Merge tag 'dma-mapping-4.18' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping updates from Christoph Hellwig:

 - replace the force_dma flag with a dma_configure bus method. (Nipun
   Gupta, although one patch is іncorrectly attributed to me due to a
   git rebase bug)

 - use GFP_DMA32 more agressively in dma-direct. (Takashi Iwai)

 - remove PCI_DMA_BUS_IS_PHYS and rely on the dma-mapping API to do the
   right thing for bounce buffering.

 - move dma-debug initialization to common code, and apply a few
   cleanups to the dma-debug code.

 - cleanup the Kconfig mess around swiotlb selection

 - swiotlb comment fixup (Yisheng Xie)

 - a trivial swiotlb fix. (Dan Carpenter)

 - support swiotlb on RISC-V. (based on a patch from Palmer Dabbelt)

 - add a new generic dma-noncoherent dma_map_ops implementation and use
   it for arc, c6x and nds32.

 - improve scatterlist validity checking in dma-debug. (Robin Murphy)

 - add a struct device quirk to limit the dma-mask to 32-bit due to
   bridge/system issues, and switch x86 to use it instead of a local
   hack for VIA bridges.

 - handle devices without a dma_mask more gracefully in the dma-direct
   code.

* tag 'dma-mapping-4.18' of git://git.infradead.org/users/hch/dma-mapping: (48 commits)
  dma-direct: don't crash on device without dma_mask
  nds32: use generic dma_noncoherent_ops
  nds32: implement the unmap_sg DMA operation
  nds32: consolidate DMA cache maintainance routines
  x86/pci-dma: switch the VIA 32-bit DMA quirk to use the struct device flag
  x86/pci-dma: remove the explicit nodac and allowdac option
  x86/pci-dma: remove the experimental forcesac boot option
  Documentation/x86: remove a stray reference to pci-nommu.c
  core, dma-direct: add a flag 32-bit dma limits
  dma-mapping: remove unused gfp_t parameter to arch_dma_alloc_attrs
  dma-debug: check scatterlist segments
  c6x: use generic dma_noncoherent_ops
  arc: use generic dma_noncoherent_ops
  arc: fix arc_dma_{map,unmap}_page
  arc: fix arc_dma_sync_sg_for_{cpu,device}
  arc: simplify arc_dma_sync_single_for_{cpu,device}
  dma-mapping: provide a generic dma-noncoherent implementation
  dma-mapping: simplify Kconfig dependencies
  riscv: add swiotlb support
  riscv: only enable ZONE_DMA32 for 64-bit
  ...

4 files changed, 27 insertions, 37 deletions

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index cd4fd85fde84..274bc064c41f 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -3,8 +3,16 @@
 # see Documentation/kbuild/kconfig-language.txt.
 #
 
+config 64BIT
+	bool
+
+config 32BIT
+	bool
+
 config RISCV
 	def_bool y
+	# even on 32-bit, physical (and DMA) addresses are > 32-bits
+	select PHYS_ADDR_T_64BIT
 	select OF
 	select OF_EARLY_FLATTREE
 	select OF_IRQ
@@ -22,7 +30,6 @@ config RISCV
 	select GENERIC_ATOMIC64 if !64BIT || !RISCV_ISA_A
 	select HAVE_MEMBLOCK
 	select HAVE_MEMBLOCK_NODE_MAP
-	select HAVE_DMA_API_DEBUG
 	select HAVE_DMA_CONTIGUOUS
 	select HAVE_GENERIC_DMA_COHERENT
 	select IRQ_DOMAIN
@@ -39,16 +46,9 @@ config RISCV
 config MMU
 	def_bool y
 
-# even on 32-bit, physical (and DMA) addresses are > 32-bits
-config ARCH_PHYS_ADDR_T_64BIT
-	def_bool y
-
 config ZONE_DMA32
 	bool
-	default y
-
-config ARCH_DMA_ADDR_T_64BIT
-	def_bool y
+	default y if 64BIT
 
 config PAGE_OFFSET
 	hex
@@ -101,7 +101,6 @@ choice
 
 config ARCH_RV32I
 	bool "RV32I"
-	select CPU_SUPPORTS_32BIT_KERNEL
 	select 32BIT
 	select GENERIC_ASHLDI3
 	select GENERIC_ASHRDI3
@@ -109,13 +108,13 @@ config ARCH_RV32I
 
 config ARCH_RV64I
 	bool "RV64I"
-	select CPU_SUPPORTS_64BIT_KERNEL
 	select 64BIT
 	select HAVE_FUNCTION_TRACER
 	select HAVE_FUNCTION_GRAPH_TRACER
 	select HAVE_FTRACE_MCOUNT_RECORD
 	select HAVE_DYNAMIC_FTRACE
 	select HAVE_DYNAMIC_FTRACE_WITH_REGS
+	select SWIOTLB
 
 endchoice
 
@@ -171,11 +170,6 @@ config NR_CPUS
 	depends on SMP
 	default "8"
 
-config CPU_SUPPORTS_32BIT_KERNEL
-	bool
-config CPU_SUPPORTS_64BIT_KERNEL
-	bool
-
 choice
 	prompt "CPU Tuning"
 	default TUNE_GENERIC
@@ -202,24 +196,6 @@ endmenu
 
 menu "Kernel type"
 
-choice
-	prompt "Kernel code model"
-	default 64BIT
-
-config 32BIT
-	bool "32-bit kernel"
-	depends on CPU_SUPPORTS_32BIT_KERNEL
-	help
-	  Select this option to build a 32-bit kernel.
-
-config 64BIT
-	bool "64-bit kernel"
-	depends on CPU_SUPPORTS_64BIT_KERNEL
-	help
-	  Select this option to build a 64-bit kernel.
-
-endchoice
-
 source "mm/Kconfig"
 
 source "kernel/Kconfig.preempt"
diff --git a/arch/riscv/include/asm/dma-mapping.h b/arch/riscv/include/asm/dma-mapping.h
new file mode 100644
index 000000000000..8facc1c8fa05
--- /dev/null
+++ b/arch/riscv/include/asm/dma-mapping.h
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0
+#ifndef _RISCV_ASM_DMA_MAPPING_H
+#define _RISCV_ASM_DMA_MAPPING_H 1
+
+#ifdef CONFIG_SWIOTLB
+#include <linux/swiotlb.h>
+static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
+{
+	return &swiotlb_dma_ops;
+}
+#else
+#include <asm-generic/dma-mapping.h>
+#endif /* CONFIG_SWIOTLB */
+
+#endif /* _RISCV_ASM_DMA_MAPPING_H */
diff --git a/arch/riscv/include/asm/pci.h b/arch/riscv/include/asm/pci.h
index 0f2fc9ef20fc..b3638c505728 100644
--- a/arch/riscv/include/asm/pci.h
+++ b/arch/riscv/include/asm/pci.h
@@ -26,9 +26,6 @@
 /* RISC-V shim does not initialize PCI bus */
 #define pcibios_assign_all_busses() 1
 
-/* We do not have an IOMMU */
-#define PCI_DMA_BUS_IS_PHYS 1
-
 extern int isa_dma_bridge_buggy;
 
 #ifdef CONFIG_PCI
diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
index c11f40c1b2a8..ee44a48faf79 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -29,6 +29,7 @@
 #include <linux/of_fdt.h>
 #include <linux/of_platform.h>
 #include <linux/sched/task.h>
+#include <linux/swiotlb.h>
 
 #include <asm/setup.h>
 #include <asm/sections.h>
@@ -206,6 +207,7 @@ void __init setup_arch(char **cmdline_p)
 	setup_bootmem();
 	paging_init();
 	unflatten_device_tree();
+	swiotlb_init(1);
 
 #ifdef CONFIG_SMP
 	setup_smp();