Re: [PATCH 1/2] arm64: dts: NS2: Add all of the UARTs

Hi Kefeng,

On 5/12/2016 7:46 AM, Jon Mason wrote:

On Thu, May 12, 2016 at 2:16 AM, Kefeng Wang <wangkefeng.wang@huawei.com
<mailto:wangkefeng.wang@huawei.com>> wrote:



    On 2016/5/12 6:56, Jon Mason wrote:
    > Add all of the UARTs present on NS2 and enable them in the SVK device
    > tree file.  Also, do some magic to make sure that uart3 is discovered as
    > ttyS0 (as that is the console UART).
    >
    > Signed-off-by: Jon Mason <jonmason at broadcom.com <mailto:jonmason@broadcom.com>>
    > ---
    >  arch/arm64/boot/dts/broadcom/ns2-svk.dts | 16 ++++++++++++++++
    >  arch/arm64/boot/dts/broadcom/ns2.dtsi    | 30 ++++++++++++++++++++++++++++++
    >  2 files changed, 46 insertions(+)
    >
    > diff --git a/arch/arm64/boot/dts/broadcom/ns2-svk.dts b/arch/arm64/boot/dts/broadcom/ns2-svk.dts
    > index 7cd3640..b062a44 100644
    > --- a/arch/arm64/boot/dts/broadcom/ns2-svk.dts
    > +++ b/arch/arm64/boot/dts/broadcom/ns2-svk.dts
    > @@ -40,10 +40,14 @@
    >
    >       aliases {
    >               serial0 = &uart3;
    > +             serial1 = &uart0;
    > +             serial2 = &uart1;
    > +             serial3 = &uart2;
    >       };
    >
    >       chosen {
    >               stdout-path = "serial0:115200n8";
    > +             bootargs = "earlycon=uart8250,mmio32,0x66130000";

    Hi Jon,

    I submit a patch[1], with it, we can use earlycon without option to
    enable early console
    for "snps,dw-apb-uart", could you help me to test it, thanks.


Adding your change and removing the line above does not cause earlycon
to work for me.  Is there any additional changes necessary for this to work?

Thanks,
Jon

"OF_EARLYCON_DECLARE" doesn't seem to have a way to deal with DT 
properties? In the case of UART for NS2, it needs mmio32, configured 
with DT property "reg-io-width" set to 4. I don't think 
"OF_EARLYCON_DECLARE" is parsing that, which is likely the reason why it 
doesn't work for devices that required mmio32.

Thanks,

Ray

On 2016/5/13 0:52, Ray Jui wrote:

Hi Kefeng,

On 5/12/2016 7:46 AM, Jon Mason wrote:

quoted

On Thu, May 12, 2016 at 2:16 AM, Kefeng Wang <wangkefeng.wang@huawei.com
<mailto:wangkefeng.wang@huawei.com>> wrote:



    On 2016/5/12 6:56, Jon Mason wrote:
    > Add all of the UARTs present on NS2 and enable them in the SVK device
    > tree file.  Also, do some magic to make sure that uart3 is discovered as
    > ttyS0 (as that is the console UART).
    >
    > Signed-off-by: Jon Mason <jonmason at broadcom.com <mailto:jonmason@broadcom.com>>
    > ---
    >  arch/arm64/boot/dts/broadcom/ns2-svk.dts | 16 ++++++++++++++++
    >  arch/arm64/boot/dts/broadcom/ns2.dtsi    | 30 ++++++++++++++++++++++++++++++
    >  2 files changed, 46 insertions(+)
    >
    > diff --git a/arch/arm64/boot/dts/broadcom/ns2-svk.dts b/arch/arm64/boot/dts/broadcom/ns2-svk.dts
    > index 7cd3640..b062a44 100644
    > --- a/arch/arm64/boot/dts/broadcom/ns2-svk.dts
    > +++ b/arch/arm64/boot/dts/broadcom/ns2-svk.dts
    > @@ -40,10 +40,14 @@
    >
    >       aliases {
    >               serial0 = &uart3;
    > +             serial1 = &uart0;
    > +             serial2 = &uart1;
    > +             serial3 = &uart2;
    >       };
    >
    >       chosen {
    >               stdout-path = "serial0:115200n8";
    > +             bootargs = "earlycon=uart8250,mmio32,0x66130000";

    Hi Jon,

    I submit a patch[1], with it, we can use earlycon without option to
    enable early console
    for "snps,dw-apb-uart", could you help me to test it, thanks.


Adding your change and removing the line above does not cause earlycon
to work for me.  Is there any additional changes necessary for this to work?

Thanks,
Jon

"OF_EARLYCON_DECLARE" doesn't seem to have a way to deal with DT properties? In the case of UART for NS2, it needs mmio32, configured with DT property "reg-io-width" set to 4. I don't think "OF_EARLYCON_DECLARE" is parsing that, which is likely the reason why it doesn't work for devices that required mmio32.

It should work, I test this in Hisi D02 board, it uses same uart and same configuration.

early_init_dt_scan_chosen_serial()
 for (match = __earlycon_table; match < __earlycon_table_end; match++)
 	......
	of_setup_earlycon()
		val = of_get_flat_dt_prop(node, "reg-io-width", NULL);  // will obtain the reg-io-width and set iotype=mmio32
		err = match->setup(&early_console_dev, options);  // call early_serial8250_setup

Could you check it again, thanks,

Kefeng

Thanks,

Ray

.