clocksource/drivers/imx-tpm: Add different counter width support

Different TPM modules have different width counters which is 16-bit or 32-bit,
the counter width can be read from TPM_PARAM register bit[23:16], this patch
adds dynamic check for counter width to support both 16-bit and 32-bit TPM
modules.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
This commit is contained in:
Anson Huang 2018-03-28 11:22:38 +08:00 committed by Daniel Lezcano
parent 506a7be93f
commit 0136c741ff

View File

@ -17,9 +17,13 @@
#include <linux/of_irq.h>
#include <linux/sched_clock.h>
#define TPM_PARAM 0x4
#define TPM_PARAM_WIDTH_SHIFT 16
#define TPM_PARAM_WIDTH_MASK (0xff << 16)
#define TPM_SC 0x10
#define TPM_SC_CMOD_INC_PER_CNT (0x1 << 3)
#define TPM_SC_CMOD_DIV_DEFAULT 0x3
#define TPM_SC_CMOD_DIV_MAX 0x7
#define TPM_SC_TOF_MASK (0x1 << 7)
#define TPM_CNT 0x14
#define TPM_MOD 0x18
@ -33,6 +37,8 @@
#define TPM_C0SC_CHF_MASK (0x1 << 7)
#define TPM_C0V 0x24
static int counter_width;
static int rating;
static void __iomem *timer_base;
static struct clock_event_device clockevent_tpm;
@ -85,10 +91,11 @@ static int __init tpm_clocksource_init(unsigned long rate)
tpm_delay_timer.freq = rate;
register_current_timer_delay(&tpm_delay_timer);
sched_clock_register(tpm_read_sched_clock, 32, rate);
sched_clock_register(tpm_read_sched_clock, counter_width, rate);
return clocksource_mmio_init(timer_base + TPM_CNT, "imx-tpm",
rate, 200, 32, clocksource_mmio_readl_up);
rate, rating, counter_width,
clocksource_mmio_readl_up);
}
static int tpm_set_next_event(unsigned long delta,
@ -141,7 +148,6 @@ static struct clock_event_device clockevent_tpm = {
.set_state_oneshot = tpm_set_state_oneshot,
.set_next_event = tpm_set_next_event,
.set_state_shutdown = tpm_set_state_shutdown,
.rating = 200,
};
static int __init tpm_clockevent_init(unsigned long rate, int irq)
@ -151,10 +157,11 @@ static int __init tpm_clockevent_init(unsigned long rate, int irq)
ret = request_irq(irq, tpm_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
"i.MX7ULP TPM Timer", &clockevent_tpm);
clockevent_tpm.rating = rating;
clockevent_tpm.cpumask = cpumask_of(0);
clockevent_tpm.irq = irq;
clockevents_config_and_register(&clockevent_tpm,
rate, 300, 0xfffffffe);
clockevents_config_and_register(&clockevent_tpm, rate, 300,
GENMASK(counter_width - 1, 1));
return ret;
}
@ -199,6 +206,11 @@ static int __init tpm_timer_init(struct device_node *np)
goto err_per_clk_enable;
}
counter_width = (readl(timer_base + TPM_PARAM) & TPM_PARAM_WIDTH_MASK)
>> TPM_PARAM_WIDTH_SHIFT;
/* use rating 200 for 32-bit counter and 150 for 16-bit counter */
rating = counter_width == 0x20 ? 200 : 150;
/*
* Initialize tpm module to a known state
* 1) Counter disabled
@ -215,12 +227,17 @@ static int __init tpm_timer_init(struct device_node *np)
/* CHF is W1C */
writel(TPM_C0SC_CHF_MASK, timer_base + TPM_C0SC);
/* increase per cnt, div 8 by default */
writel(TPM_SC_CMOD_INC_PER_CNT | TPM_SC_CMOD_DIV_DEFAULT,
/*
* increase per cnt,
* div 8 for 32-bit counter and div 128 for 16-bit counter
*/
writel(TPM_SC_CMOD_INC_PER_CNT |
(counter_width == 0x20 ?
TPM_SC_CMOD_DIV_DEFAULT : TPM_SC_CMOD_DIV_MAX),
timer_base + TPM_SC);
/* set MOD register to maximum for free running mode */
writel(0xffffffff, timer_base + TPM_MOD);
writel(GENMASK(counter_width - 1, 0), timer_base + TPM_MOD);
rate = clk_get_rate(per) >> 3;
ret = tpm_clocksource_init(rate);