Hi all,
This series split out second half of my previous series
"[PATCH 0/4] MIPS DMA coherence fixes".
It intends to use dma_default_coherent to determine the default coherency of
devicetree probed devices instead of hardcoding it with Kconfig options.
For some MIPS systems, dma_default_coherent is determined with either
bootloader or hardware registers in platform initilization code, and devicetree
does not explicility specify the coherency of the device, so we need the ability
to change the default coherency of devicetree probed devices.
For other platforms that supports noncoherent, dma_default_coherent is a fixed
value set by arch code. It's defaulted to false for most archs except RISC-V
and powerpc in some cases.
Thanks
- Jiaxun
---
v2:
- Add PATCH 1 to help with backporting
- Use Kconfig option to set dma_default_coherent
v3:
- Style fixes
- Squash setting ARCH_DMA_DEFAULT_COHERENT into PATCH 4
- Setting ARCH_DMA_DEFAULT_COHERENT for PowerPC
v4:
- Drop first patch
Jiaxun Yang (3):
dma-mapping: Provide a fallback dma_default_coherent
dma-mapping: Provide CONFIG_ARCH_DMA_DEFAULT_COHERENT
of: address: Always use dma_default_coherent for default coherency
arch/powerpc/Kconfig | 2 +-
arch/riscv/Kconfig | 2 +-
drivers/of/Kconfig | 4 ----
drivers/of/address.c | 2 +-
include/linux/dma-map-ops.h | 2 ++
kernel/dma/Kconfig | 7 +++++++
kernel/dma/mapping.c | 6 +++++-
7 files changed, 17 insertions(+), 8 deletions(-)
--
2.39.2 (Apple Git-143)
Provide a kconfig option to allow arches to manipulate default
value of dma_default_coherent in Kconfig.
Signed-off-by: Jiaxun Yang <[email protected]>
---
v3: Add comments
---
kernel/dma/Kconfig | 7 +++++++
kernel/dma/mapping.c | 2 +-
2 files changed, 8 insertions(+), 1 deletion(-)
diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig
index 56866aaa2ae1..6677d0e64d27 100644
--- a/kernel/dma/Kconfig
+++ b/kernel/dma/Kconfig
@@ -76,6 +76,13 @@ config ARCH_HAS_DMA_PREP_COHERENT
config ARCH_HAS_FORCE_DMA_UNENCRYPTED
bool
+#
+# Select this option if the architecture assumes DMA devices are coherent
+# by default.
+#
+config ARCH_DMA_DEFAULT_COHERENT
+ bool
+
config SWIOTLB
bool
select NEED_DMA_MAP_STATE
diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index 80f9663ffe26..9a4db5cce600 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -20,7 +20,7 @@
#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \
defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
-bool dma_default_coherent;
+bool dma_default_coherent = IS_ENABLED(CONFIG_ARCH_DMA_DEFAULT_COHERENT);
#endif
/*
--
2.39.2 (Apple Git-143)
As for now all arches have dma_default_coherent reflecting default
DMA coherency for of devices, so there is no need to have a standalone
config option.
Signed-off-by: Jiaxun Yang <[email protected]>
Reviewed-by: Rob Herring <[email protected]>
Acked-by: Michael Ellerman <[email protected]> (powerpc)
---
v3: Squash setting ARCH_DMA_DEFAULT_COHERENT into this patch.
---
arch/powerpc/Kconfig | 2 +-
arch/riscv/Kconfig | 2 +-
drivers/of/Kconfig | 4 ----
drivers/of/address.c | 2 +-
4 files changed, 3 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 26725cdef2be..6777f6158bdd 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -113,6 +113,7 @@ config PPC
#
select ARCH_32BIT_OFF_T if PPC32
select ARCH_DISABLE_KASAN_INLINE if PPC_RADIX_MMU
+ select ARCH_DMA_DEFAULT_COHERENT if !NOT_COHERENT_CACHE
select ARCH_ENABLE_MEMORY_HOTPLUG
select ARCH_ENABLE_MEMORY_HOTREMOVE
select ARCH_HAS_COPY_MC if PPC64
@@ -273,7 +274,6 @@ 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 3fb099bfa232..5a28e36b1ef1 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -12,6 +12,7 @@ config 32BIT
config RISCV
def_bool y
+ select ARCH_DMA_DEFAULT_COHERENT
select ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION
select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2
select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE
@@ -122,7 +123,6 @@ 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 4c0b169ef9bf..23ade4919853 100644
--- a/drivers/of/address.c
+++ b/drivers/of/address.c
@@ -1103,7 +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);
+ bool is_coherent = dma_default_coherent;
node = of_node_get(np);
--
2.39.2 (Apple Git-143)
> 2023年4月1日 10:15，Jiaxun Yang <[email protected]> 写道：
>
> Hi all,
>
> This series split out second half of my previous series
> "[PATCH 0/4] MIPS DMA coherence fixes".
>
> It intends to use dma_default_coherent to determine the default coherency of
> devicetree probed devices instead of hardcoding it with Kconfig options.
>
> For some MIPS systems, dma_default_coherent is determined with either
> bootloader or hardware registers in platform initilization code, and devicetree
> does not explicility specify the coherency of the device, so we need the ability
> to change the default coherency of devicetree probed devices.
>
> For other platforms that supports noncoherent, dma_default_coherent is a fixed
> value set by arch code. It's defaulted to false for most archs except RISC-V
> and powerpc in some cases.
Ping.
Is there any issue remain in this series?
Thanks
Jiaxun
>
> Thanks
> - Jiaxun
> ---
> v2:
> - Add PATCH 1 to help with backporting
> - Use Kconfig option to set dma_default_coherent
>
> v3:
> - Style fixes
> - Squash setting ARCH_DMA_DEFAULT_COHERENT into PATCH 4
> - Setting ARCH_DMA_DEFAULT_COHERENT for PowerPC
>
> v4:
> - Drop first patch
>
> Jiaxun Yang (3):
> dma-mapping: Provide a fallback dma_default_coherent
> dma-mapping: Provide CONFIG_ARCH_DMA_DEFAULT_COHERENT
> of: address: Always use dma_default_coherent for default coherency
>
> arch/powerpc/Kconfig | 2 +-
> arch/riscv/Kconfig | 2 +-
> drivers/of/Kconfig | 4 ----
> drivers/of/address.c | 2 +-
> include/linux/dma-map-ops.h | 2 ++
> kernel/dma/Kconfig | 7 +++++++
> kernel/dma/mapping.c | 6 +++++-
> 7 files changed, 17 insertions(+), 8 deletions(-)
>
> --
> 2.39.2 (Apple Git-143)
>
Thanks,
applied to the dma-mapping tree for 6.4.