/*
* 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"
static 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);
/*
* Adjust the buffer to point to the beginning of the trace data
* and update the available trace data.
*/
if (val & TMC_STS_FULL) {
drvdata->buf = drvdata->vaddr + rwp - drvdata->paddr;
drvdata->len = drvdata->size;
} else {
drvdata->buf = drvdata->vaddr;
drvdata->len = rwp - drvdata->paddr;
}
}
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 (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)
{
int ret = 0;
bool used = false;
unsigned long flags;
void __iomem *vaddr = NULL;
dma_addr_t paddr;
struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
/*
* 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;
}
/*
* 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 (drvdata->mode == 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;
}
drvdata->mode = CS_MODE_SYSFS;
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)
{
int ret = 0;
unsigned long flags;
struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
spin_lock_irqsave(&drvdata->spinlock, flags);
if (drvdata->reading) {
ret = -EINVAL;
goto out;
}
/*
* 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 (drvdata->mode != CS_MODE_DISABLED) {
ret = -EINVAL;
goto out;
}
drvdata->mode = CS_MODE_PERF;
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);
case CS_MODE_PERF:
return tmc_enable_etr_sink_perf(csdev);
}
/* We shouldn't be here */
return -EINVAL;
}
static void tmc_disable_etr_sink(struct coresight_device *csdev)
{
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;
}
/* Disable the TMC only if it needs to */
if (drvdata->mode != CS_MODE_DISABLED) {
tmc_etr_disable_hw(drvdata);
drvdata->mode = CS_MODE_DISABLED;
}
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;
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;
}
/* Don't interfere if operated from Perf */
if (drvdata->mode == 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 (drvdata->mode == 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 (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;
}