[PATCH] ARM i.MX6: Fix ethernet PLL clocks

Shawn Guo shawn.guo at linaro.org
Thu Nov 22 03:42:31 EST 2012


On Wed, Nov 21, 2012 at 02:47:32PM +0100, Sascha Hauer wrote:
> In current code the ethernet PLL (according to code pll8, according to datasheet
> pll6)

Yes, just checked the latest RM, it gets renumbered so.

> is not handled correctly. The PLL runs at 500MHz and has different outputs.
> Only the enet reference clock is implemented. This patch changes the PLL so that
> it outputs 500MHz and adds the additional outputs as dividers. This now matches
> the datasheet which says:
> 
> > This PLL synthesizes a low jitter clock from 24 MHz reference clock.
> > The PLL outputs a 500 MHz clock. The reference clocks generated by this PLL are:
> >  • Ref_PCIe = 125 MHz
> >  • Ref_SATA = 100 MHz
> >  • Ref_ethernet, which is configurable based on the PLL_ENET[1:0] register field.
> 
> Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
> ---
>  .../devicetree/bindings/clock/imx6q-clock.txt      |    5 ++
>  arch/arm/mach-imx/clk-imx6q.c                      |   18 +++++-
>  arch/arm/mach-imx/clk-pllv3.c                      |   59 +-------------------
>  3 files changed, 24 insertions(+), 58 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/clock/imx6q-clock.txt b/Documentation/devicetree/bindings/clock/imx6q-clock.txt
> index 492bd99..94311e2 100644
> --- a/Documentation/devicetree/bindings/clock/imx6q-clock.txt
> +++ b/Documentation/devicetree/bindings/clock/imx6q-clock.txt
> @@ -198,6 +198,11 @@ clocks and IDs.
>  	usbphy2			183
>  	ldb_di0_div_3_5		184
>  	ldb_di1_div_3_5		185
> +	sata_ref		186
> +	sata_ref_100m		187
> +	pcie_ref		188
> +	pcie_ref_125m		189
> +	enet_ref		190
>  
>  Examples:
>  
> diff --git a/arch/arm/mach-imx/clk-imx6q.c b/arch/arm/mach-imx/clk-imx6q.c
> index 3ec242f..95f8ea5 100644
> --- a/arch/arm/mach-imx/clk-imx6q.c
> +++ b/arch/arm/mach-imx/clk-imx6q.c
> @@ -153,7 +153,7 @@ enum mx6q_clks {
>  	usdhc4, vdo_axi, vpu_axi, cko1, pll1_sys, pll2_bus, pll3_usb_otg,
>  	pll4_audio, pll5_video, pll6_mlb, pll7_usb_host, pll8_enet, ssi1_ipg,
>  	ssi2_ipg, ssi3_ipg, rom, usbphy1, usbphy2, ldb_di0_div_3_5, ldb_di1_div_3_5,
> -	clk_max
> +	sata_ref, sata_ref_100m, pcie_ref, pcie_ref_125m, enet_ref, clk_max

The clk_max was put on a separate line on purpose, so that you can add
new ones with + lines only.

>  };
>  
>  static struct clk *clk[clk_max];
> @@ -163,6 +163,13 @@ static enum mx6q_clks const clks_init_on[] __initconst = {
>  	mmdc_ch0_axi, rom,
>  };
>  
> +static struct clk_div_table clk_enet_ref_table[] = {
> +	{ .val = 0, .div = 20, },
> +	{ .val = 1, .div = 10, },
> +	{ .val = 2, .div = 5, },
> +	{ .val = 3, .div = 4, },
> +};
> +
>  int __init mx6q_clocks_init(void)
>  {
>  	struct device_node *np;
> @@ -202,6 +209,15 @@ int __init mx6q_clocks_init(void)
>  	clk[usbphy1] = imx_clk_gate("usbphy1", "pll3_usb_otg", base + 0x10, 6);
>  	clk[usbphy2] = imx_clk_gate("usbphy2", "pll7_usb_host", base + 0x20, 6);
>  
> +	clk[sata_ref] = imx_clk_gate("sata_ref", "pll8_enet", base + 0x20, 20);
> +	clk[pcie_ref] = imx_clk_gate("pcie_ref", "pll8_enet", base + 0x20, 19);

Offset 0x20 for PLL_ENET?

> +	clk[sata_ref_100m] = imx_clk_fixed_factor("sata_ref_100m", "sata_ref", 1, 5);
> +	clk[pcie_ref_125m] = imx_clk_fixed_factor("pcie_ref_100m", "pcie_ref", 1, 4);

s/pcie_ref_100m/pcie_ref_125m

Also, don't we generally have divider/factor be parent of gate, do we?

> +
> +	clk[enet_ref] = clk_register_divider_table(NULL, "enet_ref", "pll8_enet", 0,
> +			base + 0x20, 0, 2, 0, clk_enet_ref_table,

Ditto on offset?

Shawn

> +			&imx_ccm_lock);
> +
>  	/*                                name              parent_name        reg       idx */
>  	clk[pll2_pfd0_352m] = imx_clk_pfd("pll2_pfd0_352m", "pll2_bus",     base + 0x100, 0);
>  	clk[pll2_pfd1_594m] = imx_clk_pfd("pll2_pfd1_594m", "pll2_bus",     base + 0x100, 1);
> diff --git a/arch/arm/mach-imx/clk-pllv3.c b/arch/arm/mach-imx/clk-pllv3.c
> index 36aac94..f5e210a 100644
> --- a/arch/arm/mach-imx/clk-pllv3.c
> +++ b/arch/arm/mach-imx/clk-pllv3.c
> @@ -287,66 +287,13 @@ static const struct clk_ops clk_pllv3_av_ops = {
>  static unsigned long clk_pllv3_enet_recalc_rate(struct clk_hw *hw,
>  						unsigned long parent_rate)
>  {
> -	struct clk_pllv3 *pll = to_clk_pllv3(hw);
> -	u32 div = readl_relaxed(pll->base) & pll->div_mask;
> -
> -	switch (div) {
> -	case 0:
> -		return 25000000;
> -	case 1:
> -		return 50000000;
> -	case 2:
> -		return 100000000;
> -	case 3:
> -		return 125000000;
> -	}
> -
> -	return 0;
> +	return 500000000;
>  }
>  
>  static long clk_pllv3_enet_round_rate(struct clk_hw *hw, unsigned long rate,
>  				      unsigned long *prate)
>  {
> -	if (rate >= 125000000)
> -		rate = 125000000;
> -	else if (rate >= 100000000)
> -		rate = 100000000;
> -	else if (rate >= 50000000)
> -		rate = 50000000;
> -	else
> -		rate = 25000000;
> -	return rate;
> -}
> -
> -static int clk_pllv3_enet_set_rate(struct clk_hw *hw, unsigned long rate,
> -		unsigned long parent_rate)
> -{
> -	struct clk_pllv3 *pll = to_clk_pllv3(hw);
> -	u32 val, div;
> -
> -	switch (rate) {
> -	case 25000000:
> -		div = 0;
> -		break;
> -	case 50000000:
> -		div = 1;
> -		break;
> -	case 100000000:
> -		div = 2;
> -		break;
> -	case 125000000:
> -		div = 3;
> -		break;
> -	default:
> -		return -EINVAL;
> -	}
> -
> -	val = readl_relaxed(pll->base);
> -	val &= ~pll->div_mask;
> -	val |= div;
> -	writel_relaxed(val, pll->base);
> -
> -	return 0;
> +	return 500000000;
>  }
>  
>  static const struct clk_ops clk_pllv3_enet_ops = {
> @@ -355,8 +302,6 @@ static const struct clk_ops clk_pllv3_enet_ops = {
>  	.enable		= clk_pllv3_enable,
>  	.disable	= clk_pllv3_disable,
>  	.recalc_rate	= clk_pllv3_enet_recalc_rate,
> -	.round_rate	= clk_pllv3_enet_round_rate,
> -	.set_rate	= clk_pllv3_enet_set_rate,
>  };
>  
>  static const struct clk_ops clk_pllv3_mlb_ops = {
> -- 
> 1.7.10.4
> 




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