[U-Boot] [PATCH v3 05/15] tegra: clock: Support enabling external clocks
Simon Glass
sjg at chromium.org
Fri Jun 5 22:39:36 CEST 2015
Add a simple function to enable external clocks.
Signed-off-by: Simon Glass <sjg at chromium.org>
---
Changes in v3: None
Changes in v2: None
arch/arm/include/asm/arch-tegra/clock.h | 8 ++++++++
arch/arm/mach-tegra/clock.c | 17 +++++++++++++++++
2 files changed, 25 insertions(+)
diff --git a/arch/arm/include/asm/arch-tegra/clock.h b/arch/arm/include/asm/arch-tegra/clock.h
index 04011ae..f9dd3c8 100644
--- a/arch/arm/include/asm/arch-tegra/clock.h
+++ b/arch/arm/include/asm/arch-tegra/clock.h
@@ -336,4 +336,12 @@ void arch_timer_init(void);
void tegra30_set_up_pllp(void);
+/**
+ * Enable output clock for external peripherals
+ *
+ * @param clk_id Clock ID to output (1, 2 or 3)
+ * @return 0 if OK. -ve on error
+ */
+int clock_external_output(int clk_id);
+
#endif /* _TEGRA_CLOCK_H_ */
diff --git a/arch/arm/mach-tegra/clock.c b/arch/arm/mach-tegra/clock.c
index cdd5438..5908260 100644
--- a/arch/arm/mach-tegra/clock.c
+++ b/arch/arm/mach-tegra/clock.c
@@ -17,11 +17,13 @@
/* Tegra SoC common clock control functions */
#include <common.h>
+#include <errno.h>
#include <asm/io.h>
#include <asm/arch/clock.h>
#include <asm/arch/tegra.h>
#include <asm/arch-tegra/ap.h>
#include <asm/arch-tegra/clk_rst.h>
+#include <asm/arch-tegra/pmc.h>
#include <asm/arch-tegra/timer.h>
#include <div64.h>
#include <fdtdec.h>
@@ -702,3 +704,18 @@ void tegra30_set_up_pllp(void)
set_avp_clock_source(SCLK_SOURCE_PLLP_OUT4);
}
+
+int clock_external_output(int clk_id)
+{
+ struct pmc_ctlr *pmc = (struct pmc_ctlr *)NV_PA_PMC_BASE;
+
+ if (clk_id >= 1 && clk_id <= 3) {
+ setbits_le32(&pmc->pmc_clk_out_cntrl,
+ 1 << (2 + (clk_id - 1) * 8));
+ } else {
+ printf("%s: Unknown output clock id %d\n", __func__, clk_id);
+ return -EINVAL;
+ }
+
+ return 0;
+}
--
2.2.0.rc0.207.ga3a616c
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