[U-Boot] [PATCH 2/6] sf: Optimize flash features code

[Marek Vasut]

On Saturday, January 18, 2014 at 09:51:56 PM, Jagan Teki wrote:
> On Sun, Jan 19, 2014 at 2:09 AM, Marek Vasut <marex at denx.de> wrote:
> > On Saturday, January 18, 2014 at 09:06:29 PM, Jagannadha Sutradharudu
> > Teki
> > 
> > wrote:
> >> - Shrink spi_slave {}
> >> - Shrink spi_flash_params {}
> >> - Documentation for sf features
> >> 
> >> Signed-off-by: Jagannadha Sutradharudu Teki <jaganna at xilinx.com>
> >> Cc: Marek Vasut <marex at denx.de>
> >> ---
> >> 
> >>  doc/SPI/README.sf-features    | 122 ++++++++++++++++++++++++++++++
> >>  drivers/mtd/spi/sf.c          |   4 +-
> >>  drivers/mtd/spi/sf_internal.h |   1 -
> >>  drivers/mtd/spi/sf_ops.c      |   8 +-
> >>  drivers/mtd/spi/sf_params.c   | 172
> >> 
> >> +++++++++++++++++++++--------------------- drivers/mtd/spi/sf_probe.c   
> >> |
> >> 
> >>  71 ++++++++---------
> >>  include/spi.h                 |  42 ++++-------
> >>  include/spi_flash.h           |  24 +++---
> >>  8 files changed, 270 insertions(+), 174 deletions(-)
> >>  create mode 100644 doc/SPI/README.sf-features
> >> 
> >> diff --git a/doc/SPI/README.sf-features b/doc/SPI/README.sf-features
> >> new file mode 100644
> >> index 0000000..d35f56d
> >> --- /dev/null
> >> +++ b/doc/SPI/README.sf-features
> >> @@ -0,0 +1,122 @@
> >> +SPI FLASH feature enhancements:
> >> +==============================
> >> +
> >> +This document describes how to extend the current data structures in
> >> spi subsystem +for making use of new flash features/operations w.r.t to
> >> controller driver support. +
> >> +1. spi_slave:
> >> +
> >> +struct spi_slave {
> >> +    ..........
> >> +    u32 mode_bits;
> >> +    ........
> >> +};
> >> +
> >> + at mode_bits can be used to expose the SPI RX/TX operation modes, bus
> >> options and +few flags which are used to extended the flash specific
> >> features/operations +- include/spi.h
> >> +
> >> +mode_bits:
> >> +- SPI_TX_QPP: 4-Wire tx transfer operation quad page program
> >> +- SPI_RX_SLOW: 1-wire rx transfer operation array slow read
> >> +- SPI_RX_DUAL: 2-wire rx transfer operation dual fast read
> >> +- SPI_RX_DUAL_IO: 2-wire rx transfer operation dual io fast read
> >> +- SPI_RX_QUAD: 4-wire rx transfer operation quad fast read
> >> +- SPI_RX_QUAD_IO: 4-wire rx transfer operation quad io fast read
> >> +- SPI_SHARED: dual flash devices are connected in shared bus connection
> >> +- SPI_SEPARATED: dual flash devices are connected in separate bus
> >> connection +- SPI_U_PAGE: select the upper flash in dual flash shared
> >> bus connection [1] +
> > 
> > A generic SPI controller _does_ _not_ _care_ about any SPI flash crud.
> > The SPI bus controller (which is what this is for) and SPI-NOR
> > controller are two different things and must have two different slave
> > structures.
> 
> You mean mode_bits need to move in one more structure.
> Just leave about new SPI-NOR as of now for this release we discuss more
> soon.

The mode_bits have no place in this structure. The slave can indicate whether it 
can be connected over 1,2,4... lines , but must not indicate that it supports 
some SPI-flash specific properties.

Best regards,
Marek Vasut