From 755350bcfb4ac8cbbb62bd7ee6be8271d4b2a88a Mon Sep 17 00:00:00 2001 From: Martin Blumenstingl Date: Sun, 25 Feb 2024 16:13:36 +0100 Subject: [PATCH] clocksource/drivers/arm_global_timer: Simplify prescaler register access Use GENMASK() to define the prescaler mask and make the whole driver use the mask (together with helpers such as FIELD_{GET,PREP,FIT}) instead of needing an additional shift and max value constant. Signed-off-by: Martin Blumenstingl Signed-off-by: Daniel Lezcano Link: https://lore.kernel.org/r/20240225151336.2728533-4-martin.blumenstingl@googlemail.com --- drivers/clocksource/arm_global_timer.c | 19 ++++++++----------- 1 file changed, 8 insertions(+), 11 deletions(-) diff --git a/drivers/clocksource/arm_global_timer.c b/drivers/clocksource/arm_global_timer.c index 4726a15b0afc1..ab1c8c2b66b88 100644 --- a/drivers/clocksource/arm_global_timer.c +++ b/drivers/clocksource/arm_global_timer.c @@ -9,6 +9,7 @@ #include #include +#include #include #include #include @@ -31,10 +32,7 @@ #define GT_CONTROL_COMP_ENABLE BIT(1) /* banked */ #define GT_CONTROL_IRQ_ENABLE BIT(2) /* banked */ #define GT_CONTROL_AUTO_INC BIT(3) /* banked */ -#define GT_CONTROL_PRESCALER_SHIFT 8 -#define GT_CONTROL_PRESCALER_MAX 0xFF -#define GT_CONTROL_PRESCALER_MASK (GT_CONTROL_PRESCALER_MAX << \ - GT_CONTROL_PRESCALER_SHIFT) +#define GT_CONTROL_PRESCALER_MASK GENMASK(15, 8) #define GT_INT_STATUS 0x0c #define GT_INT_STATUS_EVENT_FLAG BIT(0) @@ -248,7 +246,7 @@ static void gt_write_presc(u32 psv) reg = readl(gt_base + GT_CONTROL); reg &= ~GT_CONTROL_PRESCALER_MASK; - reg |= psv << GT_CONTROL_PRESCALER_SHIFT; + reg |= FIELD_PREP(GT_CONTROL_PRESCALER_MASK, psv); writel(reg, gt_base + GT_CONTROL); } @@ -257,8 +255,7 @@ static u32 gt_read_presc(void) u32 reg; reg = readl(gt_base + GT_CONTROL); - reg &= GT_CONTROL_PRESCALER_MASK; - return reg >> GT_CONTROL_PRESCALER_SHIFT; + return FIELD_GET(GT_CONTROL_PRESCALER_MASK, reg); } static void __init gt_delay_timer_init(void) @@ -273,9 +270,9 @@ static int __init gt_clocksource_init(void) writel(0, gt_base + GT_COUNTER0); writel(0, gt_base + GT_COUNTER1); /* set prescaler and enable timer on all the cores */ - writel(((CONFIG_ARM_GT_INITIAL_PRESCALER_VAL - 1) << - GT_CONTROL_PRESCALER_SHIFT) - | GT_CONTROL_TIMER_ENABLE, gt_base + GT_CONTROL); + writel(FIELD_PREP(GT_CONTROL_PRESCALER_MASK, + CONFIG_ARM_GT_INITIAL_PRESCALER_VAL - 1) | + GT_CONTROL_TIMER_ENABLE, gt_base + GT_CONTROL); #ifdef CONFIG_CLKSRC_ARM_GLOBAL_TIMER_SCHED_CLOCK sched_clock_register(gt_sched_clock_read, 64, gt_target_rate); @@ -301,7 +298,7 @@ static int gt_clk_rate_change_cb(struct notifier_block *nb, psv--; /* prescaler within legal range? */ - if (psv > GT_CONTROL_PRESCALER_MAX) + if (!FIELD_FIT(GT_CONTROL_PRESCALER_MASK, psv)) return NOTIFY_BAD; /* -- 2.30.2