From d6f987c8462ab97591fbd6ed6bea6df61d2919e5 Mon Sep 17 00:00:00 2001 From: Martin Blumenstingl Date: Sun, 24 Mar 2019 17:43:27 +0100 Subject: [PATCH 1/2] clk: meson: pll: fix rounding and setting a rate that matches precisely Make meson_clk_pll_is_better() consider a rate that precisely matches the requested rate to be better than any previous rate (which was smaller than the current). Prior to commit 8eed1db1adec6a ("clk: meson: pll: update driver for the g12a") meson_clk_get_pll_settings() returned early (before calling meson_clk_pll_is_better()) if the rate from the current iteration matches the requested rate precisely. After this commit meson_clk_pll_is_better() is called unconditionally. This requires meson_clk_pll_is_better() to work with the case where "now == rate". This fixes a hang during boot on Meson8b / Odroid-C1 for me. Fixes: 8eed1db1adec6a ("clk: meson: pll: update driver for the g12a") Signed-off-by: Martin Blumenstingl Reviewed-by: Jerome Brunet Signed-off-by: Neil Armstrong Link: https://lkml.kernel.org/r/20190324164327.22590-2-martin.blumenstingl@googlemail.com --- drivers/clk/meson/clk-pll.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/clk/meson/clk-pll.c b/drivers/clk/meson/clk-pll.c index 41e16dd7272a..7a14ac9b2fec 100644 --- a/drivers/clk/meson/clk-pll.c +++ b/drivers/clk/meson/clk-pll.c @@ -120,7 +120,7 @@ static bool meson_clk_pll_is_better(unsigned long rate, return true; } else { /* Round down */ - if (now < rate && best < now) + if (now <= rate && best < now) return true; } From 6620f45ff8519549a6877663f965c10002918dc2 Mon Sep 17 00:00:00 2001 From: Neil Armstrong Date: Wed, 27 Mar 2019 16:13:48 +0100 Subject: [PATCH 2/2] clk: meson: vid-pll-div: remove warning and return 0 on invalid config The vid_pll_div is a programmable fractional divider, but vendor gives a limited of known configuration value and it's corresponding fraction. Thus when at reset value (0) or unknown value, we cannot determine the result rate. The initial behaviour was to print a warning, but the warning triggers at each boot and when the clock tree is refreshed. This patch moves the print to debug and returns 0 instead of the parent rate. Fixes: 72dbb8c94d0d ("clk: meson: Add vid_pll divider driver") Signed-off-by: Neil Armstrong Reviewed-by: Jerome Brunet Link: https://lkml.kernel.org/r/20190327151348.27402-1-narmstrong@baylibre.com --- drivers/clk/meson/vid-pll-div.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/clk/meson/vid-pll-div.c b/drivers/clk/meson/vid-pll-div.c index 08bcc01c0923..daff235bc763 100644 --- a/drivers/clk/meson/vid-pll-div.c +++ b/drivers/clk/meson/vid-pll-div.c @@ -82,8 +82,8 @@ static unsigned long meson_vid_pll_div_recalc_rate(struct clk_hw *hw, div = _get_table_val(meson_parm_read(clk->map, &pll_div->val), meson_parm_read(clk->map, &pll_div->sel)); if (!div || !div->divider) { - pr_info("%s: Invalid config value for vid_pll_div\n", __func__); - return parent_rate; + pr_debug("%s: Invalid config value for vid_pll_div\n", __func__); + return 0; } return DIV_ROUND_UP_ULL(parent_rate * div->multiplier, div->divider);