[PATCH v2 00/15] spi/xilinx: Speed-up

[Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>]

This set of patches has been developed after using the core to access a spi
nor flash. The initial performance was not as desired. The following changes
have been done.

-This series of patches add driver support for hardware implemented modes:
LSB_FIRS, LOOP and CS_HIGH.

-There is support for irq less operations.

-The buffer size of the core is detected at probe time, speeding up the
operations.

-Code has been simplify and cleaned

This are the results, before and after the patchet

Original
root@qt5022:~# dd if=/dev/mtd0 of=/dev/null
16384+0 records in
16384+0 records out
8388608 bytes (8.4 MB) copied, 117.985 s, 71.1 kB/s

 37:        107      82853  Xilinx INTC Level   1  b0010000.spi-flash

After patchset (irq):
root@qt5022:~# dd if=/dev/mtd0 of=/dev/null
16384+0 records in
16384+0 records out
8388608 bytes (8.4 MB) copied, 49.009 s, 171 kB/s

After patchset (polling):
root@qt5022:~# dd if=/dev/mtd0 of=/dev/null
16384+0 records in
16384+0 records out
8388608 bytes (8.4 MB) copied, 41.2526 s, 203 kB/s

IRQS: ZERO

Changelog v2:

-Add patch spi/xilinx: Use polling mode on small transfers
-Merge spi/xilinx: Reset core before buffer_size detection with spi/xilinx: 
Simplify spi_fill_tx_fifo
-Fix codestyle on Remove rx_fn and tx_fn pointer
-Remove already merged patches

Ricardo Ribalda Delgado (15):
  spi/xilinx: Simplify spi_fill_tx_fifo
  spi/xilinx: Leave the IRQ always enabled.
  spi/xilinx: Code cleanup
  spi/xilinx: Use cached value of register
  spi/xilinx: Support cores with no interrupt
  spi/xilinx: Do not inhibit transmission in polling mode
  spi/xilinx: Support for spi mode CS_HIGH
  spi/xilinx: Remove rx_fn and tx_fn pointer
  spi/xilinx: Make spi_tx and spi_rx simmetric
  spi/xilinx: Convert remainding_bytes in remaining words
  spi/xilinx: Convert bits_per_word in bytes_per_word
  spi/xilinx: Remove iowrite/ioread wrappers
  spi/xilinx: Remove remaining_words driver data variable
  spi/xilinx: Check number of slaves range
  spi/xilinx: Use polling mode on small transfers

 drivers/spi/spi-xilinx.c | 337 ++++++++++++++++++++++-------------------------
 1 file changed, 157 insertions(+), 180 deletions(-)

-- 
2.1.4