[RFC PATCH 4/5] arm64: Provide arch_sync_dma_ batched helpers

[Barry Song]

From: Barry Song <v-songbaohua at oppo.com>

arch_sync_dma_for_device_batch_add() and arch_sync_dma_for_cpu_batch_add()
batch the DMA sync operations, and arch_sync_dma_batch_flush() waits for
their completion all together.

Cc: Catalin Marinas <catalin.marinas at arm.com>
Cc: Will Deacon <will at kernel.org>
Cc: Marek Szyprowski <m.szyprowski at samsung.com>
Cc: Robin Murphy <robin.murphy at arm.com>
Cc: Ada Couprie Diaz <ada.coupriediaz at arm.com>
Cc: Ard Biesheuvel <ardb at kernel.org>
Cc: Marc Zyngier <maz at kernel.org>
Cc: Anshuman Khandual <anshuman.khandual at arm.com>
Cc: Ryan Roberts <ryan.roberts at arm.com>
Cc: Suren Baghdasaryan <surenb at google.com>
Cc: Tangquan Zheng <zhengtangquan at oppo.com>
Cc: linux-arm-kernel at lists.infradead.org
Cc: linux-kernel at vger.kernel.org
Cc: iommu at lists.linux.dev
Signed-off-by: Barry Song <v-songbaohua at oppo.com>
---
 arch/arm64/Kconfig          |  1 +
 arch/arm64/mm/dma-mapping.c | 24 ++++++++++++++++++++++++
 include/linux/dma-map-ops.h |  8 ++++++++
 kernel/dma/Kconfig          |  3 +++
 4 files changed, 36 insertions(+)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 6663ffd23f25..1ecf8a1c2458 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -112,6 +112,7 @@ config ARM64
 	select ARCH_SUPPORTS_SCHED_CLUSTER
 	select ARCH_SUPPORTS_SCHED_MC
 	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
+	select ARCH_WANT_BATCHED_DMA_SYNC
 	select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
 	select ARCH_WANT_DEFAULT_BPF_JIT
 	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
index b2b5792b2caa..9ac1ddd1bb9c 100644
--- a/arch/arm64/mm/dma-mapping.c
+++ b/arch/arm64/mm/dma-mapping.c
@@ -31,6 +31,30 @@ void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
 	dcache_inval_poc(start, start + size);
 }
 
+void arch_sync_dma_for_device_batch_add(phys_addr_t paddr, size_t size,
+			      enum dma_data_direction dir)
+{
+	unsigned long start = (unsigned long)phys_to_virt(paddr);
+
+	dcache_clean_poc_nosync(start, start + size);
+}
+
+void arch_sync_dma_for_cpu_batch_add(phys_addr_t paddr, size_t size,
+			   enum dma_data_direction dir)
+{
+	unsigned long start = (unsigned long)phys_to_virt(paddr);
+
+	if (dir == DMA_TO_DEVICE)
+		return;
+
+	dcache_inval_poc_nosync(start, start + size);
+}
+
+void arch_sync_dma_batch_flush(void)
+{
+	dsb(sy);
+}
+
 void arch_dma_prep_coherent(struct page *page, size_t size)
 {
 	unsigned long start = (unsigned long)page_address(page);
diff --git a/include/linux/dma-map-ops.h b/include/linux/dma-map-ops.h
index 10882d00cb17..8fcd0a9c1f39 100644
--- a/include/linux/dma-map-ops.h
+++ b/include/linux/dma-map-ops.h
@@ -367,6 +367,14 @@ static inline void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
 }
 #endif /* ARCH_HAS_SYNC_DMA_FOR_CPU */
 
+#ifdef CONFIG_ARCH_WANT_BATCHED_DMA_SYNC
+void arch_sync_dma_for_device_batch_add(phys_addr_t paddr, size_t size,
+		enum dma_data_direction dir);
+void arch_sync_dma_for_cpu_batch_add(phys_addr_t paddr, size_t size,
+		enum dma_data_direction dir);
+void arch_sync_dma_batch_flush(void);
+#endif
+
 #ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL
 void arch_sync_dma_for_cpu_all(void);
 #else
diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig
index 31cfdb6b4bc3..2785099b2fa0 100644
--- a/kernel/dma/Kconfig
+++ b/kernel/dma/Kconfig
@@ -78,6 +78,9 @@ config ARCH_HAS_DMA_PREP_COHERENT
 config ARCH_HAS_FORCE_DMA_UNENCRYPTED
 	bool
 
+config ARCH_WANT_BATCHED_DMA_SYNC
+	bool
+
 #
 # Select this option if the architecture assumes DMA devices are coherent
 # by default.
-- 
2.39.3 (Apple Git-146)