path: root/arch/mips/powertv/Makefile
diff options
authorDavid VomLehn <dvomlehn@cisco.com>2010-05-21 11:25:36 -0700
committerRalf Baechle <ralf@linux-mips.org>2010-08-05 13:25:40 +0100
commitca36c36b7821b573fe06ce6bc34db03b557f3ce4 (patch)
tree28fe24b5080e29ca62ff4d1b4bbf5afc83084792 /arch/mips/powertv/Makefile
parent36f217d9df3e6bf8e6ae7647827b485b79dbaf8e (diff)
MIPS: PowerTV: Use O(1) algorthm for phys_to_dma/dma_to_phys
Replace phys_to_dma()/dma_to_phys() looping algorithm with an O(1) algorithm The approach taken is inspired by the sparse memory implementation: take a certain number of high-order bits off the address them, use this as an index into a table containing an offset to the desired address and add it to the original value. There is a table for mapping physical addresses to DMA addresses and another one for the reverse mapping. The table sizes depend on how fine-grained the mappings need to be; Coarser granularity less to smaller tables. On a processor with 32-bit physical and DMA addresses, with 4 MIB granularity, memory usage is two 2048-byte arrays. Each 32-byte cache line thus covers 64 MiB of address space. Also, renames phys_to_bus() to phys_to_dma() and bus_to_phys() to dma_to_phys() to align with kernel usage. [Ralf: Fixed silly build breakage due to stackoverflow warning caused by huge array on stack.] Signed-off-by: David VomLehn <dvomlehn@cisco.com> To: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/1257/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/powertv/Makefile')
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/mips/powertv/Makefile b/arch/mips/powertv/Makefile
index 0a0d73c0564..e9fe1c6efe1 100644
--- a/arch/mips/powertv/Makefile
+++ b/arch/mips/powertv/Makefile
@@ -23,6 +23,7 @@
# under Linux.
-obj-y += init.o memory.o reset.o time.o powertv_setup.o asic/ pci/
+obj-y += init.o ioremap.o memory.o powertv_setup.o reset.o time.o \
+ asic/ pci/
EXTRA_CFLAGS += -Wall -Werror