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| author | Lokesh Vutla <lokeshvutla@ti.com> | 2016-03-24 10:32:00 (GMT) |
|---|---|---|
| committer | Tom Rini <trini@konsulko.com> | 2016-03-27 13:13:03 (GMT) |
| commit | 37217f0e0ae92be4a9bba4291d669868d4a26544 (patch) | |
| tree | 9294de6ca596bc669c5634238672cdc47992b479 /arch/arm/Kconfig | |
| parent | 1cd29f0abd787eb881523452a77e12dab1cb32c5 (diff) | |
| download | u-boot-fsl-qoriq-37217f0e0ae92be4a9bba4291d669868d4a26544.tar.xz | |
ARM: asm: types: Introduce DMA_ADDR_T_64BIT
dma_addr_t holds any valid DMA address. If the DMA API only uses 32-bit
addresses, dma_addr_t need only be 32 bits wide. Bus addresses, e.g., PCI BARs,
may be wider than 32 bits, but drivers do memory-mapped I/O to ioremapped
kernel virtual addresses, so they don't care about the size of the actual
bus addresses.
Also 32 bit ARM systems with LPAE enabled can use 64bit address space, but
DMA still use 32bit address like in case of DRA7 and Keystone platforms.
This is inspired from the Linux kernel types implementation[1]
[1] https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/include/linux/types.h#n142
Acked-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Diffstat (limited to 'arch/arm/Kconfig')
| -rw-r--r-- | arch/arm/Kconfig | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index e668994..9851065 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -7,6 +7,10 @@ config SYS_ARCH config ARM64 bool +config DMA_ADDR_T_64BIT + bool + default y if ARM64 + config HAS_VBAR bool |