diff options
Diffstat (limited to 'debian/patches-rt/0029-arm-at91-do-not-disable-enable-clocks-in-a-row.patch')
| -rw-r--r-- | debian/patches-rt/0029-arm-at91-do-not-disable-enable-clocks-in-a-row.patch | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/debian/patches-rt/0029-arm-at91-do-not-disable-enable-clocks-in-a-row.patch b/debian/patches-rt/0029-arm-at91-do-not-disable-enable-clocks-in-a-row.patch new file mode 100644 index 000000000..8bf2d54e0 --- /dev/null +++ b/debian/patches-rt/0029-arm-at91-do-not-disable-enable-clocks-in-a-row.patch @@ -0,0 +1,98 @@ +From 61b697c120be1e50542dfa879ebb522bf834b8d2 Mon Sep 17 00:00:00 2001 +From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +Date: Wed, 9 Mar 2016 10:51:06 +0100 +Subject: [PATCH 029/347] arm: at91: do not disable/enable clocks in a row +Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.246-rt110.tar.xz + +Currently the driver will disable the clock and enable it one line later +if it is switching from periodic mode into one shot. +This can be avoided and causes a needless warning on -RT. + +Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +--- + drivers/clocksource/tcb_clksrc.c | 33 ++++++++++++++++++++++++++++---- + 1 file changed, 29 insertions(+), 4 deletions(-) + +diff --git a/drivers/clocksource/tcb_clksrc.c b/drivers/clocksource/tcb_clksrc.c +index 43f4d5c4d6fa..de6baf564dfe 100644 +--- a/drivers/clocksource/tcb_clksrc.c ++++ b/drivers/clocksource/tcb_clksrc.c +@@ -126,6 +126,7 @@ static struct clocksource clksrc = { + struct tc_clkevt_device { + struct clock_event_device clkevt; + struct clk *clk; ++ bool clk_enabled; + void __iomem *regs; + }; + +@@ -143,6 +144,24 @@ static struct tc_clkevt_device *to_tc_clkevt(struct clock_event_device *clkevt) + */ + static u32 timer_clock; + ++static void tc_clk_disable(struct clock_event_device *d) ++{ ++ struct tc_clkevt_device *tcd = to_tc_clkevt(d); ++ ++ clk_disable(tcd->clk); ++ tcd->clk_enabled = false; ++} ++ ++static void tc_clk_enable(struct clock_event_device *d) ++{ ++ struct tc_clkevt_device *tcd = to_tc_clkevt(d); ++ ++ if (tcd->clk_enabled) ++ return; ++ clk_enable(tcd->clk); ++ tcd->clk_enabled = true; ++} ++ + static int tc_shutdown(struct clock_event_device *d) + { + struct tc_clkevt_device *tcd = to_tc_clkevt(d); +@@ -150,8 +169,14 @@ static int tc_shutdown(struct clock_event_device *d) + + writel(0xff, regs + ATMEL_TC_REG(2, IDR)); + writel(ATMEL_TC_CLKDIS, regs + ATMEL_TC_REG(2, CCR)); ++ return 0; ++} ++ ++static int tc_shutdown_clk_off(struct clock_event_device *d) ++{ ++ tc_shutdown(d); + if (!clockevent_state_detached(d)) +- clk_disable(tcd->clk); ++ tc_clk_disable(d); + + return 0; + } +@@ -164,7 +189,7 @@ static int tc_set_oneshot(struct clock_event_device *d) + if (clockevent_state_oneshot(d) || clockevent_state_periodic(d)) + tc_shutdown(d); + +- clk_enable(tcd->clk); ++ tc_clk_enable(d); + + /* slow clock, count up to RC, then irq and stop */ + writel(timer_clock | ATMEL_TC_CPCSTOP | ATMEL_TC_WAVE | +@@ -186,7 +211,7 @@ static int tc_set_periodic(struct clock_event_device *d) + /* By not making the gentime core emulate periodic mode on top + * of oneshot, we get lower overhead and improved accuracy. + */ +- clk_enable(tcd->clk); ++ tc_clk_enable(d); + + /* slow clock, count up to RC, then irq and restart */ + writel(timer_clock | ATMEL_TC_WAVE | ATMEL_TC_WAVESEL_UP_AUTO, +@@ -220,7 +245,7 @@ static struct tc_clkevt_device clkevt = { + /* Should be lower than at91rm9200's system timer */ + .rating = 125, + .set_next_event = tc_next_event, +- .set_state_shutdown = tc_shutdown, ++ .set_state_shutdown = tc_shutdown_clk_off, + .set_state_periodic = tc_set_periodic, + .set_state_oneshot = tc_set_oneshot, + }, +-- +2.36.1 + |