[PATCH 3/3] mtd: onenand: implement cache program feature for 4kb page onenand

[Roman Tereshonkov]

Implement cache program feature for 4KB page onenand.
This feature improves the write data performance.
The observed 128KB data program speed change is
from 8827KB/s to 14156 KB/s when the feature is enabled.

Signed-off-by: Roman Tereshonkov <roman.tereshonkov at nokia.com>
---
 drivers/mtd/onenand/omap2.c        |   12 ++++++++--
 drivers/mtd/onenand/onenand_base.c |   39 ++++++++++++++++++++++++++++++++++-
 2 files changed, 46 insertions(+), 5 deletions(-)

diff --git a/drivers/mtd/onenand/omap2.c b/drivers/mtd/onenand/omap2.c
index 9f322f1..da25a90 100644
--- a/drivers/mtd/onenand/omap2.c
+++ b/drivers/mtd/onenand/omap2.c
@@ -108,8 +108,9 @@ static void wait_warn(char *msg, int state, unsigned int ctrl,
 static int omap2_onenand_wait(struct mtd_info *mtd, int state)
 {
 	struct omap2_onenand *c = container_of(mtd, struct omap2_onenand, mtd);
+	struct onenand_chip *this = mtd->priv;
 	unsigned int intr = 0;
-	unsigned int ctrl;
+	unsigned int ctrl, ctrl_mask;
 	unsigned long timeout;
 	u32 syscfg;
 
@@ -180,7 +181,8 @@ retry:
 			if (result == 0) {
 				/* Timeout after 20ms */
 				ctrl = read_reg(c, ONENAND_REG_CTRL_STATUS);
-				if (ctrl & ONENAND_CTRL_ONGO) {
+				if (ctrl & ONENAND_CTRL_ONGO &&
+				    !this->ongoing) {
 					/*
 					 * The operation seems to be still going
 					 * so give it some more time.
@@ -269,7 +271,11 @@ retry:
 		return -EIO;
 	}
 
-	if (ctrl & 0xFE9F)
+	ctrl_mask = 0xFE9F;
+	if (this->ongoing)
+		ctrl_mask &= ~0x8000;
+
+	if (ctrl & ctrl_mask)
 		wait_warn("unexpected controller status", state, ctrl, intr);
 
 	return 0;
diff --git a/drivers/mtd/onenand/onenand_base.c b/drivers/mtd/onenand/onenand_base.c
index 6b3a875..b2c3e97 100644
--- a/drivers/mtd/onenand/onenand_base.c
+++ b/drivers/mtd/onenand/onenand_base.c
@@ -440,6 +440,19 @@ static int onenand_command(struct mtd_info *mtd, int cmd, loff_t addr, size_t le
 		default:
 			if (ONENAND_IS_2PLANE(this) && cmd == ONENAND_CMD_PROG)
 				cmd = ONENAND_CMD_2X_PROG;
+
+			/* Exclude 1st OTP and OTP blocks */
+			if (ONENAND_IS_CACHE_PROGRAM(this) &&
+			    likely(onenand_block(this, addr) != 0) &&
+			    ONENAND_IS_4KB_PAGE(this)) {
+
+				if (cmd == ONENAND_CMD_CACHE_PROG)
+					cmd = ONENAND_CMD_2X_CACHE_PROG;
+				else if (cmd == ONENAND_CMD_CACHE_PROG_LAST)
+					cmd = ONENAND_CMD_PROG;
+
+			}
+
 			dataram = ONENAND_CURRENT_BUFFERRAM(this);
 			break;
 		}
@@ -1845,7 +1858,7 @@ static int onenand_write_ops_nolock(struct mtd_info *mtd, loff_t to,
 	const u_char *buf = ops->datbuf;
 	const u_char *oob = ops->oobbuf;
 	u_char *oobbuf;
-	int ret = 0;
+	int ret = 0, cmd;
 
 	DEBUG(MTD_DEBUG_LEVEL3, "%s: to = 0x%08x, len = %i\n",
 		__func__, (unsigned int) to, (int) len);
@@ -1954,7 +1967,25 @@ static int onenand_write_ops_nolock(struct mtd_info *mtd, loff_t to,
 			ONENAND_SET_NEXT_BUFFERRAM(this);
 		}
 
-		this->command(mtd, ONENAND_CMD_PROG, to, mtd->writesize);
+		this->ongoing = 0;
+
+		/* Exclude 1st OTP and OTP blocks */
+		if (ONENAND_IS_CACHE_PROGRAM(this) &&
+		    likely(onenand_block(this, to) != 0) &&
+		    ONENAND_IS_4KB_PAGE(this)) {
+
+			if ((written + thislen) < len) {
+				cmd = ONENAND_CMD_CACHE_PROG;
+				this->ongoing = 1;
+			} else {
+				cmd = ONENAND_CMD_CACHE_PROG_LAST;
+			}
+
+		} else {
+			cmd = ONENAND_CMD_PROG;
+		}
+
+		this->command(mtd, cmd, to, mtd->writesize);
 
 		/*
 		 * 2 PLANE, MLC, and Flex-OneNAND wait here
@@ -3380,6 +3411,8 @@ static void onenand_check_features(struct mtd_info *mtd)
 		else if (numbufs == 1)
 			this->options |= ONENAND_HAS_4KB_PAGE;
 
+		this->options |= ONENAND_HAS_CACHE_PROGRAM;
+
 	case ONENAND_DEVICE_DENSITY_2Gb:
 		/* 2Gb DDP does not have 2 plane */
 		if (!ONENAND_IS_DDP(this))
@@ -3415,6 +3448,8 @@ static void onenand_check_features(struct mtd_info *mtd)
 		printk(KERN_DEBUG "Chip has 2 plane\n");
 	if (this->options & ONENAND_HAS_4KB_PAGE)
 		printk(KERN_DEBUG "Chip has 4KiB pagesize\n");
+	if (this->options & ONENAND_HAS_CACHE_PROGRAM)
+		printk(KERN_DEBUG "Chip has cache program feature\n");
 }
 
 /**
-- 
1.7.0.4