[PATCH v6 12/18] clk: qcom: clk-krait: add apq/ipq8064 errata workaround

Ansuel Smith
2022-03-21T23:45:35Z

Add apq/ipq8064 errata workaround where the sec_src clock gating needs to
be disabled during switching. To enable this set disable_sec_src_gating
in the mux struct.

Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
---
drivers/clk/qcom/clk-krait.c | 16 ++++++++++++++++
drivers/clk/qcom/clk-krait.h | 1 +
drivers/clk/qcom/krait-cc.c | 1 +
3 files changed, 18 insertions(+)

diff --git a/drivers/clk/qcom/clk-krait.c b/drivers/clk/qcom/clk-krait.c
index b6b7650dbf15..7ba5dbc72bce 100644
--- a/drivers/clk/qcom/clk-krait.c
+++ b/drivers/clk/qcom/clk-krait.c
@@ -18,13 +18,23 @@
static DEFINE_SPINLOCK(krait_clock_reg_lock);

#define LPL_SHIFT 8
+#define SECCLKAGD BIT(4)
+
static void __krait_mux_set_sel(struct krait_mux_clk *mux, int sel)
{
unsigned long flags;
u32 regval;

spin_lock_irqsave(&krait_clock_reg_lock, flags);
+
regval = krait_get_l2_indirect_reg(mux->offset);
+
+ /* apq/ipq8064 Errata: disable sec_src clock gating during switch. */
+ if (mux->disable_sec_src_gating) {
+ regval |= SECCLKAGD;
+ krait_set_l2_indirect_reg(mux->offset, regval);
+ }
+
regval &= ~(mux->mask << mux->shift);
regval |= (sel & mux->mask) << mux->shift;
if (mux->lpl) {
@@ -33,6 +43,12 @@ static void __krait_mux_set_sel(struct krait_mux_clk *mux, int sel)
}
krait_set_l2_indirect_reg(mux->offset, regval);

+ /* apq/ipq8064 Errata: re-enabled sec_src clock gating. */
+ if (mux->disable_sec_src_gating) {
+ regval &= ~SECCLKAGD;
+ krait_set_l2_indirect_reg(mux->offset, regval);
+ }
+
/* Wait for switch to complete. */
mb();
udelay(1);
diff --git a/drivers/clk/qcom/clk-krait.h b/drivers/clk/qcom/clk-krait.h
index 9120bd2f5297..f930538c539e 100644
--- a/drivers/clk/qcom/clk-krait.h
+++ b/drivers/clk/qcom/clk-krait.h
@@ -15,6 +15,7 @@ struct krait_mux_clk {
u8 safe_sel;
u8 old_index;
bool reparent;
+ bool disable_sec_src_gating;

struct clk_hw hw;
struct notifier_block clk_nb;
diff --git a/drivers/clk/qcom/krait-cc.c b/drivers/clk/qcom/krait-cc.c
index 299eb4c81d96..cb8b267f1dc5 100644
--- a/drivers/clk/qcom/krait-cc.c
+++ b/drivers/clk/qcom/krait-cc.c
@@ -157,6 +157,7 @@ krait_add_sec_mux(struct device *dev, struct clk *qsb, int id,
mux->shift = 2;
mux->parent_map = sec_mux_map;
mux->hw.init = &init;
+ mux->disable_sec_src_gating = true;

init.name = kasprintf(GFP_KERNEL, "krait%s_sec_mux", s);
if (!init.name)
--
2.34.1