[U-Boot] [PATCH 3/6] ARM: tegra: clk_m is the architected timer source clock

Thierry Reding
2015-08-20T09:42:20Z

While clk_m and the oscillator run at the same frequencies on Tegra114
and Tegra124, clk_m is the proper source for the architected timer. On
more recent Tegra generations, Tegra210 and later, both the oscillator
and clk_m can run at different frequencies. clk_m will be divided down
from the oscillator.

Signed-off-by: Thierry Reding <treding@nvidia.com>
---
arch/arm/mach-tegra/tegra114/clock.c | 4 ++--
arch/arm/mach-tegra/tegra124/clock.c | 4 ++--
arch/arm/mach-tegra/tegra210/clock.c | 10 ++++------
3 files changed, 8 insertions(+), 10 deletions(-)

diff --git a/arch/arm/mach-tegra/tegra114/clock.c b/arch/arm/mach-tegra/tegra114/clock.c
index 5e805a7baf03..cec843b27df7 100644
--- a/arch/arm/mach-tegra/tegra114/clock.c
+++ b/arch/arm/mach-tegra/tegra114/clock.c
@@ -679,8 +679,8 @@ void arch_timer_init(void)
struct sysctr_ctlr *sysctr = (struct sysctr_ctlr *)NV_PA_TSC_BASE;
u32 freq, val;

- freq = clock_get_rate(CLOCK_ID_OSC);
- debug("%s: osc freq is %dHz [0x%08X]\n", __func__, freq, freq);
+ freq = clock_get_rate(CLOCK_ID_CLK_M);
+ debug("%s: clk_m freq is %dHz [0x%08X]\n", __func__, freq, freq);

/* ARM CNTFRQ */
asm("mcr p15, 0, %0, c14, c0, 0\n" : : "r" (freq));
diff --git a/arch/arm/mach-tegra/tegra124/clock.c b/arch/arm/mach-tegra/tegra124/clock.c
index 61e8ab7053fd..aa046e8950f7 100644
--- a/arch/arm/mach-tegra/tegra124/clock.c
+++ b/arch/arm/mach-tegra/tegra124/clock.c
@@ -859,8 +859,8 @@ void arch_timer_init(void)
struct sysctr_ctlr *sysctr = (struct sysctr_ctlr *)NV_PA_TSC_BASE;
u32 freq, val;

- freq = clock_get_rate(CLOCK_ID_OSC);
- debug("%s: osc freq is %dHz [0x%08X]\n", __func__, freq, freq);
+ freq = clock_get_rate(CLOCK_ID_CLK_M);
+ debug("%s: clk_m freq is %dHz [0x%08X]\n", __func__, freq, freq);

/* ARM CNTFRQ */
asm("mcr p15, 0, %0, c14, c0, 0\n" : : "r" (freq));
diff --git a/arch/arm/mach-tegra/tegra210/clock.c b/arch/arm/mach-tegra/tegra210/clock.c
index 146bb6453a19..6d75d371cb03 100644
--- a/arch/arm/mach-tegra/tegra210/clock.c
+++ b/arch/arm/mach-tegra/tegra210/clock.c
@@ -1014,13 +1014,11 @@ void arch_timer_init(void)
struct sysctr_ctlr *sysctr = (struct sysctr_ctlr *)NV_PA_TSC_BASE;
u32 freq, val;

- freq = clock_get_rate(CLOCK_ID_OSC);
- debug("%s: osc freq is %dHz [0x%08X]\n", __func__, freq, freq);
+ freq = clock_get_rate(CLOCK_ID_CLK_M);
+ debug("%s: clk_m freq is %dHz [0x%08X]\n", __func__, freq, freq);

- /* ARM CNTFRQ */
-#ifndef CONFIG_ARM64
- asm("mcr p15, 0, %0, c14, c0, 0\n" : : "r" (freq));
-#endif
+ if (current_el() == 3)
+ asm("msr cntfrq_el0, %0\n" : : "r" (freq));

/* Only Tegra114+ has the System Counter regs */
debug("%s: setting CNTFID0 to 0x%08X\n", __func__, freq);
--
2.4.5