[PATCH 08/14] ARM: i.MX: implement pllv2 set/round_rate support
Sascha Hauer
s.hauer at pengutronix.de
Wed May 7 01:04:38 PDT 2014
Code straight from the kernel.
Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
---
arch/arm/mach-imx/clk-pllv2.c | 66 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 66 insertions(+)
diff --git a/arch/arm/mach-imx/clk-pllv2.c b/arch/arm/mach-imx/clk-pllv2.c
index 7e087c1..a2b016f 100644
--- a/arch/arm/mach-imx/clk-pllv2.c
+++ b/arch/arm/mach-imx/clk-pllv2.c
@@ -136,8 +136,74 @@ static unsigned long clk_pllv2_recalc_rate(struct clk *clk,
return __clk_pllv2_recalc_rate(parent_rate, dp_ctl, dp_op, dp_mfd, dp_mfn);
}
+static int __clk_pllv2_set_rate(unsigned long rate, unsigned long parent_rate,
+ u32 *dp_op, u32 *dp_mfd, u32 *dp_mfn)
+{
+ u32 reg;
+ long mfi, pdf, mfn, mfd = 999999;
+ u64 temp64;
+ unsigned long quad_parent_rate;
+
+ quad_parent_rate = 4 * parent_rate;
+ pdf = mfi = -1;
+ while (++pdf < 16 && mfi < 5)
+ mfi = rate * (pdf+1) / quad_parent_rate;
+ if (mfi > 15)
+ return -EINVAL;
+ pdf--;
+
+ temp64 = rate * (pdf + 1) - quad_parent_rate * mfi;
+ do_div(temp64, quad_parent_rate / 1000000);
+ mfn = (long)temp64;
+
+ reg = mfi << 4 | pdf;
+
+ *dp_op = reg;
+ *dp_mfd = mfd;
+ *dp_mfn = mfn;
+
+ return 0;
+}
+
+static int clk_pllv2_set_rate(struct clk *clk, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct clk_pllv2 *pll = container_of(clk, struct clk_pllv2, clk);
+ void __iomem *pllbase;
+ u32 dp_ctl, dp_op, dp_mfd, dp_mfn;
+ int ret;
+
+ pllbase = pll->reg;
+
+ ret = __clk_pllv2_set_rate(rate, parent_rate, &dp_op, &dp_mfd, &dp_mfn);
+ if (ret)
+ return ret;
+
+ dp_ctl = __raw_readl(pllbase + MXC_PLL_DP_CTL);
+ /* use dpdck0_2 */
+ __raw_writel(dp_ctl | 0x1000L, pllbase + MXC_PLL_DP_CTL);
+
+ __raw_writel(dp_op, pllbase + MXC_PLL_DP_OP);
+ __raw_writel(dp_mfd, pllbase + MXC_PLL_DP_MFD);
+ __raw_writel(dp_mfn, pllbase + MXC_PLL_DP_MFN);
+
+ return 0;
+}
+
+static long clk_pllv2_round_rate(struct clk *clk, unsigned long rate,
+ unsigned long *prate)
+{
+ u32 dp_op, dp_mfd, dp_mfn;
+
+ __clk_pllv2_set_rate(rate, *prate, &dp_op, &dp_mfd, &dp_mfn);
+ return __clk_pllv2_recalc_rate(*prate, MXC_PLL_DP_CTL_DPDCK0_2_EN,
+ dp_op, dp_mfd, dp_mfn);
+}
+
struct clk_ops clk_pllv2_ops = {
.recalc_rate = clk_pllv2_recalc_rate,
+ .round_rate = clk_pllv2_round_rate,
+ .set_rate = clk_pllv2_set_rate,
};
struct clk *imx_clk_pllv2(const char *name, const char *parent,
--
2.0.0.rc0
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