Re: [PATCH AUTOSEL 5.11 26/52] clk: qcom: gdsc: Implement NO_RET_PERIPH flag
From: Stephen Boyd <sboyd@kernel.org>
Date: 2021-03-03 10:53:21
Also in:
linux-clk, lkml
Quoting Sasha Levin (2021-03-02 03:55:07)
From: AngeloGioacchino Del Regno <redacted> [ 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.
Is there a patch that's going to use this in stable trees? On its own this patch doesn't make sense to backport.
quoted hunk ↗ jump to hunk
Signed-off-by: AngeloGioacchino Del Regno <redacted> Link: https://lore.kernel.org/r/20210113183817.447866-8-angelogioacchino.delregno@somainline.org (local) 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;