Hi Aisheng,
> Subject: RE: [PATCH 2/4] nvmem: imx: add i.MX8 nvmem driver
>
> > From: Peng Fan
> > Sent: Sunday, May 5, 2019 9:28 PM
> > Subject: [PATCH 2/4] nvmem: imx: add i.MX8 nvmem driver
> >
> > This patch adds i.MX8 nvmem ocotp driver to access fuse via RPC to
> > i.MX8 system controller.
> >
> > Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
>
> Only a few minor comments.
> Otherwise, this patch looks good to me.
>
> First, the patch title probably better to be:
> nvmem: imx: add i.MX8 SCU based ocotp driver support
Fix in V2.
>
> > Cc: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
> > Cc: Shawn Guo <shawnguo@xxxxxxxxxx>
> > Cc: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
> > Cc: Pengutronix Kernel Team <kernel@xxxxxxxxxxxxxx>
> > Cc: Fabio Estevam <festevam@xxxxxxxxx>
> > Cc: NXP Linux Team <linux-imx@xxxxxxx>
> > Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> > ---
> > drivers/nvmem/Kconfig | 7 +++
> > drivers/nvmem/Makefile | 2 +
> > drivers/nvmem/imx-ocotp-scu.c | 135
> > ++++++++++++++++++++++++++++++++++++++++++
> > 3 files changed, 144 insertions(+)
> > create mode 100644 drivers/nvmem/imx-ocotp-scu.c
> >
> > diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig index
> > 530d570724c9..0e705c04bd8c 100644
> > --- a/drivers/nvmem/Kconfig
> > +++ b/drivers/nvmem/Kconfig
> > @@ -36,6 +36,13 @@ config NVMEM_IMX_OCOTP
> > This driver can also be built as a module. If so, the module
> > will be called nvmem-imx-ocotp.
> >
> > +config NVMEM_IMX_OCOTP_SCU
> > + tristate "i.MX8 On-Chip OTP Controller support"
>
> i.MX8 SCU On-Chip OTP Controller support
Fix in V2
>
> > + depends on IMX_SCU
> > + help
> > + This is a driver for the On-Chip OTP Controller (OCOTP)
>
> SCU On-Chip OTP
Fix in V2.
>
> > + available on i.MX8 SoCs.
> > +
[.....]
> > +
> > +static int imx_scu_ocotp_read(void *context, unsigned int offset,
> > + void *val, size_t bytes)
> > +{
> > + struct ocotp_priv *priv = context;
> > + u32 count, index, num_bytes;
> > + u8 *buf, *p;
>
> It seems buf has never been used as u8.
> So probably a better way is:
> U32 *buf;
> Void *p.
> Then we can save all the explicit conversion of u32.
Fix in V2.
>
> > + int i, ret;
> > +
> > + index = offset >> 2;
> > + num_bytes = round_up((offset % 4) + bytes, 4);
> > + count = num_bytes >> 2;
> > +
> > + if (count > (priv->data->nregs - index))
> > + count = priv->data->nregs - index;
> > +
> > + p = kzalloc(num_bytes, GFP_KERNEL);
> > + if (!p)
> > + return -ENOMEM;
> > +
> > + buf = p;
> > +
> > + for (i = index; i < (index + count); i++) {
> > + if (priv->data->devtype == IMX8QXP) {
> > + if ((i > 271) && (i < 544)) {
> > + *(u32 *)buf = 0;
> > + buf += 4;
> > + continue;
> > + }
> > + }
> > +
> > + ret = imx_sc_misc_otp_fuse_read(priv->nvmem_ipc, i,
> > + (u32 *)buf);
>
> Is this API already in kernel?
Ah. I forgot to post out that API in this patchset. Will add that in V2.
[....]
> > +
> > +MODULE_AUTHOR("Peng Fan <peng.fan@xxxxxxx>");
> > +MODULE_DESCRIPTION("i.MX8QM OCOTP fuse box driver");
>
> i.MX8 SCU OCOTP fuse box driver
Fix in V2.
Thanks,
Peng.
>
> Regards
> Dong Aisheng
>
> > +MODULE_LICENSE("GPL v2");
> > --
> > 2.16.4
