From: Tomi Valkeinen Date: Mon, 29 Aug 2011 12:56:04 +0000 (+0300) Subject: OMAP: DSS2: DISPC: Fix minimum PCD value X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=9eaaf2076dac213c034c69051dd7a625cd41f56e;p=linux-beck.git OMAP: DSS2: DISPC: Fix minimum PCD value The current driver had a hardcoded minimum value of 2 for pixel clock divisor (PCD). This doesn't seem to be right. OMAP4 TRM says that PCD can be 1 when not downscaling, and inverted pixel clock (IPC) is off. OMAP3 TRM says the same, but also in the register descriptions that PCD value 1 is invalid. OMAP2 TRM says PCD 2 is the minimum. OMAP2 is still untested, but for both OMAP3 and OMAP4 PCD of 1 seems to work fine. This patch adds a new DSS feature, FEAT_PARAM_DSS_PCD, which is used to find the minimum and maximum PCD. The minimum is set to 2 for OMAP2, and 1 for OMAP3/4. Signed-off-by: Tomi Valkeinen --- diff --git a/drivers/video/omap2/dss/dispc.c b/drivers/video/omap2/dss/dispc.c index b4a16cf9be1c..4e9f87fc33d8 100644 --- a/drivers/video/omap2/dss/dispc.c +++ b/drivers/video/omap2/dss/dispc.c @@ -2334,7 +2334,7 @@ static void dispc_mgr_set_lcd_divisor(enum omap_channel channel, u16 lck_div, u16 pck_div) { BUG_ON(lck_div < 1); - BUG_ON(pck_div < 2); + BUG_ON(pck_div < 1); dispc_write_reg(DISPC_DIVISORo(channel), FLD_VAL(lck_div, 23, 16) | FLD_VAL(pck_div, 7, 0)); @@ -2721,11 +2721,17 @@ void dispc_mgr_set_pol_freq(enum omap_channel channel, void dispc_find_clk_divs(bool is_tft, unsigned long req_pck, unsigned long fck, struct dispc_clock_info *cinfo) { - u16 pcd_min = is_tft ? 2 : 3; + u16 pcd_min, pcd_max; unsigned long best_pck; u16 best_ld, cur_ld; u16 best_pd, cur_pd; + pcd_min = dss_feat_get_param_min(FEAT_PARAM_DSS_PCD); + pcd_max = dss_feat_get_param_max(FEAT_PARAM_DSS_PCD); + + if (!is_tft) + pcd_min = 3; + best_pck = 0; best_ld = 0; best_pd = 0; @@ -2733,7 +2739,7 @@ void dispc_find_clk_divs(bool is_tft, unsigned long req_pck, unsigned long fck, for (cur_ld = 1; cur_ld <= 255; ++cur_ld) { unsigned long lck = fck / cur_ld; - for (cur_pd = pcd_min; cur_pd <= 255; ++cur_pd) { + for (cur_pd = pcd_min; cur_pd <= pcd_max; ++cur_pd) { unsigned long pck = lck / cur_pd; long old_delta = abs(best_pck - req_pck); long new_delta = abs(pck - req_pck); @@ -2768,7 +2774,7 @@ int dispc_calc_clock_rates(unsigned long dispc_fclk_rate, { if (cinfo->lck_div > 255 || cinfo->lck_div == 0) return -EINVAL; - if (cinfo->pck_div < 2 || cinfo->pck_div > 255) + if (cinfo->pck_div < 1 || cinfo->pck_div > 255) return -EINVAL; cinfo->lck = dispc_fclk_rate / cinfo->lck_div; diff --git a/drivers/video/omap2/dss/dss_features.c b/drivers/video/omap2/dss/dss_features.c index 86706123a247..076f399a9153 100644 --- a/drivers/video/omap2/dss/dss_features.c +++ b/drivers/video/omap2/dss/dss_features.c @@ -281,6 +281,7 @@ static const char * const omap4_dss_clk_source_names[] = { static const struct dss_param_range omap2_dss_param_range[] = { [FEAT_PARAM_DSS_FCK] = { 0, 173000000 }, + [FEAT_PARAM_DSS_PCD] = { 2, 255 }, [FEAT_PARAM_DSIPLL_REGN] = { 0, 0 }, [FEAT_PARAM_DSIPLL_REGM] = { 0, 0 }, [FEAT_PARAM_DSIPLL_REGM_DISPC] = { 0, 0 }, @@ -291,6 +292,7 @@ static const struct dss_param_range omap2_dss_param_range[] = { static const struct dss_param_range omap3_dss_param_range[] = { [FEAT_PARAM_DSS_FCK] = { 0, 173000000 }, + [FEAT_PARAM_DSS_PCD] = { 1, 255 }, [FEAT_PARAM_DSIPLL_REGN] = { 0, (1 << 7) - 1 }, [FEAT_PARAM_DSIPLL_REGM] = { 0, (1 << 11) - 1 }, [FEAT_PARAM_DSIPLL_REGM_DISPC] = { 0, (1 << 4) - 1 }, @@ -301,6 +303,7 @@ static const struct dss_param_range omap3_dss_param_range[] = { static const struct dss_param_range omap4_dss_param_range[] = { [FEAT_PARAM_DSS_FCK] = { 0, 186000000 }, + [FEAT_PARAM_DSS_PCD] = { 1, 255 }, [FEAT_PARAM_DSIPLL_REGN] = { 0, (1 << 8) - 1 }, [FEAT_PARAM_DSIPLL_REGM] = { 0, (1 << 12) - 1 }, [FEAT_PARAM_DSIPLL_REGM_DISPC] = { 0, (1 << 5) - 1 }, diff --git a/drivers/video/omap2/dss/dss_features.h b/drivers/video/omap2/dss/dss_features.h index c4321908f322..f73585e09d27 100644 --- a/drivers/video/omap2/dss/dss_features.h +++ b/drivers/video/omap2/dss/dss_features.h @@ -77,6 +77,7 @@ enum dss_feat_reg_field { enum dss_range_param { FEAT_PARAM_DSS_FCK, + FEAT_PARAM_DSS_PCD, FEAT_PARAM_DSIPLL_REGN, FEAT_PARAM_DSIPLL_REGM, FEAT_PARAM_DSIPLL_REGM_DISPC,