diff mbox series

[v6,4/4] thermal: k3_j72xx_bandgap: Add the bandgap driver support

Message ID 20220427064635.24898-5-j-keerthy@ti.com
State Superseded
Headers show
Series thermal: k3_j72xx_bandgap: Add the bandgap driver support | expand

Commit Message

J, KEERTHY April 27, 2022, 6:46 a.m. UTC
Add VTM thermal support. In the Voltage Thermal Management
Module(VTM), K3 J72XX supplies a voltage reference and a temperature
sensor feature that are gathered in the band gap voltage and
temperature sensor (VBGAPTS) module. The band gap provides current and
voltage reference for its internal circuits and other analog IP
blocks. The analog-to-digital converter (ADC) produces an output value
that is proportional to the silicon temperature.

Currently reading temperatures only is supported.  There are no
active/passive cooling agent supported.

J721e SoCs have errata i2128: https://www.ti.com/lit/pdf/sprz455

The VTM Temperature Monitors (TEMPSENSORs) are trimmed during production,
with the resulting values stored in software-readable registers. Software
should use these  register values when translating the Temperature
Monitor output codes to temperature values.

It has an involved workaround. Software needs to read the error codes for
-40C, 30C, 125C from the efuse for each device & derive a new look up table
for adc to temperature conversion. Involved calculating slopes & constants
using 3 different straight line equations with adc refernce codes as the
y-axis & error codes in the x-axis.

-40C to 30C
30C to 125C
125C to 150C

With the above 2 line equations we derive the full look-up table to
workaround the errata i2128 for j721e SoC.

Tested temperature reading on J721e SoC & J7200 SoC.

[daniel.lezcano@linaro.org: Generate look-up tables run-time]
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Keerthy <j-keerthy@ti.com>
---
 drivers/thermal/Makefile           |   2 +-
 drivers/thermal/k3_j72xx_bandgap.c | 566 +++++++++++++++++++++++++++++
 2 files changed, 567 insertions(+), 1 deletion(-)
 create mode 100644 drivers/thermal/k3_j72xx_bandgap.c

Comments

Dan Carpenter May 4, 2022, 8 a.m. UTC | #1
Hi Keerthy,

url:    https://github.com/intel-lab-lkp/linux/commits/Keerthy/thermal-k3_j72xx_bandgap-Add-the-bandgap-driver-support/20220427-144949
base:   https://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git for-next
config: arm-randconfig-m031-20220501 (https://download.01.org/0day-ci/archive/20220503/202205030045.5GxgWkst-lkp@intel.com/config)
compiler: arm-linux-gnueabi-gcc (GCC) 11.3.0

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

smatch warnings:
drivers/thermal/k3_j72xx_bandgap.c:521 k3_j72xx_bandgap_probe() warn: possible memory leak of 'ref_table'

vim +/ref_table +521 drivers/thermal/k3_j72xx_bandgap.c

bb7f95a68cbaa1 Keerthy 2022-04-27  355  static int k3_j72xx_bandgap_probe(struct platform_device *pdev)
bb7f95a68cbaa1 Keerthy 2022-04-27  356  {
bb7f95a68cbaa1 Keerthy 2022-04-27  357  	int ret = 0, cnt, val, id;
bb7f95a68cbaa1 Keerthy 2022-04-27  358  	int high_max, low_temp;
bb7f95a68cbaa1 Keerthy 2022-04-27  359  	struct resource *res;
bb7f95a68cbaa1 Keerthy 2022-04-27  360  	struct device *dev = &pdev->dev;
bb7f95a68cbaa1 Keerthy 2022-04-27  361  	struct k3_j72xx_bandgap *bgp;
bb7f95a68cbaa1 Keerthy 2022-04-27  362  	struct k3_thermal_data *data;
bb7f95a68cbaa1 Keerthy 2022-04-27  363  	int workaround_needed = 0;
bb7f95a68cbaa1 Keerthy 2022-04-27  364  	const struct k3_j72xx_bandgap_data *driver_data;
bb7f95a68cbaa1 Keerthy 2022-04-27  365  	struct thermal_zone_device *ti_thermal;
bb7f95a68cbaa1 Keerthy 2022-04-27  366  	int *ref_table;
bb7f95a68cbaa1 Keerthy 2022-04-27  367  	struct err_values err_vals;
bb7f95a68cbaa1 Keerthy 2022-04-27  368  
bb7f95a68cbaa1 Keerthy 2022-04-27  369  	const s64 golden_factors[] = {
bb7f95a68cbaa1 Keerthy 2022-04-27  370  		-490019999999999936,
bb7f95a68cbaa1 Keerthy 2022-04-27  371  		3251200000000000,
bb7f95a68cbaa1 Keerthy 2022-04-27  372  		-1705800000000,
bb7f95a68cbaa1 Keerthy 2022-04-27  373  		603730000,
bb7f95a68cbaa1 Keerthy 2022-04-27  374  		-92627,
bb7f95a68cbaa1 Keerthy 2022-04-27  375  	};
bb7f95a68cbaa1 Keerthy 2022-04-27  376  
bb7f95a68cbaa1 Keerthy 2022-04-27  377  	const s64 pvt_wa_factors[] = {
bb7f95a68cbaa1 Keerthy 2022-04-27  378  		-415230000000000000,
bb7f95a68cbaa1 Keerthy 2022-04-27  379  		3126600000000000,
bb7f95a68cbaa1 Keerthy 2022-04-27  380  		-1157800000000,
bb7f95a68cbaa1 Keerthy 2022-04-27  381  	};
bb7f95a68cbaa1 Keerthy 2022-04-27  382  
bb7f95a68cbaa1 Keerthy 2022-04-27  383  	bgp = devm_kzalloc(&pdev->dev, sizeof(*bgp), GFP_KERNEL);
bb7f95a68cbaa1 Keerthy 2022-04-27  384  	if (!bgp)
bb7f95a68cbaa1 Keerthy 2022-04-27  385  		return -ENOMEM;
bb7f95a68cbaa1 Keerthy 2022-04-27  386  
bb7f95a68cbaa1 Keerthy 2022-04-27  387  	bgp->dev = dev;
bb7f95a68cbaa1 Keerthy 2022-04-27  388  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
bb7f95a68cbaa1 Keerthy 2022-04-27  389  	bgp->base = devm_ioremap_resource(dev, res);
bb7f95a68cbaa1 Keerthy 2022-04-27  390  	if (IS_ERR(bgp->base))
bb7f95a68cbaa1 Keerthy 2022-04-27  391  		return PTR_ERR(bgp->base);
bb7f95a68cbaa1 Keerthy 2022-04-27  392  
bb7f95a68cbaa1 Keerthy 2022-04-27  393  	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
bb7f95a68cbaa1 Keerthy 2022-04-27  394  	bgp->cfg2_base = devm_ioremap_resource(dev, res);
bb7f95a68cbaa1 Keerthy 2022-04-27  395  	if (IS_ERR(bgp->cfg2_base))
bb7f95a68cbaa1 Keerthy 2022-04-27  396  		return PTR_ERR(bgp->cfg2_base);
bb7f95a68cbaa1 Keerthy 2022-04-27  397  
bb7f95a68cbaa1 Keerthy 2022-04-27  398  	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
bb7f95a68cbaa1 Keerthy 2022-04-27  399  	bgp->fuse_base = devm_ioremap_resource(dev, res);
bb7f95a68cbaa1 Keerthy 2022-04-27  400  	if (IS_ERR(bgp->fuse_base))
bb7f95a68cbaa1 Keerthy 2022-04-27  401  		return PTR_ERR(bgp->fuse_base);
bb7f95a68cbaa1 Keerthy 2022-04-27  402  
bb7f95a68cbaa1 Keerthy 2022-04-27  403  	driver_data = of_device_get_match_data(dev);
bb7f95a68cbaa1 Keerthy 2022-04-27  404  	if (driver_data)
bb7f95a68cbaa1 Keerthy 2022-04-27  405  		workaround_needed = driver_data->has_errata_i2128;
bb7f95a68cbaa1 Keerthy 2022-04-27  406  
bb7f95a68cbaa1 Keerthy 2022-04-27  407  	pm_runtime_enable(dev);
bb7f95a68cbaa1 Keerthy 2022-04-27  408  	ret = pm_runtime_get_sync(dev);
bb7f95a68cbaa1 Keerthy 2022-04-27  409  	if (ret < 0) {
bb7f95a68cbaa1 Keerthy 2022-04-27  410  		pm_runtime_put_noidle(dev);
bb7f95a68cbaa1 Keerthy 2022-04-27  411  		pm_runtime_disable(dev);
bb7f95a68cbaa1 Keerthy 2022-04-27  412  		return ret;
bb7f95a68cbaa1 Keerthy 2022-04-27  413  	}
bb7f95a68cbaa1 Keerthy 2022-04-27  414  
bb7f95a68cbaa1 Keerthy 2022-04-27  415  	/* Get the sensor count in the VTM */
bb7f95a68cbaa1 Keerthy 2022-04-27  416  	val = readl(bgp->base + K3_VTM_DEVINFO_PWR0_OFFSET);
bb7f95a68cbaa1 Keerthy 2022-04-27  417  	cnt = val & K3_VTM_DEVINFO_PWR0_TEMPSENS_CT_MASK;
bb7f95a68cbaa1 Keerthy 2022-04-27  418  	cnt >>= __ffs(K3_VTM_DEVINFO_PWR0_TEMPSENS_CT_MASK);
bb7f95a68cbaa1 Keerthy 2022-04-27  419  
bb7f95a68cbaa1 Keerthy 2022-04-27  420  	data = devm_kcalloc(bgp->dev, cnt, sizeof(*data), GFP_KERNEL);
bb7f95a68cbaa1 Keerthy 2022-04-27  421  	if (!data) {
bb7f95a68cbaa1 Keerthy 2022-04-27  422  		ret = -ENOMEM;
bb7f95a68cbaa1 Keerthy 2022-04-27  423  		goto err_alloc;
bb7f95a68cbaa1 Keerthy 2022-04-27  424  	}
bb7f95a68cbaa1 Keerthy 2022-04-27  425  
bb7f95a68cbaa1 Keerthy 2022-04-27  426  	ref_table = kzalloc(sizeof(*ref_table) * TABLE_SIZE, GFP_KERNEL);
bb7f95a68cbaa1 Keerthy 2022-04-27  427  	if (!ref_table) {
bb7f95a68cbaa1 Keerthy 2022-04-27  428  		ret = -ENOMEM;
bb7f95a68cbaa1 Keerthy 2022-04-27  429  		goto err_alloc;
bb7f95a68cbaa1 Keerthy 2022-04-27  430  	}
bb7f95a68cbaa1 Keerthy 2022-04-27  431  
bb7f95a68cbaa1 Keerthy 2022-04-27  432  	derived_table = devm_kzalloc(bgp->dev, sizeof(*derived_table) * TABLE_SIZE,
bb7f95a68cbaa1 Keerthy 2022-04-27  433  				     GFP_KERNEL);
bb7f95a68cbaa1 Keerthy 2022-04-27  434  	if (!derived_table) {
bb7f95a68cbaa1 Keerthy 2022-04-27  435  		ret = -ENOMEM;
bb7f95a68cbaa1 Keerthy 2022-04-27  436  		goto err_alloc;

ref_table is not freed on error.

bb7f95a68cbaa1 Keerthy 2022-04-27  437  	}
bb7f95a68cbaa1 Keerthy 2022-04-27  438  
bb7f95a68cbaa1 Keerthy 2022-04-27  439  	/* Workaround not needed if bit30/bit31 is set even for J721e */
bb7f95a68cbaa1 Keerthy 2022-04-27  440  	if (workaround_needed && (readl(bgp->fuse_base + 0x0) & 0xc0000000) == 0xc0000000)
bb7f95a68cbaa1 Keerthy 2022-04-27  441  		workaround_needed = false;
bb7f95a68cbaa1 Keerthy 2022-04-27  442  
bb7f95a68cbaa1 Keerthy 2022-04-27  443  	dev_dbg(bgp->dev, "Work around %sneeded\n",
bb7f95a68cbaa1 Keerthy 2022-04-27  444  		workaround_needed ? "not " : "");
bb7f95a68cbaa1 Keerthy 2022-04-27  445  
bb7f95a68cbaa1 Keerthy 2022-04-27  446  	if (!workaround_needed)
bb7f95a68cbaa1 Keerthy 2022-04-27  447  		init_table(5, ref_table, golden_factors);
bb7f95a68cbaa1 Keerthy 2022-04-27  448  	else
bb7f95a68cbaa1 Keerthy 2022-04-27  449  		init_table(3, ref_table, pvt_wa_factors);
bb7f95a68cbaa1 Keerthy 2022-04-27  450  
bb7f95a68cbaa1 Keerthy 2022-04-27  451  	/* Register the thermal sensors */
bb7f95a68cbaa1 Keerthy 2022-04-27  452  	for (id = 0; id < cnt; id++) {
bb7f95a68cbaa1 Keerthy 2022-04-27  453  		data[id].bgp = bgp;
bb7f95a68cbaa1 Keerthy 2022-04-27  454  		data[id].ctrl_offset = K3_VTM_TMPSENS0_CTRL_OFFSET + id * 0x20;
bb7f95a68cbaa1 Keerthy 2022-04-27  455  		data[id].stat_offset = data[id].ctrl_offset +
bb7f95a68cbaa1 Keerthy 2022-04-27  456  					K3_VTM_TMPSENS_STAT_OFFSET;
bb7f95a68cbaa1 Keerthy 2022-04-27  457  
bb7f95a68cbaa1 Keerthy 2022-04-27  458  		if (workaround_needed) {
bb7f95a68cbaa1 Keerthy 2022-04-27  459  			/* ref adc values for -40C, 30C & 125C respectively */
bb7f95a68cbaa1 Keerthy 2022-04-27  460  			err_vals.refs[0] = MINUS40CREF;
bb7f95a68cbaa1 Keerthy 2022-04-27  461  			err_vals.refs[1] = PLUS30CREF;
bb7f95a68cbaa1 Keerthy 2022-04-27  462  			err_vals.refs[2] = PLUS125CREF;
bb7f95a68cbaa1 Keerthy 2022-04-27  463  			err_vals.refs[3] = PLUS150CREF;
bb7f95a68cbaa1 Keerthy 2022-04-27  464  			get_efuse_values(id, &data[id], err_vals.errs, bgp);
bb7f95a68cbaa1 Keerthy 2022-04-27  465  		}
bb7f95a68cbaa1 Keerthy 2022-04-27  466  
bb7f95a68cbaa1 Keerthy 2022-04-27  467  		if (id == 0 && workaround_needed)
bb7f95a68cbaa1 Keerthy 2022-04-27  468  			prep_lookup_table(&err_vals, ref_table);
bb7f95a68cbaa1 Keerthy 2022-04-27  469  		else if (id == 0 && !workaround_needed)
bb7f95a68cbaa1 Keerthy 2022-04-27  470  			memcpy(derived_table, ref_table, TABLE_SIZE * 4);
bb7f95a68cbaa1 Keerthy 2022-04-27  471  
bb7f95a68cbaa1 Keerthy 2022-04-27  472  		val = readl(data[id].bgp->cfg2_base + data[id].ctrl_offset);
bb7f95a68cbaa1 Keerthy 2022-04-27  473  		val |= (K3_VTM_TMPSENS_CTRL_MAXT_OUTRG_EN |
bb7f95a68cbaa1 Keerthy 2022-04-27  474  			K3_VTM_TMPSENS_CTRL_SOC |
bb7f95a68cbaa1 Keerthy 2022-04-27  475  			K3_VTM_TMPSENS_CTRL_CLRZ | BIT(4));
bb7f95a68cbaa1 Keerthy 2022-04-27  476  		writel(val, data[id].bgp->cfg2_base + data[id].ctrl_offset);
bb7f95a68cbaa1 Keerthy 2022-04-27  477  
bb7f95a68cbaa1 Keerthy 2022-04-27  478  		bgp->ts_data[id] = &data[id];
bb7f95a68cbaa1 Keerthy 2022-04-27  479  		ti_thermal =
bb7f95a68cbaa1 Keerthy 2022-04-27  480  		devm_thermal_zone_of_sensor_register(bgp->dev, id,
bb7f95a68cbaa1 Keerthy 2022-04-27  481  						     &data[id],
bb7f95a68cbaa1 Keerthy 2022-04-27  482  						     &k3_of_thermal_ops);
bb7f95a68cbaa1 Keerthy 2022-04-27  483  		if (IS_ERR(ti_thermal)) {
bb7f95a68cbaa1 Keerthy 2022-04-27  484  			dev_err(bgp->dev, "thermal zone device is NULL\n");
bb7f95a68cbaa1 Keerthy 2022-04-27  485  			ret = PTR_ERR(ti_thermal);
bb7f95a68cbaa1 Keerthy 2022-04-27  486  			goto err_alloc;
bb7f95a68cbaa1 Keerthy 2022-04-27  487  		}
bb7f95a68cbaa1 Keerthy 2022-04-27  488  	}
bb7f95a68cbaa1 Keerthy 2022-04-27  489  
bb7f95a68cbaa1 Keerthy 2022-04-27  490  	/*
bb7f95a68cbaa1 Keerthy 2022-04-27  491  	 * Program TSHUT thresholds
bb7f95a68cbaa1 Keerthy 2022-04-27  492  	 * Step 1: set the thresholds to ~123C and 105C WKUP_VTM_MISC_CTRL2
bb7f95a68cbaa1 Keerthy 2022-04-27  493  	 * Step 2: WKUP_VTM_TMPSENS_CTRL_j set the MAXT_OUTRG_EN  bit
bb7f95a68cbaa1 Keerthy 2022-04-27  494  	 *         This is already taken care as per of init
bb7f95a68cbaa1 Keerthy 2022-04-27  495  	 * Step 3: WKUP_VTM_MISC_CTRL set the ANYMAXT_OUTRG_ALERT_EN  bit
bb7f95a68cbaa1 Keerthy 2022-04-27  496  	 */
bb7f95a68cbaa1 Keerthy 2022-04-27  497  	high_max = k3_j72xx_bandgap_temp_to_adc_code(MAX_TEMP);
bb7f95a68cbaa1 Keerthy 2022-04-27  498  	low_temp = k3_j72xx_bandgap_temp_to_adc_code(COOL_DOWN_TEMP);
bb7f95a68cbaa1 Keerthy 2022-04-27  499  
bb7f95a68cbaa1 Keerthy 2022-04-27  500  	writel((low_temp << 16) | high_max, data[0].bgp->cfg2_base +
bb7f95a68cbaa1 Keerthy 2022-04-27  501  	       K3_VTM_MISC_CTRL2_OFFSET);
bb7f95a68cbaa1 Keerthy 2022-04-27  502  	mdelay(100);
bb7f95a68cbaa1 Keerthy 2022-04-27  503  	writel(K3_VTM_ANYMAXT_OUTRG_ALERT_EN, data[0].bgp->cfg2_base +
bb7f95a68cbaa1 Keerthy 2022-04-27  504  	       K3_VTM_MISC_CTRL_OFFSET);
bb7f95a68cbaa1 Keerthy 2022-04-27  505  
bb7f95a68cbaa1 Keerthy 2022-04-27  506  	platform_set_drvdata(pdev, bgp);
bb7f95a68cbaa1 Keerthy 2022-04-27  507  
bb7f95a68cbaa1 Keerthy 2022-04-27  508  	print_look_up_table(dev, ref_table);
bb7f95a68cbaa1 Keerthy 2022-04-27  509  	/*
bb7f95a68cbaa1 Keerthy 2022-04-27  510  	 * Now that the derived_table has the appropriate look up values
bb7f95a68cbaa1 Keerthy 2022-04-27  511  	 * Free up the ref_table
bb7f95a68cbaa1 Keerthy 2022-04-27  512  	 */
bb7f95a68cbaa1 Keerthy 2022-04-27  513  	kfree(ref_table);
bb7f95a68cbaa1 Keerthy 2022-04-27  514  
bb7f95a68cbaa1 Keerthy 2022-04-27  515  	return 0;
bb7f95a68cbaa1 Keerthy 2022-04-27  516  
bb7f95a68cbaa1 Keerthy 2022-04-27  517  err_alloc:
bb7f95a68cbaa1 Keerthy 2022-04-27  518  	pm_runtime_put_sync(&pdev->dev);
bb7f95a68cbaa1 Keerthy 2022-04-27  519  	pm_runtime_disable(&pdev->dev);
bb7f95a68cbaa1 Keerthy 2022-04-27  520  
bb7f95a68cbaa1 Keerthy 2022-04-27 @521  	return ret;
bb7f95a68cbaa1 Keerthy 2022-04-27  522  }
J, KEERTHY May 9, 2022, 3:10 a.m. UTC | #2
On 4/27/2022 12:16 PM, Keerthy wrote:
> Add VTM thermal support. In the Voltage Thermal Management
> Module(VTM), K3 J72XX supplies a voltage reference and a temperature
> sensor feature that are gathered in the band gap voltage and
> temperature sensor (VBGAPTS) module. The band gap provides current and
> voltage reference for its internal circuits and other analog IP
> blocks. The analog-to-digital converter (ADC) produces an output value
> that is proportional to the silicon temperature.
> 
> Currently reading temperatures only is supported.  There are no
> active/passive cooling agent supported.
> 
> J721e SoCs have errata i2128: https://www.ti.com/lit/pdf/sprz455
> 
> The VTM Temperature Monitors (TEMPSENSORs) are trimmed during production,
> with the resulting values stored in software-readable registers. Software
> should use these  register values when translating the Temperature
> Monitor output codes to temperature values.
> 
> It has an involved workaround. Software needs to read the error codes for
> -40C, 30C, 125C from the efuse for each device & derive a new look up table
> for adc to temperature conversion. Involved calculating slopes & constants
> using 3 different straight line equations with adc refernce codes as the
> y-axis & error codes in the x-axis.
> 
> -40C to 30C
> 30C to 125C
> 125C to 150C
> 
> With the above 2 line equations we derive the full look-up table to
> workaround the errata i2128 for j721e SoC.

Hi Daniel,

Any feedback on this series? Let me know.

- Keerthy
> 
> Tested temperature reading on J721e SoC & J7200 SoC.
> 
> [daniel.lezcano@linaro.org: Generate look-up tables run-time]
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Signed-off-by: Keerthy <j-keerthy@ti.com>
> ---
>   drivers/thermal/Makefile           |   2 +-
>   drivers/thermal/k3_j72xx_bandgap.c | 566 +++++++++++++++++++++++++++++
>   2 files changed, 567 insertions(+), 1 deletion(-)
>   create mode 100644 drivers/thermal/k3_j72xx_bandgap.c
> 
> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> index f0c36a1530d5..def8e1a0399c 100644
> --- a/drivers/thermal/Makefile
> +++ b/drivers/thermal/Makefile
> @@ -28,7 +28,7 @@ thermal_sys-$(CONFIG_CPU_IDLE_THERMAL)	+= cpuidle_cooling.o
>   # devfreq cooling
>   thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o
>   
> -obj-$(CONFIG_K3_THERMAL)	+= k3_bandgap.o
> +obj-$(CONFIG_K3_THERMAL)	+= k3_bandgap.o k3_j72xx_bandgap.o
>   # platform thermal drivers
>   obj-y				+= broadcom/
>   obj-$(CONFIG_THERMAL_MMIO)		+= thermal_mmio.o
> diff --git a/drivers/thermal/k3_j72xx_bandgap.c b/drivers/thermal/k3_j72xx_bandgap.c
> new file mode 100644
> index 000000000000..64e323158952
> --- /dev/null
> +++ b/drivers/thermal/k3_j72xx_bandgap.c
> @@ -0,0 +1,566 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * TI Bandgap temperature sensor driver for J72XX SoC Family
> + *
> + * Copyright (C) 2021 Texas Instruments Incorporated - http://www.ti.com/
> + */
> +
> +#include <linux/math.h>
> +#include <linux/math64.h>
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/kernel.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/err.h>
> +#include <linux/types.h>
> +#include <linux/of_platform.h>
> +#include <linux/io.h>
> +#include <linux/thermal.h>
> +#include <linux/of.h>
> +#include <linux/delay.h>
> +#include <linux/slab.h>
> +
> +#define K3_VTM_DEVINFO_PWR0_OFFSET		0x4
> +#define K3_VTM_DEVINFO_PWR0_TEMPSENS_CT_MASK	0xf0
> +#define K3_VTM_TMPSENS0_CTRL_OFFSET		0x300
> +#define K3_VTM_MISC_CTRL_OFFSET			0xc
> +#define K3_VTM_TMPSENS_STAT_OFFSET		0x8
> +#define K3_VTM_ANYMAXT_OUTRG_ALERT_EN		0x1
> +#define K3_VTM_MISC_CTRL2_OFFSET		0x10
> +#define K3_VTM_TS_STAT_DTEMP_MASK		0x3ff
> +#define K3_VTM_MAX_NUM_TS			8
> +#define K3_VTM_TMPSENS_CTRL_SOC			BIT(5)
> +#define K3_VTM_TMPSENS_CTRL_CLRZ		BIT(6)
> +#define K3_VTM_TMPSENS_CTRL_CLKON_REQ		BIT(7)
> +#define K3_VTM_TMPSENS_CTRL_MAXT_OUTRG_EN	BIT(11)
> +
> +#define K3_VTM_CORRECTION_TEMP_CNT		3
> +
> +#define MINUS40CREF				5
> +#define PLUS30CREF				253
> +#define PLUS125CREF				730
> +#define PLUS150CREF				940
> +
> +#define TABLE_SIZE				1024
> +#define MAX_TEMP				123000
> +#define COOL_DOWN_TEMP				105000
> +
> +#define FACTORS_REDUCTION			13
> +static int *derived_table;
> +
> +static int compute_value(int index, const s64 *factors, int nr_factors,
> +			 int reduction)
> +{
> +	s64 value = 0;
> +	int i;
> +
> +	for (i = 0; i < nr_factors; i++)
> +		value += factors[i] * int_pow(index, i);
> +
> +	return (int)div64_s64(value, int_pow(10, reduction));
> +}
> +
> +static void init_table(int factors_size, int *table, const s64 *factors)
> +{
> +	int i;
> +
> +	for (i = 0; i < TABLE_SIZE; i++)
> +		table[i] = compute_value(i, factors, factors_size,
> +					 FACTORS_REDUCTION);
> +}
> +
> +/**
> + * struct err_values - structure containing error/reference values
> + * @refs: reference error values for -40C, 30C, 125C & 150C
> + * @errs: Actual error values for -40C, 30C, 125C & 150C read from the efuse
> + */
> +struct err_values {
> +	int refs[4];
> +	int errs[4];
> +};
> +
> +static void create_table_segments(struct err_values *err_vals, int seg,
> +				  int *ref_table)
> +{
> +	int m = 0, c, num, den, i, err, idx1, idx2, err1, err2, ref1, ref2;
> +
> +	if (seg == 0)
> +		idx1 = 0;
> +	else
> +		idx1 = err_vals->refs[seg];
> +
> +	idx2 = err_vals->refs[seg + 1];
> +	err1 = err_vals->errs[seg];
> +	err2 = err_vals->errs[seg + 1];
> +	ref1 = err_vals->refs[seg];
> +	ref2 = err_vals->refs[seg + 1];
> +
> +	/*
> +	 * Calculate the slope with adc values read from the register
> +	 * as the y-axis param and err in adc value as x-axis param
> +	 */
> +	num = ref2 - ref1;
> +	den = err2 - err1;
> +	if (den)
> +		m = num / den;
> +	c = ref2 - m * err2;
> +
> +	/*
> +	 * Take care of divide by zero error if error values are same
> +	 * Or when the slope is 0
> +	 */
> +	if (den != 0 && m != 0) {
> +		for (i = idx1; i <= idx2; i++) {
> +			err = (i - c) / m;
> +			if (((i + err) < 0) || ((i + err) >= TABLE_SIZE))
> +				continue;
> +			derived_table[i] = ref_table[i + err];
> +		}
> +	} else { /* Constant error take care of divide by zero */
> +		for (i = idx1; i <= idx2; i++) {
> +			if (((i + err1) < 0) || ((i + err1) >= TABLE_SIZE))
> +				continue;
> +			derived_table[i] = ref_table[i + err1];
> +		}
> +	}
> +}
> +
> +static int prep_lookup_table(struct err_values *err_vals, int *ref_table)
> +{
> +	int inc, i, seg;
> +
> +	/*
> +	 * Fill up the lookup table under 3 segments
> +	 * region -40C to +30C
> +	 * region +30C to +125C
> +	 * region +125C to +150C
> +	 */
> +	for (seg = 0; seg < 3; seg++)
> +		create_table_segments(err_vals, seg, ref_table);
> +
> +	/* Get to the first valid temperature */
> +	i = 0;
> +	while (!derived_table[i])
> +		i++;
> +
> +	/*
> +	 * Get to the last zero index and back fill the temperature for
> +	 * sake of continuity
> +	 */
> +	if (i) {
> +		/* 300 milli celsius steps */
> +		while (i--)
> +			derived_table[i] = derived_table[i + 1] - 300;
> +		/* case 0 */
> +		derived_table[i] = derived_table[i + 1] - 300;
> +	}
> +
> +	/*
> +	 * Fill the last trailing 0s which are unfilled with increments of
> +	 * 100 milli celsius till 1023 code
> +	 */
> +	i = TABLE_SIZE - 1;
> +	while (!derived_table[i])
> +		i--;
> +
> +	i++;
> +	inc = 1;
> +	while (i < TABLE_SIZE) {
> +		derived_table[i] = derived_table[i - 1] + inc * 100;
> +		i++;
> +	}
> +
> +	return 0;
> +}
> +
> +struct k3_thermal_data;
> +
> +struct k3_j72xx_bandgap {
> +	struct device *dev;
> +	void __iomem *base;
> +	void __iomem *cfg2_base;
> +	void __iomem *fuse_base;
> +	struct k3_thermal_data *ts_data[K3_VTM_MAX_NUM_TS];
> +};
> +
> +/* common data structures */
> +struct k3_thermal_data {
> +	struct k3_j72xx_bandgap *bgp;
> +	u32 ctrl_offset;
> +	u32 stat_offset;
> +};
> +
> +static int two_cmp(int tmp, int mask)
> +{
> +	tmp = ~(tmp);
> +	tmp &= mask;
> +	tmp += 1;
> +
> +	/* Return negative value */
> +	return (0 - tmp);
> +}
> +
> +static unsigned int vtm_get_best_value(unsigned int s0, unsigned int s1,
> +				       unsigned int s2)
> +{
> +	int d01 = abs(s0 - s1);
> +	int d02 = abs(s0 - s2);
> +	int d12 = abs(s1 - s2);
> +
> +	if (d01 <= d02 && d01 <= d12)
> +		return (s0 + s1) / 2;
> +
> +	if (d02 <= d01 && d02 <= d12)
> +		return (s0 + s2) / 2;
> +
> +	return (s1 + s2) / 2;
> +}
> +
> +static inline int k3_bgp_read_temp(struct k3_thermal_data *devdata,
> +				   int *temp)
> +{
> +	struct k3_j72xx_bandgap *bgp;
> +	unsigned int dtemp, s0, s1, s2;
> +
> +	bgp = devdata->bgp;
> +	/*
> +	 * Errata is applicable for am654 pg 1.0 silicon/J7ES. There
> +	 * is a variation of the order for certain degree centigrade on AM654.
> +	 * Work around that by getting the average of two closest
> +	 * readings out of three readings everytime we want to
> +	 * report temperatures.
> +	 *
> +	 * Errata workaround.
> +	 */
> +	s0 = readl(bgp->base + devdata->stat_offset) &
> +		K3_VTM_TS_STAT_DTEMP_MASK;
> +	s1 = readl(bgp->base + devdata->stat_offset) &
> +		K3_VTM_TS_STAT_DTEMP_MASK;
> +	s2 = readl(bgp->base + devdata->stat_offset) &
> +		K3_VTM_TS_STAT_DTEMP_MASK;
> +	dtemp = vtm_get_best_value(s0, s1, s2);
> +
> +	if (dtemp < 0 || dtemp >= TABLE_SIZE)
> +		return -EINVAL;
> +
> +	*temp = derived_table[dtemp];
> +
> +	return 0;
> +}
> +
> +/* Get temperature callback function for thermal zone */
> +static int k3_thermal_get_temp(void *devdata, int *temp)
> +{
> +	struct k3_thermal_data *data = devdata;
> +	int ret = 0;
> +
> +	ret = k3_bgp_read_temp(data, temp);
> +	if (ret)
> +		return ret;
> +
> +	return ret;
> +}
> +
> +static const struct thermal_zone_of_device_ops k3_of_thermal_ops = {
> +	.get_temp = k3_thermal_get_temp,
> +};
> +
> +static int k3_j72xx_bandgap_temp_to_adc_code(int temp)
> +{
> +	int low = 0, high = TABLE_SIZE - 1, mid;
> +
> +	if (temp > 160000 || temp < -50000)
> +		return -EINVAL;
> +
> +	/* Binary search to find the adc code */
> +	while (low < (high - 1)) {
> +		mid = (low + high) / 2;
> +		if (temp <= derived_table[mid])
> +			high = mid;
> +		else
> +			low = mid;
> +	}
> +
> +	return mid;
> +}
> +
> +static void get_efuse_values(int id, struct k3_thermal_data *data, int *err,
> +			     struct k3_j72xx_bandgap *bgp)
> +{
> +	int i, tmp, pow;
> +	int ct_offsets[5][K3_VTM_CORRECTION_TEMP_CNT] = {
> +		{ 0x0, 0x8, 0x4 },
> +		{ 0x0, 0x8, 0x4 },
> +		{ 0x0, -1,  0x4 },
> +		{ 0x0, 0xC, -1 },
> +		{ 0x0, 0xc, 0x8 }
> +	};
> +	int ct_bm[5][K3_VTM_CORRECTION_TEMP_CNT] = {
> +		{ 0x3f, 0x1fe000, 0x1ff },
> +		{ 0xfc0, 0x1fe000, 0x3fe00 },
> +		{ 0x3f000, 0x7f800000, 0x7fc0000 },
> +		{ 0xfc0000, 0x1fe0, 0x1f800000 },
> +		{ 0x3f000000, 0x1fe000, 0x1ff0 }
> +	};
> +
> +	for (i = 0; i < 3; i++) {
> +		/* Extract the offset value using bit-mask */
> +		if (ct_offsets[id][i] == -1 && i == 1) {
> +			/* 25C offset Case of Sensor 2 split between 2 regs */
> +			tmp = (readl(bgp->fuse_base + 0x8) & 0xE0000000) >> (29);
> +			tmp |= ((readl(bgp->fuse_base + 0xC) & 0x1F) << 3);
> +			pow = tmp & 0x80;
> +		} else if (ct_offsets[id][i] == -1 && i == 2) {
> +			/* 125C Case of Sensor 3 split between 2 regs */
> +			tmp = (readl(bgp->fuse_base + 0x4) & 0xF8000000) >> (27);
> +			tmp |= ((readl(bgp->fuse_base + 0x8) & 0xF) << 5);
> +			pow = tmp & 0x100;
> +		} else {
> +			tmp = readl(bgp->fuse_base + ct_offsets[id][i]);
> +			tmp &= ct_bm[id][i];
> +			tmp = tmp >> __ffs(ct_bm[id][i]);
> +
> +			/* Obtain the sign bit pow*/
> +			pow = ct_bm[id][i] >> __ffs(ct_bm[id][i]);
> +			pow += 1;
> +			pow /= 2;
> +		}
> +
> +		/* Check for negative value */
> +		if (tmp & pow) {
> +			/* 2's complement value */
> +			tmp = two_cmp(tmp, ct_bm[id][i] >> __ffs(ct_bm[id][i]));
> +		}
> +		err[i] = tmp;
> +	}
> +
> +	/* Err value for 150C is set to 0 */
> +	err[i] = 0;
> +}
> +
> +static void print_look_up_table(struct device *dev, int *ref_table)
> +{
> +	int i;
> +
> +	dev_dbg(dev, "The contents of derived array\n");
> +	dev_dbg(dev, "Code   Temperature\n");
> +	for (i = 0; i < TABLE_SIZE; i++)
> +		dev_dbg(dev, "%d       %d %d\n", i, derived_table[i], ref_table[i]);
> +}
> +
> +struct k3_j72xx_bandgap_data {
> +	unsigned int 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;
> +	struct device *dev = &pdev->dev;
> +	struct k3_j72xx_bandgap *bgp;
> +	struct k3_thermal_data *data;
> +	int workaround_needed = 0;
> +	const struct k3_j72xx_bandgap_data *driver_data;
> +	struct thermal_zone_device *ti_thermal;
> +	int *ref_table;
> +	struct err_values err_vals;
> +
> +	const s64 golden_factors[] = {
> +		-490019999999999936,
> +		3251200000000000,
> +		-1705800000000,
> +		603730000,
> +		-92627,
> +	};
> +
> +	const s64 pvt_wa_factors[] = {
> +		-415230000000000000,
> +		3126600000000000,
> +		-1157800000000,
> +	};
> +
> +	bgp = devm_kzalloc(&pdev->dev, sizeof(*bgp), GFP_KERNEL);
> +	if (!bgp)
> +		return -ENOMEM;
> +
> +	bgp->dev = dev;
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	bgp->base = devm_ioremap_resource(dev, res);
> +	if (IS_ERR(bgp->base))
> +		return PTR_ERR(bgp->base);
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> +	bgp->cfg2_base = devm_ioremap_resource(dev, res);
> +	if (IS_ERR(bgp->cfg2_base))
> +		return PTR_ERR(bgp->cfg2_base);
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
> +	bgp->fuse_base = devm_ioremap_resource(dev, res);
> +	if (IS_ERR(bgp->fuse_base))
> +		return PTR_ERR(bgp->fuse_base);
> +
> +	driver_data = of_device_get_match_data(dev);
> +	if (driver_data)
> +		workaround_needed = driver_data->has_errata_i2128;
> +
> +	pm_runtime_enable(dev);
> +	ret = pm_runtime_get_sync(dev);
> +	if (ret < 0) {
> +		pm_runtime_put_noidle(dev);
> +		pm_runtime_disable(dev);
> +		return ret;
> +	}
> +
> +	/* 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);
> +
> +	data = devm_kcalloc(bgp->dev, cnt, sizeof(*data), GFP_KERNEL);
> +	if (!data) {
> +		ret = -ENOMEM;
> +		goto err_alloc;
> +	}
> +
> +	ref_table = kzalloc(sizeof(*ref_table) * TABLE_SIZE, GFP_KERNEL);
> +	if (!ref_table) {
> +		ret = -ENOMEM;
> +		goto err_alloc;
> +	}
> +
> +	derived_table = devm_kzalloc(bgp->dev, sizeof(*derived_table) * TABLE_SIZE,
> +				     GFP_KERNEL);
> +	if (!derived_table) {
> +		ret = -ENOMEM;
> +		goto err_alloc;
> +	}
> +
> +	/* Workaround not needed if bit30/bit31 is set even for J721e */
> +	if (workaround_needed && (readl(bgp->fuse_base + 0x0) & 0xc0000000) == 0xc0000000)
> +		workaround_needed = false;
> +
> +	dev_dbg(bgp->dev, "Work around %sneeded\n",
> +		workaround_needed ? "not " : "");
> +
> +	if (!workaround_needed)
> +		init_table(5, ref_table, golden_factors);
> +	else
> +		init_table(3, ref_table, pvt_wa_factors);
> +
> +	/* Register the thermal sensors */
> +	for (id = 0; id < 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 +
> +					K3_VTM_TMPSENS_STAT_OFFSET;
> +
> +		if (workaround_needed) {
> +			/* ref adc values for -40C, 30C & 125C respectively */
> +			err_vals.refs[0] = MINUS40CREF;
> +			err_vals.refs[1] = PLUS30CREF;
> +			err_vals.refs[2] = PLUS125CREF;
> +			err_vals.refs[3] = PLUS150CREF;
> +			get_efuse_values(id, &data[id], err_vals.errs, bgp);
> +		}
> +
> +		if (id == 0 && workaround_needed)
> +			prep_lookup_table(&err_vals, ref_table);
> +		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];
> +		ti_thermal =
> +		devm_thermal_zone_of_sensor_register(bgp->dev, id,
> +						     &data[id],
> +						     &k3_of_thermal_ops);
> +		if (IS_ERR(ti_thermal)) {
> +			dev_err(bgp->dev, "thermal zone device is NULL\n");
> +			ret = PTR_ERR(ti_thermal);
> +			goto err_alloc;
> +		}
> +	}
> +
> +	/*
> +	 * 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);
> +	/*
> +	 * Now that the derived_table has the appropriate look up values
> +	 * Free up the ref_table
> +	 */
> +	kfree(ref_table);
> +
> +	return 0;
> +
> +err_alloc:
> +	pm_runtime_put_sync(&pdev->dev);
> +	pm_runtime_disable(&pdev->dev);
> +
> +	return ret;
> +}
> +
> +static int k3_j72xx_bandgap_remove(struct platform_device *pdev)
> +{
> +	pm_runtime_put_sync(&pdev->dev);
> +	pm_runtime_disable(&pdev->dev);
> +
> +	return 0;
> +}
> +
> +const struct k3_j72xx_bandgap_data k3_j72xx_bandgap_j721e_data = {
> +	.has_errata_i2128 = 1,
> +};
> +
> +const struct k3_j72xx_bandgap_data k3_j72xx_bandgap_j7200_data = {
> +	.has_errata_i2128 = 0,
> +};
> +
> +static const struct of_device_id of_k3_j72xx_bandgap_match[] = {
> +	{
> +		.compatible = "ti,j721e-vtm",
> +		.data = &k3_j72xx_bandgap_j721e_data,
> +	},
> +	{
> +		.compatible = "ti,j7200-vtm",
> +		.data = &k3_j72xx_bandgap_j7200_data,
> +	},
> +	{ /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, of_k3_j72xx_bandgap_match);
> +
> +static struct platform_driver k3_j72xx_bandgap_sensor_driver = {
> +	.probe = k3_j72xx_bandgap_probe,
> +	.remove = k3_j72xx_bandgap_remove,
> +	.driver = {
> +		.name = "k3-j72xx-soc-thermal",
> +		.of_match_table	= of_k3_j72xx_bandgap_match,
> +	},
> +};
> +
> +module_platform_driver(k3_j72xx_bandgap_sensor_driver);
> +
> +MODULE_DESCRIPTION("K3 bandgap temperature sensor driver");
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("J Keerthy <j-keerthy@ti.com>");
Joe Perches May 9, 2022, 5:20 a.m. UTC | #3
On Wed, 2022-05-04 at 11:00 +0300, Dan Carpenter wrote:
> Hi Keerthy,
[]
> vim +/ref_table +521 drivers/thermal/k3_j72xx_bandgap.c
[]
> bb7f95a68cbaa1 Keerthy 2022-04-27  426  	ref_table = kzalloc(sizeof(*ref_table) * TABLE_SIZE, GFP_KERNEL);
> bb7f95a68cbaa1 Keerthy 2022-04-27  427  	if (!ref_table) {
> bb7f95a68cbaa1 Keerthy 2022-04-27  428  		ret = -ENOMEM;
> bb7f95a68cbaa1 Keerthy 2022-04-27  429  		goto err_alloc;
> bb7f95a68cbaa1 Keerthy 2022-04-27  430  	}

devm_kcalloc

> bb7f95a68cbaa1 Keerthy 2022-04-27  431  
> bb7f95a68cbaa1 Keerthy 2022-04-27  432  	derived_table = devm_kzalloc(bgp->dev, sizeof(*derived_table) * TABLE_SIZE,
> bb7f95a68cbaa1 Keerthy 2022-04-27  433  				     GFP_KERNEL);

here too
Daniel Lezcano May 10, 2022, 3:25 p.m. UTC | #4
On 09/05/2022 05:10, J, KEERTHY wrote:
> 
> 
> On 4/27/2022 12:16 PM, Keerthy wrote:
>> Add VTM thermal support. In the Voltage Thermal Management
>> Module(VTM), K3 J72XX supplies a voltage reference and a temperature
>> sensor feature that are gathered in the band gap voltage and
>> temperature sensor (VBGAPTS) module. The band gap provides current and
>> voltage reference for its internal circuits and other analog IP
>> blocks. The analog-to-digital converter (ADC) produces an output value
>> that is proportional to the silicon temperature.
>>
>> Currently reading temperatures only is supported.  There are no
>> active/passive cooling agent supported.
>>
>> J721e SoCs have errata i2128: https://www.ti.com/lit/pdf/sprz455
>>
>> The VTM Temperature Monitors (TEMPSENSORs) are trimmed during production,
>> with the resulting values stored in software-readable registers. Software
>> should use these  register values when translating the Temperature
>> Monitor output codes to temperature values.
>>
>> It has an involved workaround. Software needs to read the error codes for
>> -40C, 30C, 125C from the efuse for each device & derive a new look up 
>> table
>> for adc to temperature conversion. Involved calculating slopes & 
>> constants
>> using 3 different straight line equations with adc refernce codes as the
>> y-axis & error codes in the x-axis.
>>
>> -40C to 30C
>> 30C to 125C
>> 125C to 150C
>>
>> With the above 2 line equations we derive the full look-up table to
>> workaround the errata i2128 for j721e SoC.
> 
> Hi Daniel,
> 
> Any feedback on this series? Let me know.

There are a few but that would be nit picking and I don't want to 
postpone this driver any longer.

How do you want to proceed? Shall I take it through my tree?
J, KEERTHY May 10, 2022, 5:17 p.m. UTC | #5
On 5/10/2022 8:55 PM, Daniel Lezcano wrote:
> On 09/05/2022 05:10, J, KEERTHY wrote:
>>
>>
>> On 4/27/2022 12:16 PM, Keerthy wrote:
>>> Add VTM thermal support. In the Voltage Thermal Management
>>> Module(VTM), K3 J72XX supplies a voltage reference and a temperature
>>> sensor feature that are gathered in the band gap voltage and
>>> temperature sensor (VBGAPTS) module. The band gap provides current and
>>> voltage reference for its internal circuits and other analog IP
>>> blocks. The analog-to-digital converter (ADC) produces an output value
>>> that is proportional to the silicon temperature.
>>>
>>> Currently reading temperatures only is supported.  There are no
>>> active/passive cooling agent supported.
>>>
>>> J721e SoCs have errata i2128: https://www.ti.com/lit/pdf/sprz455
>>>
>>> The VTM Temperature Monitors (TEMPSENSORs) are trimmed during 
>>> production,
>>> with the resulting values stored in software-readable registers. 
>>> Software
>>> should use these  register values when translating the Temperature
>>> Monitor output codes to temperature values.
>>>
>>> It has an involved workaround. Software needs to read the error codes 
>>> for
>>> -40C, 30C, 125C from the efuse for each device & derive a new look up 
>>> table
>>> for adc to temperature conversion. Involved calculating slopes & 
>>> constants
>>> using 3 different straight line equations with adc refernce codes as the
>>> y-axis & error codes in the x-axis.
>>>
>>> -40C to 30C
>>> 30C to 125C
>>> 125C to 150C
>>>
>>> With the above 2 line equations we derive the full look-up table to
>>> workaround the errata i2128 for j721e SoC.
>>
>> Hi Daniel,
>>
>> Any feedback on this series? Let me know.
> 
> There are a few but that would be nit picking and I don't want to 
> postpone this driver any longer.
> 
> How do you want to proceed? Shall I take it through my tree?

Hi Daniel,

Patch 1 & 4 i.e Documentation patch and driver patch can be picked by 
you. I believe Vignesh will take the dts patches.

Vignesh,

Can you confirm?

- Keerthy

> 
>
Daniel Lezcano May 10, 2022, 5:38 p.m. UTC | #6
On 10/05/2022 19:17, J, KEERTHY wrote:
> 

[ ... ]

> Hi Daniel,
> 
> Patch 1 & 4 i.e Documentation patch and driver patch can be picked by 
> you. I believe Vignesh will take the dts patches.

Will you send a V7 with Krzysztof comments fixed ?
Vignesh Raghavendra May 11, 2022, 4:57 a.m. UTC | #7
On 10/05/22 22:47, J, KEERTHY wrote:
> 
> 
> On 5/10/2022 8:55 PM, Daniel Lezcano wrote:
>> On 09/05/2022 05:10, J, KEERTHY wrote:
>>>
>>>
>>> On 4/27/2022 12:16 PM, Keerthy wrote:
>>>> Add VTM thermal support. In the Voltage Thermal Management
>>>> Module(VTM), K3 J72XX supplies a voltage reference and a temperature
>>>> sensor feature that are gathered in the band gap voltage and
>>>> temperature sensor (VBGAPTS) module. The band gap provides current and
>>>> voltage reference for its internal circuits and other analog IP
>>>> blocks. The analog-to-digital converter (ADC) produces an output value
>>>> that is proportional to the silicon temperature.
>>>>
>>>> Currently reading temperatures only is supported.  There are no
>>>> active/passive cooling agent supported.
>>>>
>>>> J721e SoCs have errata i2128: https://www.ti.com/lit/pdf/sprz455
>>>>
>>>> The VTM Temperature Monitors (TEMPSENSORs) are trimmed during
>>>> production,
>>>> with the resulting values stored in software-readable registers.
>>>> Software
>>>> should use these  register values when translating the Temperature
>>>> Monitor output codes to temperature values.
>>>>
>>>> It has an involved workaround. Software needs to read the error
>>>> codes for
>>>> -40C, 30C, 125C from the efuse for each device & derive a new look
>>>> up table
>>>> for adc to temperature conversion. Involved calculating slopes &
>>>> constants
>>>> using 3 different straight line equations with adc refernce codes as
>>>> the
>>>> y-axis & error codes in the x-axis.
>>>>
>>>> -40C to 30C
>>>> 30C to 125C
>>>> 125C to 150C
>>>>
>>>> With the above 2 line equations we derive the full look-up table to
>>>> workaround the errata i2128 for j721e SoC.
>>>
>>> Hi Daniel,
>>>
>>> Any feedback on this series? Let me know.
>>
>> There are a few but that would be nit picking and I don't want to
>> postpone this driver any longer.
>>
>> How do you want to proceed? Shall I take it through my tree?
> 
> Hi Daniel,
> 
> Patch 1 & 4 i.e Documentation patch and driver patch can be picked by
> you. I believe Vignesh will take the dts patches.
> 
> Vignesh,
> 
> Can you confirm?
> 

Yes, please decouple DT patches from driver+binding patches as they are
to be applied to different trees.
diff mbox series

Patch

diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index f0c36a1530d5..def8e1a0399c 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -28,7 +28,7 @@  thermal_sys-$(CONFIG_CPU_IDLE_THERMAL)	+= cpuidle_cooling.o
 # devfreq cooling
 thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o
 
-obj-$(CONFIG_K3_THERMAL)	+= k3_bandgap.o
+obj-$(CONFIG_K3_THERMAL)	+= k3_bandgap.o k3_j72xx_bandgap.o
 # platform thermal drivers
 obj-y				+= broadcom/
 obj-$(CONFIG_THERMAL_MMIO)		+= thermal_mmio.o
diff --git a/drivers/thermal/k3_j72xx_bandgap.c b/drivers/thermal/k3_j72xx_bandgap.c
new file mode 100644
index 000000000000..64e323158952
--- /dev/null
+++ b/drivers/thermal/k3_j72xx_bandgap.c
@@ -0,0 +1,566 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * TI Bandgap temperature sensor driver for J72XX SoC Family
+ *
+ * Copyright (C) 2021 Texas Instruments Incorporated - http://www.ti.com/
+ */
+
+#include <linux/math.h>
+#include <linux/math64.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/pm_runtime.h>
+#include <linux/err.h>
+#include <linux/types.h>
+#include <linux/of_platform.h>
+#include <linux/io.h>
+#include <linux/thermal.h>
+#include <linux/of.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+
+#define K3_VTM_DEVINFO_PWR0_OFFSET		0x4
+#define K3_VTM_DEVINFO_PWR0_TEMPSENS_CT_MASK	0xf0
+#define K3_VTM_TMPSENS0_CTRL_OFFSET		0x300
+#define K3_VTM_MISC_CTRL_OFFSET			0xc
+#define K3_VTM_TMPSENS_STAT_OFFSET		0x8
+#define K3_VTM_ANYMAXT_OUTRG_ALERT_EN		0x1
+#define K3_VTM_MISC_CTRL2_OFFSET		0x10
+#define K3_VTM_TS_STAT_DTEMP_MASK		0x3ff
+#define K3_VTM_MAX_NUM_TS			8
+#define K3_VTM_TMPSENS_CTRL_SOC			BIT(5)
+#define K3_VTM_TMPSENS_CTRL_CLRZ		BIT(6)
+#define K3_VTM_TMPSENS_CTRL_CLKON_REQ		BIT(7)
+#define K3_VTM_TMPSENS_CTRL_MAXT_OUTRG_EN	BIT(11)
+
+#define K3_VTM_CORRECTION_TEMP_CNT		3
+
+#define MINUS40CREF				5
+#define PLUS30CREF				253
+#define PLUS125CREF				730
+#define PLUS150CREF				940
+
+#define TABLE_SIZE				1024
+#define MAX_TEMP				123000
+#define COOL_DOWN_TEMP				105000
+
+#define FACTORS_REDUCTION			13
+static int *derived_table;
+
+static int compute_value(int index, const s64 *factors, int nr_factors,
+			 int reduction)
+{
+	s64 value = 0;
+	int i;
+
+	for (i = 0; i < nr_factors; i++)
+		value += factors[i] * int_pow(index, i);
+
+	return (int)div64_s64(value, int_pow(10, reduction));
+}
+
+static void init_table(int factors_size, int *table, const s64 *factors)
+{
+	int i;
+
+	for (i = 0; i < TABLE_SIZE; i++)
+		table[i] = compute_value(i, factors, factors_size,
+					 FACTORS_REDUCTION);
+}
+
+/**
+ * struct err_values - structure containing error/reference values
+ * @refs: reference error values for -40C, 30C, 125C & 150C
+ * @errs: Actual error values for -40C, 30C, 125C & 150C read from the efuse
+ */
+struct err_values {
+	int refs[4];
+	int errs[4];
+};
+
+static void create_table_segments(struct err_values *err_vals, int seg,
+				  int *ref_table)
+{
+	int m = 0, c, num, den, i, err, idx1, idx2, err1, err2, ref1, ref2;
+
+	if (seg == 0)
+		idx1 = 0;
+	else
+		idx1 = err_vals->refs[seg];
+
+	idx2 = err_vals->refs[seg + 1];
+	err1 = err_vals->errs[seg];
+	err2 = err_vals->errs[seg + 1];
+	ref1 = err_vals->refs[seg];
+	ref2 = err_vals->refs[seg + 1];
+
+	/*
+	 * Calculate the slope with adc values read from the register
+	 * as the y-axis param and err in adc value as x-axis param
+	 */
+	num = ref2 - ref1;
+	den = err2 - err1;
+	if (den)
+		m = num / den;
+	c = ref2 - m * err2;
+
+	/*
+	 * Take care of divide by zero error if error values are same
+	 * Or when the slope is 0
+	 */
+	if (den != 0 && m != 0) {
+		for (i = idx1; i <= idx2; i++) {
+			err = (i - c) / m;
+			if (((i + err) < 0) || ((i + err) >= TABLE_SIZE))
+				continue;
+			derived_table[i] = ref_table[i + err];
+		}
+	} else { /* Constant error take care of divide by zero */
+		for (i = idx1; i <= idx2; i++) {
+			if (((i + err1) < 0) || ((i + err1) >= TABLE_SIZE))
+				continue;
+			derived_table[i] = ref_table[i + err1];
+		}
+	}
+}
+
+static int prep_lookup_table(struct err_values *err_vals, int *ref_table)
+{
+	int inc, i, seg;
+
+	/*
+	 * Fill up the lookup table under 3 segments
+	 * region -40C to +30C
+	 * region +30C to +125C
+	 * region +125C to +150C
+	 */
+	for (seg = 0; seg < 3; seg++)
+		create_table_segments(err_vals, seg, ref_table);
+
+	/* Get to the first valid temperature */
+	i = 0;
+	while (!derived_table[i])
+		i++;
+
+	/*
+	 * Get to the last zero index and back fill the temperature for
+	 * sake of continuity
+	 */
+	if (i) {
+		/* 300 milli celsius steps */
+		while (i--)
+			derived_table[i] = derived_table[i + 1] - 300;
+		/* case 0 */
+		derived_table[i] = derived_table[i + 1] - 300;
+	}
+
+	/*
+	 * Fill the last trailing 0s which are unfilled with increments of
+	 * 100 milli celsius till 1023 code
+	 */
+	i = TABLE_SIZE - 1;
+	while (!derived_table[i])
+		i--;
+
+	i++;
+	inc = 1;
+	while (i < TABLE_SIZE) {
+		derived_table[i] = derived_table[i - 1] + inc * 100;
+		i++;
+	}
+
+	return 0;
+}
+
+struct k3_thermal_data;
+
+struct k3_j72xx_bandgap {
+	struct device *dev;
+	void __iomem *base;
+	void __iomem *cfg2_base;
+	void __iomem *fuse_base;
+	struct k3_thermal_data *ts_data[K3_VTM_MAX_NUM_TS];
+};
+
+/* common data structures */
+struct k3_thermal_data {
+	struct k3_j72xx_bandgap *bgp;
+	u32 ctrl_offset;
+	u32 stat_offset;
+};
+
+static int two_cmp(int tmp, int mask)
+{
+	tmp = ~(tmp);
+	tmp &= mask;
+	tmp += 1;
+
+	/* Return negative value */
+	return (0 - tmp);
+}
+
+static unsigned int vtm_get_best_value(unsigned int s0, unsigned int s1,
+				       unsigned int s2)
+{
+	int d01 = abs(s0 - s1);
+	int d02 = abs(s0 - s2);
+	int d12 = abs(s1 - s2);
+
+	if (d01 <= d02 && d01 <= d12)
+		return (s0 + s1) / 2;
+
+	if (d02 <= d01 && d02 <= d12)
+		return (s0 + s2) / 2;
+
+	return (s1 + s2) / 2;
+}
+
+static inline int k3_bgp_read_temp(struct k3_thermal_data *devdata,
+				   int *temp)
+{
+	struct k3_j72xx_bandgap *bgp;
+	unsigned int dtemp, s0, s1, s2;
+
+	bgp = devdata->bgp;
+	/*
+	 * Errata is applicable for am654 pg 1.0 silicon/J7ES. There
+	 * is a variation of the order for certain degree centigrade on AM654.
+	 * Work around that by getting the average of two closest
+	 * readings out of three readings everytime we want to
+	 * report temperatures.
+	 *
+	 * Errata workaround.
+	 */
+	s0 = readl(bgp->base + devdata->stat_offset) &
+		K3_VTM_TS_STAT_DTEMP_MASK;
+	s1 = readl(bgp->base + devdata->stat_offset) &
+		K3_VTM_TS_STAT_DTEMP_MASK;
+	s2 = readl(bgp->base + devdata->stat_offset) &
+		K3_VTM_TS_STAT_DTEMP_MASK;
+	dtemp = vtm_get_best_value(s0, s1, s2);
+
+	if (dtemp < 0 || dtemp >= TABLE_SIZE)
+		return -EINVAL;
+
+	*temp = derived_table[dtemp];
+
+	return 0;
+}
+
+/* Get temperature callback function for thermal zone */
+static int k3_thermal_get_temp(void *devdata, int *temp)
+{
+	struct k3_thermal_data *data = devdata;
+	int ret = 0;
+
+	ret = k3_bgp_read_temp(data, temp);
+	if (ret)
+		return ret;
+
+	return ret;
+}
+
+static const struct thermal_zone_of_device_ops k3_of_thermal_ops = {
+	.get_temp = k3_thermal_get_temp,
+};
+
+static int k3_j72xx_bandgap_temp_to_adc_code(int temp)
+{
+	int low = 0, high = TABLE_SIZE - 1, mid;
+
+	if (temp > 160000 || temp < -50000)
+		return -EINVAL;
+
+	/* Binary search to find the adc code */
+	while (low < (high - 1)) {
+		mid = (low + high) / 2;
+		if (temp <= derived_table[mid])
+			high = mid;
+		else
+			low = mid;
+	}
+
+	return mid;
+}
+
+static void get_efuse_values(int id, struct k3_thermal_data *data, int *err,
+			     struct k3_j72xx_bandgap *bgp)
+{
+	int i, tmp, pow;
+	int ct_offsets[5][K3_VTM_CORRECTION_TEMP_CNT] = {
+		{ 0x0, 0x8, 0x4 },
+		{ 0x0, 0x8, 0x4 },
+		{ 0x0, -1,  0x4 },
+		{ 0x0, 0xC, -1 },
+		{ 0x0, 0xc, 0x8 }
+	};
+	int ct_bm[5][K3_VTM_CORRECTION_TEMP_CNT] = {
+		{ 0x3f, 0x1fe000, 0x1ff },
+		{ 0xfc0, 0x1fe000, 0x3fe00 },
+		{ 0x3f000, 0x7f800000, 0x7fc0000 },
+		{ 0xfc0000, 0x1fe0, 0x1f800000 },
+		{ 0x3f000000, 0x1fe000, 0x1ff0 }
+	};
+
+	for (i = 0; i < 3; i++) {
+		/* Extract the offset value using bit-mask */
+		if (ct_offsets[id][i] == -1 && i == 1) {
+			/* 25C offset Case of Sensor 2 split between 2 regs */
+			tmp = (readl(bgp->fuse_base + 0x8) & 0xE0000000) >> (29);
+			tmp |= ((readl(bgp->fuse_base + 0xC) & 0x1F) << 3);
+			pow = tmp & 0x80;
+		} else if (ct_offsets[id][i] == -1 && i == 2) {
+			/* 125C Case of Sensor 3 split between 2 regs */
+			tmp = (readl(bgp->fuse_base + 0x4) & 0xF8000000) >> (27);
+			tmp |= ((readl(bgp->fuse_base + 0x8) & 0xF) << 5);
+			pow = tmp & 0x100;
+		} else {
+			tmp = readl(bgp->fuse_base + ct_offsets[id][i]);
+			tmp &= ct_bm[id][i];
+			tmp = tmp >> __ffs(ct_bm[id][i]);
+
+			/* Obtain the sign bit pow*/
+			pow = ct_bm[id][i] >> __ffs(ct_bm[id][i]);
+			pow += 1;
+			pow /= 2;
+		}
+
+		/* Check for negative value */
+		if (tmp & pow) {
+			/* 2's complement value */
+			tmp = two_cmp(tmp, ct_bm[id][i] >> __ffs(ct_bm[id][i]));
+		}
+		err[i] = tmp;
+	}
+
+	/* Err value for 150C is set to 0 */
+	err[i] = 0;
+}
+
+static void print_look_up_table(struct device *dev, int *ref_table)
+{
+	int i;
+
+	dev_dbg(dev, "The contents of derived array\n");
+	dev_dbg(dev, "Code   Temperature\n");
+	for (i = 0; i < TABLE_SIZE; i++)
+		dev_dbg(dev, "%d       %d %d\n", i, derived_table[i], ref_table[i]);
+}
+
+struct k3_j72xx_bandgap_data {
+	unsigned int 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;
+	struct device *dev = &pdev->dev;
+	struct k3_j72xx_bandgap *bgp;
+	struct k3_thermal_data *data;
+	int workaround_needed = 0;
+	const struct k3_j72xx_bandgap_data *driver_data;
+	struct thermal_zone_device *ti_thermal;
+	int *ref_table;
+	struct err_values err_vals;
+
+	const s64 golden_factors[] = {
+		-490019999999999936,
+		3251200000000000,
+		-1705800000000,
+		603730000,
+		-92627,
+	};
+
+	const s64 pvt_wa_factors[] = {
+		-415230000000000000,
+		3126600000000000,
+		-1157800000000,
+	};
+
+	bgp = devm_kzalloc(&pdev->dev, sizeof(*bgp), GFP_KERNEL);
+	if (!bgp)
+		return -ENOMEM;
+
+	bgp->dev = dev;
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	bgp->base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(bgp->base))
+		return PTR_ERR(bgp->base);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	bgp->cfg2_base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(bgp->cfg2_base))
+		return PTR_ERR(bgp->cfg2_base);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
+	bgp->fuse_base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(bgp->fuse_base))
+		return PTR_ERR(bgp->fuse_base);
+
+	driver_data = of_device_get_match_data(dev);
+	if (driver_data)
+		workaround_needed = driver_data->has_errata_i2128;
+
+	pm_runtime_enable(dev);
+	ret = pm_runtime_get_sync(dev);
+	if (ret < 0) {
+		pm_runtime_put_noidle(dev);
+		pm_runtime_disable(dev);
+		return ret;
+	}
+
+	/* 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);
+
+	data = devm_kcalloc(bgp->dev, cnt, sizeof(*data), GFP_KERNEL);
+	if (!data) {
+		ret = -ENOMEM;
+		goto err_alloc;
+	}
+
+	ref_table = kzalloc(sizeof(*ref_table) * TABLE_SIZE, GFP_KERNEL);
+	if (!ref_table) {
+		ret = -ENOMEM;
+		goto err_alloc;
+	}
+
+	derived_table = devm_kzalloc(bgp->dev, sizeof(*derived_table) * TABLE_SIZE,
+				     GFP_KERNEL);
+	if (!derived_table) {
+		ret = -ENOMEM;
+		goto err_alloc;
+	}
+
+	/* Workaround not needed if bit30/bit31 is set even for J721e */
+	if (workaround_needed && (readl(bgp->fuse_base + 0x0) & 0xc0000000) == 0xc0000000)
+		workaround_needed = false;
+
+	dev_dbg(bgp->dev, "Work around %sneeded\n",
+		workaround_needed ? "not " : "");
+
+	if (!workaround_needed)
+		init_table(5, ref_table, golden_factors);
+	else
+		init_table(3, ref_table, pvt_wa_factors);
+
+	/* Register the thermal sensors */
+	for (id = 0; id < 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 +
+					K3_VTM_TMPSENS_STAT_OFFSET;
+
+		if (workaround_needed) {
+			/* ref adc values for -40C, 30C & 125C respectively */
+			err_vals.refs[0] = MINUS40CREF;
+			err_vals.refs[1] = PLUS30CREF;
+			err_vals.refs[2] = PLUS125CREF;
+			err_vals.refs[3] = PLUS150CREF;
+			get_efuse_values(id, &data[id], err_vals.errs, bgp);
+		}
+
+		if (id == 0 && workaround_needed)
+			prep_lookup_table(&err_vals, ref_table);
+		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];
+		ti_thermal =
+		devm_thermal_zone_of_sensor_register(bgp->dev, id,
+						     &data[id],
+						     &k3_of_thermal_ops);
+		if (IS_ERR(ti_thermal)) {
+			dev_err(bgp->dev, "thermal zone device is NULL\n");
+			ret = PTR_ERR(ti_thermal);
+			goto err_alloc;
+		}
+	}
+
+	/*
+	 * 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);
+	/*
+	 * Now that the derived_table has the appropriate look up values
+	 * Free up the ref_table
+	 */
+	kfree(ref_table);
+
+	return 0;
+
+err_alloc:
+	pm_runtime_put_sync(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+
+	return ret;
+}
+
+static int k3_j72xx_bandgap_remove(struct platform_device *pdev)
+{
+	pm_runtime_put_sync(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+
+	return 0;
+}
+
+const struct k3_j72xx_bandgap_data k3_j72xx_bandgap_j721e_data = {
+	.has_errata_i2128 = 1,
+};
+
+const struct k3_j72xx_bandgap_data k3_j72xx_bandgap_j7200_data = {
+	.has_errata_i2128 = 0,
+};
+
+static const struct of_device_id of_k3_j72xx_bandgap_match[] = {
+	{
+		.compatible = "ti,j721e-vtm",
+		.data = &k3_j72xx_bandgap_j721e_data,
+	},
+	{
+		.compatible = "ti,j7200-vtm",
+		.data = &k3_j72xx_bandgap_j7200_data,
+	},
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, of_k3_j72xx_bandgap_match);
+
+static struct platform_driver k3_j72xx_bandgap_sensor_driver = {
+	.probe = k3_j72xx_bandgap_probe,
+	.remove = k3_j72xx_bandgap_remove,
+	.driver = {
+		.name = "k3-j72xx-soc-thermal",
+		.of_match_table	= of_k3_j72xx_bandgap_match,
+	},
+};
+
+module_platform_driver(k3_j72xx_bandgap_sensor_driver);
+
+MODULE_DESCRIPTION("K3 bandgap temperature sensor driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("J Keerthy <j-keerthy@ti.com>");