RE: [PATCH v2 2/2] arm64: dts: imx93: specify available 'ngpios' per GPIO port

[Bough Chen <haibo.chen@xxxxxxx>]

> -----Original Message-----
> From: Hector Palacios <hector.palacios@xxxxxxxx>
> Sent: 2024年1月15日 23:42
> To: Alexander Stein <alexander.stein@xxxxxxxxxxxxxxx>;
> linus.walleij@xxxxxxxxxx; brgl@xxxxxxxx; robh+dt@xxxxxxxxxx
> Cc: stefan@xxxxxxxx; linux-gpio@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx;
> Peng Fan <peng.fan@xxxxxxx>; Bough Chen <haibo.chen@xxxxxxx>
> Subject: Re: [PATCH v2 2/2] arm64: dts: imx93: specify available 'ngpios' per
> GPIO port
> 
> Hi Alexander,
> 
> On 1/15/24 14:30, Alexander Stein wrote:
> > Hi Hector,
> >
> > thanks for the patch.
> >
> > Am Montag, 15. Januar 2024, 14:16:05 CET schrieb Hector Palacios:
> >> According to NXP HRM for i.MX93, the following GPIO pins are available:
> >> - GPIO1: 16 pins (0..15)
> >
> > Mh, RM Rev4 (12/2023) says:
> >>   Bit[31:17] should be Reserved for GPIO1
> >
> > So GPIO1 has the range 0..16
> >
> >> - GPIO2: 30 pins (0..29)
> >> - GPIO3: 32 pins (0..31)
> >> - GPIO4: 30 pins (0..29)
> >
> > RM Rev4 (12/2023) says:
> >> Bit[31:28] should be Reserved for GPIO4
> >
> > So GPIO4 would be the range 0..27
> >
> > Where did you get your numbers from?
> 
> I also saw what you point out about the HRM but when cross-checking with the
> IOMUXC topic (Chapter 27) to verify what pads can work as GPIO for each of the
> ports, I found you can configure pads for
> - GPIO1_IO00..GPIO1_IO15
> - GPIO2_IO00..GPIO2_IO29
> - GPIO3_IO00..GPIO3_IO31
> - GPIO4_IO00..GPIO4_IO29
> 
> which doesn't exactly match the note about the reserved bits.
> I consider the IOMUXC topic more reliable but it would definitely be better if
> someone from NXP could clarify.

Hi All,

I just confirm with IP team, they use the IOMUX to implement RTL code. So IOMUX is reliable.
The following are correct.
 - GPIO1_IO00..GPIO1_IO15
 - GPIO2_IO00..GPIO2_IO29
 - GPIO3_IO00..GPIO3_IO31
 - GPIO4_IO00..GPIO4_IO29

I will ask the Doc team to update the reserved bits to align with the IOMUX.

Best Regards
Haibo Chen
> 
> Regards
> --
> Héctor Palacios
> 
> >
> >>
> >> Signed-off-by: Hector Palacios <hector.palacios@xxxxxxxx>
> >> ---
> >>   arch/arm64/boot/dts/freescale/imx93.dtsi | 4 ++++
> >>   1 file changed, 4 insertions(+)
> >>
> >> diff --git a/arch/arm64/boot/dts/freescale/imx93.dtsi
> >> b/arch/arm64/boot/dts/freescale/imx93.dtsi index
> >> 34c0540276d1..7eb2cab7c749
> >> 100644
> >> --- a/arch/arm64/boot/dts/freescale/imx93.dtsi
> >> +++ b/arch/arm64/boot/dts/freescale/imx93.dtsi
> >> @@ -970,6 +970,7 @@ gpio2: gpio@43810000 {
> >>                                 <&clk IMX93_CLK_GPIO2_GATE>;
> >>                        clock-names = "gpio", "port";
> >>                        gpio-ranges = <&iomuxc 0 4 30>;
> >> +                     ngpios = <30>;
> >>                };
> >>
> >>                gpio3: gpio@43820000 { @@ -986,6 +987,7 @@ gpio3:
> >> gpio@43820000 {
> >>                        clock-names = "gpio", "port";
> >>                        gpio-ranges = <&iomuxc 0 84 8>, <&iomuxc 8
> 66
> > 18>,
> >>                                      <&iomuxc 26 34 2>,
> <&iomuxc 28 0
> > 4>;
> >> +                     ngpios = <32>;
> >>                };
> >>
> >>                gpio4: gpio@43830000 { @@ -1001,6 +1003,7 @@
> gpio4:
> >> gpio@43830000 {
> >>                                 <&clk IMX93_CLK_GPIO4_GATE>;
> >>                        clock-names = "gpio", "port";
> >>                        gpio-ranges = <&iomuxc 0 38 28>, <&iomuxc 28
> >> 36
> > 2>;
> >> +                     ngpios = <30>;
> >>                };
> >>
> >>                gpio1: gpio@47400000 { @@ -1016,6 +1019,7 @@
> gpio1:
> >> gpio@47400000 {
> >>                                 <&clk IMX93_CLK_GPIO1_GATE>;
> >>                        clock-names = "gpio", "port";
> >>                        gpio-ranges = <&iomuxc 0 92 16>;
> >> +                     ngpios = <16>;
> >>                };
> >>
> >>                ocotp: efuse@47510000 {
> >