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49bd706aac
QSPI may failed to map enough memory (256MB) for AHB read in previous implementation, especially in 3G/1G memory layout kernel. Dynamically map memory to avoid such issue. This implementation generally map QUADSPI_MAX_IOMAP (default 4MB) memory for AHB read, it should be enough for common scenarios, and the side effect (0.6% performance drop) is minor. Previous implementation root@imx6qdlsolo:~# dd if=/dev/mtd0 of=/dev/null bs=1K count=32K 32768+0 records in 32768+0 records out 33554432 bytes (34 MB) copied, 2.16006 s, 15.5 MB/s root@imx6qdlsolo:~# dd if=/dev/mtd0 of=/dev/null bs=32M count=1 1+0 records in 1+0 records out 33554432 bytes (34 MB) copied, 1.43149 s, 23.4 MB/s After applied the patch root@imx6qdlsolo:~# dd if=/dev/mtd0 of=/dev/null bs=1K count=32K 32768+0 records in 32768+0 records out 33554432 bytes (34 MB) copied, 2.1743 s, 15.4 MB/s root@imx6qdlsolo:~# dd if=/dev/mtd0 of=/dev/null bs=32M count=1 1+0 records in 1+0 records out 33554432 bytes (34 MB) copied, 1.43158 s, 23.4 MB/s Signed-off-by: Han Xu <han.xu@freescale.com> Signed-off-by: Frank Li <Frank.Li@freescale.com> Signed-off-by: Brian Norris <computersforpeace@gmail.com>