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coresight-stm: support mmapping channel regions with mmio_addr 

CoreSight STM device allows direct mapping of the channel regions to
userspace for zero-copy writing. To support this ability, the STM
framework has provided a hook 'mmio_addr', this patch just implemented
this hook for CoreSight STM.

This patch also added an item into 'channel_space' to save the physical
base address of channel region which mmap operation needs to know.

Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Chunyan Zhang 2016-08-25 15:18:52 -06:00 committed by Greg Kroah-Hartman
parent b839215372
commit f3864d8562
1 changed files with 22 additions and 0 deletions
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22
drivers/hwtracing/coresight/coresight-stm.c
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@ -105,10 +105,12 @@ module_param_named(
/**
* struct channel_space - central management entity for extended ports
* @base: memory mapped base address where channels start.
* @phys: physical base address of channel region.
* @guaraneed: is the channel delivery guaranteed.
*/
struct channel_space {
void __iomem *base;
phys_addr_t phys;
unsigned long *guaranteed;
};
@ -356,6 +358,23 @@ static void stm_generic_unlink(struct stm_data *stm_data,
stm_disable(drvdata->csdev);
}
static phys_addr_t
stm_mmio_addr(struct stm_data *stm_data, unsigned int master,
unsigned int channel, unsigned int nr_chans)
{
struct stm_drvdata *drvdata = container_of(stm_data,
struct stm_drvdata, stm);
phys_addr_t addr;
addr = drvdata->chs.phys + channel * BYTES_PER_CHANNEL;
if (offset_in_page(addr) ||
offset_in_page(nr_chans * BYTES_PER_CHANNEL))
return 0;
return addr;
}
static long stm_generic_set_options(struct stm_data *stm_data,
unsigned int master,
unsigned int channel,
@ -761,7 +780,9 @@ static void stm_init_generic_data(struct stm_drvdata *drvdata)
drvdata->stm.sw_end = 1;
drvdata->stm.hw_override = true;
drvdata->stm.sw_nchannels = drvdata->numsp;
drvdata->stm.sw_mmiosz = BYTES_PER_CHANNEL;
drvdata->stm.packet = stm_generic_packet;
drvdata->stm.mmio_addr = stm_mmio_addr;
drvdata->stm.link = stm_generic_link;
drvdata->stm.unlink = stm_generic_unlink;
drvdata->stm.set_options = stm_generic_set_options;
@ -808,6 +829,7 @@ static int stm_probe(struct amba_device *adev, const struct amba_id *id)
ret = stm_get_resource_byname(np, "stm-stimulus-base", &ch_res);
if (ret)
return ret;
drvdata->chs.phys = ch_res.start;
base = devm_ioremap_resource(dev, &ch_res);
if (IS_ERR(base))