On 05/02/2014 09:32 AM, George Cherian wrote:
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 <george.cher...@ti.com>

Acked-by: Tero Kristo <t-kri...@ti.com>

---
  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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