clocksource/drivers/timer-ti-dm: Save and restore timer TIOCP_CFG

As we are using cpu_pm to save and restore context, we must also save and
restore the timer sysconfig register TIOCP_CFG. This is needed because
we are not calling PM runtime functions at all with cpu_pm.

Fixes: b34677b0 ("clocksource/drivers/timer-ti-dm: Implement cpu_pm notifier for context save and restore")
Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: Adam Ford <aford173@gmail.com>
Cc: Andreas Kemnade <andreas@kemnade.info>
Cc: Lokesh Vutla <lokeshvutla@ti.com>
Cc: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20210415085506.56828-1-tony@atomide.com

drivers/clocksource/timer-ti-dm.c

@@ -78,6 +78,9 @@ static void omap_dm_timer_write_reg(struct omap_dm_timer *timer, u32 reg,
 
 static void omap_timer_restore_context(struct omap_dm_timer *timer)
 {
+	__omap_dm_timer_write(timer, OMAP_TIMER_OCP_CFG_OFFSET,
+			      timer->context.ocp_cfg, 0);
+
 	omap_dm_timer_write_reg(timer, OMAP_TIMER_WAKEUP_EN_REG,
 				timer->context.twer);
 	omap_dm_timer_write_reg(timer, OMAP_TIMER_COUNTER_REG,
@@ -95,6 +98,9 @@ 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 =

include/clocksource/timer-ti-dm.h

@@ -74,6 +74,7 @@
 #define OMAP_TIMER_ERRATA_I103_I767			0x80000000
 
 struct timer_regs {
+	u32 ocp_cfg;
 	u32 tidr;
 	u32 tier;
 	u32 twer;