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From:   Christoph Hellwig <hch@lst.de>
To:     Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org,
        iommu@lists.linux-foundation.org
Subject: [PATCH 4/6] driver core: lift dma_default_coherent into common code
Date:   Wed, 10 Feb 2021 10:56:39 +0100
Message-Id: <20210210095641.23856-5-hch@lst.de>
In-Reply-To: <20210210095641.23856-1-hch@lst.de>
References: <20210210095641.23856-1-hch@lst.de>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
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Lift the dma_default_coherent variable from the mips architecture code
to the driver core.  This allows an architecture to sdefault all device
to be DMA coherent at run time, even if the kernel is build with support
for DMA noncoherent device.  By allowing device_initialize to set the
->dma_coherent field to this default the amount of arch hooks required
for this behavior can be greatly reduced.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/mips/Kconfig                     |  1 -
 arch/mips/alchemy/common/setup.c      |  2 +-
 arch/mips/include/asm/dma-coherence.h | 22 ----------------------
 arch/mips/kernel/setup.c              |  4 ----
 arch/mips/mm/c-r4k.c                  |  2 +-
 arch/mips/mm/dma-noncoherent.c        |  1 -
 arch/mips/mti-malta/malta-setup.c     |  2 +-
 arch/mips/pci/pci-alchemy.c           |  2 +-
 arch/mips/pistachio/init.c            |  1 -
 drivers/base/core.c                   |  6 ++++++
 include/linux/dma-map-ops.h           |  5 ++---
 kernel/dma/Kconfig                    |  3 ---
 kernel/dma/mapping.c                  |  2 ++
 13 files changed, 14 insertions(+), 39 deletions(-)
 delete mode 100644 arch/mips/include/asm/dma-coherence.h

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 0a17bedf4f0dba..0e86162df65541 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -1128,7 +1128,6 @@ config ARCH_SUPPORTS_UPROBES
 	bool
 
 config DMA_MAYBE_COHERENT
-	select ARCH_HAS_DMA_COHERENCE_H
 	select DMA_NONCOHERENT
 	bool
 
diff --git a/arch/mips/alchemy/common/setup.c b/arch/mips/alchemy/common/setup.c
index 39e5b9cd882b10..2388d68786f4a7 100644
--- a/arch/mips/alchemy/common/setup.c
+++ b/arch/mips/alchemy/common/setup.c
@@ -28,8 +28,8 @@
 #include <linux/init.h>
 #include <linux/ioport.h>
 #include <linux/mm.h>
+#include <linux/dma-map-ops.h> /* for dma_default_coherent */
 
-#include <asm/dma-coherence.h>
 #include <asm/mipsregs.h>
 
 #include <au1000.h>
diff --git a/arch/mips/include/asm/dma-coherence.h b/arch/mips/include/asm/dma-coherence.h
deleted file mode 100644
index 846c5ade30d12d..00000000000000
--- a/arch/mips/include/asm/dma-coherence.h
+++ /dev/null
@@ -1,22 +0,0 @@
-/*
- * This file is subject to the terms and conditions of the GNU General Public
- * License.  See the file "COPYING" in the main directory of this archive
- * for more details.
- *
- * Copyright (C) 2006  Ralf Baechle <ralf@linux-mips.org>
- *
- */
-#ifndef __ASM_DMA_COHERENCE_H
-#define __ASM_DMA_COHERENCE_H
-
-#ifdef CONFIG_DMA_MAYBE_COHERENT
-extern bool dma_default_coherent;
-static inline bool dev_is_dma_coherent(struct device *dev)
-{
-	return dma_default_coherent;
-}
-#else
-#define dma_default_coherent	(!IS_ENABLED(CONFIG_DMA_NONCOHERENT))
-#endif
-
-#endif
diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
index aef418e6e65879..d6b2ba527f5b81 100644
--- a/arch/mips/kernel/setup.c
+++ b/arch/mips/kernel/setup.c
@@ -37,7 +37,6 @@
 #include <asm/cdmm.h>
 #include <asm/cpu.h>
 #include <asm/debug.h>
-#include <asm/dma-coherence.h>
 #include <asm/sections.h>
 #include <asm/setup.h>
 #include <asm/smp-ops.h>
@@ -807,9 +806,6 @@ arch_initcall(debugfs_mips);
 #endif
 
 #ifdef CONFIG_DMA_MAYBE_COHERENT
-bool dma_default_coherent;
-EXPORT_SYMBOL_GPL(dma_default_coherent);
-
 static int __init setcoherentio(char *str)
 {
 	dma_default_coherent = true;
diff --git a/arch/mips/mm/c-r4k.c b/arch/mips/mm/c-r4k.c
index 58afbc3e4ada03..3c4a50e12cebd4 100644
--- a/arch/mips/mm/c-r4k.c
+++ b/arch/mips/mm/c-r4k.c
@@ -19,6 +19,7 @@
 #include <linux/mm.h>
 #include <linux/export.h>
 #include <linux/bitops.h>
+#include <linux/dma-map-ops.h> /* for dma_default_coherent */
 
 #include <asm/bcache.h>
 #include <asm/bootinfo.h>
@@ -35,7 +36,6 @@
 #include <asm/war.h>
 #include <asm/cacheflush.h> /* for run_uncached() */
 #include <asm/traps.h>
-#include <asm/dma-coherence.h>
 #include <asm/mips-cps.h>
 
 /*
diff --git a/arch/mips/mm/dma-noncoherent.c b/arch/mips/mm/dma-noncoherent.c
index 38d3d9143b47fb..90b562753eb892 100644
--- a/arch/mips/mm/dma-noncoherent.c
+++ b/arch/mips/mm/dma-noncoherent.c
@@ -10,7 +10,6 @@
 
 #include <asm/cache.h>
 #include <asm/cpu-type.h>
-#include <asm/dma-coherence.h>
 #include <asm/io.h>
 
 /*
diff --git a/arch/mips/mti-malta/malta-setup.c b/arch/mips/mti-malta/malta-setup.c
index 1cdcb76d393ed1..21cb3ac1237b76 100644
--- a/arch/mips/mti-malta/malta-setup.c
+++ b/arch/mips/mti-malta/malta-setup.c
@@ -13,8 +13,8 @@
 #include <linux/pci.h>
 #include <linux/screen_info.h>
 #include <linux/time.h>
+#include <linux/dma-map-ops.h> /* for dma_default_coherent */
 
-#include <asm/dma-coherence.h>
 #include <asm/fw/fw.h>
 #include <asm/mips-cps.h>
 #include <asm/mips-boards/generic.h>
diff --git a/arch/mips/pci/pci-alchemy.c b/arch/mips/pci/pci-alchemy.c
index 54c86b40d30498..1c722dd0c1302d 100644
--- a/arch/mips/pci/pci-alchemy.c
+++ b/arch/mips/pci/pci-alchemy.c
@@ -17,8 +17,8 @@
 #include <linux/init.h>
 #include <linux/syscore_ops.h>
 #include <linux/vmalloc.h>
+#include <linux/dma-map-ops.h> /* for dma_default_coherent */
 
-#include <asm/dma-coherence.h>
 #include <asm/mach-au1x00/au1000.h>
 #include <asm/tlbmisc.h>
 
diff --git a/arch/mips/pistachio/init.c b/arch/mips/pistachio/init.c
index 558995ed6fe886..7d3057e586d277 100644
--- a/arch/mips/pistachio/init.c
+++ b/arch/mips/pistachio/init.c
@@ -13,7 +13,6 @@
 #include <linux/of_fdt.h>
 
 #include <asm/cacheflush.h>
-#include <asm/dma-coherence.h>
 #include <asm/fw/fw.h>
 #include <asm/mips-boards/generic.h>
 #include <asm/mips-cps.h>
diff --git a/drivers/base/core.c b/drivers/base/core.c
index 6eb4c7a904c560..7c0406e675e98f 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -28,6 +28,7 @@
 #include <linux/sched/signal.h>
 #include <linux/sched/mm.h>
 #include <linux/sysfs.h>
+#include <linux/dma-map-ops.h> /* for dma_default_coherent */
 
 #include "base.h"
 #include "power/power.h"
@@ -2603,6 +2604,11 @@ void device_initialize(struct device *dev)
 	INIT_LIST_HEAD(&dev->links.suppliers);
 	INIT_LIST_HEAD(&dev->links.defer_sync);
 	dev->links.status = DL_DEV_NO_DRIVER;
+#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)
+	dev->dma_coherent = dma_default_coherent;
+#endif
 }
 EXPORT_SYMBOL_GPL(device_initialize);
 
diff --git a/include/linux/dma-map-ops.h b/include/linux/dma-map-ops.h
index 70fcd0f610ea48..1e98b8c1e055a9 100644
--- a/include/linux/dma-map-ops.h
+++ b/include/linux/dma-map-ops.h
@@ -229,11 +229,10 @@ bool dma_free_from_pool(struct device *dev, void *start, size_t size);
 int dma_direct_set_offset(struct device *dev, phys_addr_t cpu_start,
 		dma_addr_t dma_start, u64 size);
 
-#ifdef CONFIG_ARCH_HAS_DMA_COHERENCE_H
-#include <asm/dma-coherence.h>
-#elif defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
+#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)
+extern bool dma_default_coherent;
 static inline bool dev_is_dma_coherent(struct device *dev)
 {
 	return dev->dma_coherent;
diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig
index 479fc145acfc16..77b4055087430c 100644
--- a/kernel/dma/Kconfig
+++ b/kernel/dma/Kconfig
@@ -33,9 +33,6 @@ config NEED_DMA_MAP_STATE
 config ARCH_DMA_ADDR_T_64BIT
 	def_bool 64BIT || PHYS_ADDR_T_64BIT
 
-config ARCH_HAS_DMA_COHERENCE_H
-	bool
-
 config ARCH_HAS_DMA_SET_MASK
 	bool
 
diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index f87a89d086544b..84de6b1c5fab49 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -16,6 +16,8 @@
 #include "debug.h"
 #include "direct.h"
 
+bool dma_default_coherent;
+
 /*
  * Managed DMA API
  */
-- 
2.29.2