[PATCH 4.5 032/200] dmaengine: pxa_dma: fix the maximum requestor line

Greg Kroah-Hartman
2016-05-03T01:22:07Z

From: Robert Jarzmik <robert.jarzmik@free.fr>

commit 6bab1c6afdca0371cfa957079b36b78d12dd2cf5 upstream.

The current number of requestor lines is limited to 31. This was an
error of a previous commit, as this number is platform dependent, and is
actually :
- for pxa25x: 40 requestor lines
- for pxa27x: 75 requestor lines
- for pxa3xx: 100 requestor lines

The previous testing did not reveal the faulty constant as on pxa[23]xx
platforms, only camera, MSL and USB are above requestor 32, and in these
only the camera has a driver using dma.

Fixes: e87ffbdf0697 ("dmaengine: pxa_dma: fix the no-requestor case")
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/dma/pxa_dma.c | 39 ++++++++++++++++++++++++++++-----------
1 file changed, 28 insertions(+), 11 deletions(-)

--- a/drivers/dma/pxa_dma.c
+++ b/drivers/dma/pxa_dma.c
@@ -122,6 +122,7 @@ struct pxad_chan {
struct pxad_device {
struct dma_device slave;
int nr_chans;
+ int nr_requestors;
void __iomem *base;
struct pxad_phy *phys;
spinlock_t phy_lock; /* Phy association */
@@ -473,7 +474,7 @@ static void pxad_free_phy(struct pxad_ch
return;

/* clear the channel mapping in DRCMR */
- if (chan->drcmr <= DRCMR_CHLNUM) {
+ if (chan->drcmr <= pdev->nr_requestors) {
reg = pxad_drcmr(chan->drcmr);
writel_relaxed(0, chan->phy->base + reg);
}
@@ -509,6 +510,7 @@ static bool is_running_chan_misaligned(s

static void phy_enable(struct pxad_phy *phy, bool misaligned)
{
+ struct pxad_device *pdev;
u32 reg, dalgn;

if (!phy->vchan)
@@ -518,7 +520,8 @@ static void phy_enable(struct pxad_phy *
"%s(); phy=%p(%d) misaligned=%d\n", __func__,
phy, phy->idx, misaligned);

- if (phy->vchan->drcmr <= DRCMR_CHLNUM) {
+ pdev = to_pxad_dev(phy->vchan->vc.chan.device);
+ if (phy->vchan->drcmr <= pdev->nr_requestors) {
reg = pxad_drcmr(phy->vchan->drcmr);
writel_relaxed(DRCMR_MAPVLD | phy->idx, phy->base + reg);
}
@@ -914,6 +917,7 @@ static void pxad_get_config(struct pxad_
{
u32 maxburst = 0, dev_addr = 0;
enum dma_slave_buswidth width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
+ struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);

*dcmd = 0;
if (dir == DMA_DEV_TO_MEM) {
@@ -922,7 +926,7 @@ static void pxad_get_config(struct pxad_
dev_addr = chan->cfg.src_addr;
*dev_src = dev_addr;
*dcmd |= PXA_DCMD_INCTRGADDR;
- if (chan->drcmr <= DRCMR_CHLNUM)
+ if (chan->drcmr <= pdev->nr_requestors)
*dcmd |= PXA_DCMD_FLOWSRC;
}
if (dir == DMA_MEM_TO_DEV) {
@@ -931,7 +935,7 @@ static void pxad_get_config(struct pxad_
dev_addr = chan->cfg.dst_addr;
*dev_dst = dev_addr;
*dcmd |= PXA_DCMD_INCSRCADDR;
- if (chan->drcmr <= DRCMR_CHLNUM)
+ if (chan->drcmr <= pdev->nr_requestors)
*dcmd |= PXA_DCMD_FLOWTRG;
}
if (dir == DMA_MEM_TO_MEM)
@@ -1341,13 +1345,15 @@ static struct dma_chan *pxad_dma_xlate(s

static int pxad_init_dmadev(struct platform_device *op,
struct pxad_device *pdev,
- unsigned int nr_phy_chans)
+ unsigned int nr_phy_chans,
+ unsigned int nr_requestors)
{
int ret;
unsigned int i;
struct pxad_chan *c;

pdev->nr_chans = nr_phy_chans;
+ pdev->nr_requestors = nr_requestors;
INIT_LIST_HEAD(&pdev->slave.channels);
pdev->slave.device_alloc_chan_resources = pxad_alloc_chan_resources;
pdev->slave.device_free_chan_resources = pxad_free_chan_resources;
@@ -1382,7 +1388,7 @@ static int pxad_probe(struct platform_de
const struct of_device_id *of_id;
struct mmp_dma_platdata *pdata = dev_get_platdata(&op->dev);
struct resource *iores;
- int ret, dma_channels = 0;
+ int ret, dma_channels = 0, nb_requestors = 0;
const enum dma_slave_buswidth widths =
DMA_SLAVE_BUSWIDTH_1_BYTE | DMA_SLAVE_BUSWIDTH_2_BYTES |
DMA_SLAVE_BUSWIDTH_4_BYTES;
@@ -1399,13 +1405,23 @@ static int pxad_probe(struct platform_de
return PTR_ERR(pdev->base);

of_id = of_match_device(pxad_dt_ids, &op->dev);
- if (of_id)
+ if (of_id) {
of_property_read_u32(op->dev.of_node, "#dma-channels",
&dma_channels);
- else if (pdata && pdata->dma_channels)
+ ret = of_property_read_u32(op->dev.of_node, "#dma-requests",
+ &nb_requestors);
+ if (ret) {
+ dev_warn(pdev->slave.dev,
+ "#dma-requests set to default 32 as missing in OF: %d",
+ ret);
+ nb_requestors = 32;
+ };
+ } else if (pdata && pdata->dma_channels) {
dma_channels = pdata->dma_channels;
- else
+ nb_requestors = pdata->nb_requestors;
+ } else {
dma_channels = 32; /* default 32 channel */
+ }

dma_cap_set(DMA_SLAVE, pdev->slave.cap_mask);
dma_cap_set(DMA_MEMCPY, pdev->slave.cap_mask);
@@ -1423,7 +1439,7 @@ static int pxad_probe(struct platform_de
pdev->slave.descriptor_reuse = true;

pdev->slave.dev = &op->dev;
- ret = pxad_init_dmadev(op, pdev, dma_channels);
+ ret = pxad_init_dmadev(op, pdev, dma_channels, nb_requestors);
if (ret) {
dev_err(pdev->slave.dev, "unable to register\n");
return ret;
@@ -1442,7 +1458,8 @@ static int pxad_probe(struct platform_de

platform_set_drvdata(op, pdev);
pxad_init_debugfs(pdev);
- dev_info(pdev->slave.dev, "initialized %d channels\n", dma_channels);
+ dev_info(pdev->slave.dev, "initialized %d channels on %d requestors\n",
+ dma_channels, nb_requestors);
return 0;
}