Hi, Viresh
Anson Huang
Best Regards!
> -----Original Message-----
> From: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
> Sent: Monday, October 1, 2018 1:58 PM
> To: Anson Huang <anson.huang@xxxxxxx>
> Cc: shawnguo@xxxxxxxxxx; s.hauer@xxxxxxxxxxxxxx; kernel@xxxxxxxxxxxxxx;
> Fabio Estevam <fabio.estevam@xxxxxxx>; robh+dt@xxxxxxxxxx;
> mark.rutland@xxxxxxx; rjw@xxxxxxxxxxxxx;
> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx; linux-pm@xxxxxxxxxxxxxxx; dl-linux-imx
> <linux-imx@xxxxxxx>
> Subject: Re: [PATCH V2 2/2] cpufreq: imx6q: read OCOTP through nvmem for
> imx6ul/imx6ull
>
> On 17-09-18, 11:17, Anson Huang wrote:
> > On i.MX6UL/i.MX6ULL, accessing OCOTP directly is wrong because the
> > ocotp clock needs to be enabled first. Add support for reading OCOTP
> > through the nvmem API, and keep the old method there to support old
> > dtb.
> >
> > Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
> > ---
> > changes since V1:
> > add old dtb support.
> > drivers/cpufreq/imx6q-cpufreq.c | 52
> > +++++++++++++++++++++++++++--------------
> > 1 file changed, 35 insertions(+), 17 deletions(-)
> >
> > diff --git a/drivers/cpufreq/imx6q-cpufreq.c
> > b/drivers/cpufreq/imx6q-cpufreq.c index b2ff423..518386c4 100644
> > --- a/drivers/cpufreq/imx6q-cpufreq.c
> > +++ b/drivers/cpufreq/imx6q-cpufreq.c
> > @@ -12,6 +12,7 @@
> > #include <linux/cpu_cooling.h>
> > #include <linux/err.h>
> > #include <linux/module.h>
> > +#include <linux/nvmem-consumer.h>
> > #include <linux/of.h>
> > #include <linux/of_address.h>
> > #include <linux/pm_opp.h>
> > @@ -290,20 +291,32 @@ static void
> imx6q_opp_check_speed_grading(struct device *dev)
> > #define OCOTP_CFG3_6ULL_SPEED_792MHZ 0x2
> > #define OCOTP_CFG3_6ULL_SPEED_900MHZ 0x3
> >
> > -static void imx6ul_opp_check_speed_grading(struct device *dev)
> > +static int imx6ul_opp_check_speed_grading(struct device *dev)
> > {
> > - struct device_node *np;
> > - void __iomem *base;
> > u32 val;
> > + int ret = 0;
> >
> > - np = of_find_compatible_node(NULL, NULL, "fsl,imx6ul-ocotp");
> > - if (!np)
> > - return;
> > + if (of_find_property(dev->of_node, "nvmem-cells", NULL)) {
> > + ret = nvmem_cell_read_u32(dev, "speed_grade", &val);
> > + if (ret)
> > + return ret;
> > + } else {
> > + struct device_node *np;
> > + void __iomem *base;
> > +
> > + np = of_find_compatible_node(NULL, NULL, "fsl,imx6ul-ocotp");
> > + if (!np)
> > + return -ENOENT;
> > +
> > + base = of_iomap(np, 0);
> > + if (!base) {
> > + dev_err(dev, "failed to map ocotp\n");
> > + of_node_put(np);
> > + return -EFAULT;
> > + }
> >
> > - base = of_iomap(np, 0);
> > - if (!base) {
> > - dev_err(dev, "failed to map ocotp\n");
> > - goto put_node;
> > + val = readl_relaxed(base + OCOTP_CFG3);
> > + iounmap(base);
>
> Don't you need to put the node np here ?
Correct, I should put the node here as well, please help review V3 patch, thanks.
Anson.
>
> --
> viresh
