| Message ID | 1457380318-15452-5-git-send-email-fcooper@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Mar 07, 2016 at 01:51:57PM -0600, Franklin S Cooper Jr wrote: > Since the PWMSS and its subdevices (eCAP and ePWM) use the same address > space then the range property should be empty. Update the documentation > to show the correct usage. Why does it matter? An empty ranges is generally not preferred. > > Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com> > --- > Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt | 12 ++++-------- > 1 file changed, 4 insertions(+), 8 deletions(-) > > diff --git a/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt b/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt > index f7eae77..672fa71 100644 > --- a/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt > +++ b/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt > @@ -7,11 +7,9 @@ Required properties: > Should set to 1. > - size-cells: specify number of u32 entries needed to specify child nodes size > in reg property. Should set to 1. > -- ranges: describes the address mapping of a memory-mapped bus. Should set to > - physical address map of child's base address, physical address within > - parent's address space and length of the address map. For am33xx, > - 3 set of child register maps present, ECAP register space, EQEP > - register space, EHRPWM register space. > +- ranges: describes the address mapping of a memory-mapped bus. Its value > + should be empty since no address translation is needed between the > + parent and the child. > > Also child nodes should also populated under PWMSS DT node. > > @@ -23,9 +21,7 @@ pwmss0: pwmss@48300000 { > #address-cells = <1>; > #size-cells = <1>; > status = "disabled"; > - ranges = <0x48300100 0x48300100 0x80 /* ECAP */ > - 0x48300180 0x48300180 0x80 /* EQEP */ > - 0x48300200 0x48300200 0x80>; /* EHRPWM */ > + ranges; > > /* child nodes go here */ > }; > -- > 2.7.0 >
On 03/17/2016 10:01 AM, Rob Herring wrote: > On Mon, Mar 07, 2016 at 01:51:57PM -0600, Franklin S Cooper Jr wrote: >> Since the PWMSS and its subdevices (eCAP and ePWM) use the same address >> space then the range property should be empty. Update the documentation >> to show the correct usage. > Why does it matter? An empty ranges is generally not preferred. Someone pointed out that ranges should probably be empty. I double checked it with what is in the ePAPR doc and based on the definition it should be set to empty. I also checked against the am33xx.dtsi and saw that both USB and ethernet uses an empty value for ranges. Can you elaborate on why this isn't preferable? > >> Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com> >> --- >> Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt | 12 ++++-------- >> 1 file changed, 4 insertions(+), 8 deletions(-) >> >> diff --git a/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt b/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt >> index f7eae77..672fa71 100644 >> --- a/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt >> +++ b/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt >> @@ -7,11 +7,9 @@ Required properties: >> Should set to 1. >> - size-cells: specify number of u32 entries needed to specify child nodes size >> in reg property. Should set to 1. >> -- ranges: describes the address mapping of a memory-mapped bus. Should set to >> - physical address map of child's base address, physical address within >> - parent's address space and length of the address map. For am33xx, >> - 3 set of child register maps present, ECAP register space, EQEP >> - register space, EHRPWM register space. >> +- ranges: describes the address mapping of a memory-mapped bus. Its value >> + should be empty since no address translation is needed between the >> + parent and the child. >> >> Also child nodes should also populated under PWMSS DT node. >> >> @@ -23,9 +21,7 @@ pwmss0: pwmss@48300000 { >> #address-cells = <1>; >> #size-cells = <1>; >> status = "disabled"; >> - ranges = <0x48300100 0x48300100 0x80 /* ECAP */ >> - 0x48300180 0x48300180 0x80 /* EQEP */ >> - 0x48300200 0x48300200 0x80>; /* EHRPWM */ >> + ranges; >> >> /* child nodes go here */ >> }; >> -- >> 2.7.0 >>
On 03/17/2016 11:56 AM, Franklin S Cooper Jr. wrote: > > On 03/17/2016 10:01 AM, Rob Herring wrote: >> On Mon, Mar 07, 2016 at 01:51:57PM -0600, Franklin S Cooper Jr wrote: >>> Since the PWMSS and its subdevices (eCAP and ePWM) use the same address >>> space then the range property should be empty. Update the documentation >>> to show the correct usage. >> Why does it matter? An empty ranges is generally not preferred. > Someone pointed out that ranges should probably be empty. I > double checked it with what is in the ePAPR doc and based on > the definition it should be set to empty. I also checked > against the am33xx.dtsi and saw that both USB and ethernet > uses an empty value for ranges. > > Can you elaborate on why this isn't preferable? I'm going to drop this patch and the previous patch for now that messes with the ranges property. I can resubmit them separately later on if that is the route we decide to take. > >>> Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com> >>> --- >>> Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt | 12 ++++-------- >>> 1 file changed, 4 insertions(+), 8 deletions(-) >>> >>> diff --git a/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt b/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt >>> index f7eae77..672fa71 100644 >>> --- a/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt >>> +++ b/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt >>> @@ -7,11 +7,9 @@ Required properties: >>> Should set to 1. >>> - size-cells: specify number of u32 entries needed to specify child nodes size >>> in reg property. Should set to 1. >>> -- ranges: describes the address mapping of a memory-mapped bus. Should set to >>> - physical address map of child's base address, physical address within >>> - parent's address space and length of the address map. For am33xx, >>> - 3 set of child register maps present, ECAP register space, EQEP >>> - register space, EHRPWM register space. >>> +- ranges: describes the address mapping of a memory-mapped bus. Its value >>> + should be empty since no address translation is needed between the >>> + parent and the child. >>> >>> Also child nodes should also populated under PWMSS DT node. >>> >>> @@ -23,9 +21,7 @@ pwmss0: pwmss@48300000 { >>> #address-cells = <1>; >>> #size-cells = <1>; >>> status = "disabled"; >>> - ranges = <0x48300100 0x48300100 0x80 /* ECAP */ >>> - 0x48300180 0x48300180 0x80 /* EQEP */ >>> - 0x48300200 0x48300200 0x80>; /* EHRPWM */ >>> + ranges; >>> >>> /* child nodes go here */ >>> }; >>> -- >>> 2.7.0 >>> > -- > To unsubscribe from this list: send the line "unsubscribe linux-omap" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt b/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt index f7eae77..672fa71 100644 --- a/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt +++ b/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt @@ -7,11 +7,9 @@ Required properties: Should set to 1. - size-cells: specify number of u32 entries needed to specify child nodes size in reg property. Should set to 1. -- ranges: describes the address mapping of a memory-mapped bus. Should set to - physical address map of child's base address, physical address within - parent's address space and length of the address map. For am33xx, - 3 set of child register maps present, ECAP register space, EQEP - register space, EHRPWM register space. +- ranges: describes the address mapping of a memory-mapped bus. Its value + should be empty since no address translation is needed between the + parent and the child. Also child nodes should also populated under PWMSS DT node. @@ -23,9 +21,7 @@ pwmss0: pwmss@48300000 { #address-cells = <1>; #size-cells = <1>; status = "disabled"; - ranges = <0x48300100 0x48300100 0x80 /* ECAP */ - 0x48300180 0x48300180 0x80 /* EQEP */ - 0x48300200 0x48300200 0x80>; /* EHRPWM */ + ranges; /* child nodes go here */ };
Since the PWMSS and its subdevices (eCAP and ePWM) use the same address space then the range property should be empty. Update the documentation to show the correct usage. Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com> --- Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-)