mtd: gpmi: decouple the chip select from the DMA channel

Decouple the chip select from the DMA channel, we use the DMA channel 0
to accecc all the nand devices.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

2 files changed, 9 insertions, 0 deletions

diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c
index 4f8857fa48a7..7d56d87599c0 100644
--- a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c
+++ b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c
@@ -187,6 +187,12 @@ int gpmi_init(struct gpmi_nand_data *this)
         /* Select BCH ECC. */
         writel(BM_GPMI_CTRL1_BCH_MODE, r->gpmi_regs + HW_GPMI_CTRL1_SET);
 
+        /*
+         * Decouple the chip select from dma channel. We use dma0 for all
+         * the chips.
+         */
+        writel(BM_GPMI_CTRL1_DECOUPLE_CS, r->gpmi_regs + HW_GPMI_CTRL1_SET);
+
         gpmi_disable_clk(this);
         return 0;
 err_out:
diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-regs.h b/drivers/mtd/nand/gpmi-nand/gpmi-regs.h
index 53397cc290fc..82114cdc8330 100644
--- a/drivers/mtd/nand/gpmi-nand/gpmi-regs.h
+++ b/drivers/mtd/nand/gpmi-nand/gpmi-regs.h
@@ -108,6 +108,9 @@
 #define HW_GPMI_CTRL1_CLR                               0x00000068
 #define HW_GPMI_CTRL1_TOG                               0x0000006c
 
+#define BP_GPMI_CTRL1_DECOUPLE_CS                       24
+#define BM_GPMI_CTRL1_DECOUPLE_CS       (1 << BP_GPMI_CTRL1_DECOUPLE_CS)
+
 #define BP_GPMI_CTRL1_WRN_DLY_SEL                       22
 #define BM_GPMI_CTRL1_WRN_DLY_SEL       (0x3 << BP_GPMI_CTRL1_WRN_DLY_SEL)
 #define BF_GPMI_CTRL1_WRN_DLY_SEL(v)  \