[PATCH fix] mtd: nand: kill the the NAND_MAX_PAGESIZE/NAND_MAX_OOBSIZE for nand_buffers{}
Huang Shijie
b32955 at freescale.com
Mon Jan 13 01:27:12 EST 2014
The patch converts the arrays to buffer pointers for nand_buffers{}.
The cafe_nand.c is the only NAND_OWN_BUFFERS user which allocates
a nand_buffers{} itself.
This patch disables the DMA for nand_scan_ident, and restore the DMA
status after we finish the nand_scan_ident. By this way, we can get the
mtd->writesize and mtd->oobsize, and then allocates the cafe->dmabuf
with them.
Since the cafe_nand.c uses the NAND_ECC_HW_SYNDROME ECC mode, we do not
allocate the buffers for @ecccalc and @ecccode.
Signed-off-by: Huang Shijie <b32955 at freescale.com>
---
fix: Setup the DMA address after we have allocated the DMA buffer.
---
drivers/mtd/nand/cafe_nand.c | 68 ++++++++++++++++++++++++++++-------------
drivers/mtd/nand/nand_base.c | 19 +++++++++--
include/linux/mtd/nand.h | 12 ++++----
3 files changed, 67 insertions(+), 32 deletions(-)
diff --git a/drivers/mtd/nand/cafe_nand.c b/drivers/mtd/nand/cafe_nand.c
index f2f64ad..4e66726 100644
--- a/drivers/mtd/nand/cafe_nand.c
+++ b/drivers/mtd/nand/cafe_nand.c
@@ -627,6 +627,8 @@ static int cafe_nand_probe(struct pci_dev *pdev,
struct cafe_priv *cafe;
uint32_t ctrl;
int err = 0;
+ int old_dma;
+ struct nand_buffers *nbuf;
/* Very old versions shared the same PCI ident for all three
functions on the chip. Verify the class too... */
@@ -655,13 +657,6 @@ static int cafe_nand_probe(struct pci_dev *pdev,
err = -ENOMEM;
goto out_free_mtd;
}
- cafe->dmabuf = dma_alloc_coherent(&cafe->pdev->dev, 2112 + sizeof(struct nand_buffers),
- &cafe->dmaaddr, GFP_KERNEL);
- if (!cafe->dmabuf) {
- err = -ENOMEM;
- goto out_ior;
- }
- cafe->nand.buffers = (void *)cafe->dmabuf + 2112;
cafe->rs = init_rs_non_canonical(12, &cafe_mul, 0, 1, 8);
if (!cafe->rs) {
@@ -721,7 +716,7 @@ static int cafe_nand_probe(struct pci_dev *pdev,
"CAFE NAND", mtd);
if (err) {
dev_warn(&pdev->dev, "Could not register IRQ %d\n", pdev->irq);
- goto out_free_dma;
+ goto out_ior;
}
/* Disable master reset, enable NAND clock */
@@ -735,6 +730,32 @@ static int cafe_nand_probe(struct pci_dev *pdev,
cafe_writel(cafe, 0x7006, GLOBAL_CTRL);
cafe_writel(cafe, 0x700a, GLOBAL_CTRL);
+ /* Enable NAND IRQ in global IRQ mask register */
+ cafe_writel(cafe, 0x80000007, GLOBAL_IRQ_MASK);
+ cafe_dev_dbg(&cafe->pdev->dev, "Control %x, IRQ mask %x\n",
+ cafe_readl(cafe, GLOBAL_CTRL),
+ cafe_readl(cafe, GLOBAL_IRQ_MASK));
+
+ /* Do not use the DMA for the nand_scan_ident() */
+ old_dma = usedma;
+ usedma = 0;
+
+ /* Scan to find existence of the device */
+ if (nand_scan_ident(mtd, 2, NULL)) {
+ err = -ENXIO;
+ goto out_irq;
+ }
+
+ cafe->dmabuf = dma_alloc_coherent(&cafe->pdev->dev,
+ 2112 + sizeof(struct nand_buffers) +
+ mtd->writesize + mtd->oobsize,
+ &cafe->dmaaddr, GFP_KERNEL);
+ if (!cafe->dmabuf) {
+ err = -ENOMEM;
+ goto out_irq;
+ }
+ cafe->nand.buffers = nbuf = (void *)cafe->dmabuf + 2112;
+
/* Set up DMA address */
cafe_writel(cafe, cafe->dmaaddr & 0xffffffff, NAND_DMA_ADDR0);
if (sizeof(cafe->dmaaddr) > 4)
@@ -746,16 +767,13 @@ static int cafe_nand_probe(struct pci_dev *pdev,
cafe_dev_dbg(&cafe->pdev->dev, "Set DMA address to %x (virt %p)\n",
cafe_readl(cafe, NAND_DMA_ADDR0), cafe->dmabuf);
- /* Enable NAND IRQ in global IRQ mask register */
- cafe_writel(cafe, 0x80000007, GLOBAL_IRQ_MASK);
- cafe_dev_dbg(&cafe->pdev->dev, "Control %x, IRQ mask %x\n",
- cafe_readl(cafe, GLOBAL_CTRL), cafe_readl(cafe, GLOBAL_IRQ_MASK));
+ /* this driver does not need the @ecccalc and @ecccode */
+ nbuf->ecccalc = NULL;
+ nbuf->ecccode = NULL;
+ nbuf->databuf = (uint8_t *)(nbuf + 1);
- /* Scan to find existence of the device */
- if (nand_scan_ident(mtd, 2, NULL)) {
- err = -ENXIO;
- goto out_irq;
- }
+ /* Restore the DMA flag */
+ usedma = old_dma;
cafe->ctl2 = 1<<27; /* Reed-Solomon ECC */
if (mtd->writesize == 2048)
@@ -773,7 +791,7 @@ static int cafe_nand_probe(struct pci_dev *pdev,
} else {
printk(KERN_WARNING "Unexpected NAND flash writesize %d. Aborting\n",
mtd->writesize);
- goto out_irq;
+ goto out_free_dma;
}
cafe->nand.ecc.mode = NAND_ECC_HW_SYNDROME;
cafe->nand.ecc.size = mtd->writesize;
@@ -790,7 +808,7 @@ static int cafe_nand_probe(struct pci_dev *pdev,
err = nand_scan_tail(mtd);
if (err)
- goto out_irq;
+ goto out_free_dma;
pci_set_drvdata(pdev, mtd);
@@ -799,12 +817,15 @@ static int cafe_nand_probe(struct pci_dev *pdev,
goto out;
+ out_free_dma:
+ dma_free_coherent(&cafe->pdev->dev,
+ 2112 + sizeof(struct nand_buffers) +
+ mtd->writesize + mtd->oobsize,
+ cafe->dmabuf, cafe->dmaaddr);
out_irq:
/* Disable NAND IRQ in global IRQ mask register */
cafe_writel(cafe, ~1 & cafe_readl(cafe, GLOBAL_IRQ_MASK), GLOBAL_IRQ_MASK);
free_irq(pdev->irq, mtd);
- out_free_dma:
- dma_free_coherent(&cafe->pdev->dev, 2112, cafe->dmabuf, cafe->dmaaddr);
out_ior:
pci_iounmap(pdev, cafe->mmio);
out_free_mtd:
@@ -824,7 +845,10 @@ static void cafe_nand_remove(struct pci_dev *pdev)
nand_release(mtd);
free_rs(cafe->rs);
pci_iounmap(pdev, cafe->mmio);
- dma_free_coherent(&cafe->pdev->dev, 2112, cafe->dmabuf, cafe->dmaaddr);
+ dma_free_coherent(&cafe->pdev->dev,
+ 2112 + sizeof(struct nand_buffers) +
+ mtd->writesize + mtd->oobsize,
+ cafe->dmabuf, cafe->dmaaddr);
kfree(mtd);
}
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index dd22cc4..21e1746 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -3733,15 +3733,26 @@ int nand_scan_tail(struct mtd_info *mtd)
int i;
struct nand_chip *chip = mtd->priv;
struct nand_ecc_ctrl *ecc = &chip->ecc;
+ struct nand_buffers *nbuf;
/* New bad blocks should be marked in OOB, flash-based BBT, or both */
BUG_ON((chip->bbt_options & NAND_BBT_NO_OOB_BBM) &&
!(chip->bbt_options & NAND_BBT_USE_FLASH));
- if (!(chip->options & NAND_OWN_BUFFERS))
- chip->buffers = kmalloc(sizeof(*chip->buffers), GFP_KERNEL);
- if (!chip->buffers)
- return -ENOMEM;
+ if (!(chip->options & NAND_OWN_BUFFERS)) {
+ nbuf = kzalloc(sizeof(*nbuf) + mtd->writesize
+ + mtd->oobsize * 3, GFP_KERNEL);
+ if (!nbuf)
+ return -ENOMEM;
+ nbuf->ecccalc = (uint8_t *)(nbuf + 1);
+ nbuf->ecccode = nbuf->ecccalc + mtd->oobsize;
+ nbuf->databuf = nbuf->ecccode + mtd->oobsize;
+
+ chip->buffers = nbuf;
+ } else {
+ if (!chip->buffers)
+ return -ENOMEM;
+ }
/* Set the internal oob buffer location, just after the page data */
chip->oob_poi = chip->buffers->databuf + mtd->writesize;
diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
index d06a56a..773bd93 100644
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h
@@ -481,17 +481,17 @@ struct nand_ecc_ctrl {
/**
* struct nand_buffers - buffer structure for read/write
- * @ecccalc: buffer for calculated ECC
- * @ecccode: buffer for ECC read from flash
- * @databuf: buffer for data - dynamically sized
+ * @ecccalc: buffer pointer for calculated ECC, size is oobsize.
+ * @ecccode: buffer pointer for ECC read from flash, size is oobsize.
+ * @databuf: buffer pointer for data, size is (page size + oobsize).
*
* Do not change the order of buffers. databuf and oobrbuf must be in
* consecutive order.
*/
struct nand_buffers {
- uint8_t ecccalc[NAND_MAX_OOBSIZE];
- uint8_t ecccode[NAND_MAX_OOBSIZE];
- uint8_t databuf[NAND_MAX_PAGESIZE + NAND_MAX_OOBSIZE];
+ uint8_t *ecccalc;
+ uint8_t *ecccode;
+ uint8_t *databuf;
};
/**
--
1.7.2.rc3
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