diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-09-11 04:34:46 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-09-11 04:34:46 -0300 |
commit | 863981e96738983919de841ec669e157e6bdaeb0 (patch) | |
tree | d6d89a12e7eb8017837c057935a2271290907f76 /drivers/hwtracing/coresight/coresight-tmc-etr.c | |
parent | 8dec7c70575785729a6a9e6719a955e9c545bcab (diff) |
Linux-libre 4.7.1-gnupck-4.7.1-gnu
Diffstat (limited to 'drivers/hwtracing/coresight/coresight-tmc-etr.c')
-rw-r--r-- | drivers/hwtracing/coresight/coresight-tmc-etr.c | 326 |
1 files changed, 326 insertions, 0 deletions
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c new file mode 100644 index 000000000..688be9e06 --- /dev/null +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c @@ -0,0 +1,326 @@ +/* + * Copyright(C) 2016 Linaro Limited. All rights reserved. + * Author: Mathieu Poirier <mathieu.poirier@linaro.org> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/coresight.h> +#include <linux/dma-mapping.h> +#include "coresight-priv.h" +#include "coresight-tmc.h" + +void tmc_etr_enable_hw(struct tmc_drvdata *drvdata) +{ + u32 axictl; + + /* Zero out the memory to help with debug */ + memset(drvdata->vaddr, 0, drvdata->size); + + CS_UNLOCK(drvdata->base); + + /* Wait for TMCSReady bit to be set */ + tmc_wait_for_tmcready(drvdata); + + writel_relaxed(drvdata->size / 4, drvdata->base + TMC_RSZ); + writel_relaxed(TMC_MODE_CIRCULAR_BUFFER, drvdata->base + TMC_MODE); + + axictl = readl_relaxed(drvdata->base + TMC_AXICTL); + axictl |= TMC_AXICTL_WR_BURST_16; + writel_relaxed(axictl, drvdata->base + TMC_AXICTL); + axictl &= ~TMC_AXICTL_SCT_GAT_MODE; + writel_relaxed(axictl, drvdata->base + TMC_AXICTL); + axictl = (axictl & + ~(TMC_AXICTL_PROT_CTL_B0 | TMC_AXICTL_PROT_CTL_B1)) | + TMC_AXICTL_PROT_CTL_B1; + writel_relaxed(axictl, drvdata->base + TMC_AXICTL); + + writel_relaxed(drvdata->paddr, drvdata->base + TMC_DBALO); + writel_relaxed(0x0, drvdata->base + TMC_DBAHI); + writel_relaxed(TMC_FFCR_EN_FMT | TMC_FFCR_EN_TI | + TMC_FFCR_FON_FLIN | TMC_FFCR_FON_TRIG_EVT | + TMC_FFCR_TRIGON_TRIGIN, + drvdata->base + TMC_FFCR); + writel_relaxed(drvdata->trigger_cntr, drvdata->base + TMC_TRG); + tmc_enable_hw(drvdata); + + CS_LOCK(drvdata->base); +} + +static void tmc_etr_dump_hw(struct tmc_drvdata *drvdata) +{ + u32 rwp, val; + + rwp = readl_relaxed(drvdata->base + TMC_RWP); + val = readl_relaxed(drvdata->base + TMC_STS); + + /* How much memory do we still have */ + if (val & BIT(0)) + drvdata->buf = drvdata->vaddr + rwp - drvdata->paddr; + else + drvdata->buf = drvdata->vaddr; +} + +static void tmc_etr_disable_hw(struct tmc_drvdata *drvdata) +{ + CS_UNLOCK(drvdata->base); + + tmc_flush_and_stop(drvdata); + /* + * When operating in sysFS mode the content of the buffer needs to be + * read before the TMC is disabled. + */ + if (local_read(&drvdata->mode) == CS_MODE_SYSFS) + tmc_etr_dump_hw(drvdata); + tmc_disable_hw(drvdata); + + CS_LOCK(drvdata->base); +} + +static int tmc_enable_etr_sink_sysfs(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; + struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); + + /* This shouldn't be happening */ + if (WARN_ON(mode != CS_MODE_SYSFS)) + return -EINVAL; + + /* + * If we don't have a buffer release the lock and allocate memory. + * Otherwise keep the lock and move along. + */ + spin_lock_irqsave(&drvdata->spinlock, flags); + if (!drvdata->vaddr) { + spin_unlock_irqrestore(&drvdata->spinlock, flags); + + /* + * Contiguous memory can't be allocated while a spinlock is + * held. As such allocate memory here and free it if a buffer + * has already been allocated (from a previous session). + */ + vaddr = dma_alloc_coherent(drvdata->dev, drvdata->size, + &paddr, GFP_KERNEL); + if (!vaddr) + return -ENOMEM; + + /* Let's try again */ + spin_lock_irqsave(&drvdata->spinlock, flags); + } + + if (drvdata->reading) { + ret = -EBUSY; + 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 + * simply use that. + */ + if (drvdata->buf == NULL) { + used = true; + drvdata->vaddr = vaddr; + drvdata->paddr = paddr; + drvdata->buf = drvdata->vaddr; + } + + memset(drvdata->vaddr, 0, drvdata->size); + + tmc_etr_enable_hw(drvdata); +out: + spin_unlock_irqrestore(&drvdata->spinlock, flags); + + /* Free memory outside the spinlock if need be */ + if (!used && vaddr) + dma_free_coherent(drvdata->dev, drvdata->size, vaddr, paddr); + + if (!ret) + dev_info(drvdata->dev, "TMC-ETR enabled\n"); + + return ret; +} + +static int tmc_enable_etr_sink_perf(struct coresight_device *csdev, u32 mode) +{ + int ret = 0; + long val; + unsigned long flags; + struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); + + /* This shouldn't be happening */ + if (WARN_ON(mode != CS_MODE_PERF)) + return -EINVAL; + + spin_lock_irqsave(&drvdata->spinlock, flags); + if (drvdata->reading) { + ret = -EINVAL; + goto out; + } + + val = local_xchg(&drvdata->mode, mode); + /* + * In Perf mode there can be only one writer per sink. There + * is also no need to continue if the ETR is already operated + * from sysFS. + */ + if (val != CS_MODE_DISABLED) { + ret = -EINVAL; + goto out; + } + + tmc_etr_enable_hw(drvdata); +out: + spin_unlock_irqrestore(&drvdata->spinlock, flags); + + return ret; +} + +static int tmc_enable_etr_sink(struct coresight_device *csdev, u32 mode) +{ + switch (mode) { + case CS_MODE_SYSFS: + return tmc_enable_etr_sink_sysfs(csdev, mode); + case CS_MODE_PERF: + return tmc_enable_etr_sink_perf(csdev, mode); + } + + /* We shouldn't be here */ + return -EINVAL; +} + +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); + + spin_lock_irqsave(&drvdata->spinlock, flags); + if (drvdata->reading) { + spin_unlock_irqrestore(&drvdata->spinlock, flags); + return; + } + + 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"); +} + +static const struct coresight_ops_sink tmc_etr_sink_ops = { + .enable = tmc_enable_etr_sink, + .disable = tmc_disable_etr_sink, +}; + +const struct coresight_ops tmc_etr_cs_ops = { + .sink_ops = &tmc_etr_sink_ops, +}; + +int tmc_read_prepare_etr(struct tmc_drvdata *drvdata) +{ + int ret = 0; + long val; + unsigned long flags; + + /* config types are set a boot time and never change */ + if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETR)) + return -EINVAL; + + spin_lock_irqsave(&drvdata->spinlock, flags); + if (drvdata->reading) { + ret = -EBUSY; + goto out; + } + + val = local_read(&drvdata->mode); + /* Don't interfere if operated from Perf */ + if (val == CS_MODE_PERF) { + ret = -EINVAL; + goto out; + } + + /* If drvdata::buf is NULL the trace data has been read already */ + if (drvdata->buf == NULL) { + ret = -EINVAL; + goto out; + } + + /* Disable the TMC if need be */ + if (val == CS_MODE_SYSFS) + tmc_etr_disable_hw(drvdata); + + drvdata->reading = true; +out: + spin_unlock_irqrestore(&drvdata->spinlock, flags); + + return ret; +} + +int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata) +{ + unsigned long flags; + dma_addr_t paddr; + void __iomem *vaddr = NULL; + + /* config types are set a boot time and never change */ + if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETR)) + return -EINVAL; + + spin_lock_irqsave(&drvdata->spinlock, flags); + + /* RE-enable the TMC if need be */ + if (local_read(&drvdata->mode) == CS_MODE_SYSFS) { + /* + * The trace run will continue with the same allocated trace + * buffer. The trace buffer is cleared in tmc_etr_enable_hw(), + * so we don't have to explicitly clear it. Also, since the + * tracer is still enabled drvdata::buf can't be NULL. + */ + tmc_etr_enable_hw(drvdata); + } else { + /* + * The ETR is not tracing and the buffer was just read. + * As such prepare to free the trace buffer. + */ + vaddr = drvdata->vaddr; + paddr = drvdata->paddr; + drvdata->buf = drvdata->vaddr = NULL; + } + + drvdata->reading = false; + spin_unlock_irqrestore(&drvdata->spinlock, flags); + + /* Free allocated memory out side of the spinlock */ + if (vaddr) + dma_free_coherent(drvdata->dev, drvdata->size, vaddr, paddr); + + return 0; +} |