ARM: imx: AHB rate must be set to 132MHz on i.mx6sl

Submitted by Anson Huang on Jan. 7, 2014, 5:46 p.m.

Details

Message ID 1389116764-27951-1-git-send-email-b20788@freescale.com
State New
Headers show

Commit Message

Anson Huang Jan. 7, 2014, 5:46 p.m.
The reset value of AHB divider is 3, so current AHB rate
is 99MHz which is not correct for kernel, need to ensure
AHB rate is 132MHz in clk driver, as ipg is sourcing from
AHB, and it should be 66MHz by default.

Signed-off-by: Anson Huang <b20788@freescale.com>
---
 arch/arm/mach-imx/clk-imx6sl.c |    8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

Comments

Shawn Guo Jan. 8, 2014, 12:37 p.m.
On Tue, Jan 07, 2014 at 12:46:04PM -0500, Anson Huang wrote:
> The reset value of AHB divider is 3, so current AHB rate
> is 99MHz which is not correct for kernel, need to ensure
> AHB rate is 132MHz in clk driver, as ipg is sourcing from
> AHB, and it should be 66MHz by default.
> 
> Signed-off-by: Anson Huang <b20788@freescale.com>
> ---
>  arch/arm/mach-imx/clk-imx6sl.c |    8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/arm/mach-imx/clk-imx6sl.c b/arch/arm/mach-imx/clk-imx6sl.c
> index a747a7d..e6900e9 100644
> --- a/arch/arm/mach-imx/clk-imx6sl.c
> +++ b/arch/arm/mach-imx/clk-imx6sl.c
> @@ -1,5 +1,5 @@
>  /*
> - * Copyright 2013 Freescale Semiconductor, Inc.
> + * Copyright 2013-2014 Freescale Semiconductor, Inc.
>   *
>   * This program is free software; you can redistribute it and/or modify
>   * it under the terms of the GNU General Public License version 2 as
> @@ -72,6 +72,7 @@ static void __init imx6sl_clocks_init(struct device_node *ccm_node)
>  	void __iomem *base;
>  	int irq;
>  	int i;
> +	int ret;
>  
>  	clks[IMX6SL_CLK_DUMMY] = imx_clk_fixed("dummy", 0);
>  	clks[IMX6SL_CLK_CKIL] = imx_obtain_fixed_clock("ckil", 0);
> @@ -256,6 +257,11 @@ static void __init imx6sl_clocks_init(struct device_node *ccm_node)
>  	clk_register_clkdev(clks[IMX6SL_CLK_GPT], "ipg", "imx-gpt.0");
>  	clk_register_clkdev(clks[IMX6SL_CLK_GPT_SERIAL], "per", "imx-gpt.0");
>  
> +	/* Ensure the AHB clk is at 132MHz. */
> +	ret = clk_set_rate(clks[IMX6SL_CLK_AHB], 132000000);
> +	if (ret)
> +		pr_warn("%s: failed to set AHB clock rate %d!\n", __func__, ret);

I changed it as below to avoid one 'line over 80 characters' warning,
and applied the patch.

		pr_warn("%s: failed to set AHB clock rate %d!\n",
			__func__, ret);

Shawn

> +
>  	if (IS_ENABLED(CONFIG_USB_MXS_PHY)) {
>  		clk_prepare_enable(clks[IMX6SL_CLK_USBPHY1_GATE]);
>  		clk_prepare_enable(clks[IMX6SL_CLK_USBPHY2_GATE]);
> -- 
> 1.7.9.5
> 
>

Patch hide | download patch | download mbox

diff --git a/arch/arm/mach-imx/clk-imx6sl.c b/arch/arm/mach-imx/clk-imx6sl.c
index a747a7d..e6900e9 100644
--- a/arch/arm/mach-imx/clk-imx6sl.c
+++ b/arch/arm/mach-imx/clk-imx6sl.c
@@ -1,5 +1,5 @@ 
 /*
- * Copyright 2013 Freescale Semiconductor, Inc.
+ * Copyright 2013-2014 Freescale Semiconductor, Inc.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -72,6 +72,7 @@  static void __init imx6sl_clocks_init(struct device_node *ccm_node)
 	void __iomem *base;
 	int irq;
 	int i;
+	int ret;
 
 	clks[IMX6SL_CLK_DUMMY] = imx_clk_fixed("dummy", 0);
 	clks[IMX6SL_CLK_CKIL] = imx_obtain_fixed_clock("ckil", 0);
@@ -256,6 +257,11 @@  static void __init imx6sl_clocks_init(struct device_node *ccm_node)
 	clk_register_clkdev(clks[IMX6SL_CLK_GPT], "ipg", "imx-gpt.0");
 	clk_register_clkdev(clks[IMX6SL_CLK_GPT_SERIAL], "per", "imx-gpt.0");
 
+	/* Ensure the AHB clk is at 132MHz. */
+	ret = clk_set_rate(clks[IMX6SL_CLK_AHB], 132000000);
+	if (ret)
+		pr_warn("%s: failed to set AHB clock rate %d!\n", __func__, ret);
+
 	if (IS_ENABLED(CONFIG_USB_MXS_PHY)) {
 		clk_prepare_enable(clks[IMX6SL_CLK_USBPHY1_GATE]);
 		clk_prepare_enable(clks[IMX6SL_CLK_USBPHY2_GATE]);