--- /dev/null
+From f8b54d1120b81ed57bed96cc8e814ba08886d1e5 Mon Sep 17 00:00:00 2001
+From: Andre Przywara <andre.przywara@arm.com>
+Date: Mon, 19 Feb 2024 15:36:37 +0000
+Subject: [PATCH] thermal/drivers/sun8i: Add SRAM register access code
+
+The Allwinner H616 SoC needs to clear a bit in one register in the SRAM
+controller, to report reasonable temperature values. On reset, bit 16 in
+register 0x3000000 is set, which leads to the driver reporting
+temperatures around 200C. Clearing this bit brings the values down to the
+expected range. The BSP code does a one-time write in U-Boot, with a
+comment just mentioning the effect on the THS, but offering no further
+explanation.
+
+To not rely on firmware to set things up for us, add code that queries
+the SRAM controller device via a DT phandle link, then clear just this
+single bit.
+
+Signed-off-by: Andre Przywara <andre.przywara@arm.com>
+Acked-by: Vasily Khoruzhick <anarsoul@gmail.com>
+Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
+Link: https://lore.kernel.org/r/20240219153639.179814-6-andre.przywara@arm.com
+---
+ drivers/thermal/sun8i_thermal.c | 51 +++++++++++++++++++++++++++++++++
+ 1 file changed, 51 insertions(+)
+
+--- a/drivers/thermal/sun8i_thermal.c
++++ b/drivers/thermal/sun8i_thermal.c
+@@ -15,6 +15,7 @@
+ #include <linux/module.h>
+ #include <linux/nvmem-consumer.h>
+ #include <linux/of_device.h>
++#include <linux/of_platform.h>
+ #include <linux/platform_device.h>
+ #include <linux/regmap.h>
+ #include <linux/reset.h>
+@@ -68,6 +69,7 @@ struct tsensor {
+ struct ths_thermal_chip {
+ bool has_mod_clk;
+ bool has_bus_clk_reset;
++ bool needs_sram;
+ int sensor_num;
+ int offset;
+ int scale;
+@@ -85,12 +87,16 @@ struct ths_device {
+ const struct ths_thermal_chip *chip;
+ struct device *dev;
+ struct regmap *regmap;
++ struct regmap_field *sram_regmap_field;
+ struct reset_control *reset;
+ struct clk *bus_clk;
+ struct clk *mod_clk;
+ struct tsensor sensor[MAX_SENSOR_NUM];
+ };
+
++/* The H616 needs to have a bit 16 in the SRAM control register cleared. */
++static const struct reg_field sun8i_ths_sram_reg_field = REG_FIELD(0x0, 16, 16);
++
+ /* Temp Unit: millidegree Celsius */
+ static int sun8i_ths_calc_temp(struct ths_device *tmdev,
+ int id, int reg)
+@@ -337,6 +343,34 @@ static void sun8i_ths_reset_control_asse
+ reset_control_assert(data);
+ }
+
++static struct regmap *sun8i_ths_get_sram_regmap(struct device_node *node)
++{
++ struct device_node *sram_node;
++ struct platform_device *sram_pdev;
++ struct regmap *regmap = NULL;
++
++ sram_node = of_parse_phandle(node, "allwinner,sram", 0);
++ if (!sram_node)
++ return ERR_PTR(-ENODEV);
++
++ sram_pdev = of_find_device_by_node(sram_node);
++ if (!sram_pdev) {
++ /* platform device might not be probed yet */
++ regmap = ERR_PTR(-EPROBE_DEFER);
++ goto out_put_node;
++ }
++
++ /* If no regmap is found then the other device driver is at fault */
++ regmap = dev_get_regmap(&sram_pdev->dev, NULL);
++ if (!regmap)
++ regmap = ERR_PTR(-EINVAL);
++
++ platform_device_put(sram_pdev);
++out_put_node:
++ of_node_put(sram_node);
++ return regmap;
++}
++
+ static int sun8i_ths_resource_init(struct ths_device *tmdev)
+ {
+ struct device *dev = tmdev->dev;
+@@ -381,6 +415,19 @@ static int sun8i_ths_resource_init(struc
+ if (ret)
+ return ret;
+
++ if (tmdev->chip->needs_sram) {
++ struct regmap *regmap;
++
++ regmap = sun8i_ths_get_sram_regmap(dev->of_node);
++ if (IS_ERR(regmap))
++ return PTR_ERR(regmap);
++ tmdev->sram_regmap_field = devm_regmap_field_alloc(dev,
++ regmap,
++ sun8i_ths_sram_reg_field);
++ if (IS_ERR(tmdev->sram_regmap_field))
++ return PTR_ERR(tmdev->sram_regmap_field);
++ }
++
+ ret = sun8i_ths_calibrate(tmdev);
+ if (ret)
+ return ret;
+@@ -427,6 +474,10 @@ static int sun50i_h6_thermal_init(struct
+ {
+ int val;
+
++ /* The H616 needs to have a bit in the SRAM control register cleared. */
++ if (tmdev->sram_regmap_field)
++ regmap_field_write(tmdev->sram_regmap_field, 0);
++
+ /*
+ * The manual recommends an overall sample frequency of 50 KHz (20us,
+ * 480 cycles at 24 MHz), which provides plenty of time for both the
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