From 65783949c813d0cad88b6a30f47737e8dfc00c86 Mon Sep 17 00:00:00 2001 From: Anson Huang Date: Wed, 28 Mar 2018 11:22:37 +0800 Subject: [PATCH] clocksource/drivers/imx-tpm: Correct some registers operation flow [ Upstream commit 506a7be93ff773d5d4cf75a59f342865605b4910 ] 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; Signed-off-by: Anson Huang Signed-off-by: Daniel Lezcano Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/clocksource/timer-imx-tpm.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/clocksource/timer-imx-tpm.c b/drivers/clocksource/timer-imx-tpm.c index 557ed25b42e3..d175b9545581 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; @@ -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,