[tip: timers/core] clocksource/drivers/timer-ti-dm: Simplify register reads with dmtimer_read()

From: tip-bot2 for Tony Lindgren
Date: Tue Oct 04 2022 - 05:29:46 EST


The following commit has been merged into the timers/core branch of tip:

Commit-ID: 90c9aada19606ae78259cef78a46646a97ec8f67
Gitweb: https://git.kernel.org/tip/90c9aada19606ae78259cef78a46646a97ec8f67
Author: Tony Lindgren <tony@xxxxxxxxxxx>
AuthorDate: Mon, 15 Aug 2022 16:12:43 +03:00
Committer: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
CommitterDate: Tue, 20 Sep 2022 10:49:45 +02:00

clocksource/drivers/timer-ti-dm: Simplify register reads with dmtimer_read()

We can simplify register read access by checking for the register write
posted mode in the read function. This way we can combine the functions
for __omap_dm_timer_read() and omap_dm_timer_read_reg() into a single
function dmtimer_read().

We update the shared register access first, the timer revision specific
register access will be updated in a later patch.

Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx>
Reviewed-by: Janusz Krzysztofik <jmkrzyszt@xxxxxxxxx>
Link: https://lore.kernel.org/r/20220815131250.34603-3-tony@xxxxxxxxxxx
Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
---
drivers/clocksource/timer-ti-dm.c | 88 +++++++++++++-----------------
1 file changed, 40 insertions(+), 48 deletions(-)

diff --git a/drivers/clocksource/timer-ti-dm.c b/drivers/clocksource/timer-ti-dm.c
index b8f8c11..070d47d 100644
--- a/drivers/clocksource/timer-ti-dm.c
+++ b/drivers/clocksource/timer-ti-dm.c
@@ -44,14 +44,28 @@ enum {
REQUEST_BY_NODE,
};

-static inline u32 __omap_dm_timer_read(struct omap_dm_timer *timer, u32 reg,
- int posted)
+/**
+ * dmtimer_read - read timer registers in posted and non-posted mode
+ * @timer: timer pointer over which read operation to perform
+ * @reg: lowest byte holds the register offset
+ *
+ * The posted mode bit is encoded in reg. Note that in posted mode, write
+ * pending bit must be checked. Otherwise a read of a non completed write
+ * will produce an error.
+ */
+static inline u32 dmtimer_read(struct omap_dm_timer *timer, u32 reg)
{
- if (posted)
- while (readl_relaxed(timer->pend) & (reg >> WPSHIFT))
+ u16 wp, offset;
+
+ wp = reg >> WPSHIFT;
+ offset = reg & 0xff;
+
+ /* Wait for a possible write pending bit in posted mode */
+ if (wp && timer->posted)
+ while (readl_relaxed(timer->pend) & wp)
cpu_relax();

- return readl_relaxed(timer->func_base + (reg & 0xff));
+ return readl_relaxed(timer->func_base + offset);
}

static inline void __omap_dm_timer_write(struct omap_dm_timer *timer,
@@ -121,13 +135,13 @@ static inline void __omap_dm_timer_stop(struct omap_dm_timer *timer,
{
u32 l;

- l = __omap_dm_timer_read(timer, OMAP_TIMER_CTRL_REG, posted);
+ l = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
if (l & OMAP_TIMER_CTRL_ST) {
l &= ~0x1;
__omap_dm_timer_write(timer, OMAP_TIMER_CTRL_REG, l, posted);
#ifdef CONFIG_ARCH_OMAP2PLUS
/* Readback to make sure write has completed */
- __omap_dm_timer_read(timer, OMAP_TIMER_CTRL_REG, posted);
+ dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
/*
* Wait for functional clock period x 3.5 to make sure that
* timer is stopped
@@ -148,9 +162,9 @@ static inline void __omap_dm_timer_int_enable(struct omap_dm_timer *timer,
}

static inline unsigned int
-__omap_dm_timer_read_counter(struct omap_dm_timer *timer, int posted)
+__omap_dm_timer_read_counter(struct omap_dm_timer *timer)
{
- return __omap_dm_timer_read(timer, OMAP_TIMER_COUNTER_REG, posted);
+ return dmtimer_read(timer, OMAP_TIMER_COUNTER_REG);
}

static inline void __omap_dm_timer_write_status(struct omap_dm_timer *timer,
@@ -160,21 +174,6 @@ static inline void __omap_dm_timer_write_status(struct omap_dm_timer *timer,
}

/**
- * omap_dm_timer_read_reg - read timer registers in posted and non-posted mode
- * @timer: timer pointer over which read operation to perform
- * @reg: lowest byte holds the register offset
- *
- * The posted mode bit is encoded in reg. Note that in posted mode write
- * pending bit must be checked. Otherwise a read of a non completed write
- * will produce an error.
- */
-static inline u32 omap_dm_timer_read_reg(struct omap_dm_timer *timer, u32 reg)
-{
- WARN_ON((reg & 0xff) < _OMAP_TIMER_WAKEUP_EN_OFFSET);
- return __omap_dm_timer_read(timer, reg, timer->posted);
-}
-
-/**
* omap_dm_timer_write_reg - write timer registers in posted and non-posted mode
* @timer: timer pointer over which write operation is to perform
* @reg: lowest byte holds the register offset
@@ -213,20 +212,14 @@ static void omap_timer_restore_context(struct omap_dm_timer *timer)

static void omap_timer_save_context(struct omap_dm_timer *timer)
{
- timer->context.ocp_cfg =
- __omap_dm_timer_read(timer, OMAP_TIMER_OCP_CFG_OFFSET, 0);
-
- timer->context.tclr =
- omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
- timer->context.twer =
- omap_dm_timer_read_reg(timer, OMAP_TIMER_WAKEUP_EN_REG);
- timer->context.tldr =
- omap_dm_timer_read_reg(timer, OMAP_TIMER_LOAD_REG);
- timer->context.tmar =
- omap_dm_timer_read_reg(timer, OMAP_TIMER_MATCH_REG);
+ timer->context.ocp_cfg = dmtimer_read(timer, OMAP_TIMER_OCP_CFG_OFFSET);
+
+ timer->context.tclr = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
+ timer->context.twer = dmtimer_read(timer, OMAP_TIMER_WAKEUP_EN_REG);
+ timer->context.tldr = dmtimer_read(timer, OMAP_TIMER_LOAD_REG);
+ timer->context.tmar = dmtimer_read(timer, OMAP_TIMER_MATCH_REG);
timer->context.tier = readl_relaxed(timer->irq_ena);
- timer->context.tsicr =
- omap_dm_timer_read_reg(timer, OMAP_TIMER_IF_CTRL_REG);
+ timer->context.tsicr = dmtimer_read(timer, OMAP_TIMER_IF_CTRL_REG);
}

static int omap_timer_context_notifier(struct notifier_block *nb,
@@ -266,8 +259,7 @@ static int omap_dm_timer_reset(struct omap_dm_timer *timer)
omap_dm_timer_write_reg(timer, OMAP_TIMER_IF_CTRL_REG, 0x06);

do {
- l = __omap_dm_timer_read(timer,
- OMAP_TIMER_V1_SYS_STAT_OFFSET, 0);
+ l = dmtimer_read(timer, OMAP_TIMER_V1_SYS_STAT_OFFSET);
} while (!l && timeout--);

if (!timeout) {
@@ -276,7 +268,7 @@ static int omap_dm_timer_reset(struct omap_dm_timer *timer)
}

/* Configure timer for smart-idle mode */
- l = __omap_dm_timer_read(timer, OMAP_TIMER_OCP_CFG_OFFSET, 0);
+ l = dmtimer_read(timer, OMAP_TIMER_OCP_CFG_OFFSET);
l |= 0x2 << 0x3;
__omap_dm_timer_write(timer, OMAP_TIMER_OCP_CFG_OFFSET, l, 0);

@@ -550,7 +542,7 @@ __u32 omap_dm_timer_modify_idlect_mask(__u32 inputmask)
list_for_each_entry(timer, &omap_timer_list, node) {
u32 l;

- l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
+ l = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
if (l & OMAP_TIMER_CTRL_ST) {
if (((omap_readl(MOD_CONF_CTRL_1) >> (i * 2)) & 0x03) == 0)
inputmask &= ~(1 << 1);
@@ -591,7 +583,7 @@ static int omap_dm_timer_start(struct omap_dm_timer *timer)

omap_dm_timer_enable(timer);

- l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
+ l = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
if (!(l & OMAP_TIMER_CTRL_ST)) {
l |= OMAP_TIMER_CTRL_ST;
omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
@@ -638,7 +630,7 @@ static int omap_dm_timer_set_match(struct omap_dm_timer *timer, int enable,
return -EINVAL;

omap_dm_timer_enable(timer);
- l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
+ l = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
if (enable)
l |= OMAP_TIMER_CTRL_CE;
else
@@ -659,7 +651,7 @@ static int omap_dm_timer_set_pwm(struct omap_dm_timer *timer, int def_on,
return -EINVAL;

omap_dm_timer_enable(timer);
- l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
+ l = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
l &= ~(OMAP_TIMER_CTRL_GPOCFG | OMAP_TIMER_CTRL_SCPWM |
OMAP_TIMER_CTRL_PT | (0x03 << 10) | OMAP_TIMER_CTRL_AR);
if (def_on)
@@ -683,7 +675,7 @@ static int omap_dm_timer_get_pwm_status(struct omap_dm_timer *timer)
return -EINVAL;

omap_dm_timer_enable(timer);
- l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
+ l = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
omap_dm_timer_disable(timer);

return l;
@@ -698,7 +690,7 @@ static int omap_dm_timer_set_prescaler(struct omap_dm_timer *timer,
return -EINVAL;

omap_dm_timer_enable(timer);
- l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
+ l = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
l &= ~(OMAP_TIMER_CTRL_PRE | (0x07 << 2));
if (prescaler >= 0) {
l |= OMAP_TIMER_CTRL_PRE;
@@ -743,7 +735,7 @@ static int omap_dm_timer_set_int_disable(struct omap_dm_timer *timer, u32 mask)
l = readl_relaxed(timer->irq_ena) & ~mask;

writel_relaxed(l, timer->irq_dis);
- l = omap_dm_timer_read_reg(timer, OMAP_TIMER_WAKEUP_EN_REG) & ~mask;
+ l = dmtimer_read(timer, OMAP_TIMER_WAKEUP_EN_REG) & ~mask;
omap_dm_timer_write_reg(timer, OMAP_TIMER_WAKEUP_EN_REG, l);

omap_dm_timer_disable(timer);
@@ -781,7 +773,7 @@ static unsigned int omap_dm_timer_read_counter(struct omap_dm_timer *timer)
return 0;
}

- return __omap_dm_timer_read_counter(timer, timer->posted);
+ return __omap_dm_timer_read_counter(timer);
}

static int omap_dm_timer_write_counter(struct omap_dm_timer *timer, unsigned int value)