Add changes to invoke rpmh flush() from within cache_lock when the data in cache is dirty. Introduce two new APIs for this. Clients can use rpmh_start_transaction() before any rpmh transaction once done invoke rpmh_end_transaction() which internally invokes rpmh_flush() if the caches has become dirty. Add support to control this with flush_dirty flag. Signed-off-by: Maulik Shah <mkshah@xxxxxxxxxxxxxx> Reviewed-by: Srinivas Rao L <lsrao@xxxxxxxxxxxxxx> --- drivers/soc/qcom/rpmh-internal.h | 4 +++ drivers/soc/qcom/rpmh-rsc.c | 6 +++- drivers/soc/qcom/rpmh.c | 64 ++++++++++++++++++++++++++++++++-------- include/soc/qcom/rpmh.h | 10 +++++++ 4 files changed, 71 insertions(+), 13 deletions(-) diff --git a/drivers/soc/qcom/rpmh-internal.h b/drivers/soc/qcom/rpmh-internal.h index 6eec32b..d36be3d 100644 --- a/drivers/soc/qcom/rpmh-internal.h +++ b/drivers/soc/qcom/rpmh-internal.h @@ -70,13 +70,17 @@ struct rpmh_request { * * @cache: the list of cached requests * @cache_lock: synchronize access to the cache data + * @active_clients: count of rpmh transaction in progress * @dirty: was the cache updated since flush + * @flush_dirty: if the dirty cache need immediate flush * @batch_cache: Cache sleep and wake requests sent as batch */ struct rpmh_ctrlr { struct list_head cache; spinlock_t cache_lock; + u32 active_clients; bool dirty; + bool flush_dirty; struct list_head batch_cache; }; diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c index e278fc1..b6391e1 100644 --- a/drivers/soc/qcom/rpmh-rsc.c +++ b/drivers/soc/qcom/rpmh-rsc.c @@ -61,6 +61,8 @@ #define CMD_STATUS_ISSUED BIT(8) #define CMD_STATUS_COMPL BIT(16) +#define FLUSH_DIRTY 1 + static u32 read_tcs_reg(struct rsc_drv *drv, int reg, int tcs_id, int cmd_id) { return readl_relaxed(drv->tcs_base + reg + RSC_DRV_TCS_OFFSET * tcs_id + @@ -670,13 +672,15 @@ static int rpmh_rsc_probe(struct platform_device *pdev) INIT_LIST_HEAD(&drv->client.cache); INIT_LIST_HEAD(&drv->client.batch_cache); + drv->client.flush_dirty = device_get_match_data(&pdev->dev); + dev_set_drvdata(&pdev->dev, drv); return devm_of_platform_populate(&pdev->dev); } static const struct of_device_id rpmh_drv_match[] = { - { .compatible = "qcom,rpmh-rsc", }, + { .compatible = "qcom,rpmh-rsc", .data = (void *)FLUSH_DIRTY }, { } }; diff --git a/drivers/soc/qcom/rpmh.c b/drivers/soc/qcom/rpmh.c index 5bed8f4..9d40209 100644 --- a/drivers/soc/qcom/rpmh.c +++ b/drivers/soc/qcom/rpmh.c @@ -297,12 +297,10 @@ static int flush_batch(struct rpmh_ctrlr *ctrlr) { struct batch_cache_req *req; const struct rpmh_request *rpm_msg; - unsigned long flags; int ret = 0; int i; /* Send Sleep/Wake requests to the controller, expect no response */ - spin_lock_irqsave(&ctrlr->cache_lock, flags); list_for_each_entry(req, &ctrlr->batch_cache, list) { for (i = 0; i < req->count; i++) { rpm_msg = req->rpm_msgs + i; @@ -312,7 +310,6 @@ static int flush_batch(struct rpmh_ctrlr *ctrlr) break; } } - spin_unlock_irqrestore(&ctrlr->cache_lock, flags); return ret; } @@ -433,16 +430,63 @@ static int send_single(struct rpmh_ctrlr *ctrlr, enum rpmh_state state, } /** + * rpmh_start_transaction: Indicates start of rpmh transactions, this + * must be ended by invoking rpmh_end_transaction(). + * + * @dev: the device making the request + */ +void rpmh_start_transaction(const struct device *dev) +{ + struct rpmh_ctrlr *ctrlr = get_rpmh_ctrlr(dev); + unsigned long flags; + + if (!ctrlr->flush_dirty) + return; + + spin_lock_irqsave(&ctrlr->cache_lock, flags); + ctrlr->active_clients++; + spin_unlock_irqrestore(&ctrlr->cache_lock, flags); +} +EXPORT_SYMBOL(rpmh_start_transaction); + +/** + * rpmh_end_transaction: Indicates end of rpmh transactions. All dirty data + * in cache can be flushed immediately when ctrlr->flush_dirty is set + * + * @dev: the device making the request + * + * Return: 0 on success, error number otherwise. + */ +int rpmh_end_transaction(const struct device *dev) +{ + struct rpmh_ctrlr *ctrlr = get_rpmh_ctrlr(dev); + unsigned long flags; + int ret = 0; + + if (!ctrlr->flush_dirty) + return ret; + + spin_lock_irqsave(&ctrlr->cache_lock, flags); + + ctrlr->active_clients--; + if (ctrlr->dirty && !ctrlr->active_clients) + ret = rpmh_flush(ctrlr); + + spin_unlock_irqrestore(&ctrlr->cache_lock, flags); + + return ret; +} +EXPORT_SYMBOL(rpmh_end_transaction); + +/** * rpmh_flush: Flushes the buffered active and sleep sets to TCS * * @ctrlr: controller making request to flush cached data * - * Return: -EBUSY if the controller is busy, probably waiting on a response - * to a RPMH request sent earlier. + * Return: 0 on success, error number otherwise. * - * This function is always called from the sleep code from the last CPU - * that is powering down the entire system. Since no other RPMH API would be - * executing at this time, it is safe to run lockless. + * This function can either be called from sleep code on the last CPU + * (thus no spinlock needed) or with the ctrlr->cache_lock already held. */ int rpmh_flush(struct rpmh_ctrlr *ctrlr) { @@ -464,10 +508,6 @@ int rpmh_flush(struct rpmh_ctrlr *ctrlr) if (ret) return ret; - /* - * Nobody else should be calling this function other than system PM, - * hence we can run without locks. - */ list_for_each_entry(p, &ctrlr->cache, list) { if (!is_req_valid(p)) { pr_debug("%s: skipping RPMH req: a:%#x s:%#x w:%#x", diff --git a/include/soc/qcom/rpmh.h b/include/soc/qcom/rpmh.h index f9ec353..85e1ab2 100644 --- a/include/soc/qcom/rpmh.h +++ b/include/soc/qcom/rpmh.h @@ -22,6 +22,10 @@ int rpmh_write_batch(const struct device *dev, enum rpmh_state state, int rpmh_invalidate(const struct device *dev); +void rpmh_start_transaction(const struct device *dev); + +int rpmh_end_transaction(const struct device *dev); + #else static inline int rpmh_write(const struct device *dev, enum rpmh_state state, @@ -41,6 +45,12 @@ static inline int rpmh_write_batch(const struct device *dev, static inline int rpmh_invalidate(const struct device *dev) { return -ENODEV; } +void rpmh_start_transaction(const struct device *dev) +{ return -ENODEV; } + +int rpmh_end_transaction(const struct device *dev) +{ return -ENODEV; } + #endif /* CONFIG_QCOM_RPMH */ #endif /* __SOC_QCOM_RPMH_H__ */ -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation