[PATCH v2 5/6] ARM: AM43xx: clk: Change the cpts ref clock source to dpll_core_m5 clk
From: George Cherian <hidden>
Date: 2014-05-02 06:35:45
Also in:
linux-arm-kernel, linux-devicetree, linux-omap, lkml
Subsystem:
common clk framework, the rest, ti clock driver · Maintainers:
Michael Turquette, Stephen Boyd, Linus Torvalds, Tero Kristo
cpsw_cpts_rft_clk has got the choice of 3 clocksources -dpll_core_m4_ck -dpll_core_m5_ck -dpll_disp_m2_ck By default dpll_core_m4_ck is selected, witn this as clock source the CPTS doesnot work properly. It gives clockcheck errors while running PTP. clockcheck: clock jumped backward or running slower than expected! By selecting dpll_core_m5_ck as the clocksource fixes this issue. In AM335x dpll_core_m5_ck is the default clocksource. Signed-off-by: George Cherian <redacted> --- drivers/clk/ti/clk-43xx.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
diff --git a/drivers/clk/ti/clk-43xx.c b/drivers/clk/ti/clk-43xx.c
index 67c8de5..b4877e0 100644
--- a/drivers/clk/ti/clk-43xx.c
+++ b/drivers/clk/ti/clk-43xx.c@@ -110,9 +110,25 @@ static struct ti_dt_clk am43xx_clks[] = { int __init am43xx_dt_clk_init(void) { + struct clk *clk1, *clk2; + ti_dt_clocks_register(am43xx_clks); omap2_clk_disable_autoidle_all(); + /* + * cpsw_cpts_rft_clk has got the choice of 3 clocksources + * dpll_core_m4_ck, dpll_core_m5_ck and dpll_disp_m2_ck. + * By default dpll_core_m4_ck is selected, witn this as clock + * source the CPTS doesnot work properly. It gives clockcheck errors + * while running PTP. + * clockcheck: clock jumped backward or running slower than expected! + * By selecting dpll_core_m5_ck as the clocksource fixes this issue. + * In AM335x dpll_core_m5_ck is the default clocksource. + */ + clk1 = clk_get_sys(NULL, "cpsw_cpts_rft_clk"); + clk2 = clk_get_sys(NULL, "dpll_core_m5_ck"); + clk_set_parent(clk1, clk2); + return 0; }
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1.8.3.1