Messages in this thread Patch in this message |  | | From | Songjun Wu <> | Subject | [PATCH v2 10/18] MIPS: lantiq: Unselect SWAP_IO_SPACE when LANTIQ is selected | Date | Fri, 3 Aug 2018 11:02:29 +0800 |
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SWAP_IO_SPACE macro prevents serial driver /drivers/tty/serial/lantiq.c to use readl/writel to replace ltq_r32/w32 which are SoC or platform specific APIs.
readl/writel are used for this serial driver to support multiple platforms and multiple architectures. The legacy lantiq platform(Danube) enables SWAP_IO_SPACE for supporting PCI due to some hardware bugs.
It's a little-endian bus plus PCI TX/RX swap enable impacted both data and control path for MIPS based platforms. But it is better to let PCI device driver to do endian swap since SWAP_IO_SPACE is a global wide macro which potentially impacts other peripheral like USB. ltq_r32/ltq_w32 is not impacted in other device drivers based on MIPS when SWAP_IO_SPACE is not selected as they use non-byte swapping OS API (__raw_read/__raw_writel).
Signed-off-by: Songjun Wu <songjun.wu@linux.intel.com> ---
Changes in v2: None
arch/mips/Kconfig | 1 - 1 file changed, 1 deletion(-)
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 2d34f17f3e24..2e7e0b538e52 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -400,7 +400,6 @@ config LANTIQ select SYS_SUPPORTS_VPE_LOADER select SYS_HAS_EARLY_PRINTK select GPIOLIB - select SWAP_IO_SPACE select BOOT_RAW select CLKDEV_LOOKUP select USE_OF -- 2.11.0
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