drivers: qcom: rpmh: add RPMH helper functions

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>
Signed-off-by: Raju P.L.S.S.S.N <rplsssn@codeaurora.org>
Signed-off-by: Andy Gross <andy.gross@linaro.org>

diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
index 036ecc4..f25b54c 100644 (file)
--- a/drivers/soc/qcom/Makefile
+++ b/drivers/soc/qcom/Makefile
@@ -9,7 +9,9 @@ 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 cc29176..1e687f7 100644 (file)
--- a/drivers/soc/qcom/rpmh-internal.h
+++ b/drivers/soc/qcom/rpmh-internal.h
@@ -42,6 +42,32 @@ struct tcs_group {
 };
 
 /**
+ * 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
+ * @dev: the device making the request
+ * @err: err return from the controller
+ */
+struct rpmh_request {
+       struct tcs_request msg;
+       struct tcs_cmd cmd[MAX_RPMH_PAYLOAD];
+       struct completion *completion;
+       const struct device *dev;
+       int err;
+};
+
+/**
+ * struct rpmh_ctrlr: our representation of the controller
+ *
+ * @drv: the controller instance
+ */
+struct rpmh_ctrlr {
+       struct rsc_drv *drv;
+};
+
+/**
  * struct rsc_drv: the Direct Resource Voter (DRV) of the
  * Resource State Coordinator controller (RSC)
  *
@@ -52,6 +78,7 @@ struct tcs_group {
  * @tcs:        TCS groups
  * @tcs_in_use: s/w state of the TCS
  * @lock:       synchronize state of the controller
+ * @client:     handle to the DRV's client.
  */
 struct rsc_drv {
        const char *name;
@@ -61,9 +88,11 @@ struct rsc_drv {
        struct tcs_group tcs[TCS_TYPE_NR];
        DECLARE_BITMAP(tcs_in_use, MAX_TCS_NR);
        spinlock_t lock;
+       struct rpmh_ctrlr client;
 };
 
-
 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 89d41cd..91f8d60 100644 (file)
--- a/drivers/soc/qcom/rpmh-rsc.c
+++ b/drivers/soc/qcom/rpmh-rsc.c
@@ -138,7 +138,7 @@ static const struct tcs_request *get_req_from_tcs(struct rsc_drv *drv,
 static irqreturn_t tcs_tx_done(int irq, void *p)
 {
        struct rsc_drv *drv = p;
-       int i, j, err;
+       int i, j, err = 0;
        unsigned long irq_status;
        const struct tcs_request *req;
        struct tcs_cmd *cmd;
@@ -175,6 +175,8 @@ skip:
                spin_lock(&drv->lock);
                clear_bit(i, drv->tcs_in_use);
                spin_unlock(&drv->lock);
+               if (req)
+                       rpmh_tx_done(req, err);
        }
 
        return IRQ_HANDLED;
@@ -467,6 +469,8 @@ 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, 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 (file)
index 0000000..5e022cb
--- /dev/null
+++ b/drivers/soc/qcom/rpmh.c
@@ -0,0 +1,116 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2016-2018, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/atomic.h>
+#include <linux/bug.h>
+#include <linux/interrupt.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.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_TIMEOUT_MS                        msecs_to_jiffies(10000)
+
+#define DEFINE_RPMH_MSG_ONSTACK(dev, s, q, name)       \
+       struct rpmh_request name = {                    \
+               .msg = {                                \
+                       .state = s,                     \
+                       .cmds = name.cmd,               \
+                       .num_cmds = 0,                  \
+                       .wait_for_compl = true,         \
+               },                                      \
+               .cmd = { { 0 } },                       \
+               .completion = q,                        \
+               .dev = dev,                             \
+       }
+
+#define ctrlr_to_drv(ctrlr) container_of(ctrlr, struct rsc_drv, client)
+
+static struct rpmh_ctrlr *get_rpmh_ctrlr(const struct device *dev)
+{
+       struct rsc_drv *drv = dev_get_drvdata(dev->parent);
+
+       return &drv->client;
+}
+
+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->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);
+}
+
+/**
+ * __rpmh_write: send the RPMH request
+ *
+ * @dev: The device making the request
+ * @state: Active/Sleep request type
+ * @rpm_msg: The data that needs to be sent (cmds).
+ */
+static int __rpmh_write(const struct device *dev, enum rpmh_state state,
+                       struct rpmh_request *rpm_msg)
+{
+       struct rpmh_ctrlr *ctrlr = get_rpmh_ctrlr(dev);
+
+       rpm_msg->msg.state = state;
+
+       if (state != RPMH_ACTIVE_ONLY_STATE)
+               return -EINVAL;
+
+       WARN_ON(irqs_disabled());
+
+       return rpmh_rsc_send_data(ctrlr_to_drv(ctrlr), &rpm_msg->msg);
+}
+
+/**
+ * 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(const struct device *dev, enum rpmh_state state,
+              const struct tcs_cmd *cmd, u32 n)
+{
+       DECLARE_COMPLETION_ONSTACK(compl);
+       DEFINE_RPMH_MSG_ONSTACK(dev, state, &compl, rpm_msg);
+       int ret;
+
+       if (!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(dev, state, &rpm_msg);
+       if (ret)
+               return ret;
+
+       ret = wait_for_completion_timeout(&compl, RPMH_TIMEOUT_MS);
+       WARN_ON(!ret);
+       return (ret > 0) ? 0 : -ETIMEDOUT;
+}
+EXPORT_SYMBOL(rpmh_write);

diff --git a/include/soc/qcom/rpmh.h b/include/soc/qcom/rpmh.h
new file mode 100644 (file)
index 0000000..c1d0f90
--- /dev/null
+++ b/include/soc/qcom/rpmh.h
@@ -0,0 +1,25 @@
+/* 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>
+
+
+#if IS_ENABLED(CONFIG_QCOM_RPMH)
+int rpmh_write(const struct device *dev, enum rpmh_state state,
+              const struct tcs_cmd *cmd, u32 n);
+
+#else
+
+static inline int rpmh_write(const struct device *dev, enum rpmh_state state,
+                            const struct tcs_cmd *cmd, u32 n)
+{ return -ENODEV; }
+
+#endif /* CONFIG_QCOM_RPMH */
+
+#endif /* __SOC_QCOM_RPMH_H__ */