From 3a1a344a79de3391f4122975eab1167b641668b9 Mon Sep 17 00:00:00 2001 From: Ezequiel Garcia Date: Mon, 12 Aug 2013 14:14:50 -0300 Subject: [PATCH] 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 Tested-by: Daniel Mack Signed-off-by: Brian Norris Signed-off-by: David Woodhouse --- drivers/mtd/nand/pxa3xx_nand.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/drivers/mtd/nand/pxa3xx_nand.c b/drivers/mtd/nand/pxa3xx_nand.c index 6e28121d3118..b3fc146cdccf 100644 --- a/drivers/mtd/nand/pxa3xx_nand.c +++ b/drivers/mtd/nand/pxa3xx_nand.c @@ -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; }