Re: [PATCH AUTOSEL 5.10 22/47] clk: qcom: gdsc: Implement NO_RET_PERIPH flag

Stephen Boyd
2021-03-03T10:53:46Z

Quoting Sasha Levin (2021-03-02 03:56:21)
> From: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
>
> [ Upstream commit 785c02eb35009a4be6dbc68f4f7d916e90b7177d ]
>
> In some rare occasions, we want to only set the RETAIN_MEM bit, but
> not the RETAIN_PERIPH one: this is seen on at least SDM630/636/660's
> GPU-GX GDSC, where unsetting and setting back the RETAIN_PERIPH bit
> will generate chaos and panics during GPU suspend time (mainly, the
> chaos is unaligned access).
>
> For this reason, introduce a new NO_RET_PERIPH flag to the GDSC
> driver to address this corner case.
>

Same comment as on 5.11

> Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
> Link: https://lore.kernel.org/r/20210113183817.447866-8-angelogioacchino.delregno@somainline.org
> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
> Signed-off-by: Sasha Levin <sashal@kernel.org>
> ---
> drivers/clk/qcom/gdsc.c | 10 ++++++++--
> drivers/clk/qcom/gdsc.h | 3 ++-
> 2 files changed, 10 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/clk/qcom/gdsc.c b/drivers/clk/qcom/gdsc.c
> index af26e0695b86..51ed640e527b 100644
> --- a/drivers/clk/qcom/gdsc.c
> +++ b/drivers/clk/qcom/gdsc.c
> @@ -183,7 +183,10 @@ static inline int gdsc_assert_reset(struct gdsc *sc)
> static inline void gdsc_force_mem_on(struct gdsc *sc)
> {
> int i;
> - u32 mask = RETAIN_MEM | RETAIN_PERIPH;
> + u32 mask = RETAIN_MEM;
> +
> + if (!(sc->flags & NO_RET_PERIPH))
> + mask |= RETAIN_PERIPH;
>
> for (i = 0; i < sc->cxc_count; i++)
> regmap_update_bits(sc->regmap, sc->cxcs[i], mask, mask);
> @@ -192,7 +195,10 @@ static inline void gdsc_force_mem_on(struct gdsc *sc)
> static inline void gdsc_clear_mem_on(struct gdsc *sc)
> {
> int i;
> - u32 mask = RETAIN_MEM | RETAIN_PERIPH;
> + u32 mask = RETAIN_MEM;
> +
> + if (!(sc->flags & NO_RET_PERIPH))
> + mask |= RETAIN_PERIPH;
>
> for (i = 0; i < sc->cxc_count; i++)
> regmap_update_bits(sc->regmap, sc->cxcs[i], mask, 0);
> diff --git a/drivers/clk/qcom/gdsc.h b/drivers/clk/qcom/gdsc.h
> index bd537438c793..5bb396b344d1 100644
> --- a/drivers/clk/qcom/gdsc.h
> +++ b/drivers/clk/qcom/gdsc.h
> @@ -42,7 +42,7 @@ struct gdsc {
> #define PWRSTS_ON BIT(2)
> #define PWRSTS_OFF_ON (PWRSTS_OFF | PWRSTS_ON)
> #define PWRSTS_RET_ON (PWRSTS_RET | PWRSTS_ON)
> - const u8 flags;
> + const u16 flags;
> #define VOTABLE BIT(0)
> #define CLAMP_IO BIT(1)
> #define HW_CTRL BIT(2)
> @@ -51,6 +51,7 @@ struct gdsc {
> #define POLL_CFG_GDSCR BIT(5)
> #define ALWAYS_ON BIT(6)
> #define RETAIN_FF_ENABLE BIT(7)
> +#define NO_RET_PERIPH BIT(8)
> struct reset_controller_dev *rcdev;
> unsigned int *resets;
> unsigned int reset_count;
> --
> 2.30.1
>