[PATCH v2 5/5] of: address: Always use dma_default_coherent for default coherency

[Jiaxun Yang]

As for now all arches have dma_default_coherent matched with default
DMA coherency for of devices, so there is no need to have a standalone
config option.

Note for PowerPC: CONFIG_OF_DMA_DEFUALT_COHERENT was only selected when
CONFIG_NOT_COHERENT_CACHE is false, in this case dma_default_coherent will
be true, so it still matches present behavior.

Note for RISCV: dma_default_coherent is set to true in this series.

Signed-off-by: Jiaxun Yang <jiaxun.y...@flygoat.com>
---
 arch/powerpc/Kconfig |  1 -
 arch/riscv/Kconfig   |  1 -
 drivers/of/Kconfig   |  4 ----
 drivers/of/address.c | 10 +---------
 4 files changed, 1 insertion(+), 15 deletions(-)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 2c9cdf1d8761..c67e5da714f7 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -272,7 +272,6 @@ config PPC
        select NEED_PER_CPU_PAGE_FIRST_CHUNK    if PPC64
        select NEED_SG_DMA_LENGTH
        select OF
-       select OF_DMA_DEFAULT_COHERENT          if !NOT_COHERENT_CACHE
        select OF_EARLY_FLATTREE
        select OLD_SIGACTION                    if PPC32
        select OLD_SIGSUSPEND
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index b71ce992c0c0..a79663191228 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -119,7 +119,6 @@ config RISCV
        select MODULES_USE_ELF_RELA if MODULES
        select MODULE_SECTIONS if MODULES
        select OF
-       select OF_DMA_DEFAULT_COHERENT
        select OF_EARLY_FLATTREE
        select OF_IRQ
        select PCI_DOMAINS_GENERIC if PCI
diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
index 644386833a7b..e40f10bf2ba4 100644
--- a/drivers/of/Kconfig
+++ b/drivers/of/Kconfig
@@ -102,8 +102,4 @@ config OF_OVERLAY
 config OF_NUMA
        bool
 
-config OF_DMA_DEFAULT_COHERENT
-       # arches should select this if DMA is coherent by default for OF devices
-       bool
-
 endif # OF
diff --git a/drivers/of/address.c b/drivers/of/address.c
index c105d66a1fa4..23ade4919853 100644
--- a/drivers/of/address.c
+++ b/drivers/of/address.c
@@ -1103,15 +1103,7 @@ phys_addr_t __init of_dma_get_max_cpu_address(struct 
device_node *np)
 bool of_dma_is_coherent(struct device_node *np)
 {
        struct device_node *node;
-       bool is_coherent = IS_ENABLED(CONFIG_OF_DMA_DEFAULT_COHERENT);
-
-       /*
-        * DT-based MIPS doesn't use OF_DMA_DEFAULT_COHERENT, but
-        * might override the system-wide default at runtime.
-        */
-#if defined(CONFIG_MIPS) && defined(CONFIG_DMA_NONCOHERENT)
-       is_coherent = dma_default_coherent;
-#endif
+       bool is_coherent = dma_default_coherent;
 
        node = of_node_get(np);
 
-- 
2.37.1 (Apple Git-137.1)