mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-09-06 02:50:43 +00:00
Code Issues Releases Wiki Activity

dmaengine: ti-dma-crossbar: dra7: Use bitops instead of idr

Browse source 
The use of idr was nice, but it was a bit heavy and we did not need the
features it provides. Using simple bitmap to track allocated DMA channels
is adequate here and it will be easier to add support for reserving
channels later on.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This commit is contained in:
Peter Ujfalusi 2015-10-30 10:00:36 +02:00 committed by Vinod Koul
parent 2adb2743b1
commit ec9bfa1e1a
1 changed files with 23 additions and 7 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

30
drivers/dma/ti-dma-crossbar.c
View file

@ -12,7 +12,6 @@
#include <linux/init.h>
#include <linux/list.h>
#include <linux/io.h>
#include <linux/idr.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/of_dma.h>
@ -198,7 +197,8 @@ struct ti_dra7_xbar_data {
void __iomem *iomem;
struct dma_router dmarouter;
struct idr map_idr;
struct mutex mutex;
unsigned long *dma_inuse;
u16 safe_val; /* Value to rest the crossbar lines */
u32 xbar_requests; /* number of DMA requests connected to XBAR */
@ -225,7 +225,9 @@ static void ti_dra7_xbar_free(struct device *dev, void *route_data)
map->xbar_in, map->xbar_out);
ti_dra7_xbar_write(xbar->iomem, map->xbar_out, xbar->safe_val);
idr_remove(&xbar->map_idr, map->xbar_out);
mutex_lock(&xbar->mutex);
clear_bit(map->xbar_out, xbar->dma_inuse);
mutex_unlock(&xbar->mutex);
kfree(map);
}
@ -255,8 +257,17 @@ static void *ti_dra7_xbar_route_allocate(struct of_phandle_args *dma_spec,
return ERR_PTR(-ENOMEM);
}
map->xbar_out = idr_alloc(&xbar->map_idr, NULL, 0, xbar->dma_requests,
GFP_KERNEL);
mutex_lock(&xbar->mutex);
map->xbar_out = find_first_zero_bit(xbar->dma_inuse,
xbar->dma_requests);
mutex_unlock(&xbar->mutex);
if (map->xbar_out == xbar->dma_requests) {
dev_err(&pdev->dev, "Run out of free DMA requests\n");
kfree(map);
return ERR_PTR(-ENOMEM);
}
set_bit(map->xbar_out, xbar->dma_inuse);
map->xbar_in = (u16)dma_spec->args[0];
dma_spec->args[0] = map->xbar_out + xbar->dma_offset;
@ -303,8 +314,6 @@ static int ti_dra7_xbar_probe(struct platform_device *pdev)
if (!xbar)
return -ENOMEM;
idr_init(&xbar->map_idr);
dma_node = of_parse_phandle(node, "dma-masters", 0);
if (!dma_node) {
dev_err(&pdev->dev, "Can't get DMA master node\n");
@ -326,6 +335,12 @@ static int ti_dra7_xbar_probe(struct platform_device *pdev)
}
of_node_put(dma_node);
xbar->dma_inuse = devm_kcalloc(&pdev->dev,
BITS_TO_LONGS(xbar->dma_requests),
sizeof(unsigned long), GFP_KERNEL);
if (!xbar->dma_inuse)
return -ENOMEM;
if (of_property_read_u32(node, "dma-requests", &xbar->xbar_requests)) {
dev_info(&pdev->dev,
"Missing XBAR input information, using %u.\n",
@ -347,6 +362,7 @@ static int ti_dra7_xbar_probe(struct platform_device *pdev)
xbar->dmarouter.route_free = ti_dra7_xbar_free;
xbar->dma_offset = (u32)match->data;
mutex_init(&xbar->mutex);
platform_set_drvdata(pdev, xbar);
/* Reset the crossbar */