Re: [U-Boot] [PATCH 3/5] altera_qspi: skip erase if the sector is blank

24 Dec 2015

Hi Marek,
On 2015年12月24日 09:28, Marek Vasut wrote:
...
On Thursday, December 24, 2015 at 01:51:22 AM, Thomas Chou wrote:
...
Skip erase if the sector is blank. The sector erase is slow, and
may take 0.7 sec typically or up to 3 sec worst-case.
Signed-off-by: Thomas Chou thomas@wytron.com.tw
drivers/mtd/altera_qspi.c | 39 +++++++++++++++++++++++++--------------
  1 file changed, 25 insertions(+), 14 deletions(-)

diff --git a/drivers/mtd/altera_qspi.c b/drivers/mtd/altera_qspi.c
index b0d4f2c..8a630a6 100644
--- a/drivers/mtd/altera_qspi.c
+++ b/drivers/mtd/altera_qspi.c
@@ -131,24 +131,35 @@ static int altera_qspi_erase(struct mtd_info *mtd,
struct erase_info *instr) size_t end = addr + len;
   u32 sect;
   u32 stat;

u32 *flash, *last;
instr->state = MTD_ERASING;
addr &= ~(mtd->erasesize - 1); /* get lower aligned address */
while (addr < end) {



sect = addr / mtd->erasesize;


sect <<= 8;


sect |= QUADSPI_MEM_OP_SECTOR_ERASE;


debug("erase %08x\n", sect);


writel(sect, &regs->mem_op);


stat = readl(&regs->isr);


if (stat & QUADSPI_ISR_ILLEGAL_ERASE) {


	/* erase failed, sector might be protected */


	debug("erase %08x fail %x\n", sect, stat);


	writel(stat, &regs->isr); /* clear isr */


	instr->fail_addr = addr;


	instr->state = MTD_ERASE_FAILED;


	mtd_erase_callback(instr);


	return -EIO;




flash = pdata->base + addr;


last = pdata->base + addr + mtd->erasesize;


/* skip erase if sector is blank */


while (flash < last) {


	if (readl(flash) != 0xffffffff)


		break;


	flash++;



Shouldn't $last be divided by 4 ? $flash is u32 * afterall .
No. Both flash and last are assigned with byte addressing from 
pdata->base, which is void *.
Best regards,
Thomas

    