for this API for now. Will send V2 patch
> to fix this typo.

Thanks Anson! It makes sense now. It is a little bit sad though because we won't
know when there is a "real" error :).

Lets update the comment to be more specific:

/* SCFW FW API always returns an error even the function is
successfully executed, so skip returned value */


> > > +       imx_scu_call_rpc(soc_ipc_handle, &msg, true);
> > > +
> > > +       soc_uid = msg.uid_high;
> > > +       soc_uid <<= 32;
> > > +       soc_uid |= msg.uid_low;
> > > +
> > > +       return sprintf(buf, "%016llX\n", soc_uid);
> >
> > snprintf?
>
> The snprintf is to avoid buffer overflow, which in this case, I don't know the size
> of "buf", and the value(u64) to be printed is with fixed length of 64, so I think
> sprint is just OK.

Ok.

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 7+ messages in thread

* RE: [PATCH] soc: imx-scu: Add SoC UID(unique identifier) support
  2019-06-27  6:43     ` Daniel Baluta
@ 2019-06-27  7:01       ` Anson Huang
  2019-07-02  6:42         ` Marco Felsch
  0 siblings, 1 reply; 7+ messages in thread
From: Anson Huang @ 2019-06-27  7:01 UTC (permalink / raw)
  To: Daniel Baluta
  Cc: Aisheng Dong, Abel Vesa, Shawn Guo, Sascha Hauer,
	Linux Kernel Mailing List, Daniel Baluta, dl-linux-imx,
	Pengutronix Kernel Team, Fabio Estevam, linux-arm-kernel

Hi, Daniel

> -----Original Message-----
> From: Daniel Baluta <daniel.baluta@gmail.com>
> Sent: Thursday, June 27, 2019 2:44 PM
> To: Anson Huang <anson.huang@nxp.com>
> Cc: Shawn Guo <shawnguo@kernel.org>; Sascha Hauer
> <s.hauer@pengutronix.de>; Pengutronix Kernel Team
> <kernel@pengutronix.de>; Fabio Estevam <festevam@gmail.com>; Aisheng
> Dong <aisheng.dong@nxp.com>; Abel Vesa <abel.vesa@nxp.com>; linux-
> arm-kernel <linux-arm-kernel@lists.infradead.org>; Linux Kernel Mailing List
> <linux-kernel@vger.kernel.org>; dl-linux-imx <linux-imx@nxp.com>; Daniel
> Baluta <daniel.baluta@nxp.com>
> Subject: Re: [PATCH] soc: imx-scu: Add SoC UID(unique identifier) support
> 
> On Thu, Jun 27, 2019 at 3:48 AM Anson Huang <anson.huang@nxp.com>
> wrote:
> >
> > Hi, Daniel
> >
> > > -----Original Message-----
> > > From: Daniel Baluta <daniel.baluta@gmail.com>
> > > Sent: Wednesday, June 26, 2019 8:42 PM
> > > To: Anson Huang <anson.huang@nxp.com>
> > > Cc: Shawn Guo <shawnguo@kernel.org>; Sascha Hauer
> > > <s.hauer@pengutronix.de>; Pengutronix Kernel Team
> > > <kernel@pengutronix.de>; Fabio Estevam <festevam@gmail.com>;
> Aisheng
> > > Dong <aisheng.dong@nxp.com>; Abel Vesa <abel.vesa@nxp.com>; linux-
> > > arm-kernel <linux-arm-kernel@lists.infradead.org>; Linux Kernel
> > > Mailing List <linux-kernel@vger.kernel.org>; dl-linux-imx
> > > <linux-imx@nxp.com>; Daniel Baluta <daniel.baluta@nxp.com>
> > > Subject: Re: [PATCH] soc: imx-scu: Add SoC UID(unique identifier)
> > > support
> > >
> > > On Wed, Jun 26, 2019 at 10:06 AM <Anson.Huang@nxp.com> wrote:
> > > >
> > > > From: Anson Huang <Anson.Huang@nxp.com>
> > > >
> > > > Add i.MX SCU SoC's UID(unique identifier) support, user can read
> > > > it from sysfs:
> > > >
> > > > root@imx8qxpmek:~# cat /sys/devices/soc0/soc_uid
> > > > 7B64280B57AC1898
> > > >
> > > > Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> > > > ---
> > > >  drivers/soc/imx/soc-imx-scu.c | 35
> > > > +++++++++++++++++++++++++++++++++++
> > > >  1 file changed, 35 insertions(+)
> > > >
> > > > diff --git a/drivers/soc/imx/soc-imx-scu.c
> > > > b/drivers/soc/imx/soc-imx-scu.c index 676f612..8d322a1 100644
> > > > --- a/drivers/soc/imx/soc-imx-scu.c
> > > > +++ b/drivers/soc/imx/soc-imx-scu.c
> > > > @@ -27,6 +27,36 @@ struct imx_sc_msg_misc_get_soc_id {
> > > >         } data;
> > > >  } __packed;
> > > >
> > > > +struct imx_sc_msg_misc_get_soc_uid {
> > > > +       struct imx_sc_rpc_msg hdr;
> > > > +       u32 uid_low;
> > > > +       u32 uid_high;
> > > > +} __packed;
> > > > +
> > > > +static ssize_t soc_uid_show(struct device *dev,
> > > > +                           struct device_attribute *attr, char
> > > > +*buf) {
> > > > +       struct imx_sc_msg_misc_get_soc_uid msg;
> > > > +       struct imx_sc_rpc_msg *hdr = &msg.hdr;
> > > > +       u64 soc_uid;
> > > > +
> > > > +       hdr->ver = IMX_SC_RPC_VERSION;
> > > > +       hdr->svc = IMX_SC_RPC_SVC_MISC;
> > > > +       hdr->func = IMX_SC_MISC_FUNC_UNIQUE_ID;
> > > > +       hdr->size = 1;
> > > > +
> > > > +       /* the return value of SCU FW is in correct, skip return
> > > > + value check */
> > >
> > > Why do you mean by "in correct"?
> >
> > I made a mistake, it should be "incorrect", the existing SCFW of this
> > API returns an error value even this API is successfully called, to
> > make it work with current SCFW, I have to skip the return value check
> > for this API for now. Will send V2 patch to fix this typo.
> 
> Thanks Anson! It makes sense now. It is a little bit sad though because we
> won't know when there is a "real" error :).
> 
> Lets update the comment to be more specific:
> 
> /* SCFW FW API always returns an error even the function is successfully
> executed, so skip returned value */

OK, as for external users, the SCFW formally released has this issue, so for now
I have to skip the return value check for this API, once next SCFW release has this issue
fixed, I will add a patch to check the return value.

Thanks,
Anson.
> 
> 
> > > > +       imx_scu_call_rpc(soc_ipc_handle, &msg, true);
> > > > +
> > > > +       soc_uid = msg.uid_high;
> > > > +       soc_uid <<= 32;
> > > > +       soc_uid |= msg.uid_low;
> > > > +
> > > > +       return sprintf(buf, "%016llX\n", soc_uid);
> > >
> > > snprintf?
> >
> > The snprintf is to avoid buffer overflow, which in this case, I don't
> > know the size of "buf", and the value(u64) to be printed is with fixed
> > length of 64, so I think sprint is just OK.
> 
> Ok.
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [PATCH] soc: imx-scu: Add SoC UID(unique identifier) support
  2019-06-27  7:01       ` Anson Huang
@ 2019-07-02  6:42         ` Marco Felsch
  2019-07-02  7:23           ` Anson Huang
  0 siblings, 1 reply; 7+ messages in thread
From: Marco Felsch @ 2019-07-02  6:42 UTC (permalink / raw)
  To: Anson Huang
  Cc: Aisheng Dong, Daniel Baluta, Fabio Estevam, Abel Vesa,
	Daniel Baluta, Sascha Hauer, Linux Kernel Mailing List,
	dl-linux-imx, Pengutronix Kernel Team, Shawn Guo,
	linux-arm-kernel

Hi Anson,

On 19-06-27 07:01, Anson Huang wrote:
> Hi, Daniel
> 
> > -----Original Message-----
> > From: Daniel Baluta <daniel.baluta@gmail.com>
> > Sent: Thursday, June 27, 2019 2:44 PM
> > To: Anson Huang <anson.huang@nxp.com>
> > Cc: Shawn Guo <shawnguo@kernel.org>; Sascha Hauer
> > <s.hauer@pengutronix.de>; Pengutronix Kernel Team
> > <kernel@pengutronix.de>; Fabio Estevam <festevam@gmail.com>; Aisheng
> > Dong <aisheng.dong@nxp.com>; Abel Vesa <abel.vesa@nxp.com>; linux-
> > arm-kernel <linux-arm-kernel@lists.infradead.org>; Linux Kernel Mailing List
> > <linux-kernel@vger.kernel.org>; dl-linux-imx <linux-imx@nxp.com>; Daniel
> > Baluta <daniel.baluta@nxp.com>
> > Subject: Re: [PATCH] soc: imx-scu: Add SoC UID(unique identifier) support
> > 
> > On Thu, Jun 27, 2019 at 3:48 AM Anson Huang <anson.huang@nxp.com>
> > wrote:
> > >
> > > Hi, Daniel
> > >
> > > > -----Original Message-----
> > > > From: Daniel Baluta <daniel.baluta@gmail.com>
> > > > Sent: Wednesday, June 26, 2019 8:42 PM
> > > > To: Anson Huang <anson.huang@nxp.com>
> > > > Cc: Shawn Guo <shawnguo@kernel.org>; Sascha Hauer
> > > > <s.hauer@pengutronix.de>; Pengutronix Kernel Team
> > > > <kernel@pengutronix.de>; Fabio Estevam <festevam@gmail.com>;
> > Aisheng
> > > > Dong <aisheng.dong@nxp.com>; Abel Vesa <abel.vesa@nxp.com>; linux-
> > > > arm-kernel <linux-arm-kernel@lists.infradead.org>; Linux Kernel
> > > > Mailing List <linux-kernel@vger.kernel.org>; dl-linux-imx
> > > > <linux-imx@nxp.com>; Daniel Baluta <daniel.baluta@nxp.com>
> > > > Subject: Re: [PATCH] soc: imx-scu: Add SoC UID(unique identifier)
> > > > support
> > > >
> > > > On Wed, Jun 26, 2019 at 10:06 AM <Anson.Huang@nxp.com> wrote:
> > > > >
> > > > > From: Anson Huang <Anson.Huang@nxp.com>
> > > > >
> > > > > Add i.MX SCU SoC's UID(unique identifier) support, user can read
> > > > > it from sysfs:
> > > > >
> > > > > root@imx8qxpmek:~# cat /sys/devices/soc0/soc_uid
> > > > > 7B64280B57AC1898
> > > > >
> > > > > Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> > > > > ---
> > > > >  drivers/soc/imx/soc-imx-scu.c | 35
> > > > > +++++++++++++++++++++++++++++++++++
> > > > >  1 file changed, 35 insertions(+)
> > > > >
> > > > > diff --git a/drivers/soc/imx/soc-imx-scu.c
> > > > > b/drivers/soc/imx/soc-imx-scu.c index 676f612..8d322a1 100644
> > > > > --- a/drivers/soc/imx/soc-imx-scu.c
> > > > > +++ b/drivers/soc/imx/soc-imx-scu.c
> > > > > @@ -27,6 +27,36 @@ struct imx_sc_msg_misc_get_soc_id {
> > > > >         } data;
> > > > >  } __packed;
> > > > >
> > > > > +struct imx_sc_msg_misc_get_soc_uid {
> > > > > +       struct imx_sc_rpc_msg hdr;
> > > > > +       u32 uid_low;
> > > > > +       u32 uid_high;
> > > > > +} __packed;
> > > > > +
> > > > > +static ssize_t soc_uid_show(struct device *dev,
> > > > > +                           struct device_attribute *attr, char
> > > > > +*buf) {
> > > > > +       struct imx_sc_msg_misc_get_soc_uid msg;
> > > > > +       struct imx_sc_rpc_msg *hdr = &msg.hdr;
> > > > > +       u64 soc_uid;
> > > > > +
> > > > > +       hdr->ver = IMX_SC_RPC_VERSION;
> > > > > +       hdr->svc = IMX_SC_RPC_SVC_MISC;
> > > > > +       hdr->func = IMX_SC_MISC_FUNC_UNIQUE_ID;
> > > > > +       hdr->size = 1;
> > > > > +
> > > > > +       /* the return value of SCU FW is in correct, skip return
> > > > > + value check */
> > > >
> > > > Why do you mean by "in correct"?
> > >
> > > I made a mistake, it should be "incorrect", the existing SCFW of this
> > > API returns an error value even this API is successfully called, to
> > > make it work with current SCFW, I have to skip the return value check
> > > for this API for now. Will send V2 patch to fix this typo.
> > 
> > Thanks Anson! It makes sense now. It is a little bit sad though because we
> > won't know when there is a "real" error :).
> > 
> > Lets update the comment to be more specific:
> > 
> > /* SCFW FW API always returns an error even the function is successfully
> > executed, so skip returned value */
> 
> OK, as for external users, the SCFW formally released has this issue, so for now
> I have to skip the return value check for this API, once next SCFW release has this issue
> fixed, I will add a patch to check the return value.

Do you really keep track of that? Please can you add a FIXME: or TODO:
tag and add the firmware version containing that bug?

Regards,
  Marco

> Thanks,
> Anson.
> > 
> > 
> > > > > +       imx_scu_call_rpc(soc_ipc_handle, &msg, true);
> > > > > +
> > > > > +       soc_uid = msg.uid_high;
> > > > > +       soc_uid <<= 32;
> > > > > +       soc_uid |= msg.uid_low;
> > > > > +
> > > > > +       return sprintf(buf, "%016llX\n", soc_uid);
> > > >
> > > > snprintf?
> > >
> > > The snprintf is to avoid buffer overflow, which in this case, I don't
> > > know the size of "buf", and the value(u64) to be printed is with fixed
> > > length of 64, so I think sprint is just OK.
> > 
> > Ok.

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
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^ permalink raw reply	[flat|nested] 7+ messages in thread

* RE: [PATCH] soc: imx-scu: Add SoC UID(unique identifier) support
  2019-07-02  6:42         ` Marco Felsch
@ 2019-07-02  7:23           ` Anson Huang
  0 siblings, 0 replies; 7+ messages in thread
From: Anson Huang @ 2019-07-02  7:23 UTC (permalink / raw)
  To: Marco Felsch
  Cc: Aisheng Dong, Daniel Baluta, Fabio Estevam, Abel Vesa,
	Daniel Baluta, Sascha Hauer, Linux Kernel Mailing List,
	dl-linux-imx, Pengutronix Kernel Team, Shawn Guo,
	linux-arm-kernel

Hi, Marco

> Hi Anson,
> 
> On 19-06-27 07:01, Anson Huang wrote:
> > Hi, Daniel
> >
> > > On Thu, Jun 27, 2019 at 3:48 AM Anson Huang <anson.huang@nxp.com>
> > > wrote:
> > > >
> > > > Hi, Daniel
> > > >
> > > > > On Wed, Jun 26, 2019 at 10:06 AM <Anson.Huang@nxp.com> wrote:
> > > > > >
> > > > > > From: Anson Huang <Anson.Huang@nxp.com>
> > > > > >
> > > > > > Add i.MX SCU SoC's UID(unique identifier) support, user can
> > > > > > read it from sysfs:
> > > > > >
> > > > > > root@imx8qxpmek:~# cat /sys/devices/soc0/soc_uid
> > > > > > 7B64280B57AC1898
> > > > > >
> > > > > > Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> > > > > > ---
> > > > > >  drivers/soc/imx/soc-imx-scu.c | 35
> > > > > > +++++++++++++++++++++++++++++++++++
> > > > > >  1 file changed, 35 insertions(+)
> > > > > >
> > > > > > diff --git a/drivers/soc/imx/soc-imx-scu.c
> > > > > > b/drivers/soc/imx/soc-imx-scu.c index 676f612..8d322a1 100644
> > > > > > --- a/drivers/soc/imx/soc-imx-scu.c
> > > > > > +++ b/drivers/soc/imx/soc-imx-scu.c
> > > > > > @@ -27,6 +27,36 @@ struct imx_sc_msg_misc_get_soc_id {
> > > > > >         } data;
> > > > > >  } __packed;
> > > > > >
> > > > > > +struct imx_sc_msg_misc_get_soc_uid {
> > > > > > +       struct imx_sc_rpc_msg hdr;
> > > > > > +       u32 uid_low;
> > > > > > +       u32 uid_high;
> > > > > > +} __packed;
> > > > > > +
> > > > > > +static ssize_t soc_uid_show(struct device *dev,
> > > > > > +                           struct device_attribute *attr,
> > > > > > +char
> > > > > > +*buf) {
> > > > > > +       struct imx_sc_msg_misc_get_soc_uid msg;
> > > > > > +       struct imx_sc_rpc_msg *hdr = &msg.hdr;
> > > > > > +       u64 soc_uid;
> > > > > > +
> > > > > > +       hdr->ver = IMX_SC_RPC_VERSION;
> > > > > > +       hdr->svc = IMX_SC_RPC_SVC_MISC;
> > > > > > +       hdr->func = IMX_SC_MISC_FUNC_UNIQUE_ID;
> > > > > > +       hdr->size = 1;
> > > > > > +
> > > > > > +       /* the return value of SCU FW is in correct, skip
> > > > > > + return value check */
> > > > >
> > > > > Why do you mean by "in correct"?
> > > >
> > > > I made a mistake, it should be "incorrect", the existing SCFW of
> > > > this API returns an error value even this API is successfully
> > > > called, to make it work with current SCFW, I have to skip the
> > > > return value check for this API for now. Will send V2 patch to fix this
> typo.
> > >
> > > Thanks Anson! It makes sense now. It is a little bit sad though
> > > because we won't know when there is a "real" error :).
> > >
> > > Lets update the comment to be more specific:
> > >
> > > /* SCFW FW API always returns an error even the function is
> > > successfully executed, so skip returned value */
> >
> > OK, as for external users, the SCFW formally released has this issue,
> > so for now I have to skip the return value check for this API, once
> > next SCFW release has this issue fixed, I will add a patch to check the return
> value.
> 
> Do you really keep track of that? Please can you add a FIXME: or TODO:
> tag and add the firmware version containing that bug?

Thanks for reminder, I just double checked the SCU FW code, it is actually a mistake, the SCU FW
API of sc_misc_unique_id() is actually a void function, which means it does NOT return anything.
While in our internal kernel tree, we make SCU IPC call to sc_misc_unique_id() with return value
check, and the return value is failure (-5) always. When I clean up the code for upstream, I did NOT notice it.
So the correct comment should be, this API does NOT return anything, no need to check the returned value.
I will fix the comment in next version.

void sc_misc_unique_id(sc_ipc_t ipc, uint32_t *id_l, uint32_t *id_h)

Thanks,
Anson

> 
> Regards,
>   Marco
> 
> > Thanks,
> > Anson.
> > >
> > >
> > > > > > +       imx_scu_call_rpc(soc_ipc_handle, &msg, true);
> > > > > > +
> > > > > > +       soc_uid = msg.uid_high;
> > > > > > +       soc_uid <<= 32;
> > > > > > +       soc_uid |= msg.uid_low;
> > > > > > +
> > > > > > +       return sprintf(buf, "%016llX\n", soc_uid);
> > > > >
> > > > > snprintf?
> > > >
> > > > The snprintf is to avoid buffer overflow, which in this case, I
> > > > don't know the size of "buf", and the value(u64) to be printed is
> > > > with fixed length of 64, so I think sprint is just OK.
> > >
> > > Ok.
> 
> --

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^ permalink raw reply	[flat|nested] 7+ messages in thread

end of thread, other threads:[~2019-07-02  7:23 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-06-26  7:07 [PATCH] soc: imx-scu: Add SoC UID(unique identifier) support Anson.Huang
2019-06-26 12:41 ` Daniel Baluta
2019-06-27  0:48   ` Anson Huang
2019-06-27  6:43     ` Daniel Baluta
2019-06-27  7:01       ` Anson Huang
2019-07-02  6:42         ` Marco Felsch
2019-07-02  7:23           ` Anson Huang

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