From: Dmitry Osipenko digetx@gmail.com
[ Upstream commit a7196048cd5168096c2c4f44a3939d7a6dcd06b9 ]
The PLLU (USB) consists of the PLL configuration itself and configuration of the PLLU outputs. The PLLU programming is inconsistent on T30 vs T114, where T114 immediately bails out if PLLU is enabled and T30 re-enables a potentially already enabled PLL (left after bootloader) and then fully reprograms it, which could be unsafe to do. The correct way should be to skip enabling of the PLL if it's already enabled and then apply configuration to the outputs. This patch doesn't fix any known problems, it's a minor improvement.
Acked-by: Thierry Reding treding@nvidia.com Signed-off-by: Dmitry Osipenko digetx@gmail.com Signed-off-by: Thierry Reding treding@nvidia.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/clk/tegra/clk-pll.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/drivers/clk/tegra/clk-pll.c b/drivers/clk/tegra/clk-pll.c index 0193cebe8c5a..823a567f2adc 100644 --- a/drivers/clk/tegra/clk-pll.c +++ b/drivers/clk/tegra/clk-pll.c @@ -1131,7 +1131,8 @@ static int clk_pllu_enable(struct clk_hw *hw) if (pll->lock) spin_lock_irqsave(pll->lock, flags);
- _clk_pll_enable(hw); + if (!clk_pll_is_enabled(hw)) + _clk_pll_enable(hw);
ret = clk_pll_wait_for_lock(pll); if (ret < 0) @@ -1748,15 +1749,13 @@ static int clk_pllu_tegra114_enable(struct clk_hw *hw) return -EINVAL; }
- if (clk_pll_is_enabled(hw)) - return 0; - input_rate = clk_hw_get_rate(__clk_get_hw(osc));
if (pll->lock) spin_lock_irqsave(pll->lock, flags);
- _clk_pll_enable(hw); + if (!clk_pll_is_enabled(hw)) + _clk_pll_enable(hw);
ret = clk_pll_wait_for_lock(pll); if (ret < 0)