Re: [PATCH v6 06/19] soc: tegra: Add Tegra PMC clocks registration into PMC driver

Dmitry Osipenko
2020-01-08T01:00:34Z

07.01.2020 07:14, Sowjanya Komatineni пишет:
> Tegra PMC has clk_out_1, clk_out_2, and clk_out_3 clocks and currently
> these PMC clocks are registered by Tegra clock driver with each clock as
> separate mux and gate clocks using clk_register_mux and clk_register_gate
> by passing PMC base address and register offsets and PMC programming for
> these clocks happens through direct PMC access by the clock driver.
>
> With this, when PMC is in secure mode any direct PMC access from the
> non-secure world does not go through and these clocks will not be
> functional.
>
> This patch adds these PMC clocks registration to pmc driver with PMC as
> a clock provider and registers each clock as single clock.
>
> clk_ops callback implementations for these clocks uses tegra_pmc_readl and
> tegra_pmc_writel which supports PMC programming in both secure mode and
> non-secure mode.
>
> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
> ---
> drivers/soc/tegra/pmc.c | 242 ++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 242 insertions(+)
>
> diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c
> index 1699dda6b393..2b1a709c3cb7 100644
> --- a/drivers/soc/tegra/pmc.c
> +++ b/drivers/soc/tegra/pmc.c
> @@ -13,9 +13,13 @@
>
> #include <linux/arm-smccc.h>
> #include <linux/clk.h>
> +#include <linux/clk-provider.h>
> +#include <linux/clkdev.h>
> +#include <linux/clk/clk-conf.h>
> #include <linux/clk/tegra.h>
> #include <linux/debugfs.h>
> #include <linux/delay.h>
> +#include <linux/device.h>
> #include <linux/err.h>
> #include <linux/export.h>
> #include <linux/init.h>
> @@ -48,6 +52,7 @@
> #include <dt-bindings/pinctrl/pinctrl-tegra-io-pad.h>
> #include <dt-bindings/gpio/tegra186-gpio.h>
> #include <dt-bindings/gpio/tegra194-gpio.h>
> +#include <dt-bindings/soc/tegra-pmc.h>
>
> #define PMC_CNTRL 0x0
> #define PMC_CNTRL_INTR_POLARITY BIT(17) /* inverts INTR polarity */
> @@ -100,6 +105,8 @@
> #define PMC_WAKE2_STATUS 0x168
> #define PMC_SW_WAKE2_STATUS 0x16c
>
> +#define PMC_CLK_OUT_CNTRL 0x1a8
> +#define PMC_CLK_OUT_MUX_MASK GENMASK(1, 0)
> #define PMC_SENSOR_CTRL 0x1b0
> #define PMC_SENSOR_CTRL_SCRATCH_WRITE BIT(2)
> #define PMC_SENSOR_CTRL_ENABLE_RST BIT(1)
> @@ -155,6 +162,63 @@
> #define TEGRA_SMC_PMC_READ 0xaa
> #define TEGRA_SMC_PMC_WRITE 0xbb
>
> +struct pmc_clk {
> + struct clk_hw hw;
> + unsigned long offs;
> + u32 mux_shift;
> + u32 force_en_shift;
> +};
> +
> +#define to_pmc_clk(_hw) container_of(_hw, struct pmc_clk, hw)
> +
> +struct pmc_clk_init_data {
> + char *name;
> + const char *const *parents;
> + int num_parents;
> + int clk_id;
> + u8 mux_shift;
> + u8 force_en_shift;
> +};
> +
> +static const char * const clk_out1_parents[] = { "osc", "osc_div2",
> + "osc_div4", "extern1",
> +};
> +
> +static const char * const clk_out2_parents[] = { "osc", "osc_div2",
> + "osc_div4", "extern2",
> +};
> +
> +static const char * const clk_out3_parents[] = { "osc", "osc_div2",
> + "osc_div4", "extern3",
> +};

There is no way to specify "osc" as a parent clock in a device-tree
because there is no DT ID assigned to the OSC in the CaR driver, should
this be fixed?