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path: root/drivers/clocksource/tcb_clksrc.c
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Diffstat (limited to 'drivers/clocksource/tcb_clksrc.c')
-rw-r--r--drivers/clocksource/tcb_clksrc.c108
1 files changed, 68 insertions, 40 deletions
diff --git a/drivers/clocksource/tcb_clksrc.c b/drivers/clocksource/tcb_clksrc.c
index 138a12090149..bf68504da94a 100644
--- a/drivers/clocksource/tcb_clksrc.c
+++ b/drivers/clocksource/tcb_clksrc.c
@@ -9,7 +9,8 @@
#include <linux/err.h>
#include <linux/ioport.h>
#include <linux/io.h>
-#include <linux/platform_device.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
#include <linux/syscore_ops.h>
#include <soc/at91/atmel_tcb.h>
@@ -28,13 +29,6 @@
* 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.
@@ -112,7 +106,6 @@ void tc_clksrc_resume(struct clocksource *cs)
}
static struct clocksource clksrc = {
- .name = "tcb_clksrc",
.rating = 200,
.read = tc_get_cycles,
.mask = CLOCKSOURCE_MASK(32),
@@ -214,7 +207,6 @@ static int tc_next_event(unsigned long delta, struct clock_event_device *d)
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 */
@@ -330,39 +322,73 @@ static void __init tcb_setup_single_chan(struct atmel_tc *tc, int mck_divisor_id
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";
+static const u8 atmel_tcb_divisors[5] = { 2, 8, 32, 128, 0, };
+
+static const struct of_device_id atmel_tcb_of_match[] = {
+ { .compatible = "atmel,at91rm9200-tcb", .data = (void *)16, },
+ { .compatible = "atmel,at91sam9x5-tcb", .data = (void *)32, },
+ { /* sentinel */ }
+};
- struct platform_device *pdev;
- struct atmel_tc *tc;
+static int __init tcb_clksrc_init(struct device_node *node)
+{
+ struct atmel_tc tc;
struct clk *t0_clk;
+ const struct of_device_id *match;
u32 rate, divided_rate = 0;
int best_divisor_idx = -1;
int clk32k_divisor_idx = -1;
+ int bits;
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;
+ /* Protect against multiple calls */
+ if (tcaddr)
+ return 0;
+
+ tc.regs = of_iomap(node->parent, 0);
+ if (!tc.regs)
+ return -ENXIO;
+
+ t0_clk = of_clk_get_by_name(node->parent, "t0_clk");
+ if (IS_ERR(t0_clk))
+ return PTR_ERR(t0_clk);
+
+ tc.slow_clk = of_clk_get_by_name(node->parent, "slow_clk");
+ if (IS_ERR(tc.slow_clk))
+ return PTR_ERR(tc.slow_clk);
+
+ tc.clk[0] = t0_clk;
+ tc.clk[1] = of_clk_get_by_name(node->parent, "t1_clk");
+ if (IS_ERR(tc.clk[1]))
+ tc.clk[1] = t0_clk;
+ tc.clk[2] = of_clk_get_by_name(node->parent, "t2_clk");
+ if (IS_ERR(tc.clk[2]))
+ tc.clk[2] = t0_clk;
+
+ tc.irq[2] = of_irq_get(node->parent, 2);
+ if (tc.irq[2] <= 0) {
+ tc.irq[2] = of_irq_get(node->parent, 0);
+ if (tc.irq[2] <= 0)
+ return -EINVAL;
}
- tcaddr = tc->regs;
- pdev = tc->pdev;
- t0_clk = tc->clk[0];
+ match = of_match_node(atmel_tcb_of_match, node->parent);
+ bits = (uintptr_t)match->data;
+
+ for (i = 0; i < ARRAY_SIZE(tc.irq); i++)
+ writel(ATMEL_TC_ALL_IRQ, tc.regs + ATMEL_TC_REG(i, IDR));
+
ret = clk_prepare_enable(t0_clk);
if (ret) {
pr_debug("can't enable T0 clk\n");
- goto err_free_tc;
+ return ret;
}
/* 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];
+ for (i = 0; i < ARRAY_SIZE(atmel_tcb_divisors); i++) {
+ unsigned divisor = atmel_tcb_divisors[i];
unsigned tmp;
/* remember 32 KiHz clock for later */
@@ -381,27 +407,29 @@ static int __init tcb_clksrc_init(void)
best_divisor_idx = i;
}
-
- printk(bootinfo, clksrc.name, CONFIG_ATMEL_TCB_CLKSRC_BLOCK,
- divided_rate / 1000000,
+ clksrc.name = kbasename(node->parent->full_name);
+ clkevt.clkevt.name = kbasename(node->parent->full_name);
+ pr_debug("%s at %d.%03d MHz\n", clksrc.name, divided_rate / 1000000,
((divided_rate % 1000000) + 500) / 1000);
- if (tc->tcb_config && tc->tcb_config->counter_width == 32) {
+ tcaddr = tc.regs;
+
+ if (bits == 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);
+ tcb_setup_single_chan(&tc, best_divisor_idx);
} else {
- /* tclib will give us three clocks no matter what the
+ /* we have three clocks no matter what the
* underlying platform supports.
*/
- ret = clk_prepare_enable(tc->clk[1]);
+ 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);
+ tcb_setup_dual_chan(&tc, best_divisor_idx);
}
/* and away we go! */
@@ -410,7 +438,7 @@ static int __init tcb_clksrc_init(void)
goto err_disable_t1;
/* channel 2: periodic and oneshot timer support */
- ret = setup_clkevents(tc, clk32k_divisor_idx);
+ ret = setup_clkevents(&tc, clk32k_divisor_idx);
if (ret)
goto err_unregister_clksrc;
@@ -420,14 +448,14 @@ 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]);
+ if (bits != 32)
+ clk_disable_unprepare(tc.clk[1]);
err_disable_t0:
clk_disable_unprepare(t0_clk);
-err_free_tc:
- atmel_tc_free(tc);
+ tcaddr = NULL;
+
return ret;
}
-arch_initcall(tcb_clksrc_init);
+TIMER_OF_DECLARE(atmel_tcb_clksrc, "atmel,tcb-timer", tcb_clksrc_init);