Hi Leo
Tuesday, September 22, 2020 6:43 AM, Leo Li wrote:
>
>
> > -----Original Message-----
> > From: Ran Wang <ran.wang_1@xxxxxxx>
> > Sent: Wednesday, September 16, 2020 3:18 AM
> > To: Leo Li <leoyang.li@xxxxxxx>; Rob Herring <robh+dt@xxxxxxxxxx>;
> > Shawn Guo <shawnguo@xxxxxxxxxx>
> > Cc: linuxppc-dev@xxxxxxxxxxxxxxxx;
> > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx;
> > devicetree@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Biwen Li
> > <biwen.li@xxxxxxx>; Ran Wang <ran.wang_1@xxxxxxx>
> > Subject: [PATCH 2/5] soc: fsl: handle RCPM errata A-008646 on SoC
> > LS1021A
> >
> > From: Biwen Li <biwen.li@xxxxxxx>
> >
> > Description:
> > - Reading configuration register RCPM_IPPDEXPCR1
> > always return zero
> >
> > Workaround:
> > - Save register RCPM_IPPDEXPCR1's value to
> > register SCFG_SPARECR8.(uboot's psci also
> > need reading value from the register SCFG_SPARECR8
> > to set register RCPM_IPPDEXPCR1)
> >
> > Impact:
> > - FlexTimer module will cannot wakeup system in
> Will not..
> Also it will be better to merge this with the issue description part above to
> prevent confusion.
OK
> > deep sleep on SoC LS1021A
> >
> > Signed-off-by: Biwen Li <biwen.li@xxxxxxx>
> > Signed-off-by: Ran Wang <ran.wang_1@xxxxxxx>
> > ---
> > drivers/soc/fsl/rcpm.c | 42
> > +++++++++++++++++++++++++++++++++++++++++-
> > 1 file changed, 41 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/soc/fsl/rcpm.c b/drivers/soc/fsl/rcpm.c index
> > a093dbe..e6354f5 100644
> > --- a/drivers/soc/fsl/rcpm.c
> > +++ b/drivers/soc/fsl/rcpm.c
> > @@ -2,7 +2,7 @@
> > //
> > // rcpm.c - Freescale QorIQ RCPM driver // -// Copyright 2019 NXP
> > +// Copyright 2019-2020 NXP
> > //
> > // Author: Ran Wang <ran.wang_1@xxxxxxx>
> >
> > @@ -13,6 +13,9 @@
> > #include <linux/slab.h>
> > #include <linux/suspend.h>
> > #include <linux/kernel.h>
> > +#include <linux/acpi.h>
> > +#include <linux/mfd/syscon.h>
> > +#include <linux/regmap.h>
> >
> > #define RCPM_WAKEUP_CELL_MAX_SIZE 7
> >
> > @@ -37,6 +40,9 @@ static int rcpm_pm_prepare(struct device *dev)
> > struct device_node *np = dev->of_node;
> > u32 value[RCPM_WAKEUP_CELL_MAX_SIZE + 1];
> > u32 setting[RCPM_WAKEUP_CELL_MAX_SIZE] = {0};
> > + struct regmap *scfg_addr_regmap = NULL;
> > + u32 reg_offset[2];
> > + u32 reg_value = 0;
> >
> > rcpm = dev_get_drvdata(dev);
> > if (!rcpm)
> > @@ -90,6 +96,40 @@ static int rcpm_pm_prepare(struct device *dev)
> > tmp |= ioread32be(address);
> > iowrite32be(tmp, address);
> > }
> > + /*
> > + * Workaround of errata A-008646 on SoC LS1021A:
> > + * There is a bug of register ippdexpcr1.
> > + * Reading configuration register RCPM_IPPDEXPCR1
> > + * always return zero. So save ippdexpcr1's value
> > + * to register SCFG_SPARECR8.And the value of
> > + * ippdexpcr1 will be read from SCFG_SPARECR8.
> > + */
> > + if (device_property_present(dev, "fsl,ippdexpcr1-alt-addr"))
> > {
> > + if (dev_of_node(dev)) {
> > + scfg_addr_regmap =
> > syscon_regmap_lookup_by_phandle(np,
> > +
> > "fsl,ippdexpcr1-alt-addr");
> > + } else if (is_acpi_node(dev->fwnode)) {
> > + continue;
> > + }
> > +
> > + if (scfg_addr_regmap && (i == 1)) {
> > + if (device_property_read_u32_array(dev,
> > + "fsl,ippdexpcr1-alt-addr",
> > + reg_offset,
> > + 2)) {
>
> It is not necessary to read out the whole fsl,ippdexpcr1-alt-addr property if we
> only need the offset. Also you can change to use the
> syscon_regmap_lookup_by_phandle_args() API above to simplify the code.
Got it, will update it in next version, thanks.
Regards,
Ran
> > + scfg_addr_regmap = NULL;
> > + continue;
> > + }
> > + /* Read value from register SCFG_SPARECR8
> > */
> > + regmap_read(scfg_addr_regmap,
> > + reg_offset[1],
> > + ®_value);
> > + /* Write value to register SCFG_SPARECR8 */
> > + regmap_write(scfg_addr_regmap,
> > + reg_offset[1],
> > + tmp | reg_value);
> > + }
> > + }
> > }
> >
> > return 0;
> > --
> > 2.7.4
