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https://github.com/brain-hackers/u-boot-brain
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60acde43d7
The RDY bit indicates that a transfer is complete. This needs to be cleared by SW before every single HW transaction, rather than only at the start of each SW transaction (those being made up of n HW transactions). It seems that earlier HW may have cleared this bit autonomously when starting a new transfer, and hence this code was not needed in practice. However, this is generally a good idea in all cases. In Tegra124, the HW behaviour appears to have changed, and SW must explicitly clear this bit. Otherwise, SW will believe that transfers have completed when they have not, and may e.g. read stale data from the RX FIFO. Signed-off-by: Yen Lin <yelin@nvidia.com> [swarren, rewrote commit description, unified duplicate RDY clearing code and moved it right before the start of the HW transaction, unconditionally exit loop after reading RX data, rather than checking if TX FIFO is empty, since it is guaranteed to be] Signed-off-by: Stephen Warren <swarren@nvidia.com> Reviewed-by: Jagannadha Sutradharudu Teki <jaganna@xilinx.com> |
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| .. | ||
| bios_emulator | ||
| block | ||
| bootcount | ||
| crypto | ||
| ddr/fsl | ||
| dfu | ||
| dma | ||
| fpga | ||
| gpio | ||
| hwmon | ||
| i2c | ||
| input | ||
| misc | ||
| mmc | ||
| mtd | ||
| net | ||
| pci | ||
| pcmcia | ||
| power | ||
| qe | ||
| rtc | ||
| serial | ||
| sound | ||
| spi | ||
| tpm | ||
| twserial | ||
| usb | ||
| video | ||
| watchdog | ||
| Makefile | ||