[PATCH v5 04/10] drivers: qcom: rpmh: add RPMH helper functions

Lina Iyer
2018-04-05T16:21:05Z

Sending RPMH requests and waiting for response from the controller
through a callback is common functionality across all platform drivers.
To simplify drivers, add a library functions to create RPMH client and
send resource state requests.

rpmh_write() is a synchronous blocking call that can be used to send
active state requests.

Signed-off-by: Lina Iyer <ilina@codeaurora.org>
---

Changes in v4:
- use const struct tcs_cmd in API
- remove wait count from this patch
- changed -EFAULT to -EINVAL
---
drivers/soc/qcom/Makefile | 4 +-
drivers/soc/qcom/rpmh-internal.h | 2 +
drivers/soc/qcom/rpmh-rsc.c | 7 ++
drivers/soc/qcom/rpmh.c | 253 +++++++++++++++++++++++++++++++++++++++
include/soc/qcom/rpmh.h | 34 ++++++
5 files changed, 299 insertions(+), 1 deletion(-)
create mode 100644 drivers/soc/qcom/rpmh.c
create mode 100644 include/soc/qcom/rpmh.h

diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
index cb6300f6a8e9..bb395c3202ca 100644
--- a/drivers/soc/qcom/Makefile
+++ b/drivers/soc/qcom/Makefile
@@ -7,7 +7,9 @@ obj-$(CONFIG_QCOM_PM) += spm.o
obj-$(CONFIG_QCOM_QMI_HELPERS) += qmi_helpers.o
qmi_helpers-y += qmi_encdec.o qmi_interface.o
obj-$(CONFIG_QCOM_RMTFS_MEM) += rmtfs_mem.o
-obj-$(CONFIG_QCOM_RPMH) += rpmh-rsc.o
+obj-$(CONFIG_QCOM_RPMH) += qcom_rpmh.o
+qcom_rpmh-y += rpmh-rsc.o
+qcom_rpmh-y += rpmh.o
obj-$(CONFIG_QCOM_SMD_RPM) += smd-rpm.o
obj-$(CONFIG_QCOM_SMEM) += smem.o
obj-$(CONFIG_QCOM_SMEM_STATE) += smem_state.o
diff --git a/drivers/soc/qcom/rpmh-internal.h b/drivers/soc/qcom/rpmh-internal.h
index aa73ec4b3e42..125f9faec536 100644
--- a/drivers/soc/qcom/rpmh-internal.h
+++ b/drivers/soc/qcom/rpmh-internal.h
@@ -86,4 +86,6 @@ struct rsc_drv {

int rpmh_rsc_send_data(struct rsc_drv *drv, const struct tcs_request *msg);

+void rpmh_tx_done(const struct tcs_request *msg, int r);
+
#endif /* __RPM_INTERNAL_H__ */
diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c
index f604101a4fc2..c5cde917dba6 100644
--- a/drivers/soc/qcom/rpmh-rsc.c
+++ b/drivers/soc/qcom/rpmh-rsc.c
@@ -252,6 +252,8 @@ static void tcs_notify_tx_done(unsigned long data)
struct rsc_drv *drv = (struct rsc_drv *)data;
struct tcs_response *resp;
unsigned long flags;
+ const struct tcs_request *msg;
+ int err;

for (;;) {
spin_lock_irqsave(&drv->drv_lock, flags);
@@ -264,7 +266,10 @@ static void tcs_notify_tx_done(unsigned long data)
list_del(&resp->list);
spin_unlock_irqrestore(&drv->drv_lock, flags);
trace_rpmh_notify_tx_done(drv, resp);
+ msg = resp->msg;
+ err = resp->err;
free_response(resp);
+ rpmh_tx_done(msg, err);
}
}

@@ -554,6 +559,8 @@ static int rpmh_rsc_probe(struct platform_device *pdev)
/* Enable the active TCS to send requests immediately */
write_tcs_reg(drv, RSC_DRV_IRQ_ENABLE, 0, 0, drv->tcs[ACTIVE_TCS].mask);

+ dev_set_drvdata(&pdev->dev, drv);
+
return devm_of_platform_populate(&pdev->dev);
}

diff --git a/drivers/soc/qcom/rpmh.c b/drivers/soc/qcom/rpmh.c
new file mode 100644
index 000000000000..e3c7491e7baf
--- /dev/null
+++ b/drivers/soc/qcom/rpmh.c
@@ -0,0 +1,253 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2016-2018, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/atomic.h>
+#include <linux/interrupt.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/mailbox_client.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/wait.h>
+
+#include <soc/qcom/rpmh.h>
+
+#include "rpmh-internal.h"
+
+#define RPMH_MAX_MBOXES 2
+#define RPMH_TIMEOUT_MS 10000
+
+#define DEFINE_RPMH_MSG_ONSTACK(rc, s, q, name) \
+ struct rpmh_request name = { \
+ .msg = { \
+ .state = s, \
+ .cmds = name.cmd, \
+ .num_cmds = 0, \
+ .wait_for_compl = true, \
+ }, \
+ .cmd = { { 0 } }, \
+ .completion = q, \
+ .rc = rc, \
+ }
+
+/**
+ * struct rpmh_request: the message to be sent to rpmh-rsc
+ *
+ * @msg: the request
+ * @cmd: the payload that will be part of the @msg
+ * @completion: triggered when request is done
+ * @err: err return from the controller
+ */
+struct rpmh_request {
+ struct tcs_request msg;
+ struct tcs_cmd cmd[MAX_RPMH_PAYLOAD];
+ struct completion *completion;
+ struct rpmh_client *rc;
+ int err;
+};
+
+/**
+ * struct rpmh_ctrlr: our representation of the controller
+ *
+ * @drv: the controller instance
+ */
+struct rpmh_ctrlr {
+ struct rsc_drv *drv;
+};
+
+/**
+ * struct rpmh_client: the client object
+ *
+ * @dev: the platform device that is the owner
+ * @ctrlr: the controller associated with this client.
+ */
+struct rpmh_client {
+ struct device *dev;
+ struct rpmh_ctrlr *ctrlr;
+};
+
+static struct rpmh_ctrlr rpmh_rsc[RPMH_MAX_MBOXES];
+static DEFINE_MUTEX(rpmh_ctrlr_mutex);
+
+void rpmh_tx_done(const struct tcs_request *msg, int r)
+{
+ struct rpmh_request *rpm_msg = container_of(msg, struct rpmh_request,
+ msg);
+ struct completion *compl = rpm_msg->completion;
+
+ rpm_msg->err = r;
+
+ if (r)
+ dev_err(rpm_msg->rc->dev,
+ "RPMH TX fail in msg addr=%#x, err=%d\n",
+ rpm_msg->msg.cmds[0].addr, r);
+
+ /* Signal the blocking thread we are done */
+ if (compl)
+ complete(compl);
+}
+EXPORT_SYMBOL(rpmh_tx_done);
+
+/**
+ * wait_for_tx_done: Wait until the response is received.
+ *
+ * @rc: The RPMH client
+ * @compl: The completion object
+ * @addr: An addr that we sent in that request
+ * @data: The data for the address in that request
+ */
+static int wait_for_tx_done(struct rpmh_client *rc,
+ struct completion *compl, u32 addr, u32 data)
+{
+ int ret;
+
+ might_sleep();
+
+ ret = wait_for_completion_timeout(compl,
+ msecs_to_jiffies(RPMH_TIMEOUT_MS));
+ if (ret)
+ dev_dbg(rc->dev,
+ "RPMH response received addr=%#x data=%#x\n",
+ addr, data);
+ else
+ dev_err(rc->dev,
+ "RPMH response timeout addr=%#x data=%#x\n",
+ addr, data);
+
+ return (ret > 0) ? 0 : -ETIMEDOUT;
+}
+
+/**
+ * __rpmh_write: send the RPMH request
+ *
+ * @rc: The RPMH client
+ * @state: Active/Sleep request type
+ * @rpm_msg: The data that needs to be sent (cmds).
+ */
+static int __rpmh_write(struct rpmh_client *rc, enum rpmh_state state,
+ struct rpmh_request *rpm_msg)
+{
+ int ret = -EINVAL;
+
+ rpm_msg->msg.state = state;
+
+ if (state == RPMH_ACTIVE_ONLY_STATE) {
+ WARN_ON(irqs_disabled());
+ ret = rpmh_rsc_send_data(rc->ctrlr->drv, &rpm_msg->msg);
+ if (!ret)
+ dev_dbg(rc->dev,
+ "RPMH request sent addr=%#x, data=%i#x\n",
+ rpm_msg->msg.cmds[0].addr,
+ rpm_msg->msg.cmds[0].data);
+ else
+ dev_warn(rc->dev,
+ "Error in RPMH request addr=%#x, data=%#x\n",
+ rpm_msg->msg.cmds[0].addr,
+ rpm_msg->msg.cmds[0].data);
+ }
+
+ return ret;
+}
+
+/**
+ * rpmh_write: Write a set of RPMH commands and block until response
+ *
+ * @rc: The RPMh handle got from rpmh_get_client
+ * @state: Active/sleep set
+ * @cmd: The payload data
+ * @n: The number of elements in @cmd
+ *
+ * May sleep. Do not call from atomic contexts.
+ */
+int rpmh_write(struct rpmh_client *rc, enum rpmh_state state,
+ const struct tcs_cmd *cmd, u32 n)
+{
+ DECLARE_COMPLETION_ONSTACK(compl);
+ DEFINE_RPMH_MSG_ONSTACK(rc, state, &compl, rpm_msg);
+ int ret;
+
+ if (IS_ERR_OR_NULL(rc) || !cmd || !n || n > MAX_RPMH_PAYLOAD)
+ return -EINVAL;
+
+ memcpy(rpm_msg.cmd, cmd, n * sizeof(*cmd));
+ rpm_msg.msg.num_cmds = n;
+
+ ret = __rpmh_write(rc, state, &rpm_msg);
+ if (ret)
+ return ret;
+
+ return wait_for_tx_done(rc, &compl, cmd[0].addr, cmd[0].data);
+}
+EXPORT_SYMBOL(rpmh_write);
+
+static struct rpmh_ctrlr *get_rpmh_ctrlr(struct platform_device *pdev)
+{
+ int i;
+ struct rsc_drv *drv = dev_get_drvdata(pdev->dev.parent);
+ struct rpmh_ctrlr *ctrlr = ERR_PTR(-EINVAL);
+
+ if (!drv)
+ return ctrlr;
+
+ mutex_lock(&rpmh_ctrlr_mutex);
+ for (i = 0; i < RPMH_MAX_MBOXES; i++) {
+ if (rpmh_rsc[i].drv == drv) {
+ ctrlr = &rpmh_rsc[i];
+ goto unlock;
+ }
+ }
+
+ for (i = 0; i < RPMH_MAX_MBOXES; i++) {
+ if (rpmh_rsc[i].drv == NULL) {
+ ctrlr = &rpmh_rsc[i];
+ ctrlr->drv = drv;
+ break;
+ }
+ }
+ WARN_ON(i == RPMH_MAX_MBOXES);
+unlock:
+ mutex_unlock(&rpmh_ctrlr_mutex);
+ return ctrlr;
+}
+
+/**
+ * rpmh_get_client: Get the RPMh handle
+ *
+ * @pdev: the platform device which needs to communicate with RPM
+ * accelerators
+ * May sleep.
+ */
+struct rpmh_client *rpmh_get_client(struct platform_device *pdev)
+{
+ struct rpmh_client *rc;
+
+ rc = kzalloc(sizeof(*rc), GFP_KERNEL);
+ if (!rc)
+ return ERR_PTR(-ENOMEM);
+
+ rc->dev = &pdev->dev;
+ rc->ctrlr = get_rpmh_ctrlr(pdev);
+ if (IS_ERR(rc->ctrlr)) {
+ kfree(rc);
+ return ERR_PTR(-EINVAL);
+ }
+
+ return rc;
+}
+EXPORT_SYMBOL(rpmh_get_client);
+
+/**
+ * rpmh_release: Release the RPMH client
+ *
+ * @rc: The RPMh handle to be freed.
+ */
+void rpmh_release(struct rpmh_client *rc)
+{
+ kfree(rc);
+}
+EXPORT_SYMBOL(rpmh_release);
diff --git a/include/soc/qcom/rpmh.h b/include/soc/qcom/rpmh.h
new file mode 100644
index 000000000000..95334d4c1ede
--- /dev/null
+++ b/include/soc/qcom/rpmh.h
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2016-2018, The Linux Foundation. All rights reserved.
+ */
+
+#ifndef __SOC_QCOM_RPMH_H__
+#define __SOC_QCOM_RPMH_H__
+
+#include <soc/qcom/tcs.h>
+#include <linux/platform_device.h>
+
+struct rpmh_client;
+
+#if IS_ENABLED(CONFIG_QCOM_RPMH)
+int rpmh_write(struct rpmh_client *rc, enum rpmh_state state,
+ const struct tcs_cmd *cmd, u32 n);
+
+struct rpmh_client *rpmh_get_client(struct platform_device *pdev);
+
+void rpmh_release(struct rpmh_client *rc);
+
+#else
+
+static inline int rpmh_write(struct rpmh_client *rc, enum rpmh_state state,
+ const struct tcs_cmd *cmd, u32 n)
+{ return -ENODEV; }
+
+static inline struct rpmh_client *rpmh_get_client(struct platform_device *pdev)
+{ return ERR_PTR(-ENODEV); }
+
+static inline void rpmh_release(struct rpmh_client *rc) { }
+#endif /* CONFIG_QCOM_RPMH */
+
+#endif /* __SOC_QCOM_RPMH_H__ */
--
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