spi: spi-ti-qspi: switch to polling mode for better r/w performance

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Currently word completion interrupt is fired for transfer of every
word(8bit to 128bit in size). This adds a lot of overhead, and decreases
r/w throughput. It hardly takes 3us(@48MHz) for 128bit r/w to complete,
hence its better to poll on word complete bit to be set in
QSPI_SPI_STATUS_REG instead of using interrupts.
This increases the throughput by 30% in both read and write case.

So, switch to polling mode instead of interrupts to determine completion
of word transfer.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

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Vignesh R 2015-10-13 15:51:05 +05:30 • committed by Mark Brown

parent 6ff33f3902

commit 57c2ecd9bf

1 changed files with 20 additions and 54 deletions

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drivers/spi/spi-ti-qspi.c

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