[PATCH] ARM i.MX27: Fix low reference clock path

Sascha Hauer s.hauer at pengutronix.de
Wed Oct 31 03:28:53 EDT 2012


The i.MX27 clock tree can either be driven from a 26MHz oscillator
or from a 32768Hz oscillator. The latter was not properly implemented,
the mux between these two pathes was missing. Add this mux and while
at it rename the 'prem' (premultiplier) clk to 'fpm' (Frequency
Pre-Multiplier) to better match the datasheet.

Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
---
 arch/arm/mach-imx/clk-imx27.c |   17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/arch/arm/mach-imx/clk-imx27.c b/arch/arm/mach-imx/clk-imx27.c
index 3b6b640..f8d9129 100644
--- a/arch/arm/mach-imx/clk-imx27.c
+++ b/arch/arm/mach-imx/clk-imx27.c
@@ -51,8 +51,10 @@
 
 static const char *vpu_sel_clks[] = { "spll", "mpll_main2", };
 static const char *cpu_sel_clks[] = { "mpll_main2", "mpll", };
+static const char *mpll_sel_clks[] = { "fpm", "mpll_osc_sel", };
+static const char *mpll_osc_sel_clks[] = { "ckih", "ckih_div1p5", };
 static const char *clko_sel_clks[] = {
-	"ckil", "prem", "ckih", "ckih",
+	"ckil", "fpm", "ckih", "ckih",
 	"ckih", "mpll", "spll", "cpu_div",
 	"ahb", "ipg", "per1_div", "per2_div",
 	"per3_div", "per4_div", "ssi1_div", "ssi2_div",
@@ -79,7 +81,8 @@ enum mx27_clks {
 	vpu_ahb_gate, fec_ahb_gate, emma_ahb_gate, emi_ahb_gate, dma_ahb_gate,
 	csi_ahb_gate, brom_ahb_gate, ata_ahb_gate, wdog_ipg_gate, usb_ipg_gate,
 	uart6_ipg_gate, uart5_ipg_gate, uart4_ipg_gate, uart3_ipg_gate,
-	uart2_ipg_gate, uart1_ipg_gate, clk_max
+	uart2_ipg_gate, uart1_ipg_gate, ckih_div1p5, fpm, mpll_osc_sel,
+	mpll_sel, clk_max
 };
 
 static struct clk *clk[clk_max];
@@ -91,7 +94,15 @@ int __init mx27_clocks_init(unsigned long fref)
 	clk[dummy] = imx_clk_fixed("dummy", 0);
 	clk[ckih] = imx_clk_fixed("ckih", fref);
 	clk[ckil] = imx_clk_fixed("ckil", 32768);
-	clk[mpll] = imx_clk_pllv1("mpll", "ckih", CCM_MPCTL0);
+	clk[fpm] = imx_clk_fixed_factor("fpm", "ckil", 1024, 1);
+	clk[ckih_div1p5] = imx_clk_fixed_factor("ckih_div1p5", "ckih", 2, 3);
+
+	clk[mpll_osc_sel] = imx_clk_mux("mpll_osc_sel", CCM_CSCR, 4, 1,
+			mpll_osc_sel_clks,
+			ARRAY_SIZE(mpll_osc_sel_clks));
+	clk[mpll_sel] = imx_clk_mux("mpll_sel", CCM_CSCR, 16, 1, mpll_sel_clks,
+			ARRAY_SIZE(mpll_sel_clks));
+	clk[mpll] = imx_clk_pllv1("mpll", "mpll_sel", CCM_MPCTL0);
 	clk[spll] = imx_clk_pllv1("spll", "ckih", CCM_SPCTL0);
 	clk[mpll_main2] = imx_clk_fixed_factor("mpll_main2", "mpll", 2, 3);
 
-- 
1.7.10.4




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