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In nxp_fspi_select_mem() the RX sample clock source (MCR0[RXCLKSRC]) and the DLL control registers (DLLxCR) are reconfigured while the FlexSPI module is still enabled. According to the FlexSPI reference manual initialization sequence, MCR0 and the DLL control registers should be programmed while the module is in stop mode, i.e. with MCR0[MDIS] set to 1, and the module re-enabled (MCR0[MDIS] = 0) afterwards. Wrap the RX sample clock source selection and the DLL calibration/ override reconfiguration in a stop-mode window to align with the RM and avoid reconfiguring timing-critical registers while the module is active. Signed-off-by: Haibo Chen <haibo.chen@nxp.com> Reviewed-by: Frank Li <Frank.Li@nxp.com> Link: https://patch.msgid.link/20260728-fspi-clock-v2-2-dbe786a4a6eb@nxp.com Signed-off-by: Mark Brown <broonie@kernel.org>
Linux kernel ============ The Linux kernel is the core of any Linux operating system. It manages hardware, system resources, and provides the fundamental services for all other software. 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