Re: [PATCH v1 06/17] soc: pmc: Add blink output clock registration to Tegra PMC

[Sowjanya Komatineni <skomatineni@nvidia.com>]

On 11/19/19 11:34 AM, Dmitry Osipenko wrote:
> 19.11.2019 09:50, Sowjanya Komatineni пишет:
>> Tegra PMC has blink control to output 32 Khz clock out to Tegra
>> blink pin. Blink pad DPD state and enable controls are part of
>> Tegra PMC register space.
>>
>> Currently Tegra clock driver registers blink control by passing
>> PMC address and register offset to clk_register_gate which performs
>> direct PMC access during clk_ops and with this when PMC is in secure
>> mode, any access from non-secure world does not go through.
>>
>> This patch adds blink control registration to the Tegra PMC driver
>> using PMC specific clock gate operations that use tegra_pmc_readl
>> and tegra_pmc_writel to support both secure mode and non-secure
>> mode PMC register access.
>>
>> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
>> ---
>>   drivers/soc/tegra/pmc.c | 42 ++++++++++++++++++++++++++++++++++++++++++
>>   1 file changed, 42 insertions(+)
>>
>> diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c
>> index 790a6619ba32..095e89c7fa3f 100644
>> --- a/drivers/soc/tegra/pmc.c
>> +++ b/drivers/soc/tegra/pmc.c
>> @@ -61,12 +61,15 @@
>>   #define  PMC_CNTRL_SYSCLK_OE		BIT(11) /* system clock enable */
>>   #define  PMC_CNTRL_SYSCLK_POLARITY	BIT(10) /* sys clk polarity */
>>   #define  PMC_CNTRL_PWRREQ_POLARITY	BIT(8)
>> +#define  PMC_CNTRL_BLINK_EN		BIT(7)
>>   #define  PMC_CNTRL_MAIN_RST		BIT(4)
>>   
>>   #define PMC_WAKE_MASK			0x0c
>>   #define PMC_WAKE_LEVEL			0x10
>>   #define PMC_WAKE_STATUS			0x14
>>   #define PMC_SW_WAKE_STATUS		0x18
>> +#define PMC_DPD_PADS_ORIDE		0x1c
>> +#define  PMC_DPD_PADS_ORIDE_BLINK	BIT(20)
>>   
>>   #define DPD_SAMPLE			0x020
>>   #define  DPD_SAMPLE_ENABLE		BIT(0)
>> @@ -79,6 +82,7 @@
>>   
>>   #define PWRGATE_STATUS			0x38
>>   
>> +#define TEGRA210_PMC_BLINK_TIMER	0x40
>>   #define PMC_IMPL_E_33V_PWR		0x40
>>   
>>   #define PMC_PWR_DET			0x48
>> @@ -247,6 +251,9 @@ static struct pmc_clk_init_data tegra_pmc_clks_data[] = {
>>   	PMC_CLK(3, 22, 18, 0, 0),
>>   };
>>   
>> +static struct pmc_clk_gate blink_override;
>> +static struct pmc_clk_gate blink;
>> +
>>   struct tegra_powergate {
>>   	struct generic_pm_domain genpd;
>>   	struct tegra_pmc *pmc;
>> @@ -359,6 +366,7 @@ struct tegra_pmc_soc {
>>   
>>   	struct pmc_clk_init_data *pmc_clks_data;
>>   	unsigned int num_pmc_clks;
>> +	bool has_blink_output;
>>   };
>>   
>>   static const char * const tegra186_reset_sources[] = {
>> @@ -2530,6 +2538,9 @@ static void tegra_pmc_clock_register(struct tegra_pmc *pmc,
>>   	/* each pmc clock output has a mux and a gate */
>>   	num_clks = pmc->soc->num_pmc_clks * 2;
>>   
>> +	if (pmc->soc->has_blink_output)
>> +		num_clks += 1;
>> +
>>   	if (!num_clks)
>>   		return;
>>   
>> @@ -2604,6 +2615,30 @@ static void tegra_pmc_clock_register(struct tegra_pmc *pmc,
>>   		}
>>   	}
>>   
>> +	if (pmc->soc->has_blink_output) {
>> +		tegra_pmc_writel(pmc, 0x0, TEGRA210_PMC_BLINK_TIMER);
>> +		clkgate = tegra_pmc_clk_gate_register("blink_override",
>> +						      "clk_32k",
>> +						      0, &blink_override,
>> +					      PMC_DPD_PADS_ORIDE,
>> +						      PMC_DPD_PADS_ORIDE_BLINK,
>> +						      NULL);
>> +		if (IS_ERR(clkgate))
>> +			goto free_clks;
>> +
>> +		clkgate = tegra_pmc_clk_gate_register("blink",
>> +						      "blink_override",
>> +						      0, &blink,
>> +						      PMC_CNTRL,
>> +						      PMC_CNTRL_BLINK_EN,
>> +						      NULL);
>> +		if (IS_ERR(clkgate))
>> +			goto free_clks;
>> +
>> +		clk_data->clks[TEGRA_PMC_CLK_BLINK] = clkgate;
>> +		clk_register_clkdev(clkgate, "blink", NULL);
> Tegra20 has pmc->soc->num_pmc_clks = 0 and thus num_clks = 1, while
> TEGRA_PMC_CLK_BLINK = 6.
>
> BTW, Tegra30 doesn't boot. I'll try again v2.
>
> Please fix it all in v2. Compile-test all patches and make at least a
> boot-test where possible.
>
> [snip]

looks like blink output should be enabled during boot for Tegra20 and 
Tegra30 platforms.

Will add init state for blink output in V2. Will compile for old Tegra's 
as well and will try boot-test.