[U-Boot] [PATCH 3/4] mx25: Add function to set PER clocks

Benoît Thébaudeau
2017-05-03T09:59:05Z

Introduce the imx_set_perclk() function to make it possible to set the
PER clocks.

Signed-off-by: Benoît Thébaudeau <benoit@wsystem.com>
---
arch/arm/cpu/arm926ejs/mx25/generic.c | 19 +++++++++++++++++++
arch/arm/include/asm/arch-mx25/clock.h | 1 +
2 files changed, 20 insertions(+)

diff --git a/arch/arm/cpu/arm926ejs/mx25/generic.c b/arch/arm/cpu/arm926ejs/mx25/generic.c
index f02cffb..5d9bc6c 100644
--- a/arch/arm/cpu/arm926ejs/mx25/generic.c
+++ b/arch/arm/cpu/arm926ejs/mx25/generic.c
@@ -113,6 +113,25 @@ static ulong imx_get_perclk(int clk)
return fref / div;
}

+int imx_set_perclk(enum mxc_clock clk, bool from_upll, unsigned int freq)
+{
+ struct ccm_regs *ccm = (struct ccm_regs *)IMX_CCM_BASE;
+ ulong fref = from_upll ? imx_get_upllclk() : imx_get_ahbclk();
+ ulong div = (fref + freq - 1) / freq;
+
+ if (clk > MXC_UART_CLK || !div || --div > CCM_PERCLK_MASK)
+ return -EINVAL;
+
+ clrsetbits_le32(&ccm->pcdr[CCM_PERCLK_REG(clk)],
+ CCM_PERCLK_MASK << CCM_PERCLK_SHIFT(clk),
+ div << CCM_PERCLK_SHIFT(clk));
+ if (from_upll)
+ setbits_le32(&ccm->mcr, 1 << clk);
+ else
+ clrbits_le32(&ccm->mcr, 1 << clk);
+ return 0;
+}
+
unsigned int mxc_get_clock(enum mxc_clock clk)
{
if (clk >= MXC_CLK_NUM)
diff --git a/arch/arm/include/asm/arch-mx25/clock.h b/arch/arm/include/asm/arch-mx25/clock.h
index 9fdaa9d..7753caf 100644
--- a/arch/arm/include/asm/arch-mx25/clock.h
+++ b/arch/arm/include/asm/arch-mx25/clock.h
@@ -51,6 +51,7 @@ enum mxc_clock {
MXC_CLK_NUM
};

+int imx_set_perclk(enum mxc_clock clk, bool from_upll, unsigned int freq);
unsigned int mxc_get_clock(enum mxc_clock clk);

#define imx_get_uartclk() mxc_get_clock(MXC_UART_CLK)
--
2.7.4