From 898d0d6483a9360f1968e0a900465c1fa152a4a9 Mon Sep 17 00:00:00 2001 From: Ansuel Smith Date: Sat, 30 Apr 2022 07:44:58 +0200 Subject: [PATCH 3/3] clk: qcom: clk-krait: add apq/ipq8064 errata workaround Add apq/ipq8064 errata workaround where the sec_src clock gating needs to be disabled during switching. krait-cc compatible is not enough to handle this and limit this workaround to apq/ipq8064. We check machine compatible to handle this. Signed-off-by: Ansuel Smith Reviewed-by: Dmitry Baryshkov Signed-off-by: Bjorn Andersson Link: https://lore.kernel.org/r/20220430054458.31321-4-ansuelsmth@gmail.com --- drivers/clk/qcom/clk-krait.c | 16 ++++++++++++++++ drivers/clk/qcom/clk-krait.h | 1 + drivers/clk/qcom/krait-cc.c | 8 ++++++++ 3 files changed, 25 insertions(+) --- 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 k } 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); --- 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; --- a/drivers/clk/qcom/krait-cc.c +++ b/drivers/clk/qcom/krait-cc.c @@ -139,6 +139,14 @@ krait_add_sec_mux(struct device *dev, in mux->hw.init = &init; mux->safe_sel = 0; + /* Checking for qcom,krait-cc-v1 or qcom,krait-cc-v2 is not + * enough to limit this to apq/ipq8064. Directly check machine + * compatible to correctly handle this errata. + */ + if (of_machine_is_compatible("qcom,ipq8064") || + of_machine_is_compatible("qcom,apq8064")) + mux->disable_sec_src_gating = true; + init.name = kasprintf(GFP_KERNEL, "krait%s_sec_mux", s); if (!init.name) return -ENOMEM;