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[U-Boot,v6] imx: system counter driver for imx7d and mx6ul

Message ID 1440540022-6705-1-git-send-email-aalonso@freescale.com
State Superseded
Delegated to: Stefano Babic
Headers show

Commit Message

Adrian Alonso Aug. 25, 2015, 10 p.m. UTC
Add system counter driver for imx7d and mx6ul
imx7 and imx6ul supports system counter timer as well as
GPT timer (arch/arm/imx-common/timer.c); The default for
imx7 is systemcounter timer.

Signed-off-by: Adrian Alonso <aalonso@freescale.com>
Signed-off-by: Ye.Li <B37916@freescale.com>
---
Changes for V2 to V5: Resend
Changes for V6:
- Update comiit log description
- Drop change set on mx6_common.h

 arch/arm/imx-common/syscounter.c             | 126 +++++++++++++++++++++++++++
 arch/arm/include/asm/imx-common/syscounter.h |  29 ++++++
 2 files changed, 155 insertions(+)
 create mode 100644 arch/arm/imx-common/syscounter.c
 create mode 100644 arch/arm/include/asm/imx-common/syscounter.h
diff mbox

Patch

diff --git a/arch/arm/imx-common/syscounter.c b/arch/arm/imx-common/syscounter.c
new file mode 100644
index 0000000..e00fef2
--- /dev/null
+++ b/arch/arm/imx-common/syscounter.c
@@ -0,0 +1,126 @@ 
+/*
+ * Copyright (C) 2015 Freescale Semiconductor, Inc.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ *
+ * The file use ls102xa/timer.c as a reference.
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <div64.h>
+#include <asm/arch/imx-regs.h>
+#include <asm/arch/sys_proto.h>
+#include <asm/imx-common/syscounter.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/*
+ * This function is intended for SHORT delays only.
+ * It will overflow at around 10 seconds @ 400MHz,
+ * or 20 seconds @ 200MHz.
+ */
+unsigned long usec2ticks(unsigned long usec)
+{
+	ulong ticks;
+
+	if (usec < 1000)
+		ticks = ((usec * (get_tbclk()/1000)) + 500) / 1000;
+	else
+		ticks = ((usec / 10) * (get_tbclk() / 100000));
+
+	return ticks;
+}
+
+static inline unsigned long long tick_to_time(unsigned long long tick)
+{
+	unsigned long freq;
+
+	asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (freq));
+
+	tick *= CONFIG_SYS_HZ;
+	do_div(tick, freq);
+
+	return tick;
+}
+
+static inline unsigned long long us_to_tick(unsigned long long usec)
+{
+	unsigned long freq;
+
+	asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (freq));
+
+	usec = usec * freq  + 999999;
+	do_div(usec, 1000000);
+
+	return usec;
+}
+
+int timer_init(void)
+{
+	struct sctr_regs *sctr = (struct sctr_regs *)SCTR_BASE_ADDR;
+	unsigned long val, freq;
+
+	freq = CONFIG_SC_TIMER_CLK;
+	asm("mcr p15, 0, %0, c14, c0, 0" : : "r" (freq));
+
+	writel(freq, &sctr->cntfid0);
+
+	/* Enable system counter */
+	val = readl(&sctr->cntcr);
+	val &= ~(SC_CNTCR_FREQ0 | SC_CNTCR_FREQ1);
+	val |= SC_CNTCR_FREQ0 | SC_CNTCR_ENABLE | SC_CNTCR_HDBG;
+	writel(val, &sctr->cntcr);
+
+	gd->arch.tbl = 0;
+	gd->arch.tbu = 0;
+
+	return 0;
+}
+
+unsigned long long get_ticks(void)
+{
+	unsigned long long now;
+
+	asm("mrrc p15, 0, %Q0, %R0, c14" : "=r" (now));
+
+	gd->arch.tbl = (unsigned long)(now & 0xffffffff);
+	gd->arch.tbu = (unsigned long)(now >> 32);
+
+	return now;
+}
+
+ulong get_timer_masked(void)
+{
+	return tick_to_time(get_ticks());
+}
+
+ulong get_timer(ulong base)
+{
+	return get_timer_masked() - base;
+}
+
+void __udelay(unsigned long usec)
+{
+	unsigned long long tmp;
+	ulong tmo;
+
+	tmo = us_to_tick(usec);
+	tmp = get_ticks() + tmo;	/* get current timestamp */
+
+	while (get_ticks() < tmp)	/* loop till event */
+		 /*NOP*/;
+}
+
+/*
+ * 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)
+{
+	unsigned long freq;
+
+	asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (freq));
+
+	return freq;
+}
diff --git a/arch/arm/include/asm/imx-common/syscounter.h b/arch/arm/include/asm/imx-common/syscounter.h
new file mode 100644
index 0000000..bdbe26c
--- /dev/null
+++ b/arch/arm/include/asm/imx-common/syscounter.h
@@ -0,0 +1,29 @@ 
+/*
+ * Copyright (C) 2015 Freescale Semiconductor, Inc.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef _ASM_ARCH_SYSTEM_COUNTER_H
+#define _ASM_ARCH_SYSTEM_COUNTER_H
+
+/* System Counter */
+struct sctr_regs {
+	u32 cntcr;
+	u32 cntsr;
+	u32 cntcv1;
+	u32 cntcv2;
+	u32 resv1[4];
+	u32 cntfid0;
+	u32 cntfid1;
+	u32 cntfid2;
+	u32 resv2[1001];
+	u32 counterid[1];
+};
+
+#define SC_CNTCR_ENABLE		(1 << 0)
+#define SC_CNTCR_HDBG		(1 << 1)
+#define SC_CNTCR_FREQ0		(1 << 8)
+#define SC_CNTCR_FREQ1		(1 << 9)
+
+#endif