From: Anson Huang <[email protected]>
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 <[email protected]>
---
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
On Wed, Jun 26, 2019 at 10:06 AM <[email protected]> wrote:
>
> From: Anson Huang <[email protected]>
>
> 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 <[email protected]>
> ---
> 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
>
Hi, Daniel
> -----Original Message-----
> From: Daniel Baluta <[email protected]>
> Sent: Wednesday, June 26, 2019 8:42 PM
> To: Anson Huang <[email protected]>
> Cc: Shawn Guo <[email protected]>; Sascha Hauer
> <[email protected]>; Pengutronix Kernel Team
> <[email protected]>; Fabio Estevam <[email protected]>; Aisheng
> Dong <[email protected]>; Abel Vesa <[email protected]>; linux-
> arm-kernel <[email protected]>; Linux Kernel Mailing List
> <[email protected]>; dl-linux-imx <[email protected]>; Daniel
> Baluta <[email protected]>
> Subject: Re: [PATCH] soc: imx-scu: Add SoC UID(unique identifier) support
>
> On Wed, Jun 26, 2019 at 10:06 AM <[email protected]> wrote:
> >
> > From: Anson Huang <[email protected]>
> >
> > 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 <[email protected]>
> > ---
> > 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
> >
On Thu, Jun 27, 2019 at 3:48 AM Anson Huang <[email protected]> wrote:
>
> Hi, Daniel
>
> > -----Original Message-----
> > From: Daniel Baluta <[email protected]>
> > Sent: Wednesday, June 26, 2019 8:42 PM
> > To: Anson Huang <[email protected]>
> > Cc: Shawn Guo <[email protected]>; Sascha Hauer
> > <[email protected]>; Pengutronix Kernel Team
> > <[email protected]>; Fabio Estevam <[email protected]>; Aisheng
> > Dong <[email protected]>; Abel Vesa <[email protected]>; linux-
> > arm-kernel <[email protected]>; Linux Kernel Mailing List
> > <[email protected]>; dl-linux-imx <[email protected]>; Daniel
> > Baluta <[email protected]>
> > Subject: Re: [PATCH] soc: imx-scu: Add SoC UID(unique identifier) support
> >
> > On Wed, Jun 26, 2019 at 10:06 AM <[email protected]> wrote:
> > >
> > > From: Anson Huang <[email protected]>
> > >
> > > 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 <[email protected]>
> > > ---
> > > 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.
Hi, Daniel
> -----Original Message-----
> From: Daniel Baluta <[email protected]>
> Sent: Thursday, June 27, 2019 2:44 PM
> To: Anson Huang <[email protected]>
> Cc: Shawn Guo <[email protected]>; Sascha Hauer
> <[email protected]>; Pengutronix Kernel Team
> <[email protected]>; Fabio Estevam <[email protected]>; Aisheng
> Dong <[email protected]>; Abel Vesa <[email protected]>; linux-
> arm-kernel <[email protected]>; Linux Kernel Mailing List
> <[email protected]>; dl-linux-imx <[email protected]>; Daniel
> Baluta <[email protected]>
> Subject: Re: [PATCH] soc: imx-scu: Add SoC UID(unique identifier) support
>
> On Thu, Jun 27, 2019 at 3:48 AM Anson Huang <[email protected]>
> wrote:
> >
> > Hi, Daniel
> >
> > > -----Original Message-----
> > > From: Daniel Baluta <[email protected]>
> > > Sent: Wednesday, June 26, 2019 8:42 PM
> > > To: Anson Huang <[email protected]>
> > > Cc: Shawn Guo <[email protected]>; Sascha Hauer
> > > <[email protected]>; Pengutronix Kernel Team
> > > <[email protected]>; Fabio Estevam <[email protected]>;
> Aisheng
> > > Dong <[email protected]>; Abel Vesa <[email protected]>; linux-
> > > arm-kernel <[email protected]>; Linux Kernel
> > > Mailing List <[email protected]>; dl-linux-imx
> > > <[email protected]>; Daniel Baluta <[email protected]>
> > > Subject: Re: [PATCH] soc: imx-scu: Add SoC UID(unique identifier)
> > > support
> > >
> > > On Wed, Jun 26, 2019 at 10:06 AM <[email protected]> wrote:
> > > >
> > > > From: Anson Huang <[email protected]>
> > > >
> > > > 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 <[email protected]>
> > > > ---
> > > > 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.
Hi Anson,
On 19-06-27 07:01, Anson Huang wrote:
> Hi, Daniel
>
> > -----Original Message-----
> > From: Daniel Baluta <[email protected]>
> > Sent: Thursday, June 27, 2019 2:44 PM
> > To: Anson Huang <[email protected]>
> > Cc: Shawn Guo <[email protected]>; Sascha Hauer
> > <[email protected]>; Pengutronix Kernel Team
> > <[email protected]>; Fabio Estevam <[email protected]>; Aisheng
> > Dong <[email protected]>; Abel Vesa <[email protected]>; linux-
> > arm-kernel <[email protected]>; Linux Kernel Mailing List
> > <[email protected]>; dl-linux-imx <[email protected]>; Daniel
> > Baluta <[email protected]>
> > Subject: Re: [PATCH] soc: imx-scu: Add SoC UID(unique identifier) support
> >
> > On Thu, Jun 27, 2019 at 3:48 AM Anson Huang <[email protected]>
> > wrote:
> > >
> > > Hi, Daniel
> > >
> > > > -----Original Message-----
> > > > From: Daniel Baluta <[email protected]>
> > > > Sent: Wednesday, June 26, 2019 8:42 PM
> > > > To: Anson Huang <[email protected]>
> > > > Cc: Shawn Guo <[email protected]>; Sascha Hauer
> > > > <[email protected]>; Pengutronix Kernel Team
> > > > <[email protected]>; Fabio Estevam <[email protected]>;
> > Aisheng
> > > > Dong <[email protected]>; Abel Vesa <[email protected]>; linux-
> > > > arm-kernel <[email protected]>; Linux Kernel
> > > > Mailing List <[email protected]>; dl-linux-imx
> > > > <[email protected]>; Daniel Baluta <[email protected]>
> > > > Subject: Re: [PATCH] soc: imx-scu: Add SoC UID(unique identifier)
> > > > support
> > > >
> > > > On Wed, Jun 26, 2019 at 10:06 AM <[email protected]> wrote:
> > > > >
> > > > > From: Anson Huang <[email protected]>
> > > > >
> > > > > 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 <[email protected]>
> > > > > ---
> > > > > 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 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
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 <[email protected]>
> > > wrote:
> > > >
> > > > Hi, Daniel
> > > >
> > > > > On Wed, Jun 26, 2019 at 10:06 AM <[email protected]> wrote:
> > > > > >
> > > > > > From: Anson Huang <[email protected]>
> > > > > >
> > > > > > 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 <[email protected]>
> > > > > > ---
> > > > > > 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.
>
> --