Re: [PATCH 1/2] clocksource/drivers/imx-tpm: correct some registers operation flow

From: Rob Herring
Date: Tue Mar 27 2018 - 11:06:53 EST


On Mon, Mar 26, 2018 at 03:47:40PM +0800, Anson Huang wrote:
> According to i.MX7ULP reference manual, TPM_SC_CPWMS can ONLY be
> written when counter is disabled, TPM_SC_TOF is write-1-clear,
> TPM_C0SC_CHF is also write-1-clear, correct these registers
> initialization flow;
>
> Replace incorret clock name igp with ipg.

incorrect

This looks like an unrelated change.

>
> Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
> ---
> Documentation/devicetree/bindings/timer/nxp,tpm-timer.txt | 2 +-

Though you have the same typo, this should be a separate change from the
driver.

> drivers/clocksource/timer-imx-tpm.c | 10 ++++++++--
> 2 files changed, 9 insertions(+), 3 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/timer/nxp,tpm-timer.txt b/Documentation/devicetree/bindings/timer/nxp,tpm-timer.txt
> index b4aa7dd..f82087b 100644
> --- a/Documentation/devicetree/bindings/timer/nxp,tpm-timer.txt
> +++ b/Documentation/devicetree/bindings/timer/nxp,tpm-timer.txt
> @@ -15,7 +15,7 @@ Required properties:
> - interrupts : Should be the clock event device interrupt.
> - clocks : The clocks provided by the SoC to drive the timer, must contain
> an entry for each entry in clock-names.
> -- clock-names : Must include the following entries: "igp" and "per".
> +- clock-names : Must include the following entries: "ipg" and "per".
>
> Example:
> tpm5: tpm@40260000 {
> diff --git a/drivers/clocksource/timer-imx-tpm.c b/drivers/clocksource/timer-imx-tpm.c
> index 21bffdc..7403e49 100644
> --- a/drivers/clocksource/timer-imx-tpm.c
> +++ b/drivers/clocksource/timer-imx-tpm.c
> @@ -20,6 +20,7 @@
> #define TPM_SC 0x10
> #define TPM_SC_CMOD_INC_PER_CNT (0x1 << 3)
> #define TPM_SC_CMOD_DIV_DEFAULT 0x3
> +#define TPM_SC_TOF_MASK (0x1 << 7)
> #define TPM_CNT 0x14
> #define TPM_MOD 0x18
> #define TPM_STATUS 0x1c
> @@ -29,6 +30,7 @@
> #define TPM_C0SC_MODE_SHIFT 2
> #define TPM_C0SC_MODE_MASK 0x3c
> #define TPM_C0SC_MODE_SW_COMPARE 0x4
> +#define TPM_C0SC_CHF_MASK (0x1 << 7)
> #define TPM_C0V 0x24
>
> static void __iomem *timer_base;
> @@ -179,7 +181,7 @@ static int __init tpm_timer_init(struct device_node *np)
> ipg = of_clk_get_by_name(np, "ipg");
> per = of_clk_get_by_name(np, "per");
> if (IS_ERR(ipg) || IS_ERR(per)) {
> - pr_err("tpm: failed to get igp or per clk\n");
> + pr_err("tpm: failed to get ipg or per clk\n");
> ret = -ENODEV;
> goto err_clk_get;
> }
> @@ -205,9 +207,13 @@ static int __init tpm_timer_init(struct device_node *np)
> * 4) Channel0 disabled
> * 5) DMA transfers disabled
> */
> + /* make sure counter is disabled */
> writel(0, timer_base + TPM_SC);
> + /* TOF is W1C */
> + writel(TPM_SC_TOF_MASK, timer_base + TPM_SC);
> writel(0, timer_base + TPM_CNT);
> - writel(0, timer_base + TPM_C0SC);
> + /* CHF is W1C */
> + writel(TPM_C0SC_CHF_MASK, timer_base + TPM_C0SC);
>
> /* increase per cnt, div 8 by default */
> writel(TPM_SC_CMOD_INC_PER_CNT | TPM_SC_CMOD_DIV_DEFAULT,
> --
> 2.7.4
>
> --
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