thermal: ti-bandgap: Add support for temperature sensor

The dra7xx series of SOCs contain a temperature sensor and an
associated analog-to-digital converter (ADC) which produces
an output which is proportional to the SOC temperature.
Add support for this temperature sensor.

Signed-off-by: Faiz Abbas <faiz_abbas@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
This commit is contained in:
Faiz Abbas 2017-11-14 16:12:31 +05:30 committed by Tom Rini
parent 5ad1fec6ed
commit 8502f9f6d7
6 changed files with 249 additions and 0 deletions

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@ -605,6 +605,14 @@ config SPL_SPI_SUPPORT
enable SPI drivers that are needed for other purposes also, such
as a SPI PMIC.
config SPL_THERMAL
bool "Driver support for thermal devices"
help
Enable support for temperature-sensing devices. Some SoCs have on-chip
temperature sensors to permit warnings, speed throttling or even
automatic power-off when the temperature gets too high or low. Other
devices may be discrete but connected on a suitable bus.
config SPL_USB_HOST_SUPPORT
bool "Support USB host drivers"
help

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@ -0,0 +1,35 @@
* Texas Instrument dra7xx SCM bandgap bindings
In the System Control Module, SoC 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.
Required properties:
- compatible : Should be:
- "ti,dra752-bandgap"
- interrupts : this entry should indicate which interrupt line
the talert signal is routed to;
- regs : this is specific to each bandgap version, because
the mapping may change from soc to soc, apart from depending
on available features.
Optional:
- gpios : this entry should be used to inform which GPIO
line the tshut signal is routed to. The informed GPIO will
be treated as an IRQ;
Example:
bandgap {
reg = <0x4a0021e0 0xc
0x4a00232c 0xc
0x4a002380 0x2c
0x4a0023C0 0x3c
0x4a002564 0x8
0x4a002574 0x50>;
compatible = "ti,dra752-bandgap";
interrupts = <0 126 4>; /* talert */
};

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@ -50,6 +50,7 @@ obj-$(CONFIG_SPL_SATA_SUPPORT) += ata/ scsi/
obj-$(CONFIG_SPL_USB_HOST_SUPPORT) += block/
obj-$(CONFIG_SPL_MMC_SUPPORT) += block/
obj-$(CONFIG_SPL_FPGA_SUPPORT) += fpga/
obj-$(CONFIG_SPL_THERMAL) += thermal/
endif
endif

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@ -17,4 +17,10 @@ config IMX_THERMAL
cpufreq is used as the cooling device to throttle CPUs when the
passive trip is crossed.
config TI_DRA7_THERMAL
bool "Temperature sensor driver for TI dra7xx SOCs"
help
Enable thermal support for for the Texas Instruments DRA752 SoC family.
The driver supports reading CPU temperature.
endif # if DM_THERMAL

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@ -7,3 +7,4 @@
obj-$(CONFIG_DM_THERMAL) += thermal-uclass.o
obj-$(CONFIG_IMX_THERMAL) += imx_thermal.o
obj-$(CONFIG_TI_DRA7_THERMAL) += ti-bandgap.o

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@ -0,0 +1,198 @@
/*
* TI Bandgap temperature sensor driver
*
* Copyright (C) 2017 Texas Instruments Incorporated - http://www.ti.com/
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation version 2.
*
* This program is distributed "as is" WITHOUT ANY WARRANTY of any
* kind, whether express or implied; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* Taken from Linux v4.9 (drivers/thermal/ti-soc-thermal/ti-bandgap.c)
* and ported to uboot.
*
*/
#include <asm/io.h>
#include <dm.h>
#include <thermal.h>
#define CTRL_CORE_TEMP_SENSOR_MPU 0
#define DRA752_ADC_START_VALUE 540
struct ti_bandgap {
ulong base;
int temperature; /* in mili degree celsius */
};
/*
* DRA752 : Temperature values in milli degree celsius
* ADC code values from 540 to 945
*/
static int dra752_adc_to_temp[] = {
/* Index 540 - 549 */
-40000, -40000, -40000, -40000, -39800, -39400, -39000, -38600, -38200,
-37800,
/* Index 550 - 559 */
-37400, -37000, -36600, -36200, -35800, -35300, -34700, -34200, -33800,
-33400,
/* Index 560 - 569 */
-33000, -32600, -32200, -31800, -31400, -31000, -30600, -30200, -29800,
-29400,
/* Index 570 - 579 */
-29000, -28600, -28200, -27700, -27100, -26600, -26200, -25800, -25400,
-25000,
/* Index 580 - 589 */
-24600, -24200, -23800, -23400, -23000, -22600, -22200, -21800, -21400,
-21000,
/* Index 590 - 599 */
-20500, -19900, -19400, -19000, -18600, -18200, -17800, -17400, -17000,
-16600,
/* Index 600 - 609 */
-16200, -15800, -15400, -15000, -14600, -14200, -13800, -13400, -13000,
-12500,
/* Index 610 - 619 */
-11900, -11400, -11000, -10600, -10200, -9800, -9400, -9000, -8600,
-8200,
/* Index 620 - 629 */
-7800, -7400, -7000, -6600, -6200, -5800, -5400, -5000, -4500,
-3900,
/* Index 630 - 639 */
-3400, -3000, -2600, -2200, -1800, -1400, -1000, -600, -200,
200,
/* Index 640 - 649 */
600, 1000, 1400, 1800, 2200, 2600, 3000, 3400, 3900,
4500,
/* Index 650 - 659 */
5000, 5400, 5800, 6200, 6600, 7000, 7400, 7800, 8200,
8600,
/* Index 660 - 669 */
9000, 9400, 9800, 10200, 10600, 11000, 11400, 11800, 12200,
12700,
/* Index 670 - 679 */
13300, 13800, 14200, 14600, 15000, 15400, 15800, 16200, 16600,
17000,
/* Index 680 - 689 */
17400, 17800, 18200, 18600, 19000, 19400, 19800, 20200, 20600,
21000,
/* Index 690 - 699 */
21400, 21900, 22500, 23000, 23400, 23800, 24200, 24600, 25000,
25400,
/* Index 700 - 709 */
25800, 26200, 26600, 27000, 27400, 27800, 28200, 28600, 29000,
29400,
/* Index 710 - 719 */
29800, 30200, 30600, 31000, 31400, 31900, 32500, 33000, 33400,
33800,
/* Index 720 - 729 */
34200, 34600, 35000, 35400, 35800, 36200, 36600, 37000, 37400,
37800,
/* Index 730 - 739 */
38200, 38600, 39000, 39400, 39800, 40200, 40600, 41000, 41400,
41800,
/* Index 740 - 749 */
42200, 42600, 43100, 43700, 44200, 44600, 45000, 45400, 45800,
46200,
/* Index 750 - 759 */
46600, 47000, 47400, 47800, 48200, 48600, 49000, 49400, 49800,
50200,
/* Index 760 - 769 */
50600, 51000, 51400, 51800, 52200, 52600, 53000, 53400, 53800,
54200,
/* Index 770 - 779 */
54600, 55000, 55400, 55900, 56500, 57000, 57400, 57800, 58200,
58600,
/* Index 780 - 789 */
59000, 59400, 59800, 60200, 60600, 61000, 61400, 61800, 62200,
62600,
/* Index 790 - 799 */
63000, 63400, 63800, 64200, 64600, 65000, 65400, 65800, 66200,
66600,
/* Index 800 - 809 */
67000, 67400, 67800, 68200, 68600, 69000, 69400, 69800, 70200,
70600,
/* Index 810 - 819 */
71000, 71500, 72100, 72600, 73000, 73400, 73800, 74200, 74600,
75000,
/* Index 820 - 829 */
75400, 75800, 76200, 76600, 77000, 77400, 77800, 78200, 78600,
79000,
/* Index 830 - 839 */
79400, 79800, 80200, 80600, 81000, 81400, 81800, 82200, 82600,
83000,
/* Index 840 - 849 */
83400, 83800, 84200, 84600, 85000, 85400, 85800, 86200, 86600,
87000,
/* Index 850 - 859 */
87400, 87800, 88200, 88600, 89000, 89400, 89800, 90200, 90600,
91000,
/* Index 860 - 869 */
91400, 91800, 92200, 92600, 93000, 93400, 93800, 94200, 94600,
95000,
/* Index 870 - 879 */
95400, 95800, 96200, 96600, 97000, 97500, 98100, 98600, 99000,
99400,
/* Index 880 - 889 */
99800, 100200, 100600, 101000, 101400, 101800, 102200, 102600, 103000,
103400,
/* Index 890 - 899 */
103800, 104200, 104600, 105000, 105400, 105800, 106200, 106600, 107000,
107400,
/* Index 900 - 909 */
107800, 108200, 108600, 109000, 109400, 109800, 110200, 110600, 111000,
111400,
/* Index 910 - 919 */
111800, 112200, 112600, 113000, 113400, 113800, 114200, 114600, 115000,
115400,
/* Index 920 - 929 */
115800, 116200, 116600, 117000, 117400, 117800, 118200, 118600, 119000,
119400,
/* Index 930 - 939 */
119800, 120200, 120600, 121000, 121400, 121800, 122200, 122600, 123000,
123400,
/* Index 940 - 945 */
123800, 124200, 124600, 124900, 125000, 125000,
};
static int ti_bandgap_get_temp(struct udevice *dev, int *temp)
{
struct ti_bandgap *bgp = dev_get_priv(dev);
bgp->temperature = 0x3ff & readl(bgp->base + CTRL_CORE_TEMP_SENSOR_MPU);
*temp = dra752_adc_to_temp[bgp->temperature - DRA752_ADC_START_VALUE];
return 0;
}
static struct dm_thermal_ops ti_thermal_ops = {
.get_temp = ti_bandgap_get_temp,
};
static int ti_bandgap_probe(struct udevice *dev)
{
struct ti_bandgap *bgp = dev_get_priv(dev);
bgp->base = devfdt_get_addr_index(dev, 1);
return 0;
}
static const struct udevice_id of_ti_bandgap_match[] = {
{
.compatible = "ti,dra752-bandgap",
},
{},
};
U_BOOT_DRIVER(ti_bandgap_thermal) = {
.name = "ti_bandgap_thermal",
.id = UCLASS_THERMAL,
.ops = &ti_thermal_ops,
.probe = ti_bandgap_probe,
.of_match = of_ti_bandgap_match,
.priv_auto_alloc_size = sizeof(struct ti_bandgap),
};