On Wed, Sep 25, 2019 at 03:34:47AM +0000, Leo Li wrote: > > > > -----Original Message----- > > From: Biwen Li > > Sent: Tuesday, September 24, 2019 10:30 PM > > To: Leo Li <leoyang...@nxp.com>; shawn...@kernel.org; > > robh...@kernel.org; mark.rutl...@arm.com; Ran Wang > > <ran.wan...@nxp.com> > > Cc: linuxppc-...@lists.ozlabs.org; linux-arm-ker...@lists.infradead.org; > > linux-kernel@vger.kernel.org; devicet...@vger.kernel.org > > Subject: RE: [v3,3/3] Documentation: dt: binding: fsl: Add > > 'fsl,ippdexpcr-alt- > > addr' property > > > > > > > > > > > > > > The 'fsl,ippdexpcr-alt-addr' property is used to handle an > > > > > > errata > > > > > > A-008646 on LS1021A > > > > > > > > > > > > Signed-off-by: Biwen Li <biwen...@nxp.com> > > > > > > --- > > > > > > Change in v3: > > > > > > - rename property name > > > > > > fsl,rcpm-scfg -> fsl,ippdexpcr-alt-addr > > > > > > > > > > > > Change in v2: > > > > > > - update desc of the property 'fsl,rcpm-scfg' > > > > > > > > > > > > Documentation/devicetree/bindings/soc/fsl/rcpm.txt | 14 > > > > > > ++++++++++++++ > > > > > > 1 file changed, 14 insertions(+) > > > > > > > > > > > > diff --git a/Documentation/devicetree/bindings/soc/fsl/rcpm.txt > > > > > > b/Documentation/devicetree/bindings/soc/fsl/rcpm.txt > > > > > > index 5a33619d881d..157dcf6da17c 100644 > > > > > > --- a/Documentation/devicetree/bindings/soc/fsl/rcpm.txt > > > > > > +++ b/Documentation/devicetree/bindings/soc/fsl/rcpm.txt > > > > > > @@ -34,6 +34,11 @@ Chassis Version Example Chips > > > > > > Optional properties: > > > > > > - little-endian : RCPM register block is Little Endian. Without > > > > > > it RCPM > > > > > > will be Big Endian (default case). > > > > > > + - fsl,ippdexpcr-alt-addr : Must add the property for SoC > > > > > > + LS1021A, > > > > > > > > > > You probably should mention this is related to a hardware issue on > > > > > LS1021a and only needed on LS1021a. > > > > Okay, got it, thanks, I will add this in v4. > > > > > > > > > > > + Must include n + 1 entries (n = #fsl,rcpm-wakeup-cells, such as: > > > > > > + #fsl,rcpm-wakeup-cells equal to 2, then must include 2 + 1 > > > > > > entries). > > > > > > > > > > #fsl,rcpm-wakeup-cells is the number of IPPDEXPCR registers on an SoC. > > > > > However you are defining an offset to scfg registers here. Why > > > > > these two are related? The length here should actually be related > > > > > to the #address-cells of the soc/. But since this is only needed > > > > > for LS1021, you can > > > > just make it 3. > > > > I need set the value of IPPDEXPCR resgiters from ftm_alarm0 device > > > > node(fsl,rcpm-wakeup = <&rcpm 0x0 0x20000000>; > > > > 0x0 is a value for IPPDEXPCR0, 0x20000000 is a value for IPPDEXPCR1). > > > > But because of the hardware issue on LS1021A, I need store the value > > > > of IPPDEXPCR registers to an alt address. So I defining an offset to > > > > scfg registers, then RCPM driver get an abosolute address from > > > > offset, RCPM driver write the value of IPPDEXPCR registers to these > > > > abosolute addresses(backup the value of IPPDEXPCR registers). > > > > > > I understand what you are trying to do. The problem is that the new > > > fsl,ippdexpcr-alt-addr property contains a phandle and an offset. The > > > size of it shouldn't be related to #fsl,rcpm-wakeup-cells. > > You maybe like this: fsl,ippdexpcr-alt-addr = <&scfg 0x51c>;/* > > SCFG_SPARECR8 */ > > No. The #address-cell for the soc/ is 2, so the offset to scfg > should be 0x0 0x51c. The total size should be 3, but it shouldn't be > coming from #fsl,rcpm-wakeup-cells like you mentioned in the binding.
Um, no. #address-cells applies to reg and ranges, not some vendor specific property. You can just define how many cells you need if that's fixed. However, I suggested doing this another way in the next version of this. Rob
