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authorIngo Molnar <mingo@kernel.org>2012-04-14 13:18:27 +0200
committerIngo Molnar <mingo@kernel.org>2012-04-14 13:19:04 +0200
commit6ac1ef482d7ae0c690f1640bf6eb818ff9a2d91e (patch)
tree021cc9f6b477146fcebe6f3be4752abfa2ba18a9 /drivers/clocksource/tcb_clksrc.c
parent682968e0c425c60f0dde37977e5beb2b12ddc4cc (diff)
parenta385ec4f11bdcf81af094c03e2444ee9b7fad2e5 (diff)
Merge branch 'perf/core' into perf/uprobes
Merge in latest upstream (and the latest perf development tree), to prepare for tooling changes, and also to pick up v3.4 MM changes that the uprobes code needs to take care of. Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'drivers/clocksource/tcb_clksrc.c')
-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 55d0f95f82f..32cb929b8eb 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);