| Message ID | 1327392649-27605-1-git-send-email-ldewangan@nvidia.com |
|---|---|
| State | Accepted, archived |
| Headers | show |
Laxman Dewangan wrote at Tuesday, January 24, 2012 1:11 AM: > It is not require to move the requestor of dma to INVALID > option before stopping dma. > > Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com> Acked-by: Stephen Warren <swarren@nvidia.com> Tested-by: Stephen Warren <swarren@nvidia.com> I know that Laxman has checked with the HW engineers, and they see no reason to do this. I was originally worried about hung FIFOs preventing an in-progress DMA from completely without the removed code, but according to HW, that isn't a concern.
On Wednesday 25 January 2012 02:27 AM, Stephen Warren wrote: > Laxman Dewangan wrote at Tuesday, January 24, 2012 1:11 AM: >> It is not require to move the requestor of dma to INVALID >> option before stopping dma. >> >> Signed-off-by: Laxman Dewangan<ldewangan@nvidia.com> > Acked-by: Stephen Warren<swarren@nvidia.com> > Tested-by: Stephen Warren<swarren@nvidia.com> > > I know that Laxman has checked with the HW engineers, and they see no > reason to do this. I was originally worried about hung FIFOs preventing > an in-progress DMA from completely without the removed code, but according > to HW, that isn't a concern. > Olaf, Can it be applied if it is OK to you? Thanks, Laxman -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, Jan 31, 2012 at 04:32:48PM +0530, Laxman Dewangan wrote: > On Wednesday 25 January 2012 02:27 AM, Stephen Warren wrote: > >Laxman Dewangan wrote at Tuesday, January 24, 2012 1:11 AM: > >>It is not require to move the requestor of dma to INVALID > >>option before stopping dma. > >> > >>Signed-off-by: Laxman Dewangan<ldewangan@nvidia.com> > >Acked-by: Stephen Warren<swarren@nvidia.com> > >Tested-by: Stephen Warren<swarren@nvidia.com> > > > >I know that Laxman has checked with the HW engineers, and they see no > >reason to do this. I was originally worried about hung FIFOs preventing > >an in-progress DMA from completely without the removed code, but according > >to HW, that isn't a concern. > > > Olaf, > Can it be applied if it is OK to you? Yep, applied. -Olof -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/arm/mach-tegra/dma.c b/arch/arm/mach-tegra/dma.c index 998c55d..abea4f6 100644 --- a/arch/arm/mach-tegra/dma.c +++ b/arch/arm/mach-tegra/dma.c @@ -52,8 +52,6 @@ #define CSR_ONCE (1<<27) #define CSR_FLOW (1<<21) #define CSR_REQ_SEL_SHIFT 16 -#define CSR_REQ_SEL_MASK (0x1F<<CSR_REQ_SEL_SHIFT) -#define CSR_REQ_SEL_INVALID (31<<CSR_REQ_SEL_SHIFT) #define CSR_WCOUNT_SHIFT 2 #define CSR_WCOUNT_MASK 0xFFFC @@ -183,18 +181,12 @@ static void tegra_dma_stop(struct tegra_dma_channel *ch) static int tegra_dma_cancel(struct tegra_dma_channel *ch) { - u32 csr; unsigned long irq_flags; spin_lock_irqsave(&ch->lock, irq_flags); while (!list_empty(&ch->list)) list_del(ch->list.next); - csr = readl(ch->addr + APB_DMA_CHAN_CSR); - csr &= ~CSR_REQ_SEL_MASK; - csr |= CSR_REQ_SEL_INVALID; - writel(csr, ch->addr + APB_DMA_CHAN_CSR); - tegra_dma_stop(ch); spin_unlock_irqrestore(&ch->lock, irq_flags);
It is not require to move the requestor of dma to INVALID option before stopping dma. Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com> --- arch/arm/mach-tegra/dma.c | 8 -------- 1 files changed, 0 insertions(+), 8 deletions(-)