[PATCH 54/58] clocksource/drivers: remove tcb_clksrc

Alexandre Belloni alexandre.belloni at free-electrons.com
Tue May 30 14:51:35 PDT 2017


AVR32 is now the last user of tcb_clksrc. It was removed in 4.12, remove
the driver.

Signed-off-by: Alexandre Belloni <alexandre.belloni at free-electrons.com>
---
 drivers/clocksource/Makefile     |   1 -
 drivers/clocksource/tcb_clksrc.c | 381 ---------------------------------------
 2 files changed, 382 deletions(-)
 delete mode 100644 drivers/clocksource/tcb_clksrc.c

diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index 53a0b40e0db2..68efe1fdeab3 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -2,7 +2,6 @@ obj-$(CONFIG_CLKSRC_PROBE)	+= clksrc-probe.o
 obj-$(CONFIG_CLKEVT_PROBE)	+= clkevt-probe.o
 obj-$(CONFIG_ATMEL_PIT)		+= timer-atmel-pit.o
 obj-$(CONFIG_ATMEL_ST)		+= timer-atmel-st.o
-obj-$(CONFIG_ATMEL_TCB_CLKSRC) += tcb_clksrc.o
 obj-$(CONFIG_ATMEL_ARM_TCB_CLKSRC)	+= timer-atmel-tcbclksrc.o
 obj-$(CONFIG_X86_PM_TIMER)	+= acpi_pm.o
 obj-$(CONFIG_SCx200HR_TIMER)	+= scx200_hrt.o
diff --git a/drivers/clocksource/tcb_clksrc.c b/drivers/clocksource/tcb_clksrc.c
deleted file mode 100644
index d4ca9962a759..000000000000
--- a/drivers/clocksource/tcb_clksrc.c
+++ /dev/null
@@ -1,381 +0,0 @@
-#include <linux/init.h>
-#include <linux/clocksource.h>
-#include <linux/clockchips.h>
-#include <linux/interrupt.h>
-#include <linux/irq.h>
-
-#include <linux/clk.h>
-#include <linux/err.h>
-#include <linux/ioport.h>
-#include <linux/io.h>
-#include <linux/platform_device.h>
-#include <linux/atmel_tc.h>
-
-
-/*
- * We're configured to use a specific TC block, one that's not hooked
- * up to external hardware, to provide a time solution:
- *
- *   - Two channels combine to create a free-running 32 bit counter
- *     with a base rate of 5+ MHz, packaged as a clocksource (with
- *     resolution better than 200 nsec).
- *   - Some chips support 32 bit counter. A single channel is used for
- *     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.
- *
- * A boot clocksource and clockevent source are also currently needed,
- * unless the relevant platforms (ARM/AT91, AVR32/AT32) are changed so
- * this code can be used when init_timers() is called, well before most
- * devices are set up.  (Some low end AT91 parts, which can run uClinux,
- * have only the timers in one TC block... they currently don't support
- * the tclib code, because of that initialization issue.)
- *
- * REVISIT behavior during system suspend states... we should disable
- * all clocks and save the power.  Easily done for clockevent devices,
- * but clocksources won't necessarily get the needed notifications.
- * For deeper system sleep states, this will be mandatory...
- */
-
-static void __iomem *tcaddr;
-
-static u64 tc_get_cycles(struct clocksource *cs)
-{
-	unsigned long	flags;
-	u32		lower, upper;
-
-	raw_local_irq_save(flags);
-	do {
-		upper = __raw_readl(tcaddr + ATMEL_TC_REG(1, CV));
-		lower = __raw_readl(tcaddr + ATMEL_TC_REG(0, CV));
-	} while (upper != __raw_readl(tcaddr + ATMEL_TC_REG(1, CV)));
-
-	raw_local_irq_restore(flags);
-	return (upper << 16) | lower;
-}
-
-static u64 tc_get_cycles32(struct clocksource *cs)
-{
-	return __raw_readl(tcaddr + ATMEL_TC_REG(0, CV));
-}
-
-static struct clocksource clksrc = {
-	.name           = "tcb_clksrc",
-	.rating         = 200,
-	.read           = tc_get_cycles,
-	.mask           = CLOCKSOURCE_MASK(32),
-	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
-};
-
-#ifdef CONFIG_GENERIC_CLOCKEVENTS
-
-struct tc_clkevt_device {
-	struct clock_event_device	clkevt;
-	struct clk			*clk;
-	void __iomem			*regs;
-};
-
-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 int tc_shutdown(struct clock_event_device *d)
-{
-	struct tc_clkevt_device *tcd = to_tc_clkevt(d);
-	void __iomem		*regs = tcd->regs;
-
-	__raw_writel(0xff, regs + ATMEL_TC_REG(2, IDR));
-	__raw_writel(ATMEL_TC_CLKDIS, regs + ATMEL_TC_REG(2, CCR));
-	if (!clockevent_state_detached(d))
-		clk_disable(tcd->clk);
-
-	return 0;
-}
-
-static int tc_set_oneshot(struct clock_event_device *d)
-{
-	struct tc_clkevt_device *tcd = to_tc_clkevt(d);
-	void __iomem		*regs = tcd->regs;
-
-	if (clockevent_state_oneshot(d) || clockevent_state_periodic(d))
-		tc_shutdown(d);
-
-	clk_enable(tcd->clk);
-
-	/* slow clock, count up to RC, then irq and stop */
-	__raw_writel(timer_clock | ATMEL_TC_CPCSTOP | ATMEL_TC_WAVE |
-		     ATMEL_TC_WAVESEL_UP_AUTO, regs + ATMEL_TC_REG(2, CMR));
-	__raw_writel(ATMEL_TC_CPCS, regs + ATMEL_TC_REG(2, IER));
-
-	/* set_next_event() configures and starts the timer */
-	return 0;
-}
-
-static int tc_set_periodic(struct clock_event_device *d)
-{
-	struct tc_clkevt_device *tcd = to_tc_clkevt(d);
-	void __iomem		*regs = tcd->regs;
-
-	if (clockevent_state_oneshot(d) || clockevent_state_periodic(d))
-		tc_shutdown(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);
-
-	/* slow clock, count up to RC, then irq and restart */
-	__raw_writel(timer_clock | ATMEL_TC_WAVE | ATMEL_TC_WAVESEL_UP_AUTO,
-		     regs + ATMEL_TC_REG(2, CMR));
-	__raw_writel((32768 + HZ / 2) / HZ, tcaddr + ATMEL_TC_REG(2, RC));
-
-	/* Enable clock and interrupts on RC compare */
-	__raw_writel(ATMEL_TC_CPCS, regs + ATMEL_TC_REG(2, IER));
-
-	/* go go gadget! */
-	__raw_writel(ATMEL_TC_CLKEN | ATMEL_TC_SWTRG, regs +
-		     ATMEL_TC_REG(2, CCR));
-	return 0;
-}
-
-static int tc_next_event(unsigned long delta, struct clock_event_device *d)
-{
-	__raw_writel(delta, tcaddr + ATMEL_TC_REG(2, RC));
-
-	/* go go gadget! */
-	__raw_writel(ATMEL_TC_CLKEN | ATMEL_TC_SWTRG,
-			tcaddr + ATMEL_TC_REG(2, CCR));
-	return 0;
-}
-
-static struct tc_clkevt_device clkevt = {
-	.clkevt	= {
-		.name			= "tc_clkevt",
-		.features		= CLOCK_EVT_FEAT_PERIODIC |
-					  CLOCK_EVT_FEAT_ONESHOT,
-		/* Should be lower than at91rm9200's system timer */
-		.rating			= 125,
-		.set_next_event		= tc_next_event,
-		.set_state_shutdown	= tc_shutdown,
-		.set_state_periodic	= tc_set_periodic,
-		.set_state_oneshot	= tc_set_oneshot,
-	},
-};
-
-static irqreturn_t ch2_irq(int irq, void *handle)
-{
-	struct tc_clkevt_device	*dev = handle;
-	unsigned int		sr;
-
-	sr = __raw_readl(dev->regs + ATMEL_TC_REG(2, SR));
-	if (sr & ATMEL_TC_CPCS) {
-		dev->clkevt.event_handler(&dev->clkevt);
-		return IRQ_HANDLED;
-	}
-
-	return IRQ_NONE;
-}
-
-static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx)
-{
-	int ret;
-	struct clk *t2_clk = tc->clk[2];
-	int irq = tc->irq[2];
-
-	ret = clk_prepare_enable(tc->slow_clk);
-	if (ret)
-		return ret;
-
-	/* try to enable t2 clk to avoid future errors in mode change */
-	ret = clk_prepare_enable(t2_clk);
-	if (ret) {
-		clk_disable_unprepare(tc->slow_clk);
-		return ret;
-	}
-
-	clk_disable(t2_clk);
-
-	clkevt.regs = tc->regs;
-	clkevt.clk = t2_clk;
-
-	timer_clock = clk32k_divisor_idx;
-
-	clkevt.clkevt.cpumask = cpumask_of(0);
-
-	ret = request_irq(irq, ch2_irq, IRQF_TIMER, "tc_clkevt", &clkevt);
-	if (ret) {
-		clk_unprepare(t2_clk);
-		clk_disable_unprepare(tc->slow_clk);
-		return ret;
-	}
-
-	clockevents_config_and_register(&clkevt.clkevt, 32768, 1, 0xffff);
-
-	return ret;
-}
-
-#else /* !CONFIG_GENERIC_CLOCKEVENTS */
-
-static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx)
-{
-	/* NOTHING */
-	return 0;
-}
-
-#endif
-
-static void __init tcb_setup_dual_chan(struct atmel_tc *tc, int mck_divisor_idx)
-{
-	/* channel 0:  waveform mode, input mclk/8, clock TIOA0 on overflow */
-	__raw_writel(mck_divisor_idx			/* likely divide-by-8 */
-			| ATMEL_TC_WAVE
-			| ATMEL_TC_WAVESEL_UP		/* free-run */
-			| ATMEL_TC_ACPA_SET		/* TIOA0 rises at 0 */
-			| ATMEL_TC_ACPC_CLEAR,		/* (duty cycle 50%) */
-			tcaddr + ATMEL_TC_REG(0, CMR));
-	__raw_writel(0x0000, tcaddr + ATMEL_TC_REG(0, RA));
-	__raw_writel(0x8000, tcaddr + ATMEL_TC_REG(0, RC));
-	__raw_writel(0xff, tcaddr + ATMEL_TC_REG(0, IDR));	/* no irqs */
-	__raw_writel(ATMEL_TC_CLKEN, tcaddr + ATMEL_TC_REG(0, CCR));
-
-	/* channel 1:  waveform mode, input TIOA0 */
-	__raw_writel(ATMEL_TC_XC1			/* input: TIOA0 */
-			| ATMEL_TC_WAVE
-			| ATMEL_TC_WAVESEL_UP,		/* free-run */
-			tcaddr + ATMEL_TC_REG(1, CMR));
-	__raw_writel(0xff, tcaddr + ATMEL_TC_REG(1, IDR));	/* no irqs */
-	__raw_writel(ATMEL_TC_CLKEN, tcaddr + ATMEL_TC_REG(1, CCR));
-
-	/* chain channel 0 to channel 1*/
-	__raw_writel(ATMEL_TC_TC1XC1S_TIOA0, tcaddr + ATMEL_TC_BMR);
-	/* then reset all the timers */
-	__raw_writel(ATMEL_TC_SYNC, tcaddr + ATMEL_TC_BCR);
-}
-
-static void __init tcb_setup_single_chan(struct atmel_tc *tc, int mck_divisor_idx)
-{
-	/* channel 0:  waveform mode, input mclk/8 */
-	__raw_writel(mck_divisor_idx			/* likely divide-by-8 */
-			| ATMEL_TC_WAVE
-			| ATMEL_TC_WAVESEL_UP,		/* free-run */
-			tcaddr + ATMEL_TC_REG(0, CMR));
-	__raw_writel(0xff, tcaddr + ATMEL_TC_REG(0, IDR));	/* no irqs */
-	__raw_writel(ATMEL_TC_CLKEN, tcaddr + ATMEL_TC_REG(0, CCR));
-
-	/* then reset all the timers */
-	__raw_writel(ATMEL_TC_SYNC, tcaddr + ATMEL_TC_BCR);
-}
-
-static int __init tcb_clksrc_init(void)
-{
-	static char bootinfo[] __initdata
-		= KERN_DEBUG "%s: tc%d at %d.%03d MHz\n";
-
-	struct platform_device *pdev;
-	struct atmel_tc *tc;
-	struct clk *t0_clk;
-	u32 rate, divided_rate = 0;
-	int best_divisor_idx = -1;
-	int clk32k_divisor_idx = -1;
-	int i;
-	int ret;
-
-	tc = atmel_tc_alloc(CONFIG_ATMEL_TCB_CLKSRC_BLOCK);
-	if (!tc) {
-		pr_debug("can't alloc TC for clocksource\n");
-		return -ENODEV;
-	}
-	tcaddr = tc->regs;
-	pdev = tc->pdev;
-
-	t0_clk = tc->clk[0];
-	ret = clk_prepare_enable(t0_clk);
-	if (ret) {
-		pr_debug("can't enable T0 clk\n");
-		goto err_free_tc;
-	}
-
-	/* How fast will we be counting?  Pick something over 5 MHz.  */
-	rate = (u32) clk_get_rate(t0_clk);
-	for (i = 0; i < 5; i++) {
-		unsigned divisor = atmel_tc_divisors[i];
-		unsigned tmp;
-
-		/* remember 32 KiHz clock for later */
-		if (!divisor) {
-			clk32k_divisor_idx = i;
-			continue;
-		}
-
-		tmp = rate / divisor;
-		pr_debug("TC: %u / %-3u [%d] --> %u\n", rate, divisor, i, tmp);
-		if (best_divisor_idx > 0) {
-			if (tmp < 5 * 1000 * 1000)
-				continue;
-		}
-		divided_rate = tmp;
-		best_divisor_idx = i;
-	}
-
-
-	printk(bootinfo, clksrc.name, CONFIG_ATMEL_TCB_CLKSRC_BLOCK,
-			divided_rate / 1000000,
-			((divided_rate + 500000) % 1000000) / 1000);
-
-	if (tc->tcb_config && tc->tcb_config->counter_width == 32) {
-		/* use apropriate function to read 32 bit counter */
-		clksrc.read = tc_get_cycles32;
-		/* setup ony channel 0 */
-		tcb_setup_single_chan(tc, best_divisor_idx);
-	} else {
-		/* tclib will give us three clocks no matter what the
-		 * underlying platform supports.
-		 */
-		ret = clk_prepare_enable(tc->clk[1]);
-		if (ret) {
-			pr_debug("can't enable T1 clk\n");
-			goto err_disable_t0;
-		}
-		/* setup both channel 0 & 1 */
-		tcb_setup_dual_chan(tc, best_divisor_idx);
-	}
-
-	/* and away we go! */
-	ret = clocksource_register_hz(&clksrc, divided_rate);
-	if (ret)
-		goto err_disable_t1;
-
-	/* channel 2:  periodic and oneshot timer support */
-	ret = setup_clkevents(tc, clk32k_divisor_idx);
-	if (ret)
-		goto err_unregister_clksrc;
-
-	return 0;
-
-err_unregister_clksrc:
-	clocksource_unregister(&clksrc);
-
-err_disable_t1:
-	if (!tc->tcb_config || tc->tcb_config->counter_width != 32)
-		clk_disable_unprepare(tc->clk[1]);
-
-err_disable_t0:
-	clk_disable_unprepare(t0_clk);
-
-err_free_tc:
-	atmel_tc_free(tc);
-	return ret;
-}
-arch_initcall(tcb_clksrc_init);
-- 
2.11.0




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