On Fri, Jul 3, 2020 at 7:34 PM Jagan Teki <ja...@amarulasolutions.com> wrote:
>
> On Fri, Jul 3, 2020 at 6:09 PM Robin Murphy <robin.mur...@arm.com> wrote:
> >
> > On 2020-07-03 11:10, Jagan Teki wrote:
> > > On Thu, Jul 2, 2020 at 7:26 PM Robin Murphy <robin.mur...@arm.com> wrote:
> > >>
> > >> On 2020-07-02 09:48, Jagan Teki wrote:
> > >>> The new rk3288 revision rk3288w has some changes with respect
> > >>> to legacy rk3288 like hclk_vio and usb host0 ohci.
> > >>>
> > >>> In order to work these on the same in Linux kernel update the
> > >>> compatible the root compatible with rockchip,rk3288w before
> > >>> booting.
> > >>>
> > >>> So, this support during of board setup code of rk3288.
> > >>>
> > >>> Signed-off-by: Jagan Teki <ja...@amarulasolutions.com>
> > >>> ---
> > >>> arch/arm/mach-rockchip/Kconfig | 1 +
> > >>> arch/arm/mach-rockchip/rk3288/rk3288.c | 26
> > >>> ++++++++++++++++++++++++++
> > >>> 2 files changed, 27 insertions(+)
> > >>>
> > >>> diff --git a/arch/arm/mach-rockchip/Kconfig
> > >>> b/arch/arm/mach-rockchip/Kconfig
> > >>> index b1008a5058..822d8d4e9c 100644
> > >>> --- a/arch/arm/mach-rockchip/Kconfig
> > >>> +++ b/arch/arm/mach-rockchip/Kconfig
> > >>> @@ -98,6 +98,7 @@ config ROCKCHIP_RK322X
> > >>> config ROCKCHIP_RK3288
> > >>> bool "Support Rockchip RK3288"
> > >>> select CPU_V7A
> > >>> + select OF_BOARD_SETUP
> > >>> select SUPPORT_SPL
> > >>> select SPL
> > >>> select SUPPORT_TPL
> > >>> diff --git a/arch/arm/mach-rockchip/rk3288/rk3288.c
> > >>> b/arch/arm/mach-rockchip/rk3288/rk3288.c
> > >>> index 804abe8a1b..8a682675e6 100644
> > >>> --- a/arch/arm/mach-rockchip/rk3288/rk3288.c
> > >>> +++ b/arch/arm/mach-rockchip/rk3288/rk3288.c
> > >>> @@ -115,6 +115,32 @@ int rk_board_late_init(void)
> > >>> return rk3288_board_late_init();
> > >>> }
> > >>>
> > >>> +#ifdef CONFIG_OF_BOARD_SETUP
> > >>> +
> > >>> +#define RK3288_HDMI_PHYS 0xff980000
> > >>> +#define RK3288W_HDMI_REV 0x1A
> > >>> +#define HDMI_CONFIG0_ID 0x04
> > >>> +
> > >>> +int ft_board_setup(void *blob, bd_t *bd)
> > >>> +{
> > >>> + u8 config0;
> > >>> + int ret;
> > >>> +
> > >>> + config0 = readb(RK3288_HDMI_PHYS + HDMI_CONFIG0_ID);
> > >>> + if (config0 == RK3288W_HDMI_REV) {
> > >>> + ret = fdt_setprop_string(blob, 0,
> > >>> + "compatible",
> > >>> "rockchip,rk3288w");
> > >>
> > >> Does this end up replacing the entire top-level compatible property?
> > >> i.e. from:
> > >>
> > >> compatible = "vendor,board\0rockchip,rk3288";
> > >>
> > >> to just:
> > >>
> > >> compatible = "rockchip,rk3288w";
> > >>
> > >> If so, that's a bit of a problem for various drivers that care about the
> > >> actual board compatible rather than the SoC.
> > >
> > > Yes, It looks replacing the entire compatible. I think the root
> > > compatible is mostly untouchable because of this reason.
> > >
> > > But, if we skip the root compatible and trying to replace individual
> > > nodes for W revision then it requires extra registration code on in
> > > the Linux drivers like Linux clock driver is registering the clock
> > > with rockchip,rk3288-cru but updating this compatible with
> > > rockchip,rk3288w-cru will require another registration code. Having
> > > common rockchip,rk3288w can be possible to check any code in the tree.
> >
> > Right, it's definitely reasonable to update the top-level SoC
> > compatible, we just need to be prepared to deal with a whole string list
> > here. It looks like libfdt doesn't offer any nice helpers for
> > inserting/removing/updating in string lists, but given that the SoC
> > should be the last entry here we might be able to cheat a bit - just get
> > the whole raw property, check that the final characters are exactly
> > "rockchip,rk3288", and if so append a "w" to the end and write it back.
>
> Look like exiting fdt helper does print the compatible up to \0
> instead of whole root compatible, at least I have checked with
> fdt_getpro and fdt_get_property.
Look like we didn't have any requirement to change the root compatible
at this point since disabling ohci driver for legacy rk3288 revision
chips of no use.
Jagan.
