mtd: sh_flctl: Add DMA capabilty

The code probes if DMA channels can get allocated and tears them down at
removal/failure if needed.
If available it uses them to transfer the data part (not ECC). On
failure we fall back to PIO mode.

Based on Guennadi Liakhovetski's code from the sh_mmcif driver.

Signed-off-by: Bastian Hecht <hechtb@gmail.com>
Reviewed-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/include/linux/mtd/sh_flctl.h b/include/linux/mtd/sh_flctl.h
index 481557688d05..1c28f8879b1c 100644
--- a/include/linux/mtd/sh_flctl.h
+++ b/include/linux/mtd/sh_flctl.h
@@ -20,6 +20,7 @@
 #ifndef __SH_FLCTL_H__
 #define __SH_FLCTL_H__
 
+#include <linux/completion.h>
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/nand.h>
 #include <linux/mtd/partitions.h>
@@ -107,6 +108,7 @@
 #define ESTERINTE       (0x1 << 24)     /* ECC error interrupt enable */
 #define AC1CLR          (0x1 << 19)     /* ECC FIFO clear */
 #define AC0CLR          (0x1 << 18)     /* Data FIFO clear */
+#define DREQ0EN         (0x1 << 16)     /* FLDTFIFODMA Request Enable */
 #define ECERB           (0x1 << 9)      /* ECC error */
 #define STERB           (0x1 << 8)      /* Status error */
 #define STERINTE        (0x1 << 4)      /* Status error enable */
@@ -138,6 +140,8 @@ enum flctl_ecc_res_t {
         FL_TIMEOUT
 };
 
+struct dma_chan;
+
 struct sh_flctl {
         struct mtd_info         mtd;
         struct nand_chip        chip;
@@ -161,6 +165,11 @@ struct sh_flctl {
         unsigned hwecc:1;       /* Hardware ECC (0 = disabled, 1 = enabled) */
         unsigned holden:1;      /* Hardware has FLHOLDCR and HOLDEN is set */
         unsigned qos_request:1; /* QoS request to prevent deep power shutdown */
+
+        /* DMA related objects */
+        struct dma_chan         *chan_fifo0_rx;
+        struct dma_chan         *chan_fifo0_tx;
+        struct completion       dma_complete;
 };
 
 struct sh_flctl_platform_data {
@@ -170,6 +179,9 @@ struct sh_flctl_platform_data {
 
         unsigned has_hwecc:1;
         unsigned use_holden:1;
+
+        unsigned int            slave_id_fifo0_tx;
+        unsigned int            slave_id_fifo0_rx;
 };
 
 static inline struct sh_flctl *mtd_to_flctl(struct mtd_info *mtdinfo)