diff options
| author | Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> | 2025-05-20 13:13:26 +0200 |
|---|---|---|
| committer | Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> | 2025-06-09 08:33:41 +0300 |
| commit | 8a48e35becb214743214f5504e726c3ec131cd6d (patch) | |
| tree | f390a4f13a031cc09c662c3b9c9a74a03960d26c | |
| parent | 146e87f3e11de0dfa091ff87e34b4bc6eec761a4 (diff) | |
drm/msm/dsi/dsi_phy_10nm: Fix missing initial VCO rate
Driver unconditionally saves current state on first init in
dsi_pll_10nm_init(), but does not save the VCO rate, only some of the
divider registers. The state is then restored during probe/enable via
msm_dsi_phy_enable() -> msm_dsi_phy_pll_restore_state() ->
dsi_10nm_pll_restore_state().
Restoring calls dsi_pll_10nm_vco_set_rate() with
pll_10nm->vco_current_rate=0, which basically overwrites existing rate of
VCO and messes with clock hierarchy, by setting frequency to 0 to clock
tree. This makes anyway little sense - VCO rate was not saved, so
should not be restored.
If PLL was not configured configure it to minimum rate to avoid glitches
and configuring entire in clock hierarchy to 0 Hz.
Suggested-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Link: https://lore.kernel.org/r/sz4kbwy5nwsebgf64ia7uq4ee7wbsa5uy3xmlqwcstsbntzcov@ew3dcyjdzmi2/
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Fixes: a4ccc37693a2 ("drm/msm/dsi_pll_10nm: restore VCO rate during
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Patchwork: https://patchwork.freedesktop.org/patch/654796/
Link: https://lore.kernel.org/r/20250520111325.92352-2-krzysztof.kozlowski@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
| -rw-r--r-- | drivers/gpu/drm/msm/dsi/phy/dsi_phy_10nm.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/gpu/drm/msm/dsi/phy/dsi_phy_10nm.c b/drivers/gpu/drm/msm/dsi/phy/dsi_phy_10nm.c index 9812b4d69197..af2e30f3f842 100644 --- a/drivers/gpu/drm/msm/dsi/phy/dsi_phy_10nm.c +++ b/drivers/gpu/drm/msm/dsi/phy/dsi_phy_10nm.c @@ -704,6 +704,13 @@ static int dsi_pll_10nm_init(struct msm_dsi_phy *phy) /* TODO: Remove this when we have proper display handover support */ msm_dsi_phy_pll_save_state(phy); + /* + * Store also proper vco_current_rate, because its value will be used in + * dsi_10nm_pll_restore_state(). + */ + if (!dsi_pll_10nm_vco_recalc_rate(&pll_10nm->clk_hw, VCO_REF_CLK_RATE)) + pll_10nm->vco_current_rate = pll_10nm->phy->cfg->min_pll_rate; + return 0; } |