Certain platforms contain peripherals which have contiguous memory alignment requirements, necessitating the use of the alignment argument when obtaining CMA memory. The current default maximum CMA_ALIGNMENT of order 9 translates into a 1MB alignment on systems with a 4K page size. To accommodate systems with peripherals with even larger alignment requirements, increase the upper-bound of CMA_ALIGNMENT from order 9 to order 12.
Marc Carino (1): cma: increase CMA_ALIGNMENT upper limit to 12
drivers/base/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
Some systems require a larger maximum PAGE_SIZE order for CMA allocations. To accommodate such systems, increase the upper-bound of the CMA_ALIGNMENT range to 12 (which ends up being 16MB on systems with 4K pages).
Signed-off-by: Marc Carino marc.ceeeee@gmail.com --- drivers/base/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig index 8fa8dea..0fb820c 100644 --- a/drivers/base/Kconfig +++ b/drivers/base/Kconfig @@ -253,7 +253,7 @@ endchoice
config CMA_ALIGNMENT int "Maximum PAGE_SIZE order of alignment for contiguous buffers" - range 4 9 + range 4 12 default 8 help DMA mapping framework by default aligns all buffers to the smallest
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