[PATCH 00/18] spi/xilinx: Speed-up

Ricardo Ribalda Delgado ricardo.ribalda at gmail.com
Fri Jan 23 08:08:32 PST 2015


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 at 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 at 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 (irq):
root at 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

This set of patches supersedes the previous patchet with only LSB_FIRST and LOOP

Ricardo Ribalda Delgado (18):
  spi/xilinx: Support for spi mode LSB_FIRST
  spi/xilinx: Support for spi mode LOOP
  spi/xilinx: Simplify data read from the Rx FIFO
  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: Reset core before buffer_size detection
  spi/xilinx: Remove remaining_words driver data variable
  spi/xilinx: Check number of slaves range

 drivers/spi/spi-xilinx.c | 306 ++++++++++++++++++++++-------------------------
 1 file changed, 146 insertions(+), 160 deletions(-)

-- 
2.1.4




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