diff options
-rw-r--r-- | Documentation/devicetree/bindings/clock/clock-bindings.txt | 16 | ||||
-rw-r--r-- | drivers/clk/qcom/common.c | 18 |
2 files changed, 34 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/clock/clock-bindings.txt b/Documentation/devicetree/bindings/clock/clock-bindings.txt index 2ec489eebe72..b646bbcf7f92 100644 --- a/Documentation/devicetree/bindings/clock/clock-bindings.txt +++ b/Documentation/devicetree/bindings/clock/clock-bindings.txt @@ -168,3 +168,19 @@ a shared clock is forbidden. Configuration of common clocks, which affect multiple consumer devices can be similarly specified in the clock provider node. + +==Protected clocks== + +Some platforms or firmwares may not fully expose all the clocks to the OS, such +as in situations where those clks are used by drivers running in ARM secure +execution levels. Such a configuration can be specified in device tree with the +protected-clocks property in the form of a clock specifier list. This property should +only be specified in the node that is providing the clocks being protected: + + clock-controller@a000f000 { + compatible = "vendor,clk95; + reg = <0xa000f000 0x1000> + #clocks-cells = <1>; + ... + protected-clocks = <UART3_CLK>, <SPI5_CLK>; + }; diff --git a/drivers/clk/qcom/common.c b/drivers/clk/qcom/common.c index db9b2471ac40..0a48ed56833b 100644 --- a/drivers/clk/qcom/common.c +++ b/drivers/clk/qcom/common.c @@ -191,6 +191,22 @@ int qcom_cc_register_sleep_clk(struct device *dev) } EXPORT_SYMBOL_GPL(qcom_cc_register_sleep_clk); +/* Drop 'protected-clocks' from the list of clocks to register */ +static void qcom_cc_drop_protected(struct device *dev, struct qcom_cc *cc) +{ + struct device_node *np = dev->of_node; + struct property *prop; + const __be32 *p; + u32 i; + + of_property_for_each_u32(np, "protected-clocks", prop, p, i) { + if (i >= cc->num_rclks) + continue; + + cc->rclks[i] = NULL; + } +} + static struct clk_hw *qcom_cc_clk_hw_get(struct of_phandle_args *clkspec, void *data) { @@ -251,6 +267,8 @@ int qcom_cc_really_probe(struct platform_device *pdev, cc->rclks = rclks; cc->num_rclks = num_clks; + qcom_cc_drop_protected(dev, cc); + for (i = 0; i < num_clks; i++) { if (!rclks[i]) continue; |