[PATCH 0/3] net: ipa: backport for v5.15.y

[PATCH 0/3] net: ipa: backport for v5.15.y

[Alex Elder]

This series is a back-port for stable branch version 5.15 *only*.
The IPA patches have already been applied to v5.16.y, and they are
not required for versions prior to 5.15.

There was a missing prerequisite commit that prevented building the
code successfully when back-porting to v5.15 was first attempted.
That commit has been added to the front of this series.  All three
commits otherwise cherry-pick cleanly.

					-Alex

Alex Elder (2):
  dt-bindings: net: qcom,ipa: add optional qcom,qmp property
  net: ipa: request IPA register values be retained

Deepak Kumar Singh (1):
  soc: qcom: aoss: Expose send for generic usecase

 .../devicetree/bindings/net/qcom,ipa.yaml     |  6 +++
 drivers/net/ipa/ipa_power.c                   | 52 ++++++++++++++++++
 drivers/net/ipa/ipa_power.h                   |  7 +++
 drivers/net/ipa/ipa_uc.c                      |  5 ++
 drivers/soc/qcom/qcom_aoss.c                  | 54 ++++++++++++++++++-
 include/linux/soc/qcom/qcom_aoss.h            | 38 +++++++++++++
 6 files changed, 161 insertions(+), 1 deletion(-)
 create mode 100644 include/linux/soc/qcom/qcom_aoss.h

-- 
2.32.0

[PATCH 1/3] soc: qcom: aoss: Expose send for generic usecase

[Alex Elder]

From: Deepak Kumar Singh <deesin@codeaurora.org>

commit 8c75d585b931ac874fbe4ee5a8f1811d20c2817f upstream.

Not all upcoming usecases will have an interface to allow the aoss
driver to hook onto. Expose the send api and create a get function to
enable drivers to send their own messages to aoss.

Signed-off-by: Chris Lew <clew@codeaurora.org>
Signed-off-by: Deepak Kumar Singh <deesin@codeaurora.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/1630420228-31075-2-git-send-email-deesin@codeaurora.org
---
 drivers/soc/qcom/qcom_aoss.c       | 54 +++++++++++++++++++++++++++++-
 include/linux/soc/qcom/qcom_aoss.h | 38 +++++++++++++++++++++
 2 files changed, 91 insertions(+), 1 deletion(-)
 create mode 100644 include/linux/soc/qcom/qcom_aoss.h

diff --git a/drivers/soc/qcom/qcom_aoss.c b/drivers/soc/qcom/qcom_aoss.c
index a0659cf278456..d40d8e20ceb46 100644
--- a/drivers/soc/qcom/qcom_aoss.c
+++ b/drivers/soc/qcom/qcom_aoss.c
@@ -8,10 +8,12 @@
 #include <linux/io.h>
 #include <linux/mailbox_client.h>
 #include <linux/module.h>
+#include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/pm_domain.h>
 #include <linux/thermal.h>
 #include <linux/slab.h>
+#include <linux/soc/qcom/qcom_aoss.h>
 
 #define QMP_DESC_MAGIC			0x0
 #define QMP_DESC_VERSION		0x4
@@ -223,11 +225,14 @@ static bool qmp_message_empty(struct qmp *qmp)
  *
  * Return: 0 on success, negative errno on failure
  */
-static int qmp_send(struct qmp *qmp, const void *data, size_t len)
+int qmp_send(struct qmp *qmp, const void *data, size_t len)
 {
 	long time_left;
 	int ret;
 
+	if (WARN_ON(IS_ERR_OR_NULL(qmp) || !data))
+		return -EINVAL;
+
 	if (WARN_ON(len + sizeof(u32) > qmp->size))
 		return -EINVAL;
 
@@ -261,6 +266,7 @@ static int qmp_send(struct qmp *qmp, const void *data, size_t len)
 
 	return ret;
 }
+EXPORT_SYMBOL(qmp_send);
 
 static int qmp_qdss_clk_prepare(struct clk_hw *hw)
 {
@@ -519,6 +525,51 @@ static void qmp_cooling_devices_remove(struct qmp *qmp)
 		thermal_cooling_device_unregister(qmp->cooling_devs[i].cdev);
 }
 
+/**
+ * qmp_get() - get a qmp handle from a device
+ * @dev: client device pointer
+ *
+ * Return: handle to qmp device on success, ERR_PTR() on failure
+ */
+struct qmp *qmp_get(struct device *dev)
+{
+	struct platform_device *pdev;
+	struct device_node *np;
+	struct qmp *qmp;
+
+	if (!dev || !dev->of_node)
+		return ERR_PTR(-EINVAL);
+
+	np = of_parse_phandle(dev->of_node, "qcom,qmp", 0);
+	if (!np)
+		return ERR_PTR(-ENODEV);
+
+	pdev = of_find_device_by_node(np);
+	of_node_put(np);
+	if (!pdev)
+		return ERR_PTR(-EINVAL);
+
+	qmp = platform_get_drvdata(pdev);
+
+	return qmp ? qmp : ERR_PTR(-EPROBE_DEFER);
+}
+EXPORT_SYMBOL(qmp_get);
+
+/**
+ * qmp_put() - release a qmp handle
+ * @qmp: qmp handle obtained from qmp_get()
+ */
+void qmp_put(struct qmp *qmp)
+{
+	/*
+	 * Match get_device() inside of_find_device_by_node() in
+	 * qmp_get()
+	 */
+	if (!IS_ERR_OR_NULL(qmp))
+		put_device(qmp->dev);
+}
+EXPORT_SYMBOL(qmp_put);
+
 static int qmp_probe(struct platform_device *pdev)
 {
 	struct resource *res;
@@ -615,6 +666,7 @@ static struct platform_driver qmp_driver = {
 	.driver = {
 		.name		= "qcom_aoss_qmp",
 		.of_match_table	= qmp_dt_match,
+		.suppress_bind_attrs = true,
 	},
 	.probe = qmp_probe,
 	.remove	= qmp_remove,
diff --git a/include/linux/soc/qcom/qcom_aoss.h b/include/linux/soc/qcom/qcom_aoss.h
new file mode 100644
index 0000000000000..3c2a82e606f81
--- /dev/null
+++ b/include/linux/soc/qcom/qcom_aoss.h
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2021, The Linux Foundation. All rights reserved.
+ */
+
+#ifndef __QCOM_AOSS_H__
+#define __QCOM_AOSS_H__
+
+#include <linux/err.h>
+#include <linux/device.h>
+
+struct qmp;
+
+#if IS_ENABLED(CONFIG_QCOM_AOSS_QMP)
+
+int qmp_send(struct qmp *qmp, const void *data, size_t len);
+struct qmp *qmp_get(struct device *dev);
+void qmp_put(struct qmp *qmp);
+
+#else
+
+static inline int qmp_send(struct qmp *qmp, const void *data, size_t len)
+{
+	return -ENODEV;
+}
+
+static inline struct qmp *qmp_get(struct device *dev)
+{
+	return ERR_PTR(-ENODEV);
+}
+
+static inline void qmp_put(struct qmp *qmp)
+{
+}
+
+#endif
+
+#endif
-- 
2.32.0

[PATCH 2/3] dt-bindings: net: qcom,ipa: add optional qcom,qmp property

[Alex Elder]

commit ac62a0174d62ae0f4447c0c8cf35a8e5d793df56 upstream.

For some systems, the IPA driver must make a request to ensure that
its registers are retained across power collapse of the IPA hardware.
On such systems, we'll use the existence of the "qcom,qmp" property
as a signal that this request is required.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 Documentation/devicetree/bindings/net/qcom,ipa.yaml | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/qcom,ipa.yaml b/Documentation/devicetree/bindings/net/qcom,ipa.yaml
index b8a0b392b24ea..c52ec1ee7df6e 100644
--- a/Documentation/devicetree/bindings/net/qcom,ipa.yaml
+++ b/Documentation/devicetree/bindings/net/qcom,ipa.yaml
@@ -106,6 +106,10 @@ properties:
           - const: imem
           - const: config
 
+  qcom,qmp:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description: phandle to the AOSS side-channel message RAM
+
   qcom,smem-states:
     $ref: /schemas/types.yaml#/definitions/phandle-array
     description: State bits used in by the AP to signal the modem.
@@ -221,6 +225,8 @@ examples:
                                      "imem",
                                      "config";
 
+                qcom,qmp = <&aoss_qmp>;
+
                 qcom,smem-states = <&ipa_smp2p_out 0>,
                                    <&ipa_smp2p_out 1>;
                 qcom,smem-state-names = "ipa-clock-enabled-valid",
-- 
2.32.0

[PATCH 3/3] net: ipa: request IPA register values be retained

[Alex Elder]

commit 34a081761e4e3c35381cbfad609ebae2962fe2f8 upstream.

In some cases, the IPA hardware needs to request the always-on
subsystem (AOSS) to coordinate with the IPA microcontroller to
retain IPA register values at power collapse.  This is done by
issuing a QMP request to the AOSS microcontroller.  A similar
request ondoes that request.

We must get and hold the "QMP" handle early, because we might get
back EPROBE_DEFER for that.  But the actual request should be sent
while we know the IPA clock is active, and when we know the
microcontroller is operational.

Fixes: 1aac309d3207 ("net: ipa: use autosuspend")
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 drivers/net/ipa/ipa_power.c | 52 +++++++++++++++++++++++++++++++++++++
 drivers/net/ipa/ipa_power.h |  7 +++++
 drivers/net/ipa/ipa_uc.c    |  5 ++++
 3 files changed, 64 insertions(+)

diff --git a/drivers/net/ipa/ipa_power.c b/drivers/net/ipa/ipa_power.c
index b1c6c0fcb654f..f2989aac47a62 100644
--- a/drivers/net/ipa/ipa_power.c
+++ b/drivers/net/ipa/ipa_power.c
@@ -11,6 +11,8 @@
 #include <linux/pm_runtime.h>
 #include <linux/bitops.h>
 
+#include "linux/soc/qcom/qcom_aoss.h"
+
 #include "ipa.h"
 #include "ipa_power.h"
 #include "ipa_endpoint.h"
@@ -64,6 +66,7 @@ enum ipa_power_flag {
  * struct ipa_power - IPA power management information
  * @dev:		IPA device pointer
  * @core:		IPA core clock
+ * @qmp:		QMP handle for AOSS communication
  * @spinlock:		Protects modem TX queue enable/disable
  * @flags:		Boolean state flags
  * @interconnect_count:	Number of elements in interconnect[]
@@ -72,6 +75,7 @@ enum ipa_power_flag {
 struct ipa_power {
 	struct device *dev;
 	struct clk *core;
+	struct qmp *qmp;
 	spinlock_t spinlock;	/* used with STOPPED/STARTED power flags */
 	DECLARE_BITMAP(flags, IPA_POWER_FLAG_COUNT);
 	u32 interconnect_count;
@@ -382,6 +386,47 @@ void ipa_power_modem_queue_active(struct ipa *ipa)
 	clear_bit(IPA_POWER_FLAG_STARTED, ipa->power->flags);
 }
 
+static int ipa_power_retention_init(struct ipa_power *power)
+{
+	struct qmp *qmp = qmp_get(power->dev);
+
+	if (IS_ERR(qmp)) {
+		if (PTR_ERR(qmp) == -EPROBE_DEFER)
+			return -EPROBE_DEFER;
+
+		/* We assume any other error means it's not defined/needed */
+		qmp = NULL;
+	}
+	power->qmp = qmp;
+
+	return 0;
+}
+
+static void ipa_power_retention_exit(struct ipa_power *power)
+{
+	qmp_put(power->qmp);
+	power->qmp = NULL;
+}
+
+/* Control register retention on power collapse */
+void ipa_power_retention(struct ipa *ipa, bool enable)
+{
+	static const char fmt[] = "{ class: bcm, res: ipa_pc, val: %c }";
+	struct ipa_power *power = ipa->power;
+	char buf[36];	/* Exactly enough for fmt[]; size a multiple of 4 */
+	int ret;
+
+	if (!power->qmp)
+		return;		/* Not needed on this platform */
+
+	(void)snprintf(buf, sizeof(buf), fmt, enable ? '1' : '0');
+
+	ret = qmp_send(power->qmp, buf, sizeof(buf));
+	if (ret)
+		dev_err(power->dev, "error %d sending QMP %sable request\n",
+			ret, enable ? "en" : "dis");
+}
+
 int ipa_power_setup(struct ipa *ipa)
 {
 	int ret;
@@ -438,12 +483,18 @@ ipa_power_init(struct device *dev, const struct ipa_power_data *data)
 	if (ret)
 		goto err_kfree;
 
+	ret = ipa_power_retention_init(power);
+	if (ret)
+		goto err_interconnect_exit;
+
 	pm_runtime_set_autosuspend_delay(dev, IPA_AUTOSUSPEND_DELAY);
 	pm_runtime_use_autosuspend(dev);
 	pm_runtime_enable(dev);
 
 	return power;
 
+err_interconnect_exit:
+	ipa_interconnect_exit(power);
 err_kfree:
 	kfree(power);
 err_clk_put:
@@ -460,6 +511,7 @@ void ipa_power_exit(struct ipa_power *power)
 
 	pm_runtime_disable(dev);
 	pm_runtime_dont_use_autosuspend(dev);
+	ipa_power_retention_exit(power);
 	ipa_interconnect_exit(power);
 	kfree(power);
 	clk_put(clk);
diff --git a/drivers/net/ipa/ipa_power.h b/drivers/net/ipa/ipa_power.h
index 2151805d7fbb0..6f84f057a2095 100644
--- a/drivers/net/ipa/ipa_power.h
+++ b/drivers/net/ipa/ipa_power.h
@@ -40,6 +40,13 @@ void ipa_power_modem_queue_wake(struct ipa *ipa);
  */
 void ipa_power_modem_queue_active(struct ipa *ipa);
 
+/**
+ * ipa_power_retention() - Control register retention on power collapse
+ * @ipa:	IPA pointer
+ * @enable:	Whether retention should be enabled or disabled
+ */
+void ipa_power_retention(struct ipa *ipa, bool enable);
+
 /**
  * ipa_power_setup() - Set up IPA power management
  * @ipa:	IPA pointer
diff --git a/drivers/net/ipa/ipa_uc.c b/drivers/net/ipa/ipa_uc.c
index 856e55a080a7f..fe11910518d95 100644
--- a/drivers/net/ipa/ipa_uc.c
+++ b/drivers/net/ipa/ipa_uc.c
@@ -11,6 +11,7 @@
 
 #include "ipa.h"
 #include "ipa_uc.h"
+#include "ipa_power.h"
 
 /**
  * DOC:  The IPA embedded microcontroller
@@ -154,6 +155,7 @@ static void ipa_uc_response_hdlr(struct ipa *ipa, enum ipa_irq_id irq_id)
 	case IPA_UC_RESPONSE_INIT_COMPLETED:
 		if (ipa->uc_powered) {
 			ipa->uc_loaded = true;
+			ipa_power_retention(ipa, true);
 			pm_runtime_mark_last_busy(dev);
 			(void)pm_runtime_put_autosuspend(dev);
 			ipa->uc_powered = false;
@@ -184,6 +186,9 @@ void ipa_uc_deconfig(struct ipa *ipa)
 
 	ipa_interrupt_remove(ipa->interrupt, IPA_IRQ_UC_1);
 	ipa_interrupt_remove(ipa->interrupt, IPA_IRQ_UC_0);
+	if (ipa->uc_loaded)
+		ipa_power_retention(ipa, false);
+
 	if (!ipa->uc_powered)
 		return;
 
-- 
2.32.0

Re: [PATCH 1/3] soc: qcom: aoss: Expose send for generic usecase

[Greg KH]

On Wed, Apr 13, 2022 at 09:48:09AM -0500, Alex Elder wrote:
> From: Deepak Kumar Singh <deesin@codeaurora.org>
> 
> commit 8c75d585b931ac874fbe4ee5a8f1811d20c2817f upstream.
> 
> Not all upcoming usecases will have an interface to allow the aoss
> driver to hook onto. Expose the send api and create a get function to
> enable drivers to send their own messages to aoss.
> 
> Signed-off-by: Chris Lew <clew@codeaurora.org>
> Signed-off-by: Deepak Kumar Singh <deesin@codeaurora.org>
> Reviewed-by: Stephen Boyd <swboyd@chromium.org>
> Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
> Link: https://lore.kernel.org/r/1630420228-31075-2-git-send-email-deesin@codeaurora.org

You sent this on, so you should also sign-off on it, right?

thanks,

greg k-h

Re: [PATCH 1/3] soc: qcom: aoss: Expose send for generic usecase

[Alex Elder]

On 4/14/22 6:00 AM, Greg KH wrote:
> On Wed, Apr 13, 2022 at 09:48:09AM -0500, Alex Elder wrote:
>> From: Deepak Kumar Singh <deesin@codeaurora.org>
>>
>> commit 8c75d585b931ac874fbe4ee5a8f1811d20c2817f upstream.
>>
>> Not all upcoming usecases will have an interface to allow the aoss
>> driver to hook onto. Expose the send api and create a get function to
>> enable drivers to send their own messages to aoss.
>>
>> Signed-off-by: Chris Lew <clew@codeaurora.org>
>> Signed-off-by: Deepak Kumar Singh <deesin@codeaurora.org>
>> Reviewed-by: Stephen Boyd <swboyd@chromium.org>
>> Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
>> Link: https://lore.kernel.org/r/1630420228-31075-2-git-send-email-deesin@codeaurora.org
> 
> You sent this on, so you should also sign-off on it, right?

Yes I should have, sorry.  I'll send v2 of the series.  Thanks.

					-Alex

> 
> thanks,
> 
> greg k-h