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Diffstat (limited to 'arch/arm/cpu/armv7m/stm32f4/timer.c')
-rw-r--r--arch/arm/cpu/armv7m/stm32f4/timer.c118
1 files changed, 118 insertions, 0 deletions
diff --git a/arch/arm/cpu/armv7m/stm32f4/timer.c b/arch/arm/cpu/armv7m/stm32f4/timer.c
new file mode 100644
index 0000000000..102ae6d960
--- /dev/null
+++ b/arch/arm/cpu/armv7m/stm32f4/timer.c
@@ -0,0 +1,118 @@
+/*
+ * (C) Copyright 2015
+ * Kamil Lulko, <rev13@wp.pl>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/armv7m.h>
+#include <asm/arch/stm32.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define STM32_TIM2_BASE (STM32_APB1PERIPH_BASE + 0x0000)
+
+#define RCC_APB1ENR_TIM2EN (1 << 0)
+
+struct stm32_tim2_5 {
+ u32 cr1;
+ u32 cr2;
+ u32 smcr;
+ u32 dier;
+ u32 sr;
+ u32 egr;
+ u32 ccmr1;
+ u32 ccmr2;
+ u32 ccer;
+ u32 cnt;
+ u32 psc;
+ u32 arr;
+ u32 reserved1;
+ u32 ccr1;
+ u32 ccr2;
+ u32 ccr3;
+ u32 ccr4;
+ u32 reserved2;
+ u32 dcr;
+ u32 dmar;
+ u32 or;
+};
+
+#define TIM_CR1_CEN (1 << 0)
+
+#define TIM_EGR_UG (1 << 0)
+
+int timer_init(void)
+{
+ struct stm32_tim2_5 *tim = (struct stm32_tim2_5 *)STM32_TIM2_BASE;
+
+ setbits_le32(&STM32_RCC->apb1enr, RCC_APB1ENR_TIM2EN);
+
+ if (clock_get(CLOCK_AHB) == clock_get(CLOCK_APB1))
+ writel((clock_get(CLOCK_APB1) / CONFIG_SYS_HZ_CLOCK) - 1,
+ &tim->psc);
+ else
+ writel(((clock_get(CLOCK_APB1) * 2) / CONFIG_SYS_HZ_CLOCK) - 1,
+ &tim->psc);
+
+ writel(0xFFFFFFFF, &tim->arr);
+ writel(TIM_CR1_CEN, &tim->cr1);
+ setbits_le32(&tim->egr, TIM_EGR_UG);
+
+ gd->arch.tbl = 0;
+ gd->arch.tbu = 0;
+ gd->arch.lastinc = 0;
+
+ return 0;
+}
+
+ulong get_timer(ulong base)
+{
+ return (get_ticks() / (CONFIG_SYS_HZ_CLOCK / CONFIG_SYS_HZ)) - base;
+}
+
+unsigned long long get_ticks(void)
+{
+ struct stm32_tim2_5 *tim = (struct stm32_tim2_5 *)STM32_TIM2_BASE;
+ u32 now;
+
+ now = readl(&tim->cnt);
+
+ if (now >= gd->arch.lastinc)
+ gd->arch.tbl += (now - gd->arch.lastinc);
+ else
+ gd->arch.tbl += (0xFFFFFFFF - gd->arch.lastinc) + now;
+
+ gd->arch.lastinc = now;
+
+ return gd->arch.tbl;
+}
+
+void reset_timer(void)
+{
+ struct stm32_tim2_5 *tim = (struct stm32_tim2_5 *)STM32_TIM2_BASE;
+
+ gd->arch.lastinc = readl(&tim->cnt);
+ gd->arch.tbl = 0;
+}
+
+/* delay x useconds */
+void __udelay(ulong usec)
+{
+ unsigned long long start;
+
+ start = get_ticks(); /* get current timestamp */
+ while ((get_ticks() - start) < usec)
+ ; /* loop till time has passed */
+}
+
+/*
+ * This function is derived from PowerPC code (timebase clock frequency).
+ * On ARM it returns the number of timer ticks per second.
+ */
+ulong get_tbclk(void)
+{
+ return CONFIG_SYS_HZ_CLOCK;
+}