| Message ID | 1547658629-25378-6-git-send-email-john.stultz@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | k3dma patches to add support for hi3660/HiKey960 | expand |
On Wed, Jan 16, 2019 at 09:10:26AM -0800, John Stultz wrote: > From: Li Yu <liyu65@hisilicon.com> > > Add dma-channel-mask as a property for k3dma, it defines > available dma channels which a non-secure mode driver can use. > > One sample usage of this is in Hi3660 SoC. DMA channel 0 is > reserved to lpm3, which is a coprocessor for power management. So > as a result, any request in kernel (which runs on main processor > and in non-secure mode) should start from at least channel 1. > > Cc: Dan Williams <dan.j.williams@intel.com> > Cc: Vinod Koul <vkoul@kernel.org> > Cc: Tanglei Han <hantanglei@huawei.com> > Cc: Zhuangluan Su <suzhuangluan@hisilicon.com> > Cc: Ryan Grachek <ryan@edited.us> > Cc: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> > Cc: Guodong Xu <guodong.xu@linaro.org> > Cc: dmaengine@vger.kernel.org > Signed-off-by: Li Yu <liyu65@hisilicon.com> > [jstultz: Reworked to use a channel mask] > Signed-off-by: John Stultz <john.stultz@linaro.org> > --- > v3: Rename to hisi-dma-avail-chan > v4: Rename to dma-channel-mask > --- > drivers/dma/k3dma.c | 20 +++++++++++++++++++- > 1 file changed, 19 insertions(+), 1 deletion(-) > > diff --git a/drivers/dma/k3dma.c b/drivers/dma/k3dma.c > index b2060bf..ed19b1f 100644 > --- a/drivers/dma/k3dma.c > +++ b/drivers/dma/k3dma.c > @@ -111,6 +111,7 @@ struct k3_dma_dev { > struct dma_pool *pool; > u32 dma_channels; > u32 dma_requests; > + u32 dma_channel_mask; > unsigned int irq; > }; > > @@ -318,6 +319,9 @@ static void k3_dma_tasklet(unsigned long arg) > /* check new channel request in d->chan_pending */ > spin_lock_irq(&d->lock); > for (pch = 0; pch < d->dma_channels; pch++) { > + if (!(d->dma_channel_mask & (1<<pch))) > + continue; > + As per my comment in bindings patch, the code here gets the assumption that we are skipping the channels which are not masked. Either the property should be named as "dma-avail-chan" or "dma_channel_mask" should have the bit mask of channels which needs to be masked. Then the code will be, /* Skip the channels which are masked */ if ((d->dma_channel_mask) & BIT(pch)) continue; PS: Use BIT() macro where applicable. Thanks, Mani > p = &d->phy[pch]; > > if (p->vchan == NULL && !list_empty(&d->chan_pending)) { > @@ -335,6 +339,9 @@ static void k3_dma_tasklet(unsigned long arg) > spin_unlock_irq(&d->lock); > > for (pch = 0; pch < d->dma_channels; pch++) { > + if (!(d->dma_channel_mask & (1<<pch))) > + continue; > + > if (pch_alloc & (1 << pch)) { > p = &d->phy[pch]; > c = p->vchan; > @@ -855,6 +862,13 @@ static int k3_dma_probe(struct platform_device *op) > "dma-channels", &d->dma_channels); > of_property_read_u32((&op->dev)->of_node, > "dma-requests", &d->dma_requests); > + ret = of_property_read_u32((&op->dev)->of_node, > + "dma-channel-mask", &d->dma_channel_mask); > + if (ret) { > + dev_warn(&op->dev, > + "dma-channel-mask doesn't exist, considering all as available.\n"); > + d->dma_channel_mask = (u32)~0UL; > + } > } > > if (!(soc_data->flags & K3_FLAG_NOCLK)) { > @@ -886,8 +900,12 @@ static int k3_dma_probe(struct platform_device *op) > return -ENOMEM; > > for (i = 0; i < d->dma_channels; i++) { > - struct k3_dma_phy *p = &d->phy[i]; > + struct k3_dma_phy *p; > + > + if (!(d->dma_channel_mask & (1<<i))) > + continue; > > + p = &d->phy[i]; > p->idx = i; > p->base = d->base + i * 0x40; > } > -- > 2.7.4 >
On Thu, Jan 17, 2019 at 9:14 AM Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> wrote: > > /* Skip the channels which are masked */ > if ((d->dma_channel_mask) & BIT(pch)) > continue; Per the discussion w/ Vinod and Rob, I think I'll leave this bit be, so we use the channels in the bitmask. > PS: Use BIT() macro where applicable. But this suggestions I've integrated for v5. Thanks so much for the review! -john
diff --git a/drivers/dma/k3dma.c b/drivers/dma/k3dma.c index b2060bf..ed19b1f 100644 --- a/drivers/dma/k3dma.c +++ b/drivers/dma/k3dma.c @@ -111,6 +111,7 @@ struct k3_dma_dev { struct dma_pool *pool; u32 dma_channels; u32 dma_requests; + u32 dma_channel_mask; unsigned int irq; }; @@ -318,6 +319,9 @@ static void k3_dma_tasklet(unsigned long arg) /* check new channel request in d->chan_pending */ spin_lock_irq(&d->lock); for (pch = 0; pch < d->dma_channels; pch++) { + if (!(d->dma_channel_mask & (1<<pch))) + continue; + p = &d->phy[pch]; if (p->vchan == NULL && !list_empty(&d->chan_pending)) { @@ -335,6 +339,9 @@ static void k3_dma_tasklet(unsigned long arg) spin_unlock_irq(&d->lock); for (pch = 0; pch < d->dma_channels; pch++) { + if (!(d->dma_channel_mask & (1<<pch))) + continue; + if (pch_alloc & (1 << pch)) { p = &d->phy[pch]; c = p->vchan; @@ -855,6 +862,13 @@ static int k3_dma_probe(struct platform_device *op) "dma-channels", &d->dma_channels); of_property_read_u32((&op->dev)->of_node, "dma-requests", &d->dma_requests); + ret = of_property_read_u32((&op->dev)->of_node, + "dma-channel-mask", &d->dma_channel_mask); + if (ret) { + dev_warn(&op->dev, + "dma-channel-mask doesn't exist, considering all as available.\n"); + d->dma_channel_mask = (u32)~0UL; + } } if (!(soc_data->flags & K3_FLAG_NOCLK)) { @@ -886,8 +900,12 @@ static int k3_dma_probe(struct platform_device *op) return -ENOMEM; for (i = 0; i < d->dma_channels; i++) { - struct k3_dma_phy *p = &d->phy[i]; + struct k3_dma_phy *p; + + if (!(d->dma_channel_mask & (1<<i))) + continue; + p = &d->phy[i]; p->idx = i; p->base = d->base + i * 0x40; }