[PATCH v4 00/10] pmdomain: samsung: add support for Google GS101

[PATCH v4 00/10] pmdomain: samsung: add support for Google GS101

[André Draszik]

Hi,

This series adds support for the power domains on Google GS101.

There are a few differences compared to SoCs already supported by this
driver:
* register access does not work via plain ioremap() / readl() /
  writel().
  Instead, the regmap created by the PMU driver must be used (which
  uses Arm SMCC calls under the hood).
* DTZPC: a call needs to be made before and after power domain off/on,
  to inform the EL3 firmware of the request.
* power domains can and are fed by a regulator rail and therefore
  regulator control needed be implemented.

Bullet points 2 and 3 are new compared to previous versions of this
series, and related changes are in patches 1, 2, 9, and 10. I can merge
patch 9 (SMC call) into the gs101 patch (patch 7) if preferred, but for
now I kept them independent to make it easier to see changes compared
to previous versions of this series, and because patch 8 actually
applies to not only gs101, but to many newer Exynos SoCs, and to make
the two patches themselves easier to review and reason about.

The DT update to add the new required properties on gs101 will be
posted separately.

Signed-off-by: André Draszik <andre.draszik@linaro.org>
---
Changes in v4:
- drop unneeded or already merged patches
- drop patch "pmdomain: samsung: convert to regmap_read_poll_timeout()"
  as Marek reported issues on some platforms
- rebase
- DTZPC related changes
- Link to v3: https://lore.kernel.org/r/20251016-gs101-pd-v3-0-7b30797396e7@linaro.org

Changes in v3:
- use additionalProperties, not unevaluatedProperties in patch 2
- fix path in $id in patch 2 (Rob)
- drop comment around 'select' in patch 2 (Rob)
- collect tags
- Link to v2: https://lore.kernel.org/r/20251009-gs101-pd-v2-0-3f4a6db2af39@linaro.org

Changes in v2:
- Krzysztof:
  - move google,gs101-pmu binding into separate file
  - mark devm_kstrdup_const() patch as fix
  - use bool for need_early_sync_state
  - merge patches 8 and 10 from v1 series into one patch
- collect tags
- Link to v1: https://lore.kernel.org/r/20251006-gs101-pd-v1-0-f0cb0c01ea7b@linaro.org

---
André Draszik (10):
      dt-bindings: soc: google: add google,gs101-dtzpc
      dt-bindings: power: samsung: add google,gs101-pd
      dt-bindings: soc: samsung: exynos-pmu: move gs101-pmu into separate binding
      dt-bindings: soc: google: gs101-pmu: allow power domains as children
      pmdomain: samsung: convert to using regmap
      pmdomain: samsung: don't hard-code offset for registers to 0 and 4
      pmdomain: samsung: add support for google,gs101-pd
      pmdomain: samsung: use dev_err() instead of pr_err()
      pmdomain: samsung: implement SMC to save / restore TZ config
      pmdomain: samsung: implement domain-supply regulator

 .../devicetree/bindings/power/pd-samsung.yaml      |  29 ++-
 .../bindings/soc/google/google,gs101-dtzpc.yaml    |  42 ++++
 .../bindings/soc/google/google,gs101-pmu.yaml      |  97 ++++++++
 .../bindings/soc/samsung/exynos-pmu.yaml           |  20 --
 MAINTAINERS                                        |   2 +
 drivers/pmdomain/samsung/exynos-pm-domains.c       | 254 ++++++++++++++++++---
 6 files changed, 395 insertions(+), 49 deletions(-)
---
base-commit: e3b32dcb9f23e3c3927ef3eec6a5842a988fb574
change-id: 20251001-gs101-pd-d4dc97d70a84

Best regards,
-- 
André Draszik <andre.draszik@linaro.org>

[PATCH v4 01/10] dt-bindings: soc: google: add google,gs101-dtzpc

[André Draszik]

The Exynos Distributed TruztZone Protection Control (D_TZPC) provides
an interface to the protection bits that are included in the TrustZone
design in a secure system. It configures each area of the memory as
secure or non-secure.

Signed-off-by: André Draszik <andre.draszik@linaro.org>
---
 .../bindings/soc/google/google,gs101-dtzpc.yaml    | 42 ++++++++++++++++++++++
 MAINTAINERS                                        |  1 +
 2 files changed, 43 insertions(+)

diff --git a/Documentation/devicetree/bindings/soc/google/google,gs101-dtzpc.yaml b/Documentation/devicetree/bindings/soc/google/google,gs101-dtzpc.yaml
new file mode 100644
index 0000000000000000000000000000000000000000..a8c61ce069d6910c47753bf14a792eb58e6ae182
--- /dev/null
+++ b/Documentation/devicetree/bindings/soc/google/google,gs101-dtzpc.yaml
@@ -0,0 +1,42 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/soc/google/google,gs101-dtzpc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Samsung Exynos Distributed TruztZone Protection Control.
+
+description:
+  Distributed TrustZone Protection Control (D_TZPC) provides an interface to the
+  protection bits that are included in the TrustZone design in a secure system.
+  It configures each area of the memory as secure or non-secure.
+
+maintainers:
+  - André Draszik <andre.draszik@linaro.org>
+
+properties:
+  compatible:
+    const: google,gs101-dtzpc
+
+  clocks:
+    maxItems: 1
+
+  reg:
+    maxItems: 1
+
+required:
+  - compatible
+  - clocks
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/google,gs101.h>
+
+    dtzpc_hsi0: dtzpc@11010000 {
+      compatible = "google,gs101-dtzpc";
+      reg = <0x11010000 0x10000>;
+      clocks = <&cmu_hsi0 CLK_GOUT_HSI0_D_TZPC_HSI0_PCLK>;
+    };
diff --git a/MAINTAINERS b/MAINTAINERS
index a56f8f00aebb938aa765a8a6d66dfeb7f062dac8..98b2ef47c809ac0232e6941c9483b19d7c798bb4 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -10833,6 +10833,7 @@ P:	Documentation/process/maintainer-soc-clean-dts.rst
 C:	irc://irc.oftc.net/pixel6-kernel-dev
 F:	Documentation/devicetree/bindings/clock/google,gs101-clock.yaml
 F:	Documentation/devicetree/bindings/phy/google,lga-usb-phy.yaml
+F:	Documentation/devicetree/bindings/soc/google/google,gs101-dtzpc.yaml
 F:	Documentation/devicetree/bindings/soc/google/google,gs101-pmu-intr-gen.yaml
 F:	Documentation/devicetree/bindings/usb/google,lga-dwc3.yaml
 F:	arch/arm64/boot/dts/exynos/google/

-- 
2.52.0.457.g6b5491de43-goog

[PATCH v4 02/10] dt-bindings: power: samsung: add google,gs101-pd

[André Draszik]

Add support for the Google gs101 version of the Exynos power domains. A
new compatible is needed because register fields have changed and
because power domain operations involve interfacing with the TrustZone
protection control on newer Exynos SoCs.

Signed-off-by: André Draszik <andre.draszik@linaro.org>

---
v4:
- add new vendor property samsung,dtzpc
- drop previous tags due to that
---
 .../devicetree/bindings/power/pd-samsung.yaml      | 29 +++++++++++++++++++---
 1 file changed, 26 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/power/pd-samsung.yaml b/Documentation/devicetree/bindings/power/pd-samsung.yaml
index 9c2c51133457112ca0098c043e123f0a02fa1291..4ba555e11b30e6a9aaed457bcb57765bf5b481e3 100644
--- a/Documentation/devicetree/bindings/power/pd-samsung.yaml
+++ b/Documentation/devicetree/bindings/power/pd-samsung.yaml
@@ -13,12 +13,10 @@ description: |+
   Exynos processors include support for multiple power domains which are used
   to gate power to one or more peripherals on the processor.
 
-allOf:
-  - $ref: power-domain.yaml#
-
 properties:
   compatible:
     enum:
+      - google,gs101-pd
       - samsung,exynos4210-pd
       - samsung,exynos5433-pd
 
@@ -44,11 +42,28 @@ properties:
   power-domains:
     maxItems: 1
 
+  samsung,dtzpc:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description:
+      Distributed TrustZone Protection Control (DTZPC) node.
+
 required:
   - compatible
   - "#power-domain-cells"
   - reg
 
+allOf:
+  - $ref: power-domain.yaml#
+  - if:
+      not:
+        properties:
+          compatible:
+            contains:
+              const: google,gs101-pd
+    then:
+      properties:
+        samsung,dtzpc: false
+
 unevaluatedProperties: false
 
 examples:
@@ -66,3 +81,11 @@ examples:
         #power-domain-cells = <0>;
         label = "MFC";
     };
+
+    power-domain@2080 {
+        compatible = "google,gs101-pd";
+        reg = <0x2080 0x80>;
+        #power-domain-cells = <0>;
+        label = "hsi0";
+        samsung,dtzpc = <&dtzpc_hsi0>;
+    };

-- 
2.52.0.457.g6b5491de43-goog

[PATCH v4 03/10] dt-bindings: soc: samsung: exynos-pmu: move gs101-pmu into separate binding

[André Draszik]

The gs101-pmu binding is going to acquire various additional (pattern)
properties that don't apply to other PMUs supported by this binding.

To enable this, move google,gs101-pmu into a separate binding.

Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: André Draszik <andre.draszik@linaro.org>
---
v4:
- update since 'syscon' was removed from gs101-pmu compatibles
- update since 'select:' was removed from google,gs101-pmu.yaml

v3:
- use additionalProperties, not unevaluatedProperties
- fix path in $id (Rob)
- drop comment around 'select' (Rob)
---
 .../bindings/soc/google/google,gs101-pmu.yaml      | 56 ++++++++++++++++++++++
 .../bindings/soc/samsung/exynos-pmu.yaml           | 20 --------
 MAINTAINERS                                        |  1 +
 3 files changed, 57 insertions(+), 20 deletions(-)

diff --git a/Documentation/devicetree/bindings/soc/google/google,gs101-pmu.yaml b/Documentation/devicetree/bindings/soc/google/google,gs101-pmu.yaml
new file mode 100644
index 0000000000000000000000000000000000000000..a06bd8ec3c20faf0b364d3d3ef1763502c2b09cf
--- /dev/null
+++ b/Documentation/devicetree/bindings/soc/google/google,gs101-pmu.yaml
@@ -0,0 +1,56 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/soc/google/google,gs101-pmu.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Google GS101 Power Management Unit (PMU)
+
+maintainers:
+  - André Draszik <andre.draszik@linaro.org>
+
+properties:
+  compatible:
+    const: google,gs101-pmu
+
+  reg:
+    maxItems: 1
+
+  reboot-mode:
+    $ref: /schemas/power/reset/syscon-reboot-mode.yaml
+    type: object
+    description:
+      Reboot mode to alter bootloader behavior for the next boot
+
+  syscon-poweroff:
+    $ref: /schemas/power/reset/syscon-poweroff.yaml#
+    type: object
+    description:
+      Node for power off method
+
+  syscon-reboot:
+    $ref: /schemas/power/reset/syscon-reboot.yaml#
+    type: object
+    description:
+      Node for reboot method
+
+  google,pmu-intr-gen-syscon:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description:
+      Phandle to PMU interrupt generation interface.
+
+required:
+  - compatible
+  - reg
+  - google,pmu-intr-gen-syscon
+
+additionalProperties: false
+
+examples:
+  - |
+    system-controller@17460000 {
+        compatible = "google,gs101-pmu";
+        reg = <0x17460000 0x10000>;
+
+        google,pmu-intr-gen-syscon = <&pmu_intr_gen>;
+    };
diff --git a/Documentation/devicetree/bindings/soc/samsung/exynos-pmu.yaml b/Documentation/devicetree/bindings/soc/samsung/exynos-pmu.yaml
index 76ce7e98c10f3738e7de5579904260dd906507c9..09368dbb6de6898e2988c398b2506f2c2b4e73bc 100644
--- a/Documentation/devicetree/bindings/soc/samsung/exynos-pmu.yaml
+++ b/Documentation/devicetree/bindings/soc/samsung/exynos-pmu.yaml
@@ -12,8 +12,6 @@ maintainers:
 properties:
   compatible:
     oneOf:
-      - enum:
-          - google,gs101-pmu
       - items:
           - enum:
               - samsung,exynos3250-pmu
@@ -110,11 +108,6 @@ properties:
     description:
       Node for reboot method
 
-  google,pmu-intr-gen-syscon:
-    $ref: /schemas/types.yaml#/definitions/phandle
-    description:
-      Phandle to PMU interrupt generation interface.
-
 required:
   - compatible
   - reg
@@ -176,19 +169,6 @@ allOf:
       properties:
         dp-phy: false
 
-  - if:
-      properties:
-        compatible:
-          contains:
-            enum:
-              - google,gs101-pmu
-    then:
-      required:
-        - google,pmu-intr-gen-syscon
-    else:
-      properties:
-        google,pmu-intr-gen-syscon: false
-
 examples:
   - |
     #include <dt-bindings/clock/exynos5250.h>
diff --git a/MAINTAINERS b/MAINTAINERS
index 98b2ef47c809ac0232e6941c9483b19d7c798bb4..79a58769e9cb33d9bd6190c74d55461e77965af5 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -10834,6 +10834,7 @@ C:	irc://irc.oftc.net/pixel6-kernel-dev
 F:	Documentation/devicetree/bindings/clock/google,gs101-clock.yaml
 F:	Documentation/devicetree/bindings/phy/google,lga-usb-phy.yaml
 F:	Documentation/devicetree/bindings/soc/google/google,gs101-dtzpc.yaml
+F:	Documentation/devicetree/bindings/soc/google/google,gs101-pmu.yaml
 F:	Documentation/devicetree/bindings/soc/google/google,gs101-pmu-intr-gen.yaml
 F:	Documentation/devicetree/bindings/usb/google,lga-dwc3.yaml
 F:	arch/arm64/boot/dts/exynos/google/

-- 
2.52.0.457.g6b5491de43-goog

[PATCH v4 04/10] dt-bindings: soc: google: gs101-pmu: allow power domains as children

[André Draszik]

The power domains are a property of / implemented in the PMU. As such,
they should be modelled as child nodes of the PMU.

Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: André Draszik <andre.draszik@linaro.org>
---
v4:
- consistent quoting using " (Krzysztof)
- add samsung,dtzpc to example

Note: Ideally, the newly added properties (ranges, etc.) should only be
'required' if "^power-domain@[0-9a-f]+$" exists as a patternProperty,
as they're needed only in that case. As-is, this patch now causes
warnings for existing DTs as they don't specify the new properties (and
they shouldn't need to). Only if DTs are updated to include
power-domains, such an update should also add the new properties.

I've not been able to come up with the correct schema syntax to achieve
that. dependencies, dependentRequired, and dependentSchemas don't seem
to support patterns. Similarly,
  - if:
      required:
        - ...
    then:
      required:
        - ...

doesn't allow patterns in the 'if' block (or I didn't get the syntax
right).

Rob said in
https://lore.kernel.org/all/20251010141357.GA219719-robh@kernel.org/
that this is a known limitation in json-schema.
---
 .../bindings/soc/google/google,gs101-pmu.yaml      | 41 ++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/Documentation/devicetree/bindings/soc/google/google,gs101-pmu.yaml b/Documentation/devicetree/bindings/soc/google/google,gs101-pmu.yaml
index a06bd8ec3c20faf0b364d3d3ef1763502c2b09cf..c1ee9575092a3ab17873d228a88468addb62d838 100644
--- a/Documentation/devicetree/bindings/soc/google/google,gs101-pmu.yaml
+++ b/Documentation/devicetree/bindings/soc/google/google,gs101-pmu.yaml
@@ -16,6 +16,14 @@ properties:
   reg:
     maxItems: 1
 
+  "#address-cells":
+    const: 1
+
+  "#size-cells":
+    const: 1
+
+  ranges: true
+
   reboot-mode:
     $ref: /schemas/power/reset/syscon-reboot-mode.yaml
     type: object
@@ -39,9 +47,23 @@ properties:
     description:
       Phandle to PMU interrupt generation interface.
 
+patternProperties:
+  "^power-domain@[0-9a-f]+$":
+    type: object
+    description: Child node describing one power domain within the PMU
+
+    additionalProperties: true
+
+    properties:
+      compatible:
+        const: google,gs101-pd
+
 required:
   - compatible
   - reg
+  - '#address-cells'
+  - '#size-cells'
+  - ranges
   - google,pmu-intr-gen-syscon
 
 additionalProperties: false
@@ -51,6 +73,25 @@ examples:
     system-controller@17460000 {
         compatible = "google,gs101-pmu";
         reg = <0x17460000 0x10000>;
+        #address-cells = <1>;
+        #size-cells = <1>;
+        ranges;
 
         google,pmu-intr-gen-syscon = <&pmu_intr_gen>;
+
+        pd_g3d: power-domain@1e00 {
+            compatible = "google,gs101-pd";
+            reg = <0x1e00 0x80>;
+            #power-domain-cells = <0>;
+            label = "g3d";
+            samsung,dtzpc = <&pd_g3d>;
+        };
+
+        power-domain@2000 {
+            compatible = "google,gs101-pd";
+            reg = <0x2000 0x80>;
+            #power-domain-cells = <0>;
+            power-domains = <&pd_g3d>;
+            label = "embedded_g3d";
+        };
     };

-- 
2.52.0.457.g6b5491de43-goog

[PATCH v4 05/10] pmdomain: samsung: convert to using regmap

[André Draszik]

On platforms such as Google gs101, direct mmio register access to the
PMU registers doesn't necessarily work and access must happen via a
regmap created by the PMU driver instead.

In preparation for supporting such SoCs convert the existing mmio
accesses to using a regmap wrapper.

With this change in place, a follow-up patch can update the driver to
optionally acquire the PMU-created regmap without having to change the
rest of the code.

Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: André Draszik <andre.draszik@linaro.org>
---
There is one checkpatch warning, relating to the non-const
regmap_config. It can not easily be made const at this stage, but a
follow-up patch allows us to make it const and the warning will go away
anyway.

v4:
- rework the loop in exynos_pd_power() slightly, to not return 0 early
  to allow more code to be run after pd on/off register write without
  changing the loop again, required for gs101.
- add error message in case first regmap write in exynos_pd_power() fails
---
 drivers/pmdomain/samsung/exynos-pm-domains.c | 83 +++++++++++++++++++++-------
 1 file changed, 62 insertions(+), 21 deletions(-)

diff --git a/drivers/pmdomain/samsung/exynos-pm-domains.c b/drivers/pmdomain/samsung/exynos-pm-domains.c
index 5c3aa898308793d424fb761c58ca01ba2580aeb5..3bcba7d38ac1572ef4bc2f4052c904dd6c4a7bfd 100644
--- a/drivers/pmdomain/samsung/exynos-pm-domains.c
+++ b/drivers/pmdomain/samsung/exynos-pm-domains.c
@@ -9,15 +9,14 @@
 // conjunction with runtime-pm. Support for both device-tree and non-device-tree
 // based power domain support is included.
 
-#include <linux/io.h>
 #include <linux/err.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/pm_domain.h>
 #include <linux/delay.h>
 #include <linux/of.h>
-#include <linux/of_address.h>
 #include <linux/pm_runtime.h>
+#include <linux/regmap.h>
 
 struct exynos_pm_domain_config {
 	/* Value for LOCAL_PWR_CFG and STATUS fields for each domain */
@@ -28,7 +27,7 @@ struct exynos_pm_domain_config {
  * Exynos specific wrapper around the generic power domain
  */
 struct exynos_pm_domain {
-	void __iomem *base;
+	struct regmap *regmap;
 	struct generic_pm_domain pd;
 	u32 local_pwr_cfg;
 };
@@ -36,31 +35,42 @@ struct exynos_pm_domain {
 static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on)
 {
 	struct exynos_pm_domain *pd;
-	void __iomem *base;
 	u32 timeout, pwr;
-	char *op;
+	int err;
 
 	pd = container_of(domain, struct exynos_pm_domain, pd);
-	base = pd->base;
 
 	pwr = power_on ? pd->local_pwr_cfg : 0;
-	writel_relaxed(pwr, base);
+	err = regmap_write(pd->regmap, 0, pwr);
+	if (err) {
+		pr_err("Regmap write for power domain %s %sable failed: %d\n",
+		       domain->name, power_on ? "en" : "dis", err);
+		return err;
+	}
 
 	/* Wait max 1ms */
 	timeout = 10;
-
-	while ((readl_relaxed(base + 0x4) & pd->local_pwr_cfg) != pwr) {
-		if (!timeout) {
-			op = (power_on) ? "enable" : "disable";
-			pr_err("Power domain %s %s failed\n", domain->name, op);
-			return -ETIMEDOUT;
+	while (timeout-- > 0) {
+		unsigned int val;
+
+		err = regmap_read(pd->regmap, 0x4, &val);
+		if (err || ((val & pd->local_pwr_cfg) != pwr)) {
+			cpu_relax();
+			usleep_range(80, 100);
+			continue;
 		}
-		timeout--;
-		cpu_relax();
-		usleep_range(80, 100);
+
+		break;
 	}
 
-	return 0;
+	if (!timeout && !err)
+		/* Only return timeout if no other error also occurred. */
+		err = -ETIMEDOUT;
+	if (err)
+		pr_err("Power domain %s %sable failed: %d\n", domain->name,
+		       power_on ? "en" : "dis", err);
+
+	return err;
 }
 
 static int exynos_pd_power_on(struct generic_pm_domain *domain)
@@ -109,8 +119,18 @@ static int exynos_pd_probe(struct platform_device *pdev)
 	struct device_node *np = dev->of_node;
 	struct of_phandle_args child, parent;
 	struct exynos_pm_domain *pd;
+	struct resource *res;
+	void __iomem *base;
+	unsigned int val;
 	int on, ret;
 
+	struct regmap_config reg_config = {
+		.reg_bits = 32,
+		.val_bits = 32,
+		.reg_stride = 4,
+		.use_relaxed_mmio = true,
+	};
+
 	pm_domain_cfg = of_device_get_match_data(dev);
 	pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
 	if (!pd)
@@ -120,9 +140,26 @@ static int exynos_pd_probe(struct platform_device *pdev)
 	if (!pd->pd.name)
 		return -ENOMEM;
 
-	pd->base = of_iomap(np, 0);
-	if (!pd->base)
-		return -ENODEV;
+	/*
+	 * The resource typically points into the address space of the PMU.
+	 * Therefore, avoid using devm_platform_get_and_ioremap_resource() and
+	 * instead use platform_get_resource() and devm_ioremap() to avoid
+	 * conflicts due to address space overlap.
+	 */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return dev_err_probe(dev, -ENXIO, "missing IO resources");
+
+	base = devm_ioremap(dev, res->start, resource_size(res));
+	if (!base)
+		return dev_err_probe(dev, -ENOMEM,
+				     "failed to ioremap PMU registers");
+
+	reg_config.max_register = resource_size(res) - reg_config.reg_stride;
+	pd->regmap = devm_regmap_init_mmio(dev, base, &reg_config);
+	if (IS_ERR(pd->regmap))
+		return dev_err_probe(dev, PTR_ERR(base),
+				     "failed to init regmap");
 
 	pd->pd.power_off = exynos_pd_power_off;
 	pd->pd.power_on = exynos_pd_power_on;
@@ -137,7 +174,11 @@ static int exynos_pd_probe(struct platform_device *pdev)
 	    of_device_is_compatible(np, "samsung,exynos4210-pd"))
 		exynos_pd_power_off(&pd->pd);
 
-	on = readl_relaxed(pd->base + 0x4) & pd->local_pwr_cfg;
+	ret = regmap_read(pd->regmap, 0x4, &val);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to read status");
+
+	on = val & pd->local_pwr_cfg;
 
 	pm_genpd_init(&pd->pd, NULL, !on);
 	ret = of_genpd_add_provider_simple(np, &pd->pd);

-- 
2.52.0.457.g6b5491de43-goog

[PATCH v4 06/10] pmdomain: samsung: don't hard-code offset for registers to 0 and 4

[André Draszik]

On platforms such as Google gs101, direct mmio register access to the
PMU registers doesn't necessarily work and access must happen via a
regmap created by the PMU driver instead.

When such a regmap is used it will cover the complete PMU memory region
rather than individual power domains. This means the register offsets
for the configuration and status registers will have to take the power
domain offsets into account, rather than unconditionally hard-coding 0
and 4 respectively.

Update the code to allow that.

Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: André Draszik <andre.draszik@linaro.org>
---
 drivers/pmdomain/samsung/exynos-pm-domains.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/pmdomain/samsung/exynos-pm-domains.c b/drivers/pmdomain/samsung/exynos-pm-domains.c
index 3bcba7d38ac1572ef4bc2f4052c904dd6c4a7bfd..8df46b41f9bc8f0b2a03300169a4b52457faaf4d 100644
--- a/drivers/pmdomain/samsung/exynos-pm-domains.c
+++ b/drivers/pmdomain/samsung/exynos-pm-domains.c
@@ -30,6 +30,8 @@ struct exynos_pm_domain {
 	struct regmap *regmap;
 	struct generic_pm_domain pd;
 	u32 local_pwr_cfg;
+	u32 configuration_reg;
+	u32 status_reg;
 };
 
 static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on)
@@ -41,7 +43,7 @@ static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on)
 	pd = container_of(domain, struct exynos_pm_domain, pd);
 
 	pwr = power_on ? pd->local_pwr_cfg : 0;
-	err = regmap_write(pd->regmap, 0, pwr);
+	err = regmap_write(pd->regmap, pd->configuration_reg, pwr);
 	if (err) {
 		pr_err("Regmap write for power domain %s %sable failed: %d\n",
 		       domain->name, power_on ? "en" : "dis", err);
@@ -53,7 +55,7 @@ static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on)
 	while (timeout-- > 0) {
 		unsigned int val;
 
-		err = regmap_read(pd->regmap, 0x4, &val);
+		err = regmap_read(pd->regmap, pd->status_reg, &val);
 		if (err || ((val & pd->local_pwr_cfg) != pwr)) {
 			cpu_relax();
 			usleep_range(80, 100);
@@ -164,6 +166,8 @@ static int exynos_pd_probe(struct platform_device *pdev)
 	pd->pd.power_off = exynos_pd_power_off;
 	pd->pd.power_on = exynos_pd_power_on;
 	pd->local_pwr_cfg = pm_domain_cfg->local_pwr_cfg;
+	pd->configuration_reg += 0;
+	pd->status_reg += 4;
 
 	/*
 	 * Some Samsung platforms with bootloaders turning on the splash-screen
@@ -174,7 +178,7 @@ static int exynos_pd_probe(struct platform_device *pdev)
 	    of_device_is_compatible(np, "samsung,exynos4210-pd"))
 		exynos_pd_power_off(&pd->pd);
 
-	ret = regmap_read(pd->regmap, 0x4, &val);
+	ret = regmap_read(pd->regmap, pd->status_reg, &val);
 	if (ret)
 		return dev_err_probe(dev, ret, "failed to read status");
 

-- 
2.52.0.457.g6b5491de43-goog

[PATCH v4 07/10] pmdomain: samsung: add support for google,gs101-pd

[André Draszik]

On Google gs101, direct mmio register access to the PMU registers
doesn't work and access must happen via a regmap created by the PMU
driver instead.

Add a flag to the device match data to denote this case, and obtain
the regmap using the parent node in DT if true, while keeping to use
the traditional direct mmio regmap otherwise.

Additionally, the status is just one bit on gs101.

Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: André Draszik <andre.draszik@linaro.org>

---
v4:
- add 'use_parent_regmap' flag instead of going by 'syscon' compatible
  in parent, as it's not a given that the parent provides a syscon-
  compatible regmap (it actually doesn't anymore after recent changes
  on gs101)

I've still kept Marek's Tested-by from v3, as legacy Exynos code
doesn't change.
---
 drivers/pmdomain/samsung/exynos-pm-domains.c | 66 +++++++++++++++++++---------
 1 file changed, 46 insertions(+), 20 deletions(-)

diff --git a/drivers/pmdomain/samsung/exynos-pm-domains.c b/drivers/pmdomain/samsung/exynos-pm-domains.c
index 8df46b41f9bc8f0b2a03300169a4b52457faaf4d..2214d9f32d5967b60e84f68f4e99a725d66a39eb 100644
--- a/drivers/pmdomain/samsung/exynos-pm-domains.c
+++ b/drivers/pmdomain/samsung/exynos-pm-domains.c
@@ -12,6 +12,7 @@
 #include <linux/err.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
+#include <linux/mfd/syscon.h>
 #include <linux/pm_domain.h>
 #include <linux/delay.h>
 #include <linux/of.h>
@@ -21,6 +22,7 @@
 struct exynos_pm_domain_config {
 	/* Value for LOCAL_PWR_CFG and STATUS fields for each domain */
 	u32 local_pwr_cfg;
+	bool use_parent_regmap;
 };
 
 /*
@@ -93,8 +95,16 @@ static const struct exynos_pm_domain_config exynos5433_cfg = {
 	.local_pwr_cfg		= 0xf,
 };
 
+static const struct exynos_pm_domain_config gs101_cfg = {
+	.local_pwr_cfg		= BIT(0),
+	.use_parent_regmap	= true,
+};
+
 static const struct of_device_id exynos_pm_domain_of_match[] = {
 	{
+		.compatible = "google,gs101-pd",
+		.data = &gs101_cfg,
+	}, {
 		.compatible = "samsung,exynos4210-pd",
 		.data = &exynos4210_cfg,
 	}, {
@@ -122,17 +132,9 @@ static int exynos_pd_probe(struct platform_device *pdev)
 	struct of_phandle_args child, parent;
 	struct exynos_pm_domain *pd;
 	struct resource *res;
-	void __iomem *base;
 	unsigned int val;
 	int on, ret;
 
-	struct regmap_config reg_config = {
-		.reg_bits = 32,
-		.val_bits = 32,
-		.reg_stride = 4,
-		.use_relaxed_mmio = true,
-	};
-
 	pm_domain_cfg = of_device_get_match_data(dev);
 	pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
 	if (!pd)
@@ -143,25 +145,49 @@ static int exynos_pd_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	/*
-	 * The resource typically points into the address space of the PMU.
+	 * The resource typically points into the address space of the PMU and
+	 * we have to consider two cases:
+	 *   1) some implementations require a custom regmap (from PMU parent)
+	 *   2) this driver might map the same addresses as the PMU driver
 	 * Therefore, avoid using devm_platform_get_and_ioremap_resource() and
-	 * instead use platform_get_resource() and devm_ioremap() to avoid
+	 * instead use platform_get_resource() here, and below for case 1) use
+	 * syscon_node_to_regmap() while for case 2) use devm_ioremap() to avoid
 	 * conflicts due to address space overlap.
 	 */
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!res)
 		return dev_err_probe(dev, -ENXIO, "missing IO resources");
 
-	base = devm_ioremap(dev, res->start, resource_size(res));
-	if (!base)
-		return dev_err_probe(dev, -ENOMEM,
-				     "failed to ioremap PMU registers");
-
-	reg_config.max_register = resource_size(res) - reg_config.reg_stride;
-	pd->regmap = devm_regmap_init_mmio(dev, base, &reg_config);
-	if (IS_ERR(pd->regmap))
-		return dev_err_probe(dev, PTR_ERR(base),
-				     "failed to init regmap");
+	if (pm_domain_cfg->use_parent_regmap) {
+		pd->regmap = syscon_node_to_regmap(dev->parent->of_node);
+		if (IS_ERR(pd->regmap))
+			return dev_err_probe(dev, PTR_ERR(pd->regmap),
+					     "failed to acquire PMU regmap");
+
+		pd->configuration_reg = res->start;
+		pd->status_reg = res->start;
+	} else {
+		void __iomem *base;
+
+		const struct regmap_config reg_config = {
+			.reg_bits = 32,
+			.val_bits = 32,
+			.reg_stride = 4,
+			.use_relaxed_mmio = true,
+			.max_register = (resource_size(res)
+					 - reg_config.reg_stride),
+		};
+
+		base = devm_ioremap(dev, res->start, resource_size(res));
+		if (!base)
+			return dev_err_probe(dev, -ENOMEM,
+					     "failed to ioremap PMU registers");
+
+		pd->regmap = devm_regmap_init_mmio(dev, base, &reg_config);
+		if (IS_ERR(pd->regmap))
+			return dev_err_probe(dev, PTR_ERR(base),
+					     "failed to init regmap");
+	}
 
 	pd->pd.power_off = exynos_pd_power_off;
 	pd->pd.power_on = exynos_pd_power_on;

-- 
2.52.0.457.g6b5491de43-goog

[PATCH v4 08/10] pmdomain: samsung: use dev_err() instead of pr_err()

[André Draszik]

dev_err() gives us more consistent error messages, which include the
device. Switch to using dev_err().

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: André Draszik <andre.draszik@linaro.org>
---
 drivers/pmdomain/samsung/exynos-pm-domains.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/pmdomain/samsung/exynos-pm-domains.c b/drivers/pmdomain/samsung/exynos-pm-domains.c
index 2214d9f32d5967b60e84f68f4e99a725d66a39eb..41a232b3cdaf0f4be413b25d9373b99c6a3db602 100644
--- a/drivers/pmdomain/samsung/exynos-pm-domains.c
+++ b/drivers/pmdomain/samsung/exynos-pm-domains.c
@@ -30,6 +30,7 @@ struct exynos_pm_domain_config {
  */
 struct exynos_pm_domain {
 	struct regmap *regmap;
+	struct device *dev;
 	struct generic_pm_domain pd;
 	u32 local_pwr_cfg;
 	u32 configuration_reg;
@@ -47,8 +48,9 @@ static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on)
 	pwr = power_on ? pd->local_pwr_cfg : 0;
 	err = regmap_write(pd->regmap, pd->configuration_reg, pwr);
 	if (err) {
-		pr_err("Regmap write for power domain %s %sable failed: %d\n",
-		       domain->name, power_on ? "en" : "dis", err);
+		dev_err(pd->dev,
+			"Regmap write for power domain %s %sable failed: %d\n",
+			domain->name, power_on ? "en" : "dis", err);
 		return err;
 	}
 
@@ -71,8 +73,8 @@ static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on)
 		/* Only return timeout if no other error also occurred. */
 		err = -ETIMEDOUT;
 	if (err)
-		pr_err("Power domain %s %sable failed: %d\n", domain->name,
-		       power_on ? "en" : "dis", err);
+		dev_err(pd->dev, "Power domain %s %sable failed: %d\n",
+			domain->name, power_on ? "en" : "dis", err);
 
 	return err;
 }
@@ -140,6 +142,8 @@ static int exynos_pd_probe(struct platform_device *pdev)
 	if (!pd)
 		return -ENOMEM;
 
+	pd->dev = dev;
+
 	pd->pd.name = exynos_get_domain_name(dev, np);
 	if (!pd->pd.name)
 		return -ENOMEM;

-- 
2.52.0.457.g6b5491de43-goog

[PATCH v4 09/10] pmdomain: samsung: implement SMC to save / restore TZ config

[André Draszik]

Newer Exynos platforms have a Distributed Trust Zone Protection Control
(DTZPC) linked to each power domain. It controls the access permissions
to various registers from secure and non-secure world. An SMC call is
required to instruct the firmware that the power domain is about to be
turned off and again once it was turned on. This allows the firmware to
save and restore the DTZPC configuration. Without, register access to
various registers becomes impossible from Linux (causing SError), as
the PoR configuration doesn't allow access.

Neither the requirement for the SMC call, nor its arguments appear to
be specific to gs101, as at least Exynos E850 also uses the same as can
be seen in [1], hence prefix the new macros simply with EXYNOS_.

At least on gs101, this SMC call isn't implemented for all power
domains (e.g. it's missing for HSI2 (UFS)), therefore we issue a test
SMC to store the configuration during probe, and if it fails we mark a
domain as always-on to avoid the SErrors and to avoid unnecessarily
retrying for each domain on/off.

Link: https://lore.kernel.org/all/20230308233822.31180-4-semen.protsenko@linaro.org/ [1]
Signed-off-by: André Draszik <andre.draszik@linaro.org>
---
 drivers/pmdomain/samsung/exynos-pm-domains.c | 96 ++++++++++++++++++++++++++--
 1 file changed, 90 insertions(+), 6 deletions(-)

diff --git a/drivers/pmdomain/samsung/exynos-pm-domains.c b/drivers/pmdomain/samsung/exynos-pm-domains.c
index 41a232b3cdaf0f4be413b25d9373b99c6a3db602..f59986b56213dfcc470d9cccc61a36a81954bdcc 100644
--- a/drivers/pmdomain/samsung/exynos-pm-domains.c
+++ b/drivers/pmdomain/samsung/exynos-pm-domains.c
@@ -9,6 +9,7 @@
 // conjunction with runtime-pm. Support for both device-tree and non-device-tree
 // based power domain support is included.
 
+#include <linux/arm-smccc.h>
 #include <linux/err.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
@@ -16,12 +17,19 @@
 #include <linux/pm_domain.h>
 #include <linux/delay.h>
 #include <linux/of.h>
+#include <linux/of_address.h>
 #include <linux/pm_runtime.h>
 #include <linux/regmap.h>
 
+#define EXYNOS_SMC_CMD_PREPARE_PD_ONOFF		0x82000410
+#define EXYNOS_GET_IN_PD_DOWN			0
+#define EXYNOS_WAKEUP_PD_DOWN			1
+#define EXYNOS_RUNTIME_PM_TZPC_GROUP		2
+
 struct exynos_pm_domain_config {
 	/* Value for LOCAL_PWR_CFG and STATUS fields for each domain */
 	u32 local_pwr_cfg;
+	u32 smc_offset;
 	bool use_parent_regmap;
 };
 
@@ -32,11 +40,28 @@ struct exynos_pm_domain {
 	struct regmap *regmap;
 	struct device *dev;
 	struct generic_pm_domain pd;
-	u32 local_pwr_cfg;
+	const struct exynos_pm_domain_config *cfg;
 	u32 configuration_reg;
 	u32 status_reg;
+	phys_addr_t ac_pa;
 };
 
+static int exynos_pd_access_controller_power(struct exynos_pm_domain *pd,
+					     bool power_on)
+{
+	struct arm_smccc_res res;
+
+	if (!pd->ac_pa || !pd->cfg->smc_offset)
+		return 0;
+
+	arm_smccc_smc(EXYNOS_SMC_CMD_PREPARE_PD_ONOFF,
+		      power_on ? EXYNOS_WAKEUP_PD_DOWN : EXYNOS_GET_IN_PD_DOWN,
+		      pd->ac_pa + pd->cfg->smc_offset,
+		      EXYNOS_RUNTIME_PM_TZPC_GROUP, 0, 0, 0, 0, &res);
+
+	return res.a0;
+}
+
 static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on)
 {
 	struct exynos_pm_domain *pd;
@@ -45,7 +70,17 @@ static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on)
 
 	pd = container_of(domain, struct exynos_pm_domain, pd);
 
-	pwr = power_on ? pd->local_pwr_cfg : 0;
+	if (!power_on) {
+		err = exynos_pd_access_controller_power(pd, power_on);
+		if (err) {
+			dev_err(pd->dev,
+				"SMC for power domain %s %sable failed: %d\n",
+				domain->name, power_on ? "en" : "dis", err);
+			return err;
+		}
+	}
+
+	pwr = power_on ? pd->cfg->local_pwr_cfg : 0;
 	err = regmap_write(pd->regmap, pd->configuration_reg, pwr);
 	if (err) {
 		dev_err(pd->dev,
@@ -60,7 +95,7 @@ static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on)
 		unsigned int val;
 
 		err = regmap_read(pd->regmap, pd->status_reg, &val);
-		if (err || ((val & pd->local_pwr_cfg) != pwr)) {
+		if (err || ((val & pd->cfg->local_pwr_cfg) != pwr)) {
 			cpu_relax();
 			usleep_range(80, 100);
 			continue;
@@ -72,9 +107,21 @@ static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on)
 	if (!timeout && !err)
 		/* Only return timeout if no other error also occurred. */
 		err = -ETIMEDOUT;
-	if (err)
+	if (err) {
 		dev_err(pd->dev, "Power domain %s %sable failed: %d\n",
 			domain->name, power_on ? "en" : "dis", err);
+		return err;
+	}
+
+	if (power_on) {
+		err = exynos_pd_access_controller_power(pd, power_on);
+		if (err) {
+			dev_err(pd->dev,
+				"SMC for power domain %s %sable failed: %d\n",
+				domain->name, power_on ? "en" : "dis", err);
+			return err;
+		}
+	}
 
 	return err;
 }
@@ -99,6 +146,7 @@ static const struct exynos_pm_domain_config exynos5433_cfg = {
 
 static const struct exynos_pm_domain_config gs101_cfg = {
 	.local_pwr_cfg		= BIT(0),
+	.smc_offset		= 0x0204,
 	.use_parent_regmap	= true,
 };
 
@@ -126,6 +174,38 @@ static const char *exynos_get_domain_name(struct device *dev,
 	return devm_kstrdup_const(dev, name, GFP_KERNEL);
 }
 
+static int exynos_pd_get_access_controller(struct exynos_pm_domain *pd)
+{
+	struct device_node *ac_np;
+	struct resource ac_res;
+	int ret;
+
+	ac_np = of_parse_phandle(pd->dev->of_node, "samsung,dtzpc", 0);
+	if (!ac_np)
+		return 0;
+
+	ret = of_address_to_resource(ac_np, 0, &ac_res);
+	of_node_put(ac_np);
+	if (ret)
+		return dev_err_probe(pd->dev, ret,
+				     "failed to get access controller\n");
+
+	pd->ac_pa = ac_res.start;
+
+	/*
+	 * For some domains, TZ save/restore might not be implemented. If that
+	 * is the case, simply mark it as always on, as otherwise a power cycle
+	 * will lead to lost TZ configuration, making it impossible to access
+	 * registers from Linux afterwards.
+	 */
+	if (exynos_pd_access_controller_power(pd, false) == -ENOENT) {
+		pd->ac_pa = 0;
+		pd->pd.flags |= GENPD_FLAG_ALWAYS_ON;
+	}
+
+	return 0;
+}
+
 static int exynos_pd_probe(struct platform_device *pdev)
 {
 	const struct exynos_pm_domain_config *pm_domain_cfg;
@@ -195,10 +275,14 @@ static int exynos_pd_probe(struct platform_device *pdev)
 
 	pd->pd.power_off = exynos_pd_power_off;
 	pd->pd.power_on = exynos_pd_power_on;
-	pd->local_pwr_cfg = pm_domain_cfg->local_pwr_cfg;
+	pd->cfg = pm_domain_cfg;
 	pd->configuration_reg += 0;
 	pd->status_reg += 4;
 
+	ret = exynos_pd_get_access_controller(pd);
+	if (ret)
+		return ret;
+
 	/*
 	 * Some Samsung platforms with bootloaders turning on the splash-screen
 	 * and handing it over to the kernel, requires the power-domains to be
@@ -212,7 +296,7 @@ static int exynos_pd_probe(struct platform_device *pdev)
 	if (ret)
 		return dev_err_probe(dev, ret, "failed to read status");
 
-	on = val & pd->local_pwr_cfg;
+	on = val & pd->cfg->local_pwr_cfg;
 
 	pm_genpd_init(&pd->pd, NULL, !on);
 	ret = of_genpd_add_provider_simple(np, &pd->pd);

-- 
2.52.0.457.g6b5491de43-goog

[PATCH v4 10/10] pmdomain: samsung: implement domain-supply regulator

[André Draszik]

Some power domains on Exynos are fed by a regulator rail and therefore
regulator control needs be implemented for Exynos power domains.

On Google gs101, HSI0 (USB) is one example of such a power domain.

While at it, add a to_exynos_pd() to avoid direct use of
container_of() in various additional places, and update existing code
to use it.

Signed-off-by: André Draszik <andre.draszik@linaro.org>
---
 drivers/pmdomain/samsung/exynos-pm-domains.c | 53 +++++++++++++++++++++++++---
 1 file changed, 48 insertions(+), 5 deletions(-)

diff --git a/drivers/pmdomain/samsung/exynos-pm-domains.c b/drivers/pmdomain/samsung/exynos-pm-domains.c
index f59986b56213dfcc470d9cccc61a36a81954bdcc..ed7a5807555bcf86e4ec88166bfd5f6c06c9322c 100644
--- a/drivers/pmdomain/samsung/exynos-pm-domains.c
+++ b/drivers/pmdomain/samsung/exynos-pm-domains.c
@@ -20,12 +20,15 @@
 #include <linux/of_address.h>
 #include <linux/pm_runtime.h>
 #include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
 
 #define EXYNOS_SMC_CMD_PREPARE_PD_ONOFF		0x82000410
 #define EXYNOS_GET_IN_PD_DOWN			0
 #define EXYNOS_WAKEUP_PD_DOWN			1
 #define EXYNOS_RUNTIME_PM_TZPC_GROUP		2
 
+#define to_exynos_pd(gpd) container_of_const(gpd, struct exynos_pm_domain, pd)
+
 struct exynos_pm_domain_config {
 	/* Value for LOCAL_PWR_CFG and STATUS fields for each domain */
 	u32 local_pwr_cfg;
@@ -39,6 +42,7 @@ struct exynos_pm_domain_config {
 struct exynos_pm_domain {
 	struct regmap *regmap;
 	struct device *dev;
+	struct regulator *supply;
 	struct generic_pm_domain pd;
 	const struct exynos_pm_domain_config *cfg;
 	u32 configuration_reg;
@@ -64,12 +68,10 @@ static int exynos_pd_access_controller_power(struct exynos_pm_domain *pd,
 
 static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on)
 {
-	struct exynos_pm_domain *pd;
+	struct exynos_pm_domain *pd = to_exynos_pd(domain);
 	u32 timeout, pwr;
 	int err;
 
-	pd = container_of(domain, struct exynos_pm_domain, pd);
-
 	if (!power_on) {
 		err = exynos_pd_access_controller_power(pd, power_on);
 		if (err) {
@@ -126,14 +128,45 @@ static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on)
 	return err;
 }
 
+static int exynos_pd_regulator_enable(struct regulator *supply)
+{
+	return supply ? regulator_enable(supply) : 0;
+}
+
+static int exynos_pd_regulator_disable(struct regulator *supply)
+{
+	return supply ? regulator_disable(supply) : 0;
+}
+
 static int exynos_pd_power_on(struct generic_pm_domain *domain)
 {
-	return exynos_pd_power(domain, true);
+	struct exynos_pm_domain *pd = to_exynos_pd(domain);
+	int ret;
+
+	ret = exynos_pd_regulator_enable(pd->supply);
+	if (ret)
+		return ret;
+
+	ret = exynos_pd_power(domain, true);
+	if (ret)
+		exynos_pd_regulator_disable(pd->supply);
+
+	return ret;
 }
 
 static int exynos_pd_power_off(struct generic_pm_domain *domain)
 {
-	return exynos_pd_power(domain, false);
+	struct exynos_pm_domain *pd = to_exynos_pd(domain);
+	int ret;
+
+	ret = exynos_pd_power(domain, false);
+	if (ret)
+		return ret;
+
+	/* Ignore regulator errors - the domain was disabled after all. */
+	exynos_pd_regulator_disable(pd->supply);
+
+	return 0;
 }
 
 static const struct exynos_pm_domain_config exynos4210_cfg = {
@@ -283,6 +316,16 @@ static int exynos_pd_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
+	/* get the domain power supply if required */
+	pd->supply = devm_regulator_get_optional(dev, "domain");
+	if (IS_ERR(pd->supply)) {
+		if (PTR_ERR(pd->supply) != -ENODEV)
+			return dev_err_probe(dev, PTR_ERR(pd->supply),
+					     "failed to get domain supply");
+
+		pd->supply = NULL;
+	}
+
 	/*
 	 * Some Samsung platforms with bootloaders turning on the splash-screen
 	 * and handing it over to the kernel, requires the power-domains to be

-- 
2.52.0.457.g6b5491de43-goog

Re: [PATCH v4 00/10] pmdomain: samsung: add support for Google GS101

[Krzysztof Kozlowski]

On 28/01/2026 17:10, André Draszik wrote:
> Hi,
> 
> This series adds support for the power domains on Google GS101.
> 
> There are a few differences compared to SoCs already supported by this
> driver:
> * register access does not work via plain ioremap() / readl() /
>   writel().
>   Instead, the regmap created by the PMU driver must be used (which
>   uses Arm SMCC calls under the hood).
> * DTZPC: a call needs to be made before and after power domain off/on,
>   to inform the EL3 firmware of the request.
> * power domains can and are fed by a regulator rail and therefore
>   regulator control needed be implemented.
> 


Thank you for the patch. My tree is currently closed for new features
till the end of the merge window. I will review and/or apply the patch
then. If I misjudged this patch and this is a fix, please let me know.


Best regards,
Krzysztof

Re: [PATCH v4 10/10] pmdomain: samsung: implement domain-supply regulator

[André Draszik]

On Wed, 2026-01-28 at 16:10 +0000, André Draszik wrote:
> Some power domains on Exynos are fed by a regulator rail and therefore
> regulator control needs be implemented for Exynos power domains.
> 
> On Google gs101, HSI0 (USB) is one example of such a power domain.
> 
> While at it, add a to_exynos_pd() to avoid direct use of
> container_of() in various additional places, and update existing code
> to use it.
> 
> Signed-off-by: André Draszik <andre.draszik@linaro.org>
> ---
>  drivers/pmdomain/samsung/exynos-pm-domains.c | 53 +++++++++++++++++++++++++---
>  1 file changed, 48 insertions(+), 5 deletions(-)

Looks like I forgot to include the binding patch for this, will
do a v5 shortly.

Cheers,
Andre'

Re: [PATCH v4 01/10] dt-bindings: soc: google: add google,gs101-dtzpc

[Rob Herring]

On Wed, Jan 28, 2026 at 04:10:50PM +0000, André Draszik wrote:
> The Exynos Distributed TruztZone Protection Control (D_TZPC) provides
> an interface to the protection bits that are included in the TrustZone
> design in a secure system. It configures each area of the memory as
> secure or non-secure.

This sounds like what access-controllers binding is for. Does that work 
here?

> Signed-off-by: André Draszik <andre.draszik@linaro.org>
> ---
>  .../bindings/soc/google/google,gs101-dtzpc.yaml    | 42 ++++++++++++++++++++++
>  MAINTAINERS                                        |  1 +
>  2 files changed, 43 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/soc/google/google,gs101-dtzpc.yaml b/Documentation/devicetree/bindings/soc/google/google,gs101-dtzpc.yaml
> new file mode 100644
> index 0000000000000000000000000000000000000000..a8c61ce069d6910c47753bf14a792eb58e6ae182
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/soc/google/google,gs101-dtzpc.yaml
> @@ -0,0 +1,42 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/soc/google/google,gs101-dtzpc.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Samsung Exynos Distributed TruztZone Protection Control.
> +
> +description:
> +  Distributed TrustZone Protection Control (D_TZPC) provides an interface to the
> +  protection bits that are included in the TrustZone design in a secure system.
> +  It configures each area of the memory as secure or non-secure.
> +
> +maintainers:
> +  - André Draszik <andre.draszik@linaro.org>
> +
> +properties:
> +  compatible:
> +    const: google,gs101-dtzpc
> +
> +  clocks:
> +    maxItems: 1
> +
> +  reg:
> +    maxItems: 1
> +
> +required:
> +  - compatible
> +  - clocks
> +  - reg
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/clock/google,gs101.h>
> +
> +    dtzpc_hsi0: dtzpc@11010000 {
> +      compatible = "google,gs101-dtzpc";
> +      reg = <0x11010000 0x10000>;
> +      clocks = <&cmu_hsi0 CLK_GOUT_HSI0_D_TZPC_HSI0_PCLK>;
> +    };
> diff --git a/MAINTAINERS b/MAINTAINERS
> index a56f8f00aebb938aa765a8a6d66dfeb7f062dac8..98b2ef47c809ac0232e6941c9483b19d7c798bb4 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -10833,6 +10833,7 @@ P:	Documentation/process/maintainer-soc-clean-dts.rst
>  C:	irc://irc.oftc.net/pixel6-kernel-dev
>  F:	Documentation/devicetree/bindings/clock/google,gs101-clock.yaml
>  F:	Documentation/devicetree/bindings/phy/google,lga-usb-phy.yaml
> +F:	Documentation/devicetree/bindings/soc/google/google,gs101-dtzpc.yaml
>  F:	Documentation/devicetree/bindings/soc/google/google,gs101-pmu-intr-gen.yaml
>  F:	Documentation/devicetree/bindings/usb/google,lga-dwc3.yaml
>  F:	arch/arm64/boot/dts/exynos/google/
> 
> -- 
> 2.52.0.457.g6b5491de43-goog
> 

Re: [PATCH v4 01/10] dt-bindings: soc: google: add google,gs101-dtzpc

[André Draszik]

Hi Rob,

On Thu, 2026-01-29 at 10:55 -0600, Rob Herring wrote:
> On Wed, Jan 28, 2026 at 04:10:50PM +0000, André Draszik wrote:
> > The Exynos Distributed TruztZone Protection Control (D_TZPC) provides
> > an interface to the protection bits that are included in the TrustZone
> > design in a secure system. It configures each area of the memory as
> > secure or non-secure.
> 
> This sounds like what access-controllers binding is for. Does that work 
> here?

Thank you for the pointer, and yes, I did consider it, but decided against
it in the end for the following reasons:

* downstream drivers don't actually do much with this, it's only used to
  issue a request to the firmware to save / restore the configuration
  when power domains are turned off / on (via SMC call). There is no
  actual configuration happening unlike e.g. the drivers/bus/stm32_*
  case. Configuration etc. seems to be handled statically in the firmware
  in my case.

* therefore I didn't write an actual driver for this compatible and my
  patches are proposing to simply issue the SMC from the power domain
  driver in the respective paths.
  What I observed without having a driver matching the compatible, Linux
  will defer binding of consumer drivers (power domain via phandle in my
  case) until the access controller driver has bound. Since no such driver
  exists in my case, Linux keeps deferring the binding of my power domain
  driver forever, meaning it doesn't probe.

Maybe this restriction could be loosened for cases like this instead. Or
maybe I do need to write a dtzpc driver with the only purpose to issue the
SMC calls at the right time. Having such a driver seemed like overkill,
though.

I realise not using access-controller in DT looks like working-around an
issue in the kernel, but due to the minimal interaction from the Linux-side
I was hoping for that to be OK.

What do you think?


Cheers,
Andre'

> 
> > Signed-off-by: André Draszik <andre.draszik@linaro.org>
> > ---
> >  .../bindings/soc/google/google,gs101-dtzpc.yaml    | 42 ++++++++++++++++++++++
> >  MAINTAINERS                                        |  1 +
> >  2 files changed, 43 insertions(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/soc/google/google,gs101-dtzpc.yaml
> > b/Documentation/devicetree/bindings/soc/google/google,gs101-dtzpc.yaml
> > new file mode 100644
> > index 0000000000000000000000000000000000000000..a8c61ce069d6910c47753bf14a792eb58e6ae182
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/soc/google/google,gs101-dtzpc.yaml
> > @@ -0,0 +1,42 @@
> > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/soc/google/google,gs101-dtzpc.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Samsung Exynos Distributed TruztZone Protection Control.
> > +
> > +description:
> > +  Distributed TrustZone Protection Control (D_TZPC) provides an interface to the
> > +  protection bits that are included in the TrustZone design in a secure system.
> > +  It configures each area of the memory as secure or non-secure.
> > +
> > +maintainers:
> > +  - André Draszik <andre.draszik@linaro.org>
> > +
> > +properties:
> > +  compatible:
> > +    const: google,gs101-dtzpc
> > +
> > +  clocks:
> > +    maxItems: 1
> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +required:
> > +  - compatible
> > +  - clocks
> > +  - reg
> > +
> > +additionalProperties: false
> > +
> > +examples:
> > +  - |
> > +    #include <dt-bindings/clock/google,gs101.h>
> > +
> > +    dtzpc_hsi0: dtzpc@11010000 {
> > +      compatible = "google,gs101-dtzpc";
> > +      reg = <0x11010000 0x10000>;
> > +      clocks = <&cmu_hsi0 CLK_GOUT_HSI0_D_TZPC_HSI0_PCLK>;
> > +    };
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index a56f8f00aebb938aa765a8a6d66dfeb7f062dac8..98b2ef47c809ac0232e6941c9483b19d7c798bb4 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -10833,6 +10833,7 @@ P:	Documentation/process/maintainer-soc-clean-dts.rst
> >  C:	irc://irc.oftc.net/pixel6-kernel-dev
> >  F:	Documentation/devicetree/bindings/clock/google,gs101-clock.yaml
> >  F:	Documentation/devicetree/bindings/phy/google,lga-usb-phy.yaml
> > +F:	Documentation/devicetree/bindings/soc/google/google,gs101-dtzpc.yaml
> >  F:	Documentation/devicetree/bindings/soc/google/google,gs101-pmu-intr-gen.yaml
> >  F:	Documentation/devicetree/bindings/usb/google,lga-dwc3.yaml
> >  F:	arch/arm64/boot/dts/exynos/google/
> > 
> > -- 
> > 2.52.0.457.g6b5491de43-goog
> > 

Re: [PATCH v4 00/10] pmdomain: samsung: add support for Google GS101

[Ulf Hansson]

On Wed, 28 Jan 2026 at 17:10, André Draszik <andre.draszik@linaro.org> wrote:
>
> Hi,
>
> This series adds support for the power domains on Google GS101.
>
> There are a few differences compared to SoCs already supported by this
> driver:
> * register access does not work via plain ioremap() / readl() /
>   writel().
>   Instead, the regmap created by the PMU driver must be used (which
>   uses Arm SMCC calls under the hood).
> * DTZPC: a call needs to be made before and after power domain off/on,
>   to inform the EL3 firmware of the request.
> * power domains can and are fed by a regulator rail and therefore
>   regulator control needed be implemented.
>
> Bullet points 2 and 3 are new compared to previous versions of this
> series, and related changes are in patches 1, 2, 9, and 10. I can merge
> patch 9 (SMC call) into the gs101 patch (patch 7) if preferred, but for
> now I kept them independent to make it easier to see changes compared
> to previous versions of this series, and because patch 8 actually
> applies to not only gs101, but to many newer Exynos SoCs, and to make
> the two patches themselves easier to review and reason about.
>
> The DT update to add the new required properties on gs101 will be
> posted separately.
>
> Signed-off-by: André Draszik <andre.draszik@linaro.org>
> ---
> Changes in v4:
> - drop unneeded or already merged patches
> - drop patch "pmdomain: samsung: convert to regmap_read_poll_timeout()"
>   as Marek reported issues on some platforms
> - rebase
> - DTZPC related changes
> - Link to v3: https://lore.kernel.org/r/20251016-gs101-pd-v3-0-7b30797396e7@linaro.org
>
> Changes in v3:
> - use additionalProperties, not unevaluatedProperties in patch 2
> - fix path in $id in patch 2 (Rob)
> - drop comment around 'select' in patch 2 (Rob)
> - collect tags
> - Link to v2: https://lore.kernel.org/r/20251009-gs101-pd-v2-0-3f4a6db2af39@linaro.org
>
> Changes in v2:
> - Krzysztof:
>   - move google,gs101-pmu binding into separate file
>   - mark devm_kstrdup_const() patch as fix
>   - use bool for need_early_sync_state
>   - merge patches 8 and 10 from v1 series into one patch
> - collect tags
> - Link to v1: https://lore.kernel.org/r/20251006-gs101-pd-v1-0-f0cb0c01ea7b@linaro.org
>
> ---
> André Draszik (10):
>       dt-bindings: soc: google: add google,gs101-dtzpc
>       dt-bindings: power: samsung: add google,gs101-pd
>       dt-bindings: soc: samsung: exynos-pmu: move gs101-pmu into separate binding
>       dt-bindings: soc: google: gs101-pmu: allow power domains as children
>       pmdomain: samsung: convert to using regmap
>       pmdomain: samsung: don't hard-code offset for registers to 0 and 4
>       pmdomain: samsung: add support for google,gs101-pd
>       pmdomain: samsung: use dev_err() instead of pr_err()
>       pmdomain: samsung: implement SMC to save / restore TZ config
>       pmdomain: samsung: implement domain-supply regulator
>
>  .../devicetree/bindings/power/pd-samsung.yaml      |  29 ++-
>  .../bindings/soc/google/google,gs101-dtzpc.yaml    |  42 ++++
>  .../bindings/soc/google/google,gs101-pmu.yaml      |  97 ++++++++
>  .../bindings/soc/samsung/exynos-pmu.yaml           |  20 --
>  MAINTAINERS                                        |   2 +
>  drivers/pmdomain/samsung/exynos-pm-domains.c       | 254 ++++++++++++++++++---
>  6 files changed, 395 insertions(+), 49 deletions(-)
> ---
> base-commit: e3b32dcb9f23e3c3927ef3eec6a5842a988fb574
> change-id: 20251001-gs101-pd-d4dc97d70a84
>
> Best regards,
> --
> André Draszik <andre.draszik@linaro.org>
>

I have looked through the series and it looks good to me. I will be
awaiting a new version and to get the DT patches acked, before I
continue to apply patches.

Kind regards
Uffe