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| author | Peter Rosin <peda@axentia.se> | 2018-03-29 15:10:54 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-10-03 17:00:50 -0700 |
| commit | 8cbb2f74c0939901d8b96b8fa820afe619790758 (patch) | |
| tree | 2bdcc9d15aec6d932a640364bae1e2107c8b6ca4 | |
| parent | a838008bb11f96f14bfc48a22e88116eb74351ab (diff) | |
| download | linux-stable-8cbb2f74c0939901d8b96b8fa820afe619790758.tar.gz linux-stable-8cbb2f74c0939901d8b96b8fa820afe619790758.tar.bz2 linux-stable-8cbb2f74c0939901d8b96b8fa820afe619790758.zip | |
mtd: rawnand: atmel: add module param to avoid using dma
[ Upstream commit efc6362c6f8c1e74b340e2611f1b35e7d557ce7b ]
On a sama5d31 with a Full-HD dual LVDS panel (132MHz pixel clock) NAND
flash accesses have a tendency to cause display disturbances. Add a
module param to disable DMA from the NAND controller, since that fixes
the display problem for me.
Signed-off-by: Peter Rosin <peda@axentia.se>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/mtd/nand/atmel/nand-controller.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/mtd/nand/atmel/nand-controller.c b/drivers/mtd/nand/atmel/nand-controller.c index 68c9d98a3347..148744418e82 100644 --- a/drivers/mtd/nand/atmel/nand-controller.c +++ b/drivers/mtd/nand/atmel/nand-controller.c @@ -129,6 +129,11 @@ #define DEFAULT_TIMEOUT_MS 1000 #define MIN_DMA_LEN 128 +static bool atmel_nand_avoid_dma __read_mostly; + +MODULE_PARM_DESC(avoiddma, "Avoid using DMA"); +module_param_named(avoiddma, atmel_nand_avoid_dma, bool, 0400); + enum atmel_nand_rb_type { ATMEL_NAND_NO_RB, ATMEL_NAND_NATIVE_RB, @@ -1975,7 +1980,7 @@ static int atmel_nand_controller_init(struct atmel_nand_controller *nc, return ret; } - if (nc->caps->has_dma) { + if (nc->caps->has_dma && !atmel_nand_avoid_dma) { dma_cap_mask_t mask; dma_cap_zero(mask); |