From 43417823fd8210edb7e714bea82ea9bd77089635 Mon Sep 17 00:00:00 2001 From: Tomi Valkeinen Date: Tue, 5 Mar 2013 16:34:05 +0200 Subject: [PATCH] OMAPDSS: DSS: add new clock calculation code Add new way to iterate over DSS clock divisors. dss_div_calc() provides a generic way to go over all the divisors, within given clock range. dss_div_calc() will call a callback function for each divider set, making the function reusable for all use cases. Signed-off-by: Tomi Valkeinen --- drivers/video/omap2/dss/dss.c | 39 +++++++++++++++++++++++++++++++++++ drivers/video/omap2/dss/dss.h | 3 +++ 2 files changed, 42 insertions(+) diff --git a/drivers/video/omap2/dss/dss.c b/drivers/video/omap2/dss/dss.c index 054c2a22b3f1..eba4127b61a6 100644 --- a/drivers/video/omap2/dss/dss.c +++ b/drivers/video/omap2/dss/dss.c @@ -473,6 +473,45 @@ int dss_calc_clock_rates(struct dss_clock_info *cinfo) return 0; } +bool dss_div_calc(unsigned long fck_min, dss_div_calc_func func, void *data) +{ + int fckd, fckd_start, fckd_stop; + unsigned long fck; + unsigned long fck_hw_max; + unsigned long fckd_hw_max; + unsigned long prate; + + if (dss.dpll4_m4_ck == NULL) { + /* + * TODO: dss1_fclk can be changed on OMAP2, but the available + * dividers are not continuous. We just use the pre-set rate for + * now. + */ + fck = clk_get_rate(dss.dss_clk); + fckd = 1; + return func(fckd, fck, data); + } + + fck_hw_max = dss_feat_get_param_max(FEAT_PARAM_DSS_FCK); + fckd_hw_max = dss.feat->fck_div_max; + + prate = dss_get_dpll4_rate() * dss.feat->dss_fck_multiplier; + + fck_min = fck_min ? fck_min : 1; + + fckd_start = min(prate / fck_min, fckd_hw_max); + fckd_stop = max(DIV_ROUND_UP(prate, fck_hw_max), 1ul); + + for (fckd = fckd_start; fckd >= fckd_stop; --fckd) { + fck = prate / fckd; + + if (func(fckd, fck, data)) + return true; + } + + return false; +} + int dss_set_clock_div(struct dss_clock_info *cinfo) { if (dss.dpll4_m4_ck) { diff --git a/drivers/video/omap2/dss/dss.h b/drivers/video/omap2/dss/dss.h index 0ff41dd8f3c5..4180302a7fb3 100644 --- a/drivers/video/omap2/dss/dss.h +++ b/drivers/video/omap2/dss/dss.h @@ -271,6 +271,9 @@ int dss_set_clock_div(struct dss_clock_info *cinfo); int dss_calc_clock_div(unsigned long req_pck, struct dss_clock_info *dss_cinfo, struct dispc_clock_info *dispc_cinfo); +typedef bool (*dss_div_calc_func)(int fckd, unsigned long fck, void *data); +bool dss_div_calc(unsigned long fck_min, dss_div_calc_func func, void *data); + /* SDI */ int sdi_init_platform_driver(void) __init; void sdi_uninit_platform_driver(void) __exit; -- 2.20.1