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 ? -- viresh