[U-Boot] [PATCH 3/6] rockchip: evb-rk3328: set uart2 and sdmmc io routing

[Heiko Stuebner <heiko@sntech.de>]

Hi Kever,

Am Mittwoch, 24. Mai 2017, 10:35:04 CEST schrieb Kever Yang:
> On 05/20/2017 10:29 AM, Simon Glass wrote:
> > On 16 May 2017 at 21:44, Kever Yang <kever.yang@rock-chips.com> wrote:
> >> In rk3328, some function pin may have more than one choice, and muxed
> >> with more than one IO, for example, the UART2 controller IO,
> >> TX and RX, have 3 choice(setting in com_iomux):
> >> - M0 which mux with GPIO1A0/GPIO1A1
> >> - M1 which mux with GPIO2A0/GPIO2A1
> >> - usb2phy which mux with USB2.0 DP/DM pin.
> >>
> >> We should set these IO routing in board file.
> >>
> >> Signed-off-by: Kever Yang <kever.yang@rock-chips.com>
> >> ---
> >>
> >>   board/rockchip/evb_rk3328/evb-rk3328.c | 12 ++++++++++++
> >>   1 file changed, 12 insertions(+)
> >>
> >> diff --git a/board/rockchip/evb_rk3328/evb-rk3328.c b/board/rockchip/evb_rk3328/evb-rk3328.c
> >> index a7895cb..d9dc782 100644
> >> --- a/board/rockchip/evb_rk3328/evb-rk3328.c
> >> +++ b/board/rockchip/evb_rk3328/evb-rk3328.c
> >> @@ -5,7 +5,10 @@
> >>    */
> >>
> >>   #include <common.h>
> >> +#include <asm/arch/hardware.h>
> >> +#include <asm/arch/grf_rk3328.h>
> >>   #include <asm/armv8/mmu.h>
> >> +#include <asm/io.h>
> >>   #include <dwc3-uboot.h>
> >>   #include <usb.h>
> >>
> >> @@ -13,6 +16,15 @@ DECLARE_GLOBAL_DATA_PTR;
> >>
> >>   int board_init(void)
> >>   {
> >> +#define GRF_BASE       0xff100000
> >> +       struct rk3328_grf_regs * const grf = (void *)GRF_BASE;
> >> +
> >> +       /* uart2 select m1, sdcard select m1*/
> >> +       rk_clrsetreg(&grf->com_iomux,
> >> +                    IOMUX_SEL_UART2_MASK | IOMUX_SEL_SDMMC_MASK,
> >> +                    IOMUX_SEL_UART2_M1 << IOMUX_SEL_UART2_SHIFT |
> >> +                    IOMUX_SEL_SDMMC_M1 << IOMUX_SEL_SDMMC_SHIFT);
> >> +
> >>          return 0;
> >>   }
> > This needs to be done via a call to some sort of driver. The above
> > hack is OK in SPL but not in U-Boot proper.
> 
> Yes, SPL also needs this. I thinks here should be the right place
> before there is a SPL for rk3328.
> >
> > See my comments elsewhere about using a misc driver with an IOCTL
> > interface to do this sort of thing. Although here I wonder why you
> > cannot use pinctrl?
> 
> This is different from traditional pinctrl, kernel also still not have
> final solution on this, see [0], and some people think it should be
> done in boot loader.

Just to point out that thanks to David Wu we now have a solution [1]
on the kernel side I'm pretty happy with - as part of the pinctrl driver.


Heiko


> [0] 
> http://lists.infradead.org/pipermail/linux-rockchip/2016-August/011209.html

[1] https://www.spinics.net/lists/kernel/msg2517794.html