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authorLinus Torvalds <torvalds@linux-foundation.org>2012-03-27 16:47:35 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-03-27 16:47:35 -0700
commit66f03c614c0902ccf7d6160459362a9352f33271 (patch)
treeb9a8864efe5aa7fc5c96cc5ccbeca41f5cd6f6a7 /drivers/clocksource
parent34800598b2eebe061445216473b1e4c2ff5cba99 (diff)
parentcdc3df6f44f72c5924a16a47e1663c3fb0e57820 (diff)
downloadlinux-66f03c614c0902ccf7d6160459362a9352f33271.tar.gz
Merge tag 'dt' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull "ARM: device tree work" from Arnd Bergmann:
 "Most of these patches convert code from using static platform data to
  describing the hardware in the device tree.  This is only the first
  half of the changes for v3.4 because a lot of patches for this topic
  came in the last week before the merge window.

  Signed-off-by: Arnd Bergmann <arnd@arndb.de>"

Fix up trivial conflicts in arch/arm/mach-vexpress/{Kconfig,core.h}

* tag 'dt' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (86 commits)
  Document: devicetree: add OF documents for arch-mmp
  ARM: dts: append DTS file of pxa168
  ARM: mmp: append OF support on pxa168
  ARM: mmp: enable rtc clk in pxa168
  i2c: pxa: add OF support
  serial: pxa: add OF support
  arm/dts: mt_ventoux: very basic support for TeeJet Mt.Ventoux board
  ARM: OMAP2+: Remove extra ifdefs for board-generic
  ARM: OMAP2+: Fix build error when only ARCH_OMAP2/3 or 4 is selected
  ASoC: DT: Add digital microphone binding to PAZ00 board.
  ARM: dt: Add ARM PMU to tegra*.dtsi
  ARM: at91: at91sam9x5cm/dt: add leds support
  ARM: at91: usb_a9g20/dt: add gpio-keys support
  ARM: at91: at91sam9m10g45ek/dt: add gpio-keys support
  ARM: at91: at91sam9m10g45ek/dt: add leds support
  ARM: at91: usb_a9g20/dt: add leds support
  ARM: at91/pio: add new PIO3 features
  ARM: at91: add sam9_smc.o to at91sam9x5 build
  ARM: at91/tc/clocksource: Add 32 bit variant to Timer Counter
  ARM: at91/tc: add device tree support to atmel_tclib
  ...
Diffstat (limited to 'drivers/clocksource')
-rw-r--r--drivers/clocksource/tcb_clksrc.c90
1 files changed, 62 insertions, 28 deletions
diff --git a/drivers/clocksource/tcb_clksrc.c b/drivers/clocksource/tcb_clksrc.c
index 55d0f95f82f9..32cb929b8eb6 100644
--- a/drivers/clocksource/tcb_clksrc.c
+++ b/drivers/clocksource/tcb_clksrc.c
@@ -19,6 +19,8 @@
  *   - 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
@@ -54,6 +56,11 @@ static cycle_t tc_get_cycles(struct clocksource *cs)
 	return (upper << 16) | lower;
 }
 
+static cycle_t tc_get_cycles32(struct clocksource *cs)
+{
+	return __raw_readl(tcaddr + ATMEL_TC_REG(0, CV));
+}
+
 static struct clocksource clksrc = {
 	.name           = "tcb_clksrc",
 	.rating         = 200,
@@ -209,6 +216,48 @@ static void __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx)
 
 #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
@@ -260,34 +309,19 @@ static int __init tcb_clksrc_init(void)
 			divided_rate / 1000000,
 			((divided_rate + 500000) % 1000000) / 1000);
 
-	/* tclib will give us three clocks no matter what the
-	 * underlying platform supports.
-	 */
-	clk_enable(tc->clk[1]);
-
-	/* channel 0:  waveform mode, input mclk/8, clock TIOA0 on overflow */
-	__raw_writel(best_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, then reset all the timers */
-	__raw_writel(ATMEL_TC_TC1XC1S_TIOA0, tcaddr + ATMEL_TC_BMR);
-	__raw_writel(ATMEL_TC_SYNC, tcaddr + ATMEL_TC_BCR);
+	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.
+		 */
+		clk_enable(tc->clk[1]);
+		/* setup both channel 0 & 1 */
+		tcb_setup_dual_chan(tc, best_divisor_idx);
+	}
 
 	/* and away we go! */
 	clocksource_register_hz(&clksrc, divided_rate);