From a47bfd2eb66837653dc3b42541dfe4283dd41251 Mon Sep 17 00:00:00 2001 From: Ivo Clarysse Date: Thu, 8 Apr 2010 16:16:51 +0200 Subject: [PATCH] mtd: mxc_nand: support i.MX21 On i.MX21 SoCs, if the NFC_CONFIG1:NFC_INT_MASK bit is set, NFC_CONFIG2:NFC_INT always reads out zero, even if an operation is completed. This patch uses enable_irq and disable_irq_nosync instead of NFC_CONFIG1:NFC_INT_MASK to mask NFC interrupts. This allows NFC_CONFIG2:NFC_INT to also be used to detect operation completion on i.MX21. The i.MX21 NFC does not signal reset completion using NFC_CONFIG1:NFC_INT_MASK, so instead reset completion is tested by checking if NFC_CONFIG2 becomes 0. Signed-off-by: Ivo Clarysse Acked-by: Sascha Hauer Signed-off-by: David Woodhouse --- drivers/mtd/nand/mxc_nand.c | 41 ++++++++++++++++++++++--------------- 1 file changed, 25 insertions(+), 16 deletions(-) diff --git a/drivers/mtd/nand/mxc_nand.c b/drivers/mtd/nand/mxc_nand.c index b527aa2d687d..35da3dc4bd17 100644 --- a/drivers/mtd/nand/mxc_nand.c +++ b/drivers/mtd/nand/mxc_nand.c @@ -38,7 +38,7 @@ #define DRIVER_NAME "mxc_nand" #define nfc_is_v21() (cpu_is_mx25() || cpu_is_mx35()) -#define nfc_is_v1() (cpu_is_mx31() || cpu_is_mx27()) +#define nfc_is_v1() (cpu_is_mx31() || cpu_is_mx27() || cpu_is_mx21()) /* Addresses for NFC registers */ #define NFC_BUF_SIZE 0xE00 @@ -168,11 +168,7 @@ static irqreturn_t mxc_nfc_irq(int irq, void *dev_id) { struct mxc_nand_host *host = dev_id; - uint16_t tmp; - - tmp = readw(host->regs + NFC_CONFIG1); - tmp |= NFC_INT_MSK; /* Disable interrupt */ - writew(tmp, host->regs + NFC_CONFIG1); + disable_irq_nosync(irq); wake_up(&host->irq_waitq); @@ -184,15 +180,13 @@ static irqreturn_t mxc_nfc_irq(int irq, void *dev_id) */ static void wait_op_done(struct mxc_nand_host *host, int useirq) { - uint32_t tmp; - int max_retries = 2000; + uint16_t tmp; + int max_retries = 8000; if (useirq) { if ((readw(host->regs + NFC_CONFIG2) & NFC_INT) == 0) { - tmp = readw(host->regs + NFC_CONFIG1); - tmp &= ~NFC_INT_MSK; /* Enable interrupt */ - writew(tmp, host->regs + NFC_CONFIG1); + enable_irq(host->irq); wait_event(host->irq_waitq, readw(host->regs + NFC_CONFIG2) & NFC_INT); @@ -226,8 +220,23 @@ static void send_cmd(struct mxc_nand_host *host, uint16_t cmd, int useirq) writew(cmd, host->regs + NFC_FLASH_CMD); writew(NFC_CMD, host->regs + NFC_CONFIG2); - /* Wait for operation to complete */ - wait_op_done(host, useirq); + if (cpu_is_mx21() && (cmd == NAND_CMD_RESET)) { + int max_retries = 100; + /* Reset completion is indicated by NFC_CONFIG2 */ + /* being set to 0 */ + while (max_retries-- > 0) { + if (readw(host->regs + NFC_CONFIG2) == 0) { + break; + } + udelay(1); + } + if (max_retries < 0) + DEBUG(MTD_DEBUG_LEVEL0, "%s: RESET failed\n", + __func__); + } else { + /* Wait for operation to complete */ + wait_op_done(host, useirq); + } } /* This function sends an address (or partial address) to the @@ -548,9 +557,9 @@ static void preset(struct mtd_info *mtd) struct mxc_nand_host *host = nand_chip->priv; uint16_t tmp; - /* disable interrupt, disable spare enable */ + /* enable interrupt, disable spare enable */ tmp = readw(host->regs + NFC_CONFIG1); - tmp |= NFC_INT_MSK; + tmp &= ~NFC_INT_MSK; tmp &= ~NFC_SP_EN; if (nand_chip->ecc.mode == NAND_ECC_HW) { tmp |= NFC_ECC_EN; @@ -820,7 +829,7 @@ static int __init mxcnd_probe(struct platform_device *pdev) host->irq = platform_get_irq(pdev, 0); - err = request_irq(host->irq, mxc_nfc_irq, 0, DRIVER_NAME, host); + err = request_irq(host->irq, mxc_nfc_irq, IRQF_DISABLED, DRIVER_NAME, host); if (err) goto eirq; -- 2.39.5