From: Dmitry Osipenko digetx@gmail.com
[ Upstream commit 6ac1571b4c60cb73a1f174b15ea93f7e38d74a88 ]
Commit 33a8eb8d40ee ("drm/tegra: dc: Implement runtime PM") introduced HW reset control. It causes a hang on Tegra20 if both display controllers are utilized (RGB panel and HDMI). The TRM suggests that each display controller has its own reset control, apparently it is not correct.
Fixes: 33a8eb8d40ee ("drm/tegra: dc: Implement runtime PM") Signed-off-by: Dmitry Osipenko digetx@gmail.com Reviewed-by: Erik Faye-Lund kusmabite@gmail.com Signed-off-by: Thierry Reding treding@nvidia.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com --- drivers/gpu/drm/tegra/dc.c | 30 +++++++++++++++++++++--------- 1 file changed, 21 insertions(+), 9 deletions(-)
diff --git a/drivers/gpu/drm/tegra/dc.c b/drivers/gpu/drm/tegra/dc.c index 4010d69cbd08..e93cbe7e8f5c 100644 --- a/drivers/gpu/drm/tegra/dc.c +++ b/drivers/gpu/drm/tegra/dc.c @@ -30,6 +30,7 @@ struct tegra_dc_soc_info { bool supports_block_linear; unsigned int pitch_align; bool has_powergate; + bool broken_reset; };
struct tegra_plane { @@ -1847,6 +1848,7 @@ static const struct tegra_dc_soc_info tegra20_dc_soc_info = { .supports_block_linear = false, .pitch_align = 8, .has_powergate = false, + .broken_reset = true, };
static const struct tegra_dc_soc_info tegra30_dc_soc_info = { @@ -1856,6 +1858,7 @@ static const struct tegra_dc_soc_info tegra30_dc_soc_info = { .supports_block_linear = false, .pitch_align = 8, .has_powergate = false, + .broken_reset = false, };
static const struct tegra_dc_soc_info tegra114_dc_soc_info = { @@ -1865,6 +1868,7 @@ static const struct tegra_dc_soc_info tegra114_dc_soc_info = { .supports_block_linear = false, .pitch_align = 64, .has_powergate = true, + .broken_reset = false, };
static const struct tegra_dc_soc_info tegra124_dc_soc_info = { @@ -1874,6 +1878,7 @@ static const struct tegra_dc_soc_info tegra124_dc_soc_info = { .supports_block_linear = true, .pitch_align = 64, .has_powergate = true, + .broken_reset = false, };
static const struct tegra_dc_soc_info tegra210_dc_soc_info = { @@ -1883,6 +1888,7 @@ static const struct tegra_dc_soc_info tegra210_dc_soc_info = { .supports_block_linear = true, .pitch_align = 64, .has_powergate = true, + .broken_reset = false, };
static const struct of_device_id tegra_dc_of_match[] = { @@ -1980,7 +1986,8 @@ static int tegra_dc_probe(struct platform_device *pdev) return PTR_ERR(dc->rst); }
- reset_control_assert(dc->rst); + if (!dc->soc->broken_reset) + reset_control_assert(dc->rst);
if (dc->soc->has_powergate) { if (dc->pipe == 0) @@ -2054,10 +2061,12 @@ static int tegra_dc_suspend(struct device *dev) struct tegra_dc *dc = dev_get_drvdata(dev); int err;
- err = reset_control_assert(dc->rst); - if (err < 0) { - dev_err(dev, "failed to assert reset: %d\n", err); - return err; + if (!dc->soc->broken_reset) { + err = reset_control_assert(dc->rst); + if (err < 0) { + dev_err(dev, "failed to assert reset: %d\n", err); + return err; + } }
if (dc->soc->has_powergate) @@ -2087,10 +2096,13 @@ static int tegra_dc_resume(struct device *dev) return err; }
- err = reset_control_deassert(dc->rst); - if (err < 0) { - dev_err(dev, "failed to deassert reset: %d\n", err); - return err; + if (!dc->soc->broken_reset) { + err = reset_control_deassert(dc->rst); + if (err < 0) { + dev_err(dev, + "failed to deassert reset: %d\n", err); + return err; + } } }