Re: [PATCH v2] thermal: k3_j72xx_bandgap: implement suspend/resume support

["J, KEERTHY" <j-keerthy@ti.com>]

On 1/24/2024 2:26 PM, Thomas Richard wrote:
> Added Keerthy
> 
> On 11/30/23 17:49, Thomas Richard wrote:
>> From: Théo Lebrun <theo.lebrun@bootlin.com>
>>
>> This add suspend-to-ram support.
>>
>> The derived_table is kept-as is, so the resume is only about
>> pm_runtime_* calls and restoring the same registers as the probe.
>>
>> Extract the hardware initialization procedure to a function called at
>> both probe-time & resume-time.
>>
>> The probe-time loop is split in two to ensure doing the hardware
>> initialization before registering thermal zones. That ensures our
>> callbacks cannot be called while in bad state.
Thomas,

Thanks for adding suspend/resume support.

FWIW

Acked-by: Keerthy <j-keerthy@ti.com>

- Keerthy
>>
>> Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
>> Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
>> ---
>>
>> v2:
>> - Fix warnings/errors reported by kernel test robot
>>
>>   drivers/thermal/k3_j72xx_bandgap.c | 112 ++++++++++++++++++++---------
>>   1 file changed, 79 insertions(+), 33 deletions(-)
>>
>> diff --git a/drivers/thermal/k3_j72xx_bandgap.c b/drivers/thermal/k3_j72xx_bandgap.c
>> index c74094a86982..4ad23c8bf73b 100644
>> --- a/drivers/thermal/k3_j72xx_bandgap.c
>> +++ b/drivers/thermal/k3_j72xx_bandgap.c
>> @@ -178,6 +178,7 @@ struct k3_j72xx_bandgap {
>>   	void __iomem *base;
>>   	void __iomem *cfg2_base;
>>   	struct k3_thermal_data *ts_data[K3_VTM_MAX_NUM_TS];
>> +	int cnt;
>>   };
>>   
>>   /* common data structures */
>> @@ -338,24 +339,53 @@ static void print_look_up_table(struct device *dev, int *ref_table)
>>   		dev_dbg(dev, "%d       %d %d\n", i, derived_table[i], ref_table[i]);
>>   }
>>   
>> +static void k3_j72xx_bandgap_init_hw(struct k3_j72xx_bandgap *bgp)
>> +{
>> +	struct k3_thermal_data *data;
>> +	int id, high_max, low_temp;
>> +	u32 val;
>> +
>> +	for (id = 0; id < bgp->cnt; id++) {
>> +		data = bgp->ts_data[id];
>> +		val = readl(bgp->cfg2_base + data->ctrl_offset);
>> +		val |= (K3_VTM_TMPSENS_CTRL_MAXT_OUTRG_EN |
>> +			K3_VTM_TMPSENS_CTRL_SOC |
>> +			K3_VTM_TMPSENS_CTRL_CLRZ | BIT(4));
>> +		writel(val, bgp->cfg2_base + data->ctrl_offset);
>> +	}
>> +
>> +	/*
>> +	 * Program TSHUT thresholds
>> +	 * Step 1: set the thresholds to ~123C and 105C WKUP_VTM_MISC_CTRL2
>> +	 * Step 2: WKUP_VTM_TMPSENS_CTRL_j set the MAXT_OUTRG_EN  bit
>> +	 *         This is already taken care as per of init
>> +	 * Step 3: WKUP_VTM_MISC_CTRL set the ANYMAXT_OUTRG_ALERT_EN  bit
>> +	 */
>> +	high_max = k3_j72xx_bandgap_temp_to_adc_code(MAX_TEMP);
>> +	low_temp = k3_j72xx_bandgap_temp_to_adc_code(COOL_DOWN_TEMP);
>> +
>> +	writel((low_temp << 16) | high_max, bgp->cfg2_base + K3_VTM_MISC_CTRL2_OFFSET);
>> +	mdelay(100);
>> +	writel(K3_VTM_ANYMAXT_OUTRG_ALERT_EN, bgp->cfg2_base + K3_VTM_MISC_CTRL_OFFSET);
>> +}
>> +
>>   struct k3_j72xx_bandgap_data {
>>   	const bool has_errata_i2128;
>>   };
>>   
>>   static int k3_j72xx_bandgap_probe(struct platform_device *pdev)
>>   {
>> -	int ret = 0, cnt, val, id;
>> -	int high_max, low_temp;
>> -	struct resource *res;
>> +	const struct k3_j72xx_bandgap_data *driver_data;
>> +	struct thermal_zone_device *ti_thermal;
>>   	struct device *dev = &pdev->dev;
>> +	bool workaround_needed = false;
>>   	struct k3_j72xx_bandgap *bgp;
>>   	struct k3_thermal_data *data;
>> -	bool workaround_needed = false;
>> -	const struct k3_j72xx_bandgap_data *driver_data;
>> -	struct thermal_zone_device *ti_thermal;
>> -	int *ref_table;
>>   	struct err_values err_vals;
>>   	void __iomem *fuse_base;
>> +	int ret = 0, val, id;
>> +	struct resource *res;
>> +	int *ref_table;
>>   
>>   	const s64 golden_factors[] = {
>>   		-490019999999999936,
>> @@ -422,10 +452,10 @@ static int k3_j72xx_bandgap_probe(struct platform_device *pdev)
>>   
>>   	/* Get the sensor count in the VTM */
>>   	val = readl(bgp->base + K3_VTM_DEVINFO_PWR0_OFFSET);
>> -	cnt = val & K3_VTM_DEVINFO_PWR0_TEMPSENS_CT_MASK;
>> -	cnt >>= __ffs(K3_VTM_DEVINFO_PWR0_TEMPSENS_CT_MASK);
>> +	bgp->cnt = val & K3_VTM_DEVINFO_PWR0_TEMPSENS_CT_MASK;
>> +	bgp->cnt >>= __ffs(K3_VTM_DEVINFO_PWR0_TEMPSENS_CT_MASK);
>>   
>> -	data = devm_kcalloc(bgp->dev, cnt, sizeof(*data), GFP_KERNEL);
>> +	data = devm_kcalloc(bgp->dev, bgp->cnt, sizeof(*data), GFP_KERNEL);
>>   	if (!data) {
>>   		ret = -ENOMEM;
>>   		goto err_alloc;
>> @@ -449,8 +479,8 @@ static int k3_j72xx_bandgap_probe(struct platform_device *pdev)
>>   	else
>>   		init_table(3, ref_table, pvt_wa_factors);
>>   
>> -	/* Register the thermal sensors */
>> -	for (id = 0; id < cnt; id++) {
>> +	/* Precompute the derived table & fill each thermal sensor struct */
>> +	for (id = 0; id < bgp->cnt; id++) {
>>   		data[id].bgp = bgp;
>>   		data[id].ctrl_offset = K3_VTM_TMPSENS0_CTRL_OFFSET + id * 0x20;
>>   		data[id].stat_offset = data[id].ctrl_offset +
>> @@ -470,13 +500,13 @@ static int k3_j72xx_bandgap_probe(struct platform_device *pdev)
>>   		else if (id == 0 && !workaround_needed)
>>   			memcpy(derived_table, ref_table, TABLE_SIZE * 4);
>>   
>> -		val = readl(data[id].bgp->cfg2_base + data[id].ctrl_offset);
>> -		val |= (K3_VTM_TMPSENS_CTRL_MAXT_OUTRG_EN |
>> -			K3_VTM_TMPSENS_CTRL_SOC |
>> -			K3_VTM_TMPSENS_CTRL_CLRZ | BIT(4));
>> -		writel(val, data[id].bgp->cfg2_base + data[id].ctrl_offset);
>> -
>>   		bgp->ts_data[id] = &data[id];
>> +	}
>> +
>> +	k3_j72xx_bandgap_init_hw(bgp);
>> +
>> +	/* Register the thermal sensors */
>> +	for (id = 0; id < bgp->cnt; id++) {
>>   		ti_thermal = devm_thermal_of_zone_register(bgp->dev, id, &data[id],
>>   							   &k3_of_thermal_ops);
>>   		if (IS_ERR(ti_thermal)) {
>> @@ -486,21 +516,7 @@ static int k3_j72xx_bandgap_probe(struct platform_device *pdev)
>>   		}
>>   	}
>>   
>> -	/*
>> -	 * Program TSHUT thresholds
>> -	 * Step 1: set the thresholds to ~123C and 105C WKUP_VTM_MISC_CTRL2
>> -	 * Step 2: WKUP_VTM_TMPSENS_CTRL_j set the MAXT_OUTRG_EN  bit
>> -	 *         This is already taken care as per of init
>> -	 * Step 3: WKUP_VTM_MISC_CTRL set the ANYMAXT_OUTRG_ALERT_EN  bit
>> -	 */
>> -	high_max = k3_j72xx_bandgap_temp_to_adc_code(MAX_TEMP);
>> -	low_temp = k3_j72xx_bandgap_temp_to_adc_code(COOL_DOWN_TEMP);
>> -
>> -	writel((low_temp << 16) | high_max, data[0].bgp->cfg2_base +
>> -	       K3_VTM_MISC_CTRL2_OFFSET);
>> -	mdelay(100);
>> -	writel(K3_VTM_ANYMAXT_OUTRG_ALERT_EN, data[0].bgp->cfg2_base +
>> -	       K3_VTM_MISC_CTRL_OFFSET);
>> +	platform_set_drvdata(pdev, bgp);
>>   
>>   	print_look_up_table(dev, ref_table);
>>   	/*
>> @@ -527,6 +543,35 @@ static void k3_j72xx_bandgap_remove(struct platform_device *pdev)
>>   	pm_runtime_disable(&pdev->dev);
>>   }
>>   
>> +static int __maybe_unused k3_j72xx_bandgap_suspend(struct device *dev)
>> +{
>> +	pm_runtime_put_sync(dev);
>> +	pm_runtime_disable(dev);
>> +	return 0;
>> +}
>> +
>> +static int __maybe_unused k3_j72xx_bandgap_resume(struct device *dev)
>> +{
>> +	struct k3_j72xx_bandgap *bgp = dev_get_drvdata(dev);
>> +	int ret;
>> +
>> +	pm_runtime_enable(dev);
>> +	ret = pm_runtime_get_sync(dev);
>> +	if (ret < 0) {
>> +		pm_runtime_put_noidle(dev);
>> +		pm_runtime_disable(dev);
>> +		return ret;
>> +	}
>> +
>> +	k3_j72xx_bandgap_init_hw(bgp);
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct dev_pm_ops k3_j72xx_bandgap_pm_ops = {
>> +	SET_SYSTEM_SLEEP_PM_OPS(k3_j72xx_bandgap_suspend, k3_j72xx_bandgap_resume)
>> +};
>> +
>>   static const struct k3_j72xx_bandgap_data k3_j72xx_bandgap_j721e_data = {
>>   	.has_errata_i2128 = true,
>>   };
>> @@ -554,6 +599,7 @@ static struct platform_driver k3_j72xx_bandgap_sensor_driver = {
>>   	.driver = {
>>   		.name = "k3-j72xx-soc-thermal",
>>   		.of_match_table	= of_k3_j72xx_bandgap_match,
>> +		.pm = &k3_j72xx_bandgap_pm_ops,
>>   	},
>>   };
>>