On 17.01.18 20:46, Simon Glass wrote: > Hi Alex, > > On 17 January 2018 at 00:54, Alexander Graf <ag...@suse.de> wrote: >> Now that we have all infrastructure in place to dynamically determine whether >> a serial device is actually usable (read: routed to user accessible pins), we >> can wire it up to the board. >> >> This patch adds support to determine whether the pl011 or mini-uart or no >> serial >> is routed to the UART RX/TX pins on the Raspberry Pi family of boards. >> >> Signed-off-by: Alexander Graf <ag...@suse.de> >> --- >> board/raspberrypi/rpi/rpi.c | 69 >> +++++++++++++++++++++++++++++++++++++++++++++ >> 1 file changed, 69 insertions(+) >> >> diff --git a/board/raspberrypi/rpi/rpi.c b/board/raspberrypi/rpi/rpi.c >> index a96d5d8952..b0cdad70f7 100644 >> --- a/board/raspberrypi/rpi/rpi.c >> +++ b/board/raspberrypi/rpi/rpi.c >> @@ -24,9 +24,16 @@ >> #include <asm/armv8/mmu.h> >> #endif >> #include <watchdog.h> >> +#include <asm/io.h> >> >> DECLARE_GLOBAL_DATA_PTR; >> >> +/* >> + * This is the GPIO pin that the user facing UART RX line is attached to. >> + * We use this pin to determine which serial device is available. >> + */ >> +#define BCM2835_GPIO_RX 15 >> + >> /* From lowlevel_init.S */ >> extern unsigned long fw_dtb_pointer; >> >> @@ -419,6 +426,68 @@ static void get_board_rev(void) >> printf("RPI %s (0x%x)\n", model->name, revision); >> } >> >> +/* >> + * We may get called before the device model is initialized, so we can not >> + * rely on the GPIO driver. >> + */ >> +int get_func_id(unsigned gpio) >> +{ >> + u32 val; >> + u32 node; >> + u32 *gpfsel; >> + fdt_addr_t addr; >> + fdt_size_t size; >> + >> + node = fdt_node_offset_by_compatible(gd->fdt_blob, -1, >> "brcm,bcm2835-gpio"); >> + if (node < 0) >> + return -EINVAL; >> + >> + addr = fdtdec_get_addr_size_auto_noparent(gd->fdt_blob, node, "reg", >> + 0, &size, true); >> + gpfsel = (void*)addr; >> + >> + val = readl(&gpfsel[BCM2835_GPIO_FSEL_BANK(gpio)]); >> + >> + return (val >> BCM2835_GPIO_FSEL_SHIFT(gpio) & >> BCM2835_GPIO_FSEL_MASK); >> +} > > Ick, this should be done in the GPIO driver and use gpio_get_function().
Yes, but what if users specify the serial device to be pre-reloc and don't do that for the GPIO (or really pinctrl) one? Then we'd not have the driver around to determine whether serial is active, right? Alex _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot