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authorLinus Torvalds <torvalds@linux-foundation.org>2012-03-28 01:47:35 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2012-03-28 01:47:35 +0200
commit66f03c614c0902ccf7d6160459362a9352f33271 (patch)
treeb9a8864efe5aa7fc5c96cc5ccbeca41f5cd6f6a7 /drivers/clocksource
parentMerge tag 'drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc (diff)
parentMerge branch 'dt-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/tmli... (diff)
downloadlinux-66f03c614c0902ccf7d6160459362a9352f33271.tar.xz
linux-66f03c614c0902ccf7d6160459362a9352f33271.zip
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);