From f2facc3366d77e78dbc8bf865f1e4a6227a7f0e5 Mon Sep 17 00:00:00 2001 From: Mathieu Poirier Date: Tue, 3 May 2016 11:33:54 -0600 Subject: coresight: tmc: adding mode of operation for link/sinks Moving tmc_drvdata::enable to a local_t mode. That way the sink interface is aware of it's orgin and the foundation for mutual exclusion between the sysFS and Perf interface can be laid out. Signed-off-by: Mathieu Poirier Reviewed-by: Suzuki K Poulose Signed-off-by: Greg Kroah-Hartman --- drivers/hwtracing/coresight/coresight-tmc-etf.c | 27 ++++++++++++++++++------- drivers/hwtracing/coresight/coresight-tmc-etr.c | 23 ++++++++++++++++----- drivers/hwtracing/coresight/coresight-tmc.h | 4 ++-- 3 files changed, 40 insertions(+), 14 deletions(-) (limited to 'drivers/hwtracing') diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c index 60edf4d1968f..bc0efc1e5b49 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etf.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c @@ -111,6 +111,7 @@ static int tmc_enable_etf_sink(struct coresight_device *csdev, u32 mode) int ret = 0; bool used = false; char *buf = NULL; + long val; unsigned long flags; struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); @@ -140,6 +141,15 @@ static int tmc_enable_etf_sink(struct coresight_device *csdev, u32 mode) goto out; } + val = local_xchg(&drvdata->mode, mode); + /* + * In sysFS mode we can have multiple writers per sink. Since this + * sink is already enabled no memory is needed and the HW need not be + * touched. + */ + if (val == CS_MODE_SYSFS) + goto out; + /* * If drvdata::buf isn't NULL, memory was allocated for a previous * trace run but wasn't read. If so simply zero-out the memory. @@ -157,7 +167,6 @@ static int tmc_enable_etf_sink(struct coresight_device *csdev, u32 mode) } tmc_etb_enable_hw(drvdata); - drvdata->enable = true; out: spin_unlock_irqrestore(&drvdata->spinlock, flags); @@ -173,6 +182,7 @@ out: static void tmc_disable_etf_sink(struct coresight_device *csdev) { + long val; unsigned long flags; struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); @@ -182,8 +192,11 @@ static void tmc_disable_etf_sink(struct coresight_device *csdev) return; } - tmc_etb_disable_hw(drvdata); - drvdata->enable = false; + val = local_xchg(&drvdata->mode, CS_MODE_DISABLED); + /* Disable the TMC only if it needs to */ + if (val != CS_MODE_DISABLED) + tmc_etb_disable_hw(drvdata); + spin_unlock_irqrestore(&drvdata->spinlock, flags); dev_info(drvdata->dev, "TMC-ETB/ETF disabled\n"); @@ -202,7 +215,7 @@ static int tmc_enable_etf_link(struct coresight_device *csdev, } tmc_etf_enable_hw(drvdata); - drvdata->enable = true; + local_set(&drvdata->mode, CS_MODE_SYSFS); spin_unlock_irqrestore(&drvdata->spinlock, flags); dev_info(drvdata->dev, "TMC-ETF enabled\n"); @@ -222,7 +235,7 @@ static void tmc_disable_etf_link(struct coresight_device *csdev, } tmc_etf_disable_hw(drvdata); - drvdata->enable = false; + local_set(&drvdata->mode, CS_MODE_DISABLED); spin_unlock_irqrestore(&drvdata->spinlock, flags); dev_info(drvdata->dev, "TMC disabled\n"); @@ -279,7 +292,7 @@ int tmc_read_prepare_etb(struct tmc_drvdata *drvdata) } /* Disable the TMC if need be */ - if (drvdata->enable) + if (local_read(&drvdata->mode) == CS_MODE_SYSFS) tmc_etb_disable_hw(drvdata); drvdata->reading = true; @@ -310,7 +323,7 @@ int tmc_read_unprepare_etb(struct tmc_drvdata *drvdata) } /* Re-enable the TMC if need be */ - if (drvdata->enable) { + if (local_read(&drvdata->mode) == CS_MODE_SYSFS) { /* * The trace run will continue with the same allocated trace * buffer. As such zero-out the buffer so that we don't end diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c index d6999b457fb8..0c107811a232 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c @@ -86,6 +86,7 @@ static int tmc_enable_etr_sink(struct coresight_device *csdev, u32 mode) { int ret = 0; bool used = false; + long val; unsigned long flags; void __iomem *vaddr = NULL; dma_addr_t paddr; @@ -122,6 +123,15 @@ static int tmc_enable_etr_sink(struct coresight_device *csdev, u32 mode) goto out; } + val = local_xchg(&drvdata->mode, mode); + /* + * In sysFS mode we can have multiple writers per sink. Since this + * sink is already enabled no memory is needed and the HW need not be + * touched. + */ + if (val == CS_MODE_SYSFS) + goto out; + /* * If drvdata::buf == NULL, use the memory allocated above. * Otherwise a buffer still exists from a previous session, so @@ -137,7 +147,6 @@ static int tmc_enable_etr_sink(struct coresight_device *csdev, u32 mode) memset(drvdata->vaddr, 0, drvdata->size); tmc_etr_enable_hw(drvdata); - drvdata->enable = true; out: spin_unlock_irqrestore(&drvdata->spinlock, flags); @@ -153,6 +162,7 @@ out: static void tmc_disable_etr_sink(struct coresight_device *csdev) { + long val; unsigned long flags; struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); @@ -162,8 +172,11 @@ static void tmc_disable_etr_sink(struct coresight_device *csdev) return; } - tmc_etr_disable_hw(drvdata); - drvdata->enable = false; + val = local_xchg(&drvdata->mode, CS_MODE_DISABLED); + /* Disable the TMC only if it needs to */ + if (val != CS_MODE_DISABLED) + tmc_etr_disable_hw(drvdata); + spin_unlock_irqrestore(&drvdata->spinlock, flags); dev_info(drvdata->dev, "TMC-ETR disabled\n"); @@ -200,7 +213,7 @@ int tmc_read_prepare_etr(struct tmc_drvdata *drvdata) } /* Disable the TMC if need be */ - if (drvdata->enable) + if (local_read(&drvdata->mode) == CS_MODE_SYSFS) tmc_etr_disable_hw(drvdata); drvdata->reading = true; @@ -223,7 +236,7 @@ int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata) spin_lock_irqsave(&drvdata->spinlock, flags); /* RE-enable the TMC if need be */ - if (drvdata->enable) { + if (local_read(&drvdata->mode) == CS_MODE_SYSFS) { /* * The trace run will continue with the same allocated trace * buffer. As such zero-out the buffer so that we don't end diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h index 592eb149fe3a..94bc034d3b98 100644 --- a/drivers/hwtracing/coresight/coresight-tmc.h +++ b/drivers/hwtracing/coresight/coresight-tmc.h @@ -98,7 +98,7 @@ enum tmc_mem_intf_width { * @paddr: DMA start location in RAM. * @vaddr: virtual representation of @paddr. * @size: @buf size. - * @enable: this TMC is being used. + * @mode: how this TMC is being used. * @config_type: TMC variant, must be of type @tmc_config_type. * @trigger_cntr: amount of words to store after a trigger. */ @@ -113,7 +113,7 @@ struct tmc_drvdata { dma_addr_t paddr; void __iomem *vaddr; u32 size; - bool enable; + local_t mode; enum tmc_config_type config_type; u32 trigger_cntr; }; -- cgit v1.2.3