On 12/03/2015 06:48 PM, Tony Lindgren wrote:
* Tero Kristo <t-kri...@ti.com> [151130 06:44]:
+       /*
+        * Errata i810 - DPLL controller can get stuck while transitioning
+        * to a power saving state. Software must ensure the DPLL can not
+        * transition to a low power state while changing M/N values.
+        * Easiest way to accomplish this is to prevent DPLL autoidle
+        * before doing the M/N re-program.
+        */
+       errata_i810 = ti_clk_get_features()->flags & TI_CLK_ERRATA_I810;
+
+       if (errata_i810) {
+               ai = omap3_dpll_autoidle_read(clk);
+               if (ai) {
+                       omap3_dpll_deny_idle(clk);
+
+                       /* OCP barrier */
+                       omap3_dpll_autoidle_read(clk);
+               }
+       }

Should we just do this unconditionally? It seems like disabling the
autoidle always before reprogramming is a good idea.

Well, that is a few extra register accesses, but given the DPLL re-programming is a slow operation it probably does not matter. Let me spin a new version of this patch, it will avoid the need for the errata flag also.

-Tero

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