From: Eric Yuen <[email protected]>

Depending on the prior state of the controller, the PLL reset may not be
pulsed. Clear the register bit and set it after a small delay to ensure
that the PLL is really reset.

Signed-off-by: Eric Yuen <[email protected]>
Signed-off-by: Thierry Reding <[email protected]>
---
 drivers/pci/host/pci-tegra.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/pci/host/pci-tegra.c b/drivers/pci/host/pci-tegra.c
index 8264bce77750..0ce43764dd36 100644
--- a/drivers/pci/host/pci-tegra.c
+++ b/drivers/pci/host/pci-tegra.c
@@ -849,6 +849,13 @@ static int tegra_pcie_enable_controller(struct tegra_pcie 
*pcie)
        value |= PADS_PLL_CTL_REFCLK_INTERNAL_CML | soc->tx_ref_sel;
        pads_writel(pcie, value, soc->pads_pll_ctl);
 
+       /* reset PLL */
+       value = pads_readl(pcie, soc->pads_pll_ctl);
+       value &= ~PADS_PLL_CTL_RST_B4SM;
+       pads_writel(pcie, value, soc->pads_pll_ctl);
+
+       usleep_range(20, 100);
+
        /* take PLL out of reset  */
        value = pads_readl(pcie, soc->pads_pll_ctl);
        value |= PADS_PLL_CTL_RST_B4SM;
-- 
2.0.4

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