X-Git-Url: https://git.sur5r.net/?a=blobdiff_plain;ds=sidebyside;f=drivers%2Fmtd%2Fnand%2Fomap_gpmc.c;h=fc64f4814484e8052410f4769c60240ae67dc510;hb=c316f57;hp=40d670563c1e447c172f075eabda3d304433f693;hpb=625509ab0edbb7d943ad9028de3c21ca48aa58be;p=u-boot

diff --git a/drivers/mtd/nand/omap_gpmc.c b/drivers/mtd/nand/omap_gpmc.c
index 40d670563c..fc64f48144 100644
--- a/drivers/mtd/nand/omap_gpmc.c
+++ b/drivers/mtd/nand/omap_gpmc.c
@@ -73,14 +73,11 @@ static void omap_nand_hwcontrol(struct mtd_info *mtd, int32_t cmd,
 		writeb(cmd, this->IO_ADDR_W);
 }
 
-#ifdef CONFIG_SPL_BUILD
 /* Check wait pin as dev ready indicator */
-static int omap_spl_dev_ready(struct mtd_info *mtd)
+static int omap_dev_ready(struct mtd_info *mtd)
 {
 	return gpmc_cfg->status & (1 << 8);
 }
-#endif
-
 
 /*
  * gen_true_ecc - This function will generate true ECC value, which
@@ -371,8 +368,9 @@ static int omap_correct_data_bch(struct mtd_info *mtd, uint8_t *dat,
 	uint32_t error_loc[ELM_MAX_ERROR_COUNT];
 	enum bch_level bch_type;
 	uint32_t i, ecc_flag = 0;
-	uint8_t count, err = 0;
+	uint8_t count;
 	uint32_t byte_pos, bit_pos;
+	int err = 0;
 
 	/* check calculated ecc */
 	for (i = 0; i < ecc->bytes && !ecc_flag; i++) {
@@ -443,6 +441,115 @@ static int omap_correct_data_bch(struct mtd_info *mtd, uint8_t *dat,
 	return (err) ? err : error_count;
 }
 
+#ifdef CONFIG_NAND_OMAP_GPMC_PREFETCH
+
+#define PREFETCH_CONFIG1_CS_SHIFT	24
+#define PREFETCH_FIFOTHRESHOLD_MAX	0x40
+#define PREFETCH_FIFOTHRESHOLD(val)	((val) << 8)
+#define PREFETCH_STATUS_COUNT(val)	(val & 0x00003fff)
+#define PREFETCH_STATUS_FIFO_CNT(val)	((val >> 24) & 0x7F)
+#define ENABLE_PREFETCH			(1 << 7)
+
+/**
+ * omap_prefetch_enable - configures and starts prefetch transfer
+ * @fifo_th: fifo threshold to be used for read/ write
+ * @count: number of bytes to be transferred
+ * @is_write: prefetch read(0) or write post(1) mode
+ * @cs: chip select to use
+ */
+static int omap_prefetch_enable(int fifo_th, unsigned int count, int is_write, int cs)
+{
+	uint32_t val;
+
+	if (fifo_th > PREFETCH_FIFOTHRESHOLD_MAX)
+		return -EINVAL;
+
+	if (readl(&gpmc_cfg->prefetch_control))
+		return -EBUSY;
+
+	/* Set the amount of bytes to be prefetched */
+	writel(count, &gpmc_cfg->prefetch_config2);
+
+	val = (cs << PREFETCH_CONFIG1_CS_SHIFT) | (is_write & 1) |
+		PREFETCH_FIFOTHRESHOLD(fifo_th) | ENABLE_PREFETCH;
+	writel(val, &gpmc_cfg->prefetch_config1);
+
+	/*  Start the prefetch engine */
+	writel(1, &gpmc_cfg->prefetch_control);
+
+	return 0;
+}
+
+/**
+ * omap_prefetch_reset - disables and stops the prefetch engine
+ */
+static void omap_prefetch_reset(void)
+{
+	writel(0, &gpmc_cfg->prefetch_control);
+	writel(0, &gpmc_cfg->prefetch_config1);
+}
+
+static int __read_prefetch_aligned(struct nand_chip *chip, uint32_t *buf, int len)
+{
+	int ret;
+	uint32_t cnt;
+	struct omap_nand_info *info = chip->priv;
+
+	ret = omap_prefetch_enable(PREFETCH_FIFOTHRESHOLD_MAX, len, 0, info->cs);
+	if (ret < 0)
+		return ret;
+
+	do {
+		int i;
+
+		cnt = readl(&gpmc_cfg->prefetch_status);
+		cnt = PREFETCH_STATUS_FIFO_CNT(cnt);
+
+		for (i = 0; i < cnt / 4; i++) {
+			*buf++ = readl(CONFIG_SYS_NAND_BASE);
+			len -= 4;
+		}
+	} while (len);
+
+	omap_prefetch_reset();
+
+	return 0;
+}
+
+static void omap_nand_read_prefetch8(struct mtd_info *mtd, uint8_t *buf, int len)
+{
+	int ret;
+	uint32_t head, tail;
+	struct nand_chip *chip = mtd->priv;
+
+	/*
+	 * If the destination buffer is unaligned, start with reading
+	 * the overlap byte-wise.
+	 */
+	head = ((uint32_t) buf) % 4;
+	if (head) {
+		nand_read_buf(mtd, buf, head);
+		buf += head;
+		len -= head;
+	}
+
+	/*
+	 * Only transfer multiples of 4 bytes in a pre-fetched fashion.
+	 * If there's a residue, care for it byte-wise afterwards.
+	 */
+	tail = len % 4;
+
+	ret = __read_prefetch_aligned(chip, (uint32_t *) buf, len - tail);
+	if (ret < 0) {
+		/* fallback in case the prefetch engine is busy */
+		nand_read_buf(mtd, buf, len);
+	} else if (tail) {
+		buf += len - tail;
+		nand_read_buf(mtd, buf, tail);
+	}
+}
+#endif /* CONFIG_NAND_OMAP_GPMC_PREFETCH */
+
 /**
  * omap_read_page_bch - hardware ecc based page read function
  * @mtd:	mtd info structure
@@ -882,12 +989,15 @@ int board_nand_init(struct nand_chip *nand)
 	if (err)
 		return err;
 
-#ifdef CONFIG_SPL_BUILD
+#ifdef CONFIG_NAND_OMAP_GPMC_PREFETCH
+	/* TODO: Implement for 16-bit bus width */
 	if (nand->options & NAND_BUSWIDTH_16)
 		nand->read_buf = nand_read_buf16;
 	else
-		nand->read_buf = nand_read_buf;
-	nand->dev_ready = omap_spl_dev_ready;
+		nand->read_buf = omap_nand_read_prefetch8;
 #endif
+
+	nand->dev_ready = omap_dev_ready;
+
 	return 0;
 }