[PATCH 1/3] ARM: uniphier: move NAND reset assertion to U-Boot proper from SPL

[Masahiro Yamada]

On Fri, Feb 14, 2020 at 8:55 PM Masahiro Yamada
<yamada.masahiro at socionext.com> wrote:
>
> The comment /* deassert reset */ is wrong. It asserts the reset.
>
> It no longer needs to stay in SPL. The NAND controller reset is
> handled  in the driver. So, this assert can be moved to the
> board_init() of U-Boot proper.
>
> Signed-off-by: Masahiro Yamada <yamada.masahiro at socionext.com>
> ---
>
>  arch/arm/mach-uniphier/Makefile            |  1 +
>  arch/arm/mach-uniphier/board_init.c        |  4 ++
>  arch/arm/mach-uniphier/clk/clk-early-ld4.c |  7 ----
>  arch/arm/mach-uniphier/init.h              |  8 ++++
>  arch/arm/mach-uniphier/nand-reset.c        | 43 ++++++++++++++++++++++
>  5 files changed, 56 insertions(+), 7 deletions(-)
>  create mode 100644 arch/arm/mach-uniphier/nand-reset.c
>
> diff --git a/arch/arm/mach-uniphier/Makefile b/arch/arm/mach-uniphier/Makefile
> index 115af244cd55..769778cf5083 100644
> --- a/arch/arm/mach-uniphier/Makefile
> +++ b/arch/arm/mach-uniphier/Makefile
> @@ -22,6 +22,7 @@ endif
>  obj-$(CONFIG_MICRO_SUPPORT_CARD) += micro-support-card.o
>  obj-y += pinctrl-glue.o
>  obj-$(CONFIG_MMC) += mmc-first-dev.o
> +obj-$(CONFIG_NAND_DENALI) += nand-reset.o
>  obj-y += fdt-fixup.o
>
>  endif
> diff --git a/arch/arm/mach-uniphier/board_init.c b/arch/arm/mach-uniphier/board_init.c
> index 99727a300420..4f9cd6e722c1 100644
> --- a/arch/arm/mach-uniphier/board_init.c
> +++ b/arch/arm/mach-uniphier/board_init.c
> @@ -141,6 +141,10 @@ int board_init(void)
>
>         support_card_late_init();
>
> +       led_puts("U4");
> +
> +       uniphier_nand_reset_assert();
> +
>         led_puts("Uboo");
>
>         return 0;
> diff --git a/arch/arm/mach-uniphier/clk/clk-early-ld4.c b/arch/arm/mach-uniphier/clk/clk-early-ld4.c
> index f32f78dd26d8..0f9ce6509768 100644
> --- a/arch/arm/mach-uniphier/clk/clk-early-ld4.c
> +++ b/arch/arm/mach-uniphier/clk/clk-early-ld4.c
> @@ -15,13 +15,6 @@ void uniphier_ld4_early_clk_init(void)
>  {
>         u32 tmp;
>
> -       /* deassert reset */
> -       if (spl_boot_device() != BOOT_DEVICE_NAND) {
> -               tmp = readl(sc_base + SC_RSTCTRL);
> -               tmp &= ~SC_RSTCTRL_NRST_NAND;
> -               writel(tmp, sc_base + SC_RSTCTRL);
> -       };
> -
>         /* provide clocks */
>         tmp = readl(sc_base + SC_CLKCTRL);
>         tmp |= SC_CLKCTRL_CEN_SBC | SC_CLKCTRL_CEN_PERI;
> diff --git a/arch/arm/mach-uniphier/init.h b/arch/arm/mach-uniphier/init.h
> index 9dc5b885a5fe..3c77f4885348 100644
> --- a/arch/arm/mach-uniphier/init.h
> +++ b/arch/arm/mach-uniphier/init.h
> @@ -101,6 +101,14 @@ unsigned int uniphier_boot_device_raw(void);
>  int uniphier_have_internal_stm(void);
>  int uniphier_boot_from_backend(void);
>  int uniphier_pin_init(const char *pinconfig_name);
> +
> +#ifdef CONFIG_NAND_DENALI
> +void uniphier_nand_reset_assert(void);
> +#else
> +static inline void uniphier_nand_reset_assert(void)
> +{
> +}
> +#endif
>  #ifdef CONFIG_ARM64
>  void uniphier_mem_map_init(unsigned long dram_base, unsigned long dram_size);
>  #else
> diff --git a/arch/arm/mach-uniphier/nand-reset.c b/arch/arm/mach-uniphier/nand-reset.c
> new file mode 100644
> index 000000000000..b8f75a5f189f
> --- /dev/null
> +++ b/arch/arm/mach-uniphier/nand-reset.c
> @@ -0,0 +1,43 @@
> +// SPDX-License-Identifier: GPL-2.0 or later
> +/*
> + * Copyright (C) 2020 Socionext Inc.
> + *   Author: Masahiro Yamada <yamada.masahiro at socionext.com>
> + */
> +
> +#include <linux/errno.h>
> +#include <dm.h>
> +#include <dm/uclass-internal.h>
> +#include <reset.h>
> +
> +#include "init.h"
> +
> +/*
> + * Assert the Denali NAND controller reset if found.
> + *
> + * On LD4, the bootstrap process starts running after power-on reset regardless
> + * of the boot mode, here the pin-mux is not necessarily set up for NAND, then
> + * the controller is stuck. Assert the controller reset here, and should be
> + * deasserted in the driver after the pin-mux is correctly handled. For other
> + * SoCs, the bootstrap runs only when the boot mode selects ONFi, but it is yet
> + * effective when the boot swap is on. So, the reset should be asserted anyway.
> + */
> +void uniphier_nand_reset_assert(void)
> +{
> +       struct udevice *dev;
> +       struct reset_ctl_bulk resets;
> +       int ret;
> +
> +       ret = uclass_find_first_device(UCLASS_MTD, &dev);
> +       if (ret)
> +               return;

I changed this hunk as follows, and applied to u-boot-uniphier.


index b8f75a5f18..11cadaabd8 100644
--- a/arch/arm/mach-uniphier/nand-reset.c
+++ b/arch/arm/mach-uniphier/nand-reset.c
@@ -28,7 +28,7 @@ void uniphier_nand_reset_assert(void)
        int ret;

        ret = uclass_find_first_device(UCLASS_MTD, &dev);
-       if (ret)
+       if (ret || !dev)
                return;

        /* make sure this is the Denali NAND controller */







> +       /* make sure this is the Denali NAND controller */
> +       if (strcmp(dev->driver->name, "denali-nand-dt"))
> +               return;
> +
> +       ret = reset_get_bulk(dev, &resets);
> +       if (ret)
> +               return;
> +
> +       reset_assert_bulk(&resets);
> +}
> --
> 2.17.1
>


-- 
Best Regards
Masahiro Yamada