Re: [PATCH v2 02/11] soc: tegra: Add Tegra PMC clock registrations into PMC driver

[Sowjanya Komatineni <skomatineni@nvidia.com>]

On 12/4/19 12:28 PM, Dmitry Osipenko wrote:
> 04.12.2019 23:08, Sowjanya Komatineni пишет:
>> On 12/4/19 8:02 AM, Sowjanya Komatineni wrote:
>>> On 12/4/19 5:39 AM, Dmitry Osipenko wrote:
>>>> 03.12.2019 19:45, Sowjanya Komatineni пишет:
>>>>> On 12/2/19 4:07 PM, Sowjanya Komatineni wrote:
>>>>>> On 12/2/19 3:14 PM, Sowjanya Komatineni wrote:
>>>>>>> On 12/2/19 3:10 PM, Sowjanya Komatineni wrote:
>>>>>>>> On 12/2/19 2:58 PM, Sowjanya Komatineni wrote:
>>>>>>>>> On 12/2/19 1:50 PM, Dmitry Osipenko wrote:
>>>>>>>>>> 02.12.2019 23:09, Sowjanya Komatineni пишет:
>>>>>>>>>>> On 11/28/19 5:25 AM, Dmitry Osipenko wrote:
>>>>>>>>>>>> 28.11.2019 01:57, Sowjanya Komatineni пишет:
>>>>>>>>>>>>> On 11/27/19 7:14 AM, Dmitry Osipenko wrote:
>>>>>>>>>>>>>> 27.11.2019 07:59, Sowjanya Komatineni пишет:
>>>>>>>>>>>>>>> Tegra210 and prior Tegra PMC has clk_out_1, clk_out_2,
>>>>>>>>>>>>>>> clk_out_3 with
>>>>>>>>>>>>>>> mux and gate for each of these clocks.
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> Currently these PMC clocks are registered by Tegra clock
>>>>>>>>>>>>>>> driver 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 clocks registration with PMC as a clock
>>>>>>>>>>>>>>> provider
>>>>>>>>>>>>>>> for these clocks. clk_ops callback implementations for these
>>>>>>>>>>>>>>> clocks
>>>>>>>>>>>>>>> uses tegra_pmc_readl and tegra_pmc_writel which supports PMC
>>>>>>>>>>>>>>> programming
>>>>>>>>>>>>>>> in secure mode and non-secure mode.
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
>>>>>>>>>>>>>>> ---
>>>>>>>>>>>>>>>       drivers/soc/tegra/pmc.c | 330
>>>>>>>>>>>>>>> ++++++++++++++++++++++++++++++++++++++++++++++++
>>>>>>>>>>>>>>>       1 file changed, 330 insertions(+)
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> diff --git a/drivers/soc/tegra/pmc.c
>>>>>>>>>>>>>>> b/drivers/soc/tegra/pmc.c
>>>>>>>>>>>>>>> index ea0e11a09c12..a353f6d0a832 100644
>>>>>>>>>>>>>>> --- a/drivers/soc/tegra/pmc.c
>>>>>>>>>>>>>>> +++ b/drivers/soc/tegra/pmc.c
>>>>>>>>>>>>>>> @@ -13,6 +13,9 @@
>>>>>>>>>>>>>>>         #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>
>>>>>>>>>>>>>>> @@ -48,6 +51,7 @@
>>>>>>>>>>>>>>>       #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 +104,7 @@
>>>>>>>>>>>>>>>       #define PMC_WAKE2_STATUS        0x168
>>>>>>>>>>>>>>>       #define PMC_SW_WAKE2_STATUS 0x16c
>>>>>>>>>>>>>>>       +#define PMC_CLK_OUT_CNTRL 0x1a8
>>>>>>>>>>>>>>>       #define PMC_SENSOR_CTRL 0x1b0
>>>>>>>>>>>>>>>       #define PMC_SENSOR_CTRL_SCRATCH_WRITE BIT(2)
>>>>>>>>>>>>>>>       #define  PMC_SENSOR_CTRL_ENABLE_RST BIT(1)
>>>>>>>>>>>>>>> @@ -155,6 +160,91 @@
>>>>>>>>>>>>>>>       #define  TEGRA_SMC_PMC_READ    0xaa
>>>>>>>>>>>>>>>       #define  TEGRA_SMC_PMC_WRITE    0xbb
>>>>>>>>>>>>>>>       +struct pmc_clk_mux {
>>>>>>>>>>>>>>> +    struct clk_hw    hw;
>>>>>>>>>>>>>>> +    unsigned long    offs;
>>>>>>>>>>>>>>> +    u32        mask;
>>>>>>>>>>>>>>> +    u32        shift;
>>>>>>>>>>>>>>> +};
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +#define to_pmc_clk_mux(_hw) container_of(_hw, struct
>>>>>>>>>>>>>>> pmc_clk_mux, hw)
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +struct pmc_clk_gate {
>>>>>>>>>>>>>>> +    struct clk_hw    hw;
>>>>>>>>>>>>>>> +    unsigned long    offs;
>>>>>>>>>>>>>>> +    u32        shift;
>>>>>>>>>>>>>>> +};
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +#define to_pmc_clk_gate(_hw) container_of(_hw, struct
>>>>>>>>>>>>>>> pmc_clk_gate, hw)
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +struct pmc_clk_init_data {
>>>>>>>>>>>>>>> +    char *mux_name;
>>>>>>>>>>>>>>> +    char *gate_name;
>>>>>>>>>>>>>>> +    const char **parents;
>>>>>>>>>>>>>>> +    int num_parents;
>>>>>>>>>>>>>>> +    int mux_id;
>>>>>>>>>>>>>>> +    int gate_id;
>>>>>>>>>>>>>>> +    char *dev_name;
>>>>>>>>>>>>>>> +    u8 mux_shift;
>>>>>>>>>>>>>>> +    u8 gate_shift;
>>>>>>>>>>>>>>> +    u8 init_parent_index;
>>>>>>>>>>>>>>> +    int init_state;
>>>>>>>>>>>>>>> +};
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +static const char *clk_out1_parents[] = { "clk_m",
>>>>>>>>>>>>>>> "clk_m_div2",
>>>>>>>>>>>>>>> +    "clk_m_div4", "extern1",
>>>>>>>>>>>>>>> +};
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +static const char *clk_out2_parents[] = { "clk_m",
>>>>>>>>>>>>>>> "clk_m_div2",
>>>>>>>>>>>>>>> +    "clk_m_div4", "extern2",
>>>>>>>>>>>>>>> +};
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +static const char *clk_out3_parents[] = { "clk_m",
>>>>>>>>>>>>>>> "clk_m_div2",
>>>>>>>>>>>>>>> +    "clk_m_div4", "extern3",
>>>>>>>>>>>>>>> +};
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +static struct pmc_clk_init_data tegra_pmc_clks_data[] = {
>>>>>>>>>>>>>>> +    {
>>>>>>>>>>>>>>> +        .mux_name = "clk_out_1_mux",
>>>>>>>>>>>>>>> +        .gate_name = "clk_out_1",
>>>>>>>>>>>>>>> +        .parents = clk_out1_parents,
>>>>>>>>>>>>>>> +        .num_parents = ARRAY_SIZE(clk_out1_parents),
>>>>>>>>>>>>>>> +        .mux_id = TEGRA_PMC_CLK_OUT_1_MUX,
>>>>>>>>>>>>>>> +        .gate_id = TEGRA_PMC_CLK_OUT_1,
>>>>>>>>>>>>>>> +        .dev_name = "extern1",
>>>>>>>>>>>>>>> +        .mux_shift = 6,
>>>>>>>>>>>>>>> +        .gate_shift = 2,
>>>>>>>>>>>>>>> +        .init_parent_index = 3,
>>>>>>>>>>>>>>> +        .init_state = 1,
>>>>>>>>>>>>>>> +    },
>>>>>>>>>>>>>>> +    {
>>>>>>>>>>>>>>> +        .mux_name = "clk_out_2_mux",
>>>>>>>>>>>>>>> +        .gate_name = "clk_out_2",
>>>>>>>>>>>>>>> +        .parents = clk_out2_parents,
>>>>>>>>>>>>>>> +        .num_parents = ARRAY_SIZE(clk_out2_parents),
>>>>>>>>>>>>>>> +        .mux_id = TEGRA_PMC_CLK_OUT_2_MUX,
>>>>>>>>>>>>>>> +        .gate_id = TEGRA_PMC_CLK_OUT_2,
>>>>>>>>>>>>>>> +        .dev_name = "extern2",
>>>>>>>>>>>>>>> +        .mux_shift = 14,
>>>>>>>>>>>>>>> +        .gate_shift = 10,
>>>>>>>>>>>>>>> +        .init_parent_index = 0,
>>>>>>>>>>>>>>> +        .init_state = 0,
>>>>>>>>>>>>>>> +    },
>>>>>>>>>>>>>>> +    {
>>>>>>>>>>>>>>> +        .mux_name = "clk_out_3_mux",
>>>>>>>>>>>>>>> +        .gate_name = "clk_out_3",
>>>>>>>>>>>>>>> +        .parents = clk_out3_parents,
>>>>>>>>>>>>>>> +        .num_parents = ARRAY_SIZE(clk_out3_parents),
>>>>>>>>>>>>>>> +        .mux_id = TEGRA_PMC_CLK_OUT_3_MUX,
>>>>>>>>>>>>>>> +        .gate_id = TEGRA_PMC_CLK_OUT_3,
>>>>>>>>>>>>>>> +        .dev_name = "extern3",
>>>>>>>>>>>>>>> +        .mux_shift = 22,
>>>>>>>>>>>>>>> +        .gate_shift = 18,
>>>>>>>>>>>>>>> +        .init_parent_index = 0,
>>>>>>>>>>>>>>> +        .init_state = 0,
>>>>>>>>>>>>>>> +    },
>>>>>>>>>>>>>>> +};
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>>       struct tegra_powergate {
>>>>>>>>>>>>>>>           struct generic_pm_domain genpd;
>>>>>>>>>>>>>>>           struct tegra_pmc *pmc;
>>>>>>>>>>>>>>> @@ -254,6 +344,9 @@ struct tegra_pmc_soc {
>>>>>>>>>>>>>>>            */
>>>>>>>>>>>>>>>           const struct tegra_wake_event *wake_events;
>>>>>>>>>>>>>>>           unsigned int num_wake_events;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    struct pmc_clk_init_data *pmc_clks_data;
>>>>>>>>>>>>>>> +    unsigned int num_pmc_clks;
>>>>>>>>>>>>>>>       };
>>>>>>>>>>>>>>>         static const char * const tegra186_reset_sources[] = {
>>>>>>>>>>>>>>> @@ -2163,6 +2256,228 @@ static int
>>>>>>>>>>>>>>> tegra_pmc_clk_notify_cb(struct
>>>>>>>>>>>>>>> notifier_block *nb,
>>>>>>>>>>>>>>>           return NOTIFY_OK;
>>>>>>>>>>>>>>>       }
>>>>>>>>>>>>>>>       +static void pmc_clk_fence_udelay(u32 offset)
>>>>>>>>>>>>>>> +{
>>>>>>>>>>>>>>> +    tegra_pmc_readl(pmc, offset);
>>>>>>>>>>>>>>> +    /* pmc clk propagation delay 2 us */
>>>>>>>>>>>>>>> +    udelay(2);
>>>>>>>>>>>>>>> +}
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +static u8 pmc_clk_mux_get_parent(struct clk_hw *hw)
>>>>>>>>>>>>>>> +{
>>>>>>>>>>>>>>> +    struct pmc_clk_mux *mux = to_pmc_clk_mux(hw);
>>>>>>>>>>>>>>> +    int num_parents = clk_hw_get_num_parents(hw);
>>>>>>>>>>>>>>> +    u32 val;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    val = tegra_pmc_readl(pmc, mux->offs) >> mux->shift;
>>>>>>>>>>>>>>> +    val &= mux->mask;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    if (val >= num_parents)
>>>>>>>>>>>>>>> +        return -EINVAL;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    return val;
>>>>>>>>>>>>>>> +}
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +static int pmc_clk_mux_set_parent(struct clk_hw *hw, u8
>>>>>>>>>>>>>>> index)
>>>>>>>>>>>>>>> +{
>>>>>>>>>>>>>>> +    struct pmc_clk_mux *mux = to_pmc_clk_mux(hw);
>>>>>>>>>>>>>>> +    u32 val;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    val = tegra_pmc_readl(pmc, mux->offs);
>>>>>>>>>>>>>>> +    val &= ~(mux->mask << mux->shift);
>>>>>>>>>>>>>>> +    val |= index << mux->shift;
>>>>>>>>>>>>>>> +    tegra_pmc_writel(pmc, val, mux->offs);
>>>>>>>>>>>>>>> +    pmc_clk_fence_udelay(mux->offs);
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    return 0;
>>>>>>>>>>>>>>> +}
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +static const struct clk_ops pmc_clk_mux_ops = {
>>>>>>>>>>>>>>> +    .get_parent = pmc_clk_mux_get_parent,
>>>>>>>>>>>>>>> +    .set_parent = pmc_clk_mux_set_parent,
>>>>>>>>>>>>>>> +    .determine_rate = __clk_mux_determine_rate,
>>>>>>>>>>>>>>> +};
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +static struct clk *
>>>>>>>>>>>>>>> +tegra_pmc_clk_mux_register(const char *name, const char *
>>>>>>>>>>>>>>> const
>>>>>>>>>>>>>>> *parent_names,
>>>>>>>>>>>>>>> +               int num_parents, unsigned long flags,
>>>>>>>>>>>>>>> +               unsigned long offset, u32 shift, u32 mask)
>>>>>>>>>>>>>>> +{
>>>>>>>>>>>>>>> +    struct clk_init_data init;
>>>>>>>>>>>>>>> +    struct pmc_clk_mux *mux;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    mux = kzalloc(sizeof(*mux), GFP_KERNEL);
>>>>>>>>>>>>>>> +    if (!mux)
>>>>>>>>>>>>>>> +        return ERR_PTR(-ENOMEM);
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    init.name = name;
>>>>>>>>>>>>>>> +    init.ops = &pmc_clk_mux_ops;
>>>>>>>>>>>>>>> +    init.parent_names = parent_names;
>>>>>>>>>>>>>>> +    init.num_parents = num_parents;
>>>>>>>>>>>>>>> +    init.flags = flags;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    mux->hw.init = &init;
>>>>>>>>>>>>>>> +    mux->offs = offset;
>>>>>>>>>>>>>>> +    mux->mask = mask;
>>>>>>>>>>>>>>> +    mux->shift = shift;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    return clk_register(NULL, &mux->hw);
>>>>>>>>>>>>>>> +}
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +static int pmc_clk_is_enabled(struct clk_hw *hw)
>>>>>>>>>>>>>>> +{
>>>>>>>>>>>>>>> +    struct pmc_clk_gate *gate = to_pmc_clk_gate(hw);
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    return tegra_pmc_readl(pmc, gate->offs) &
>>>>>>>>>>>>>>> BIT(gate->shift) ? 1
>>>>>>>>>>>>>>> : 0;
>>>>>>>>>>>>>>> +}
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +static void pmc_clk_set_state(struct clk_hw *hw, int state)
>>>>>>>>>>>>>>> +{
>>>>>>>>>>>>>>> +    struct pmc_clk_gate *gate = to_pmc_clk_gate(hw);
>>>>>>>>>>>>>>> +    u32 val;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    val = tegra_pmc_readl(pmc, gate->offs);
>>>>>>>>>>>>>>> +    val = state ? (val | BIT(gate->shift)) : (val &
>>>>>>>>>>>>>>> ~BIT(gate->shift));
>>>>>>>>>>>>>>> +    tegra_pmc_writel(pmc, val, gate->offs);
>>>>>>>>>>>>>>> +    pmc_clk_fence_udelay(gate->offs);
>>>>>>>>>>>>>>> +}
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +static int pmc_clk_enable(struct clk_hw *hw)
>>>>>>>>>>>>>>> +{
>>>>>>>>>>>>>>> +    pmc_clk_set_state(hw, 1);
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    return 0;
>>>>>>>>>>>>>>> +}
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +static void pmc_clk_disable(struct clk_hw *hw)
>>>>>>>>>>>>>>> +{
>>>>>>>>>>>>>>> +    pmc_clk_set_state(hw, 0);
>>>>>>>>>>>>>>> +}
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +static const struct clk_ops pmc_clk_gate_ops = {
>>>>>>>>>>>>>>> +    .is_enabled = pmc_clk_is_enabled,
>>>>>>>>>>>>>>> +    .enable = pmc_clk_enable,
>>>>>>>>>>>>>>> +    .disable = pmc_clk_disable,
>>>>>>>>>>>>>>> +};
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +static struct clk *
>>>>>>>>>>>>>>> +tegra_pmc_clk_gate_register(const char *name, const char
>>>>>>>>>>>>>>> *parent_name,
>>>>>>>>>>>>>>> +                unsigned long flags, unsigned long offset,
>>>>>>>>>>>>>>> +                u32 shift)
>>>>>>>>>>>>>>> +{
>>>>>>>>>>>>>>> +    struct clk_init_data init;
>>>>>>>>>>>>>>> +    struct pmc_clk_gate *gate;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    gate = kzalloc(sizeof(*gate), GFP_KERNEL);
>>>>>>>>>>>>>>> +    if (!gate)
>>>>>>>>>>>>>>> +        return ERR_PTR(-ENOMEM);
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    init.name = name;
>>>>>>>>>>>>>>> +    init.ops = &pmc_clk_gate_ops;
>>>>>>>>>>>>>>> +    init.parent_names = &parent_name;
>>>>>>>>>>>>>>> +    init.num_parents = 1;
>>>>>>>>>>>>>>> +    init.flags = flags;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    gate->hw.init = &init;
>>>>>>>>>>>>>>> +    gate->offs = offset;
>>>>>>>>>>>>>>> +    gate->shift = shift;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    return clk_register(NULL, &gate->hw);
>>>>>>>>>>>>>>> +}
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +static void tegra_pmc_clock_register(struct tegra_pmc *pmc,
>>>>>>>>>>>>>>> +                     struct device_node *np)
>>>>>>>>>>>>>>> +{
>>>>>>>>>>>>>>> +    struct clk *clkmux, *clk, *parent;
>>>>>>>>>>>>>>> +    struct clk_onecell_data *clk_data;
>>>>>>>>>>>>>>> +    unsigned int num_clks;
>>>>>>>>>>>>>>> +    int i, ret;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    /* each pmc clock output has a mux and a gate */
>>>>>>>>>>>>>>> +    num_clks = pmc->soc->num_pmc_clks * 2;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    if (!num_clks)
>>>>>>>>>>>>>>> +        return;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    clk_data = kmalloc(sizeof(*clk_data), GFP_KERNEL);
>>>>>>>>>>>>>>> +    if (!clk_data)
>>>>>>>>>>>>>>> +        return;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    clk_data->clks = kcalloc(TEGRA_PMC_CLK_MAX,
>>>>>>>>>>>>>>> sizeof(*clk_data->clks),
>>>>>>>>>>>>>>> +                 GFP_KERNEL);
>>>>>>>>>>>>>>> +    if (!clk_data->clks)
>>>>>>>>>>>>>>> +        goto free_clkdata;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    clk_data->clk_num = num_clks;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +    for (i = 0; i < pmc->soc->num_pmc_clks; i++) {
>>>>>>>>>>>>>>> +        struct pmc_clk_init_data *data;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +        data = pmc->soc->pmc_clks_data + i;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +        clkmux = tegra_pmc_clk_mux_register(data->mux_name,
>>>>>>>>>>>>>>> + data->parents,
>>>>>>>>>>>>>>> + data->num_parents,
>>>>>>>>>>>>>>> + CLK_SET_RATE_NO_REPARENT |
>>>>>>>>>>>>>>> + CLK_SET_RATE_PARENT,
>>>>>>>>>>>>>>> + PMC_CLK_OUT_CNTRL,
>>>>>>>>>>>>>>> + data->mux_shift, 3);
>>>>>>>>>>>>>>> +        if (IS_ERR(clkmux))
>>>>>>>>>>>>>>> +            goto free_clks;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> + clk_data->clks[data->mux_id] = clkmux;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +        clk = tegra_pmc_clk_gate_register(data->gate_name,
>>>>>>>>>>>>>>> + data->mux_name,
>>>>>>>>>>>>>>> + CLK_SET_RATE_PARENT,
>>>>>>>>>>>>>>> + PMC_CLK_OUT_CNTRL,
>>>>>>>>>>>>>>> + data->gate_shift);
>>>>>>>>>>>>>>> +        if (IS_ERR(clk))
>>>>>>>>>>>>>>> +            goto free_clks;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> + clk_data->clks[data->gate_id] = clk;
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +        ret = clk_set_parent(clk, clkmux);
>>>>>>>>>>>>>>> +        if (ret < 0) {
>>>>>>>>>>>>>>> +            pr_err("failed to set parent of %s to %s\n",
>>>>>>>>>>>>>>> +                   __func__, __clk_get_name(clk),
>>>>>>>>>>>>>>> + __clk_get_name(clkmux));
>>>>>>>>>>>>>>> +        }
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +        clk_register_clkdev(clk, data->dev_name,
>>>>>>>>>>>>>>> data->gate_name);
>>>>>>>>>>>>>>> +
>>>>>>>>>>>>>>> +        /* configure initial clock parent and state */
>>>>>>>>>>>>>>> +        parent = clk_get_sys(data->gate_name,
>>>>>>>>>>>>>>> + data->parents[data->init_parent_index]);
>>>>>>>>>> Couldn't the default parent be defined using "assigned clock" in a
>>>>>>>>>> device-tree? Please see "Assigned clock parents and rates" in the
>>>>>>>>>> doc.
>>>>>>>>>>
>>>>>>>>>> https://www.kernel.org/doc/Documentation/devicetree/bindings/clock/clock-bindings.txt
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> Then you could simply use of_clk_set_defaults(pmc->dev->of_node,
>>>>>>>>>> true).
>>>>>>>>> Yes, of_clk_add_provider() does of_clk_set_defaults which sets
>>>>>>>>> based on assigned parents and clock rates.
>>>>>>>>>
>>>>>>>>> This need device tree to specify assigned clock parent properties.
>>>>>>>>> Will update device tree and remove init parent from the driver.
>>>>>>>>>
>>>>>>>> assigned-clock properties should be set in consumer node of these
>>>>>>>> clocks and currently these clocks are not used yet.
>>>>>>>>
>>>>>>>> So will just remove init parent from driver and when these clocks
>>>>>>>> are used device tree can be updated in corresponding consumer node
>>>>>>>> with these properties.
>>>>>>>>
>>>>>>> How about default ON/OFF init state for the clocks? I see
>>>>>>> assigned-clock properties for parent and rate only.
>>>>>>>
>>>>>>> But based on existing clock-tegra-pmc driver, I see clk_out_1 is
>>>>>>> default enabled with extern1 parent for T30 thru T210 platforms.
>>>>>>>
>>>>>>> Peter/Thierry, What was the reason we enable clk_out_1 right from the
>>>>>>> clock registration?
>>>>>>>
>>>>>> clk_out_1 is for audio and its not required to be enabled during the
>>>>>> boot and audio driver can enable/disable it.
>>>>>>
>>>>>> same with blink 32khz which is used for WIFI. WIFI driver can
>>>>>> enable/disable during power up/down sequence and technically as per
>>>>>> design we dont need to have it always on right from the boot.
>>>>>>
>>>>>> So can remove out clocks init states from driver once thierry also
>>>>>> agree on this.
>>>>>>
>>>>> Hi Dmitry,
>>>>>
>>>>> Looking at audio driver, it doesn't take care of mclk which is from
>>>>> clk_out_1 and expects mclk to be always on.
>>>>>
>>>>> So probably we should have this init state enables in pmc driver for
>>>>> 32Khz and clk_out's to not break existing functionality.
>>>> Hello Sowjanya,
>>>>
>>>> IIUC, it's a bug in the device-trees and sound's MCLK actually should be
>>>> set to CLK_OUT_1 of PMC instead of CaR's EXTPERIPH1. If that's the case,
>>>> then the device-trees need to be fixed.
>>> OK, will have this in v3
>> Actually if we change mclk to use clk_out_1, then it will break with old
>> device trees.
>>
>> Currently clk_out_1 parent is set to extern1 as init state by the clock
>> driver and device tree for sound node is using extern1 as mclk works and
>> extern1 itself has enable and disable. But yes implementation wise, its
>> incorrect as mclk should really be clk_out_1.
>>
>> Now, with moving clk_out_1 to tegra PMC, pmc is the clock provider and
>> if we now change the device tree to use CLK_OUT_1 as mclk then it will
>> break old device tree.
> There souldn't be any problem with enabling CLK_OUT_1 by the audio
> driver itself (in the code) if an old device-tree is detected.
>
> 	clk_out_1 = clk_get(dev, "clk_out_1");
> 	clk_set_parent(clk_out_1, clk_extern1);
> 	...
> 	data->clk_cdev1 = clk_out_1;
>
> Maybe it will be even better to compare clocks for detection of an older DT:
>
> 	if (tegra_get_chip_id() > TEGRA20 &&
> 	    clk_is_match(data->clk_cdev1, clk_extern1)) {
> 	...
>
we can do parent init in audio driver which is not an issue.

But I was saying we can keep extern1 as mclk in device tree instead of 
changing to clk_out_1 from pmc as it will break old device tree becasue 
we moved clk_out_1 from clock driver to pmc driver.

once we do init parent in audio driver, we still can use extern1 as mclk 
in device tree.

mclk -> clk_out_1 -> extern1 -> plla_out0 -> plla

with init of clk_out_1 parent to extern1, mclk can use extern1 handle 
for rate/enable/disable clk operations

>>>>> Regarding using assigned-clock properties for init parent and removing
>>>>> init parent from driver, it also needs consumer node in device tree to
>>>>> be updated to specify assigned-clock properties for default/init
>>>>> parent.
>>>>>
>>>>> This breaks device tree ABI as prior Tegra210 supports audio driver.
>>>> So it's the sound node which should have had the assigned clocks in
>>>> device-tree in order to define route for the audio MCLK clock from CaR
>>>> to PMC.
>>>>
>>>> Given that the audio clocks configuration is the same for all of the
>>>> currently supported boards, I think it will be better to remove the
>>>> entire audio clocks initialization from the clk drivers and move it all
>>>> to the audio driver. It could be something like this:
>>>>
>>>> int tegra_asoc_utils_init(struct tegra_asoc_utils_data *data,
>>>>                struct device *dev)
>>>> {
>>>>      ...
>>>>
>>>>      if (!of_find_property(dev->of_node, "assigned-clock-parents",
>>>> NULL) &&
>>>>          tegra_get_chip_id() > TEGRA20) {
>>>>          clk_extern1 = clk_get(dev, "extern1");
>>>>          ...
>>>>          clk_set_parent(clk_extern1, clk_pll_a_out0);
>>>>          ...
>>>>          clk_put(data->clk_cdev1);
>>>>
>>>>          data->clk_cdev1 = clk_out_1;
>>>>      }
>>>>      ...
>>>>
>>>> So now the old device-trees will cointinue to work and new could have
>>>> the assigned-clocks and set MCLK to CLK_OUT_1.
>>>>
>>>> [snip]
>>> Will update clk-tegra, pmc and audio driver to move init state
>>> configuration for extern1 and clk_out_1 into audio driver and will use
>>> assigned clock properties in device tree.
>>>