diff options
author | Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org> | 2020-07-16 11:57:34 -0600 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-07-21 15:48:38 +0200 |
commit | 8f3ce74c20f21e09644d2a584238f1453a00eb8d (patch) | |
tree | 57cd25d60b3b57ada23f9fc6dbfc54f006f0b03a /drivers/hwtracing | |
parent | 7f1a1c2c57dbda7278ef06700efcac63433b9893 (diff) |
coresight: replicator: Reset replicator if context is lost
On some QCOM SoCs, replicators in Always-On domain loses its
context as soon as the clock is disabled. Currently as a part
of pm_runtime workqueue, clock is disabled after the replicator
is initialized by amba_pm_runtime_suspend assuming that context
is not lost which is not true for replicators with such
limitations. So add a new property "qcom,replicator-loses-context"
to identify such replicators and reset them.
Suggested-by: Mike Leach <mike.leach@linaro.org>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20200716175746.3338735-6-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/hwtracing')
-rw-r--r-- | drivers/hwtracing/coresight/coresight-replicator.c | 55 |
1 files changed, 38 insertions, 17 deletions
diff --git a/drivers/hwtracing/coresight/coresight-replicator.c b/drivers/hwtracing/coresight/coresight-replicator.c index c619b456f55a..78acf29c49ca 100644 --- a/drivers/hwtracing/coresight/coresight-replicator.c +++ b/drivers/hwtracing/coresight/coresight-replicator.c @@ -14,6 +14,7 @@ #include <linux/err.h> #include <linux/slab.h> #include <linux/pm_runtime.h> +#include <linux/property.h> #include <linux/clk.h> #include <linux/of.h> #include <linux/coresight.h> @@ -32,12 +33,14 @@ DEFINE_CORESIGHT_DEVLIST(replicator_devs, "replicator"); * @atclk: optional clock for the core parts of the replicator. * @csdev: component vitals needed by the framework * @spinlock: serialize enable/disable operations. + * @check_idfilter_val: check if the context is lost upon clock removal. */ struct replicator_drvdata { void __iomem *base; struct clk *atclk; struct coresight_device *csdev; spinlock_t spinlock; + bool check_idfilter_val; }; static void dynamic_replicator_reset(struct replicator_drvdata *drvdata) @@ -66,29 +69,43 @@ static int dynamic_replicator_enable(struct replicator_drvdata *drvdata, int inport, int outport) { int rc = 0; - u32 reg; - - switch (outport) { - case 0: - reg = REPLICATOR_IDFILTER0; - break; - case 1: - reg = REPLICATOR_IDFILTER1; - break; - default: - WARN_ON(1); - return -EINVAL; - } + u32 id0val, id1val; CS_UNLOCK(drvdata->base); - if ((readl_relaxed(drvdata->base + REPLICATOR_IDFILTER0) == 0xff) && - (readl_relaxed(drvdata->base + REPLICATOR_IDFILTER1) == 0xff)) + id0val = readl_relaxed(drvdata->base + REPLICATOR_IDFILTER0); + id1val = readl_relaxed(drvdata->base + REPLICATOR_IDFILTER1); + + /* + * Some replicator designs lose context when AMBA clocks are removed, + * so have a check for this. + */ + if (drvdata->check_idfilter_val && id0val == 0x0 && id1val == 0x0) + id0val = id1val = 0xff; + + if (id0val == 0xff && id1val == 0xff) rc = coresight_claim_device_unlocked(drvdata->base); + if (!rc) { + switch (outport) { + case 0: + id0val = 0x0; + break; + case 1: + id1val = 0x0; + break; + default: + WARN_ON(1); + rc = -EINVAL; + } + } + /* Ensure that the outport is enabled. */ - if (!rc) - writel_relaxed(0x00, drvdata->base + reg); + if (!rc) { + writel_relaxed(id0val, drvdata->base + REPLICATOR_IDFILTER0); + writel_relaxed(id1val, drvdata->base + REPLICATOR_IDFILTER1); + } + CS_LOCK(drvdata->base); return rc; @@ -239,6 +256,10 @@ static int replicator_probe(struct device *dev, struct resource *res) desc.groups = replicator_groups; } + if (fwnode_property_present(dev_fwnode(dev), + "qcom,replicator-loses-context")) + drvdata->check_idfilter_val = true; + dev_set_drvdata(dev, drvdata); pdata = coresight_get_platform_data(dev); |