Re: [PATCH v5 1/9] clk: mediatek: Disable tuner_en before change PLL rate

From: Matthias Brugger
Date: Thu Mar 07 2019 - 11:09:31 EST




On 05/03/2019 06:05, Weiyi Lu wrote:
> From: Owen Chen <owen.chen@xxxxxxxxxxxx>
>
> PLLs with tuner_en bit, such as APLL1, need to disable
> tuner_en before apply new frequency settings, or the new frequency
> settings (pcw) will not be applied.
> The tuner_en bit will be disabled during changing PLL rate
> and be restored after new settings applied.
>
> Fixes: e2f744a82d725 (clk: mediatek: Add MT2712 clock support)
> Cc: <stable@xxxxxxxxxxxxxxx>
> Signed-off-by: Owen Chen <owen.chen@xxxxxxxxxxxx>
> Signed-off-by: Weiyi Lu <weiyi.lu@xxxxxxxxxxxx>

Reviewed-by: Matthias Brugger <matthias.bgg@xxxxxxxxx>

> ---
> drivers/clk/mediatek/clk-pll.c | 48 ++++++++++++++++++++++++----------
> 1 file changed, 34 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/clk/mediatek/clk-pll.c b/drivers/clk/mediatek/clk-pll.c
> index f54e4015b0b1..18842d660317 100644
> --- a/drivers/clk/mediatek/clk-pll.c
> +++ b/drivers/clk/mediatek/clk-pll.c
> @@ -88,6 +88,32 @@ static unsigned long __mtk_pll_recalc_rate(struct mtk_clk_pll *pll, u32 fin,
> return ((unsigned long)vco + postdiv - 1) / postdiv;
> }
>
> +static void __mtk_pll_tuner_enable(struct mtk_clk_pll *pll)
> +{
> + u32 r;
> +
> + if (pll->tuner_en_addr) {
> + r = readl(pll->tuner_en_addr) | BIT(pll->data->tuner_en_bit);
> + writel(r, pll->tuner_en_addr);
> + } else if (pll->tuner_addr) {
> + r = readl(pll->tuner_addr) | AUDPLL_TUNER_EN;
> + writel(r, pll->tuner_addr);
> + }
> +}
> +
> +static void __mtk_pll_tuner_disable(struct mtk_clk_pll *pll)
> +{
> + u32 r;
> +
> + if (pll->tuner_en_addr) {
> + r = readl(pll->tuner_en_addr) & ~BIT(pll->data->tuner_en_bit);
> + writel(r, pll->tuner_en_addr);
> + } else if (pll->tuner_addr) {
> + r = readl(pll->tuner_addr) & ~AUDPLL_TUNER_EN;
> + writel(r, pll->tuner_addr);
> + }
> +}
> +
> static void mtk_pll_set_rate_regs(struct mtk_clk_pll *pll, u32 pcw,
> int postdiv)
> {
> @@ -96,6 +122,9 @@ static void mtk_pll_set_rate_regs(struct mtk_clk_pll *pll, u32 pcw,
>
> pll_en = readl(pll->base_addr + REG_CON0) & CON0_BASE_EN;
>
> + /* disable tuner */
> + __mtk_pll_tuner_disable(pll);
> +
> /* set postdiv */
> val = readl(pll->pd_addr);
> val &= ~(POSTDIV_MASK << pll->data->pd_shift);
> @@ -122,6 +151,9 @@ static void mtk_pll_set_rate_regs(struct mtk_clk_pll *pll, u32 pcw,
> if (pll->tuner_addr)
> writel(con1 + 1, pll->tuner_addr);
>
> + /* restore tuner_en */
> + __mtk_pll_tuner_enable(pll);
> +
> if (pll_en)
> udelay(20);
> }
> @@ -228,13 +260,7 @@ static int mtk_pll_prepare(struct clk_hw *hw)
> r |= pll->data->en_mask;
> writel(r, pll->base_addr + REG_CON0);
>
> - if (pll->tuner_en_addr) {
> - r = readl(pll->tuner_en_addr) | BIT(pll->data->tuner_en_bit);
> - writel(r, pll->tuner_en_addr);
> - } else if (pll->tuner_addr) {
> - r = readl(pll->tuner_addr) | AUDPLL_TUNER_EN;
> - writel(r, pll->tuner_addr);
> - }
> + __mtk_pll_tuner_enable(pll);
>
> udelay(20);
>
> @@ -258,13 +284,7 @@ static void mtk_pll_unprepare(struct clk_hw *hw)
> writel(r, pll->base_addr + REG_CON0);
> }
>
> - if (pll->tuner_en_addr) {
> - r = readl(pll->tuner_en_addr) & ~BIT(pll->data->tuner_en_bit);
> - writel(r, pll->tuner_en_addr);
> - } else if (pll->tuner_addr) {
> - r = readl(pll->tuner_addr) & ~AUDPLL_TUNER_EN;
> - writel(r, pll->tuner_addr);
> - }
> + __mtk_pll_tuner_disable(pll);
>
> r = readl(pll->base_addr + REG_CON0);
> r &= ~CON0_BASE_EN;
>