JZ_REG_NAND_IRQ_STAT
status = readl(ecc->base + JZ_REG_NAND_IRQ_STAT);
writel(0, ecc->base + JZ_REG_NAND_IRQ_STAT);
writel(0, ecc->base + JZ_REG_NAND_IRQ_STAT);
status = readl(ecc->base + JZ_REG_NAND_IRQ_STAT);