[PATCH v7 15/20] tegra: fdt: Add function to return peripheral/clock ID

[Tom Warren]

Simon,

> -----Original Message-----
> From: Simon Glass [mailto:sjg at chromium.org]
> Sent: Tuesday, February 28, 2012 11:08 AM
> To: U-Boot Mailing List
> Cc: Tom Warren; Stephen Warren; Simon Glass; linux-tegra at vger.kernel.org;
> Jerry Van Baren; Devicetree Discuss
> Subject: [PATCH v7 15/20] tegra: fdt: Add function to return
> peripheral/clock ID
> 
> A common requirement is to find the clock ID for a peripheral. This is the
> second cell of the 'clocks' property (the first being the phandle itself).
> 
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
> Changes in v4:
> - Add fdtdec function to return peripheral ID
> 
> Changes in v6:
> - Move peripheral decode function into Tegra's clock.c
> 
> Changes in v7:
> - Add belts and braces checking of device tree clock ID
> 
>  arch/arm/cpu/armv7/tegra2/clock.c        |   56
> ++++++++++++++++++++++++++++++
>  arch/arm/include/asm/arch-tegra2/clock.h |   13 +++++++
>  2 files changed, 69 insertions(+), 0 deletions(-)
> 
> diff --git a/arch/arm/cpu/armv7/tegra2/clock.c
> b/arch/arm/cpu/armv7/tegra2/clock.c
> index 11d2346..959322b 100644
> --- a/arch/arm/cpu/armv7/tegra2/clock.c
> +++ b/arch/arm/cpu/armv7/tegra2/clock.c
> @@ -28,6 +28,7 @@
>  #include <asm/arch/tegra2.h>
>  #include <common.h>
>  #include <div64.h>
> +#include <fdtdec.h>
> 
>  /*
>   * This is our record of the current clock rate of each clock. We don't @@
> -918,6 +919,61 @@ void clock_ll_start_uart(enum periph_id periph_id)
>  	reset_set_enable(periph_id, 0);
>  }
> 
> +/*
> + * Convert a device tree clock ID to our peripheral ID. They are mostly
> + * the same but we are very cautious so we check that a valid clock ID
> +is
> + * provided.
> + *
> + * @param clk_id	Clock ID according to tegra2 device tree binding
> + * @return peripheral ID, or PERIPH_ID_NONE if the clock ID is invalid
> +*/ static enum periph_id clk_id_to_periph_id(int clk_id) {
> +	if (clk_id > 95)
> +		return PERIPH_ID_NONE;
> +
> +	switch (clk_id) {
> +	case 1:
> +	case 2:
> +	case 7:
> +	case 10:
> +	case 20:
> +	case 30:
> +	case 35:
> +	case 49:
> +	case 56:
> +	case 74:
> +	case 76:
> +	case 77:
> +	case 78:
> +	case 79:
> +	case 80:
> +	case 81:
> +	case 82:
> +	case 83:
> +	case 91:
> +	case 95:
> +		return PERIPH_ID_NONE;
> +	default:
> +		return clk_id;
> +	}
> +}
> +
> +int clock_decode_periph_id(const void *blob, int node) {
> +	enum periph_id id;
> +	u32 cell[2];
> +	int err;
> +
> +	err = fdtdec_get_int_array(blob, node, "clocks", cell,
> +				   ARRAY_SIZE(cell));

This call to fdtdec_get_int_array() breaks Harmony and Ventana builds, since they're not yet DT-enabled (CONFIG_OF_CONTROL isn't #defined).

I'd fix this myself, but I'm not sure what the correct fix is to keep Harmony/Ventana building & booting.

Please fix, test on all Tegra2 builds (MAKEALL -s tegra2) and resend. Thanks.

Tom

> +	if (err)
> +		return -1;
> +	id = clk_id_to_periph_id(cell[1]);
> +	assert(clock_periph_id_isvalid(id));
> +	return id;
> +}
> +
>  int clock_verify(void)
>  {
>  	struct clk_pll *pll = get_pll(CLOCK_ID_PERIPH); diff --git
> a/arch/arm/include/asm/arch-tegra2/clock.h b/arch/arm/include/asm/arch-
> tegra2/clock.h
> index 080ef18..6b12c76 100644
> --- a/arch/arm/include/asm/arch-tegra2/clock.h
> +++ b/arch/arm/include/asm/arch-tegra2/clock.h
> @@ -177,6 +177,7 @@ enum periph_id {
>  	PERIPH_ID_CRAM2,
> 
>  	PERIPH_ID_COUNT,
> +	PERIPH_ID_NONE = -1,
>  };
> 
>  /* Converts a clock number to a clock register: 0=L, 1=H, 2=U */ @@ -355,6
> +356,18 @@ unsigned clock_get_rate(enum clock_id clkid);
>   */
>  void clock_ll_start_uart(enum periph_id periph_id);
> 
> +/**
> + * Decode a peripheral ID from a device tree node.
> + *
> + * This works by looking up the peripheral's 'clocks' node and reading
> +out
> + * the second cell, which is the clock number / peripheral ID.
> + *
> + * @param blob		FDT blob to use
> + * @param node		Node to look at
> + * @return peripheral ID, or PERIPH_ID_NONE if none  */ enum periph_id
> +clock_decode_periph_id(const void *blob, int node);
> +
>  /*
>   * Checks that clocks are valid and prints a warning if not
>   *
> --
> 1.7.7.3
-- 
nvpublic