Commit 04577994 authored by Haojian Zhuang's avatar Haojian Zhuang Committed by Mike Turquette

clk: gate: add CLK_GATE_HIWORD_MASK

In Rockchip Cortex-A9 based chips, they don't use paradigm of
reading-changing-writing the register contents.  Instead they
use a hiword mask to indicate the changed bits.

When b1 should be set as gate, it also needs to indicate the change
by setting hiword mask (b1 << 16).

The patch adds gate flag for this usage.
Signed-off-by: default avatarHeiko Stuebner <>
Signed-off-by: default avatarHaojian Zhuang <>
Signed-off-by: default avatarMike Turquette <>
parent d57dfe75
......@@ -53,12 +53,18 @@ static void clk_gate_endisable(struct clk_hw *hw, int enable)
if (gate->lock)
spin_lock_irqsave(gate->lock, flags);
reg = readl(gate->reg);
if (set)
reg |= BIT(gate->bit_idx);
reg &= ~BIT(gate->bit_idx);
if (gate->flags & CLK_GATE_HIWORD_MASK) {
reg = BIT(gate->bit_idx + 16);
if (set)
reg |= BIT(gate->bit_idx);
} else {
reg = readl(gate->reg);
if (set)
reg |= BIT(gate->bit_idx);
reg &= ~BIT(gate->bit_idx);
writel(reg, gate->reg);
......@@ -121,6 +127,13 @@ struct clk *clk_register_gate(struct device *dev, const char *name,
struct clk *clk;
struct clk_init_data init;
if (clk_gate_flags & CLK_GATE_HIWORD_MASK) {
if (bit_idx > 16) {
pr_err("gate bit exceeds LOWORD field\n");
return ERR_PTR(-EINVAL);
/* allocate the gate */
gate = kzalloc(sizeof(struct clk_gate), GFP_KERNEL);
if (!gate) {
......@@ -210,6 +210,10 @@ void of_fixed_clk_setup(struct device_node *np);
* CLK_GATE_SET_TO_DISABLE - by default this clock sets the bit at bit_idx to
* enable the clock. Setting this flag does the opposite: setting the bit
* disable the clock and clearing it enables the clock
* CLK_GATE_HIWORD_MASK - The gate settings are only in lower 16-bit
* of this register, and mask of gate bits are in higher 16-bit of this
* register. While setting the gate bits, higher 16-bit should also be
* updated to indicate changing gate bits.
struct clk_gate {
struct clk_hw hw;
......@@ -220,6 +224,7 @@ struct clk_gate {
extern const struct clk_ops clk_gate_ops;
struct clk *clk_register_gate(struct device *dev, const char *name,
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