From mboxrd@z Thu Jan 1 00:00:00 1970 From: marek.vasut@gmail.com (Marek Vasut) Date: Fri, 30 Dec 2011 15:01:07 +0100 Subject: [PATCH v2] MTD/GPMI bugfix : reset the BCH module when it is not MX23 In-Reply-To: <1325233646-3343-1-git-send-email-b32955@freescale.com> References: <1325233646-3343-1-git-send-email-b32955@freescale.com> Message-ID: <201112301501.07351.marek.vasut@gmail.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org > In MX28, if we do not reset the BCH module. The BCH module may > becomes unstable when the board reboots for several thousands times. > This bug has been catched in customer's production. > > The patch adds some comments, and fixes it now. > > Also change gpmi_reset_block() to static. > > Signed-off-by: Huang Shijie > --- > drivers/mtd/nand/gpmi-nand/gpmi-lib.c | 10 +++++++--- > 1 files changed, 7 insertions(+), 3 deletions(-) > > diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c > b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c index de4db76..1573e99 100644 > --- a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c > +++ b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c > @@ -69,7 +69,8 @@ static int clear_poll_bit(void __iomem *addr, u32 mask) > * [1] enable the module. > * [2] reset the module. > * > - * In most of the cases, it's ok. But there is a hardware bug in the BCH > block. + * In most of the cases, it's ok. > + * But in MX23, there is a hardware bug in the BCH block. > * If you try to soft reset the BCH block, it becomes unusable until > * the next hard reset. This case occurs in the NAND boot mode. When the > board * boots by NAND, the ROM of the chip will initialize the BCH blocks > itself. @@ -78,8 +79,10 @@ static int clear_poll_bit(void __iomem *addr, > u32 mask) * > * To avoid this bug, just add a new parameter `just_enable` for > * the mxs_reset_block(), and rewrite it here. > + * > + * The bug has been fixed in the following chips, such as MX28. > */ > -int gpmi_reset_block(void __iomem *reset_addr, bool just_enable) > +static int gpmi_reset_block(void __iomem *reset_addr, bool just_enable) > { > int ret; > int timeout = 0x400; > @@ -206,7 +209,8 @@ int bch_set_geometry(struct gpmi_nand_data *this) > if (ret) > goto err_out; > > - ret = gpmi_reset_block(r->bch_regs, true); > + /* The bug only exits in mx23, the following chips fix it. */ > + ret = gpmi_reset_block(r->bch_regs, GPMI_IS_MX23(this)); > if (ret) > goto err_out; Looks sane, though I can't test right now. Acked-by: Marek Vasut