With STM32 QSPI, it is possible to poll the status register of the device. This could be done to offload the CPU during an operation (erase or program a SPI NAND for example). spi_mem_poll_status API has been added to handle this feature. This new function take care of the offload/non-offload cases. For the non-offload case, use read_poll_timeout() to poll the status in order to release CPU during this phase. For example, previously, when erasing large area, in non-offload case, CPU load can reach ~50%, now it decrease to ~35%. Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com> Signed-off-by: Christophe Kerello <christophe.kerello@foss.st.com> Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com> Link: https://lore.kernel.org/r/20210518162754.15940-2-patrice.chotard@foss.st.com Signed-off-by: Mark Brown <broonie@kernel.org>
13 KiB
13 KiB