[PATCH v3 1/4] clk: qcom: gdsc: Add support to enable retention of GSDCR

Taniya Das
2020-06-10T17:18:39Z

Add support for the RETAIN_FF_ENABLE feature which enables the
usage of retention registers. These registers maintain their
state after disabling and re-enabling a GDSC.

Signed-off-by: Taniya Das <tdas@codeaurora.org>
---
drivers/clk/qcom/gdsc.c | 12 ++++++++++++
drivers/clk/qcom/gdsc.h | 1 +
2 files changed, 13 insertions(+)

diff --git a/drivers/clk/qcom/gdsc.c b/drivers/clk/qcom/gdsc.c
index 04944f1..2502430 100644
--- a/drivers/clk/qcom/gdsc.c
+++ b/drivers/clk/qcom/gdsc.c
@@ -29,6 +29,7 @@
/* CFG_GDSCR */
#define GDSC_POWER_UP_COMPLETE BIT(16)
#define GDSC_POWER_DOWN_COMPLETE BIT(15)
+#define GDSC_RETAIN_FF_ENABLE BIT(11)
#define CFG_GDSCR_OFFSET 0x4

/* Wait 2^n CXO cycles between all states. Here, n=2 (4 cycles). */
@@ -216,6 +217,14 @@ static inline void gdsc_assert_reset_aon(struct gdsc *sc)
regmap_update_bits(sc->regmap, sc->clamp_io_ctrl,
GMEM_RESET_MASK, 0);
}
+
+static void gdsc_retain_ff_on(struct gdsc *sc)
+{
+ u32 mask = GDSC_RETAIN_FF_ENABLE;
+
+ regmap_update_bits(sc->regmap, sc->gdscr, mask, mask);
+}
+
static int gdsc_enable(struct generic_pm_domain *domain)
{
struct gdsc *sc = domain_to_gdsc(domain);
@@ -268,6 +277,9 @@ static int gdsc_enable(struct generic_pm_domain *domain)
udelay(1);
}

+ if (sc->flags & RETAIN_FF_ENABLE)
+ gdsc_retain_ff_on(sc);
+
return 0;
}

diff --git a/drivers/clk/qcom/gdsc.h b/drivers/clk/qcom/gdsc.h
index c36fc26..a5076fe 100644
--- a/drivers/clk/qcom/gdsc.h
+++ b/drivers/clk/qcom/gdsc.h
@@ -50,6 +50,7 @@ struct gdsc {
#define AON_RESET BIT(4)
#define POLL_CFG_GDSCR BIT(5)
#define ALWAYS_ON BIT(6)
+#define RETAIN_FF_ENABLE BIT(7)
struct reset_controller_dev *rcdev;
unsigned int *resets;
unsigned int reset_count;