[PATCH v2 4/7] clk: tegra: Enable hardware control of SATA PLL

Andrew Bresticker abrestic at chromium.org
Mon Jul 7 18:26:33 PDT 2014


On Wed, Jun 18, 2014 at 7:23 AM, Mikko Perttunen <mperttunen at nvidia.com> wrote:
> This makes the SATA PLL be controlled by hardware instead of software.
> This is required for working SATA support.
>
> Signed-off-by: Mikko Perttunen <mperttunen at nvidia.com>
> Acked-by: Stephen Warren <swarren at nvidia.com>

I know Peter sent a pull request including this patch already, but I
don't see it yet in Mike's tree, so perhaps it's possible to address
my comment below (or else I'll include it in the next spin of my XUSB
series.

> diff --git a/drivers/clk/tegra/clk-pll.c b/drivers/clk/tegra/clk-pll.c

> @@ -1361,6 +1364,11 @@ static int clk_plle_tegra114_enable(struct clk_hw *hw)
>         val |= XUSBIO_PLL_CFG0_SEQ_ENABLE;
>         pll_writel(val, XUSBIO_PLL_CFG0, pll);
>
> +       /* Enable hw control of SATA pll */
> +       val = pll_readl(SATA_PLL_CFG0, pll);
> +       val &= ~SATA_PLL_CFG0_PADPLL_RESET_SWCTL;
> +       pll_writel(val, SATA_PLL_CFG0, pll);
> +

Apparently the procedure for enabling the SATA PLL for XUSB (when the
SATA lane is used) is slightly different.  Specifically, it would be:

val = pll_readl(SATA_PLL_CFG0, pll);
val &= ~SATA_PLL_CFG0_PADPLL_RESET_SWCTL;
val |= SATA_PLL_CFG0_PADPLL_USE_LOCKDET;
val |= SATA_PLL_CFG0_SEQ_START_STATE;
pll_writel(val, SATA_PLL_CFG0, pll);

udelay(1);

val = pll_readl(SATA_PLL_CFG0, pll);
val |= SATA_PLL_CFG0_SEQ_ENABLE;
pll_writel(val, SATA_PLL_CFG0, pll);

Do you know if this sequence also works when the SATA lane is used for SATA?



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