openwrt/target/linux/brcm2708/patches-4.4/0393-dmaengine-bcm2835-remove-unnecessary-masking-of-dma-.patch
Álvaro Fernández Rojas 2b1c6b21b5 brcm2708: update linux 4.4 patches to latest version
As usual these patches were extracted and rebased from the raspberry pi repo:
https://github.com/raspberrypi/linux/tree/rpi-4.4.y

Also adds support for Raspberry Pi Compute Module 3 (untested).

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
2016-09-10 14:54:26 +02:00

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1.9 KiB
Diff

From 0f65c306a55ab6a8e8148b6d9c966a1d214ae3c9 Mon Sep 17 00:00:00 2001
From: Martin Sperl <kernel@martin.sperl.org>
Date: Wed, 16 Mar 2016 12:24:56 -0700
Subject: [PATCH] dmaengine: bcm2835: remove unnecessary masking of dma
channels
The original patch contained 3 dma channels that were masked out.
These - as far as research and discussions show - are a
artefacts remaining from the downstream legacy dma-api.
Right now down-stream still includes a legacy api used only
in a single (downstream only) driver (bcm2708_fb) that requires
2D DMA for speedup (DMA-channel 0).
Formerly the sd-card support driver also was using this legacy
api (DMA-channel 2), but since has been moved over to use
dmaengine directly.
The DMA-channel 3 is already masked out in the devicetree in
the default property "brcm,dma-channel-mask = <0x7f35>;"
So we can remove the whole masking of DMA channels.
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
---
drivers/dma/bcm2835-dma.c | 9 ---------
1 file changed, 9 deletions(-)
--- a/drivers/dma/bcm2835-dma.c
+++ b/drivers/dma/bcm2835-dma.c
@@ -123,9 +123,6 @@ struct bcm2835_desc {
#define BCM2835_DMA_DATA_TYPE_S32 4
#define BCM2835_DMA_DATA_TYPE_S128 16
-#define BCM2835_DMA_BULK_MASK BIT(0)
-#define BCM2835_DMA_FIQ_MASK (BIT(2) | BIT(3))
-
/* Valid only for channels 0 - 14, 15 has its own base address */
#define BCM2835_DMA_CHAN(n) ((n) << 8) /* Base address */
#define BCM2835_DMA_CHANIO(base, n) ((base) + BCM2835_DMA_CHAN(n))
@@ -641,12 +638,6 @@ static int bcm2835_dma_probe(struct plat
goto err_no_dma;
}
- /*
- * Do not use the FIQ and BULK channels,
- * because they are used by the GPU.
- */
- chans_available &= ~(BCM2835_DMA_FIQ_MASK | BCM2835_DMA_BULK_MASK);
-
for (i = 0; i < pdev->num_resources; i++) {
irq = platform_get_irq(pdev, i);
if (irq < 0)