diff options
author | Peter Rosin <peda@axentia.se> | 2018-03-29 16:10:54 +0300 |
---|---|---|
committer | Miquel Raynal <miquel.raynal@bootlin.com> | 2018-07-02 10:01:29 +0300 |
commit | efc6362c6f8c1e74b340e2611f1b35e7d557ce7b (patch) | |
tree | ea08b48a75c20ce4c2e61092bc0aa445c318f5f4 /drivers/mtd/nand/raw/atmel | |
parent | 021c91791a5e7e85c567452f1be3e4c2c6cb6063 (diff) | |
download | linux-efc6362c6f8c1e74b340e2611f1b35e7d557ce7b.tar.xz |
mtd: rawnand: atmel: add module param to avoid using dma
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>
Diffstat (limited to 'drivers/mtd/nand/raw/atmel')
-rw-r--r-- | drivers/mtd/nand/raw/atmel/nand-controller.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/mtd/nand/raw/atmel/nand-controller.c b/drivers/mtd/nand/raw/atmel/nand-controller.c index 12f6753d47ae..e686fe73159e 100644 --- a/drivers/mtd/nand/raw/atmel/nand-controller.c +++ b/drivers/mtd/nand/raw/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, @@ -1977,7 +1982,7 @@ 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); |