mtd: nand: pxa3xx: Support command buffer #3

Some newer controllers support a fourth command buffer. This additional
command buffer allows to set an arbitrary length count, using the
NDCB3.NDLENCNT field, to perform non-standard length operations
such as the ONFI parameter page read.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
This commit is contained in:
Ezequiel Garcia 2013-08-12 14:14:50 -03:00 committed by David Woodhouse
parent 5bb653e890
commit 3a1a344a79

View File

@ -197,6 +197,7 @@ struct pxa3xx_nand_info {
uint32_t ndcb0;
uint32_t ndcb1;
uint32_t ndcb2;
uint32_t ndcb3;
};
static bool use_dma = 1;
@ -493,9 +494,22 @@ static irqreturn_t pxa3xx_nand_irq(int irq, void *devid)
nand_writel(info, NDSR, NDSR_WRCMDREQ);
status &= ~NDSR_WRCMDREQ;
info->state = STATE_CMD_HANDLE;
/*
* Command buffer registers NDCB{0-2} (and optionally NDCB3)
* must be loaded by writing directly either 12 or 16
* bytes directly to NDCB0, four bytes at a time.
*
* Direct write access to NDCB1, NDCB2 and NDCB3 is ignored
* but each NDCBx register can be read.
*/
nand_writel(info, NDCB0, info->ndcb0);
nand_writel(info, NDCB0, info->ndcb1);
nand_writel(info, NDCB0, info->ndcb2);
/* NDCB3 register is available in NFCv2 (Armada 370/XP SoC) */
if (info->variant == PXA3XX_NAND_VARIANT_ARMADA370)
nand_writel(info, NDCB0, info->ndcb3);
}
/* clear NDSR to let the controller exit the IRQ */
@ -554,6 +568,7 @@ static int prepare_command_pool(struct pxa3xx_nand_info *info, int command,
default:
info->ndcb1 = 0;
info->ndcb2 = 0;
info->ndcb3 = 0;
break;
}