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author | Sukumar Ghorai <s-ghorai@ti.com> | 2011-01-28 10:12:06 (GMT) |
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committer | Tony Lindgren <tony@atomide.com> | 2011-02-17 23:32:53 (GMT) |
commit | 4e070376165a9b7f245fada77645b81352c6ec78 (patch) | |
tree | 76a854fc37f50633f10a9eb25382d43329a94083 /drivers/mtd/nand/omap2.c | |
parent | db97eb7dfe13f6c04f0a0e77c32e2691f563ab8b (diff) | |
download | linux-fsl-qoriq-4e070376165a9b7f245fada77645b81352c6ec78.tar.xz |
omap3: nand: prefetch in irq mode support
This patch enable prefetch-irq mode for nand transfer(read, write)
Signed-off-by: Vimal Singh <vimalsingh@ti.com>
Signed-off-by: Sukumar Ghorai <s-ghorai@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Diffstat (limited to 'drivers/mtd/nand/omap2.c')
-rw-r--r-- | drivers/mtd/nand/omap2.c | 198 |
1 files changed, 189 insertions, 9 deletions
diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c index 60bac8e..fbe8414 100644 --- a/drivers/mtd/nand/omap2.c +++ b/drivers/mtd/nand/omap2.c @@ -11,6 +11,7 @@ #include <linux/platform_device.h> #include <linux/dma-mapping.h> #include <linux/delay.h> +#include <linux/interrupt.h> #include <linux/jiffies.h> #include <linux/sched.h> #include <linux/mtd/mtd.h> @@ -24,6 +25,7 @@ #include <plat/nand.h> #define DRIVER_NAME "omap2-nand" +#define OMAP_NAND_TIMEOUT_MS 5000 #define NAND_Ecc_P1e (1 << 0) #define NAND_Ecc_P2e (1 << 1) @@ -108,6 +110,13 @@ struct omap_nand_info { unsigned long phys_base; struct completion comp; int dma_ch; + int gpmc_irq; + enum { + OMAP_NAND_IO_READ = 0, /* read */ + OMAP_NAND_IO_WRITE, /* write */ + } iomode; + u_char *buf; + int buf_len; }; /** @@ -267,9 +276,10 @@ static void omap_write_buf_pref(struct mtd_info *mtd, { struct omap_nand_info *info = container_of(mtd, struct omap_nand_info, mtd); - uint32_t pref_count = 0, w_count = 0; + uint32_t w_count = 0; int i = 0, ret = 0; u16 *p; + unsigned long tim, limit; /* take care of subpage writes */ if (len % 2 != 0) { @@ -295,9 +305,12 @@ static void omap_write_buf_pref(struct mtd_info *mtd, iowrite16(*p++, info->nand.IO_ADDR_W); } /* wait for data to flushed-out before reset the prefetch */ - do { - pref_count = gpmc_read_status(GPMC_PREFETCH_COUNT); - } while (pref_count); + tim = 0; + limit = (loops_per_jiffy * + msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS)); + while (gpmc_read_status(GPMC_PREFETCH_COUNT) && (tim++ < limit)) + cpu_relax(); + /* disable and stop the PFPW engine */ gpmc_prefetch_reset(info->gpmc_cs); } @@ -326,11 +339,11 @@ static inline int omap_nand_dma_transfer(struct mtd_info *mtd, void *addr, { struct omap_nand_info *info = container_of(mtd, struct omap_nand_info, mtd); - uint32_t prefetch_status = 0; enum dma_data_direction dir = is_write ? DMA_TO_DEVICE : DMA_FROM_DEVICE; dma_addr_t dma_addr; int ret; + unsigned long tim, limit; /* The fifo depth is 64 bytes. We have a sync at each frame and frame * length is 64 bytes. @@ -376,7 +389,7 @@ static inline int omap_nand_dma_transfer(struct mtd_info *mtd, void *addr, /* configure and start prefetch transfer */ ret = gpmc_prefetch_enable(info->gpmc_cs, 0x1, len, is_write); if (ret) - /* PFPW engine is busy, use cpu copy methode */ + /* PFPW engine is busy, use cpu copy method */ goto out_copy; init_completion(&info->comp); @@ -385,10 +398,11 @@ static inline int omap_nand_dma_transfer(struct mtd_info *mtd, void *addr, /* setup and start DMA using dma_addr */ wait_for_completion(&info->comp); + tim = 0; + limit = (loops_per_jiffy * msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS)); + while (gpmc_read_status(GPMC_PREFETCH_COUNT) && (tim++ < limit)) + cpu_relax(); - do { - prefetch_status = gpmc_read_status(GPMC_PREFETCH_COUNT); - } while (prefetch_status); /* disable and stop the PFPW engine */ gpmc_prefetch_reset(info->gpmc_cs); @@ -436,6 +450,155 @@ static void omap_write_buf_dma_pref(struct mtd_info *mtd, omap_nand_dma_transfer(mtd, (u_char *) buf, len, 0x1); } +/* + * omap_nand_irq - GMPC irq handler + * @this_irq: gpmc irq number + * @dev: omap_nand_info structure pointer is passed here + */ +static irqreturn_t omap_nand_irq(int this_irq, void *dev) +{ + struct omap_nand_info *info = (struct omap_nand_info *) dev; + u32 bytes; + u32 irq_stat; + + irq_stat = gpmc_read_status(GPMC_GET_IRQ_STATUS); + bytes = gpmc_read_status(GPMC_PREFETCH_FIFO_CNT); + bytes = bytes & 0xFFFC; /* io in multiple of 4 bytes */ + if (info->iomode == OMAP_NAND_IO_WRITE) { /* checks for write io */ + if (irq_stat & 0x2) + goto done; + + if (info->buf_len && (info->buf_len < bytes)) + bytes = info->buf_len; + else if (!info->buf_len) + bytes = 0; + iowrite32_rep(info->nand.IO_ADDR_W, + (u32 *)info->buf, bytes >> 2); + info->buf = info->buf + bytes; + info->buf_len -= bytes; + + } else { + ioread32_rep(info->nand.IO_ADDR_R, + (u32 *)info->buf, bytes >> 2); + info->buf = info->buf + bytes; + + if (irq_stat & 0x2) + goto done; + } + gpmc_cs_configure(info->gpmc_cs, GPMC_SET_IRQ_STATUS, irq_stat); + + return IRQ_HANDLED; + +done: + complete(&info->comp); + /* disable irq */ + gpmc_cs_configure(info->gpmc_cs, GPMC_ENABLE_IRQ, 0); + + /* clear status */ + gpmc_cs_configure(info->gpmc_cs, GPMC_SET_IRQ_STATUS, irq_stat); + + return IRQ_HANDLED; +} + +/* + * omap_read_buf_irq_pref - read data from NAND controller into buffer + * @mtd: MTD device structure + * @buf: buffer to store date + * @len: number of bytes to read + */ +static void omap_read_buf_irq_pref(struct mtd_info *mtd, u_char *buf, int len) +{ + struct omap_nand_info *info = container_of(mtd, + struct omap_nand_info, mtd); + int ret = 0; + + if (len <= mtd->oobsize) { + omap_read_buf_pref(mtd, buf, len); + return; + } + + info->iomode = OMAP_NAND_IO_READ; + info->buf = buf; + init_completion(&info->comp); + + /* configure and start prefetch transfer */ + ret = gpmc_prefetch_enable(info->gpmc_cs, 0x0, len, 0x0); + if (ret) + /* PFPW engine is busy, use cpu copy method */ + goto out_copy; + + info->buf_len = len; + /* enable irq */ + gpmc_cs_configure(info->gpmc_cs, GPMC_ENABLE_IRQ, + (GPMC_IRQ_FIFOEVENTENABLE | GPMC_IRQ_COUNT_EVENT)); + + /* waiting for read to complete */ + wait_for_completion(&info->comp); + + /* disable and stop the PFPW engine */ + gpmc_prefetch_reset(info->gpmc_cs); + return; + +out_copy: + if (info->nand.options & NAND_BUSWIDTH_16) + omap_read_buf16(mtd, buf, len); + else + omap_read_buf8(mtd, buf, len); +} + +/* + * omap_write_buf_irq_pref - write buffer to NAND controller + * @mtd: MTD device structure + * @buf: data buffer + * @len: number of bytes to write + */ +static void omap_write_buf_irq_pref(struct mtd_info *mtd, + const u_char *buf, int len) +{ + struct omap_nand_info *info = container_of(mtd, + struct omap_nand_info, mtd); + int ret = 0; + unsigned long tim, limit; + + if (len <= mtd->oobsize) { + omap_write_buf_pref(mtd, buf, len); + return; + } + + info->iomode = OMAP_NAND_IO_WRITE; + info->buf = (u_char *) buf; + init_completion(&info->comp); + + /* configure and start prefetch transfer */ + ret = gpmc_prefetch_enable(info->gpmc_cs, 0x0, len, 0x1); + if (ret) + /* PFPW engine is busy, use cpu copy method */ + goto out_copy; + + info->buf_len = len; + /* enable irq */ + gpmc_cs_configure(info->gpmc_cs, GPMC_ENABLE_IRQ, + (GPMC_IRQ_FIFOEVENTENABLE | GPMC_IRQ_COUNT_EVENT)); + + /* waiting for write to complete */ + wait_for_completion(&info->comp); + /* wait for data to flushed-out before reset the prefetch */ + tim = 0; + limit = (loops_per_jiffy * msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS)); + while (gpmc_read_status(GPMC_PREFETCH_COUNT) && (tim++ < limit)) + cpu_relax(); + + /* disable and stop the PFPW engine */ + gpmc_prefetch_reset(info->gpmc_cs); + return; + +out_copy: + if (info->nand.options & NAND_BUSWIDTH_16) + omap_write_buf16(mtd, buf, len); + else + omap_write_buf8(mtd, buf, len); +} + /** * omap_verify_buf - Verify chip data against buffer * @mtd: MTD device structure @@ -846,6 +1009,20 @@ static int __devinit omap_nand_probe(struct platform_device *pdev) } break; + case NAND_OMAP_PREFETCH_IRQ: + err = request_irq(pdata->gpmc_irq, + omap_nand_irq, IRQF_SHARED, "gpmc-nand", info); + if (err) { + dev_err(&pdev->dev, "requesting irq(%d) error:%d", + pdata->gpmc_irq, err); + goto out_release_mem_region; + } else { + info->gpmc_irq = pdata->gpmc_irq; + info->nand.read_buf = omap_read_buf_irq_pref; + info->nand.write_buf = omap_write_buf_irq_pref; + } + break; + default: dev_err(&pdev->dev, "xfer_type(%d) not supported!\n", pdata->xfer_type); @@ -911,6 +1088,9 @@ static int omap_nand_remove(struct platform_device *pdev) if (info->dma_ch != -1) omap_free_dma(info->dma_ch); + if (info->gpmc_irq) + free_irq(info->gpmc_irq, info); + /* Release NAND device, its internal structures and partitions */ nand_release(&info->mtd); iounmap(info->nand.IO_ADDR_R); |