[PATCH 2/2] clk: hi6220: initialize UART1 clock to 150MHz

Jorge Ramirez jorge.ramirez-ortiz at linaro.org
Tue Jun 28 04:56:50 PDT 2016


On 06/28/2016 12:31 PM, Guodong Xu wrote:
> From: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz at linaro.org>
>
> Early at boot, during the sys_clk initialization, make sure UART1 uses
> the higher frequency clock.
>
> This enables support for higher baud rates (up to 3Mbps) required to
> support faster bluetooth transfers.
>
> Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz at linaro.org>
> Signed-off-by: Guodong Xu <guodong.xu at linaro.org>
> ---
>   drivers/clk/hisilicon/clk-hi6220.c | 12 ++++++++++--
>   1 file changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/clk/hisilicon/clk-hi6220.c b/drivers/clk/hisilicon/clk-hi6220.c
> index a36ffcb..55bd9bb 100644
> --- a/drivers/clk/hisilicon/clk-hi6220.c
> +++ b/drivers/clk/hisilicon/clk-hi6220.c
> @@ -11,6 +11,7 @@
>    */
>   
>   #include <linux/kernel.h>
> +#include <linux/clk.h>
>   #include <linux/clk-provider.h>
>   #include <linux/clkdev.h>
>   #include <linux/io.h>
> @@ -70,10 +71,10 @@ static struct hisi_gate_clock hi6220_separated_gate_clks_ao[] __initdata = {
>   	{ HI6220_UART0_PCLK,  "uart0_pclk",  "clk_tcxo", CLK_SET_RATE_PARENT|CLK_IGNORE_UNUSED, 0x630, 24, 0, },
>   };
>   
> +static struct hisi_clock_data *clk_data_ao;
> +
>   static void __init hi6220_clk_ao_init(struct device_node *np)
>   {
> -	struct hisi_clock_data *clk_data_ao;
> -
>   	clk_data_ao = hisi_clk_init(np, HI6220_AO_NR_CLKS);
>   	if (!clk_data_ao)
>   		return;
> @@ -192,6 +193,13 @@ static void __init hi6220_clk_sys_init(struct device_node *np)
>   
>   	hi6220_clk_register_divider(hi6220_div_clks_sys,
>   			ARRAY_SIZE(hi6220_div_clks_sys), clk_data);
> +
> +	if (!clk_data_ao)
> +		return;
> +
> +	/* enable high speed clock on UART1 mux */
> +	clk_set_parent(clk_data->clk_data.clks[HI6220_UART1_SRC],
> +			clk_data_ao->clk_data.clks[HI6220_150M]);
>   }
>   CLK_OF_DECLARE(hi6220_clk_sys, "hisilicon,hi6220-sysctrl", hi6220_clk_sys_init);
>   

please bear with me on this. it does need rework.





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