On 12/03/2015 06:48 PM, Tony Lindgren wrote:
* Tero Kristo <[email protected]> [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.
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