[PATCH 2/8] sunxi: SPL SPI: add support for read command with 2 byte address

[Samuel Holland]

On 10/13/22 22:05, Icenowy Zheng wrote:
> This kind of read command is utilized in SPI NANDs for reading data
> inside a selected page, which is obviously smaller than how much 2
> byte address can address. So 2 bytes are used for the address and one
> dummy byte is needed after the real address. As the address is sent out
> in bit endian, this makes it not compatible with usual 3 byte address.

typo: big

> Signed-off-by: Icenowy Zheng <uwu at icenowy.me>
> ---
>  arch/arm/mach-sunxi/spl_spi_sunxi.c | 20 +++++++++++++-------
>  1 file changed, 13 insertions(+), 7 deletions(-)

Reviewed-by: Samuel Holland <samuel at sholland.org>
Tested-by: Samuel Holland <samuel at sholland.org> # Orange Pi Zero Plus

> diff --git a/arch/arm/mach-sunxi/spl_spi_sunxi.c b/arch/arm/mach-sunxi/spl_spi_sunxi.c
> index 7975457758..88c15a3ee9 100644
> --- a/arch/arm/mach-sunxi/spl_spi_sunxi.c
> +++ b/arch/arm/mach-sunxi/spl_spi_sunxi.c
> @@ -305,7 +305,7 @@ static void spi0_xfer(const u8 *txbuf, u32 txlen, u8 *rxbuf, u32 rxlen)
>  	}
>  }
>  
> -static void spi0_read_data(void *buf, u32 addr, u32 len)
> +static void spi0_read_data(void *buf, u32 addr, u32 len, u32 addr_len)
>  {
>  	u8 *buf8 = buf;
>  	u32 chunk_len;
> @@ -316,9 +316,15 @@ static void spi0_read_data(void *buf, u32 addr, u32 len)
>  
>  		/* Configure the Read Data Bytes (03h) command header */
>  		txbuf[0] = 0x03;
> -		txbuf[1] = (u8)(addr >> 16);
> -		txbuf[2] = (u8)(addr >> 8);
> -		txbuf[3] = (u8)(addr);
> +		if (addr_len == 3) {
> +			txbuf[1] = (u8)(addr >> 16);
> +			txbuf[2] = (u8)(addr >> 8);
> +			txbuf[3] = (u8)(addr);
> +		} else if (addr_len == 2) {
> +			txbuf[1] = (u8)(addr >> 8);
> +			txbuf[2] = (u8)(addr);
> +			txbuf[3] = 0; /* dummy */
> +		}
>  
>  		if (chunk_len > SPI_READ_MAX_SIZE)
>  			chunk_len = SPI_READ_MAX_SIZE;
> @@ -337,7 +343,7 @@ static void spi0_read_data(void *buf, u32 addr, u32 len)
>  static ulong spi_load_read(struct spl_load_info *load, ulong sector,
>  			   ulong count, void *buf)
>  {
> -	spi0_read_data(buf, sector, count);
> +	spi0_read_data(buf, sector, count, 3);
>  
>  	return count;
>  }
> @@ -356,7 +362,7 @@ static int spl_spi_load_image(struct spl_image_info *spl_image,
>  
>  	spi0_init();
>  
> -	spi0_read_data((void *)header, load_offset, 0x40);
> +	spi0_read_data((void *)header, load_offset, 0x40, 3);
>  
>          if (IS_ENABLED(CONFIG_SPL_LOAD_FIT) &&
>  		image_get_magic(header) == FDT_MAGIC) {
> @@ -376,7 +382,7 @@ static int spl_spi_load_image(struct spl_image_info *spl_image,
>  			return ret;
>  
>  		spi0_read_data((void *)spl_image->load_addr,
> -			       load_offset, spl_image->size);
> +			       load_offset, spl_image->size, 3);
>  	}
>  
>  	spi0_deinit();