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a4b2e6063c
In case the tap delay required by Arasan SDHCI is set to 0, the current embeddedsw firmware unconditionally writes IOU_SLCR SD_ITAPDLY to 0x100 (SD0_ITAPDLYENA=1, SD0_ITAPDLYSEL=0). Previous behavior was to keep the IOU_SLCR SD_ITAPDLY set to 0x0. There is some sort of difference in the behavior between SD0_ITAPDLYENA=1/0 with the same SD0_ITAPDLYSEL=0, even though the behavior should be identical -- zero delay added to rxclk_in line. The former breaks HS200 training in low temperature conditions. Write IOU_SLCR SD_ITAPDLY register to 0 using PM_MMIO_WRITE which seem to allow unrestricted WRITE access (and PM_MMIO_READ which allows read access) to the entire address space. This way, it is possible to work around the defect in IOCTL_SET_SD_TAPDELAY design which does not permit clearing SDx_ITAPDLYENA bit. Note that the embeddedsw firmware does not permit clearing the SD_ITAPDLY SD0_ITAPDLYENA bit, this bit can only ever be set by the firmware and it is often impossible to update the possibly broken firmware. Signed-off-by: Marek Vasut <marex@denx.de> Link: https://lore.kernel.org/r/20221215152023.8387-1-marex@denx.de Signed-off-by: Michal Simek <michal.simek@amd.com> |
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| Kconfig | ||
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| zynqmp-debug.c | ||
| zynqmp-debug.h | ||
| zynqmp.c | ||