[PATCH v2 1/2] mtd: brcmnand: iProc big endian and ONFI support

[boris.brezillon@free-electrons.com (Boris Brezillon)]

On Wed, 20 Jul 2016 14:53:50 -0700
Ray Jui <ray.jui@broadcom.com> wrote:

> This patch adds big endian and ONFI support for various iProc based
> SoCs that use the core brcmstb NAND controller

Brian, Kamal, can you review this patch?

> 
> This patch was originally implemented by Prafulla Kota
> <prafulla.kota@broadcom.com> and fully tested on iProc based NS2 SVK
> 
> Signed-off-by: Prafulla Kota <prafulla.kota@broadcom.com>
> Signed-off-by: Ray Jui <ray.jui@broadcom.com>
> ---
>  drivers/mtd/nand/brcmnand/brcmnand.c   | 12 ++++++------
>  drivers/mtd/nand/brcmnand/brcmnand.h   | 13 ++++++++-----
>  drivers/mtd/nand/brcmnand/iproc_nand.c | 18 ++++++++++++++----
>  3 files changed, 28 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/mtd/nand/brcmnand/brcmnand.c b/drivers/mtd/nand/brcmnand/brcmnand.c
> index b76ad7c..12a1585 100644
> --- a/drivers/mtd/nand/brcmnand/brcmnand.c
> +++ b/drivers/mtd/nand/brcmnand/brcmnand.c
> @@ -1279,7 +1279,7 @@ static void brcmnand_cmdfunc(struct mtd_info *mtd, unsigned command,
>  		u32 *flash_cache = (u32 *)ctrl->flash_cache;
>  		int i;
>  
> -		brcmnand_soc_data_bus_prepare(ctrl->soc);
> +		brcmnand_soc_data_bus_prepare(ctrl->soc, true);
>  
>  		/*
>  		 * Must cache the FLASH_CACHE now, since changes in
> @@ -1292,7 +1292,7 @@ static void brcmnand_cmdfunc(struct mtd_info *mtd, unsigned command,
>  			 */
>  			flash_cache[i] = be32_to_cpu(brcmnand_read_fc(ctrl, i));
>  
> -		brcmnand_soc_data_bus_unprepare(ctrl->soc);
> +		brcmnand_soc_data_bus_unprepare(ctrl->soc, true);
>  
>  		/* Cleanup from HW quirk: restore SECTOR_SIZE_1K */
>  		if (host->hwcfg.sector_size_1k)
> @@ -1508,12 +1508,12 @@ static int brcmnand_read_by_pio(struct mtd_info *mtd, struct nand_chip *chip,
>  		brcmnand_waitfunc(mtd, chip);
>  
>  		if (likely(buf)) {
> -			brcmnand_soc_data_bus_prepare(ctrl->soc);
> +			brcmnand_soc_data_bus_prepare(ctrl->soc, false);
>  
>  			for (j = 0; j < FC_WORDS; j++, buf++)
>  				*buf = brcmnand_read_fc(ctrl, j);
>  
> -			brcmnand_soc_data_bus_unprepare(ctrl->soc);
> +			brcmnand_soc_data_bus_unprepare(ctrl->soc, false);
>  		}
>  
>  		if (oob)
> @@ -1678,12 +1678,12 @@ static int brcmnand_write(struct mtd_info *mtd, struct nand_chip *chip,
>  		(void)brcmnand_read_reg(ctrl, BRCMNAND_CMD_ADDRESS);
>  
>  		if (buf) {
> -			brcmnand_soc_data_bus_prepare(ctrl->soc);
> +			brcmnand_soc_data_bus_prepare(ctrl->soc, false);
>  
>  			for (j = 0; j < FC_WORDS; j++, buf++)
>  				brcmnand_write_fc(ctrl, j, *buf);
>  
> -			brcmnand_soc_data_bus_unprepare(ctrl->soc);
> +			brcmnand_soc_data_bus_unprepare(ctrl->soc, false);
>  		} else if (oob) {
>  			for (j = 0; j < FC_WORDS; j++)
>  				brcmnand_write_fc(ctrl, j, 0xffffffff);
> diff --git a/drivers/mtd/nand/brcmnand/brcmnand.h b/drivers/mtd/nand/brcmnand/brcmnand.h
> index ef5eabb..5c44cd4 100644
> --- a/drivers/mtd/nand/brcmnand/brcmnand.h
> +++ b/drivers/mtd/nand/brcmnand/brcmnand.h
> @@ -23,19 +23,22 @@ struct dev_pm_ops;
>  struct brcmnand_soc {
>  	bool (*ctlrdy_ack)(struct brcmnand_soc *soc);
>  	void (*ctlrdy_set_enabled)(struct brcmnand_soc *soc, bool en);
> -	void (*prepare_data_bus)(struct brcmnand_soc *soc, bool prepare);
> +	void (*prepare_data_bus)(struct brcmnand_soc *soc, bool prepare,
> +				 bool is_param);
>  };
>  
> -static inline void brcmnand_soc_data_bus_prepare(struct brcmnand_soc *soc)
> +static inline void brcmnand_soc_data_bus_prepare(struct brcmnand_soc *soc,
> +						 bool is_param)
>  {
>  	if (soc && soc->prepare_data_bus)
> -		soc->prepare_data_bus(soc, true);
> +		soc->prepare_data_bus(soc, true, is_param);
>  }
>  
> -static inline void brcmnand_soc_data_bus_unprepare(struct brcmnand_soc *soc)
> +static inline void brcmnand_soc_data_bus_unprepare(struct brcmnand_soc *soc,
> +						   bool is_param)
>  {
>  	if (soc && soc->prepare_data_bus)
> -		soc->prepare_data_bus(soc, false);
> +		soc->prepare_data_bus(soc, false, is_param);
>  }
>  
>  static inline u32 brcmnand_readl(void __iomem *addr)
> diff --git a/drivers/mtd/nand/brcmnand/iproc_nand.c b/drivers/mtd/nand/brcmnand/iproc_nand.c
> index 585596c..4c6ae11 100644
> --- a/drivers/mtd/nand/brcmnand/iproc_nand.c
> +++ b/drivers/mtd/nand/brcmnand/iproc_nand.c
> @@ -74,7 +74,8 @@ static void iproc_nand_intc_set(struct brcmnand_soc *soc, bool en)
>  	spin_unlock_irqrestore(&priv->idm_lock, flags);
>  }
>  
> -static void iproc_nand_apb_access(struct brcmnand_soc *soc, bool prepare)
> +static void iproc_nand_apb_access(struct brcmnand_soc *soc, bool prepare,
> +				  bool is_param)
>  {
>  	struct iproc_nand_soc *priv =
>  			container_of(soc, struct iproc_nand_soc, soc);
> @@ -86,10 +87,19 @@ static void iproc_nand_apb_access(struct brcmnand_soc *soc, bool prepare)
>  
>  	val = brcmnand_readl(mmio);
>  
> -	if (prepare)
> -		val |= IPROC_NAND_APB_LE_MODE;
> -	else
> +	/*
> +	 * In the case of BE or when dealing with NAND data, alway configure
> +	 * the APB bus to LE mode before accessing the FIFO and back to BE mode
> +	 * after the access is done
> +	 */
> +	if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN) || !is_param) {
> +		if (prepare)
> +			val |= IPROC_NAND_APB_LE_MODE;
> +		else
> +			val &= ~IPROC_NAND_APB_LE_MODE;
> +	} else { /* when in LE accessing the parameter page, keep APB in BE */
>  		val &= ~IPROC_NAND_APB_LE_MODE;
> +	}
>  
>  	brcmnand_writel(val, mmio);
>