Add a stub clock driver which can be used to bind clock controllers which aren't required for the platform to boot, but which are needed for U-Boot drivers to work.

In addition, add a NOP parent driver to allow for binding the parent nodes of the clock.

Initially this driver supports a Qualcomm platform where the MMC driver tries to fetch the RPM clock controller, which is not actually required for the device to work.

Reviewed-by: Neil Armstrong neil.armstrong@linaro.org Acked-by: Ilias Apalodimas ilias.apalodimas@linaro.org Signed-off-by: Caleb Connolly caleb.connolly@linaro.org --- drivers/clk/Kconfig | 7 ++++++ drivers/clk/Makefile | 1 + drivers/clk/clk-stub.c | 66 ++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 74 insertions(+)

diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig index 9acbc47fe8ed..965bc4959403 100644 --- a/drivers/clk/Kconfig +++ b/drivers/clk/Kconfig @@ -95,8 +95,15 @@ config SPL_CLK_GPIO help Enable this option to add GPIO-controlled clock gate driver in U-Boot SPL.

+config CLK_STUB + bool "Stub clock driver" + depends on CLK + help + Enable this to provide a stub clock driver for non-essential clock + controllers. + config CLK_BCM6345 bool "Clock controller driver for BCM6345" depends on CLK && ARCH_BMIPS default y diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile index 847b9b291100..b2cea41419b7 100644 --- a/drivers/clk/Makefile +++ b/drivers/clk/Makefile @@ -10,8 +10,9 @@ obj-$(CONFIG_$(SPL_TPL_)CLK) += clk_fixed_factor.o obj-$(CONFIG_$(SPL_TPL_)CLK_CCF) += clk.o clk-divider.o clk-mux.o clk-gate.o obj-$(CONFIG_$(SPL_TPL_)CLK_CCF) += clk-fixed-factor.o obj-$(CONFIG_$(SPL_TPL_)CLK_COMPOSITE_CCF) += clk-composite.o obj-$(CONFIG_$(SPL_TPL_)CLK_GPIO) += clk-gpio.o +obj-$(CONFIG_CLK_STUB) += clk-stub.o

obj-y += adi/ obj-y += analogbits/ obj-y += imx/ diff --git a/drivers/clk/clk-stub.c b/drivers/clk/clk-stub.c new file mode 100644 index 000000000000..ea817031fa6c --- /dev/null +++ b/drivers/clk/clk-stub.c @@ -0,0 +1,66 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Stub clk driver for non-essential clocks. + * + * This driver should be used for clock controllers + * which are described as dependencies in DT but aren't + * actually necessary for hardware functionality. + */ + +#include <clk-uclass.h> +#include <dm.h> + +/* NOP parent nodes to stub clocks */ +static const struct udevice_id nop_parent_ids[] = { + { .compatible = "qcom,rpm-proc" }, + { .compatible = "qcom,glink-rpm" }, + { .compatible = "qcom,rpm-sm6115" }, + { } +}; + +U_BOOT_DRIVER(nop_parent) = { + .name = "nop_parent", + .id = UCLASS_NOP, + .of_match = nop_parent_ids, + .bind = dm_scan_fdt_dev, + .flags = DM_FLAG_DEFAULT_PD_CTRL_OFF, +}; + +static ulong stub_clk_set_rate(struct clk *clk, ulong rate) +{ + return (clk->rate = rate); +} + +static ulong stub_clk_get_rate(struct clk *clk) +{ + return clk->rate; +} + +static int stub_clk_nop(struct clk *clk) +{ + return 0; +} + +static struct clk_ops stub_clk_ops = { + .set_rate = stub_clk_set_rate, + .get_rate = stub_clk_get_rate, + .enable = stub_clk_nop, + .disable = stub_clk_nop, +}; + +static const struct udevice_id stub_clk_ids[] = { + { .compatible = "qcom,rpmcc" }, + { .compatible = "qcom,sm8250-rpmh-clk" }, + { .compatible = "qcom,sm8550-rpmh-clk" }, + { .compatible = "qcom,sm8650-rpmh-clk" }, + { } +}; + +U_BOOT_DRIVER(clk_stub) = { + .name = "clk_stub", + .id = UCLASS_CLK, + .ops = &stub_clk_ops, + .of_match = stub_clk_ids, + .flags = DM_FLAG_DEFAULT_PD_CTRL_OFF, +}; +