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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:38 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:38 +0000
commit08b74a000942a380fe028845f92cd3a0dee827d5 (patch)
treeaa78b4e12607c3e1fcce8d5cc42df4330792f118 /debian/patches-rt/0030-clocksource-TCLIB-Allow-higher-clock-rates-for-clock.patch
parentAdding upstream version 4.19.249. (diff)
downloadlinux-debian.tar.xz
linux-debian.zip
Adding debian version 4.19.249-2.debian/4.19.249-2debian
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'debian/patches-rt/0030-clocksource-TCLIB-Allow-higher-clock-rates-for-clock.patch')
-rw-r--r--debian/patches-rt/0030-clocksource-TCLIB-Allow-higher-clock-rates-for-clock.patch170
1 files changed, 170 insertions, 0 deletions
diff --git a/debian/patches-rt/0030-clocksource-TCLIB-Allow-higher-clock-rates-for-clock.patch b/debian/patches-rt/0030-clocksource-TCLIB-Allow-higher-clock-rates-for-clock.patch
new file mode 100644
index 000000000..92ac4b1e3
--- /dev/null
+++ b/debian/patches-rt/0030-clocksource-TCLIB-Allow-higher-clock-rates-for-clock.patch
@@ -0,0 +1,170 @@
+From 785e3ab127a7476bb4da35910092b0d2fd767a47 Mon Sep 17 00:00:00 2001
+From: Benedikt Spranger <b.spranger@linutronix.de>
+Date: Mon, 8 Mar 2010 18:57:04 +0100
+Subject: [PATCH 030/347] clocksource: TCLIB: Allow higher clock rates for
+ clock events
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.246-rt110.tar.xz
+
+As default the TCLIB uses the 32KiHz base clock rate for clock events.
+Add a compile time selection to allow higher clock resulution.
+
+(fixed up by Sami Pietikäinen <Sami.Pietikainen@wapice.com>)
+
+Signed-off-by: Benedikt Spranger <b.spranger@linutronix.de>
+Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
+---
+ drivers/clocksource/tcb_clksrc.c | 36 +++++++++++++++++++-------------
+ drivers/misc/Kconfig | 12 +++++++++--
+ 2 files changed, 31 insertions(+), 17 deletions(-)
+
+diff --git a/drivers/clocksource/tcb_clksrc.c b/drivers/clocksource/tcb_clksrc.c
+index de6baf564dfe..ba15242a6066 100644
+--- a/drivers/clocksource/tcb_clksrc.c
++++ b/drivers/clocksource/tcb_clksrc.c
+@@ -25,8 +25,7 @@
+ * this 32 bit free-running counter. the second channel is not used.
+ *
+ * - The third channel may be used to provide a 16-bit clockevent
+- * source, used in either periodic or oneshot mode. This runs
+- * at 32 KiHZ, and can handle delays of up to two seconds.
++ * source, used in either periodic or oneshot mode.
+ *
+ * A boot clocksource and clockevent source are also currently needed,
+ * unless the relevant platforms (ARM/AT91, AVR32/AT32) are changed so
+@@ -127,6 +126,7 @@ struct tc_clkevt_device {
+ struct clock_event_device clkevt;
+ struct clk *clk;
+ bool clk_enabled;
++ u32 freq;
+ void __iomem *regs;
+ };
+
+@@ -135,13 +135,6 @@ static struct tc_clkevt_device *to_tc_clkevt(struct clock_event_device *clkevt)
+ return container_of(clkevt, struct tc_clkevt_device, clkevt);
+ }
+
+-/* For now, we always use the 32K clock ... this optimizes for NO_HZ,
+- * because using one of the divided clocks would usually mean the
+- * tick rate can never be less than several dozen Hz (vs 0.5 Hz).
+- *
+- * A divided clock could be good for high resolution timers, since
+- * 30.5 usec resolution can seem "low".
+- */
+ static u32 timer_clock;
+
+ static void tc_clk_disable(struct clock_event_device *d)
+@@ -191,7 +184,7 @@ static int tc_set_oneshot(struct clock_event_device *d)
+
+ tc_clk_enable(d);
+
+- /* slow clock, count up to RC, then irq and stop */
++ /* count up to RC, then irq and stop */
+ writel(timer_clock | ATMEL_TC_CPCSTOP | ATMEL_TC_WAVE |
+ ATMEL_TC_WAVESEL_UP_AUTO, regs + ATMEL_TC_REG(2, CMR));
+ writel(ATMEL_TC_CPCS, regs + ATMEL_TC_REG(2, IER));
+@@ -213,10 +206,10 @@ static int tc_set_periodic(struct clock_event_device *d)
+ */
+ tc_clk_enable(d);
+
+- /* slow clock, count up to RC, then irq and restart */
++ /* count up to RC, then irq and restart */
+ writel(timer_clock | ATMEL_TC_WAVE | ATMEL_TC_WAVESEL_UP_AUTO,
+ regs + ATMEL_TC_REG(2, CMR));
+- writel((32768 + HZ / 2) / HZ, tcaddr + ATMEL_TC_REG(2, RC));
++ writel((tcd->freq + HZ / 2) / HZ, tcaddr + ATMEL_TC_REG(2, RC));
+
+ /* Enable clock and interrupts on RC compare */
+ writel(ATMEL_TC_CPCS, regs + ATMEL_TC_REG(2, IER));
+@@ -243,7 +236,11 @@ static struct tc_clkevt_device clkevt = {
+ .features = CLOCK_EVT_FEAT_PERIODIC |
+ CLOCK_EVT_FEAT_ONESHOT,
+ /* Should be lower than at91rm9200's system timer */
++#ifdef CONFIG_ATMEL_TCB_CLKSRC_USE_SLOW_CLOCK
+ .rating = 125,
++#else
++ .rating = 200,
++#endif
+ .set_next_event = tc_next_event,
+ .set_state_shutdown = tc_shutdown_clk_off,
+ .set_state_periodic = tc_set_periodic,
+@@ -265,8 +262,9 @@ static irqreturn_t ch2_irq(int irq, void *handle)
+ return IRQ_NONE;
+ }
+
+-static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx)
++static int __init setup_clkevents(struct atmel_tc *tc, int divisor_idx)
+ {
++ unsigned divisor = atmel_tc_divisors[divisor_idx];
+ int ret;
+ struct clk *t2_clk = tc->clk[2];
+ int irq = tc->irq[2];
+@@ -287,7 +285,11 @@ static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx)
+ clkevt.regs = tc->regs;
+ clkevt.clk = t2_clk;
+
+- timer_clock = clk32k_divisor_idx;
++ timer_clock = divisor_idx;
++ if (!divisor)
++ clkevt.freq = 32768;
++ else
++ clkevt.freq = clk_get_rate(t2_clk) / divisor;
+
+ clkevt.clkevt.cpumask = cpumask_of(0);
+
+@@ -298,7 +300,7 @@ static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx)
+ return ret;
+ }
+
+- clockevents_config_and_register(&clkevt.clkevt, 32768, 1, 0xffff);
++ clockevents_config_and_register(&clkevt.clkevt, clkevt.freq, 1, 0xffff);
+
+ return ret;
+ }
+@@ -435,7 +437,11 @@ static int __init tcb_clksrc_init(void)
+ goto err_disable_t1;
+
+ /* channel 2: periodic and oneshot timer support */
++#ifdef CONFIG_ATMEL_TCB_CLKSRC_USE_SLOW_CLOCK
+ ret = setup_clkevents(tc, clk32k_divisor_idx);
++#else
++ ret = setup_clkevents(tc, best_divisor_idx);
++#endif
+ if (ret)
+ goto err_unregister_clksrc;
+
+diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
+index 3726eacdf65d..0900dec7ec04 100644
+--- a/drivers/misc/Kconfig
++++ b/drivers/misc/Kconfig
+@@ -69,8 +69,7 @@ config ATMEL_TCB_CLKSRC
+ are combined to make a single 32-bit timer.
+
+ When GENERIC_CLOCKEVENTS is defined, the third timer channel
+- may be used as a clock event device supporting oneshot mode
+- (delays of up to two seconds) based on the 32 KiHz clock.
++ may be used as a clock event device supporting oneshot mode.
+
+ config ATMEL_TCB_CLKSRC_BLOCK
+ int
+@@ -83,6 +82,15 @@ config ATMEL_TCB_CLKSRC_BLOCK
+ TC can be used for other purposes, such as PWM generation and
+ interval timing.
+
++config ATMEL_TCB_CLKSRC_USE_SLOW_CLOCK
++ bool "TC Block use 32 KiHz clock"
++ depends on ATMEL_TCB_CLKSRC
++ default y
++ help
++ Select this to use 32 KiHz base clock rate as TC block clock
++ source for clock events.
++
++
+ config DUMMY_IRQ
+ tristate "Dummy IRQ handler"
+ default n
+--
+2.36.1
+